A geochemical study of the Riddle Peaks gabbro, North Cascades: evidence for amphibole accumulation in the mid-crust of an arc

Mid-crustal arc rocks are not commonly exposed, hampering our understanding of magma differentiation processes and mineral crystallization in the mid-crust of arc systems. This thesis presents results of the study of one exposed mid-crustal arc pluton, which is a unique laboratory to understand the geochemical effects of crystallization in this type of system. I report on the major and trace element characteristics of amphibole, plagioclase, and apatite in hornblendite and hornblende gabbro cumulates from the ~44 km2 Riddle Peaks pluton (~77 Ma) in the North Cascades Crystalline Core (NCCC), Washington. Electron microprobe and laser ablation-induced mass spectrometry (LA-ICP-MS), coupled with whole rock major and trace element data, show that the Riddle Peaks contains low Mg# cumulates with 40.7-47.2 wt.% SiO2; Mg# 33-67, where Mg# is defined as 100*[(Mg/(Mg+Fe2+)]. The two rock types present in the pluton are a rhythmically layered gabbro, consisting of hornblendite and hornblende gabbro layered with anorthite to plagioclase-rich gabbro, and a massive hornblende gabbro. The layered gabbro has higher Mg# amphibole (60-70, with the majority 66-70) than massive gabbro (60-63) and more anorthitic plagioclase (layered gabbro = An81-85; massive gabbro = An71-77), suggesting that it was formed by a more primitive liquid. This is supported by modeling that shows that equilibrium liquids from the massive gabbros could have been produced by 40% crystallization of a hornblende gabbro lithology from the parent, calculated liquids in equilibrium with the layered gabbros. Equilibrium liquid calculations also allow for calculation of new apatite partition coefficients for 16 trace elements and REE in a mid-crustal, basaltic andesite system. This study finds that cumulate amphiboles crystallized from a basaltic andesite parent are responsible for increasing La/Yb ratios in derivative melts, such as arc magmas, continental crust and NCCC magmas (NCCC magmas approximated by liquid compositions from the Cardinal Peak and Tenpeak plutons). Amphibole crystallization decreases Dy/Yb in derivative melts; these results are in accordance with predictions from observed arc magmas. Other observed ratios in arc and crustal magmas, such as high Sr/Y (16-20), low Nb/Ta (10-17) and Ti/Zr (30) relative to primitive mantle/chondritic values (Sr/Y = 4.6; Nb/Ta = 18-20; Ti/Zr = 115) are not explained by amphibole crystallization. It has been suggested that amphibole-rich plutons could fractionate certain incompatible trace element pairs to explain the differing ratios in arc magmas and continental crust versus primitive mantle values. With the exception of REE, the Riddle Peaks pluton does not fractionate these ratios sufficiently to explain the differing ratios. If mineral fractionation is occurring, another mineral partitions these elements; or, another process occurs

Implicit Beliefs About Change: A Theory-Grounded Measure Applied to Community Organizations Serving Children, Youth, and Families

The aim of this study was to design and evaluate a theory-grounded measure that taps staff beliefs about the possibility for change in an organization which serves children, youth and families at the community level. The rationale for measuring staff beliefs about change derived from a motivation theory that features two contrasting beliefs structures (entity vs. incremental), and the goals and behavioral dispositions associated with each (Dweck & Leggett, 1988). Twenty-nine individuals associated with the community-based organization completed the newly developed Implicit Beliefs About Change Scale (IBACS) and participatedi n a semi-structured interview. Quantitative analyses indicated that the IBACS has good internal consistency, and yields sufficient response variance. Content analysis of the semi-structured interviews, used to assess the scale\u27s construct validity, uncovered distinctive and theory-consistent behavioral dispositions among those staff members whose beliefs regarding change could be characterized as either incremental or entity in nature. Implications for staff development and future research are discussed

HIV-1 Nef Is Associated with Complex Pulmonary Vascular Lesions in SHIV-nef–infected Macaques

Rationale: HIV-infected patients with pulmonary arterial hypertension have histologic manifestations that are indistinguishable from those found in patients with idiopathic pulmonary arterial hypertension. In addition, the role of pleiotropic viral proteins in the development of plexiform lesions in HIV-related pulmonary hypertension (HRPH) has not been explored. Simian immunodeficiency virus (SIV) infection of macaques has been found to closely recapitulate many of the characteristic features of HIV infection, and thus hallmarks of pulmonary arterial hypertension should also be found in this nonhuman primate model of HIV

Efficacy of a new technique - INtubate-RECruit-SURfactant-Extubate - "IN-REC-SUR-E" - in preterm neonates with respiratory distress syndrome: study protocol for a randomized controlled trial.

BACKGROUND: Although beneficial in clinical practice, the INtubate-SURfactant-Extubate (IN-SUR-E) method is not successful in all preterm neonates with respiratory distress syndrome, with a reported failure rate ranging from 19 to 69 %. One of the possible mechanisms responsible for the unsuccessful IN-SUR-E method, requiring subsequent re-intubation and mechanical ventilation, is the inability of the preterm lung to achieve and maintain an "optimal" functional residual capacity. The importance of lung recruitment before surfactant administration has been demonstrated in animal studies showing that recruitment leads to a more homogeneous surfactant distribution within the lungs. Therefore, the aim of this study is to compare the application of a recruitment maneuver using the high-frequency oscillatory ventilation (HFOV) modality just before the surfactant administration followed by rapid extubation (INtubate-RECruit-SURfactant-Extubate: IN-REC-SUR-E) with IN-SUR-E alone in spontaneously breathing preterm infants requiring nasal continuous positive airway pressure (nCPAP) as initial respiratory support and reaching pre-defined CPAP failure criteria. METHODS/DESIGN: In this study, 206 spontaneously breathing infants born at 24(+0)-27(+6) weeks' gestation and failing nCPAP during the first 24 h of life, will be randomized to receive an HFOV recruitment maneuver (IN-REC-SUR-E) or no recruitment maneuver (IN-SUR-E) just prior to surfactant administration followed by prompt extubation. The primary outcome is the need for mechanical ventilation within the first 3 days of life. Infants in both groups will be considered to have reached the primary outcome when they are not extubated within 30 min after surfactant administration or when they meet the nCPAP failure criteria after extubation. DISCUSSION: From all available data no definitive evidence exists about a positive effect of recruitment before surfactant instillation, but a rationale exists for testing the following hypothesis: a lung recruitment maneuver performed with a step-by-step Continuous Distending Pressure increase during High-Frequency Oscillatory Ventilation (and not with a sustained inflation) could have a positive effects in terms of improved surfactant distribution and consequent its major efficacy in preterm newborns with respiratory distress syndrome. This represents our challenge. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02482766 . Registered on 1 June 2015

Terrestrial and Freshwater Ecosystems and Their Services

Chapter 2, building on prior assessments, provides a global assessment of the observed impacts and projected risks of climate change to terrestrial and freshwater ecosystems, including their component species and the services they provide to people. Where possible, differences among regions, taxonomic groups and ecosystem types are presented. Adaptation options to reduce risks to ecosystems and people are assessed

The DESI Experiment Part II: Instrument Design

DESI (Dark Energy Spectropic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. The DESI instrument is a robotically-actuated, fiber-fed spectrograph capable of taking up to 5,000 simultaneous spectra over a wavelength range from 360 nm to 980 nm. The fibers feed ten three-arm spectrographs with resolution $R= \lambda/\Delta\lambda$ between 2000 and 5500, depending on wavelength. The DESI instrument will be used to conduct a five-year survey designed to cover 14,000 deg$^2$. This powerful instrument will be installed at prime focus on the 4-m Mayall telescope in Kitt Peak, Arizona, along with a new optical corrector, which will provide a three-degree diameter field of view. The DESI collaboration will also deliver a spectroscopic pipeline and data management system to reduce and archive all data for eventual public use

The DESI Experiment Part II: Instrument Design

DESI (Dark Energy Spectropic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. The DESI instrument is a robotically-actuated, fiber-fed spectrograph capable of taking up to 5,000 simultaneous spectra over a wavelength range from 360 nm to 980 nm. The fibers feed ten three-arm spectrographs with resolution $R= \lambda/\Delta\lambda$ between 2000 and 5500, depending on wavelength. The DESI instrument will be used to conduct a five-year survey designed to cover 14,000 deg$^2$. This powerful instrument will be installed at prime focus on the 4-m Mayall telescope in Kitt Peak, Arizona, along with a new optical corrector, which will provide a three-degree diameter field of view. The DESI collaboration will also deliver a spectroscopic pipeline and data management system to reduce and archive all data for eventual public use

The DESI Experiment Part I: Science,Targeting, and Survey Design

DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. To trace the underlying dark matter distribution, spectroscopic targets will be selected in four classes from imaging data. We will measure luminous red galaxies up to $z=1.0$. To probe the Universe out to even higher redshift, DESI will target bright [O II] emission line galaxies up to $z=1.7$. Quasars will be targeted both as direct tracers of the underlying dark matter distribution and, at higher redshifts ( 2.1 < z < 3.5), for the Ly-$\alpha$ forest absorption features in their spectra, which will be used to trace the distribution of neutral hydrogen. When moonlight prevents efficient observations of the faint targets of the baseline survey, DESI will conduct a magnitude-limited Bright Galaxy Survey comprising approximately 10 million galaxies with a median $z\approx 0.2$. In total, more than 30 million galaxy and quasar redshifts will be obtained to measure the BAO feature and determine the matter power spectrum, including redshift space distortions