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INTRODUCTION: Physicians look to various electronic resources to aid in management of patient treatment. While national guidelines encourage clinical trial participation for cancer patients, it is unclear if physician facing resources help guide physicians to appropriate trials in which to enroll their patients. If resources do not mention appropriate open clinical trials, physicians miss a major management strategy. METHODS: A list of open breast cancer trials as of June 15, 2020 was obtained from the National Clinical Trial Network (NCTN). Physician facing electronic resources including UpToDate, DynaMed, WebMD, Medscape, theMedNet, WebMD, and ClinicalKey, were queried for each trial. The long name of the trial, trial name, any abbreviation associated with the trial, and definitive type of breast cancer characteristics qualifying for the trial were searched for in the database. Relevant management topics within each resource were also reviewed for mention of any open trial. A spreadsheet was constructed and trial mentions were tabulated. RESULTS: The 17 trials were found mentioned 19 times across all 6 resources resulting in clinical trials being mentioned an average of 18%, with a range of 6%-47%. A total of 47% of open NCTN breast trials were mentioned on the MedNet, the highest rate of any platform. Trials were mentioned the least on DynaMed and ClinicalKey at a rate of 6%. Clinical trial mentions did not always correlate with recommendation of enrollment or promotion of participation in the trial. The majority of mentions were found by searching the specific trial name. CONCLUSION: Participation in clinical trials is almost always advised for breast cancer patients. However, access to open trial information is minimal within physician-facing electronic resources. Information on open or appropriate clinical trials rarely accompanies the recommendation for research participation. With extensive probing of physician facing databases, open clinical trials were mentioned only 18% of the time (range of 6%-47%). The lack of exposure of open clinical trials in physician facing electronic databases increases the difficulty of adherence to the recommendation of clinical trial enrollment as a management strategy. In addition to missing a major management strategy, the lack of representation of the trials may be a barrier to appropriate referrals. Mentions of Trials within Physician Facing Electronic ResourcesTrialUp to DateDynaMedWebMDMedScapeMedNetClinicalKeyEA1181NoNoNoNoNoNoNRG-BR005NoNoYesYesNoNoS1706NoNoNoNoNoNoNSABP B-51YesNoNoNoYesNoA011202NoNoNoNoYesNoEA1131NoNoNoNoYesNoS1418NoNoNoNoYesNoNRG- BR003NoNoYesNoYesNoCCTG MA.39NoNoNoNoYesNoA011401 (BWEL)NoNoNoNoYesNoA011502 (ABC)YesNoNoNoNoYesEAI142NoNoNoNoNoNoNRG- BR002NoNoYesNoYesNoEA1183 (FEATURE)NoNoNoNoNoNoNRG- BR004NoNoNoNoNoNoEAY131 (MATCH)YesNoNoYesNoNoS1609 (DART)YesYesNoNoNoNoPercent mentioned24%6%18%12%47%6% Citation Format: Elizabeth Carey, Amarinthia Curtis. National Clinical Trial Network Breast Trial mentions in electronic physician resources [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-33.

Measuring the physical properties of geological materials is important for understanding geologic history. Yet there has never been an instrument with the purpose of measuring mechanical properties of rocks sent to another planet. The Mars Science Laboratory (MSL) rover employs the Powder Acquisition Drill System (PADS), which provides direct mechanical interaction with Martian outcrops. While the objective of the drill system is not to make scientific measurements, the drill's performance is directly influenced by the mechanical properties of the rocks it drills into. We have developed a methodology that uses the drill to indicate the uniaxial compressive strengths of rocks through comparison with performance of an identically assembled drill system in terrestrial samples of comparable sedimentary class. During this investigation, we utilize engineering data collected on Mars to calculate the percussive energy needed to maintain a prescribed rate of penetration and correlate that to rock strength.

Comets are icy remnants of the Solar System formation, and as such contain some of the most primitive volatiles and organic materials. Sampling the surface of a comet is a high priority for the New Frontiers program. Planetary simulants are crucial to the development of adequate in situ instruments and sample acquisition systems. A high-fidelity comet surface simulant has been developed to support hardware design and development for one Comet Surface Sample Return tool, the BiBlade Comet Sampler. Mechanical Porous Ambient Comet Simulants (MPACS) can be manufactured to cover a wide range of desired physical properties, such as density and cone penetration resistance, and exhibit a brittle fracture mode. The structure of the MPACS materials is an aggregated composite structure of weakly-bonded grains of very small size (diameter ≤ 40 μm) that are most relevant to the structure of the surface of a comet nucleus.

© 2014 Elsevier B.V. Vesta, the second most massive asteroid, has long been perceived as anhydrous. Recent studies suggesting the presence of hydrated minerals and past subsurface water have challenged this long-standing perception. Yet, direct geologic indications of water activity on Vesta's surface were unexpected. Herein we show evidence that transient water flowed on the surface, in a debris-flow-like process, and left distinctive geomorphologic features. Based on detailed analysis of highest-resolution (~20 m/pixel) images obtained by the Dawn spacecraft, we identify a class of locally occurring, interconnected and curvilinear gully networks on the walls of young (< hundreds of Ma) impact craters, ending in lobate deposits near the crater floors. As curvilinear systems only occur within impact craters, we propose that they formed by a particulate-dominated flow of transient water that was released from buried ice-bearing deposits by impact-induced heating and melting. This interpretation is in accordance with the occurrence of pitted terrain on lobate deposits and crater floors. Pitted terrain is proposed to result from the degassing of volatiles. The proposed buried ice-bearing deposits are likely localized in extent and may be currently extant in Vesta's subsurface. Together with the discovery of water evaporation on Ceres and water activity on several small asteroids, our results support the new paradigm that water is widespread in the asteroid belt.

The BiBlade sampling chain was developed for use in a potential Comet Surface Sample Return mission. Following prior versions of the sampling tool, a new tool was developed and validated to TRL 6. Sample acquisition testing was performed across a range of comet simulants and operational conditions. Tool operation was validated in a thermal-vacuum chamber. The end-to-end sampling chain was validated including sampling, sample measurement, and sample transfer. The sampling system is now ready for flight implementation.

The BiBlade sampling chain has been developed for use in a potential Comet Surface Sample Return mission in a touch-and-go mission architecture. This paper describes the BiBlade sampling chain, an implementation of the system and experimental results. The system includes a BiBlade sampling tool, a robotic arm, a sample measurement system, a sample transfer system, and simulants.

The planetary science decadal survey for 2013-2022 (Vision and Voyages, NRC 2011) has promoted mission concepts for sample acquisition from small solar system bodies. Numerous comet-sampling tools are in development to meet this standard. Manufactured Porous Ambient Surface Simulants (MPASS) materials provide an opportunity to simulate variable features at ambient temperatures and pressures to appropriately test potential sample acquisition systems for comets, asteroids, and planetary surfaces. The original "flavor" of MPASS materials is known as Manufactured Porous Ambient Comet Simulants (MPACS), which was developed in parallel with the development of the Biblade Comet Sampling System (Backes et al., in review). The current suite of MPACS materials was developed through research of the physical and mechanical properties of comets from past comet missions results and modeling efforts, coordination with the science community at the Jet Propulsion Laboratory and testing of a wide range of materials and formulations. These simulants were required to represent the physical and mechanical properties of cometary nuclei, based on the current understanding of the science community. Working with cryogenic simulants can be tedious and costly; thus MPACS is a suite of ambient simulants that yields a brittle failure mode similar to that of cryogenic icy materials. Here we describe our suite of comet simulants known as MPACS that will be used to test and validate the Biblade Comet Sampling System (Backes et al., in review).

In a series of laboratory experiments, we measure thermal diffusivity, thermal conductivity, and heat capacity of icy regolith created by vapor deposition of water below its triple point and in a low pressure atmosphere. We find that an ice-regolith mixture prepared in this manner, which may be common on Mars, and potentially also present on the Moon, Mercury, comets and other bodies, has a thermal conductivity that increases approximately linearly with ice content. This trend differs substantially from thermal property models based of preferential formation of ice at grain contacts previously applied to both terrestrial and non-terrestrial subsurface ice. We describe the observed microphysical structure of ice responsible for these thermal properties, which displaces interstitial gases, traps bubbles, exhibits anisotropic growth, and bridges non-neighboring grains. We also consider the applicability of these measurements to subsurface ice on Mars and other solar system bodies.

The biosynthesis of fatty acids has been studied in lactating rabbits at 6h after intravenous injection of sodium [1-14C]acetate. The specific radioactivities of the individual fatty acids (C6:0 to C14:0) and the proportions of these fatty acids synthesized were similar in mammary tissue and milk. Hexanoic acid had the highest specific radioactivity, and the C8:0–C14:0 fatty acids had similar specific radioactivities, which were about five times those of C16 and C18 acids. No radioactivity was detected in fatty acids of chain length C14 in these tissues were similar to those of the long-chain fatty acids in the milk and mammary gland. The results show that the C4:0–C14:0 fatty acids are synthesized within the mammary gland rather than by fatty acid uptake from circulating blood or by oxidation of long-chain fatty acids within the gland. We conclude that de novo synthesis of esterified fatty acids in vivo by this tissue has a high degree of chain-length specificity.