An amplifier for VUV photomultiplier operating in cryogenic environment Arneodo, F.; Benabderrahmane, M.L.; Dahal, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Volume:
824
Journal Article
Peer reviewed
We present the characterisation of an amplifier potentially interesting for noble liquid detectors. The design has been conceived considering the requirements of low power consumption (less than ...30mW), low noise, amplification factor of 10 at 100MHz and use of commercial components. The amplifier has been integrated onto an electronic board with a voltage divider to operate an Hamamatsu R11410 photomultiplier tube (used in XENON1T, Aprile et al. (2014) 1 dark matter experiment).
To find the optimal exercise program to be recommended in reducing adiposity and promoting long-term physical activity adherence in a sample of overweight adolescents.
Forty-five overweight ...adolescents were randomly divided into three exercise groups, to perform two phases of physical activity as follows: in the first phase, the first group performed a 16-week moderate-intensity resistance training (RT), the second group performed a 16-week high-intensity RT, and the third group performed a 16-week aerobic training (AT); in the second phase, all groups performed a 6-week AT. Anthropometric body composition and fitness measures were considered as outcome measures.
After the second protocol, both RT groups showed a significant improvement in percentage of fat mass (
= 5.843;
= 0.004;
= 0.133) and free fat mass (
= 6.254;
= 0.003;
= 0.141), and in fitness tests (
< 0.01). The VO
max values of the RT groups were significantly higher than those of the AT group (
= 4.264;
= 0.021;
= 0.183). The rate of adherence to exercise was an average of 94% in both RT groups, whereas in the AT group, it was 83%. During the 12-week post-intervention follow-up, the number of participants who continued to perform physical activities was significantly higher in both the RT groups than in the AT group (
< 0.05).
The present study provides preliminary evidence that moderate-to-intense RT, followed by AT, can be an effective treatment for overweight adolescents, and the positive effects are maintained even after 12 weeks of follow-up.
We report on weakly interacting massive particles (WIMPs) search results in the XENON100 detector using a nonrelativistic effective field theory approach. The data from science run II (34 kg×224.6 ...live days) were reanalyzed, with an increased recoil energy interval compared to previous analyses, ranging from (6.6–240) keVnr. The data are found to be compatible with the background-only hypothesis. We present 90% confidence level exclusion limits on the coupling constants of WIMP-nucleon effective operators using a binned profile likelihood method. We also consider the case of inelastic WIMP scattering, where incident WIMPs may up-scatter to a higher mass state, and set exclusion limits on this model as well.
Abstract
The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the ...emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the
$$^{222}$$
222
Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a
$$^{222}$$
222
Rn activity concentration of
$$10\,\mathrm{\,}\upmu \mathrm{Bq}/\mathrm{kg}$$
10
μ
Bq
/
kg
in
$$3.2\,\mathrm{t}$$
3.2
t
of xenon. The knowledge of the distribution of the
$$^{222}$$
222
Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the
$$^{222}$$
222
Rn activity concentration in XENON1T. The final
$$^{222}$$
222
Rn activity concentration of
$$(4.5\pm 0.1)\,\mathrm{\,}\upmu \mathrm{Bq}/\mathrm{kg}$$
(
4.5
±
0.1
)
μ
Bq
/
kg
in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.
Due to its fascinating structures, the Gran Sasso National Laboratory (LNGS) offers huge opportunities for communication and outreach activities conceived for students and general public. A great ...effort is devoted to the organisation of the "OPEN DAY", in which the scientific staff of Gran Sasso introduces non expert people to the main relevant research topics of the laboratory through interactive demonstrations and particle detectors. In particular, a portable cosmic rays telescope has been realized: the detector is used by LNGS team in pubblic events as well as to promote the scientific activities of the Laboratory. In order to point out the importance of the scientific culture for young people, LNGS is involved in the organisation of several training courses for students and teachers focused on the improvement of the knowledge on modern physics topics. Since May 2008 is operating in Teramo the "Galileium", an interactive museum for physics and astrophysics.
Little is known about the relation between serum lipid parameters and serial change in plaque composition using in vivo coronary imaging. The aim of this study was to examine the association between ...serum lipids and change in coronary plaque lipid burden assessed by near-infrared spectroscopy (NIRS).
We performed serial NIRS-intravascular ultrasound studies in 49 patients who underwent coronary angiography for an acute coronary syndrome (ACS) or stable ischemic symptoms. Univariable and multivariable linear regression analyses were applied to evaluate the relationship between serum lipid parameters and change in lipid core burden index at the 4-mm maximal segment (max LCBI4mm).
Mean patient age was 61 ± 9 y, 29% were women, 35% had an ACS clinical presentation, 78% received statin therapy at baseline, and median low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), total cholesterol and triglyceride levels were 101, 43, 174 and 133 mg/dL, respectively. During a median follow-up period of 13 months, max LCBI4mm significantly decreased from 277 to 194 (p = 0.001). On univariable analysis, the percent change in HDL-C negatively associated with the change in max LCBI4mm (β = −3.19, p = 0.004). There were no significant associations between the other lipid parameters and change in max LCBI4mm. On multivariable analysis, percent change in HDL-C remained significantly associated with the change in max LCBI4mm (p = 0.002).
Change in HDL-C, but not other lipids parameters, associated with changes in coronary plaque lipid burden assessed by NIRS. These findings highlight the potential therapeutic importance of high-density lipoprotein on serial change in plaque composition.
•Change in HDL-C inversely correlates with change in coronary lipid burden.•No association with other lipid parameters.•This highlights the potential importance of raising HDL-C.
A compact muon tracking system for didactic and outreach activities Antolini, R.; Candela, A.; Conicella, V. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Volume:
824
Journal Article
Peer reviewed
We present a cosmic ray telescope based on the use of plastic scintillator bars coupled to ASD-RGB1S-M Advansid Silicon Photomultipliers (SiPM) through wavelength shifter fibers. The system is ...comprised of 200 electronic channels organized into 10 couples of orthogonal planes allowing the 3D reconstruction of crossing muons. Two monolithic PCB boards have been designed to bias, readout all the SiPMs enclosed in the system, to monitor the working parameters and to remotely connect the detector. To make easier the display of muon tracks to non-expert users, two LED matrices, triggered by particle interactions, have been implemented. To improve the usability of the muon telescope, a controller board unit permits to select different levels of trigger and allows data acquisition for refined analyses for the more proficient user. A first prototype, funded by INFN and deployed in collaboration with NYUAD, is operating at the Toledo Metro station of Naples, while two further detectors will be developed and installed in Abu Dhabi in the next few months.
•A compact system for real time displaying of muon tracks is presented.•The system is based on scintillating plates composed of doped polystyrene bars.•By using SiPMs and corresponding LEDs the muon paths can be visualized.•The purpose of this system is to introduce the public to sub-nuclear particles.
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