24 research outputs found

    Absence of Evidence Is Not Evidence of Absence: The Color-Density Relation at Fixed Stellar Mass Persists to z ~ 1

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    We use data drawn from the DEEP2 Galaxy Redshift Survey to investigate the relationship between local galaxy density, stellar mass, and rest-frame galaxy color. At z ~ 0.9, we find that the shape of the stellar mass function at the high-mass (log (M*/Msun) > 10.1) end depends on the local environment, with high-density regions favoring more massive systems. Accounting for this stellar mass-environment relation (i.e., working at fixed stellar mass), we find a significant color-density relation for galaxies with 10.6 < log(M*/Msun) < 11.1 and 0.75 < z < 0.95. This result is shown to be robust to variations in the sample selection and to extend to even lower masses (down to log(M*/Msun) ~ 10.4). We conclude by discussing our results in comparison to recent works in the literature, which report no significant correlation between galaxy properties and environment at fixed stellar mass for the same redshift and stellar mass domain. The non-detection of environmental dependence found in other data sets is largely attributable to their smaller samples size and lower sampling density, as well as systematic effects such as inaccurate redshifts and biased analysis techniques. Ultimately, our results based on DEEP2 data illustrate that the evolutionary state of a galaxy at z ~ 1 is not exclusively determined by the stellar mass of the galaxy. Instead, we show that local environment appears to play a distinct role in the transformation of galaxy properties at z > 1.Comment: 10 pages, 5 Figures; Accepted for publication in MNRA

    SDSS-IV MaNGA: the spatial distribution of star formation and its dependence on mass, structure, and environment

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    We study the spatially resolved star formation of 1494 galaxies in the SDSS-IV MaNGA Survey. Star formation rates (SFRs) are calculated using a two-step process, using H α in star-forming regions and Dn4000 in regions identified as active galactic nucleus/low-ionization (nuclear) emission region [AGN/LI(N)ER] or lineless. The roles of secular and environmental quenching processes are investigated by studying the dependence of the radial profiles of specific star formation rate on stellar mass, galaxy structure, and environment. We report on the existence of ‘centrally suppressed’ galaxies, which have suppressed Specific Star Formation Rate (SSFR) in their cores compared to their discs. The profiles of centrally suppressed and unsuppressed galaxies are distributed in a bimodal way. Galaxies with high stellar mass and core velocity dispersion are found to be much more likely to be centrally suppressed than low-mass galaxies, and we show that this is related to morphology and the presence of AGN/LI(N)ER like emission. Centrally suppressed galaxies also display lower star formation at all radii compared to unsuppressed galaxies. The profiles of central and satellite galaxies are also compared, and we find that satellite galaxies experience lower specific star formation rates at all radii than central galaxies. This uniform suppression could be a signal of the stripping of hot halo gas in the process known as strangulation. We find that satellites are not more likely to be suppressed in their cores than centrals, indicating that the core suppression is an entirely internal process. We find no correlation between the local environment density and the profiles of star formation rate surface density

    Thermography as a method of acquiring competences in Physiology. Application case for hand blood flow control

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    5 p.The present work proposes a methodological structure as part of the learning of the circulatory system. For this, the application of thermal stress is used, by immersing the hands in cold water to visualize the reperfusion of the hands. Learning, based on the visualization and analysis of thermographic images, allows the acquisition of specific competences at the university level. In graduate studies such as physiotherapy and nursing, the use of virtual tools and materials that allow the acquisition of skills and technical knowledge is essential for the job performance of future professionals. The application of this methodology is proposed in practical sessions of subjects in the area of knowledge of Physiology, to demonstrate and facilitate the understanding of the circulatory system. This approach is framed within the discipline of virtual laboratories since the virtual materials generated can be used for the acquisition of skills and practical competencies, as well as for the evaluation of competencies in e-learning courses. In this way, by recording a pedagogical video that shows a short practice, 5 minutes long, it is possible to establish the necessary knowledge bases to expand them later. This material is easily implementable in any learning management system.S

    One health:past successes and future challenges in three african contexts

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    The recent emergence of zoonotic diseases such as Highly Pathogenic Avian Influenza (HPAI) and Severe Acute Respiratory Syndrome (SARS) have contributed to dominant Global Health narratives around health securitisation and pandemic preparedness, calling for greater co-operation between the health, veterinary and environmental sectors in the ever-evolving One Health movement. A decade later, One Health advocates face increasing pressure to translate the approach from theory into action.A qualitative case study methodology was used to examine the emerging relationships between international One Health dialogue and its practical implementation in the African health policy context. A series of Key Informant Interviews (n = 32) with policy makers, government officials and academics in Nigeria, Tanzania and Uganda are presented as three separate case studies. Each case examines a significant aspect of One Health operationalisation, framed around the control of both emerging and Neglected Zoonotic Diseases including HPAI, Human African Trypanosomiasis and rabies. The research found that while there is general enthusiasm and a strong affirmative argument for adoption of One Health approaches in Africa, identifying alternative contexts away from a narrow focus on pandemics will help broaden its appeal, particularly for national or regionally significant endemic and neglected diseases not usually addressed under a "global" remit.There is no 'one size fits all' approach to achieving the intersectoral collaboration, significant resource mobilisation and political co-operation required to realise a One Health approach. Individual country requirements cannot be underestimated, dismissed or prescribed in a top down manner. This article contributes to the growing discussion regarding not whether One Health should be operationalised, but how this may be achieved

    Franck-Condon blockade in suspended carbon nanotube quantum dots

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    Understanding the influence of vibrational motion of the atoms on electronic transitions in molecules constitutes a cornerstone of quantum physics, as epitomized by the Franck-Condon principle of spectroscopy. Recent advances in building molecular-electronics devices and nanoelectromechanical systems open a new arena for studying the interaction between mechanical and electronic degrees of freedom in transport at the single-molecule level. The tunneling of electrons through molecules or suspended quantum dots has been shown to excite vibrational modes, or vibrons. Beyond this effect, theory predicts that strong electron-vibron coupling dramatically suppresses the current flow at low biases, a collective behaviour known as Franck-Condon blockade. Here we show measurements on quantum dots formed in suspended single-wall carbon nanotubes revealing a remarkably large electron-vibron coupling and, due to the high quality and unprecedented tunability of our samples, admit a quantitative analysis of vibron-mediated electronic transport in the regime of strong electron-vibron coupling. This allows us to unambiguously demonstrate the Franck-Condon blockade in a suspended nanostructure. The large observed electron-vibron coupling could ultimately be a key ingredient for the detection of quantized mechanical motion. It also emphasizes the unique potential for nanoelectromechanical device applications based on suspended graphene sheets and carbon nanotubes.Comment: 7 pages, 3 figure

    Researching online practices

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    This chapter considers what is entailed in researching\ud activities involving use of the internet from the\ud standpoint of people engaging in social practices like\ud blogging, online shopping, participating in online\ud social networks, and being a fanfiction writer or music\ud video creator. It outlines what we mean by 'practices'\ud as a technical concept, and identifies some key\ud implications for research design and methodology of\ud taking a practice approach to researching social\ud phenomena. We pay particular attention to a concept\ud of 'connective inquiry' that disrupts the online/offline\ud distinction and to the idea of 'affinity spaces' as a useful construct for understanding how people become\ud proficient in certain kinds of internet-related\ud practices. The chapter privileges attempts to gain\ud 'insider' understandings of internet-related practices,\ud as experienced from the perspective of the actors\ud themselves (emic), rather than imposing observer\ud meanings upon these practices (etic) from the outside\ud or on the basis of generalizations presumed to hold\ud across a range of cultural contexts. We live in a period\ud of massive technological and institutional change,\ud where new things to be done and new ways of doing\ud things – increasingly on a global scale – are emerging\ud apace, mediated to a large extent by the internet.\ud Internet-related practices are the 'nuts and bolts' of a\ud great deal of the culture and history being made in\ud this conjuncture. Understanding these nuts and bolts,\ud then, is crucial to understanding our times – locally\ud and globally

    Persistent Cardiometabolic Health Gaps: Can Therapeutic Care Gaps Be Precisely Identified from Electronic Health Records

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    The objective of this study was to determine the strengths and limitations of using structured electronic health records (EHR) to identify and manage cardiometabolic (CM) health gaps. We used medication adherence measures derived from dispense data to attribute related therapeutic care gaps (i.e., no action to close health gaps) to patient- (i.e., failure to retrieve medication or low adherence) or clinician-related (i.e., failure to initiate/titrate medication) behavior. We illustrated how such data can be used to manage health and care gaps for blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), and HbA1c for 240,582 Sutter Health primary care patients. Prevalence of health gaps was 44% for patients with hypertension, 33% with hyperlipidemia, and 57% with diabetes. Failure to retrieve medication was common; this patient-related care gap was highly associated with health gaps (odds ratios (OR): 1.23&ndash;1.76). Clinician-related therapeutic care gaps were common (16% for hypertension, and 40% and 27% for hyperlipidemia and diabetes, respectively), and strongly related to health gaps for hyperlipidemia (OR = 5.8; 95% CI: 5.6&ndash;6.0) and diabetes (OR = 5.7; 95% CI: 5.4&ndash;6.0). Additionally, a substantial minority of care gaps (9% to 21%) were uncertain, meaning we lacked evidence to attribute the gap to either patients or clinicians, hindering efforts to close the gaps
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