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ABSTRACT Coastal deoxygenation poses a critical threat to tropical coral reefs. Dissolved oxygen (DO) depletion can cause hypoxia-induced stress and mortality in scleractinian corals. Coral hypoxic responses are species-specific and likely modulated by the duration and severity of low-DO conditions, although the physiological mechanisms driving hypoxia tolerance are not fully understood. In this study, the Caribbean corals Acropora cervicornis, Porites astreoides and Siderastrea siderea were exposed to either severe (1.5 mg l−1 DO) or moderate (3.5 mg l−1 DO) deoxygenation or a control treatment (6 mg l−1 DO). All corals survived 2 weeks of deoxygenation but exhibited sublethal changes to coral metabolism after 1- and 2-week exposures, compared with controls. Maximum quantum yield (Fv/Fm) was suppressed after 1 week in both deoxygenation treatments in A. cervicornis, and after 2 weeks in S. siderea and P. astreoides exposed to severe or moderate treatments, respectively. Respiration rates were lower than controls in A. cervicornis and S. siderea after 1 and 2 weeks of severe deoxygenation. The reduced respiration of P. astreoides after 1 week of moderate deoxygenation returned to control levels in week 2. Overall coral metabolic budgets, assessed by ratios of gross photosynthesis to respiration (Pg:R), were more autotrophic, or photosynthesis-dominant, after 1 week of severe deoxygenation in S. siderea and P. astreoides, whereas Pg:R was not significantly different in A. cervicornis between treatments. These results reveal that some corals shift their metabolism to tolerate low-oxygen conditions and avoid bleaching or mortality, indicating that metabolic plasticity is an important aspect of coral resistance to deoxygenation. 

Projects rarely go according to plan, but this is especially true of those that involve multiple institutions and have a significant degree of complexity associated with them. This work relates the experiences an Advanced Technological Education (ATE) project around high value manufacturing. The project was a collaboration with a Texas A&M University and Houston Community College. The project comprised three main aspects: 1) the development of a certificate program in high value manufacturing; 2) offering professional development to working professionals in the area of high value manufacturing; and 3) educating teachers about advanced manufacturing with a goal of recruiting their students into manufacturing careers. This work describes the lessons learned through each of the project aspects. The design of the High Value Manufacturing Certificate Program required close collaboration between both institutions. The issues that arose during this development process included personnel turnover, approval timelines and processes, and agreement on the course content. The authors will relay how they navigated these issues to get the program created and approved. The creation of the professional development program did not involve the community college directly, but was very dependent on recruiting participants. This recruitment proved to be more difficult than the project team expected. The targeting of the professional development program and the development of the curriculum will be discussed. The authors will also highlight the delivery changes they implemented over the two years of the offerings based on participant feedback. The final aspect of the project is the teacher experience with advanced manufacturing. Hosting teachings and determining what content and activities they experience is a somewhat daunting task. The use of an existing University Program and the selection of collaborating faculty will be discussed. Overall, the lessons learned from this project can be an opportunity for new ATE principal investigators (PIs) to learn from the authors’ experiences. It can also help potential ATE PIs craft more realistic and practical proposals. 

Research shows that there is a growing need for skilled workers in the area of advanced manufacturing; this refers to making use of new technologies and advanced processes to produce products that have high value. More importantly, U.S. government employment data reveals that there is lack of supply of skilled workers in the manufacturing sector. Furthermore, it has also been widely cited in industrial literature that there is a concern regarding the job readiness of fresh college graduates and the gaps in skills sets needed to be successful in an industrial setting, especially in the engineering or manufacturing fields. One approach to bridge the skills gap is to provide customized continuing education to current the workforce as per the industry need. This paper presents a case study of such customized continuing education offered by Texas A&M University for oil and gas industry in Houston, Texas. Specifically, as a part of National Science Foundation Advanced Technological Education project, two professional development sessions were organized in the summer of 2018 in Houston targeting the energy industry. Both programs were two-days long and focused on two key aspects of high value manufacturing: manufacturing operations excellence and manufacturing quality excellence. The professional development sessions were focused on materials and inventory planning, production economics, manufacturing quality, non-destructive evaluation, statistical process control, and lean/ sixsigma. The continuing education programs and course materials were developed based on the feedback from the industry advisory board for the Manufacturing Center of Excellence at Houston Community College, which is a collaborating partner on the ATE Grant. As a part of assessment of the programs, industry participants in the both sessions were given comprehensive surveys asking for their feedback on the applicability of the educational sessions. Overall, the participants rated the sessions very highly on the organization and the relevancy of the program topics and learning materials. The participants also felt that they learned new information through these programs. 

The imaging fidelity of the Event Horizon Telescope (EHT) is currently determined by its sparse baseline coverage. In particular, EHT coverage is dominated by long baselines, and is highly sensitive to atmospheric conditions and loss of sites between experiments. The limited short/mid-range baselines especially affect the imaging process, hindering the recovery of more extended features in the image. We present an algorithmic contingency for the absence of well-constrained short baselines in the imaging of compact sources, such as the supermassive black holes observed with the EHT. This technique enforces a specific second moment on the reconstructed image in the form of a size constraint, which corresponds to the curvature of the measured visibility function at zero baseline. The method enables the recovery of information lost in gaps of the baseline coverage on short baselines and enables corrections of any systematic amplitude offsets for the stations giving short-baseline measurements present in the observation. The regularization can use historical source size measurements to constrain the second moment of the reconstructed image to match the observed size. We additionally show that a characteristic size can be derived from available short-baseline measurements, extrapolated from other wavelengths, or estimated without complementary size constraints with parameter searches. We demonstrate the capabilities of this method for both static and movie reconstructions of variable sources. 

Context.The nearby elliptical galaxy M87 contains one of only two supermassive black holes whose emission surrounding the event horizon has been imaged by the Event Horizon Telescope (EHT). In 2018, more than two dozen multi-wavelength (MWL) facilities (from radio toγ-ray energies) took part in the second M87 EHT campaign. Aims.The goal of this extensive MWL campaign was to better understand the physics of the accreting black hole M87*, the relationship between the inflow and inner jets, and the high-energy particle acceleration. Understanding the complex astrophysics is also a necessary first step towards performing further tests of general relativity. Methods.The MWL campaign took place in April 2018, overlapping with the EHT M87* observations. We present a new, contemporaneous spectral energy distribution (SED) ranging from radio to very high-energy (VHE)γ-rays as well as details of the individual observations and light curves. We also conducted phenomenological modelling to investigate the basic source properties. Results.We present the first VHEγ-ray flare from M87 detected since 2010. The flux above 350 GeV more than doubled within a period of ≈36 hours. We find that the X-ray flux is enhanced by about a factor of two compared to 2017, while the radio and millimetre core fluxes are consistent between 2017 and 2018. We detect evidence for a monotonically increasing jet position angle that corresponds to variations in the bright spot of the EHT image. Conclusions.Our results show the value of continued MWL monitoring together with precision imaging for addressing the origins of high-energy particle acceleration. While we cannot currently pinpoint the precise location where such acceleration takes place, the new VHEγ-ray flare already presents a challenge to simple one-zone leptonic emission model approaches, and it emphasises the need for combined image and spectral modelling.