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Fossil coral skeletons that retain their original aragonitic mineralogy are generally considered diagenetically unaltered and reliable paleoenvironmental archives. We investigated whether oxygen isotope exchange can occur between these skeletons and ambient sediment pore water without aragonite-to-calcite transformation, focusing on the role of skeletal microstructure in this process. Simulated diagenesis experiments using modern coral skeletons immersed in 18 O-enriched artificial seawater revealed that microstructural complexity – specifically, the phylogenetically controlled arrangement of rapid accretion and thickening deposits – strongly influences isotopic exchange. Organic-rich regions within the skeleton facilitate water penetration, leading to heterogeneous isotopic alteration correlated with skeletal architecture. This provides a mechanism to modify primary isotopic compositions without obvious signs of diagenetic alteration, challenging the assumption that a preserved carbonate polymorph ensures isotopic fidelity in paleoenvironmental reconstructions and complicating the interpretation of the oxygen isotope paleo-temperature proxy in fossil aragonitic biocarbonates. However, we also observed that coral skeletons with less ultrastructural complexity exhibited lower susceptibility to isotope exchange, suggesting a criterium to identify the fossil specimens most suitable for paleoenvironmental analysis.

Oxygen isotope compositions of fossil foraminifera tests are commonly used proxies for ocean paleotemperatures, with reconstructions spanning the last 112 million years. However, the isotopic composition of these calcitic tests can be substantially altered during diagenesis without discernible textural changes. Here, we investigate fluid-mediated isotopic exchange in pristine tests of three modern benthic foraminifera species ( Ammonia sp ., Haynesina germanica , and Amphistegina lessonii ) following immersion into an 18 O-enriched artificial seawater at 90 °C for hours to days. Reacted tests remain texturally pristine but their bulk oxygen isotope compositions reveal rapid and species-dependent isotopic exchange with the water. NanoSIMS imaging reveals the 3-dimensional intra-test distributions of 18 O-enrichment that correlates with test ultra-structure and associated organic matter. Image analysis is used to quantify species level differences in test ultrastructure, which explains the observed species-dependent rates of isotopic exchange. Consequently, even tests considered texturally pristine for paleo-climatic reconstruction purposes may have experienced substantial isotopic exchange; critical paleo-temperature record re-examination is warranted. Paleoclimate reconstructions commonly use oxygen isotope compositions from fossil foraminifera tests as proxies. Here, the authors show that these tests exchange O-isotopes with surrounding fluids, with implications for paleotemperature records.

Fossilized remains of marine calcifiers constitute the physical basis for reconstructions of both deep ocean and sea-surface temperatures going back millions of years, but paleoclimate records derived from their isotope and trace-element chemistry can be biased by diagenesis. Experiments simulating diagenesis in the presence of an 18 O-rich seawater analogue were conducted with modern and 14 Myr old foraminifera ( Ammonia sp.) tests to investigate their relative susceptibility to oxygen isotope exchange. The fossilized tests were of exceptional preservation and similar to modern tests in terms of structure and crystalline organization, but had experienced partial loss of embedded organic structures, thus a priori offering fewer preferential pathways for porewaters to penetrate the tests. NanoSIMS imaging revealed that oxygen isotope exchange was pervasive in fossil tests, with isotopic exchange occurring at approximately half the rate of modern tests. The results unequivocally show that fossil biocalcites are metastable and remain more susceptible to isotope exchange than abiotic calcites millions of years after sedimentation and burial.

Kuzmits, FE and Adams, AJ. The NFL combinedoes it predict performance in the National Football League? J Strength Cond Res 22(6)1721-1727, 2008-The authors investigate the correlation between National Football League (NFL) combine test results and NFL success for players drafted at three different offensive positions (quarterback, running back, and wide receiver) during a recent 6-year period, 1999-2004. The combine consists of series of drills, exercises, interviews, aptitude tests, and physical exams designed to assess the skills of promising college football players and to predict their performance in the NFL. Combine measures examined in this study include 10-, 20-, and 40-yard dashes, bench press, vertical jump, broad jump, 20- and 60-yard shuttles, three-cone drill, and the Wonderlic Personnel Test. Performance criteria include 10 variablesdraft order; 3 years each of salary received and games played; and position-specific data. Using correlation analysis, we find no consistent statistical relationship between combine tests and professional football performance, with the notable exception of sprint tests for running backs. We put forth possible explanations for the general lack of statistical relations detected, and, consequently, we question the overall usefulness of the combine. We also offer suggestions for improving the prediction of success in the NFL, primarily the use of more rigorous psychological tests and the examination of collegiate performance as a job sample test. Finally, from a practical standpoint, the results of the study should encourage NFL team personnel to reevaluate the usefulness of the combineʼs physical tests and exercises as predictors of player performance. This study should encourage team personnel to consider the weighting and importance of various combine measures and the potential benefits of overhauling the combine process, with the goal of creating a more valid system for predicting player success.

The oxygen isotopic compositions of fossil foraminifera tests constitute a continuous proxy record of deep-ocean and sea-surface temperatures spanning the last 120 million years. Here, by incubating foraminifera tests in 18 O-enriched artificial seawater analogues, we demonstrate that the oxygen isotopic composition of optically translucent, i.e., glassy, fossil foraminifera calcite tests can be measurably altered at low temperatures through rapid oxygen grain-boundary diffusion without any visible ultrastructural changes. Oxygen grain boundary diffusion occurs sufficiently fast in foraminifera tests that, under normal upper oceanic sediment conditions, their grain boundaries will be in oxygen isotopic equilibrium with the surrounding pore fluids on a time scale of <100 years, resulting in a notable but correctable bias of the paleotemperature record. When applied to paleotemperatures from 38,400 foraminifera tests used in paleoclimate reconstructions, grain boundary diffusion can be shown to bias prior paleotemperature estimates by as much as +0.86 to −0.46 °C. The process is general and grain boundary diffusion corrections can be applied to other polycrystalline biocarbonates composed of small nanocrystallites (<100 nm), such as those produced by corals, brachiopods, belemnites, and molluscs, the fossils of which are all highly susceptible to the effects of grain boundary diffusion.

This book is designed to consolidate the relevant literature as well as the thoughts of professionals currently working in the field into a practical and accessible reference for the emergency medical technician, student, nurse, resident, and attending emergency physician. Each chapter is divided into four sections: case presentation, discussion, review of the current literature, and recommendations. Designed to serve simultaneously as a learning and reference tool, each chapter begins with a real case that was encountered in an ED setting. The case presentation is followed by a short discussion of the case, as if at a morbidity and mortality conference, by a panel of experienced attending physicians explaining how they would approach the ethical dilemmas associated with the case, and a review of the existing literature.

This research examines the relationships among the types of self-serving political messages sent in organizations, the channels through which they are sent, and the targets to whom they are sent. Two theoretical streams converge in this study: Communication as Political Behavior and Media Usage Theory. A review and synthesis of these two bodies of literature yielded three hypotheses, each of which received strong statistical support. The data suggest that the process of encoding and transmitting self-serving messages is strongly related to the specific target to whom they are sent (boss, subordinate, or peer) and the channel through which they are sent (face-to-face, telephone, memo, or e-mail).

Intracerebral hemorrhage (ICH) remains the second-most common form of stroke with high morbidity and mortality. ICH can be divided into two pathophysiological stages: an acute primary phase, including hematoma volume expansion, and a subacute secondary phase consisting of blood-brain barrier disruption and perihematomal edema expansion. To date, all major trials for ICH have targeted the primary phase with therapies designed to reduce hematoma expansion through blood pressure control, surgical evacuation, and hemostasis. However, none of these trials has resulted in improved clinical outcomes. Magnesium is a ubiquitous element that also plays roles in vasodilation, hemostasis, and blood-brain barrier preservation. Animal models have highlighted potential therapeutic roles for magnesium in neurological diseases specifically targeting these pathophysiological mechanisms. Retrospective studies have also demonstrated inverse associations between admission magnesium levels and hematoma volume, hematoma expansion, and clinical outcome in patients with ICH. These associations, coupled with the multifactorial role of magnesium that targets both primary and secondary phases of ICH, suggest that magnesium may be a viable target of study in future ICH studies.

Purpose The aim of this work was to develop a CAIX-specific nanobody conjugated to IRDye800CW for molecular imaging of pre-invasive breast cancer. Procedures CAIX-specific nanobodies were selected using a modified phage display technology, conjugated site-specifically to IRDye800CW and evaluated in a xenograft breast cancer mouse model using ductal carcinoma in situ cells (DCIS). Results Specific anti-CAIX nanobodies were obtained. Administration of a CAIX-specific nanobody into mice with DCIS xenografts overexpressing CAIX showed after 2 h a mean tumor-to-normal tissue ratio (TNR) of 4.3 ± 0.6, compared to a TNR of 1.4 ± 0.2 in mice injected with the negative control nanobody R2-IR. In DCIS mice, a TNR of 1.8 ± 0.1 was obtained. Biodistribution studies demonstrated an uptake of 14.0 ± 1.1 %I.D./g in DCIS + CAIX tumors, 4.6 ± 0.8 %I.D./g in DCIS tumors, while 2.0 ± 0.2 %I.D./g was obtained with R2-IR. Conclusions These results demonstrate the successful generation of a CAIX-specific nanobody-IRDye800CW conjugate that can be used for rapid imaging of (pre-)invasive breast cancer.