The Role of Copper in Hemoglobin Regeneration

During the past few years a considerable amount of investigation has been devoted to the part played by copper in hemoglobin formation. Hart, Steenbock, Waddell, and Elvehjem were the first to show that in nutritional anemia regeneration of hemoglobin does not occur when pure iron salts are administered, but if a small amount of copper as copper sulphate be added along with the iron salt regeneration is very rapid

Studies on Regeneration of Hemoglobin

Many investigators in the past few years have been interested in the problem of the relation of iron to anemia. This problem originated in connection with studies involving a comparison of inorganic versus organic iron, which later led to studies on the relation of solubility of iron compounds to regeneration of hemoglobin and the treatment of anemia

Neutrino Signal of Electron-Capture Supernovae from Core Collapse to Cooling

An 8.8 solar mass electron-capture supernova (SN) was simulated in spherical symmetry consistently from collapse through explosion to nearly complete deleptonization of the forming neutron star. The evolution time of about 9 s is short because of nucleon-nucleon correlations in the neutrino opacities. After a brief phase of accretion-enhanced luminosities (~200 ms), luminosity equipartition among all species becomes almost perfect and the spectra of electron antineutrinos and muon/tau antineutrinos very similar. We discuss consequences for the neutrino-driven wind as a nucleosynthesis site and for flavor oscillations of SN neutrinos.Comment: 4 pages, 4 eps figures; published as Physical Review Letters, vol. 104, Issue 25, id. 25110

On the appearance of hyperons in neutron stars

By employing a recently constructed hyperon-nucleon potential the equation of state of \beta-equilibrated and charge neutral nucleonic matter is calculated. The hyperon-nucleon potential is a low-momentum potential which is obtained within a renormalization group framework. Based on the Hartree-Fock approximation at zero temperature the densities at which hyperons appear in neutron stars are estimated. For several different bare hyperon-nucleon potentials and a wide range of nuclear matter parameters it is found that hyperons in neutron stars are always present. These findings have profound consequences for the mass and radius of neutron stars.Comment: 12 pages, 12 figures, RevTeX4; summary and conclusions are strengthened, to appear in PR

The Dynamics of IT Project Status Reporting: A Self-Reinforcing Cycle of Distrust

Accurate project status reporting is important to avoid the problem of information technology (IT) project escalation and to successfully manage and deliver IT projects. One approach that some organizations have taken is to audit their IT projects to avoid surprises that are frequently associated with inaccurate status reporting. Little is known, however, about the effects that such auditing arrangements can have on the dynamics of project status reporting. To examine the process of IT project status reporting in this context, we followed a grounded theory inspired approach in which we investigated nine IT projects in one U.S. state’s government agencies. All of the projects we studied were subject to the state’s IT oversight board. Based on 118 interviews with a variety of stakeholders including technical personnel, managers, users, and contractors, we present a grounded theory of project status reporting dynamics in which the reporting process can best be characterized as a self-reinforcing cycle of distrust between the project team and the auditors. Specifically, in some projects, we observed a pattern whereby project teams interpreted the auditor’s scrutiny as unfair and as not adding value to their projects. As a result, they responded by embracing some defensive reporting tactics. The auditors interpreted the project team’s actions as indicating either deception or incompetence, and they then increased their scrutiny of the reports, thus exacerbating the situation and further fuelling the cycle of distrust. We discuss implications for both theory and practice

Vascular uptake of rehydration fluids in hypohydrated men at rest and exercise

The purpose of this study was to formulate and to evaluate rehydration drinks, which would restore total body water and plasma volume (PV), for astronauts to consume before and during extravehicular activity, a few hours before reentry, and immediately after landing. In the first experiment (rest, sitting), five healthy men (23-41 yr), previously dehydrated for 24 hr., drank six (1a, 2, 4, 5, 6, 7) fluid formulations (one each at weekly intervals) and then sat for 70 min. Pre-test PV were measured with Evans blue dye and changes in PV were calculated with the hematocrit-hemoglobin transformation equation. This rest experiment simulated hypohydrated astronauts preparing for reentry. The second experiment (exercise, supine) followed the same protocol except four healthy men (30-46 yr) worked for 70 min. in the supine position on a cycle ergometer at a mean load of 71+/-1 percent of their peak aerobic work capacity. This exercise experiment simulated conditions for astronauts with reduced total body water engaging in extravehicular activity

Hemodynamic and ADH responses to central blood volume shifts in cardiac-denervated humans

Hemodynamic responses and antidiuretic hormone (ADH) were measured during body position changes designed to induce blood volume shifts in ten cardiac transplant recipients to assess the contribution of cardiac and vascular volume receptors in the control of ADH secretion. Each subject underwent 15 min of a control period in the seated posture, then assumed a lying posture for 30 min at 6 deg head down tilt (HDT) followed by 20 min of seated recovery. Venous blood samples and cardiac dimensions (echocardiography) were taken at 0 and 15 min before HDT, 5, 15, and 30 min of HDT, and 5, 15, and 30 min of seated recovery. Blood samples were analyzed for hematocrit, plasma osmolality, plasma renin activity (PRA), and ADH. Resting plasma volume (PV) was measured by Evans blue dye and percent changes in PV during posture changes were calculated from changes in hematocrit. Heart rate (HR) and blood pressure (BP) were recorded every 2 min. Results indicate that cardiac volume receptors are not the only mechanism for the control of ADH release during acute blood volume shifts in man

Heavy Water Obtained by the Combustion of Dried Biological Specimens

Dry, finely divided plant and animal tissues were oxidized by passage over hot copper oxide; the aqueous condensates were first distilled from potassium permanganate and then alone. If necessary, oxidation and distillation were repeated until there was no significant change in density. Densities were determined by a modification of the submerged magnetic float procedure, and the accuracy was one part per million. The specimens examined were practically all of the chief organs of cattle; yeasts; dairy products; and some parts of plants like corn and melons. The study is being extended to other biological specimens, normal and pathological

The trajectory of counterfactual simulation in development

Young children often struggle to answer the question “what would have happened?” particularly in cases where the adult-like “correct” answer has the same outcome as the event that actually occurred. Previous work has assumed that children fail because they cannot engage in accurate counterfactual simulations. Children have trouble considering what to change and what to keep fixed when comparing counterfactual alternatives to reality. However, most developmental studies on counterfactual reasoning have relied on binary yes/no responses to counterfactual questions about complex narratives and so have only been able to document when these failures occur but not why and how. Here, we investigate counterfactual reasoning in a domain in which specific counterfactual possibilities are very concrete: simple collision interactions. In Experiment 1, we show that 5- to 10-year-old children (recruited from schools and museums in Connecticut) succeed in making predictions but struggle to answer binary counterfactual questions. In Experiment 2, we use a multiple-choice method to allow children to select a specific counterfactual possibility. We find evidence that 4- to 6-year-old children (recruited online from across the United States) do conduct counterfactual simulations, but the counterfactual possibilities younger children consider differ from adult-like reasoning in systematic ways. Experiment 3 provides further evidence that young children engage in simulation rather than using a simpler visual matching strategy. Together, these experiments show that the developmental changes in counterfactual reasoning are not simply a matter of whether children engage in counterfactual simulation but also how they do so. (PsycInfo Database Record (c) 2021 APA, all rights reserved

DEXA-Measured VAT Robustly Predicts Impaired Glucose Tolerance and Metabolic Syndrome in Obese Women

Abdominal visceral adiposity (VAT) has been shown to be an independent risk factor for metabolic and cardiovascular disease. Using enCORE analysis version 13.6 on a GE Lunar iDXA, a new fully automated analysis software to measure VAT, we determined the strength of associations between DEXA-derived VAT and other known indicators for diabetes and cardiovascular disease risk in Caucasian and African American obese women. We collected anthropometrics, vital signs, lipid profile, and DXA whole body composition scan for 229 subjects with BMI 30.0 – 49.9 kg/m2 & age 21 to 69 y. We then performed the non-parametric Spearman correlation analysis and found that in subjects overall, DEXA-VAT is positively associated with triglyceride, fasting glucose, fasting insulin, and HOMA-IR, and negatively associated with HDL. Among all anthropometric, body composition and cardiometabolic variables, DEXA-VAT was the most robust predictor of impaired glucose tolerance (IGT) and metabolic syndrome (MetSx) in binary regression analysis, even after adjusting for race. LASSO regression after adjusting for covariates that best predicted IGT and MetSx showed that HOMAIR and DEXA-VAT most significantly predicted IGT (p\u3c0.001, p\u3c0.001, respectively), and DEXA-VAT most significantly predicted MetSx (p\u3c0.001). These observations have implications for VAT associated risk in diabetes and cardiovascular disease