A physically motivated and empirically calibrated method to measure effective temperature, metallicity, and Ti abundance of M dwarfs

The ability to perform detailed chemical analysis of Sun-like F-, G-, and K-type stars is a powerful tool with many applications including studying the chemical evolution of the Galaxy and constraining planet formation theories. Unfortunately, complications in modeling cooler stellar atmospheres hinders similar analysis of M-dwarf stars. Empirically-calibrated methods to measure M dwarf metallicity from moderate-resolution spectra are currently limited to measuring overall metallicity and rely on astrophysical abundance correlations in stellar populations. We present a new, empirical calibration of synthetic M dwarf spectra that can be used to infer effective temperature, Fe abundance, and Ti abundance. We obtained high-resolution (R~25,000), Y-band (~1 micron) spectra of 29 M dwarfs with NIRSPEC on Keck II. Using the PHOENIX stellar atmosphere modeling code (version 15.5), we generated a grid of synthetic spectra covering a range of temperatures, metallicities, and alpha-enhancements. From our observed and synthetic spectra, we measured the equivalent widths of multiple Fe I and Ti I lines and a temperature-sensitive index based on the FeH bandhead. We used abundances measured from widely-separated solar-type companions to empirically calibrate transformations to the observed indices and equivalent widths that force agreement with the models. Our calibration achieves precisions in Teff, [Fe/H], and [Ti/Fe] of 60 K, 0.1 dex, and 0.05 dex, respectively and is calibrated for 3200 K < Teff < 4100 K, -0.7 < [Fe/H] < +0.3, and -0.05 < [Ti/Fe] < +0.3. This work is a step toward detailed chemical analysis of M dwarfs at a similar precision achieved for FGK stars.Comment: accepted for publication in ApJ, all synthetic spectra available at http://people.bu.edu/mveyette/phoenix

Models of the distribution of 210Pb in a section across the North Equatorial Atlantic Ocean

The deficiency of 210Pb relative to 226Ra in the world\u27s deep ocean is well documented, and the overall residence time of 210Pb bas been calculated to be about 15-100 years. It has been assumed, generally, that the removal mechanism is one of in situ adsorption on settling particles, but Bacon et al. (1976) suggested that a boundary scavenging process with diffusive and advective fluxes of 210Pb from the interior ocean may be a significant factor...

Electric Blower Based Portable Emergency Ventilator

During CPR the victim will most likely be ventilated by a bag-valve-mask. We propose to replace the traditional bag-valvemask with an electric blower ventilator. This handheld feedback controlled device will automatically compensate for mask leak and enable the rescuer to deliver computer controlled respiratory rates and tidal volumes. We will build a working prototype and conduct bench testing to verify that the blower delivers the desired tidal volumes, even with constantly changing leak conditions that exist when a mask that is poorly fit to a victim’s face. In a volunteer study we will observe how typical rescuers use the blower ventilator so we can develop a product that can be easily and correctly used by naïve rescuers. We will conduct human trials in the operating room to demonstrate the safety and efficacy of the blower ventilator

Sediment trap experiments in the deep North Atlantic: Isotopic and elemental fluxes

We have carried out sediment trap experiments at sites in the Sargasso Sea (S2) and in the Atlantic off Barbados (E) to determine the mass flux and chemical composition of material sinking to the sea floor…

College of Liberal Arts and Sciences_COVID-19 Course Content

List of COVID-19 related course content in the University of Maine\u27s College of Liberal Arts and Sciences during the 2020 Spring Semester. Includes descriptions from: Kristin Vekasi, Associate Professor, Political Science for POS 349: Politics of Media and Censorship; Frederic Rondeau, Associate Professor, Modern Languages and Classics for Introduction to French Classics Novels of the XX-XXI century; Marcella Sorg (Research Professor, Department of Anthropology, Climate Change Institute, and Margaret Chase Smith Policy Center for ANT 260: Forensic Anthropology; Derek Michaud, Lecturer, Philosophy; Coordinator of Religious Studies and Judaic Studies for PHI 105: Introduction to Religious Studies and PHI 100: Contemporary Moral Problems; Ayesha Maliwal, Lecturer, Mathematics and Statistics for MAT 116: Introduction to Calculus; Kirsten Jacobson, Chair, Philosophy for PHI 104: Existentialism and Literature and PHI 431: Advanced Topics in the Philosophy of Art; Liliana Herakova, Lecturer, Communication and Journalism for CMJ420 SL: Health Communication; Mark Brewer for POS 348: The Politics of Sport

Vu Villa Staircase Structural Repair

The Vu Villa in uptown Butte has a staircase leading to the second floor that is beginning to sag and needs structural support to fix the sag in the stairs

Impact of Menstrual Cycle on Resting and Postprandial Metabolism in Recreationally Active, Eumenorrheic Females

Changes in estrogen and progesterone across the menstrual cycle impact many biological systems including resting and postprandial metabolism. PURPOSE: To investigate whether menstrual cycle phase impacted resting and postprandial energy expenditure (EE) and substrate utilization in recreationally active, eumenorrheic females. METHODS: In this study, 8 eumenorrheic females (mean±SD age: 33±8 years, BMI: 22.5±2.2 kg/m2; VO2max: 36.9±3.8 ml/kg/min) had resting energy expenditure (REE) and substrate utilization continuously measured with indirect calorimetry for 45 min at rest after an overnight fast, and for 3 h after a mixed meal (490 kcal, 53% carbohydrate, 31% fat, 20% protein) during three distinct phases of the menstrual cycle (early follicular, late follicular, and mid luteal). Menstrual cycle phase was determined using calendar-based counting, ovulation test strips, and confirmed via serum hormone levels (estrogen and progesterone). REE (kcal/day) was calculated using the abbreviated Weir Equation. Diet-induced thermogenesis (DIT) was calculated by subtracting REE (kcal/min) from postprandial EE (kcal/min). This value (kcal/min) was then multiplied by the testing time (180 min) to obtain DIT (kcal) for the 3-h postprandial period. A one-way, repeated measures ANOVA was used to assess differences in REE, respiratory quotient (RQ), and DIT across menstrual cycle phase. All data reported as mean±SD. RESULTS: REE was higher during mid luteal (1486±178 kcal/day) compared to early follicular (1409±108 kcal/day) and late follicular (1390±103 kcal/day) phases (F[2,14]=2.28, p=0.14; effect size=0.25). Resting RQ did not differ across menstrual cycle phase. DIT was higher during early follicular (34±8 kcal) and late follicular (32±12 kcal) than mid-luteal (23±12 kcal) phase (F[2,14]=3.02, p=0.08; effect size=0.30). Postprandial RQ was higher during early follicular (0.87±0.04) and late follicular (0.87±0.03) than mid-luteal (0.85±0.04) phase (F[2,14]=3.22, p=0.07; effect size=0.32). CONCLUSION: These preliminary results on 8 recreationally active, eumenorrheic females suggest that resting and postprandial metabolism may differ across the menstrual cycle. It is unclear whether the magnitude of these differences is clinically meaningful

Replicative Age Induces Mitotic Recombination in the Ribosomal RNA Gene Cluster of Saccharomyces cerevisiae

Somatic mutations contribute to the development of age-associated disease. In earlier work, we found that, at high frequency, aging Saccharomyces cerevisiae diploid cells produce daughters without mitochondrial DNA, leading to loss of respiration competence and increased loss of heterozygosity (LOH) in the nuclear genome. Here we used the recently developed Mother Enrichment Program to ask whether aging cells that maintain the ability to produce respiration-competent daughters also experience increased genomic instability. We discovered that this population exhibits a distinct genomic instability phenotype that primarily affects the repeated ribosomal RNA gene array (rDNA array). As diploid cells passed their median replicative life span, recombination rates between rDNA arrays on homologous chromosomes progressively increased, resulting in mutational events that generated LOH at >300 contiguous open reading frames on the right arm of chromosome XII. We show that, while these recombination events were dependent on the replication fork block protein Fob1, the aging process that underlies this phenotype is Fob1-independent. Furthermore, we provide evidence that this aging process is not driven by mechanisms that modulate rDNA recombination in young cells, including loss of cohesion within the rDNA array or loss of Sir2 function. Instead, we suggest that the age-associated increase in rDNA recombination is a response to increasing DNA replication stress generated in aging cells

Hidden in the Middle : Culture, Value and Reward in Bioinformatics

Bioinformatics - the so-called shotgun marriage between biology and computer science - is an interdiscipline. Despite interdisciplinarity being seen as a virtue, for having the capacity to solve complex problems and foster innovation, it has the potential to place projects and people in anomalous categories. For example, valorised 'outputs' in academia are often defined and rewarded by discipline. Bioinformatics, as an interdisciplinary bricolage, incorporates experts from various disciplinary cultures with their own distinct ways of working. Perceived problems of interdisciplinarity include difficulties of making explicit knowledge that is practical, theoretical, or cognitive. But successful interdisciplinary research also depends on an understanding of disciplinary cultures and value systems, often only tacitly understood by members of the communities in question. In bioinformatics, the 'parent' disciplines have different value systems; for example, what is considered worthwhile research by computer scientists can be thought of as trivial by biologists, and vice versa. This paper concentrates on the problems of reward and recognition described by scientists working in academic bioinformatics in the United Kingdom. We highlight problems that are a consequence of its cross-cultural make-up, recognising that the mismatches in knowledge in this borderland take place not just at the level of the practical, theoretical, or epistemological, but also at the cultural level too. The trend in big, interdisciplinary science is towards multiple authors on a single paper; in bioinformatics this has created hybrid or fractional scientists who find they are being positioned not just in-between established disciplines but also in-between as middle authors or, worse still, left off papers altogether