Search

The development of low-background anisotropic detectors can offer a unique way to study those Dark Matter (DM) candidate particles able to induce nuclear recoils through the directionality technique. Among the anisotropic scintillators, the ZnWO$_{4}$ has unique features and is an excellent candidate for the purposes. Both the light output and the scintillation pulse shape depend on the impinging direction of heavy particles with respect to the crystallographic axes and can supply two independent modes to study the directionality and discriminate $\gamma/\beta$ radiation. Measurements to study the anisotropic and scintillation performances of ZnWO$_4$ are reported.

The long-standing model-independent annual modulation effect measured by DAMA deep underground at Gran Sasso Laboratory with different experimental configurations is summarized and perspectives will be highlighted. DAMA/LIBRA-phase2 set-up, $\simeq$ 250 kg highly radio-pure NaI(Tl) confirms the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature at high C.L.; the full exposure is 2.86 ton $\times$ yr over 22 annual cycles. The experiment is currently collecting data in the DAMA/LIBRA-phase2 empowered configuration with an even lower software energy threshold. Other recent claims are shortly commented.

A fall is an event where a person unintentionally and traumatically finds themselves on the floor or a lower level. Falls are very common, especially in the older adult population. One in four people falls at least once a year after age 65. Because of falls, there can be injuries, whereby there can be an impairment of health status. Fractures, reduced mobility, disability, and the need for institutionalization are potential consequences after falls. In older adult patients, especially frail ones, these types of complications are more common. There are several risk factors for falls. Falls generally result from a combination of factors operating simultaneously. Sarcopenia, cognitive impairment, or poly-pharmacotherapy are just a few examples of risk factors that are common in the older people. Through careful clinical evaluation, it is possible to identify risk factors and conditions predisposing to falls. In some cases, it is possible to correct these factors. Several types of treatment are available to restore the health status before the fall and prevent subsequent falls. Using multi-component interventions, the risk of falls can be effectively reduced. Aware that this review will not be exhaustive of such a broad topic, the purpose of this narrative review is to summarize relevant and recent evidence in the current literature to encapsulate fall-related risk factors, risk identification, fall prevention, and management, including various rehabilitation techniques. This article conforms to the Scale for Assessment of Narrative Review Articles (SANRA) guidelines.

Crystal scintillators and in particular inorganic scintillators play an important role in the investigation of Dark Matter (DM) and other rare processes. The investigation of a DM signature, as the annual modulation, or the directionality technique requires the use of highly radiopure detectors able to explore the very low energy region maintaining a high stability of the running conditions. In this paper, the cases of NaI(Tl), ZnWO4 and SrI2(Eu) crystal scintillators are described in the framework of our activities at the Gran Sasso National Laboratory of the INFN. Their role, the obtained results in DM investigation, as well as their potential and perspectives for the future are reviewed.

Purpose: Many semi-automated and fully-automated approaches have been proposed in literature to improve the objectivity of the estimation of conjunctival hyperemia, based on image processing analysis of eyes’ photographs. The purpose is to improve its evaluation using faster fully-automated systems and independent by the human subjectivity. Methods: In this work, we introduce a fully-automated analysis of the redness grading scales able to completely automatize the clinical procedure, starting from the acquired image to the redness estimation. In particular, we introduce a neural network model for the conjunctival segmentation followed by an image processing pipeline for the vessels network segmentation. From these steps, we extract some features already known in literature and whose correlation with the conjunctival redness has already been proved. Lastly, we implemented a predictive model for the conjunctival hyperemia using these features. Results: In this work, we used a dataset of images acquired during clinical practice.We trained a neural network model for the conjunctival segmentation, obtaining an average accuracy of 0.94 and a corresponding IoU score of 0.88 on a test set of images. The set of features extracted on these ROIs is able to correctly predict the Efron scale values with a Spearman’s correlation coefficient of 0.701 on a set of not previously used samples. Conclusions: The robustness of our pipeline confirms its possible usage in a clinical practice as a viable decision support system for the ophthalmologists.

Optical coherence tomography angiography (OCTA) is a non-invasive diagnostic instrument that has become indispensable for the management of age-related macular degeneration (AMD). OCTA allows quickly visualizing retinal and choroidal microvasculature, and in the last years, its use has increased in clinical practice as well as for research into the pathophysiology of AMD. This review provides a discussion of new technology and application of OCTA in intermediate and late AMD.

Profiting of the favourable conditions offered by the Gran Sasso underground laboratory and of the several low-background DAMA set-ups, many and competitive results have been obtained for rare processes. Here the main results will be briefly resumed and some more details about the latest activities will be given. In particular, the searches on ββdecays of 106Cd and 116Cd and the perspectives of a complementary investigation on those Dark Matter (DM) candidates inducing just nuclear recoils, by exploiting the directionality approach with the anisotropic ZnWO4 scintillators, will be underlined.

The DAMA/LIBRA experiment (~ 250 kg sensitive mass composed by highly radio-pure NaI(Tl)) is in data taking in the underground Laboratory of Gran Sasso (LNGS). In its first phase (DAMA/LIBRA-phase1) this experiment and the former DAMA/NaI experiment (~ 100 kg of highly radio-pure NaI(Tl)) collected data for 14 independent annual cycles, exploiting the model-independent Dark Matter (DM) annual modulation signature (total exposure 1.33 ton x yr). A DM annual modulation effect has been observed at 9.3 σ C.L., supporting the presence of DM particles in the galactic halo. No systematic or side reaction able to mimic the observed DM annual modulation has been found or suggested by anyone. Recent analyses on possible diurnal effects, on the Earth shadowing effect and on possible interpretation in terms of Mirror DM will be mentioned. At present DAMA/LIBRA is running in its phase2 with increased sensitivity.

The ZnWO4 crystal scintillator has unique features that make it very promising to realize a pioneering experiment to pursue Dark Matter investigation with the directionality technique. In particular in this detector the light output and the scintillation pulse shape for heavy particles (p, α, nuclear recoils) depend on the direction of the impinging particle with respect to the crystal axes, while the response to γ/β radiation is isotropic. The anisotropy of the light output can be considered to point out the presence in the diurnal counting rate of a Dark Matter signal produced by candidate particle inducing just nuclear recoils. In addition this crystal detector has also other important characteristics for a Dark Matter experiment: high light output, high level of radiopurity. In this paper the present performances of the developed ZnWO4 crystal scintillator will be summarized together with the possible future improvements. Some reachable sensitivities – under given assumptions – in the investigation of DM candidate particles with the directionality technique will also be addressed.

Many experimental observations and theoretical arguments have pointed out that a large fraction of the Universe is composed by Dark Matter particles. Many possibilities are open on the nature and interaction types of such relic particles. In particular, this paper summarizes the main results obtained by exploiting the model independent Dark Matter annual modulation signature for the presence of Dark Matter particles in the galactic halo by DAMA experiment.

The DAMA/LIBRA experiment (~ 250 kg sensitive mass composed by highly radio-pure NaI(Tl)) is in data taking in the underground Laboratory of Gran Sasso (LNGS). Its first phase (DAMA/LIBRA–phase1) and the former DAMA/NaI experiment (~ 100 kg of highly radio-pure NaI(Tl)) collected data for 14 independent annual cycles, exploiting the model-independent Dark Matter (DM) annual modulation signature (total exposure 1:33 ton × yr). A DM annual modulation effect has been observed at 9.3 σ C.L., supporting the presence of DM particles in the galactic halo. No systematic or side reaction able to mimic the observed DM annual modulation has been found or suggested by anyone. Recent analyses on possible diurnal effects, on the Earth shadowing effect and on possible interpretation in terms of Asymmetric Mirror DM will be mentioned. At present DAMA/LIBRA is running in its phase2 with increased sensitivity.

The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA-phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA-phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radiopure NaI(Tl) target. The modulation amplitude of the single-hit events in the (2–6) keV energy interval is 0.0112±0.0012 cpd/kg/keV; the measured phase is 144±7 days and the measured period is 0.998±0.002 yr; values are in a good well in agreement with those expected for DM particles. No systematic or side reactions able to mimic the exploited DM signature have been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA-phase2 are outlined.

The DAMA/LIBRA experiment (∼ 250 kg of highly radio-pure NaI(Tl)) is running deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. Here we briefly recall the results obtained in its first phase of measurements (DAMA/LIBRA–phase1; total exposure: 1.04 ton × yr). DAMA/LIBRA–phase1 and the former DAMA/NaI (cumulative exposure: 1.33 ton × yr) give evidence at 9.3 σ C.L. for the presence of DM particles in the galactic halo by exploiting the model-independent DM annual modulation signature. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. At present DAMA/LIBRA–phase2 is running with increased sensitivity.

The DAMA project develops and uses new/improved low background scintillation detectors to investigate the Dark Matter (DM) particle component(s) in the galactic halo and rare processes deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N.. Here some highlights of DAMA/LIBRA (Large sodium Iodide Bulk for Rare processes) as a unique apparatus in direct DM investigation for its full sensitive mass, target material, intrinsic radio-purity, methodological approach and all the controls performed on the experimental parameters are outlined. The DAMA/LIBRA–phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) have reached a model-independent evidence at 9.3 σ C.L. for the presence of DM particles in the galactic halo exploiting the DM annual modulation signature with highly radio-pure NaI(Tl) target. Some of the perspectives of the presently running DAMA/LIBRA–phase2 are summarised and the powerful tools offered by a model independent strategy of DM investigation are pointed out.

The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA–phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA–phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radio-pure NaI(Tl) target. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. The same data of DAMA/LIBRA–phase1 have also been analyzed searching for possible DM second-order diurnal effect; at present, the DM diurnal modulation amplitude – expected because of the Earth diurnal motion – evaluated on the basis of the DAMA Dark Matter annual modulation results is below the reached experimental sensitivity. Some of the perspectives of the presently running DAMA/LIBRA–phase2 are outlined.

The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA–phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA–phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radio-pure NaI(Tl) target. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. The same data of DAMA/LIBRA–phase1 have also been analyzed searching for possible DM second-order diurnal effect; at present, the DM diurnal modulation amplitude – expected because of the Earth diurnal motion – evaluated on the basis of the DAMA Dark Matter annual modulation results is below the reached experimental sensitivity. Some of the perspectives of the presently running DAMA/LIBRA–phase2 are outlined.

The DAMA/LIBRA experiment, running at the Gran Sasso National Laboratory of the I.N.F.N. in Italy, has a sensitive mass of about 250 kg highly radiopure NaI(Tl). It is mainly devoted to the investigation of Dark Matter (DM) particles in the Galactic halo by exploiting the model independent DM annual modulation signature. The present DAMA/LIBRA experiment and the former DAMA/NaI one (the first generation experiment having an exposed mass of about 100 kg) have released so far results corresponding to a total exposure of 1.17 ton × yr over 13 annual cycles. They provide a model independent evidence of the presence of DM particles in the galactic halo at 8.9 σ C.L. on the basis of the investigated DM signature. The data of another annual cycle in the same DAMA/LIBRA running conditions are at hand. After the replacement at the end of 2012 of all the photomultipliers (PMTs) with new ones, having higher quantum efficiency, DAMA/LIBRA has entered to its phase 2; such a replacements allowed the lowering of the software energy threshold of the experiment in the present data taking. A short summary of the obtained results is presented and future perspectives of the experiment mentioned.

The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA–phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are briefly summarized. The DAMA/LIBRA–phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radio-pure NaI(Tl) target. The modulation parameters are well in agreement with those expected for DM particles. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA–phase2 are outlined.

An experiment to search for double beta processes in 106Cd by using cadmium tungstate crystal scintillator enriched in 106Cd (106CdWO4) in coincidence with the four crystals HPGe detector GeMulti is in progress at the STELLA facility of the Gran Sasso underground laboratory of INFN (Italy). The 106CdWO4 scintillator is viewed by a low-background photomultiplier tube through a lead tungstate crystal light-guide produced from deeply purified archaeological lead to suppress γ quanta from the photomultiplier tube. Here we report the first results of the experiment after 3233 hours of the data taking. A few new improved limits on double beta processes in 106Cd are obtained, in particular T1/22νεβ+ ≥ 8.4 × 1020 yr at 90% C.L.

Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search), 136Ce (2β+ candidate with one of the highest Q2β). The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides) was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to

Barium fluoride (BaF2) crystal scintillators are promising detectors to search for double beta decay processes in 130Ba (Q2β = 2619(3) keV) and 132Ba (Q2β = 844(1) keV). The 130Ba isotope is of particular interest because of the indications on 2β decay found in two geochemical experiments. The radioactive contamination of BaF2 scintillation crystal with mass of 1.714 kg was measured over 113.4 hours in a low-background DAMA/R&D set-up deep underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN (LNGS, Italy). The half-life of 212Po (present in the crystal scintillator due to contamination by radium) was estimated as T1/2 = 298.8 ± 0.8(stat.) ± 1.4(syst.) ns by analysis of the events pulse profiles.

Cadmium tungstate crystal scintillators enriched in 116Cd to 82% (116CdWO4, total mass of ≈1.2kg) are used to search for 2β decay of 116Cd deep underground at the Gran Sasso National Laboratory of the INFN (Italy). The radioactive contamination of the116CdWO4 crystals has been studied carefully to reconstruct the background of the detector. The measured half-life of 116Cd relatively to 2ν2β decay is T1/22ν2β = [2.8 ± 0.05(stat.) ± 0.4(syst.)] × 1019 yr, in agreement with the results of previous experiments. The obtained limit on the 0ν2β decay of 116Cd (considering the data of the last 8696 h run with an advanced background 0.12(2) counts/yr/kg/keV in the energy interval 2.7−2.9 MeV) is T1/2 ≥ 1.0 × 1023 yr at 90% C.L. The sensitivity of the experiment to the 0ν2β process is lim T1/2 = 3 × 1023 yr at 90% C.L. over 5 years of the measurements and it can be advanced (by further reduction of the background by a factor 3−30) to the level of lim T1/2 = (0.5-1.5) × 1024 yr for the same period of the data taking.

Some general arguments in the light of the application of the inorganic crystal scintillators in the search for rare processes are addressed. The continuous innovation provided by physics, chemistry and technology in their development allows the improvement of their performances. Also the possibility of detectors exploiting new materials is open and the further application to this field of research is promising.

Radiopure ZnWO4 crystal scintillators with mass (0.1–0.7 kg) have been developed and put inmeasurement in the Gran Sasso National Laboratories of the INFN to search for rare processes. The radioactive contamination of the crystals have been estimated and the double beta decay of zinc and tungsten isotopes was searched for, reaching a sensitivity at the level of 1018−1021 yr; in addition a new half-life limit on alpha transition of 183W to the metastable excited level of 179Hf has also been obtained. The achieved radiopurity of the ZnWO4 crystals make them very promising detectors for ββ decay investigations while their anisotropic features make them very interesting detectors to investigate dark matter particles directionality.