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The 3D printing of pre-ceramic polymers that can be pyrolyzed into functional ceramics has recently become a focus for advanced ceramic applications requiring complex geometries. In this work, a new methodology for 3D printing SiCNO ceramic materials derived from a novel pre-ceramic photopolymer feedstock utilizing a thiol-ene reaction is introduced. The printed parts are pyrolyzed to amorphous SiCNO and the physical and mechanical properties of the final ceramic are measured. Pyrolysis of the pre-ceramic produced a SiCNO ceramic with 41% ceramic yield and shrinkage of 24% with a hardness measured at 6.6 GPa ± 0.3 GPa.

I investigate whether algorithmic trading (AT) affects the provision of management guidance. Existing research finds that AT decreases fundamental information acquisition before earnings announcements and consequently reduces the informativeness of prices. To compensate for reduced information acquisition, I predict and find that managers at firms with more AT activity increase the quantity and quality of guidance issued at earnings announcements. Evidence is consistent with managers responding to reduced information acquisition, as opposed to changes in liquidity, and results suggest guidance in response to AT is effective at reducing information asymmetry. These findings identify a new channel through which AT affects stock price informativeness by documenting a link to managers' disclosure decisions. Data Availability: Data are available from the public sources cited in the text. JEL Classifications: G14; G19; G10. [ABSTRACT FROM AUTHOR]

This paper reports a preliminary survey of one of humanity's most historic harbors--Alexandria, Egypt. It constitutes one phase of a broader joint land/sea examination of the largest and most famous city to bear Alexander the Great's name. The research overall had two goals: 1) to resolve locational uncertainties concerning the city's past configuration, particularly its Ptolemaic antecedents; and 2) to compare electronic remote sensing survey technologies with Remote Viewing generally, and the applications methodology developed by the Mobius Groups specifically. In the area of the Eastern Harbor, the aim of the research was: 1) the location of the ancient shore line; the locaton of and predictive description of several sites including the island of Antirrhodus and the Emporium/Poseidium/Timonium complex; a palace complex associated with Cleopatra; and a further elaboration, both in terms of location and predictive description, of the Pharos lighthouse area; 2) a comparison of Remote Viewing and side scan sonar data after each approach had surveyed the same area. This paper describes the probable location of the Emporium, the Poseidium, and the Timonium, the palace complex of Cleopatra, the island of Antirrhodus, a site at the tip of Fort Sisila (known prevously as Point Lochias), new discoveries pertaining to the lighthouse, andd an associated temple. The most important discovery though is the identification and location of the ancient seawall which extends some 65 meters farther out into the harbor than was previously suspected, and whoe location resolves a key piece in the puzzle of the ancient city's layout. The discoveries reported here were principally the result of Remote Viewing. Except for one clear "hit," side scan sonar proved unproductive because of the large amount of particulate in the water.

In the fall of 1987 Mobius began fieldwork, under a license from the Bahamian Government, to carry out an archaeological survey in an area of the Grand Bahama Banks encompassing some 579.15 square miles (1500 sq. km). This report compares the Remote Viewing, electronic remote sensing, and visual search process used to locate the wreck site of a previously undiscovered armed American merchantman believed to be the Brig Leander, which was found in a sub-section of the License Area known as Consensus Zone C; an area of 11.81 sq. miles (30.59 sq. km) of water. It concludes that Remote Viewing was the source of information which led to the site’s location, and that electronic remote sensing was not useful in this instance. Leander was under the Command of Captain William Johnson when she sank for unknown reasons near Beaks Cay on 6 April 1834, while returning from Manzanilla, Cuba to her homeport in Boston, Massachusetts. In addition to location information, a total of 193 conceptual descriptive concepts concerning the site were proffered by twelve Remote Viewers. Of this, 148 concepts, or 75% of the total, could be evaluated through direct field observations, or historical research. An evaluation of this material reveals 84% Correct, 12% Partially Correct, 4% Incorrect. There is little accuracy variation across the sequence of material from the Los Angeles interviews (84% Corr., 13% Part. Co rr. ,3% Incorr.), to the on-site data (81% Corr., 11% Part. Corr., 8% Incorr.). Approximately 300 notable wrecks went down, not just in the License Area but across the entire Banks, from 1500 to 1876 as determined by a thorough search of historical records and archival material in the U.S., the U.K., Spain and the Bahamas. To make a conservative assessment of this location occurring by chance, assume the wrecks are evenly distributed not throughout the Banks, but only within the License Area. That said, we should expect to see 6.12 boats in Consensus Zone C (11.81/579.15 x 300 =6.12). The brig site is 5000 square feet (464.5 sq. m), equaling 0.00018 of a square mile. Within Consensus Zone C 65,849 sites of this size could be placed, thus yielding a grid of 65,849 cells.. If the probability of selecting this particular cell in the grid by chance exceeds p≥ 0.05 then Remote Viewing can be considered a determinative factor. The probability of finding this one 5,000 square feet area is then 6.12/65,849 = p 0.00009, which strongly suggests that chance is not an explanation for the location of Leander. History: “The Discovery of an American Brig: Fieldwork Involving Applied Archaeological Remote Viewing,” Parapsychological Association Conference 1988. Also, The Discovery of an American Brig: Fieldwork Involving Applied Archaeological Remote Viewing, Including a Comparison with Electronic Remote Sensing,” Conference on Underwater Archaeology/Society of Historic Archaeology Annual Meetings. 1989.

As activity in Earth orbit continues to grow, it is important to characterize the environment of near‐Earth space. One means of remotely sensing lower thermospheric neutrals is by measurement of O and N2 density through the observation of far‐ultraviolet (FUV) airglow of atomic oxygen at 135.6 nm and the N2 Lyman‐Birge‐Hopfield (LBH) bands (~130–180 nm), as has been done on the Ionospheric Connection Explorer (ICON), Global‐scale Observations of the Limb and Disk (GOLD), and Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) missions. This technique is not without limitations, however, as the FUV measurements suffer from contamination by ionospheric emissions at low latitudes and auroral emissions excited by precipitating energetic electrons and protons at high latitudes. Previous work has shown the potential for making measurements of O and N2 density in the lower‐middle thermosphere using observations of extreme‐ultraviolet (EUV) airglow. This measurement approach has a potential advantage in that it does not have an inherent ionospheric emission that must be accounted for. Additionally, these emissions are primarily excited directly by solar UV rather than electron impact and thus have the potential to enable expansion of neutral density observations into the auroral zone and polar cap where the FUV measurement cannot be applied. This article demonstrates a new approach and algorithm designed to retrieve thermospheric O and N2 density from 150 to 400 km using measurements from the ICON EUV instrument. The retrieval results throughout 2020 are summarized and compared to measurements from ICON FUV, GOLD, and SWARM. Plain Language Summary: The region of space where most satellites orbit is almost empty ‐ but not completely empty. The small amount of nitrogen and oxygen gas present can cause satellites to gradually fall out of orbit through drag. A failure to understand and evaluate changes in the density of the upper atmosphere led to the loss of 38 Starlink satellites in February 2022, for example, This is one reason that it is important to understand how much gas is in near‐Earth space and how the amount changes over time, but orbit decay due to drag makes it difficult to make direct measurements. One common solution is to measure the amount of gas from afar, taking advantage of the fact that these gases emit small amounts of light in the far‐UV spectrum. There are some limitations to this approach, one of which being that charged particles in the same region can create an extra and unrelated signal, which requires correction. This paper presents a novel approach which uses more energetic extreme‐UV light as an alternative to the far‐UV. We show the results of this new algorithm and demonstrate that the measurements line up well with those from other instruments and spacecraft. Key Points: We present an algorithm concept for remote sensing thermospheric O and N2, novel in its use of EUV airglow measurementsComparison to related measurements during conjunctions with ICON FUV, GOLD, and Swarm are favorableRetrieval results from 2020 indicate cooler atmospheres than those predicted by MSIS [ABSTRACT FROM AUTHOR]

This paper reports the location and reconstruction of a Byzantine structure in the now buried city of Marea along the shores of Lake Maryut, some 44 km southwest of Alexandria, Egypt. A Pharonic trade center that was occupied until the 16th Century, the city has been long abandoned and lies buried around what formerly was the lakeshore. This paper reports on an applied Remote Viewing experiment in which two Remote Viewers were asked to first locate Marea, and then a buried building within the city and, finally, to describe what would be found within the building site selected, with a particularly emphasis on tile and other decorative material. It also includes a comparison of Remote Viewing data with electronic remote sensing, and geographical data for the same area done independently three years earlier. The comparison is striking because while the Remote Viewers were successfully able to locate a building, including staking out its door, and corners, as well as providing a wealth of reconstructive and descriptive material about what would be found at the site, the electronic remote sensing and geographical analysis produced no suggestion whatever that there was a site at this location. For this reason, prior to discovery, much of the Remote Viewing data seemed extremely improbable, and notably contradicted the informed judgment of an archaeologist deemed by the University of Alexandria to be the leading authority on Marea. History: The Marea Probe: An Experiment in Applied Parapsychology involving the Location, Reconstruction, and Excavation of a Byzantine Structure - Marea, Egypt. Invited Paper. Annual Meetings of The American Research Center in Egypt. De Young Museum. 14 April 1980. Also presented at the annual meetings of the Parapsychology Association 1980. Proceedings of the Parapsychology Association – 1980.

The UK’s Defence Science and Technology Laboratory (Dstl) is partnering with the US Naval Research Laboratory (NRL) on a joint mission to launch miniature sensors that will advance space weather measurement and modelling capabilities. The Coordinated Ionospheric Reconstruction Cubesat Experiment (CIRCE) comprises two 6U cube-satellites that will be launched into a near-polar low earth orbit (LEO), targeting 500 km altitude, in 2021. The UK contribution to CIRCE is the In situ and Remote Ionospheric Sensing (IRIS) suite, complementary to NRL sensors, and comprising three highly miniaturised payloads provided to Dstl by University College London (UCL), University of Bath, and University of Surrey/Surrey Satellite Technology Ltd (SSTL). One IRIS suite will be flown on each satellite, and incorporates an ion/neutral mass spectrometer, a tri-band global positioning system (GPS) receiver for ionospheric remote sensing, and a radiation environment monitor. From the US, NRL have provided two 1U Triple Tiny Ionospheric Photometers (Tri-TIPs) on each satellite (Nicholas et al., 2019), observing the ultraviolet 135.6 nm emission of atomic oxygen at night-time to characterize the two-dimensional distribution of electrons.

The ionospheric O+ number density can be measured remotely during the day by observing its optically thick 83.4 nm radiance. Some ambiguity is present in the process of retrieving the density due to uncertainties in the initial excitation rate. This can be removed by observing a companion optically thin emission at 61.7 nm originating from the O+(3s 2P) state, providing that the ratio of the initial excitation rates is known. Analyses of ICON EUV data using an 83.4/61.7 emission ratio of order 10 result in O+ densities lower by ∼2 than other measurements. Key to relating the two emissions is accurate knowledge of the partial photoionization cross sections and the spectroscopy of O+—the topic of this paper. Up to now, no independent evaluation of the ratio of the 83.4/61.6 emission ratio exists. The recent availability of state‐of‐the‐art calculations of O partial photoionization cross sections into a variety of O+ states presents an opportunity to evaluate the O+(2p44P)/O+(3s 2P) ionization rate ratio. We calculate excitation of these parent states of the emissions including both direct and cascade excitation from higher lying O+ energy states. The resulting theoretical prediction gives ratios that range from 13.5 to 12 from solar minimum to maximum, larger than the value of 10 used by the ICON 83.4 and 61.7 nm algorithm. The higher theoretical values for the ratio reconcile the ∼2 discrepancy between simultaneous ICON and other electron density measurements. Key Points: OII 83.4 and 61.7 nm emission rates are being used for remote sensing of O+ in the daytime ionosphereNew O partial photoionization cross sections predict higher than currently used values for the 83.4/61.7 nm volume emission rate ratioThe higher theoretical values of the 83.4/61.7 nm ratio reconcile discrepancies between ICON and other simultaneous observations [ABSTRACT FROM AUTHOR]

We provide initial evidence that stock exchange procedures around closing auctions advantage speed traders at the expense of auction participants. We show that, on Nasdaq and NYSE Arca, 4:00 pm earnings releases result in informed trading in the continuous regular-hour session in the short window between 4:00 pm and the closing auction; this trading subsequently moves closing prices in the direction of the earnings news. The ability of speed traders to submit 4:00-pm-news orders to the auction through the continuous session earns them up to 1.5 percent profit and creates an unlevel playing field because most auction participants are not allowed to cancel their orders. When stock exchanges recommended that firms delay disclosures until after the market closes, those with higher institutional ownership were more likely to voluntarily do so. Our study has implications regarding the timing of information releases and the design of the closing process. [ABSTRACT FROM AUTHOR]

Since the earliest space‐based observations of Earth's atmosphere, ultraviolet (UV) airglow has proven a useful resource for remote sensing of the ionosphere and thermosphere. The NASA Ionospheric Connection Explorer (ICON) spacecraft, whose mission is to explore the connections between ionosphere and thermosphere utilizes UV airglow in the typical way: an extreme‐UV (EUV) spectrometer uses dayglow between 54 and 88 nm to measure the density of O+, and a far‐UV spectrograph uses the O 135.6 nm doublet and N2 Lyman‐Birge‐Hopfield band dayglow to measure the column ratio of O to N2 in the upper thermosphere. Two EUV emission features, O+ 61.6 and 83.4 nm, are used for the O+ retrieval; however, many other features are captured along the EUV instrument's spectral dimension. In this study, we examine the other dayglow features observed by ICON EUV and demonstrate that it measures a nitrogen feature around 87.8 nm which can be used to observe the neutral thermosphere. Plain Language Summary: The ionosphere is a region of near‐Earth space made up of plasma. NASA's Ionospheric Connection Explorer (ICON) mission seeks explore the factors influencing formation of the ionosphere and how it interacts with Earth and its atmosphere. One of the ways ICON does this is by measuring airglow: light released by the air in the upper atmosphere. This occurs with visible light, with the same shades seen in the aurora; it also occurs in the ultraviolet range, invisible to the human eye but visible to ICON instruments. An imager is included on ICON to measure extreme‐ultraviolet light, almost as energetic as X‐rays. Certain atoms and molecules in the atmosphere are known to glow at specific wavelengths. By measuring the brightness of airglow at certain wavelengths, ICON is able see the structure of ionospheric oxygen. The instrument also measures dimmer emissions at other wavelengths, some of which are known to come from certain atmospheric species and others which are unknown or uncertain. Here we look at the other wavelengths and attempt to find their origins. We find that most are likely coming from oxygen. Interestingly, we find one that we think comes from nitrogen. This could be useful for measuring the abundance of molecular nitrogen in the upper atmosphere, a task currently performed by another instrument on the ICON spacecraft. We make a case for the practicality of this approach. Key Points: A comprehensive introduction to the Ionospheric Connection Explorer Extreme ultraviolet dayglow observations is presentedSome dim emission features are identified as originating from O+ from similarity to known featuresEmission near 87.8 nm follows N2 and, combined with 61.6 nm data, contains information about ΣO/N2 [ABSTRACT FROM AUTHOR]

A bright neutron source such as the spallation neutron source (SNS) places extreme requirements on detectors including excellent 2-D spatial imaging and high dynamic range. Present imaging detectors have either shown position resolutions that are less than acceptable or they exhibit excessive paralyzing dead times due to the brightness of the source. A detector concept known as MicroMegas (MicroMEsh GAseous Structure) has been developed at CERN, Geneva, Switzerland, for high-energy physics charged-particle tracking applications and has shown great promise for handling high data rates with a rather low-cost structure. We are attempting to optimize the MicroMegas detector concept for thermal neutrons and have designed a 1-D neutron strip detector utilizing solid converters which we have tested. In addition, we are performing research into the compatibility of various converter coatings. Our goal is to develop a manufacturable detector that could be scaled to a 1 [m.sup.2], 2-D array for use at the SNS and other facilities. Index Terms--Neutrons, radiation detector.

In near‐Earth space, variations in thermospheric composition have important implications for thermosphere‐ionosphere coupling. The ratio of O to N2 is often measured using far‐UV airglow observations. Taking such airglow observations from space, looking below the Earth's limb allows for the total column of O and N2 in the ionosphere to be determined. While these observations have enabled many previous studies, determining the impact of nonmigrating tides on thermospheric composition has proved difficult, owing to a small contamination of the signal by recombination of ionospheric O+. New ICON observations of far‐UV are presented here, and their general characteristics are shown. Using these, along with other observations and a global circulation model, we show that during the morning hours and at latitudes away from the peak of the equatorial ionospheric anomaly, the impact of nonmigrating tides on thermospheric composition can be observed. During March–April 2020, the column O/N2 ratio was seen to vary by 3–4% of the zonal mean. By comparing the amplitude of the variation observed with that in the model, both the utility of these observations and a pathway to enable future studies is shown. Plain Language Summary: At high altitude in the atmosphere, mixing of the gas via turbulence becomes less important, and mix of atmospheric species begins to vary with altitude, depending on the mass of the atom or molecule. At these altitudes, the composition of the atmosphere can vary greatly with location and time in a manner not seen in the lower levels of the atmosphere. This same high‐altitude region overlaps with the charged particle environment known as the Earth's ionosphere. How the atmosphere and ionosphere interact is in‐part determined by the composition of the atmosphere. Measuring this composition is therefore important and is done regularly using observations in the far‐ultraviolet. These reveal much of the compositional variation, but a small contaminating signal from the ionosphere has made detecting some small changes produced by waves in the atmosphere a challenge. Here, new observations in the far‐UV are introduced and their general properties shown. By selecting a specific location and time and utilizing supporting data and a global model, we are able to show the change in the composition produced by a certain class of wave in the atmosphere. This demonstrates the utility of these new observations and provides a pathway to futures studies. Key Points: An initial overview of the Ionospheric Connection Explorer‐far‐ultraviolet sublimb observations and derived column O/N2 ratios is presentedIn the morning, away from the equatorial ionosphere, the impact of nonmigrating tides on O/N2 is shown clearly for the first timeComparison of the tidal signature with the TIEGCM highlights basic agreement, with possible discrepancy in tidal vertical wavelength [ABSTRACT FROM AUTHOR]

The NASA Ionospheric Connection Explorer Far-Ultraviolet spectrometer, ICON FUV, will measure altitude profiles of the daytime far-ultraviolet (FUV) OI 135.6 nm and N2 Lyman-Birge-Hopfield (LBH) band emissions that are used to determine thermospheric density profiles and state parameters related to thermospheric composition; specifically the thermospheric column O/N2 ratio (symbolized as Σ O/N2). This paper describes the algorithm concept that has been adapted and updated from one previously applied with success to limb data from the Global Ultraviolet Imager (GUVI) on the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission. We also describe the requirements that are imposed on the ICON FUV to measure Σ O/N2 over any 500-km sample in daytime with a precision of better than 8.7%. We present results from orbit-simulation testing that demonstrates that the ICON FUV and our thermospheric composition retrieval algorithm can meet these requirements and provide the measurements necessary to address ICON science objectives. [ABSTRACT FROM AUTHOR]