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The current rate of species extinction is rapidly approaching unprecedented highs, and life on Earth presently faces a sixth mass extinction event driven by anthropogenic activity, climate change, and ecological collapse. The field of conservation genetics aims at preserving species by using their levels of genetic diversity, usually measured as neutral genome-wide diversity, as a barometer for evaluating population health and extinction risk. A fundamental assumption is that higher levels of genetic diversity lead to an increase in fitness and long-term survival of a species. Here, we argue against the perceived importance of neutral genetic diversity for the conservation of wild populations and species. We demonstrate that no simple general relationship exists between neutral genetic diversity and the risk of species extinction. Instead, a better understanding of the properties of functional genetic diversity, demographic history, and ecological relationships is necessary for developing and implementing effective conservation genetic strategies.

Clinopyroxene-only thermobarometry is one of the most practical tools to reconstruct crystallization pressures and temperatures of clinopyroxenes. Because it does not require any information of coexisting silicate melt or other co-crystallized mineral phases, it has been widely used to elucidate the physiochemical conditions of crystallizing magmas. However, previously calibrated clinopyroxene-only thermobarometers display low accuracy when being applied to mafic and intermediate magmatic systems. Hence, in this study, we present new empirical nonlinear barometric and thermometric models, which were formulated to improve the performance of clinopyroxene-only thermobarometry. Particularly, a total of 559 experimental runs conducted in the pressure range of 1 bar to 12 kbar have been used for calibration and validation of the new barometric and thermometric formulation. The superiority of our new models with respect to previous ones was confirmed by comparing their performance on 100 replications of calibration and validation, and the standard error of estimate (SEE) of the new barometer and thermometer are 1.66 kbar and 36.6 ∘C, respectively. Although our new barometer and thermometer fail to reproduce the entire test dataset, which has not been used for calibration and validation, they still perform well on clinopyroxenes crystallized from subalkaline basic to intermediate magmas (i.e., basaltic, basalt-andesitic, dacitic magma systems). Thus, their applicability should be limited to basaltic, basalt-andesitic and dacitic magma systems. In a last step, we applied our new thermobarometer to several tholeiitic Icelandic eruptions and established magma storage conditions exhibiting a general consistency with phase equilibria experiments. Therefore, we propose that our new thermobarometer represents a powerful tool to reveal the crystallization conditions of clinopyroxene in mafic to intermediate magmas.

Researchers, policy makers and science communicators have become increasingly been interested in factors that affect public’s trust in science. Recently, one such potentially important driving factor has emerged, the COVID-19 pandemic. Have trust in science and other science-related beliefs changed in Germany from before to during the pandemic? To investigate this, we re-analyzed data from a set of representative surveys conducted in April, May, and November 2020, which were obtained as part of the German survey Science Barometer , and compared it to data from the last annual Science Barometer survey that took place before the pandemic, (in September 2019). Results indicate that German’s trust in science increased substantially after the pandemic began and slightly declined in the months thereafter, still being higher in November 2020 than in September 2019. Moreover, trust was closely related to expectations about how politics should handle the pandemic. We also find that increases of trust were most pronounced among the higher-educated. But as the pandemic unfolded, decreases of trust were more likely among supporters of the populist right-wing party AfD. We discuss the sustainability of these dynamics as well as implications for science communication.

Tunneling conductance among nanoparticle arrays is extremely sensitive to the spacing of nanoparticles and might be applied to fabricate ultra-sensitive sensors. Such sensors are of paramount significance for various application, such as automotive systems and consumer electronics. Here, we represent a sensitive pressure sensor which is composed of a piezoresistive strain transducer fabricated from closely spaced nanoparticle films deposited on a flexible membrane. Benefited from this unique quantum transport mechanism, the thermal noise of the sensor decreases significantly, providing the opportunity for our devices to serve as high-performance pressure sensors with an ultrahigh resolution as fine as about 0.5 Pa and a high sensitivity of 0.13 kPa −1 . Moreover, our sensor with such an unprecedented response capability can be operated as a barometric altimeter with an altitude resolution of about 1 m. The outstanding behaviors of our devices make nanoparticle arrays for use as actuation materials for pressure measurement. Designing reliable piezoresistive pressure sensors based on percolative nanoparticle (NP) arrays remains a challenge. Here, the authors propose a percolative NP array sensor deposited on a flexible membrane with ultra-high sensitivity and resolution by modifying the thickness of the membrane.

Following the popularity of smart phones and the development of mobile Internet, the demands for accurate indoor positioning have grown rapidly in recent years. Previous indoor positioning methods focused on plane locations on a floor and did not provide accurate floor positioning. In this paper, we propose a method that uses multiple barometers as references for the floor positioning of smart phones with built-in barometric sensors. Some related studies used barometric formula to investigate the altitude of mobile devices and compared the altitude with the height of the floors in a building to obtain the floor number. These studies assume that the accurate height of each floor is known, which is not always the case. They also did not consider the difference in the barometric-pressure pattern at different floors, which may lead to errors in the altitude computation. Our method does not require knowledge of the accurate heights of buildings and stories. It is robust and less sensitive to factors such as temperature and humidity and considers the difference in the barometric-pressure change trends at different floors. We performed a series of experiments to validate the effectiveness of this method. The results are encouraging.

This article explores how time interacts forcefully with the experience of living within toxic spaces. Through ethnographic research and interviews with residents of a contaminated town in Louisiana, the article unpacks the uncertain temporalities of industrial pollution and potential means of resistance. Putting Mbembe's (2003) postcolonial treatise on necropolitics in conversation with Nixon's (2011) work on slow violence, the article examines the racialized, uneven, and attritional experience of petrochemical pollution in a former plantation landscape. By exploring the necropolitics of place, the article reveals how unjust exposure to toxic chemicals creates contemporary \"death-worlds\" that are experienced in temporally uncertain and constricting ways. The oppressive nature of uncertain temporality makes the material assemblages of petrochemical infrastructure daily environmental concerns. Yet by focusing on the lived experience of communities inhabiting this toxic geography, the article notes how witnessing gradual changes to the local environment has become a barometer for perceiving chronic pollution. The idea of \"slow observation\" is posited as a useful counterpoint to slow violence and the permanent wounding of toxic pollution. Slow observation is an important aspect of living with sustained environmental brutality and offers a potential means of political resistance and doing undone environmental justice.

Calcic, igneous amphiboles are of special interest as their compositional diversity and common occurrence provide ample potential to investigate magmatic processes. But not all amphibole-based barometers lead to geologically useful information: recent and new tests reaffirm prior studies (e.g., ), indicating that amphibole barometers are generally unable to distinguish between experiments conducted at 1 atm and at higher pressures, except under highly restrictive conditions. And the fault might not lie with experimental failure. Instead, the problem may relate to an intrinsic sensitivity of amphiboles to temperature ( ) and liquid composition, rather than pressure. The exceptional conditions are those identified by : current amphibole barometers are more likely to be useful when < 800 °C and Fe# = Fe / (Fe +Mg ) < 0.65. Experimentally grown and natural calcic amphiboles are here used to investigate amphibole solid solution behavior, and to calibrate new thermometers and tentative amphibole barometers that should be applicable to igneous systems generally. Such analysis reveals that amphiboles are vastly less complex than may be inferred from published catalogs of end-member components. Most amphiboles, for example, consist largely of just three components: pargasite [NaCa (Fm Al)Si Al ], kaersutite [NaCa (Fm Ti)Si Al (OH)], and tremolite + ferro-actinolite [Ca Fm Si (OH) , where Fm = Fe+Mn+Mg]. And nearly all remaining compositionalvariation can be described with just four others: alumino-tschermakite [Ca (Fm Al )Si Al (OH) ], a Na-K-gedrite-like component [(Na, K)Fm AlSi Al (OH) ], a ferri-ferrotschermakite-like component [Ca (Fm Fe )Si Al (OH) ], and an as yet unrecognized component with 3 to 4 Al atoms per formula unit (apfu), 1 apfu each of Na and Ca, and <6 Si apfu, here termed aluminous kaersutite: NaCaFm Ti(Fe , Al) Si Al (OH). None of these components, however, are significantly pressure ( ) sensitive, leaving the Al-in-amphibole approach, with all its challenges, the best existing hope for an amphibole barometer. A new empirical barometer based on successfully differentiates experimental amphiboles crystallized at 1 to 8 kbar, at least when multiple estimates, from multiple amphibole compositions, are averaged. Without such averaging however, amphibole barometry is a less certain proposition, providing ±2 kbar precision on individual estimates for calibration data, and ±4 kbar at best for test data; independent checks on are thus needed. Amphibole compositions, however, provide for very effective thermometers, here based on , , and amphibole compositions alone, with precisions of ±30 °C. These new models, and tests for equilibrium, are collectively applied to Augustine volcano and the 2010 eruption at Merapi. Both localities reveal a significant cooling and crystallization interval (>190–270 °C) at pressures of 0.75 to 2.2 kbar at Augustine and Merapi, respectively, perhaps the likely depths from which pre-eruption magmas are stored. Such considerable intervals of cooling at shallow depths indicate that mafic magma recharge is not a proximal cause of eruption. Rather, eruption triggering is perhaps best explained by the classic “second boiling” concept, where post-recharge cooling and crystallization drive a magmatic system toward vapor saturation and positive buoyancy.

The physical and chemical properties of magma govern the eruptive style and behaviour of volcanoes. Many of these parameters are linked to the storage pressure (P) and temperature (T) of the erupted magma, and the chemistry of the melt phase (X). However, reliable single-phase thermobarometers (P, T) and chemometers (X) which can recover this information remain elusive. We present a suite of new single-phase amphibole and clinopyroxene thermobarometers and chemometers, calibrated using random forest machine learning. These calibrations are used to track the range of pre-eruptive conditions, over the course of a millennial eruptive cycle, on an island arc volcano (Mount Liamuiga, Saint Kitts, Eastern Caribbean). We unpick the recent history of Mount Liamuiga, a stratovolcano that produces a dacitic eruption from the upper crust (~ 2 kbar) prior to the Lower Mansion Series eruptive sequence. This precedes a systematic increase in the temperature of crystallisation recovered by amphibole and clinopyroxene in the middle to upper crust (1.2 ± 0.5 to 5.6 ± 2.4 kbar), which correlates with a remarkable progression of matrix plagioclase chemistry to a less-evolved (more anorthitic) composition in time. Prediction of melt chemistry (SiO 2 , Al 2 O 3 , CaO, Na 2 O, K 2 O, FeO, MgO, TiO 2 ) in equilibrium with clinopyroxene and amphibole delineate a liquid line of descent concordant with measured groundmass and whole rock chemistry. We also show that the regression strategy, as opposed to the abject insensitivity to pressure, has hindered previous calibrations of amphibole-only barometers. By applying our new calibrations, we construct a quantitative picture of the magma plumbing system beneath an arc volcano.

By monitoring the movement of the body’s centre of mass during daily-living activities, it is possible to gather information on an individual’s functional capacity and quantify key abilities such as lower limb strength, postural control and dynamic stability. To this end, a wearable inertial measurement unit attached to the lower back can offer a practical solution for analysing CoM movement in real-world conditions. However, accelerometer-based measurements are prone to drift, limiting their suitability for long-term monitoring. To mitigate these effects, miniaturized high-resolution barometers can be integrated to provide stable direct height measurements. In this study, we developed and validated a method for the reconstruction of the vertical displacement of the centre of mass during daily activities (Transition-Based Complementary Filter). The method consisted of two steps: first, the transition intervals within which vertical displacements of the centre of mass occur are identified, then, within these intervals, the complementary filter is applied to estimate the vertical displacement. Validation was carried out on twenty healthy subjects wearing an inertial unit and a barometer on the lower back, while a marker-based stereophotogrammetry system served as reference. Participants performed a series of motor tasks replicating typical home-based activities, including standing, sitting, lying, squatting, and stair climbing. The method demonstrated high accuracy, achieving a median root mean square error of 0.02 m and a median concordance correlation coefficient of 98 %. These findings underscore its robustness and clinical utility, paving the way for improved rehabilitation strategies and enhanced patient outcomes.

NASA’s Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.