1,663 research outputs found
Discovery of a Photoionized Bipolar Outflow towards the Massive Protostar G45.47+0.05
Massive protostars generate strong radiation feedback, which may help set the
mass they achieve by the end of the accretion process. Studying such feedback
is therefore crucial for understanding the formation of massive stars. We
report the discovery of a photoionized bipolar outflow towards the massive
protostar G45.47+0.05 using high-resolution observations at 1.3 mm with the
Atacama Large Millimeter/Submillimeter Array (ALMA) and at 7 mm with the Karl
G. Jansky Very Large Array (VLA). By modeling the free-free continuum, the
ionized outflow is found to be a photoevaporation flow with an electron
temperature of 10,000 K and an electron number density of ~1.5x10^7 cm^-3 at
the center, launched from a disk of radius of 110 au. H30alpha hydrogen
recombination line emission shows strong maser amplification, with G45 being
one of very few sources to show such millimeter recombination line masers. The
mass of the driving source is estimated to be 30-50 Msun based on the derived
ionizing photon rate, or 30-40 Msun based on the H30alpha kinematics. The
kinematics of the photoevaporated material is dominated by rotation close to
the disk plane, while accelerated to outflowing motion above the disk plane.
The mass loss rate of the photoevaporation outflow is estimated to be
~(2-3.5)x10^-5 Msun/yr. We also found hints of a possible jet embedded inside
the wide-angle ionized outflow with non-thermal emissions. The possible
co-existence of a jet and a massive photoevaporation outflow suggests that, in
spite of the strong photoionization feedback, accretion is still on-going.Comment: Accepted to ApJL. 16 pages, 5 figures, 3 appendix figure
Effects of Co-ingesting Dietary Nitrate and Vitamin C on Nitric Oxide Bioavailability, Blood Pressure, and Cardiovascular Reactivity in Hispanic Females
High blood pressure is a hallmark of chronic disease and is disproportionately prevalent in ethnic minorities. Dietary nitrate has been shown to lower blood pressure via increased nitric oxide (NO), but few studies have examined if combining nitrate with vitamin C (VITC) could have beneficial synergistic effects on blood pressure by augmenting NO, and limited data exist in females. PURPOSE: To investigate if combining nitrate-rich beetroot juice (BR) with VITC could further augment NO bioavailability and improve blood pressure in Hispanic females compared to BR and VITC ingested alone. METHODS: Eight sedentary Hispanic females participated in four conditions to ingest: 1) BR and VITC (BR+VITC), 2) BR and crystal light (BR+CRY), 3) nitrate-depleted BR and VITC (PL+VITC), and 4) PL and CRY (PL+CRY). A blood draw and blood pressure were obtained at rest, followed by a cardiovascular reactivity test. RESULTS: Plasma nitrate was increased in BR+VITC and BR+CRY compared to PL+VITC and PL+CRY (P0.05). Plasma nitrite was increased in BR+VITC and BR+CRY compared to PL+VITC and PL+CRY (P0.05). CONCLUSION: Co-ingestion of dietary nitrate and VITC increased plasma nitrite compared to BR alone, which could indicate augmented NO bioavailability following BR+VITC; however, there was no impact of nitrate supplementation on markers of cardiovascular health
High Quality, Low Cost Egg Incubator for BIC Church in Choma, Zambia
The Egg Incubator team is partnering with the Brethren in Christ Church located in Choma, Zambia to design a high-quality, low-cost chicken egg incubator to supply the pastors and church members with a means of food and income. The design will need to take into account the accessibility and cost of the tools and materials. The current prototype features separate heating and humidity systems, a control system to maintain a set temperature and humidity, and tilting egg racks. The heating system consists of two stovetop coils to produce heat and a fan to transfer it to the air. The humidifier utilizes an atomizer in a pan of water to create a mist that mixes with the hot air to create humidity. The control system uses a proportional integral derivative controller (PID) to keep the temperature at 37 ± 1 °C and the humidity at 60–70%. The egg racks are tilted by a motor that runs every 6 hours to prevent the embryos from sticking to the shell. With a fully functioning prototype, the team has begun to incubate 60 real fertilized eggs. During the 21-day incubation process, a final prototype iteration is being designed and will be built on-site in Zambia in May 2022.
Funding for this work provided by The Collaboratory for Strategic Partnerships and Applied Research.https://mosaic.messiah.edu/engr2022/1004/thumbnail.jp
KELT-11b: A Highly Inflated Sub-Saturn Exoplanet Transiting the V=8 Subgiant HD 93396
We report the discovery of a transiting exoplanet, KELT-11b, orbiting the
bright () subgiant HD 93396. A global analysis of the system shows that
the host star is an evolved subgiant star with K,
, , log , and [Fe/H].
The planet is a low-mass gas giant in a day orbit,
with , , g cm, surface gravity log , and equilibrium temperature K. KELT-11 is the brightest known transiting exoplanet host
in the southern hemisphere by more than a magnitude, and is the 6th brightest
transit host to date. The planet is one of the most inflated planets known,
with an exceptionally large atmospheric scale height (2763 km), and an
associated size of the expected atmospheric transmission signal of 5.6%. These
attributes make the KELT-11 system a valuable target for follow-up and
atmospheric characterization, and it promises to become one of the benchmark
systems for the study of inflated exoplanets.Comment: 15 pages, Submitted to AAS Journal
Transgenic expression of the dicotyledonous pattern recognition receptor EFR in rice leads to ligand-dependent activation of defense responses
Plant plasma membrane localized pattern recognition receptors (PRRs) detect extracellular pathogen-associated molecules. PRRs such as Arabidopsis EFR and rice XA21 are taxonomically restricted and are absent from most plant genomes. Here we show that rice plants expressing EFR or the chimeric receptor EFR::XA21, containing the EFR ectodomain and the XA21 intracellular domain, sense both Escherichia coli- and Xanthomonas oryzae pv. oryzae (Xoo)-derived elf18 peptides at sub-nanomolar concentrations. Treatment of EFR and EFR::XA21 rice leaf tissue with elf18 leads to MAP kinase activation, reactive oxygen production and defense gene expression. Although expression of EFR does not lead to robust enhanced resistance to fully virulent Xoo isolates, it does lead to quantitatively enhanced resistance to weakly virulent Xoo isolates. EFR interacts with OsSERK2 and the XA21 binding protein 24 (XB24), two key components of the rice XA21-mediated immune response. Rice-EFR plants silenced for OsSERK2, or overexpressing rice XB24 are compromised in elf18-induced reactive oxygen production and defense gene expression indicating that these proteins are also important for EFR-mediated signaling in transgenic rice. Taken together, our results demonstrate the potential feasibility of enhancing disease resistance in rice and possibly other monocotyledonous crop species by expression of dicotyledonous PRRs. Our results also suggest that Arabidopsis EFR utilizes at least a subset of the known endogenous rice XA21 signaling components
The Astropy Problem
The Astropy Project (http://astropy.org) is, in its own words, "a community
effort to develop a single core package for Astronomy in Python and foster
interoperability between Python astronomy packages." For five years this
project has been managed, written, and operated as a grassroots,
self-organized, almost entirely volunteer effort while the software is used by
the majority of the astronomical community. Despite this, the project has
always been and remains to this day effectively unfunded. Further, contributors
receive little or no formal recognition for creating and supporting what is now
critical software. This paper explores the problem in detail, outlines possible
solutions to correct this, and presents a few suggestions on how to address the
sustainability of general purpose astronomical software
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