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abridged. Eclipsing binary systems provide the opportunity to measure the fundamental parameters of their component stars in a stellar-model-independent way. This makes them ideal candidates for testing and calibrating theories of stellar structure and (tidal) evolution. Even without spectroscopic follow-up there is often enough information in their photometric time series to warrant analysis, especially if there is an added value present in the form of intrinsic variability, such as pulsations. Our goal is to implement and validate a framework for the homogeneous analysis of large numbers of eclipsing binary light curves, such as the numerous high-duty-cycle observations from space missions like TESS. The aim of this framework is to be quick and simple to run and to limit the user's time investment when obtaining, amongst other parameters, orbital eccentricities. We developed a new and fully automated methodology for the analysis of eclipsing binary light curves with or without additional intrinsic variability. Our method includes a fast iterative pre-whitening procedure. Orbital and stellar parameters are measured under the assumption of spherical stars of uniform brightness. We tested our methodology in two settings: a set of synthetic light curves with known input and the catalogue of Kepler eclipsing binaries. The synthetic tests show that we can reliably recover the frequencies and amplitudes of the sinusoids included in the signal as well as the input binary parameters. Recovery of the tangential component of eccentricity is the most accurate and precise. Kepler results confirm a robust determination of orbital periods, with 80.5% of periods matching the catalogued ones. We present the eccentricities for this analysis and show that they broadly follow the theoretically expected pattern as a function of the orbital period., Comment: 17 pages, 17 figures, 1 table, 5 appendices (43 additional figures, 1 additional table). Accepted for publication in A&A

In the context of global climate change, ocean iron fertilization (OIF) has been suggested as a potential geoengineering strategy to enhance the growth of marine phytoplankton, subsequently promote the ocean carbon sink, and ultimately regulate atmospheric carbon dioxide (CO2) and mitigate climate change. However, in past artificial OIF experiments, the elevation of both net primary production and carbon export to the deep ocean is far less than anticipated. This discrepancy can be attributed to several key factors that strongly influence the efficiency of OIF and biological carbon pump (BCP) including iron bioavailability and retention time, the sensitivity of phytoplankton to iron limitation, the influence of viruses and other microorganisms comprising the microbial carbon pump (MCP), and non-biological carbon cycles. Although previous reviews have extensively summarized the outcomes of the past OIF experiments, the mechanisms and key factors that influence climate regulation mediated by OIF have not been elucidated. In this review, we analyze these mechanisms throughout the whole process from OIF, to phytoplankton physiological responses, to carbon dioxide removal (CDR) and sequestration in the ocean, and ultimately to CDR in the atmosphere and its impact on climate change. By examining both natural and artificial OIF cases, as well as recent advancements in phytoplankton physiological ecology and carbon pump theory, possible reasons leading to the inconsistencies between OIF and carbon export are explored. These comprehensive analyses are helpful to identify the key issues in regulating climate change by providing a reference and scientific approach to guide potential OIF attempts in the future. © 2023

An unprecedented devastating forest fire occurred in Australia from September 2019 to March 2020. Satellite observations revealed that this rare fire event in Australia destroyed a record amount of more than 202,387 km2 of forest, including 56,471 km2 in eastern Australia, which is mostly composed of evergreen forest. The released aerosols contained essential nutrients for the growth of marine phytoplankton and were transported by westerly winds over the Southern Ocean, with rainfall-induced deposition to the ocean beneath. Here, we show that a prominent oceanic bloom, indicated by the rapid growth of phytoplankton, took place in the Southern Ocean along the trajectory of fire-born aerosols in response to atmospheric deposition. Calculations of carbon released during the fire versus carbon absorbed by the oceanic phytoplankton bloom suggest that they were nearly equal. This finding illustrates the critical role of the oceans in mitigating natural and anthropogenic carbon dioxide releases to the atmosphere, which are a primary driver of climate change. © 2021 The Authors

An unprecedented devastating forest fire occurred in Australia from September 2019 to March 2020. Satellite observations revealed that this rare fire event in Australia destroyed a record amount of more than 202,387 km2 of forest, including 56,471 km2 in eastern Australia, which is mostly composed of evergreen forest. The released aerosols contained essential nutrients for the growth of marine phytoplankton and were transported by westerly winds over the Southern Ocean, with rainfall-induced deposition to the ocean beneath. Here, we show that a prominent oceanic bloom, indicated by the rapid growth of phytoplankton, took place in the Southern Ocean along the trajectory of fire-born aerosols in response to atmospheric deposition. Calculations of carbon released during the fire versus carbon absorbed by the oceanic phytoplankton bloom suggest that they were nearly equal. This finding illustrates the critical role of the oceans in mitigating natural and anthropogenic carbon dioxide releases to the atmosphere, which are a primary driver of climate change. © 2021 The Authors

Dataset: Coastal Maine CTD Data, This dataset includes vessel CTD profiles from the outer reaches of the Damariscotta River Estuary in the mid-coast region of Maine collected from June 2017 to July 2018. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/809309, NSF Division of Ocean Sciences (NSF OCE) OCE-1435021

Dataset: Coastal Maine CTD Data, This dataset includes vessel CTD profiles from the outer reaches of the Damariscotta River Estuary in the mid-coast region of Maine collected from June 2017 to July 2018. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/809309, NSF Division of Ocean Sciences (NSF OCE) OCE-1435021

Dataset: Coastal Maine CTD Data, This dataset includes vessel CTD profiles from the outer reaches of the Damariscotta River Estuary in the mid-coast region of Maine collected from June 2017 to July 2018. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/809309, NSF Division of Ocean Sciences (NSF OCE) OCE-1435021

Embedding ethics modules within computer science courses has become a popular response to the growing recognition that CS programs need to better equip their students to navigate the ethical dimensions of computing technologies like AI, machine learning, and big data analytics. However, the popularity of this approach has outpaced the evidence of its positive outcomes. To help close that gap, this empirical study reports positive results from Northeastern's program that embeds values analysis modules into CS courses. The resulting data suggest that such modules have a positive effect on students' moral attitudes and that students leave the modules believing they are more prepared to navigate the ethical dimensions they will likely face in their eventual careers. Importantly, these gains were accomplished at an institution without a philosophy doctoral program, suggesting this strategy can be effectively employed by a wider range of institutions than many have thought.

An unprecedented devastating forest fire occurred in Australia from September 2019 to March 2020. Satellite observations revealed that this rare fire event in Australia destroyed a record amount of more than 202,387 km2 of forest, including 56,471 km2 in eastern Australia, which is mostly composed of evergreen forest. The released aerosols contained essential nutrients for the growth of marine phytoplankton and were transported by westerly winds over the Southern Ocean, with rainfall-induced deposition to the ocean beneath. Here, we show that a prominent oceanic bloom, indicated by the rapid growth of phytoplankton, took place in the Southern Ocean along the trajectory of fire-born aerosols in response to atmospheric deposition. Calculations of carbon released during the fire versus carbon absorbed by the oceanic phytoplankton bloom suggest that they were nearly equal. This finding illustrates the critical role of the oceans in mitigating natural and anthropogenic carbon dioxide releases to the atmosphere, which are a primary driver of climate change. © 2021 The Authors

Typhoons are assumed to stimulate ocean primary production through the upward mixing of nutrients into the surface ocean, based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, seen on occasion by satellites, more often is undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the Northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. Contrary to the prevailing dogma, the results show that typhoons likely have limited effect on net ocean primary production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper ocean productivity can only be achieved with ocean observing robots dedicated to high-resolution temporal sampling in the path of storms.

Typhoons are assumed to stimulate ocean primary production through the upward mixing of nutrients into the surface ocean, based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, seen on occasion by satellites, more often is undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the Northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. Contrary to the prevailing dogma, the results show that typhoons likely have limited effect on net ocean primary production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper ocean productivity can only be achieved with ocean observing robots dedicated to high-resolution temporal sampling in the path of storms.

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chen, S., Wells, M. L., Huang, R. X., Xue, H., Xi, J., & Chai, F. Episodic subduction patches in the western North Pacific identified from BGC-Argo float data. Biogeosciences, 18(19), (2021): 5539–5554, https://doi.org/10.5194/bg-18-5539-2021., Subduction associated with mesoscale eddies is an important but difficult-to-observe process that can efficiently export carbon and oxygen to the mesopelagic zone (100–1000 dbar). Using a novel BGC-Argo dataset covering the western North Pacific (20–50∘ N, 120–180∘ E), we identified imprints of episodic subduction using anomalies in dissolved oxygen and spicity, a water mass marker. These subduction patches were present in 4.0 % (288) of the total profiles (7120) between 2008 and 2019, situated mainly in the Kuroshio Extension region between March and August (70.6 %). Roughly 31 % and 42 % of the subduction patches were identified below the annual permanent pycnocline depth (300 m vs. 450 m) in the subpolar and subtropical regions, respectively. Around half (52 %) of these episodic events injected oxygen-enriched waters below the maximum annual permanent thermocline depth (450 dbar), with >20 % occurring deeper than 600 dbar. Subduction patches were detected during winter and spring when mixed layers are deep. The oxygen inventory within these subductions is estimated to be on the order of 64 to 152 g O2/m2. These mesoscale events would markedly increase oxygen ventilation as well as carbon removal in the region, both processes helping to support the nutritional and metabolic demands of mesopelagic organisms. Climate-driven patterns of increasing eddy kinetic energies in this region imply that the magnitude of these processes will grow in the future, meaning that these unexpectedly effective small-scale subduction processes need to be better constrained in global climate and biogeochemical models., This work was supported by the National Natural Science Foundation of China (NSFC) projects (grant nos. 41906159, 42030708, and 41730536), the Scientific Research Fund of the Second Institute of Oceanography MNR (grant no. 14283), and the Marine S&T Fund of Shandong Province for the Pilot National Laboratory for Marine Science and Technology (Qingdao) (grant no. 2018SDKJ0206).

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chen, S., Wells, M. L., Huang, R. X., Xue, H., Xi, J., & Chai, F. Episodic subduction patches in the western North Pacific identified from BGC-Argo float data. Biogeosciences, 18(19), (2021): 5539–5554, https://doi.org/10.5194/bg-18-5539-2021., Subduction associated with mesoscale eddies is an important but difficult-to-observe process that can efficiently export carbon and oxygen to the mesopelagic zone (100–1000 dbar). Using a novel BGC-Argo dataset covering the western North Pacific (20–50∘ N, 120–180∘ E), we identified imprints of episodic subduction using anomalies in dissolved oxygen and spicity, a water mass marker. These subduction patches were present in 4.0 % (288) of the total profiles (7120) between 2008 and 2019, situated mainly in the Kuroshio Extension region between March and August (70.6 %). Roughly 31 % and 42 % of the subduction patches were identified below the annual permanent pycnocline depth (300 m vs. 450 m) in the subpolar and subtropical regions, respectively. Around half (52 %) of these episodic events injected oxygen-enriched waters below the maximum annual permanent thermocline depth (450 dbar), with >20 % occurring deeper than 600 dbar. Subduction patches were detected during winter and spring when mixed layers are deep. The oxygen inventory within these subductions is estimated to be on the order of 64 to 152 g O2/m2. These mesoscale events would markedly increase oxygen ventilation as well as carbon removal in the region, both processes helping to support the nutritional and metabolic demands of mesopelagic organisms. Climate-driven patterns of increasing eddy kinetic energies in this region imply that the magnitude of these processes will grow in the future, meaning that these unexpectedly effective small-scale subduction processes need to be better constrained in global climate and biogeochemical models., This work was supported by the National Natural Science Foundation of China (NSFC) projects (grant nos. 41906159, 42030708, and 41730536), the Scientific Research Fund of the Second Institute of Oceanography MNR (grant no. 14283), and the Marine S&T Fund of Shandong Province for the Pilot National Laboratory for Marine Science and Technology (Qingdao) (grant no. 2018SDKJ0206).

Typhoons are assumed to stimulate ocean primary production through the upward mixing of nutrients into the surface ocean, based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, seen on occasion by satellites, more often is undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the Northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. Contrary to the prevailing dogma, the results show that typhoons likely have limited effect on net ocean primary production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper ocean productivity can only be achieved with ocean observing robots dedicated to high-resolution temporal sampling in the path of storms.

Typhoons are assumed to stimulate ocean primary production through the upward mixing of nutrients into the surface ocean, based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, seen on occasion by satellites, more often is undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the Northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. Contrary to the prevailing dogma, the results show that typhoons likely have limited effect on net ocean primary production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper ocean productivity can only be achieved with ocean observing robots dedicated to high-resolution temporal sampling in the path of storms.

Modeling binary star populations is critical to linking the theories of star formation and stellar evolution with observations. In order to test these theories, we need accurate models of observable binary populations. The Kepler Eclipsing Binary Catalog (KEBC), with its estimated $>$90% completeness, provides an observational anchor on binary population models. In this work we present the results of a new forward-model of the binary star population in the Kepler field. The forward-model takes a single star population from a model of the galaxy and pairs the stars into binaries by applying the constraints on the population from the results of observational binary population surveys such as arXiv:1007.0414 and arXiv:1303.3028. A synthetic binary population is constructed from the initial distributions of orbital parameters. We identify the eclipsing binary sample from the generated binary star population and compare this with the observed sample of eclipsing binaries contained in the KEBC. Finally, we update the distributions of the synthetic population and repeat the process until the synthetic eclipsing binary sample agrees with the KEBC. The end result of this process is a model of the underlying binary star population that has been fit to observations. We find that for fixed flat mass ratio and eccentricity input distributions, the binary period distribution is logarithmically flat above $\sim$3.2d. With additional constraints on distributions from observations, we can further adjust the synthetic binary population by relaxing other input constraints, such as mass ratio and eccentricity., Comment: 20 pages, 14 figures, submitted to ApJS and accepted on December 20, 2020

There is increasing concern that accelerating environmental change attributed to human-induced warming of the planet may substantially alter the patterns, distribution and intensity of Harmful Algal Blooms (HABs). Changes in temperature, ocean acidification, precipitation, nutrient stress or availability, and the physical structure of the water column all influence the productivity, composition, and global range of phytoplankton assemblages, but large uncertainty remains about how integration of these climate drivers might shape future HABs. Presented here are the collective deliberations from a symposium on HABs and climate change where the research challenges to understanding potential linkages between HABs and climate were considered, along with new research directions to better define these linkages. In addition to the likely effects of physical (temperature, salinity, stratification, light, changing storm intensity), chemical (nutrients, ocean acidification), and biological (grazer) drivers on microalgae (senso lato), symposium participants explored more broadly the subjects of cyanobacterial HABs, benthic HABs, HAB effects on fisheries, HAB modelling challenges, and the contributions that molecular approaches can bring to HAB studies. There was consensus that alongside traditional research, HAB scientists must set new courses of research and practices to deliver the conceptual and quantitative advances required to forecast future HAB trends. These different practices encompass laboratory and field studies, long-term observational programs, retrospectives, as well as the study of socioeconomic drivers and linkages with aqua culture and fisheries. In anticipation of growing HAB problems, research on potential mitigation strategies should be a priority. It is recommended that a substantial portion of HAB research among laboratories be directed collectively at a small sub-set of HAB species and questions in order to fast-track advances in our understanding. Climat

With the nexus of climate change, globalization, and dwindling marine fishes, more attention is being paid to the increasing global burden of ciguatera fish poisoning (CFP) and the development of appropriate strategies for intervention, especially in endemic areas such as the South Pacific Islands and the Caribbean Sea. CFP is a non-bacterial food poisoning event with outbreaks around the world in which fish concentrate a potent neurotoxin (ciguatoxin) in their organs and tissues from inadvertent feeding on toxic benthic algal species. Outbreaks are frequent in endemic areas in the tropics and semi-tropics with developed corals and benthic fish fisheries. Occurrences are also present in non-endemic areas where contaminated fish are exported for consumption. Local populations on tropical or semi-tropical islands are particularly vulnerable to this poisoning through the consumption of ciguatoxin-contaminated fish. Here, we consider the pecuniary costs of population exposure to CFP using two published studies as a template for developing a case study of the eco-socio-economic cost model in island nations

The consequences of Harmful Algal Blooms (HABs) fall into two primary groups: categorical effects on human and ecosystem health, and the varied socio-economic consequences stemming from their occurrence. The effects on human health tend to be limited in much of the developed world due to extensive and costly monitoring practices linked to the implementation of governmental regulations that minimize, and ideally prevent, the transfer of toxic seafood to consumers. Socio-economic impacts, on the other hand, transpire with every HAB event, differ in their character and magnitude, and to date have been poorly quantified, particularly for indirect impacts. [...]

There is increasing concern that accelerating environmental change attributed to human-induced warming of the planet may substantially alter the patterns, distribution and intensity of Harmful Algal Blooms (HABs). Changes in temperature, ocean acidification, precipitation, nutrient stress or availability, and the physical structure of the water column all influence the productivity, composition, and global range of phytoplankton assemblages, but large uncertainty remains about how integration of these climate drivers might shape future HABs. Presented here are the collective deliberations from a symposium on HABs and climate change where the research challenges to understanding potential linkages between HABs and climate were considered, along with new research directions to better define these linkages. In addition to the likely effects of physical (temperature, salinity, stratification, light, changing storm intensity), chemical (nutrients, ocean acidification), and biological (grazer) drivers on microalgae (senso lato), symposium participants explored more broadly the subjects of cyanobacterial HABs, benthic HABs, HAB effects on fisheries, HAB modelling challenges, and the contributions that molecular approaches can bring to HAB studies. There was consensus that alongside traditional research, HAB scientists must set new courses of research and practices to deliver the conceptual and quantitative advances required to forecast future HAB trends. These different practices encompass laboratory and field studies, long-term observational programs, retrospectives, as well as the study of socioeconomic drivers and linkages with aquaculture and fisheries. In anticipation of growing HAB problems, research on potential mitigation strategies should be a priority. It is recommended that a substantial portion of HAB research among laboratories be directed collectively at a small sub-set of HAB species and questions in order to fast-track advances in our understanding. Climate

Global demand for macroalgal and microalgal foods is growing, and algae are increasingly being consumed for functional benefits beyond the traditional considerations of nutrition and health. There is substantial evidence for the health benefits of algal-derived food products, but there remain considerable challenges in quantifying these benefits, as well as possible adverse effects. First, there is a limited understanding of nutritional composition across algal species, geographical regions, and seasons, all of which can substantially affect their dietary value. The second issue is quantifying which fractions of algal foods are bioavailable to humans, and which factors influence how food constituents are released, ranging from food preparation through genetic differentiation in the gut microbiome. Third is understanding how algal nutritional and functional constituents interact in human metabolism. Superimposed considerations are the effects of harvesting, storage, and food processing techniques that can dramatically influence the potential nutritive value of algal-derived foods. We highlight this rapidly advancing area of algal science with a particular focus on the key research required to assess better the health benefits of an alga or algal product. There are rich opportunities for phycologists in this emerging field, requiring exciting new experimental and collaborative approaches.

Global demand for macroalgal and microalgal foods is growing, and algae are increasingly being consumed for functional benefits beyond the traditional considerations of nutrition and health. There is substantial evidence for the health benefits of algal-derived food products, but there remain considerable challenges in quantifying these benefits, as well as possible adverse effects. First, there is a limited understanding of nutritional composition across algal species, geographical regions, and seasons, all of which can substantially affect their dietary value. The second issue is quantifying which fractions of algal foods are bioavailable to humans, and which factors influence how food constituents are released, ranging from food preparation through genetic differentiation in the gut microbiome. Third is understanding how algal nutritional and functional constituents interact in human metabolism. Superimposed considerations are the effects of harvesting, storage, and food processing techniques that can dramatically influence the potential nutritive value of algal-derived foods. We highlight this rapidly advancing area of algal science with a particular focus on the key research required to assess better the health benefits of an alga or algal product. There are rich opportunities for phycologists in this emerging field, requiring exciting new experimental and collaborative approaches.

Light curves of astrophysical objects frequently contain strictly periodic signals. In those cases we can use that property to aid the detrending algorithm to fully disentangle an unknown periodic signal and an unknown baseline signal with no power at that period. The periodic signal is modeled as a discrete probability distribution function (pdf), while the baseline signal is modeled as a residual timeseries. Those two components are disentangled by minimizing the length of the residual timeseries w.r.t. the per-bin pdf fluxes. We demonstrate the use of the algorithm on a synthetic case, on the eclipsing binary KIC 3953981 and on the eccentric ellipsoidal variable KIC 3547874. We further discuss the parameters and the limitations of the algorithm and speculate on the two most common use cases: detrending the periodic signal of interest and measuring the dependence of instrumental response on controlled instrumental variables. A more sophisticated version of the algorithm is released as open source on github and available via pip., Comment: 9 pages, 2 figures; code available from https://github.com/aprsa/dips and via pip3

Light curves of astrophysical objects frequently contain strictly periodic signals. In those cases we can use that property to aid the detrending algorithm to fully disentangle an unknown periodic signal and an unknown baseline signal with no power at that period. The periodic signal is modeled as a discrete probability distribution function (pdf), while the baseline signal is modeled as a residual timeseries. Those two components are disentangled by minimizing the length of the residual timeseries w.r.t. the per-bin pdf fluxes. We demonstrate the use of the algorithm on a synthetic case, on the eclipsing binary KIC 3953981 and on the eccentric ellipsoidal variable KIC 3547874. We further discuss the parameters and the limitations of the algorithm and speculate on the two most common use cases: detrending the periodic signal of interest and measuring the dependence of instrumental response on controlled instrumental variables. A more sophisticated version of the algorithm is released as open source on github and available via pip., Comment: 9 pages, 2 figures; code available from https://github.com/aprsa/dips and via pip3

Climate change pressures will influence marine planktonic systems globally, and it is conceivable that harmful algal blooms may increase in frequency and severity. These pressures will be manifest as alterations in temperature, stratification, light, ocean acidification, precipitation-induced nutrient inputs, and grazing, but absence of fundamental knowledge of the mechanisms driving harmful algal blooms frustrates most hope of forecasting their future prevalence. Summarized here is the consensus of a recent workshop held to address what currently is known and not known about the environmental conditions that favor initiation and maintenance of harmful algal blooms. There is expectation that harmful algal bloom (HAB) geographical domains should expand in some cases, as will seasonal windows of opportunity for harmful algal blooms at higher latitudes. Nonetheless there is only basic information to speculate upon which regions or habitats HAB species may be the most resilient or susceptible. Moreover, current research strategies are not well suited to inform these fundamental linkages. There is a critical absence of tenable hypotheses for how climate pressures mechanistically affect HAB species, and the lack of uniform experimental protocols limits the quantitative cross-investigation comparisons essential to advancement. A HAB "best practices" manual would help foster more uniform research strategies and protocols, and selection of a small target list of model HAB species or isolates for study would greatly promote the accumulation of knowledge. Despite the need to focus on keystone species, more studies need to address strain variability within species, their responses under multifactorial conditions, and the retrospective analyses of long-term plankton and cyst core data; research topics that are departures from the norm. Examples of some fundamental unknowns include how larger and more frequent extreme weather events may break down natural biogeographic barriers

The Cepheid Period-Luminosity law is a key rung on the extragalactic distance ladder. However, numerous Cepheids are known to undergo period variations. Monitoring, refining, and understanding these period variations allows us to better determine the parameters of the Cepheids themselves and of the instability strip in which they reside, and to test models of stellar evolution. VZ Cyg, a classical Cepheid pulsating at $\sim$4.864 days, has been observed for over 100 years. Combining data from literature observations, the Kilodegree Extremely Little Telescope (KELT) transit survey, and new targeted observations with the Robotically Controlled Telescope (RCT) at Kitt Peak, we find a period change rate of $dP/dt = -0.0642 \pm 0.0018$ sec yr$^{-1}$. However, when only the recent observations are examined, we find a much higher period change rate of $dP/dt = - 0.0923 \pm 0.0110$ sec yr$^{-1}$. This higher rate could be due to an apparent long-term (P $\approx$ 26.5 yr) cyclic period variation. The possible interpretations of this single Cepheid's complex period variations underscore both the need to regularly monitor pulsating variables, and the important benefits that photometric surveys such as KELT can have on the field. Further monitoring of this interesting example of Cepheid variability is recommended to confirm and better understand the possible cyclic period variations. Further, Cepheid timing analyses are necessary to fully understand their current behaviors and parameters, as well as their evolutionary histories., Comment: 10 pages including 8 figures, accepted for publication in AJ

In this work we quantify the performance of $LSST$ on the detection of eclipsing binaries. We use $Kepler$ observed binaries to create a large sample of simulated pseudo-$LSST$ binary light curves. From these light curves, we attempt to recover the known binary signal. The success rate of period recovery from the pseudo-$LSST$ light curves is indicative of $LSST$'s expected performance. Using an off-the-shelf Analysis of Variance (AoV) routine, we successfully recover 71% of the targets in our sample. We examine how the binary period impacts recovery success and see that for periods longer than 10~days the chance of successful binary recovery drops below 50%., Comment: to be published in Publications of the Astronomical Society of the Pacific

The Cepheid Period-Luminosity law is a key rung on the extragalactic distance ladder. However, numerous Cepheids are known to undergo period variations. Monitoring, refining, and understanding these period variations allows us to better determine the parameters of the Cepheids themselves and of the instability strip in which they reside, and to test models of stellar evolution. VZ Cyg, a classical Cepheid pulsating at $\sim$4.864 days, has been observed for over 100 years. Combining data from literature observations, the Kilodegree Extremely Little Telescope (KELT) transit survey, and new targeted observations with the Robotically Controlled Telescope (RCT) at Kitt Peak, we find a period change rate of $dP/dt = -0.0642 \pm 0.0018$ sec yr$^{-1}$. However, when only the recent observations are examined, we find a much higher period change rate of $dP/dt = - 0.0923 \pm 0.0110$ sec yr$^{-1}$. This higher rate could be due to an apparent long-term (P $\approx$ 26.5 yr) cyclic period variation. The possible interpretations of this single Cepheid's complex period variations underscore both the need to regularly monitor pulsating variables, and the important benefits that photometric surveys such as KELT can have on the field. Further monitoring of this interesting example of Cepheid variability is recommended to confirm and better understand the possible cyclic period variations. Further, Cepheid timing analyses are necessary to fully understand their current behaviors and parameters, as well as their evolutionary histories., Comment: 10 pages including 8 figures, accepted for publication in AJ

In this work we quantify the performance of $LSST$ on the detection of eclipsing binaries. We use $Kepler$ observed binaries to create a large sample of simulated pseudo-$LSST$ binary light curves. From these light curves, we attempt to recover the known binary signal. The success rate of period recovery from the pseudo-$LSST$ light curves is indicative of $LSST$'s expected performance. Using an off-the-shelf Analysis of Variance (AoV) routine, we successfully recover 71% of the targets in our sample. We examine how the binary period impacts recovery success and see that for periods longer than 10~days the chance of successful binary recovery drops below 50%., Comment: to be published in Publications of the Astronomical Society of the Pacific

The Kepler satellite provides a unique window into stellar temporal variability by observing a wide variety of stars with multi-year, near-continuous, high precision, optical photometric time series. While most Kepler targets are faint stars with poorly known physical properties, many unexpected discoveries should result from a long photometric survey of such a large area of sky. During our Kepler Guest Observer programs that monitored late-type stars for starspot and flaring variability, we discovered a previously unknown dwarf nova that lies within a few arcseconds of the mid-G dwarf star KIC 5438845. This dwarf nova underwent nine outbursts over a 4 year time span. The two largest outbursts lasted similar to 17-18 days and show strong modulations with a 110.8 minute period and a declining amplitude during the outburst decay phase. These properties are characteristic of an SU UMa-type cataclysmic variable. By analogy with other dwarf nova light curves, we associate the 110.8 minute (1.847 hr) period with the superhump period, close to but slightly longer than the orbital period of the binary. No precursor outbursts are seen before the super-outbursts and the overall super-outburst morphology corresponds to Osaki & Meyer "Case B" outbursts, which are initiated when the outer edge of the disk reaches the tidal truncation radius. "Case B" outbursts are rare within the Kepler light curves of dwarf novae. The dwarf nova is undergoing relatively slow mass transfer, as evidenced by the long intervals between outbursts, but the mass transfer rate appears to be steady, because the smaller "normal" outbursts show a strong correlation between the integrated outburst energy and the elapsed time since the previous outburst. At super-outburst maximum the system was at V similar to 18, but in quiescence it is fainter than V similar to 22, which will make any detailed quiescent follow-up of this system difficult.

CHDS State/Local, Accidental or intentional release of radiation may result in catastrophic consequences to urban and suburban populations. Any emergency response is compromised by insufficiently detailed protocols, and qualitative or quantitative wants in equipment and training. These challenges are no less acute for Sacramento County which is an archetype of at-risk suburban and urban settings. Recognized standards in critical patient care illustrate the need for specific considerations for radiological contaminated patients in a response protocol. Current practices in Sacramento require patient decontamination prior to treatment or transport. This may adversely affect survival profiles, despite national and international standards which specifically provide for consideration of alternate procedures. Radiation responses require a systems approach, whereby all work collaboratively toward a common goal. Incident commanders must appreciate their role in a radiation response, and how to incorporate the response into a unified multi-jurisdictional, unified command. Additionally, an essential component of any radiation response protocol is to decrease the associated "fear" of radiation in the general public as well as emergency responders. Best practices research, and recommendations at local, state, national and international levels are compiled into a usable radiation response protocol which can be utilized in formulating protocols in radiation emergency response., http://archive.org/details/sacramentoregion109452524, Captain, Sacramento Metropolitan Fire District

Udgivelsesdato: September 2009, In September 2004 a large, nearly monospecific diatom bloom of Pseudo-nitzschia cuspidata off the coast of the state of Washington reached cell concentrations of 6.1 × 106 cells L-1 and produced maximum particulate domoic acid (pDA), dissolved domoic acid (dDA), and cellular domoic acid concentrations of 43 nmol L-11, 4 nmol L-1, and 63 pg cell-1, respectively. This bloom co-dominated the phytoplankton assemblage with the euglenoid Eutreptiella sp. in the Juan de Fuca eddy region, a known initiation site for toxigenic Pseudo-nitzschia blooms. Two isolates of P. cuspidata collected during separate cruises produced domoic acid (DA) in culture. During the September 2004 survey, 84% of the stations (n = 98) had detectable Pseudo-nitzschia and 78% had detectable pDA. There were no significant correlations between either pDA or cellular DA and ambient concentrations of macronutrients; however, when considering only those stations where Pseudo-nitzschia was present, pDA was positively correlated with chlorophyll a and negatively correlated with temperature (p < 0.01) at both 1- and 5-m depths. Correlations between cellular DA concentrations and total bacteria or cyanobacteria abundances were not significant. Variable ratios of pDA:dDA in the eddy region suggest that DA release was under cellular regulation by Pseudo-nitzschia. Stations where dissolved Fe concentrations were limiting (,0.5 nmol L-1) had the highest Pseudo-nitzschia abundances and pDA and cellular DA values. These results provide enticing field evidence of the role of Fe limitation in controlling cellular DA levels.

Udgivelsesdato: September 2009, In September 2004 a large, nearly monospecific diatom bloom of Pseudo-nitzschia cuspidata off the coast of the state of Washington reached cell concentrations of 6.1 × 106 cells L-1 and produced maximum particulate domoic acid (pDA), dissolved domoic acid (dDA), and cellular domoic acid concentrations of 43 nmol L-11, 4 nmol L-1, and 63 pg cell-1, respectively. This bloom co-dominated the phytoplankton assemblage with the euglenoid Eutreptiella sp. in the Juan de Fuca eddy region, a known initiation site for toxigenic Pseudo-nitzschia blooms. Two isolates of P. cuspidata collected during separate cruises produced domoic acid (DA) in culture. During the September 2004 survey, 84% of the stations (n = 98) had detectable Pseudo-nitzschia and 78% had detectable pDA. There were no significant correlations between either pDA or cellular DA and ambient concentrations of macronutrients; however, when considering only those stations where Pseudo-nitzschia was present, pDA was positively correlated with chlorophyll a and negatively correlated with temperature (p < 0.01) at both 1- and 5-m depths. Correlations between cellular DA concentrations and total bacteria or cyanobacteria abundances were not significant. Variable ratios of pDA:dDA in the eddy region suggest that DA release was under cellular regulation by Pseudo-nitzschia. Stations where dissolved Fe concentrations were limiting (,0.5 nmol L-1) had the highest Pseudo-nitzschia abundances and pDA and cellular DA values. These results provide enticing field evidence of the role of Fe limitation in controlling cellular DA levels.

Our long term research goal is to ascertain the nature and magnitude of optical effects (absorbance / fluorescence / scattering) in surface seawaters associated with the production and cycling of marine colloidal organic matter. We are particularly interested in determining how these effects are driven or modulated by the productivity dynamics of phytoplankton and marine heterotrophic bacteria in coastal regions not directly influenced by high riverine inputs of terrestrially-derived materials.

Our long term research goal is to ascertain the nature and magnitude of optical effects (absorbance / fluorescence / scattering) in surface seawaters associated with the production and cycling of marine colloidal organic matter. We are particularly interested in determining how these effects are driven or modulated by the productivity dynamics of phytoplankton and marine heterotrophic bacteria in coastal regions not directly influenced by high riverine inputs of terrestrially-derived materials., The original document contains color images.

Our long term research goal is to ascertain the nature and magnitude of optical effects (absorbance / fluorescence / scattering) in surface seawaters associated with the production and cycling of marine colloidal organic matter. We are particularly interested in determining how these effects are driven or modulated by the productivity dynamics of phytoplankton and marine heterotrophic bacteria in coastal regions not directly influenced by high riverine inputs of terrestrially-derived materials., The original document contains color images. Presented at the cooperation with Maine University, Walpole, ME.

Accidental or intentional release of radiation may result in catastrophic consequences to urban and suburban populations. Any emergency response is compromised by insufficiently detailed protocols, and qualitative or quantitative wants in equipment and training. These challenges are no less acute for Sacramento County which is an archetype of at-risk suburban and urban settings. Recognized standards in critical patient care illustrate the need for specific considerations for radiological contaminated patients in a response protocol. Current practices in Sacramento require patient decontamination prior to treatment or transport. This may adversely affect survival profiles, despite national and international standards which specifically provide for consideration of alternate procedures. Radiation responses require a systems approach, whereby all work collaboratively toward a common goal. Incident commanders must appreciate their role in a radiation response, and how to incorporate the response into a unified multi-jurisdictional, unified command. Additionally, an essential component of any radiation response protocol is to decrease the associated "fear" of radiation in the general public as well as emergency responders. Best practices research, and recommendations at local, state, national and international levels are compiled into a usable radiation response protocol which can be utilized in formulating protocols in radiation emergency response.

My long term research goal is to ascertain the nature and magnitude of optical effects (absorbance / fluorescence / scattering) in surface seawaters associated with the production and cycling of marine colloidal organic matter. I am particularly interested in determining how these effects are driven or modulated by the productivity dynamics of phytoplankton and marine heterotrophic bacteria. Marine chromophoric dissolved organic matter (CDOM) imparts highly variable optical signatures in surface waters over short spatial and temporal scales for reasons not yet understood. While considerable research efforts are currently underway on the specific absorption and fluorescence characteristics of the bulk CDOM, my primary objective is to follow the chromophoric signatures of different molecular weight fractions to determine if the production and removal of colloidal organic matter contributes to the high variability in bulk CDOM. We know that a significant fraction (10-40%) of non-living dissolved organic matter resides in the colloidal size fraction (1-1000 nm) (Chen and Schnitzer 1989; Benner et al. 1992; Buesseler et al. 1995), and that this fraction is very reactive to both bio-degradation (to soluble substances) (Benner et al. 1992) and aggregation (to large sinking particles)(Baskaran et al. 1992; Moran and Buesseler 1992). The challenge is to determine to what extent these dynamic, opposing processes influence the behavior of CDOM in surface seawaters, and how these biogeochemical effects interweave with photochemical degradation pathways., See also ADM002252.

There is currently no interdisciplinary study which surveys the U.S. Air Force's philosophical and organizational responses to the problems of combat fatigue or psychological collapse during the history of air war. While stress and battle shock casualties are topics of concern inside the military medical community, the subjects receive little attention from contemporary aircrew, or, more importantly, among Air Force squadron and wing commanders. This study begins with a brief look at the human dimension of airpower, examines some of the characteristics of airmen, and reviews the risky nature of the air combat environment. It goes on to describe the impact of stress on airmen and covers the Air Force's historical responses to them. More than a simple survey, however, this monograph will make specific recommendations regarding the education and training of commanders, officers, and airmen so they will be equipped to deal realistically with the potential problem of stress related casualties.

This thesis investigates the unique nature of aerial warfare and the men who participated in it by analysing aircrew selection, reaction to combat, adaptability to stress, morale, leadership, and combat effectiveness. Moreover, it provides the first detailed examination of the sensitive subject called 'Lack of Moral Fibre.' First-hand reflections of combat airmen, published materials, reports and official documents are used to compare the efforts of the U.S. Eighth Air Force and R.A.F. Bomber Command. There is an important reason for this comparative method. All too often the strategic bombing offensive against Germany is regarded as two separate campaigns. In fact, it was very much a common enterprise. Although the Allied effort featured two air forces, two different philosophical concepts and two distinct approaches to the same problem, both organisations were committed essentially to achieve a central objective. A comparative method therefore makes it possible to gain some genuine insights into the nature of air combat and its impact on aviators.