We report the detection of a transiting super-Earth-sized planet (
R
= 1.39 ± 0.09
R
⊕
) in a 1.4-day orbit around L 168-9 (TOI-134), a bright M1V dwarf (
V
= 11,
K
= 7.1) located at 25.15 ± 0.02 pc. ...The host star was observed in the first sector of the Transiting Exoplanet Survey Satellite (TESS) mission. For confirmation and planet mass measurement purposes, this was followed up with ground-based photometry, seeing-limited and high-resolution imaging, and precise radial velocity (PRV) observations using the HARPS and
Magellan
/PFS spectrographs. By combining the TESS data and PRV observations, we find the mass of L 168-9 b to be 4.60 ± 0.56
M
⊕
and thus the bulk density to be 1.74
−0.33
+0.44
times higher than that of the Earth. The orbital eccentricity is smaller than 0.21 (95% confidence). This planet is a level one candidate for the TESS mission’s scientific objective of measuring the masses of 50 small planets, and it is one of the most observationally accessible terrestrial planets for future atmospheric characterization.
Various formation channels for the puzzling ultracompact dwarf galaxies (UCDs) have been proposed in the last few years. To better judge some of the competing scenarios, we present spectroscopic Fe/H ...estimates for a sample of 26 compact objects in the central region of the Fornax Cluster, covering the magnitude range of UCDs and bright globular clusters (18 mag < V < 21 mag or -13.4 mag < MV < -10.4 mag). We find a break in the metallicity distribution of compact objects at MV -11 mag (3 X 106 M): for MV < -11 mag the mean metallicity is Fe/H = -0.62 ± 0.05 dex, 0.56 ± 0.15 dex higher than the value of -1.18 ± 0.15 dex found for MV > -11 mag. This metallicity break is accompanied by a change in the size-luminosity relation for compact objects, as deduced from Hubble Space Telescope imaging: for MV < -11 mag, rh scales with luminosity, while for MV > -11 mag, rh is almost luminosity-independent. In our study we therefore assume a limiting absolute magnitude of MV = -11 mag between UCDs and globular clusters. The mean metallicity of five Fornax nucleated dwarf elliptical galaxy (dE,N) nuclei included in our study is about 0.8 dex lower than that of the UCDs, a difference significant at the 4.5 s level. This difference is marginally higher than expected from a comparison of their (V - I) colors, indicating that UCDs are younger than or at most coeval to dE,N nuclei. Because of the large metallicity discrepancy between UCDs and nuclei, we disfavor the hypothesis that most of the Fornax UCDs are the remnant nuclei of tidally stripped dE,Ns. Our metallicity estimates for UCDs are closer to but slightly below those derived for young massive clusters (YMCs) of comparable masses. We therefore favor a scenario in which most UCDs in Fornax are successors of merged YMCs produced in the course of violent galaxy-galaxy mergers. It is noted that, in contrast, the properties of Virgo UCDs are more consistent with the stripping scenario, suggesting that different UCD formation channels may dominate in either cluster.
The ascidian
Trididemnum solidum
competes for space on Caribbean reefs and is capable of overgrowing live scleractinian corals. From 2006 to 2009, we monitored over 30,000 coral colonies and ...quantified competitive interactions with this ascidian at four reef sites along the Mexican Caribbean. The total number of competitive interactions increased in time, but the mean percentage of coral colonies involved in interactions remained lower than 1% in all reefs. Bottom cover by
T. solidum
was also low (mean < 0.5%) in all reef sites in all sampling years. We conclude that during the temporal scope of our study, the overall potential effect of
T. solidum
on the dynamics of Mexican Caribbean coral populations was minimal.
We report on the first experimental demonstration of enantioselective rotational control of chiral molecules with a laser field. In our experiments, two enantiomers of propylene oxide are brought to ...accelerated unidirectional rotation by means of an optical centrifuge. Using Coulomb explosion imaging, we show that the centrifuged molecules acquire preferential orientation perpendicular to the plane of rotation, and that the direction of this orientation depends on the relative handedness of the enantiomer and the rotating centrifuge field. The observed effect is in agreement with theoretical predictions and is reproduced in numerical simulations of the centrifuge excitation followed by Coulomb explosion of the centrifuged molecules. The demonstrated technique opens new avenues in optical enantioselective control of chiral molecules with a plethora of potential applications in differentiation, separation, and purification of chiral mixtures.
Fire can affect soil properties depending on a number of factors including fire severity and soil type. Aggregate stability (AS) refers to soil structure resilience in response to external mechanical ...forces. Many authors consider soil aggregation to be a parameter reflecting soil health, as it depends on chemical, physical and biological factors. The response of AS to forest fires is complex, since it depends on how fire has affected other related properties such as organic matter content, soil microbiology, water repellency and soil mineralogy. Opinions differ concerning the effect of fire on AS. Some authors have observed a decrease in AS in soils affected by intense wildfire or severe laboratory heating. However, others have reported increases. We provide an up to date review of the research on this topic and an analysis of the causes for the different effects observed. The implications for soil system functioning and for the hydrology of the affected areas are also discussed. Generally, low severity fires do not produce notable changes in AS, although in some cases an increase has been observed and attributed to increased water repellency. In contrast, high severity fires can induce important changes in this property, but with different effects depending on the type of soil affected. The patterns observed can vary from a disaggregation as a consequence of the organic matter destruction, to a strong aggregation if a recrystallization of some minerals such as Fe and Al oxyhydroxides occurs when they are present in sufficient quantities in the soil, after exposure to high temperatures. Because of the complexity of the different possible effects and reasons for the potential changes in the fire-affected soil aggregates, the inclusion of other parameters in the studies is necessary to understand the results. The suggested parameters to include in the examination of AS are: soil organic matter, microbial biomass, water repellency, texture, aggregate size distribution, together with accurate ways of estimating fire severity. More research is needed on what implications there are for soil system functioning with the changes suffered by aggregates after fire. Studies including measurements at very different scales: from AS measurements in the laboratory to erosion rates measured at pedon, slope and catchment scales are also necessary.
► The different patterns of aggregation observed in burned soils are reviewed and analyzed. ► Different responses to fire result from different combination of involved factors. ► Main factors are: fire severity, water repellency, mineralogy, organic matter and microbiology. ► More research is needed on what implications have fire effects on aggregation for soil system functioning.
•Polystyrene nanoparticles (PS NPs) crossed the zebrafish chorion.•PS NPs accumulated in numerous organs during development.•Bradycardia and hypoactivity were observed following exposure to PS NPs.
...Plastic pollution is a critical environmental concern and comprises the majority of anthropogenic debris in the ocean, including macro, micro, and likely nanoscale (less than 100nm in at least one dimension) plastic particles. While the toxicity of macroplastics and microplastics is relatively well studied, the toxicity of nanoplastics is largely uncharacterized. Here, fluorescent polystyrene nanoparticles (PS NPs) were used to investigate the potential toxicity of nanoplastics in developing zebrafish (Danio rerio), as well as to characterize the uptake and distribution of the particles within embryos and larvae. Zebrafish embryos at 6h post-fertilization (hpf) were exposed to PS NPs (0.1, 1, or 10ppm) until 120 hpf. Our results demonstrate that PS NPs accumulated in the yolk sac as early as 24 hpf and migrated to the gastrointestinal tract, gallbladder, liver, pancreas, heart, and brain throughout development (48–120 hpf). Accumulation of PS NPs decreased during the depuration phase (120–168 hpf) in all organs, but at a slower rate in the pancreas and gastrointestinal tract. Notably, exposure to PS NPs did not induce significant mortality, deformities, or changes to mitochondrial bioenergetics, but did decrease the heart rate. Lastly, exposure to PS NPs altered larval behavior as evidenced by swimming hypoactivity in exposed larvae. Taken together, these data suggest that at least some nanoplastics can penetrate the chorion of developing zebrafish, accumulate in the tissues, and affect physiology and behavior, potentially affecting organismal fitness in contaminated aquatic ecosystems.
Many children in need do not receive the psychoeducational evaluation services they need, with an estimated 15% of all students struggling with attentional or learning difficulties that are ...unassessed, and thus unaddressed, during "normal" times. Such evaluations have largely halted during the COVID-19 crisis, with questionable psychometrics of usable measures and clinicians largely unprepared to administer them. Remote, online psychoeducational evaluations have the potential to decrease this access problem by allowing for evaluations to continue during the crisis, as well as redistributing (geographically and potentially socioeconomically) evaluators to populations disproportionately without access. The present study evaluated the equivalence of a remote, online administration procedure for the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) with traditional, in-person administration. Results revealed no significant differences-and, therefore, method effects-between the full-scale IQ and index scores between the administration procedures. One subtest did reveal a significant method effect, with children performing more poorly on the remote, online version of the test. Although imperfect, the remote, online procedure is a viable alternative for the traditional, in-person administration of the WISC-V, especially during this time of crisis.
Public Significance Statement
This article evaluates whether the Wechsler Intelligence Scale for Children, Fifth Edition, given in a remote, online format produces equivalent results as the traditional, in-person administration of the test, as it was developed and meant to be used. The findings reveal how evaluators can use the test in a telehealth context, to continue cognitive evaluations during the COVID-19 crisis, as well as ongoing afterward for students without access to evaluation services.
Abstract
We report the first discovery of a multi-planetary system by the HATSouth network, HATS-59b,c, a planetary system with an inner transiting hot Jupiter and an outer cold massive giant planet, ...which was detected via radial velocity. The inner transiting planet, HATS-59b, is on an eccentric orbit with
, orbiting a
mag solar-like star (
=
and
) with a period of
days. The outer companion, HATS-59c is on a circular orbit with
and a period of 1422 ± 14 days. The inner planet has a mass of
and a radius of
, yielding a density of
. Unlike most planetary systems that include only a single hot Jupiter, HATS-59b,c includes, in addition to the transiting hot Jupiter, a massive outer companion. The architecture of this system is valuable for understanding planet migration.
In certain regions of the United States, there has been a dramatic proliferation of trauma centers. The goal of our study was to evaluate transport times during this period of trauma center ...proliferation.
Aggregated data summarizing level I trauma center admissions in Arizona between 2009 and 2018 were provided to our institution by the Arizona Department of Health Services. We evaluated patient demographics, transport times, and injury severity for both rural and urban injuries.
Data included statistics summarizing 266,605 level I trauma admissions in the state of Arizona. The number of state-designated trauma centers during this time increased from 14 to 47, with level I centers increasing from 8 to 13. Slight decreases in mean Injury Severity Score (rural, 9.4 vs. 8.4; urban, 7.9 vs. 7.0) were observed over this period. Median transport time for cases transported from the injury scene directly to a level I center remained stable in urban areas at 0.9 hours in both 2009 and 2018. In rural areas, transport times for these cases were approximately double but also stable, with median times of 1.8 and 1.9 hours. Transport times for cases requiring interfacility transfer before admission at a level I center increased by 0.3 hours for urban injuries (5.3-5.6 hours) and 0.9 hours for rural injuries (5.6-6.5 hours).
Despite the threefold increase in the number of state-designated trauma centers, transport time has not decreased in urban or rural areas. This finding highlights the need for regulatory oversight regarding the number and geographic placement of state-designated trauma centers.
Care management, level IV, Epidemiological, level III.
Visuomotor adaptation has been thought to be an implicit process that results when a sensory-prediction error signal is used to update a forward model. A striking feature of human competence is the ...ability to receive verbal instructions and employ strategies to solve tasks; such explicit processes could be used during visuomotor adaptation. Here, we used a novel task design that allowed us to obtain continuous verbal reports of aiming direction while participants learned a visuomotor rotation. We had two main hypotheses: the contribution of explicit learning would be modulated by instruction and the contribution of implicit learning would be modulated by the form of error feedback. By directly assaying aiming direction, we could identify the time course of the explicit component and, via subtraction, isolate the implicit component of learning. There were marked differences in the time courses of explicit and implicit contributions to learning. Explicit learning, driven by target error, was achieved by initially large then smaller explorations of aiming direction biased toward the correct solution. In contrast, implicit learning, driven by a sensory-prediction error, was slow and monotonic. Continuous error feedback reduced the amplitude of explicit learning and increased the contribution of implicit learning. The presence of instruction slightly increased the rate of initial learning and only had a subtle effect on implicit learning. We conclude that visuomotor adaptation, even in the absence of instruction, results from the interplay between explicit learning driven by target error and implicit learning of a forward model driven by prediction error.
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