Effects of Calcium, Strontium, and Magnesium on the Coccolithophorid Cricosphaera (Hymenomonas) carterae. I. Calcification

The present investigation concerns the effects of calcium, strontium, and magnesium on calcification and mineralogy of the calcified bodies (coccoliths) of the coccolithophorid Cricosphaera (Hymenomonas) carterae. The capacity of cells to calcify in various concentrations of these ions was examined following preliminary decalcification in CO2. At a concentration of 10-2 M Ca, 75% of the cells formed coccoliths within 24 h and almost all cells were recalcified after 2 days. At 10-3 or 10-4 M Ca no recalcification occurred. However, with the addition of Sr to the Ca-deficient media, calcification took place as shown by observations of coccoliths and by analysis of Ca. The percentage of calcified cells increased with increasing concentrations of Sr. Strontium added to a Ca-deficient media was much more effective than an equivalent concentration of Ca. No Sr was deposited in the coccoliths. X-ray analysis demonstrated that calcite was deposited by cells in all concentrations of Ca and Sr at which calcification took place. At concentrations of Mg in the media from 0.0 to 4.2×10-2 M, the cells retained their ability to calcify, although calcification was markedly reduced in the absence of Mg. In low Mg concentrations (1.3×10-4 and 4.2×10-6 M), the coccoliths were 60% calcite and 40% aragonite, and in the absence of Mg, only calcite was formed

Anomalous supersolidity in a weakly interacting dipolar Bose mixture on a square lattice

We calculate the mean-field phase diagram of a zero-temperature, binary Bose mixture on a square optical lattice, where one species possesses a non-negligible dipole moment. Remarkably, this system exhibits supersolidity for anomalously weak dipolar interaction strengths, which are readily accessible with current experimental capabilities. The supersolid phases are robust, in that they occupy large regions in the parameter space. Further, we identify a first-order quantum phase transition between supersolid and superfluid phases. Our results demonstrate the rich features of the dipolar Bose mixture, and suggest that this system is well suited for exploring supersolidity in the experimental setting

Potential Mercurian Analogues: Aubrite and Enstatite Chondrite Impact Melt Meteorites

The MESSENGER (MErcury Surface Space ENvironment GEochemistry and Ranging Spacecraft) mission provided new data that have helped us better constrain the surficial mineralogy and composition of Mercury. Mercury has an extremely low oxygen fugacity (f O2) (Iron Wustite (IW) -7.3 to IW -2.6), and at these unique conditions, elements, which usually exhibit lithophile behavior on Earth, can exhibit chalcophile or siderophile behavior on Mercury. No samples have been returned from Mercury; therefore, we must study candidate meteorite analogs to better understand the formation conditions of minerals inferred to be present at the Mercurian surface and Mercurian magmatic processes. In this study, we present a comprehensive analysis of a representative suite of eight aubrites and four enstatite chondrite impact melts (ECIM), which both have a similar f O2 to Mercury, and contain exotic sulfides that have been inferred to be present at the Mercurian surface. These characteristics allow us to assess their relevance for understanding the mineralogy and magmatic processes of Mercury. The ECIM were previously classified as aubrites, but we show that they are actually ECIM with a potential EH (high enstatite) parent body origin due to the presence of niningerite, Si-enriched kamacite, and uniform Ni in schreibersite. We propose that, with respect to the aubrites, the ECIM represent an ideal candidate for Mercurian studies due to their mineralogy and modal mineralogy. Compared to the aubrites, the ECIM samples do not contain forsterite or diopside, show a poorer sulfide diversity, contain graphite, and have a higher volume percentage of metal phases. Although the Mercurian surface contains forsterite and diopside, graphite and a similar amount of metal and sulfides as seen in the ECIM are inferred to be present on Mercury. According to the calculated normative Mercurian mineralogy, both candidate meteorites are most analogous to the Caloris Basin and Northern Plains Lower Mg regions

Unlocking biomarker discovery: Large scale application of aptamer proteomic technology for early detection of lung cancer

Lung cancer is the leading cause of cancer deaths, because ~84% of cases are diagnosed at an advanced stage. Worldwide in 2008, ~1.5 million people were diagnosed and ~1.3 million died – a survival rate unchanged since 1960. However, patients diagnosed at an early stage and have surgery experience an 86% overall 5-year survival. New diagnostics are therefore needed to identify lung cancer at this stage. Here we present the first large scale clinical use of aptamers to discover blood protein biomarkers in disease with our breakthrough proteomic technology. This multi-center case-control study was conducted in archived samples from 1,326 subjects from four independent studies of non-small cell lung cancer (NSCLC) in long-term tobacco-exposed populations. We measured >800 proteins in 15uL of serum, identified 44 candidate biomarkers, and developed a 12-protein panel that distinguished NSCLC from controls with 91% sensitivity and 84% specificity in a training set and 89% sensitivity and 83% specificity in a blinded, independent verification set. Performance was similar for early and late stage NSCLC. This is a significant advance in proteomics in an area of high clinical need

Aubrite and Enstatite Chondrite Impact Melt Meteorites: Analogs to Mercury?

New data obtained during the MESSENGER mission has allowed us to better contrain the composition and mineralogy of the mercurian surface. One unique feature of Mercury is its extremely low oxygen fugacity (O2) (Iron Wustite (IW) -7.3 to IW-2.6). At such extreme conditions, elements that exhibit lithophile behavior on Earth can exhibit chalcophile or siderophile behavior, leading to the formation of exotic sulfides and metals. As no samples have been returned from Mercury, it is critical to study meteorite analogs to better under-stand the formation conditions of the minerals present at the mercurian surface, as well as mercurian magmatic processes. Given the low fO2 on Mercury, we have selected to investigate potential meteoritic analogs for Mercury among the most reduced meteorite types, including the aubrites and enstatite chondrite impact melts. The aubrites are differentiated meteorites that show varying degrees of brecciation, have a similar O2 to the mercurian surface and interior, and contain exotic sulfides that have been inferred to be present on the mercurian surface. The enstatite chondrite impact melts are from undifferentiated parent bodies, have a similar O2 to the mercurian surface and interior, and contain exotic sulfides that have been inferred to be present on the mercurian surface. In this study, we present a comprehensive analysis of a representative suite of aubrites and enstatite chondrite impact melts and assess their relevance to under-standing magmatic processes on Mercury

Investigating the History of Aubrites Using X-Ray Computed Tomography and Bulk Partition Coefficients

The aubrites are a unique group of differentiated meteorites that formed on parent bodies with oxygen fugacities (O2) from ~2 to ~6 log units below the iron-wustite buffer. At these highly reduced condi- tions, elements deviate from the geochemical behavior exhibited at terrestrial O2, and may form FeO-poor silicates, Si-bearing metals, and exotic sulfides. Geochemical examinations of aubrites, such as mineral major-element compositions, bulk-rock compositions, O isotopes, and crystallization ages, are crucial to understand their formation and evolution at extreme O2 conditions. In this study, we determine partitioning relationships of elements between bulk silicate, sulfide, and metal phases within aubrites, and compare the results to partition coefficients determined from petrologic experiments run under mercurian conditions. While previous studies have described the petrology and 2D modal abundances of aubrites, this work provides the first 3D view of aubritic mineralogies, which are com- pared to the available 2D data. Constraints of 3D modal abundances will increase the accuracy of computed bulk distribution coefficients; therefore, 3D scans of aubrite samples are imperative. We utilize X-ray computed tomogra- phy (XCT) to non-destructively analyze the distribution and abundances of mineral phases in aubrites and locate composite clasts of sulfide grains for future analysis

Food Restriction-Induced Changes in Gonadotropin-Inhibiting Hormone Cells are Associated with Changes in Sexual Motivation and Food Hoarding, but not Sexual Performance and Food Intake

We hypothesized that putative anorectic and orexigenic peptides control the motivation to engage in either ingestive or sex behaviors, and these peptides function to optimize reproductive success in environments where energy fluctuates. Here, the putative orexigenic peptide, gonadotropin-inhibiting hormone (GnIH, also known as RFamide-related peptide-3), and the putative anorectic hormones leptin, insulin, and estradiol were examined during the course of food restriction. Groups of female Syrian hamsters were restricted to 75% of their ad libitum food intake or fed ad libitum for 4, 8, or 12 days. Two other groups were food-restricted for 12 days and then re-fed ad libitum for 4 or 8 days. After testing for sex and ingestive behavior, blood was sampled and assayed for peripheral hormones. Brains were immunohistochemically double-labeled for GnIH and the protein product of the immediate early gene, c-fos, a marker of cellular activation. Food hoarding, the number of double-labeled cells, and the percent of GnIH-Ir cells labeled with Fos-Ir were significantly increased at 8 and 12 days after the start of food restriction. Vaginal scent marking and GnIH-Ir cell number significantly decreased after the same duration of restriction. Food hoarding, but not food intake, was significantly positively correlated with cellular activation in GnIH-Ir cells. Vaginal scent marking was significantly negatively correlated with cellular activation in GnIH-Ir cells. There were no significant effects of food restriction on plasma insulin, leptin, estradiol, or progesterone concentrations. In the dorsomedial hypothalamus (DMH) of energetically challenged females, strong projections from NPY-Ir cells were found in close apposition to GnIH-Ir cells. Together these results are consistent with the idea that metabolic signals influence sexual and ingestive motivation via NPY fibers that project to GnIH cells in the DMH

Aubrite and Impact Melt Enstatite Chondrite Meteorites as Potential Analogs to Mercury

The MESSENGER (MErcury Sur-face, Space ENvironment, GEochemistry and Ranging) orbiter measured the Mercurian surface abundances of key rock-forming elements to help us better understand the planet's surface and bulk geochemistry. A major discovery is that the Mercurian surface and interior are characterized by an extremely low oxygen fugacity (O2; Iron-Wstite (IW) -7.3 to IW-2.6. This is supported by low Fe and high S abundances on the surface. This low O2 causes a different elemental partioning from what is observed on Earth. Using surface composition, it was shown that the Mercurian surface mainly consists of normative plagioclase, pyroxene, olivine, and exotic sulfides, such as niningerite ((Mg,Mn, Fe)S) and oldhamite (CaS)