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Environment-size relation of massive passive galaxies at 0.5 <= z <= 0.8
Get PDFPublished versionWe use the unparalleled statistics of the VIPERS survey to investigate the relation between the surface mean stellar mass density Σ = ℳ/(2 πRe2) of massive passive galaxies (MPGs, ℳ ≥ 1011 M⊙) and their local environment in the redshift range 0.5 ≤ z ≤ 0.8. Passive galaxies were selected on the basis of their NUVrK colors (∼900 objects), and the environment was defined as the galaxy density contrast, δ, using the fifth nearest-neighbor approach. The analysis of Σ versus δ was carried out in two stellar mass bins. In galaxies with ℳ ≤ 2 × 1011 M⊙, no correlation between Σ and δ is observed. This implies that the accretion of satellite galaxies, which is more frequent in denser environments (groups or cluster outskirts) and efficient in reducing the galaxy Σ, is not relevant in the formation and evolution of these systems. Conversely, in galaxies with ℳ > 2 × 1011 M⊙, we find an excess of MPGs with low Σ and a deficit of high-Σ MPGs in the densest regions with respect to other environments. We interpret this result as due to the migration of some high-Σ MPGs (< 1% of the total population of MPGs) into low-Σ MPGs, probably through mergers or cannibalism of small satellites. In summary, our results imply that the accretion of satellite galaxies has a marginal role in the mass-assembly history of most MPGs. We have previously found that the number density of VIPERS massive star-forming galaxies (MSFGs) declines rapidily from z = 0.8 to z = 0.5, which mirrors the rapid increase in the number density of MPGs. This indicates that the MSFGs at z ≥ 0.8 migrate to the MPG population. Here, we investigate the Σ–δ relation of MSFGs at z ≥ 0.8 and find that it is consistent within 1σ with that of low-Σ MPGs at z ≤ 0.8. Thus, the results of this and our previous paper show that MSFGs at z ≥ 0.8 are consistent in terms of number and environment with being the progenitors of low-Σ MPGs at z < 0.8.</p
A dense, solar metallicity ISM in the z=4.2 dusty star-forming galaxy SPT 0418-47
Get PDFPublished versionWe present a study of six far-infrared fine structure lines in the z = 4.225 lensed dusty star-forming galaxy SPT 0418−47 to probe the physical conditions of its interstellar medium (ISM). In particular, we report Atacama Pathfinder EXperiment (APEX) detections of the [OI] 145 μm and [OIII] 88 μm lines and Atacama Compact Array (ACA) detections of the [NII] 122 and 205 μm lines. The [OI] 145 μm/[CII] 158 μm line ratio is ∼5× higher compared to the average of local galaxies. We interpret this as evidence that the ISM is dominated by photo-dissociation regions with high gas densities. The line ratios, and in particular those of [OIII] 88 μm and [NII] 122 μm imply that the ISM in SPT 0418−47 is already chemically enriched to nearly solar metallicity. While the strong gravitational amplification was required to detect these lines with APEX, larger samples can be observed with the Atacama Large Millimeter/submillimeter Array (ALMA), and should allow observers to determine if the dense, solar metallicity ISM is common among these highly star-forming galaxies
Combinations of reproductive, individual, and weather effects best explain torpor patterns among female little brown bats (Myotis lucifugus)
Get PDFPublished versionHeterothermic mammals can use torpor, a state of metabolic suppression, to conserve energy during times of limited food and poor environmental conditions. Females may use torpor throughout gestation and lactation; however, there are associated physiological and ecological costs with potential fitness consequences. Previous studies have controlled for, but not quantified the impact of interindividual variation on torpor patterns and understanding this may provide insight on why certain thermoregulatory responses are employed. The objective of this study was to identify and quantitatively characterize the intrinsic variables and weather conditions that best explain variation in torpor patterns among individual female little brown bats, Myotis lucifugus. We used temperature‐sensitive radio‐transmitters affixed to females to measure skin temperature patterns of 35 individuals roosting in bat boxes in the spring and summer. We used Bayesian multi‐model inference to rank a priori‐selected models and variables based on their explanatory power. Reproductive condition and interindividual effects best explained torpor duration and depth, and weather best explained torpor frequency. Of the reproductive conditions, lactating females used torpor for the shortest durations and at shallower depths (i.e., smallest drop in minimum Tsk), while females in early spring (i.e., not‐obviously‐pregnant) used torpor for the longest and deepest. Among individuals, the greatest difference in effects on duration occurred between pregnant individuals, suggesting interindividual variation within reproductive condition. Increases in precipitation and wind were associated with a higher probability of torpor use. Our results provide further support that multiple variables explain torpor patterns and highlight the importance of including individual effects when studying thermoregulatory patterns in heterothermic species
Values related to professionalism in dental education at the University of Chile: Student and faculty perceptions
Get PDFPublished versionObjective: It is recognized that professionalism should play a central role in dental education. However, its implementation into the curricula of dental schools is still limited. Our objective was to identify the main values related to professionalism based on the perceptions of students and faculty members from the Faculty of Dentistry, University of Chile.Methods: A Dental Values Survey was validated and culturally adapted in order to guarantee the greatest possible internal validity. The adapted survey was administered to students and faculty members (416 and 225, respectively). The final survey contained 64 items rated on a Likert scale of 1‐5. Each item was categorized according to five dimensions: Altruism, Consciousness, Personal Satisfaction, Quality of Life and Professional Status. The values were compared between faculty and students and among students at different courses. A values scale was constructed by selecting the five items with the highest average score for each dimension.Results: Survey respondents composed 34.32% of the universe, of which 50.46%
were faculty and 49.54% were students. Values associated with Altruism, Consciousness and Professional Status, were the highest rated by students and faculty. Values associated with Personal Satisfaction and Quality of Life received the lowest scores for both groups.Conclusions: To provide the best possible attention to patients (Consciousness), and
that patients have access to affordable dental care (Altruism), are the values at the
top of our scale. On the other hand, to maintain financial stability and to be well paid
(Quality of Life) were the less considered
Mineral data (SEM, electron microprobe, Raman spectroscopy) from epithermal hydrothermal alteration of the Miocene Sigri Petrified Forest and host pyroclastic rocks, Western Lesbos, Greece
Get PDFPublished versionData available from a detailed mineralogical investigation of the Petrified Forest of Lesbos and its host pyroclastic rocks [1] are summarized and a link is provided to the full data at https://data.mendeley.com/datasets/dxwfd32zms/1. Samples were taken from petrified wood, fresh and devitrified tuffs, and from epithermal veins and epithermally altered tuffs. Backscattered electron (BSE) images were made by scanning electron microscope (SEM) from polished thin sections of 16 samples to show textural relationships between minerals. Minerals were identified by energy dispersive spectroscopy (EDS). Further chemical analysis by electron microprobe (EMP) were made of trace elements in the petrified wood and of Mn-oxide minerals. Polymorphs of silica were investigated by Raman spectroscopy. SEM X-Ray maps were made of selected sites with manganese oxide minerals. In this contribution, the general character of each analyzed sample is summarized and a brief inventory of available data is presented, with specific reference to features in the on-line data. The significance of these data for the origin of the petrification of the wood and the epithermal veining of the host pyroclastic rocks is provided in “Nature of the hydrothermal alteration of the Miocene Sigri Petrified Forest and host pyroclastic rocks, Lesbos, Greece” [1] https://doi.org/10.1016/j.jvolgeores.2018.11.018. The data will be of comparative value to those investigating petrification of wood, devitrification of tuffs, and epithermal Mn-Fe mineralization in other areas
Cascade Second Order Sliding Mode Control for Permanent Magnet Synchronous Motor Drive
Get PDFPublished versionThis paper presents a cascade second-order sliding mode control scheme applied to a permanent magnet synchronous motor for speed tracking applications. The control system is comprised of two control loops for the speed and the armature current control, where the command of the speed controller (outer loop) is the reference of the q-current controller (inner loop) that forms the cascade structure. The sliding mode control algorithm is based on a single input-output state space model and a second order control structure. The proposed cascade second order sliding mode control approach is validated on an experimental permanent magnet synchronous motor drive. Experimental results are provided to validate the effectiveness of the proposed control strategy with respect to speed and current control. Moreover, the robustness of the second-order sliding mode controller is guaranteed in terms of unknown disturbances and parametric and modeling uncertainties
Dissecting the Genetic Basis of Grain Size and Weight in Barley (Hordeum vulgare L.) by QTL and Comparative Genetic Analyses
Get PDFPublished versionGrain size and weight are crucial components of barley yield and quality and are the target characteristics of domestication and modern breeding. Despite this, little is known about the genetic and molecular mechanisms of grain size and weight in barley. Here, we evaluated nine traits determining grain size and weight, including thousand grain weight (Tgw), grain length (Gl), grain width (Gw), grain length-width ratio (Lwr), grain area (Ga), grain perimeter (Gp), grain diameter (Gd), grain roundness (Gr), and factor form density (Ffd), in a double haploid (DH) population for three consecutive years. Using five mapping methods, we successfully identified 60 reliable QTLs and 27 hotspot regions that distributed on all chromosomes except 6H which controls the nine traits of grain size and weight. Moreover, we also identified 164 barley orthologs of 112 grain size/weight genes from rice, maize, wheat and 38 barley genes that affect grain yield. A total of 45 barley genes or orthologs were identified as potential candidate genes for barley grain size and weight, including 12, 20, 9, and 4 genes or orthologs for barley, rice, maize, and wheat, respectively. Importantly, 20 of them were located in the 14 QTL hotspot regions on chromosome 1H, 2H, 3H, 5H, and 7H, which controls barley grain size and weight. These results indicated that grain size/weight genes of other cereal species might have the same or similar functions in barley. Our findings provide new insights into the understanding of the genetic basis of grain size and weight in barley, and new information to facilitate high-yield breeding in barley. The function of these potential candidate genes identified in this study are worth exploring and studying in detail
Retention following Two-Stage Collaborative Exams Depends on Timing and Student Performance
No full textPublished versionMultistage collaborative exams are implemented to enhance learning and retention of course material. However, the effects of multistage collaborative exams on retention of course content are varied. These discrepancies may be due to a number of factors. To date, studies examining collaborative exams and content retention have used questions that all, or mostly, require students to select an answer, rather than generate one of their own. However, content retention can improve when students generate their own responses. Thus, we examined the effect of collaborative exams with open-ended questions on retention of course content. Retention was measured at two time periods; one relatively shortly (9 days) following a collaborative exam and another over a longer time period (23 days). Furthermore, we examined whether content retention differed for low-, mid-, or high-performing students. Our results suggest that collaborative exams offer retention benefits at relatively long time periods between pre- and post tests, but not over shorter time periods. Retention varied across students in different performance categories. Our study, the first to use only open-ended questions, showed relatively small effects compared with studies using multiple-choice or fill-in-the-blank format, but still suggest that collaborative exams can aid in content retention
Introduction “Cephalopods of state”: Beckett and Biopolitics
Get PDFPublished versionBeckett studies has changed, and changed utterly, in the last twenty years, extending its preoccupation with humanist philosophies to an engagement with history and politics. In the process, the inscrutable aspect of Beckett's views on a range of political subjects has diminished. Emilie Morin's Beckett Political Imagination (2017) provides ample evidence of his engagement with politics, while James McNaughton's Samuel Beckett and the Politics of Aftermath (2018) extends the achievement of earlier accounts of his political aesthetic (e.g. Adorno, Boxall, Jones). One area of scholarship that has proved exceptionally fertile, if that is the right phrase, is biopolitics. Foucault's identification of a new regime of power predicated on the management of populations, as distinct from individuals, is indispensable to an account of Beckett's political bodies, as this volume confirms
2019-03-15 Senate Minutes and Agenda
No full textMinutes and agenda for the March 15th, 2019 meeting of Saint Mary’s University Senate