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Hurricane Laura made landfall in southwestern Louisiana in August 2020 while the world was several months into the COVID-19 pandemic. In the present research, we examined pandemic precautionary behaviors in a sample of adults who varied in exposure and damage due to Hurricane Laura, a destructive Category 4 hurricane. A total of 127 participants responded to an online survey that assessed pandemic worry and precautionary behaviors, hurricane exposure and damage, and health-related quality of life. We found that Hurricane Laura victims neglected pandemic precautionary behaviors at significantly higher levels in the weeks immediately following Hurricane Laura than did indirectly impacted control participants, although the two comparison groups did not differ in COVID-19 worry or adherence to precautionary pandemic behavior 14–22 months after Hurricane Laura made landfall. Older age was negatively correlated with COVID-19 worry prior to Hurricane Laura, which was unexpected given that older people in general were more vulnerable to COVID-19 by their membership in a high-risk group. Future directions for research on post-disaster vulnerabilities during a global pandemic are discussed.

The DARWIN observatory is a proposed next-generation experiment with 40 tonnes of liquid xenon as an active target in a time projection chamber. To study challenges related to the construction and operation of a multi-tonne scale detector, we have designed and constructed a vertical, full-scale demonstrator for the DARWIN experiment at the University of Zurich. Here, we present the first results from a several-months run with 343 kg of xenon and electron drift lifetime and transport measurements with a 53 cm tall purity monitor immersed in the cryogenic liquid. After 88 days of continuous purification, the electron lifetime reached a value of ( 664 ± 23 ) μ s . We measured the drift velocity of electrons for electric fields in the range (25–75) V/cm, and found values consistent with previous measurements. We also calculated the longitudinal diffusion constant of the electron cloud in the same field range, and compared with previous data, as well as with predictions from an empirical model.

The DARWIN observatory is a proposed next-generation experiment to search for particle dark matter and for the neutrinoless double beta decay of$$^{136}$$136 Xe. Out of its 50 t total natural xenon inventory, 40 t will be the active target of a time projection chamber which thus contains about 3.6 t of$$^{136}$$136 Xe. Here, we show that its projected half-life sensitivity is$$2.4\\times {10}^{27}\\,{\\hbox {year}}$$2.4 × 10 27 year , using a fiducial volume of 5 t of natural xenon and 10 year of operation with a background rate of less than 0.2 events/(t $$\\cdot $$·  year) in the energy region of interest. This sensitivity is based on a detailed Monte Carlo simulation study of the background and event topologies in the large, homogeneous target. DARWIN will be comparable in its science reach to dedicated double beta decay experiments using xenon enriched in$$^{136}$$136 Xe.

Rapid eye movements (REM) are characteristic of the eponymous phase of sleep, yet the underlying motor commands remain an enigma. Here, we identified a cluster of Calbindin-D28K-expressing neurons in the Nucleus papilio (NP Calb ), located in the dorsal paragigantocellular nucleus, which are active during REM sleep and project to the three contralateral eye-muscle nuclei. The firing of opto-tagged NP Calb neurons is augmented prior to the onset of eye movements during REM sleep. Optogenetic activation of NP Calb neurons triggers eye movements selectively during REM sleep, while their genetic ablation or optogenetic silencing suppresses them. None of these perturbations led to a change in the duration of REM sleep episodes. Our study provides the first evidence for a brainstem premotor command contributing to the control of eye movements selectively during REM sleep in the mammalian brain. Rapid eye movement (REM) sleep is a sleep phase characterised by random eye movements for which the underlying motor commands are yet to be revealed. The authors describe that a cluster of medulla oblongata neurons in the Nucleus papilio contributes to the control of eye movements during REM sleep.

In West Africa, lakes and reservoirs play a vital role as they are critical resources for drinking water, livestock, irrigation, and fisheries. Given the scarcity of in‐situ data, satellite remote sensing is an important tool for monitoring lake volume changes in this region. Several methods have been developed to do this using water height‐area‐volume relationships, but few publications have compared their performances over small and medium‐sized shallow lakes. In this work we compare four methods based on recent data from high‐resolution optical imagery and radar and lidar altimetry over 16 lakes in the Central Sahel, with areas between 0.22 km2${\\text{km}}^{2}$and 21 km2${\\text{km}}^{2}$ . All methods show consistent results and are generally in good agreement with in‐situ data in terms of accuracy (Root Mean Squared Error below 0.42 m for heights and Normalized Root Mean Squared Error below 13% for volumes). The precision of the estimated water height is about 0.20 m for Pleiades Digital Surface Models (DSMs) and less than 0.13 m for the other methods. Inherent limitations such as DSM quality, temporal coverage of DSM and lidar data, and spatial coverage of radar altimetry data are identified. Overall, fine shape patterns are consistently observed over small height amplitudes, highlighting the ability to monitor shallow lakes with non‐linear height‐area relationship. Finally, we show that combining lidar and radar altimetry‐based methods provides estimates of volume changes over the different water bodies of the study region accurate enough to monitor seasonal, interannual, and long‐term variability. Key Points Height‐area‐volume relationships of small and medium‐sized shallow lakes are estimated using recent remote sensing data based methods Radar and lidar altimetry coupled to Sentinel‐2 imagery, and Pleiades Digital Surface Models perform well against in‐situ data Inherent limits, spatio‐temporal coverage, and data accessibility of each method are identified and discussed

For the first time, a small dual-phase (liquid/gas) xenon time projection chamber was equipped with a top array of silicon photomultipliers for light and charge readout. Here we describe the instrument in detail, as well as the data processing and the event position reconstruction algorithms. We obtain a spatial resolution of ∼ 1.5 mm in the horizontal plane. To characterise the detector performance, we show calibration data with internal 83 m Kr and 37 Ar sources, and we detail the production of the latter as well as its introduction into the system. We finally compare the observed light and charge yields down to electronic recoil energies of 2.82 keV to predictions based on NEST v2.0.

Our two main goals are first to evaluate the resilience of the boreal forest according to latitude across the closed-crown forest zone using the post-disturbance distribution and cover of lichen woodlands and closed-crown forests as a metric, and second to identify the disturbance factors responsible for the regeneration and degradation of the closed-crown forest according to latitude since the 1950s. The study area extends between 70°00' and 72°00' W and throughout the closed-crown forest zone, from its southern limit near 47°30' N to its northern limit at the contact with the lichen woodland zone at around 52°40' N. Recent (1972-2002) and old (1954-1956) aerial photos were used to map the distribution of lichen woodlands across the closed-crown forest zone. Forest disturbances such as fire, spruce budworm (Choristoneura fumiferana (Clemens)) outbreak, and logging were recorded on each set of aerial photos. Each lichen woodland and stand disturbance was validated by air-borne surveys and digitized using GIS software. Over the last 50 years, the area occupied by lichen woodlands has increased according to latitude; that is, 9% of the area that was occupied by closed-crown forests has shifted to lichen woodlands. Although logging activities have been concentrated in the same areas during the last 50 years, the area covered by logging has increased significantly. Outbreaks by the spruce budworm occurred predominantly in the southern (47°30' N to 48°30' N) and central (48°53' N to 50°42' N) parts of the study area, where balsam fir stands are extensive. In the northern part of the study area (51°-52°40' N), extensive fires affected the distribution and cover of closed-crown forests and lichen woodlands. Over the last 50 years, the area occupied by closed-crown forests has decreased dramatically, and the ecological conditions that allow closed-crown forests to establish and develop are currently less prevalent. Fire is by far the main disturbance, reducing the ability of natural closed-crown forests to self-regenerate whatever the latitude. Given the current biogeographical shift from dense to open forests, the northern part of the closed-crown forest zone is in a process of dramatic change towards the dominance of northern woodlands.

Two deep wells were drilled at Rittershoffen (Alsace, France) to produce high-temperature fluids to supply heat to a biorefinery. The GRT-2 production well was drilled to a depth of 3196 m MD and was deviated to target a permeable local fault in the granitic basement buried beneath a thick sedimentary cover. The objective of this study is to better understand the permeability of fractured reservoirs within crystalline rocks, focusing on the production well GRT-2. Based on a petrographic and mineralogical analysis of cutting samples, several granitic facies associated with hydrothermal alteration were identified on the basis of the amounts of illite, chlorite, anhydrite, secondary geodic quartz, and oxides. These observations were correlated with various geological and geophysical datasets (gamma ray, porosity, density, electrical resistivity, caliper, borehole image logs, temperature, rate of penetration, and mud losses) to localize and identify permeable fracture zones. In sections where acoustic image logs were not available, such as in the deepest part of the well, the geometries of the fracture zones were interpreted from an oriented caliper log. The caliper log interpretation detected one-third of the fractures detected by acoustic image logs. However, two major fracture sets striking N–S and dipping eastward or westward were observed. Furthermore, a synthetic resistivity log that fits the measured resistivity log relatively well was built using the Archie and Waxman and Smits models. This approach is a proxy for estimating the porosity and the mineralogical changes based on the cation exchange capacity, which is controlled by the chlorite/illite ratio, derived from electrical logs in granitic formations. The correlation of all these results allowed the identification of a resistivity signature of a permeable fracture zone that spatially fits with the temperature signature. The major contribution of this study is the identification of a hierarchy of permeable fractures based on petrophysical signatures. The geophysical signature of fracture zones with low residual permeability exhibits a broad depth extent, whereas the geophysical signature of a highly permeable fracture zone is more localized. Past hydrothermal circulation has enlarged the altered and porous zones around open fractures, and in some cases, intense illitization has plugged these fracture zones and reduced their permeabilities.

We correct an overestimation of the production rate of 137 Xe in the DARWIN detector operated at LNGS. This formerly dominant intrinsic background source is now at a level similar to the irreducible background from solar 8 B neutrinos, thus unproblematic at the LNGS depth. The projected half-life sensitivity for the neutrinoless double beta decay ( 0 ν β β ) of 136 Xe improves by 22 % compared to the previously reported number and is now T 1 / 2 0 ν = 3.0 × 10 27 yr (90% C.L.) after 10 years of DARWIN operation.

We correct an overestimation of the production rate of$$^{137}$$137 Xe in the DARWIN detector operated at LNGS. This formerly dominant intrinsic background source is now at a level similar to the irreducible background from solar$$^8$$8 B neutrinos, thus unproblematic at the LNGS depth. The projected half-life sensitivity for the neutrinoless double beta decay ($$0\\nu \\beta \\beta $$0 ν β β ) of$$^{136}$$136 Xe improves by$$22\\%$$22 % compared to the previously reported number and is now$$T^{0\\nu }_{1/2}= {3.0\\times 10^{27}} \\hbox { yr}$$T 1 / 2 0 ν = 3.0 × 10 27 yr (90% C.L.) after 10 years of DARWIN operation.