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  1. Abstract Efforts to promote responsible conduct of research (RCR) should take into consideration how scientists already conceptualize the relationship between ethics and science. In this study, we investigated how scientists relate ethics and science by analyzing the values expressed in interviews with fifteen science faculty members at a large midwestern university. We identified the values the scientists appealed to when discussing research ethics, how explicitly they related their values to ethics, and the relationships between the values they appealed to. We found that the scientists in our study appealed to epistemic and ethical values with about the same frequency, and much more often than any other type of value. We also found that they explicitly associated epistemic values with ethical values. Participants were more likely to describe epistemic and ethical values as supporting each other, rather than trading off with each other. This suggests that many scientists already have a sophisticated understanding of the relationship between ethics and science, which may be an important resource for RCR training interventions.
    Free, publicly-accessible full text available June 1, 2024

    Small Solar system bodies have widely dispersed orbital poles, posing challenges to dynamical models of Solar system origin and evolution. To characterize the orbit pole distribution of dynamical groups of small bodies it helps to have a functional form for a model of the distribution function. Previous studies have used the small-inclination approximation and adopted variations of the normal distribution to model orbital inclination dispersions. Because the orbital pole is a directional variable, its distribution can be more appropriately modelled with directional statistics. We describe the von Mises–Fisher (vMF) distribution on the surface of the unit sphere for application to small bodies’ orbital poles. We apply it to the orbit pole distribution of the observed Plutinos. We find a mean pole located at inclination i0 = 3.57° and longitude of ascending node Ω0 = 124.38° (in the J2000 reference frame), with a 99.7 per cent confidence cone of half-angle 1.68°. We also estimate a debiased mean pole located 4.6° away, at i0 = 2.26°, Ω0 = 292.69°, of similar-size confidence cone. The vMF concentration parameter of Plutino inclinations (relative to either mean pole estimate) is κ = 31.6. This resembles a Rayleigh distribution function, with width parameter σ = 10.2°. Unlike previous models, the vMF model naturallymore »accommodates all physical inclinations (and no others), whereas Rayleigh or Gaussian models must be truncated to the physical inclination range 0–180°. Further work is needed to produce a theory for the mean pole of the Plutinos against which to compare the observational results.

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  3. Abstract. Rapid warming of the Arctic terrestrial region has the potential to increase soil decomposition rates and form a carbon-driven feedback to future climate change. For an accurate prediction of the role of soil microbes in these processes, it will be important to understand the temperature responses of soil bacterial communities and implement them into biogeochemical models. The temperature adaptation of soil bacterial communities for a large part of the Arctic region is unknown. We evaluated the current temperature adaption of soil bacterial communities from 12 sampling sites in the sub- to High Arctic region. Temperature adaptation differed substantially between the soil bacterial communities of these sites, with estimates of optimal growth temperature (Topt) ranging between 23.4 ± 0.5 and 34.1 ± 3.7 ∘C. We evaluated possible statistical models for the prediction of the temperature adaption of soil bacterial communities based on different climate indices derived from soil temperature records or on bacterial community composition data. We found that highest daily average soil temperature was the best predictor for the Topt of the soil bacterial communities, increasing by 0.63 ∘C ∘C−1. We found no support for the prediction of temperature adaptation by regression tree analysis based on the relative abundance data of the most common bacterial species.more »Increasing summer temperatures will likely increase Topt of soil bacterial communities in the Arctic. Incorporating this mechanism into soil biogeochemical models and combining it with projections of soil temperature will help to reduce uncertainty in assessments of the vulnerability of soil carbon stocks in the Arctic.« less
    Free, publicly-accessible full text available January 1, 2024
  4. Free, publicly-accessible full text available December 5, 2023
  5. Free, publicly-accessible full text available January 1, 2024
  6. Surveys of Hawaiian macroalgae over the past 15 years have yielded numerous specimens representing species new to science. Calliblepharis yasutakei sp. nov. is here described based on a plant collected at a depth of 98 m from Kapou, Papahânaumokuâkea Marine National Monument, Hawaiʻi. Phylogenetic analyses of three molecular markers (COI, rbcL, and SSU) and analyses of morphological features were used to describe the new species in the family Cystocloniaceae. Calliblepharis yasutakei sp. nov. grouped with C. fimbriata, C. rammediorum, C. occidentalis and C. jolyi in a clade with full support for the rbcL analysis, representing a distinct lineage within the genus. Phylogenetic and vegetative morphological comparisons demonstrated that the new Hawaiian species is most closely related to C. rammediorum from Israel (rbcL similarity of 96.3%), although no female reproductive structures were found to allow a more comprehensive comparison. In order to determine whether C. yasutakei represents the first confirmed report of the genus Calliblepharis in the Hawaiian Islands, phylogenetic and morphological analysis of the Hawaiian Hypnea saidana (=Calliblepharis saidana) specimen accessioned at the Bernice P. Bishop Museum was performed. These analyses demonstrated that this specimen belongs to a new species in the genus Hypnea, which is here described as H.more »tsudae sp. nov. C. yasutakei, in addition to being a new species, is also reported as the first confirmed record of the genus Calliblepharis in the Hawaiian archipelago, and the description of H. tsudae brings the number of species for this genus in Hawaiʻi to eight.« less
    Free, publicly-accessible full text available November 8, 2023
  7. Abstract Changing wildfire regimes in the western US and other fire-prone regions pose considerable risks to human health and ecosystem function. However, our understanding of wildfire behavior is still limited by a lack of data products that systematically quantify fire spread, behavior and impacts. Here we develop a novel object-based system for tracking the progression of individual fires using 375 m Visible Infrared Imaging Radiometer Suite active fire detections. At each half-daily time step, fire pixels are clustered according to their spatial proximity, and are either appended to an existing active fire object or are assigned to a new object. This automatic system allows us to update the attributes of each fire event, delineate the fire perimeter, and identify the active fire front shortly after satellite data acquisition. Using this system, we mapped the history of California fires during 2012–2020. Our approach and data stream may be useful for calibration and evaluation of fire spread models, estimation of near-real-time wildfire emissions, and as means for prescribing initial conditions in fire forecast models.
    Free, publicly-accessible full text available December 1, 2023
  8. Frank, Brian ; Jones, Dyan ; Ryan, Qing (Ed.)
    Researchers across all scientific disciplines routinely face ethical decisions in their work, from addressing conflicts of interest to deciding whether and how to make data available for reproducibility. To help strengthen their ethical reasoning skills, they are encouraged to take online training programs like the CITI program. Ethics training is insufficient for improving ethical behavior. Better understanding of how scientists make decisions and reason about ethics is needed. To develop that understanding, we need expanded, asset-based measures of ethical reasoning that can be applied to open-ended responses and discussions. As part of a year-long intervention on a group of fifteen scientists' value-based reasoning, we conducted pre/post interviews that included open-ended questions about ethical scenarios. For this paper, we explore an application of three theories of ethical and stakeholder reasoning to those answers, and determine that we can use them to examine quality, principles, and subjects of their reasoning in open responses.
    Free, publicly-accessible full text available September 22, 2023
  9. Two genera of the Rhodymeniales, Halopeltis and Leptofauchea, are here reported for the first time from the Hawaiian Islands and represent the deepest records for both genera. Molecular phylogenetic analyses of cytochrome oxidase subunit I (COI), rbcL, and large subunit ribosomal DNA (LSU) sequences for Hawaiian specimens of Leptofauchea revealed one well-supported clade of Hawaiian specimens and three additional lineages. One of these clades is described here as Leptofauchea huawelau sp. nov., and is thus far known only from mesophotic depths at Penguin Bank in the Main Hawaiian Islands. L. huawelau sp. nov. is up to 21 cm, and is the largest known species. An additional lineage identified in the LSU and rbcL analyses corresponds to the recently described L. lucida from Western Australia, and is a new record for Hawai‘i. Hawaiian Halopeltis formed a well-supported clade along with H. adnata from Korea, the recently described H. tanakae from mesophotic depths in Japan, and H. willisii from North Carolina, and is here described as Halopeltis nuahilihilia sp. nov. H. nuahilihilia sp. nov. has a distinctive morphology of narrow vegetative axes that harbor constrictions along their length. The current distribution of H. nuahilihilia includes mesophotic depths around W. Maui, W. Moloka‘i,more »and the island of Hawai‘i in the Main Hawaiian Islands. Few reproductive characters were observed because of the small number of specimens available; however, both species are distinct based on phylogeny and morphology. These descriptions further emphasize the Hawaiian mesophotic zone as a location harboring many undescribed species of marine macroalgae.« less
    Free, publicly-accessible full text available December 1, 2023
  10. Free, publicly-accessible full text available September 3, 2023