314 research outputs found
Measures that can be used to teach critical thinking skills in nurse prescribers
Critical thinking is a pervasive skill that involves scrutinizing, differentiating, and appraising information and reflecting on the information gained in order to make judgements and inform clinical decisions. Studies inform us of the need for agreement on the approaches used to teach and measure critical thinking. Nurse prescribers undertake an advanced role that encompass the need to be able to make clinically based decisions about the appropriateness of a specific medication. This requires critical thinking attributes. A variety of teaching and learning approaches are offered which can be used by nurse educators to develop critical thinking skills in nurse prescribers
Discovery of A New Retrograde Trans-Neptunian Object: Hint of A Common Orbital Plane for Low Semi-Major Axis, High Inclination TNOs and Centaurs
Although the majority of Centaurs are thought to have originated in the
scattered disk, with the high-inclination members coming from the Oort cloud,
the origin of the high inclination component of trans-Neptunian objects (TNOs)
remains uncertain. We report the discovery of a retrograde TNO, which we
nickname "Niku", detected by the Pan-STARRS 1 Outer Solar System Survey. Our
numerical integrations show that the orbital dynamics of Niku are very similar
to that of 2008 KV (Drac), with a half-life of Myr. Comparing
similar high inclination TNOs and Centaurs ( AU, ), we find that these objects exhibit a surprising clustering of
ascending node, and occupy a common orbital plane. This orbital configuration
has high statistical significance: 3.8-. An unknown mechanism is
required to explain the observed clustering. This discovery may provide a
pathway to investigate a possible reservoir of high-inclination objects.Comment: 18 pages, 4 figures, 1 table, accepted for publication in ApJ Letter
The Pan-STARRS 1 discoveries of five new neptune trojans
In this work we report the detection of seven Neptune Trojans (NTs) in the
Pan-STARRS 1 (PS1) survey. Five of these are new discoveries, consisting of
four L4 Trojans and one L5 Trojan. Our orbital simulations show that the L5
Trojan stably librates for only several million years. This suggests that the
L5 Trojan must be of recent capture origin. On the other hand, all four new L4
Trojans stably occupy the 1:1 resonance with Neptune for more than 1 Gyr. They
can, therefore, be of primordial origin. Our survey simulation results show
that the inclination width of the Neptune Trojan population should be between
and at 95% confidence, and most likely . In this paper, we describe the PS1 survey, the Outer Solar System
pipeline, the confirming observations, and the orbital/physical properties of
the new Neptune Trojans.Comment: 24 pages, 6 figures, AJ accepte
Limited contribution of permafrost carbon to methane release from thawing peatlands
Models predict that thaw of permafrost soils at northern high-latitudes will release tens of billions of tonnes of carbon (C) to the atmosphere by 21001-3. The effect on the Earth's climate depends strongly on the proportion of this C which is released as the more powerful greenhouse gas methane (CH4), rather than carbon dioxide (CO2)1,4; even if CH4 emissions represent just 2% of the C release, they would contribute approximately one quarter of the climate forcing5. In northern peatlands, thaw of ice-rich permafrost causes surface subsidence (thermokarst) and water-logging6, exposing substantial stores (10s of kg C m-2, ref. 7) of previously-frozen organic matter to anaerobic conditions, and generating ideal conditions for permafrost-derived CH4 release. Here we show that, contrary to expectations, although substantial CH4 fluxes (>20 g CH4 m 2 yr-1) were recorded from thawing peatlands in northern Canada, only a small amount was derived from previously-frozen C (<2 g CH4 m-2 yr-1). Instead, fluxes were driven by anaerobic decomposition of recent C inputs. We conclude that thaw-induced changes in surface wetness and wetland area, rather than the anaerobic decomposition of previously-frozen C, may determine the effect of permafrost thaw on CH4 emissions from northern peatlands
OSSOS. IV. DISCOVERY OF A DWARF PLANET CANDIDATE IN THE 9 : 2 RESONANCE WITH NEPTUNE
We report the discovery and orbit of a new dwarf planet candidate, 2015 RR245, by the Outer Solar System Origins Survey (OSSOS). The orbit of 2015 RR245 is eccentric (e = 0.586), with a semimajor axis near 82 au, yielding a perihelion distance of 34 au. 2015 RR245 has g - r = 0.59 +/- 0.11 and absolute magnitude H-r = 3.6 +/- 0.1; for an assumed albedo of p(V) = 12%, the object has a diameter of similar to 670. km. Based on astrometric measurements from OSSOS and Pan-STARRS1, we find that 2015 RR245 is securely trapped on ten-megayear timescales in the 9: 2 mean-motion resonance with Neptune. It is the first trans-Neptunian object (TNO) identified in this resonance. On hundred-megayear. timescales, particles in 2015 RR245-like orbits depart and sometimes return to the resonance, indicating that 2015 RR245 likely forms part of the long-lived metastable population of distant TNOs that drift between resonance sticking and actively scattering via gravitational encounters with Neptune. The discovery of a 9: 2 TNO stresses the role of resonances in the long-term evolution of objects in the scattering disk. and reinforces the view that distant resonances are heavily populated in the current solar system. This object further motivates detailed modeling of the transient sticking population.Peer reviewe
Essential versus accessory aspects of cell death: recommendations of the NCCD 2015
Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is generally referred to as ‘accidental cell death’ (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. ‘Regulated cell death’ (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death
The International Human Epigenome Consortium: A Blueprint for Scientific Collaboration and Discovery
The International Human Epigenome Consortium (IHEC) coordinates the generation of a catalog of high-resolution reference epigenomes of major primary human cell types. The studies now presented (see the Cell Press IHEC web portal at http://www.cell.com/consortium/IHEC) highlight the coordinated achievements of IHEC teams to gather and interpret comprehensive epigenomic datasets to gain insights in the epigenetic control of cell states relevant for human health and disease
Ecological commonalities among pelagic fishes: comparison of freshwater ciscoes and marine herring and sprat
Systematic comparisons of the ecology between functionally similar fish species from freshwater and marine aquatic systems are surprisingly rare. Here, we discuss commonalities and differences in evolutionary history, population genetics, reproduction and life history, ecological interactions, behavioural ecology and physiological ecology of temperate and Arctic freshwater coregonids (vendace and ciscoes, Coregonus spp.) and marine clupeids (herring, Clupea harengus, and sprat, Sprattus sprattus). We further elucidate potential effects of climate warming on these groups of fish based on the ecological features of coregonids and clupeids documented in the previous parts of the review. These freshwater and marine fishes share a surprisingly high number of similarities. Both groups are relatively short-lived, pelagic planktivorous fishes. The genetic differentiation of local populations is weak and seems to be in part correlated to an astonishing variability of spawning times. The discrete thermal window of each species influences habitat use, diel vertical migrations and supposedly also life history variations. Complex life cycles and preference for cool or cold water make all species vulnerable to the effects of global warming. It is suggested that future research on the functional interdependence between spawning time, life history characteristics, thermal windows and genetic differentiation may profit from a systematic comparison of the patterns found in either coregonids or clupeids
The Outer Solar System Origins Survey : I. Design and First-Quarter Discoveries
We report the discovery, tracking, and detection circumstances for 85 trans-Neptunian objects (TNOs) from the first 42 deg(2) of the Outer Solar System Origins Survey. This ongoing r-band solar system survey uses the 0.9 deg(2) field of view MegaPrime camera on the 3.6m Canada-France-Hawaii Telescope. Our orbital elements for these TNOs are precise to a fractional semimajor axis uncertaintyPeer reviewe
Loneliness of Older Immigrant Groups in Canada: Effects of Ethnic-Cultural Background
This study aimed to explore the loneliness of several groups of older immigrants in Canadacompared to native-born older adults. Data from the Canadian General Social Survey, Cycle 22 (Nolder adults = 3,692) were used. The dependent variable is the 6 item De Jong Gierveld lonelinessscale. Determinants of loneliness included country of birth, ethnic background (cultural context);belongingness (community context) and social networks (social context). Results showed that onlysome immigrant groups are significantly lonelier than older adults born in Canada. Immigrants withsimilar language and culture are not lonelier; while those from countries that differ in nativelanguage/culture are significantly higher on loneliness. Multivariate analyses showed the importanceof cultural background, of composition of the network of relatives and friends, and of localparticipation and feelings of belonging to the Canadian society in explaining loneliness of olderimmigrants
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