576 research outputs found
The Fundamental Plane of Black Hole Accretion and its Use as a Black Hole-Mass Estimator
We present an analysis of the fundamental plane of black hole accretion, an
empirical correlation of the mass of a black hole (), its 5 GHz radio
continuum luminosity (), and its 2-10 keV X-ray power-law
continuum luminosity (). We compile a sample of black holes with primary,
direct black hole-mass measurements that also have sensitive,
high-spatial-resolution radio and X-ray data. Taking into account a number of
systematic sources of uncertainty and their correlations with the measurements,
we use Markov chain Monte Carlo methods to fit a mass-predictor function of the
form . Our best-fit results are , , and
with the natural logarithm of the Gaussian intrinsic scatter in the log-mass
direction . This result is a
significant improvement over our earlier mass scaling result because of the
increase in active galactic nuclei sample size (from 18 to 30), improvement in
our X-ray binary sample selection, better identification of Seyferts, and
improvements in our analysis that takes into account systematic uncertainties
and correlated uncertainties. Because of these significant improvements, we are
able to consider potential influences on our sample by including all sources
with compact radio and X-ray emission but ultimately conclude that the
fundamental plane can empirically describe all such sources. We end with advice
for how to use this as a tool for estimating black hole masses.Comment: ApJ Accepted. Online interactive version of Figure 7 available at
http://kayhan.astro.lsa.umich.edu/supplementary_material/fp
Perceptions and Preferences of Extension Programming and Sources Among Extension Users and Non-Users: 10 Kansas Counties
County Extension personnel are challenged to serve the public while facing changing population density and diversity. Moreover, needs and satisfaction vary among Extension clients and non-clients. With this in mind, 10 of the most populous counties in Kansas, with the aid of a university researcher, conducted an evaluation to determine programming needs of both clients and non-clients. Findings indicate that non-clients and clients prioritize programming differently and prefer different delivery mechanisms. The results have allowed these counties to tailor their programming and marketing efforts to these two unique groups, while also serving as a basis for a collective marketing plan
Nursing transfer of accountability at the bedside: partnering with patients to pilot a new initiative in Ontario community hospitals
The transfer of accountability (TOA) for a patient from one nurse to another at change of shift is an important opportunity to exchange essential patient care information, as well as to enhance the safety and quality of patient care. This study was undertaken to explore nurses’, patients’ and family members’ perceptions associated with the implementation of bedside nurse to nurse TOA. Focus groups were conducted pre-implementation (two with nurses and two with patients and family members) and post-implementation (six with nurses and two with patients and family members). The focus groups were audio-recorded, transcribed and analysed using directed content analysis. Findings were divided into positive outcomes and challenges to bedside nurse to nurse TOA. Positive outcomes included increased patient safety, more informed patients more consistent use of whiteboards in the patient rooms, better engagement with family via the whiteboard and increased family involvement, confirmation of information between nurses, increased accountability between nurses, and personal introduction/icebreaker of the new nurse. The inclusion of the Patient Partners on the project team was a key success factor for the project. Challenges included a perception of lengthened time required for TOA and increased workload, lack of privacy and potential breaches of confidentiality, patient fear and lack of comprehension, lack of clarity in TOA processes, and inconsistent application of the procedures. Hospital administrators and nurse leaders can use these findings to anticipate and understand change associated with bedside TOA as seen by both nurses and patients/families
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Supporting Student Knowledge Using Formative Assessment and Universal Design for Learning Expression
This article demonstrates an approach for teachers to use outcomes from activities using the universal design for learning expression principle to evaluate student knowledge in content areas. Based on the student’s level of explanation using a variety of expression methods, teachers can determine whether students need additional support for re-teaching a concept or whether students are ready for additional practice or challenge. Various levels of technology can be used for formatively assessing student understanding, from no technology (e.g., paper and pencil) to mid- or high-technology tools found in most classrooms, including computers and tablets
Renewal in the cognitive and emotional domains: comparing novelty-facilitated extinction with counterconditioning and extinction
The primary file is a ReadMe file and additional file is the dataset
Population structure of Dungeness crab (Cancer magister
ABSTRACT Population structure of Dungeness crab (Cancer magister) from British Columbia was evaluated from a survey of variation of eight microsatellite loci in eight populations. Genetic differentiation among the populations surveyed was observed, with the mean F st for all loci 0.031 (SD ¼ 0.007). The Alison Sound population in the British Columbia central coast displayed less genetic variation and was distinct from all other populations in British Columbia, with pairwise F st values >0.12, over 20 times the differentiation in other comparisons. The results were consistent with a high level of retention of larval crabs within Alison Sound, owing to reduced water exchange between the sound and adjacent waters. There was no evidence for an isolation by distance model of population structure of Dungeness crab in British Columbia, but there was some indication of differentiation between a west coast Vancouver Island population and a population adjacent to the southern Strait of Georgia
UNC-98 links an integrin-associated complex to thick filaments in Caenorhabditis elegans muscle
Focal adhesions are multiprotein assemblages that link cells to the extracellular matrix. The transmembrane protein, integrin, is a key component of these structures. In vertebrate muscle, focal adhesion–like structures called costameres attach myofibrils at the periphery of muscle cells to the cell membrane. In Caenorhabditis elegans muscle, all the myofibrils are attached to the cell membrane at both dense bodies (Z-disks) and M-lines. Clustered at the base of dense bodies and M-lines, and associated with the cytoplasmic tail of β-integrin, is a complex of many proteins, including UNC-97 (vertebrate PINCH). Previously, we showed that UNC-97 interacts with UNC-98, a 37-kD protein, containing four C2H2 Zn fingers, that localizes to M-lines. We report that UNC-98 also interacts with the C-terminal portion of a myosin heavy chain. Multiple lines of evidence support a model in which UNC-98 links integrin-associated proteins to myosin in thick filaments at M-lines
Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations
Malignant melanotic nerve sheath tumor (MMNST) is a rare and potentially aggressive lesion defined in the 2021 WHO Classification of Tumors of the Central Nervous System. MMNST demonstrate overlapping histologic and clinical features of schwannoma and melanoma. MMNST often harbor PRKAR1A mutations, especially within the Carney Complex. We present a case of aggressive MMNST of the sacral region in a 48-year-old woman. The tumor contained PRKAR1A frameshift pR352Hfs*89, KMT2C splice site c.7443-1G>T and GNAQ p.R183L missense mutations, as well as BRAF and MYC gains. Genomic DNA methylation analysis using the Illumina 850K EpicBead chip revealed that the lesion did not match an established methylation class; however, uniform manifold approximation and projection (UMAP) placed the tumor very near, or with, schwannomas. The tumor expressed PD-L1, and the patient was treated with radiation and immune checkpoint inhibitors following en bloc resection. Although she had symptomatic improvement, she suffered early disease progression with local recurrence, and distant metastases, and died 18 months after resection. It has been suggested that the presence of GNAQ mutations can differentiate leptomeningeal melanocytic neoplasms and uveal melanoma from MMNST. This case and others demonstrate that GNAQ mutations may exist in malignant nerve sheath tumors; that GNAQ and PRKAR1A mutations are not always mutually exclusive and that neither can be used to differentiate MMNST or MPNST from all melanocytic lesions
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