A
bstract
Neutrinoless double-beta decay is a key process in particle physics. Its experimental investigation is the only viable method that can establish the Majorana nature of neutrinos, providing ...at the same time a sensitive inclusive test of lepton number violation. CROSS (Cryogenic Rare-event Observatory with Surface Sensitivity) aims at developing and testing a new bolometric technology to be applied to future large-scale experiments searching for neutrinoless double-beta decay of the promising nuclei
100
Mo and
130
Te. The limiting factor in large-scale bolometric searches for this rare process is the background induced by surface radioactive contamination, as shown by the results of the CUORE experiment. The basic concept of CROSS consists of rejecting this challenging background component by pulse-shape discrimination, assisted by a proper coating of the faces of the crystal containing the isotope of interest and serving as energy absorber of the bolometric detector. In this paper, we demonstrate that ultra-pure superconductive Al films deposited on the crystal surfaces act successfully as pulse-shape modifiers, both with fast and slow phonon sensors. Rejection factors higher than 99.9% of
α
surface radioactivity have been demonstrated in a series of prototypes based on crystals of Li
2
MoO
4
and TeO
2
. We have also shown that point-like energy depositions can be identified up to a distance of
∼
1 mm from the coated surface. The present program envisions an intermediate experiment to be installed underground in the Canfranc laboratory (Spain) in a CROSS-dedicated facility. This experiment, comprising
∼
3
×
10
25
nuclei of
100
Mo, will be a general test of the CROSS technology as well as a worldwide competitive search for neutrinoless double-beta decay, with sensitivity to the effective Majorana mass down to 70 meV in the most favorable conditions.
This study presents a method based on retrofitted low-cost and easy to implement tracking devices, used to monitor the whole harvesting process in viticulture, to map yield andharvest quality ...parameters in viticulture. The method consists of recording the geolocation of all the machines (harvest trailers and grape harvester) during the harvest to spatially reallocate production parameters measured at the winery. The method was tested on a vineyard of 30 ha during the whole 2022 harvest season. It has identified harvest sectors (HS) associated with measured production parameters (grape mass and harvest quality parameters: sugar content, total acidity, pH, yeast assimilable nitrogen, organic nitrogen) and calculated production parameters (potential alcohol of grapes, yield, yield per plant) over the entire vineyard. The grape mass was measured at the vineyard cellar or at the winegrowing cooperative by calibrated scales. The harvest quality parameters were measured on grape must samples in a commercial laboratory specialized in oenological analysis and using standardized protocols. Results validate the possibility of making production parameters maps automatically solely from the time and location records of the vehicles. They also highlight the limitations in terms of spatial resolution (the mean area of the HS is 0.3 ha) of the resulting maps which depends on the actual yield and size of harvest trailers. Yield per plant and yeast assimilable nitrogen maps have been used, in collaboration with the vineyard manager, to analyze and reconsider the fertilization process at the vineyardscale, showing the relevance of the information.
Context
Cities are a challenging habitat for obligate nocturnal mammals because of the ubiquitous use of artificial light at night (ALAN). How nocturnal animals move in an urban landscape, ...particularly in response to ALAN is largely unknown.
Objectives
We studied the movement responses, foraging and commuting, of common noctules (
Nyctalus noctula
) to urban landscape features in general and ALAN in particular.
Methods
We equipped 20 bats with miniaturized GPS loggers in the Berlin metropolitan area and related spatial positions of bats to anthropogenic and natural landscape features and levels of ALAN.
Results
Common noctules foraged close to ALAN only next to bodies of water or well vegetated areas, probably to exploit swarms of insects lured by street lights. In contrast, they avoided illuminated roads, irrespective of vegetation cover nearby. Predictive maps identified most of the metropolitan area as non-favoured by this species because of high levels of impervious surfaces and ALAN. Dark corridors were used by common noctules for commuting and thus likely improved the permeability of the city landscape.
Conclusions
We conclude that the spatial use of common noctules, previously considered to be more tolerant to light than other bats, is largely constrained by ALAN. Our study is the first individual-based GPS tracking study to show sensitive responses of nocturnal wildlife to light pollution. Approaches to protect urban biodiversity need to include ALAN to safeguard the larger network of dark habitats for bats and other nocturnal species in cities.
This paper presents a three-dimensional constitutive model for natural clay that includes creep, anisotropy and structure, as well as a theoretical means to estimate the range for anisotropy- and ...structure-related parameters, as needed for parameter optimisation. Creep-SCLAY1S is an extension of the Creep-SCLAY1 model proposed by Sivasithamparam et al. (Comput Geotech 69:46–57,
2015
) which includes the effects of bonding and destructuration. The model needs 14 model parameters, of which five are similar to those used in the modified Cam–Clay model. A method is developed to quantify the range for the three parameters related to structure and anisotropy that cannot be derived directly from experimental data. The theoretically derived range compares favourably with the values found in the literature. As a result, the model now can be used with more confidence, enabling sensitivity analysis and systematic parameter derivation with optimisation techniques.
Constitutive models for soft soils require a large number of parameters to model the complex material response. One set of parameters should capture the soil response for various laboratory & in situ ...stress paths. This requires a new method to calibrate a consistent set of model parameters using test data from different load paths of classic geomechanical tests. The feasibility of the proposed method is demonstrated with the recently developed CREEP-SCLAY1S model. After a sensitivity analysis that highlights the model parameters for optimisation, an optimisation process for two different configurations is designed. The latter is successfully verified against artificially generated laboratory data.
Stoichiometric hydroxyapatite (HAP) is a prominent biomaterial, notably used as coating on metal bone prostheses. High chemical purity and a specific particle size distribution are the main ...properties for such an application. Based on industrial practice, a reference synthesis was first performed in a lab-scale stirred reactor. Improvements were then suggested by varying the physicochemical and hydrodynamic conditions. The shear rate within the reactor, characterized by the mean Kolmogorov micro-scale, has a strong impact on the final agglomerate size distribution. By maintaining a rather high mixing rate and a high temperature, the duration of the synthesis can be reduced considerably without affecting the HAP purity provided the pH is properly regulated. This consists of imposing acidic conditions during a short period just after the initial formation of large aggregates and then setting the pH at above 7.5 to ensure the production of pure stoichiometric HAP.
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•The shear rate mainly impacts the particle size distribution of synthesized HAP.•Pure HAP can be produced at 75 °C ensuring a relevant pH regulation.•Under specific physico-chemical conditions, maturation has only a small effect on HAP.
•Compliance with recommendations on Hand Hygiene varies in the different areas.•Compliance with recommendations on Hand Hygiene can and should be improved.•One modifiable associated factor is the ...indications “after an activity has been performed.”•Other modifiable associated factors is the availability of pocket-size alcohol-based solution.
The objective is to know the evolution of the Degree of Compliance with Recommendations (DCR) on hand hygiene (HH) and its associated factors in the pediatric care areas (PCAs) of a tertiary hospital.
Observational, cross-sectional study, repeated over time, with direct observation of the DCR on HH during the daily activity of health care workers. Over 13 years, 9226 HH opportunities were observed. Associations between DCR, PCA and other variables (eg, age, sex, and professional position) were examined using χ² and adjusted odds ratios (aOR) with 95% confidence intervals (CI).
DCR on HH in 9 PCAs was 64.3% (95% CI, 63.3-65.3), and in the group of non-pediatric areas it was 49.6% (95% CI, 49.1-50.1). The areas with the highest degree of compliance were Oncology 72.8% (95% CI, 69.2-76.4), Neonatology 73.2% (95% CI, 71.3-75.1), and Neonatal intensive care unit 70.0% (95% CI, 67.5-72.6). These were the areas with the strongest association with HH compliance, with aOR:2.8 (95% CI, 2.2-3.6); aOR, 3.0 (95% CI, 2.6-3.6) aOR:2.6 (95% CI, 2.1-3.1), respectively. Other associated factors were the indications “after an activity,” aOR, 1.6 (95% CI, 1.5-1.8) and the availability of pocket-size alcohol-based solution, aOR, 2.1(95% CI, 1.9-2.3).
The DCR on HH in PCAs is higher than in other areas, although there is still margin for improvement. We have identified modifiable factors that have an independent association with HH compliance in PCAs. Focusing on modifiable factors will increase compliance with HH with the ultimate goal of reducing healthcare associated infections.
We investigated the behavior of a water liquid bridge formed between two grains. We mainly focused on tensile tests with suction control (capillary pressure). Theoretical and experimental studies are ...compared. A new experimental device involving suction control of the liquid bridge was developed specifically for this kind of test. Most of the liquid bridge variables and characteristics were measured by image analysis (gorge radius, volume, contact angles, filling angles). Capillary force was measured by differential weighting. Experimental conditions allows us to avoid viscous effects. Our experimental results were close to Young-Laplace equation solutions. The “gorge method”, commonly used for calculating the capillary force, was also validated by our experiments. Liquid bridge rupture was studied and a new rupture criterion is proposed. This criterion depends on the grain radius, contact angle, surface tension and suction and was in agreement with the experimental results.
We investigate the water distribution and the link between suction and water content in granular media. Firstly, we examine the effect of suction on the shape and the volume of the liquid bridge by ...four different methods. Method I is based on the local expression of the capillary force coupled with the gorge method and Method II is based on the Laplace law. These two methods use the toroidal approximation. Methods III and IV are based on the integration of the differential equation that defines the liquid bridge shape (established from the Laplace law). This local behaviour is then used in a discrete element study of a sample composed of several thousands of grains. We focus our study on the pendular state. A liquid film around the grains involving the continuity of the liquid phase is assumed. The water distribution and the water content associated with a given suction are calculated. Then retention curves of the granular media are built. A parametric study is made to bring to light the effect of macroscopic parameters (grain-size distribution) and physical parameters (liquid/air surface tension and contact angle) on the water retention curve. Finally, numerical data are compared to experimental results.
Water retention curve is investigated in granular media. The local behavior of a liquid bridge is studied by four differents methods and is then used to modelise the water retention curve of a macroscopic sample realised by the discrete element method. These numerical water retention curves are finally compared to experimental results on samples composed of glass beads.
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In preparation for the CROSS experiment to search fordouble-beta (2β) decay of 100Mo, we upgraded alow-background facility at the Canfranc underground laboratory(Spain) by installing a magnetic ...damping-based detector suspensioninside a pulse-tube cryostat. We tested the suspension inlow-temperature (15 mK) measurements with two scintillatingbolometers made of large-volume crystals of 116CdWO4(reference of the set-up) and Li2MoO4 (R&D of the CLYMENEproject in view of the CUPID 2β experiment), each coupled to athin Ge bolometric light detector. Despite the evidence of aresidual pulse-tube-induced noise, picked up by cabling, we achievedhigh performance with all tested devices. In particular, the energyresolution for 2615 keV γ-ray measured with both116CdWO4 and Li2MoO4 bolometers is ∼6 keV FWHM,among the best-reported results for thermal detectors based on suchcompounds representing a great interest to searches for 2βdecay in 116Cd (Q-value is 2813 keV) and 100Mo(3034 keV) respectively. Highly efficient particle identification(α vs. β/γ) is achieved also with thescintillating bolometer made of a low light yield crystal(Li2MoO4), thanks to the low noise (10 eV RMS) exhibited bythe light detector exploiting the Neganov-Trofimov-Luke effect forsignal amplification. We also found a rather high level ofradiopurity in the Li2MoO4 crystal; only traces of 210Poand 226Ra were detected (∼0.1 mBq/kg each), while the228Th activity is expected to be at least an order of magnitudelower, as well as a 40K activity is below 6 mBq/kg.
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