Characterization of Microplastics in the Atmosphere

Microplastics (MPs) are defined as small fragments of plastic or synthetic polymer material that are less than 5mm in size. Previous research has primarily focused on MPs in marine and coastal environments; however, characterization of MPs in the atmosphere has been limited. The goal of this study is to investigate MPs in the atmosphere, i.e., their composition, origin, and transport, due to the uncertainties associated with the impacts of MPs on human health upon inhalation. Active and passive sampling is conducted at two diverse locations: Embry-Riddle Aeronautical University in Daytona Beach, Florida and Colorado State University in Fort Collins, Colorado. Active sampling entails using the Tisch High Volume Air Sampler, to collect MPs on filters which are collected daily. On the other hand, passive sampling utilizes a setup devised to hold the filter to collect MPs, on a weekly basis. Post sampling procedures involve submerging the filters in 30% hydrogen peroxide to eliminate any organic material and to ensure that only MPs are being analyzed followed by vacuum filtration where the MPs are transferred to a 10 filter for visual analysis. Optical characterization takes place using a ZEISS Axioscope 7 compound microscope to determine the size distribution of these particles. Fourier transform infrared (FTIR) spectroscopy will be utilized to investigate the chemical properties of MPs. This study has implications for the effects of MPs on human health via inhalation, as well as their effects on water bodies and soil upon deposition

Probing the atmosphere of a sub-Jovian planet orbiting a cool dwarf

We derive the 0.01 $\mu$m binned transmission spectrum, between 0.74 and 1.0 $\mu$m, of WASP-80b from low resolution spectra obtained with the FORS2 instrument attached to ESO's Very Large Telescope. The combination of the fact that WASP-80 is an active star, together with instrumental and telluric factors, introduces correlated noise in the observed transit light curves, which we treat quantitatively using Gaussian Processes. Comparison of our results together with those from previous studies, to theoretically calculated models reveals an equilibrium temperature in agreement with the previously measured value of 825K, and a sub-solar metallicity, as well as an atmosphere depleted of molecular species with absorption bands in the IR ($\gg 5\sigma$). Our transmission spectrum alone shows evidence for additional absorption from the potassium core and wing, whereby its presence is detected from analysis of narrow 0.003 $\mu$m bin light curves ($\gg 5\sigma$). Further observations with visible and near-UV filters will be required to expand this spectrum and provide more in-depth knowledge of the atmosphere. These detections are only made possible through an instrument-dependent baseline model and a careful analysis of systematics in the data.Comment: 13 pages, 11 figures, 3 tables. Accepted for publication in MNRA

A CHEOPS Search for Massive, Long-period Companions to the Warm Jupiter K2-139 b

K2-139 b is a warm Jupiter with an orbital period of 28.4 days, but only three transits of this system have previously been observed–in the long-cadence mode of K2–limiting the precision with which the orbital period can be determined and future transits predicted. We report photometric observations of four transits of K2-139 b with ESA's CHaracterising ExOPlanet Satellite (CHEOPS), conducted with the goal of measuring the orbital obliquity via spot-crossing events. We jointly fit these CHEOPS data alongside the three previously-published transits from the K2 mission, considerably increasing the precision of the ephemeris of K2-139 b. The transit times for this system can now be predicted for the next decade with a 1σ precision less than 10 minutes, compared to over one hour previously, allowing the efficient scheduling of observations with Ariel. We detect no significant deviation from a linear ephemeris, allowing us to exclude the presence of a massive outer planet orbiting with a period less than 150 days, or a brown dwarf with a period less than one year. We also determine the scaled semimajor axis, the impact parameter, and the stellar limb darkening with improved precision. This is driven by the shorter cadence of the CHEOPS observations compared to that of K2, and validates the subexposure technique used for analyzing long-cadence photometry. Finally, we note that the stellar spot configuration has changed from the epoch of the K2 observations; unlike the K2 transits, we detect no evidence of spot-crossing events in the CHEOPS data

Characterization of Microplastics in the Atmosphere

For the purposes of this research, microplastics (MPs) can be defined as small fragments of plastic or synthetic polymer material that are less than 5mm in size. The goal of this study is to investigate MPs in the atmosphere. Previous research has primarily focused on MPs in marine and coastal environments; however, we are directing our attention to the atmospheric presence of MPs. This is due to the uncertainties associated with the impacts of MPs on human health upon inhalation. By the means of active and passive sampling, we aim to determine the atmospheric transport of MPs operating from the Embry-Riddle Aeronautical University at the Daytona Beach Campus. Active sampling entails using the Tisch High Volume Air Sampler, which will be collected daily. On the other hand, passive sampling utilizes a setup devised to hold the filter to collect MPs, this will be collected weekly. From this point, the MPs will be isolated and analyzed under a ZEISS Axioscope 7 compound microscope to determine the size of the microplastic particles. Fourier transform infrared (FTIR) spectroscopy will be utilized to investigate chemical properties of MPs. Utilizing these methods, we will obtain a thorough understanding of the composition and origin of these atmospheric particles. To further assess the effect of weather conditions on the transportation of MPs in the atmosphere, this work will be conducted seasonally. This study has implications for the effects of MPs on human health via inhalation, as well as their effects on water bodies and soil upon deposition

The Apparent Tidal Decay of WASP-4 b Can Be Explained by the Rømer Effect

Tidal orbital decay plays a vital role in the evolution of hot Jupiter systems. As of now, this has only been observationally confirmed for the WASP-12 system. There are a few other candidates, including WASP-4 b, but no conclusive result could be obtained for these systems as of yet. In this study, we present an analysis of new TESS data of WASP-4 b together with archival data, taking the light–time effect (LTE) induced by the second planetary companion into account as well. We make use of three different Markov chain Monte Carlo models: a circular orbit with a constant orbital period, a circular orbit with a decaying orbit, and an elliptical orbit with apsidal precession. This analysis is repeated for four cases. The first case features no LTE correction, with the remaining three cases featuring three different timing correction approaches because of the large uncertainties of the ephemeris of planet c. Comparison of these models yields no conclusive answer to the cause of WASP-4 b’s apparent transit timing variations. A broad range of values of the orbital decay and apsidal precession parameters are possible, depending on the LTE correction. However, the LTE caused by planet c can explain on its own—in full—the observed transit timing variations of planet b, with no orbital decay or apsidal precession being required at all. This work highlights the importance of continued photometric and spectroscopic monitoring of hot Jupiters

The Orbit of Warm Jupiter WASP-106 b is aligned with its Star

Understanding orbital obliquities, or the misalignment angles between a star's rotation axis and the orbital axis of its planets, is crucial for unraveling the mechanisms of planetary formation and migration. In this study, we present an analysis of Rossiter-McLaughlin (RM) observations of the warm Jupiter exoplanet WASP-106 b. The high-precision radial velocity measurements were made with HARPS and HARPS-N during the transit of this planet. We aim to constrain the orientation of the planet's orbit relative to its host star's rotation axis. The RM observations are analyzed using a code which models the RM anomaly together with the Keplerian orbit given several parameters in combination with a Markov chain Monte Carlo implementation. We measure the projected stellar obliquity in the WASP-106 system for the first time and find $\lambda = (-1 \pm 11)^\circ$, supporting the theory of quiescent migration through the disk.Comment: 12 pages, 3 figures, 4 tables, submitted to AA

The Ursinus Weekly, February 15, 1965

Lorelei at Sunnybrook features Lester Lanin: Ten Whitians named, John Wirth crowned king • Forum presents Hinderas performing American works • Inter-Fraternity Council plans three part weekend: To be first in series of Winter events • Agency presents British TW3 in conjunction with Greek weekend: London group here Thursday • Rights workers to speak on Miss. Summer project • Phi Beta Kappa professors seek student chapter • Y and Curtain Club cooperate on JB production • Campus Chest committee chooses groups to benefit • Editorial: Time for a change • Student teachers relate classroom experiences • Giovanni\u27s Room = Departure for Baldwin • Students help to convert gift shop into coffee house • Letters to the editor • Matmen take 3 out of 4; Lose to Elizabethtown • Snellbelles win first of season • Bears win 2 to snap streak; Stand 6-7 for season • First draft of course descriptions discovered • Greek gleaningshttps://digitalcommons.ursinus.edu/weekly/1239/thumbnail.jp

Constraining the reflective properties of WASP-178 b using CHEOPS photometry

Context. Multiwavelength photometry of the secondary eclipses of extrasolar planets is able to disentangle the reflected and thermally emitted light radiated from the planetary dayside. Based on this, we can measure the planetary geometric albedo Ag, which is an indicator of the presence of clouds in the atmosphere, and the recirculation efficiency ϵ, which quantifies the energy transport within the atmosphere. Aims. We measure Ag and ϵ for the planet WASP-178 b, a highly irradiated giant planet with an estimated equilibrium temperature of 2450 K. Methods. We analyzed archival spectra and the light curves collected by CHEOPS and TESS to characterize the host WASP-178, refine the ephemeris of the system, and measure the eclipse depth in the passbands of the two telescopes. Results. We measured a marginally significant eclipse depth of 70 ± 40 ppm in the TESS passband, and a statistically significant depth of 70 ± 20 ppm in the CHEOPS passband. Conclusions. Combining the eclipse-depth measurement in the CHEOPS (λeff = 6300 Å) and TESS (λeff = 8000 Å) passbands, we constrained the dayside brightness temperature of WASP-178 b in the 2250–2800 K interval. The geometric albedo 0.10.7 makes WASP-178 b an interesting laboratory for testing the current heat-recirculation models

Simultaneous observations of HD 106315 with 11 identical telescopes

The Next Generation Transit Survey (NGTS) is a photometric survey for transiting exoplanets, consisting of 12 identical 0.2‐m telescopes. We report a measurement of the transit of HD 106315 c using a novel observing mode in which multiple NGTS telescopes observed the same target, with the aim of increasing the signal‐to‐noise ratio. Combining the data allows the robust detection of the transit, which has a depth less than 0.1%, rivaling the performance of much larger telescopes. We demonstrate the capability of NGTS to contribute to the follow‐up of K2 and Transiting Exoplanet Survey Satellite discoveries using this observing mode. In particular, NGTS is well‐suited to the measurement of shallow transits of bright targets. This is particularly important to improve orbital ephemerides of relatively long‐period planets, where only a small number of transits are observed from space

Chemical combinations elucidate pathway interactions and regulation relevant to Hepatitis C replication

SREBP-2, oxidosqualene cyclase (OSC) or lanosterol demethylase were identified as novel sterol pathway-associated targets that, when probed with chemical agents, can inhibit hepatitis C virus (HCV) replication.Using a combination chemical genetics approach, combinations of chemicals targeting sterol pathway enzymes downstream of and including OSC or protein geranylgeranyl transferase I (PGGT) produce robust and selective synergistic inhibition of HCV replication. Inhibition of enzymes upstream of OSC elicit proviral responses that are dominant to the effects of inhibiting all downstream targets.Inhibition of the sterol pathway without inhibition of regulatory feedback mechanisms ultimately results in an increase in HCV replication because of a compensatory upregulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) expression. Increases in HMGCR expression without inhibition of HMGCR enzymatic activity ultimately stimulate HCV replication through increasing the cellular pool of geranylgeranyl pyrophosphate (GGPP).Chemical inhibitors that ultimately prevent SREBP-2 activation, inhibit PGGT or encourage the production of polar sterols have great potential as HCV therapeutics if associated toxicities can be reduced