A First Chandra View of the Cool Core Cluster A1668: Offset Cooling and AGN Feedback Cycle

ABSTRACT A variety of large-scale diffuse radio structures have been identified in many clusters with the advent of new state-of-the-art facilities in radio astronomy. Among these diffuse radio structures, radio mini-halos are found in the central regions of cool core clusters. Their origin is still unknown and they are challenging to discover; less than 30 have been published to date. Based on new VLA observations, we confirmed the mini-halo in the massive strong cool core cluster PKS 0745−191 (z = 0.1028) and discovered one in the massive cool core cluster MACS J1447.4+0827 (z = 0.3755). Furthermore, using a detailed analysis of all known mini-halos, we explore the relation between mini-halos and active galactic nucleus (AGN) feedback processes from the central galaxy. We find evidence of strong, previously unknown correlations between mini-halo radio power and X-ray cavity power, and between mini-halo and the central galaxy radio power related to the relativistic jets when spectrally decomposing the AGN radio emission into a component for past outbursts and one for ongoing accretion. Overall, our study indicates that mini-halos are directly connected to the central AGN in clusters, following previous suppositions. We hypothesize that AGN feedback may be one of the dominant mechanisms giving rise to mini-halos by injecting energy into the intra-cluster medium and reaccelerating an old population of particles, while sloshing motion may drive the overall shape of mini-halos inside cold fronts. AGN feedback may therefore not only play a vital role in offsetting cooling in cool core clusters, but may also play a fundamental role in re-energizing non-thermal particles in clusters.

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Ein Konzept für die Leistungsanalyse von Multi-core Cluster-Computern

PIK - Praxis der Informationsverarbeitung und Kommunikation ◽

10.1515/pik-2014-0012 ◽

2014 ◽

Vol 0 (0) ◽

Author(s):

Heinz Kredel ◽

Hans Günther Kruse ◽

Sabine Richling

Keyword(s):

Core Cluster

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Kynurenines with Neuroactive and Redox Properties: Relevance to Aging and Brain Diseases

Oxidative Medicine and Cellular Longevity ◽

10.1155/2014/646909 ◽

2014 ◽

Vol 2014 ◽

pp. 1-22 ◽

Cited By ~ 43

Author(s):

Jazmin Reyes Ocampo ◽

Rafael Lugo Huitrón ◽

Dinora González-Esquivel ◽

Perla Ugalde-Muñiz ◽

Anabel Jiménez-Anguiano ◽

...

Keyword(s):

Aging Process ◽

Kynurenine Pathway ◽

Experimental Models ◽

Redox Properties ◽

Brain Diseases ◽

Oxygen Species ◽

Neurodegenerative Process ◽

Feedback Cycle ◽

Tryptophan Degradation ◽

Almost All

The kynurenine pathway (KP) is the main route of tryptophan degradation whose final product is NAD+. The metabolism of tryptophan can be altered in ageing and with neurodegenerative process, leading to decreased biosynthesis of nicotinamide. This fact is very relevant considering that tryptophan is the major source of body stores of the nicotinamide-containing NAD+coenzymes, which is involved in almost all the bioenergetic and biosynthetic metabolism. Recently, it has been proposed that endogenous tryptophan and its metabolites can interact and/or produce reactive oxygen species in tissues and cells. This subject is of great importance due to the fact that oxidative stress, alterations in KP metabolites, energetic deficit, cell death, and inflammatory events may converge each other to enter into a feedback cycle where each one depends on the other to exert synergistic actions among them. It is worth mentioning that all these factors have been described in aging and in neurodegenerative processes; however, has so far no one established any direct link between alterations in KP and these factors. In this review, we describe each kynurenine remarking their redox properties, their effects in experimental models, their alterations in the aging process.

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Management of Cardiorenal Metabolic Syndrome in Diabetes Mellitus: A Phytotherapeutic Perspective

Journal of Diabetes Research ◽

10.1155/2014/313718 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Min Kyong Song ◽

Neal M. Davies ◽

Basil D. Roufogalis ◽

Tom Hsun-Wei Huang

Keyword(s):

Complex Disease ◽

Therapeutic Potential ◽

Cardiorenal Syndrome ◽

Current Therapy ◽

Novel Therapies ◽

Development Of Resistance ◽

Feedback Cycle ◽

Large Numbers ◽

Traditional Natural ◽

Natural Medicines

Cardiorenal syndrome (CRS) is a complex disease in which the heart and kidney are simultaneously affected and their deleterious declining functions are reinforced in a feedback cycle, with an accelerated progression. Although the coexistence of kidney and heart failure in the same individual carries an extremely bad prognosis, the exact cause of deterioration and the pathophysiological mechanisms underlying the initiation and maintenance of the interaction are complex, multifactorial in nature, and poorly understood. Current therapy includes diuretics, natriuretic hormones, aquaretics (arginine vasopressin antagonists), vasodilators, and inotropes. However, large numbers of patients still develop intractable disease. Moreover, the development of resistance to many standard therapies, such as diuretics and inotropes, has led to an increasing movement toward utilization and development of novel therapies. Herbal and traditional natural medicines may complement or provide an alternative to prevent or delay the progression of CRS. This review provides an analysis of the possible mechanisms and the therapeutic potential of phytotherapeutic medicines for the amelioration of the progression of CRS.

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Validity Evidence for the Medical Student Core Physical Examination

10.21203/rs.3.rs-699718/v1 ◽

2021 ◽

Author(s):

Todd Guth ◽

Yoon Soo Park ◽

Janice Hanson ◽

Rachel Yudkowsky

Keyword(s):

Medical Students ◽

Clinical Skills ◽

Validity Evidence ◽

Clinical Experiences ◽

Colorado School ◽

The Core ◽

University Of Colorado ◽

School Of Medicine ◽

Core Cluster ◽

Cut Score

Abstract Background The Core Physical Exam (CPE) has been proposed as a set of key physical exam (PE) items for teaching and assessing PE skills in medical students, and as the basis of a Core + Cluster curriculum. Beyond the initial development of the CPE and proposal of the CPE and the Core + Cluster curriculum, no additional validity evidence has been presented for use of the CPE to teach or assess PE skills of medical students. As a result, a modified version of the CPE was developed by faculty at the University of Colorado School of Medicine (UCSOM) and implemented in the school’s clinical skills course in the context of an evolving Core + Cluster curriculum. Methods Validity evidence for the 25-item University of Colorado School of Medicine (UCSOM) CPE was analyzed using longitudinal assessment data from 366 medical students (Classes of 2019 and 2020), obtained from September 2015 through December 2019. Using Messick's unified validity framework, validity evidence specific to content, response process, internal structure, relationship to other variables, and consequences was gathered. Results Content and response process validity evidence included expert content review and rater training. For internal structure, a generalizability study phi coefficient of 0.258 suggests low reliability for a single assessment due to variability in learner performance by occasion and CPE items. Correlations of performance on the UCSOM CPE with other PE assessments were low, ranging from .00-.34. Consequences were explored through determination of a pass-fail cut score. Following a modified Angoff process, clinical skills course directors selected a consensus pass-fail cut score of 80% as a defensible and practical threshold for entry into precepted clinical experiences. Conclusions Validity evidence supports the use of the UCSOM CPE as an instructional strategy for teaching PE skills and as a formative assessment of readiness for precepted clinical experiences. The low generalizability coefficient suggests that inferences about PE skills based on the UCSOM CPE alone should be made with caution, and that the UCSOM CPE in isolation should be used primarily as a formative assessment.

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Academic Freedom, With an Asterisk

Unassailable Ideas ◽

10.1093/oso/9780190078065.003.0005 ◽

2020 ◽

pp. 47-56

Author(s):

Ilana Redstone

Keyword(s):

Social Media ◽

Academic Freedom ◽

Feedback Cycle ◽

Contemporary Technology ◽

Scope Of Protection

Colleges tend to have policies on academic freedom that on their face appear to confer broad protection. But the actual scope of protection is a matter of interpretation, and is often much narrower. In practice, the measure of acceptable campus expression is often based on the extent to which speech offends or is viewed as harmful. The contemporary technology environment amplifies this dynamic. Social media help ensure that expression that is accused of being offensive is communicated to the very people most likely to view it as such, leading to a feedback cycle that further increases the risks that opinions or research conclusions falling outside of campus-proscribed boundaries will attract attention and protest. This is the academic freedom elephant in the room, and it plays a far more powerful role in shaping discourse and research than does the text in a university’s formal academic freedom policy.

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Lexical choices along the creative process of coc comparato

Signum Estudos da Linguagem ◽

10.5433/2237-4876.2019v22n1p141 ◽

2019 ◽

Vol 22 (1) ◽

pp. 141

Author(s):

Livia Sprizão de Oliveira ◽

Edina Regina Panichi

Keyword(s):

Creative Process ◽

Writing Process ◽

Genetic Criticism ◽

Lexical Choice ◽

Feedback Cycle ◽

The Impact

Lexicographical words represent things – physical or abstracts – and are also plenty of expressive shapes, which are socially built. The grammatical use of words disseminates denotative meanings and metaphorical effects that engage emotions. The context in which words are placed creates a feedback cycle between the sign and the psychic images that it evokes. Through the analysis of the manuscripts of the Brazilian dramatist, Doc Comparato, we shall observe the movements of experimentation and lexical choice along the creative process of his writing of the script Jamais (Never) - also called Calabar or A tribute to the treason. We are going to verify the changes on the effects of meaning by comparing the reviews applied to the text, following the author’s search for the grammatical shape that gives life to the idea. In order to analyze the metamorphosis of the writing process we shall use the fundaments of Genetic Criticism and the Stylistic to evaluate the results reached by the author – considering that a dramaturgical text is made to be staged and, for being so, must predict the impact of the sounds of words and also the actions that follow them.

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Association between ALS and retroviruses: evidence from bioinformatics analysis

BMC Bioinformatics ◽

10.1186/s12859-019-3249-8 ◽

2019 ◽

Vol 20 (S24) ◽

Author(s):

Jon P. Klein ◽

Zhifu Sun ◽

Nathan P. Staff

Keyword(s):

Protein Interaction ◽

Drug Targets ◽

Large Scale ◽

Bioinformatics Analysis ◽

Enrichment Analysis ◽

Protein Interaction Networks ◽

Interaction Networks ◽

Pathway Enrichment Analysis ◽

Protein Database ◽

Core Cluster

Abstract Background Emerging evidence suggests retroviruses play a role in the pathophysiology of amyotrophic lateral sclerosis (ALS). Specifically, activation of ancient viral genes embedded in the human genome is theorized to lead to motor neuron degeneration. We explore whether connections exist between ALS and retroviruses through protein interaction networks (PIN) and pathway analysis, and consider the potential roles in drug target discovery. Protein database and pathway/network analytical software including Ingenuity Pathway BioProfiler, STRING, and CytoScape were utilized to identify overlapping protein interaction networks and extract core cluster (s) of retroviruses and ALS. Results Topological and statistical analysis of the ALS-PIN and retrovirus-PIN identified a shared, essential protein network and a core cluster with significant connections with both networks. The identified core cluster has three interleukin molecules IL10, Il-6 and IL-1B, a central apoptosis regulator TP53, and several major transcription regulators including MAPK1, ANXA5, SQSTM1, SREBF2, and FADD. Pathway enrichment analysis showed that this core cluster is associated with the glucocorticoid receptor singling and neuroinflammation signaling pathways. For confirmation purposes, we applied the same methodology to the West Nile and Polio virus, which demonstrated trivial connectivity with ALS, supporting the unique connection between ALS and retroviruses. Conclusions Bioinformatics analysis provides evidence to support pathological links between ALS and retroviral activation. The neuroinflammation and apoptotic regulation pathways are specifically implicated. The continuation and further analysis of large scale genome studies may prove useful in exploring genes important in retroviral activation and ALS, which may help discover new drug targets.

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Output Feedback Assignability for Nonlinear Min-Max Systems

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.374 ◽

2011 ◽

Vol 314-316 ◽

pp. 374-379

Author(s):

Hong Yun Wei ◽

Zhong Xun Zhu ◽

Yue Gang Tao ◽

Wen De Chen

Keyword(s):

Output Feedback ◽

Cycle Time ◽

Closed Loop ◽

Loop System ◽

Closed Loop System ◽

Sufficient Criterion ◽

Feedback Cycle ◽

Necessary And Sufficient ◽

Coloring Graph

This paper investigates the output feedback cycle time assignability of the min-max systems which are more complex than the systems studied in recent years. Max-plus projection representation for the closed-loop system with min-max output feedback is introduced. The coloring graph is presented and applied to analyze the structure of systems effectively. The necessary and sufficient criterion for the output feedback cycle time assignability is established which is an extension of the results studied before. The methods are constructive in nature.

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