cssi/SciSciGPT-SciSciNet huggingface dataset:
VALLEY ALLUVIATION IN SOUTHWESTERN WISCONSIN

ABSTRACT Meander erosional banks of fifth and sixth order southwestern Wisconsin streams having drainage areas of twenty square miles (30 km2) or less frequently reveal three distinct sedimentary sequences. The basal unit of coarse textured debris is thought to represent bed load sediment of a prior channel active near the terminus of a mid-Holocene drought about 6,000 years B. P. A silty clay series over the coarse layer is interpreted to have been derived by vertical accretion on a paleo floodplain during a climatic shift toward more humid conditions of the late Holocene. Distinctly laminated silt loam sediments produced by vertical accretion extend from the middle series to the current surface, and mainly result from increased flooding related to modern land use practices. The recent man-induced change in channel morphology is analogous to natural adjustments produced by Holocene climatic fluctuation, and suggests that temporal aspects of channel and floodplain evolution may be described by a step func...
Thermal stability improvement on pore and phase structure of sol-gel derived zirconia

Thermal stability improvement of mesoporous zirconia is important for its applications as catalyst supports or membrane layers at high temperatures. Yttria-coated zirconia is synthesized by doping a small amount of yttrium nitrate solution in zirconia sol. The sol-gel derived undoped and 2 and 3 mol% yttria-doped zirconia samples after calcination at 450 °C are in the metastable phase. Undoped zirconia starts to transform to thermodynamically stable monoclinic phase at 600 °C. The yttria-doped zirconia samples remain in the metastable phase after heat treatment in air at 900 °C for 30 h. Doping yttria also retards the sintering and grain-growth rates of the sol-gel derived zirconia. Doping with 2 mol% yttria gives the most effective results with respect to retarding the surface area loss of zirconia at high temperature. Yttria with a loading up to 2 mol % is possibly present on the grain surface of zirconia. The improvement of the thermal stability of zirconia by coating yttria is explained in terms of the effects of dopant on the mobility and concentration of the surface defects.
Synaptogenesis: The MAP location of GABA receptors

Microtubule-associated proteins (MAPs) have been identified as binding partners for ionotropic GABAA and GABAC receptors. These interactions suggest a potential role for MAPs in the cytoskeletal anchoring of receptor-ion channels at specific subcellular sites, such as synapses.
Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction

Lipopolysaccharide (LPS) is a major component of Gram-negative bacterial outer membranes. It is a tripartite molecule consisting of lipid A, which is embedded in the outer membrane, a core oligosaccharide and repeating O-antigen units that extend outward from the surface of the cell1, 2. LPS is an immunodominant molecule that is important for the virulence and pathogenesis of many bacterial species, including Pseudomonas aeruginosa, Salmonella species, and Escherichia coli3-5, and differences in LPS O-antigen composition form the basis for serotyping of strains. LPS is involved in attachment to host cells at the initiation of infection and provides protection from complement-mediated killing; strains that lack LPS can be attenuated for virulence6-8. For these reasons, it is important to visualize LPS, particularly from clinical isolates. Visualizing LPS banding patterns and recognition by specific antibodies can be useful tools to identify strain lineages and to characterize various mutants. In this report, we describe a hot aqueous-phenol method for the isolation and purification of LPS from Gram-negative bacterial cells. This protocol allows for the extraction of LPS away from nucleic acids and proteins that can interfere with visualization of LPS that occurs with shorter, less intensive extraction methods9. LPS prepared this way can be separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and directly stained using carbohydrate/glycoprotein stains or standard silver staining methods. Many anti-sera to LPS contain antibodies that cross-react with outer membrane proteins or other antigenic targets that can hinder reactivity observed following Western immunoblot of SDS-PAGE-separated crude cell lysates. Protease treatment of crude cell lysates alone is not always an effective way of removing this background using this or other visualization methods. Further, extensive protease treatment in an attempt to remove this background can lead to poor quality LPS that is not well resolved by any of the aforementioned methods. For these reasons, we believe that the following protocol, adapted from Westpahl and Jann10, is ideal for LPS extraction.
Plasticity of functional epithelial polarity

The fundamental characteristics that allow vectorial transport across an epithelial cell are the differential sorting and insertion of transport proteins either in the apical or the basolateral plasma membrane, and the preferential association of endocytosis and exocytosis with one or the other pole of the cell. Asymmetrical cellular structure and function, being manifestations of terminal differentiation, might be expected to be predetermined and invariant. Here we show that the polarity of transepithelial H+ transport, endocytosis and exocytosis in kidney can be reversed by environmental stimuli. The HCO3-secreting cell in the cortical collecting tubule is found to be an intercalated cell possessing a Cl−/HCO−3 exchanger in the apical membrane and proton pumps in endocytic vesicles that fuse with the basolateral membrane; the H+-secreting cell in the medullary collecting tubule has these transport functions on the opposite membranes. Further, the HCO−3-secreting cell can be induced to change its functional polarity to that of the H+-secreting cell by acid-loading the animal.
A review of nutritional deficiencies and toxicities in captive New World primates

The science of providing adequate nutrition for New World primates in captivity has improved dramatically in the past decade. To utilize these advances it is important to be aware of specific metabolic diseases and/or conditions associated with nutrient deficiencies or toxicities seen in New World primates. The non-human primate may require up to 64 dietary nutrients, highlighting the importance of an appropriate diet for optimal health. A review of the major nutritional problems which occur in captive New World primates is presented to provide a basis for good nutritional management of these species.
Traumatic Coronary Artery Fistula in a Child

An 8-year-old boy with an insignificant medical history presented to our institution after a motor vehicle accident that resulted in the deaths of his two siblings. He arrived in the emergency department hypotensive and unconscious. On initial evaluation, a heart rate of 174 bpm, blood pressure of 98/46 mm Hg, and agonal respirations were observed. He was immediately intubated and fluid-resuscitated. Work-up revealed diffuse axonal injury with right …
The Chinese Currency: Background and the Current Debate

Abstract China's economic growth and increasing trade surplus with the United States has aroused heated debate on whether the Chinese currency, the Renminbi (RMB), is undervalued and whether China should revalue or float its currency immediately. To help understand the current debate, this paper provides a brief history of the Chinese currency since the founding of the People's Republic and a summary of the main arguments in the current debate.
Chronic CSE Treatment Induces the Growth of Normal Oral Keratinocytes via PDK2 Upregulation, Increased Glycolysis and HIF1α Stabilization

Background Exposure to cigarette smoke is a major risk factor for head and neck squamous cell carcinoma (HNSCC). We have previously established a chronic cigarette smoke extract (CSE)-treated human oral normal keratinocyte model, demonstrating an elevated frequency of mitochondrial mutations in CSE treated cells. Using this model we further characterized the mechanism by which chronic CSE treatment induces increased cellular proliferation. Methodology/Principal Findings We demonstrate that chronic CSE treatment upregulates PDK2 expression, decreases PDH activity and thereby increases the glycolytic metabolites pyruvate and lactate. We also found that the chronic CSE treatment enhanced HIF1α accumulation through increased pyruvate and lactate production in a manner selectively reversible by ascorbate. Use of a HIF1α small molecule inhibitor blocked the growth induced by chronic CSE treatment in OKF6 cells. Furthermore, chronic CSE treatment was found to increase ROS (reactive oxygen species) production, and application of the ROS scavengers N-acetylcysteine abrogated the expression of PDK2 and HIF1α. Notably, treatment with dichloroacetate, a PDK2 inhibitor, also decreased the HIF1α expression as well as cell proliferation in chronic CSE treated OKF6 cells. Conclusions/Significance Our findings suggest that chronic CSE treatment contribute to cell growth via increased ROS production through mitochondrial mutations, upregulation of PDK2, attenuating PDH activity thereby increasing glycolytic metabolites, resulting in HIF1α stabilization. This study suggests a role for chronic tobacco exposure in the development of aerobic glycolysis and normoxic HIFα activation as a part of HNSCC initiation. These data may provide insights into development of chemopreventive strategies for smoking related cancers.
Photoreactivity of Si(111)−H in Ambient

Second harmonic generation rotational anisotropy (SHG-RA) provides a convenient means to monitor the chemical state of the Si surfaces and to follow the conversion of a H-terminated surface to SiO2 by oxidation as a function of time in ambient. SHG at 800 nm is sensitive to changes in the surface electronic properties induced by oxidation, and it probes both the initial stage of oxidation and the logarithmic oxide growth. We found that intense, ultrashort (4 ps) 800 nm laser pulses accelerate the initial stage of oxidation of Si(111)−H in ambient. The cross-section of the photoinduced process was found to be (1.7 ± 0.5) × 10-23 cm2. A mechanism involving drift of photoexcited electrons toward the surface is proposed to explain the photooxidation.
Model calculations of changes of thermodynamic variables for the transfer of nonpolar solutes from water to water-d2

A recently introduced modified hydration shell hydrogen bond model for rationalizing the thermodynamic consequences of hydrophobic hydration is adapted for use with heavy water. The required adjustment of parameters employs the assumption that breaking hydrogen bonds in water-d2 involves a greater enthalpy change and a larger entropy increase than bond breaking in ordinary water. It also makes some use of information derived from studies of gas solubilities in the two solvents, although a review of the data leads to serious questions about the reliability of results obtained in this way. The model permits calculations of hydrogen bonding contributions to the changes, ΔGto, ΔHto, ΔSto, and ΔCp,to, for transfer of nonpolar solutes from water to water-d2 and implies that such data should show regular trends. Although some of the numerical results depend strongly on the values chosen for the parameters, the pattern defined by these trends is nearly independent of parameters. Predicted values of ΔCp,to are large and positive for all nonpolar solutes, while ΔSto is expected to be negative near 0°C, becoming progressively less negative on warming and eventually positive. Both of these quantities should be proportional to the molecular surface area of the solute. Analogous predictions regarding ΔGto and ΔHto can also be made, but only if it is permissible to neglect possible contributions to these quantities from van der Waals interactions.
Comparative radioautographic study of the effects of L-azetidine-2-carboxylic acid on matrix secretion and Golgi of the mouse incisor.

The effect of a proline analog,l-azetidine-2-carboxylic acid (LACA), on protein matrix secretion by odontoblasts and ameloblasts was compared by light and electron microscopic radioautography after injection of3H-glycine in young mice. LACA inhibited the secretion of dentin matrix with consequent accumulation of3H-glycine labeled procollagen in the cisternae of the rough endoplasmic reticulum. In contrast, LACA had no apparent effect on ameloblasts as enamel matrix continued to be packaged in the Golgi apparatus and secreted from Tomes' process within 30 min after injection of the radioprecursor. Electron microscopy revealed that LACA did not cause any change in ameloblast ultrastructure but produced a marked alteration of the odontoblast Golgi complex. All odontoblast Golgi saccules and collagen secretion granules disappeared within 2 h after LACA administration. Odontoblast Golgi cisternae, however, appeared not to be affected. These observations confirm previous studies conducted in this laboratory showing that Golgi saccules in collagen-secreting cells are the initial staging areas for the formation of secretory granules. These results also indicate that a close correlation exists between form and function in the Golgi apparatus of collagen-secreting cells.
Peptidases from pig reproductive tract: purification and properties of aminopeptidases from uterine secretions, allantoic fluid, and amniotic fluid.

Abstract In ovariectomized sows, aminopeptidase is secreted into the uterine lumen under the influence of progesterone. The enzyme also accumulates in allantoic and amniotic fluids of pregnant animals. We have purified the predominant form of this enzyme from uterine flushings, allantoic fluid, and amniotic fluid by the following steps: ammonium sulfate precipitation, Sepharose 6B chromatography, ion-exhange chromatography on diethylaminoethyl cellulose, and affinity chromatography using l -leucylglycine immobilized on agarose. The overall procedure gave approximately 974-, 110-, and 230-fold purifications of the allantoic, uterine, and amniotic enzymes, respectively. The enzymes from all three sources are glycoproteins with pI's around 4 and molecular weights of about 480,000. They may be dissociated into six apparently identical subunits of molecular weight 80,000 as judged by sodium dodecyl sulfate gel electrophoresis. With l -leucyl-β-naphthylamide as substrate the pH optimum and apparent K m value for each enzyme were 7.1 and 14 μ m , respectively. However, the uterine and allantoic aminopeptidases exhibited V values of 0.35 μmol of substrate hydrolyzed/min/mg of protein, whereas the V for the amniotic enzyme was at least sixfold greater. The amniotic enzyme also differed from the other two in pH and temperature stability. The activity of all three enzymes was stimulated by Co 2+ and inhibited by Cu 2+ , Fe 3+ , and chelating agents, while iodoacetate and mercaptoethanol had no effect on catalysis. The effect of Co 2+ on the allantoic enzyme was investigated in further detail. The stimulation of peptidase activity by Co 2+ was shown to be a complex process but consistent with Co 2+ replacing another metal at the active site and at some other additional site on the enzyme. The function of the aminopeptidases in the pregnant uterus is unknown.
Oxidative stress during acute FIV infection in cats

Abstract Oxidative stress is thought to contribute to the pathogenesis of HIV infection in humans. For example, CD4+ T cells are particularly affected in HIV patients and oxidative stress may also contribute to impairment of neutrophil function in HIV/AIDS patients. Since cats infected with FIV develop many of the same immunological abnormalites as HIV-infected humans, we investigated effects of acute FIV infection on oxidative stress in cats. Cats were infected with a pathogenic strain of FIV and viral load, changes in neutrophil number, total blood glutathione, malondiadehye, antioxidant enzyme concentrations, and reduced glutathione (GSH) concentration in leukocytes were measured sequentially during the first 16 weeks of infection. We found that superoxide dismutase and glutathione peroxidase concentrations in whole blood increased significantly during acute FIV infection. In addition, neutrophil numbers increased significantly during this time period, though their intracellular GSH concentrations did not change. In contrast, the numbers of CD4+ T cells decreased significantly and their intracellular GSH concentration increased significantly, while intracellular GSH concentrations were unchanged in CD8+ T cells. However, by 16 weeks of infection, many of the abnormalities in oxidative balance had stabilized or returned to pre-inoculation values. These results suggest that acute infection with FIV causes oxidative stress in cats and that CD4+ T cells appear to be preferentially affected. Further studies are required to determine whether early treatment with anti-oxidants may help ameliorate the decline in CD4+ T cell number and function associated with acute FIV infection in cats.
Alternative Indices for the Warm-Season NAO and Precipitation Variability in West Greenland

Abstract Observed precipitation records from Kangerlussuaq, Greenland, and atmospheric variables from the NCEP–NCAR reanalysis were used in a statistical analysis to elucidate controls on the seasonal variation of precipitation and develop indices that may be potentially useful for analyzing precipitation variability in paleoclimate and future climate change investigations. Three distinct patterns of correlation between precipitation and the 500-hPa geopotential height were found to represent three dominant atmospheric patterns that strongly influence precipitation for different times of the year. All three patterns show a relation to the North Atlantic Oscillation signature found in the first empirical orthogonal function of the 500-hPa height field. Spatially dependent indices were developed based on the 500-hPa geopotential field. The correlation coefficients between precipitation at Kangerlussuaq and these indices range from −0.38 for winter to 0.64 for the warm season (May–September). The warm-season...
Algorithms for a class of isotonic regression problems

The isotonic regression problem has applications in statistics, operations research, and image processing. In this paper a general framework for the isotonic regression algorithm is proposed. Under this framework, we discuss the isotonic regression problem in the case where the directed graph specifying the order restriction is a directed tree with n vertices. A new algorithm is presented for this case, which can be regarded as a generalization of the PAV algorithm of Ayer et al. Using a simple tree structure such as the binomial heap, the algorithm can be implemented in O(n log n) time, improving the previously best known O(n 2 ) time algorithm. We also present linear time algorithms for special cases where the directed graph is a path or a star.
Biased discriminant analysis: Evaluation of the optimum probability of misclassification

This article extends the work of DiPillo (1976) on the Biased Minimum x2 Rule. The optimum value of k (the biasing factor) Is determined and the true probability of misclassification is found. The proportion improvements reported in the 1976 paper are shown to be conservative. Some suggestions for algorithms to determine the optimal value of k are presented.
Theory of the response of schottky-barrier diodes to transverse magnetic surface waves

Abstract Both the reflectivity and quantum efficiency response functions of a Schottky-barrier diode are calculated for the case when the device is exposed to transverse magnetic surface electromagnetic waves. The surface plasma resonance is shown to occur in both responses Numerical results are presented for a Au/nSi diode.
A dipole oriented chiral conjugated polymer and multipolar chiral macrocycles

A chiral binaphthyl monomer (R)-9a that contains a terminal alkyne and an aryl iodide function has been synthesized. Homopolymerization of (R)-9a in the presence of Pd(PPh 3 ) 4 /Cul catalysts leads to the formation of polymer (R)-6. This polymer represents a new type of chiral conjugated materials with the dipole units oriented into one direction along the rigid polymer chain. Materials of this structure may have interesting nonlinear optical properties. (R)-6 is soluble in common organic solvents. Gel permeation chromatography (GPC) analysis shows M w = 34000 and M n = 17000 (polydispersity index PDI = 1.97). Its specific optical rotation is [a] D = -197.6 (c = 0.16, CH 2 Cl 2 ). At lower concentration of (R)-9a, self-coupling produces a series of multipolar chiral macrocycles.
Artificial neural networks to correlate in-tube turbulent forced convection of binary gas mixtures

Abstract Turbulent forced convection correlations are documented in the literature for air, gases and vapors ( Pr ∼ 0.7 ), for common liquids ( Pr > 1 ) and for liquid metals ( Pr 0.03 ). In spite of this, there is a small gap in the Pr sub-interval between 0.1 and 1.0, which is occupied by binary gas mixtures. In this paper, data for turbulent forced convection for the in-tube flow have been gathered and a fully connected back-propagation Artificial Neural Network (ANN) is used to learn the pattern of Nu as a double-valued function of Re and Pr. The available data are separated in two subsets to train and test the neural network. A set with 80% of the data is used to train the ANN and the remaining 20% are used for testing. After the neural network is trained, we make use of the excellent nonlinear interpolation capabilities of ANNs to predict Nu for the sought range 0.1 Pr 0.7 for Re between 104 and 106. These predictions are later extended to generate a comprehensive correlation for Re between 104 and 106 that aptly covers the complete spectrum of Prandtl numbers.
Butadiene epidemiology: a summary of results and outstanding issues

Published epidemiologic studies of butadiene workers, individually and in aggregate, find rates similar to expected for essentially all forms of cancer, with the possible exception of lymphohematopoietic cancers. Reviewers of the literature have disagreed about whether butadiene is a cause of human lymphohematopoietic cancers. This article reviews the available butadiene epidemiologic studies and focuses on the bases for disagreement among reviewers. The disagreement seems to be due to different conventions in applying, explicitly or implicitly, Hill's causal criteria, fostered, in part, by deficiencies in the available epidemiologic studies. Many of these deficiencies will be remedied by updated studies presented at this Symposium or are remediable by other analyses of the existing data.
Lipoprotein lipase activity and blood triglyceride levels in fetal and newborn rats.

Summary: Lipoprotein lipase activity in lung and heart was studied in fetal (17-22 days of gestation) and newborn rats from the day of birth until 30 days of age. Enzyme activity in epididymal, omental, and parametrial adipose tissue was tested after 18 days of age. Blood triglyceride levels were measured at all ages from 17 days in utero until 30 days after birth. The developmental pattern of lipoprotein lipase differed markedly in lung and heart. Although lipoprotein lipase activity was 4 to 5 times higher hi adult rat heart than in lung (30-40 U/g in heart vs. 8-11 U/g in lung), the activity was almost completely absent from fetal heart and was very low during the first 3 days after birth. Lipoprotein lipase reached 60-70% of adult activity at 6 days and remained at that level until 19 days after birth; adult activity levels were reached at 24 days. In the lung, contrary to the heart, lipoprotein lipase activity was high in the fetus (84% of adult activity), decreased immediately after birth to 45% of adult activity at 2 days, and remained at that level up to 15 days after birth. Enzyme activity started to rise again at 15 days and reached adult levels at 21 days of age. Adipose tissue was present in trace amounts before the age of 2 weeks. In the three fat depots tested, lipoprotein lipase activity was 50% lower than in adults between 20 and 30 days after birth. Blood triglyceride levels increased 4- fold between 2 to 10 hr after birth and remained elevated during the first 3 days after birth. Speculation: The triglyceridemia that starts in the immediate postnatal period and lasts for several days in the rat probably results from the combination of high fat intake and low clearing ability of the extrahepatic tissues. In addition to its role in clearing circulating triglyceride, lipoprotein lipase may play a role in the growth and maturation of individual organs. The present study shows that lipoprotein lipase activity is high in fetal lung during the period of marked surfactant synthesis and suggests that circulating triglyceride-fatty acids are used by the fetal lung for surfactant synthesis.
Kinetics of almond skin separation as a function of blanching time and temperature

Abstract This study was undertaken to better characterize the process of almond seed coat (a.k.a. skin) separation via hot water submersion, a process often referred to as ‘blanching’. The degree of skin separation on individual almonds was measured after varying treatment times and temperatures, and modeled empirically. At all tested temperatures (100–70 °C), separation progressed along a sigmoidal logistic curve. Applying the concepts of microbial lethality kinetics to seed coat separation, D separation values were 24 s at 90 °C (194 °F), 118 s at 80 °C (176 °F), and 443 s at 70 °C (158 °F). From these, the z separation value between 70 °C and 90 °C was 15.85 °C. The skin separation rate decreased quickly below 90 °C (194 °F). By comparing the rate of seed coat separation, almond varieties, as well as growing, harvesting, and processing conditions could be quantitatively evaluated for their impact on skin separation.
Effect of decreased plasma low-density lipoprotein levels on adrenal and testicular function in man.

Objective: The study assessed whether serum LDL cholesterol levels affect adrenal and Leydig cell function in man. Design and Methods: A 24-h continuous ACTH infusion was performed in 15 consecutive chronically ill patients. Serum cortisol and DHEA-s were measured at baseline and at 3, 6, 12, 20, and 24 h during the infusion. Fasting serum lipoprotein levels including LDL cholesterol, HDL cholesterol as well as FSH, LH, total and free testosterone concentrations were also measured on the baseline morning samples prior to the infusion. Results: The initial 3 and 6 h percent rise in cortisol values during 24-h ACTH infusion were significantly diminished in patients with LDL-C values <1.55 mmol/L as compared with patients with higher LDL-C levels (127 ± 17% (SE) vs. 199 ± 31% (SE); p < 0.02 and 115 ± 17% vs. 213 ± 32%; p < 0.02. However, the 24-h areas of cortisol under the curve were comparable the 2 groups. Basal and ACTH stimulated DHEA-s levels and percent increases tended to be lower in the low LDL-C group but the differences were not statistically significant. The mean total testosterone was lower in the low LDL-C group (5.30 ± 1.78 vs. 15.60 ± 1.95 nmol/L; p < 0.0005). Free testosterone levels were also lower in the low LDL-C group (0.03 ± 0.009 nmol/L vs. 0.08 ± 0.01 nmol/L; p < 0.001). Five of six patients with low LDL-cholesterol had low testosterone values, but variable LH levels. Conclusions: Our results suggest that severe acquired LDL cholesterol insufficiency impairs slightly the initial glucocorticoid response to ACTH stimulation but not the overall cortisol production during sustained ACTH stimulation. It also may contribute to the reduction in testosterone seen in chronically ill patients.
Key space telescope design considerations

The Space Telescope (ST), a 2.4 meter aperture astronomical telescope, will be launched into low earth orbit by the Space Shuttle in the mid-1980's. This high resolution telescope will be capable of operating from Lyman-alpha (121.6 nm) through the near infrared; support five different scientific instruments at its focal plane (two cameras, two spectrographs, and one photometer); and by periodic on-orbit servicing and ground refurbishment be able to operate with technologically current scientific instruments for at least 15 years. This paper identifies the critical Space Telescope design requirements and describes design techniques which were selected to satisfy these requirements.
A Pitzer model for the Na–Al(OH)4–Cl–OH system and solubility of boehmite (AlOOH) to high ionic strength and to 250 °C

Abstract In this study, a Pitzer model for the Na–Cl–OH–Al(OH) 4 system, and solubility of boehmite (AlOOH) to high ionic strengths, and to high temperatures up to 250 °C, has been developed by evaluating equilibrium quotients concerning boehmite in NaCl solutions to 5.0 mol·kg − 1 , and boehmite solubility data in NaOH solutions to ~ 13 mol·kg − 1 . This model is validated by comparing model-predicted solubilities with solubility data of boehmite in NaOH solutions that are independent from the model development. This model is of value to many fields, including accurate modeling geochemical behavior of aluminum in hydrothermal solutions with high ionic strengths at high temperatures up to 250 °C, extraction of aluminum via the Bayer process from various ores, stability of borosilicate glass, aluminum silicate materials as waste forms for long-lived radio nuclides, and bentonite as engineered barrier, in geological repositories. Based on the model developed in this work, solubility of boehmite can be potentially used as a pH m (hydrogen ion concentration on molal scale) sensor/buffer in hydrothermal experiments under neutral to alkaline conditions in NaCl solutions in the absence of silica. This pH m sensor/buffer would enable experimentalists to conduct hydrothermal experiments in a wide range ionic strength under well-controlled pH m conditions.
Core pinning by intragranular nanoprecipitates in polycrystalline MgCNi 3

The magnetic properties and nanostructure of polycrystalline ${\mathrm{MgCNi}}_{3},$ prepared from a batch with overall composition ${\mathrm{MgC}}_{1.5}{\mathrm{Ni}}_{3},$ were studied by vibrating sample magnetometry and electron microscopy. Very high critical current density, e.g., $1.8 {\mathrm{M}\mathrm{A}/\mathrm{c}\mathrm{m}}^{2}$ at 1 T and 4.2 K, is deduced from the magnetic hysteresis and evident subdivision of the sample into $10 \ensuremath{\mu}\mathrm{m}$ clusters of ${\mathrm{MgCNi}}_{3}$ grains by excess graphite. The bulk pinning force ${F}_{p}(H)$ is comparable to that of other strong flux-pinning superconductors, such as NbN, Nb-Ti, and ${\mathrm{Nb}}_{3}\mathrm{Sn},$ all of which have higher critical temperatures. While ${F}_{p}(H)$ indicates the expected grain-boundary pinning mechanism just below ${T}_{c}\ensuremath{\approx}7.2 \mathrm{K},$ a systematic change to a core-pinning mechanism is indicated by a shift of the ${F}_{p}(H)$ curve peak to higher (reduced) field with decreasing temperature. The lack of temperature scaling of ${F}_{p}(H)$ suggests the presence of pinning sites at a nanometer scale inside the grains, which are smaller than the diameter of fluxon cores $2\ensuremath{\xi}(T)$ at high temperature and become effective when the coherence length $\ensuremath{\xi}(T)$ approaches the nanostructural scale with decreasing temperature. High-resolution transmission electron microscopy imaging and electron diffraction revealed a substantial volume fraction of cubic and graphite nanoprecipitates comparable to $\ensuremath{\xi}(0)\ensuremath{\approx}5 \mathrm{nm}$ in size, consistent with the hypothesis above. Dirty-limit behavior seen in previous studies may thus be tied to electron scattering by the precipitates. To our knowledge, no other fine-grained bulk intermetallic superconductor exhibits a similar change from grain boundary to core pinning with decreasing temperature, suggesting that the arrangement of pinning sites in ${\mathrm{MgCNi}}_{3}$ is unique. These results also indicate that strong flux pinning might be combined with a technologically useful upper critical field if variants of ${\mathrm{MgCNi}}_{3}$ with higher ${T}_{c}$ can be found.
Effects of menstrual phase and smoking abstinence in smokers with and without a history of major depressive disorder.

Although considerable progress has been made towards understanding the role of menstrual cycle phase in smoking, little is known about the possible effects of menstrual phase upon nicotine intake, withdrawal symptomatology, and craving in women with psychiatric cofactors. Fourteen women with and without a history of Major Depressive Disorder (MDD) were studied during five biologically-confirmed phases over the course of one menstrual cycle; smoking logs, salivary cotinine, and ratings of craving and withdrawal were collected daily. During a second cycle, subjects remained abstinent for 3 consecutive days during the postmenses and premenstrual phases. Although a significant omnibus F-test emerged for cigarettes per day across phases during ad libitum smoking, only trends were observed post hoc and supported midcycle rather than premenstrual elevations. There were no significant phase differences for cotinine. Withdrawal symptomatology was markedly elevated during smoking abstinence and in women with a history of depression, but showed no evidence of phase effects. Thus, the hypothesis that depressed individuals would be differentially affected by phase and abstinence was not strongly supported by our results, though overall elevations emphasize the need for special attention to withdrawal severity in this population. Craving was significantly elevated during smoking abstinence and was significantly higher during postmenses, consistent with the midcycle elevation in smoking rate, but showed no group differences. Our findings overall lend little support for the need to control for menstrual phase under conditions of ad libitum smoking. The strong association of self-reported menstrually related dysphoria during abstinence with both craving and withdrawal symptoms, however, is consistent with an exacerbation of smoking abstinence effects in women with severe menstrual symptomatology.
Right on cue.

Understanding how cytokines interact with multimeric cell receptors to generate signals governing cell behavioral responses is crucial for the development of these promising pharmacological agents. A powerful quantitative approach is reported that was used to analyze the complicated case of binding of the GDNF family member artemin to the heteromeric GFRα3-Ret receptor.
Studies of Greenland using the Seasat scatterometer

The Ku-band (14.6 GHz) Seasat scatterometer (SASS), which flew for 3 months in 1978, was designed to measure the normalized radar backscatter coefficient ((sigma) 0) in order to determine the near-surface wind over the ocean. While SASS made measurements of (sigma) 0 over land and ice regions, the application of this data has been limited due to the low resolution (50 km) of the measurements. Recently, however, we developed a new technique to generate enhanced resolution (to as fine as 3 - 4 km) images of the surface radar backscatter characteristics from SASS measurements. In this paper we report some results of a study of the seasonal response of the Greenland ice sheet using this technique. Using SASS data, we have generated a time-series of enhanced resolution images of vertically-polarized radar images of Greenland during July - Sept. 1978. The effects of the summer melt along the ice sheet periphery are clearly evident in the time series. In central Greenland, which exhibits a very high radar backscatter at 14.6 GHz, very little change was observed over the three month data set.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Radical change and its effects

A teacher finds that highly personalized learning can be stimulating but also politically threatening.
The all-cone retina of the garter snake: spectral mechanisms and photopigment

The retina of the garter snake contains 3 morphologically distinct classes of cone photoreceptor. The spectral mechanisms in the retinas of garter snakes (Thamnophis sirtalis and T. marcianus) were studied by recording a retinal gross potential, the electroretinogram, using a flicker photometric procedure. Spectral sensitivity functions recorded with stimuli presented at high temporal frequency (62.5 Hz) are broadly peaked in the region of 550–570 nm. These functions remain spectrally invariant (a) in the face of significant changes in stimulus pulse rate (8–62.5 Hz), (b) whether the eye is light or dark adapted, and (c) under conditions of intense chromatic adaptation. It is concluded that the garter snake has only a single class of cone pigment. The results from a curve fitting analysis suggests that this pigment has peak absorbance at about 556 nm.
Applications of system- and component-damping to space structures

This paper explains the reason for the significant difference of payload responses when different damping methods are applied. In dynamic analyses of space structures, three different types of damping matrices have usually been employed: system damping, free-free component damping and constrained component damping. This paper explains the reason for the discrepancies by considering a dynamic system composed of two substructures, each has two degrees-of-freedom. The close form expressions of the damping matrices are obtained on the same level of coordinates for direct comparisons, from which the reasons for the response discrepancies between different damping approaches in treating dynamic problems are interpreted.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Structural and Functional Analysis of the Pig-a Protein That is Mutated in Paroxysmal Nocturnal Hemoglobinuria

Abstract ABSTRACT: There is now convincing evidence that the Pig-a gene is mutated in patients with paroxysmal nocturnal hemoglobinuria (PNH), a disease in which one or more clones of hematopoietic cells have incomplete assembly of glycosylphosphatidylinositol (GPI) anchors and absence of GPI-linked protein expression on the cell surface. Little is known, however, about the Pig-a protein product that is necessary for GPI anchor bioassembly. Relatively few substitution (missense) Pig-a gene mutations have been identified, but we noted two apparent clusters at codons 128-129 and 151-156 and hypothesized that these might represent critical regions of the Pig-a protein. We therefore used site-directed mutagenesis to create conservative mutations in the Pig-a protein, then performed structural and functional analysis. Each Pig-a mutation generated a Pig-a protein of normal size and stability, but certain mutations had substantial deleterious effects on protein function. Conservative mutation of codons histidine 128 (H128), serine 129 (S129), and serine 155 (S155) had greatly diminished function, while mutations of flanking residues had no effect on function. Our results represent the first structure/function analysis of the Pig-a protein, and suggest that codons H128, S129, and S155 represent critical regions of the Pig-a protein. Our results also suggest a means by which transgenic mice with a “partial knock-out” of Pig-a function could be generated, which would allow investigation of PNH in an animal model.
Cognitive complexity-simplicity and predictive behavior.

“A theoretical approach which conceives predictive behavior to be a function of one's perceptions of others is presented as a means of unifying certain empirical data ordinarily subsumed under the labels of social perception, empathy, or social sensitivity…. all these forms of behavior rest operatio
Are Fulbright Applicants Idealists or Opportunists

The Fulbright program attracts applicants passionate about service and research abroad. Applicants apply to one country. To aid their decisions, competition statistics giving approximate probabilities of being awarded a scholarship are released for each country. This paper examines how competition statistics influence country choices. In aggregate, our results suggest that applicants are not swayed to apply to countries with low competition or deterred from countries with high competition. However, accounting for the difference in scholarship types and the macroeconomic context, there is strong evidence of opportunistic behavior by teaching applicants and for all applicants when the unemployment rate is high.
An experimental study of crystallization and crystal growth of methane hydrates from melting ice

An experiment with well defined gas-water interfacial surface area was developed to study the crystallization and crystal growth of methane hydrates. Measurable formation rates were observed only when melting ice was involved. No hydrates nucleated from liquid water or from non-melting ice. It is concluded that melting ice, which like hydrate water is hydrogen-bonded, provides a template for hydrate nucleation as well as providing a heat sink for absorbing the heat of formation during hydrate growth. The experiment was conducted in the absence of mixing so that hydrate crystals grew under quiescent conditions.
Interaction of endothelial cells and fibroblasts with modified fibrin networks: role in atherosclerosis.

Abstract Fibrinogen has been recognised in recent years as an independent risk factor in athero/thrombogenesis. However, the mechanism by which elevated fibrinogen translates into higher incidence of atherosclerosis is not known. One possible mechanism may be through the modification of fibrin. While it is already known that fibrin network is altered in disease states like peripheral vascular disease, diabetes, hypercholesterolaemia and myocardial infarction, the influence of altered fibrin network structure on growth and function of endothelial cells (EC) and fibroblasts (FB) requires investigation. Fibrin network structure in plasma clots was modified by changing pH and characterised using established biophysical methods. PGI 2 , von Willebrand Factor (vWF), t-PA and PAI-1 were measured to evaluate changes in cell function induced by modified fibrin structure. In general, networks composed of thin fibres induced growth over their entire layer. Networks composed of thick fibres and open matrix promoted infiltration of cells into gel matrix and growth of macrovascular structures. Furthermore, thin fibres promoted a more prothrombotic environment as observed from changes in cell biochemical function. Fibrin, whilst initially acting as a scaffolding for cellular and biochemical processes, may also alter cell function and determine the progress of atherosclerosis.
763-6 Septal Myectomy for Hypertrophic Cardiomyopathy: Echocardiographic Predictors of Postoperative Outcome

Although septal myectomy (SM) reduces the left ventricular outflow tract (LVOT) pressure gradient and relieves symptoms in the majority of patients with severe hypertrophic cardiomyopathy (HCM). there remains a subset of patients who will continue to have residual limiting symptoms. In order to determine whether echo/Doppler (ECHO) can predict outcome after surgical treatment of HCM, we analyzed the clinical and ECHO characteristics of 47 consecutive HCM patients aged 20 to 70 years (mean 47 ± 15 years, M:F = 1:1) undergoing isolated SM from 1986 to 1992 for NYHA class 3 or 4 symptoms. Preoperative symptoms included dyspnea (100%), angina (64%), near syncope (62%), and syncope (23%). At postoperative follow-up (12 ± 4 months). there was marked overall improvement; 94% were NYHA class 1 or 2. Persistent symptoms were dyspnea (55%), angina (15%), and near syncope (15%). By multivariate analysis of all clinical and ECHO parameters, only the preoperative ECHO variable of hypertrophy pattern (diffuse hypertrophy≥ 15 mm versus septal localization ± anterolateral extension) emerged as an independent predictor of residual dyspnea postoperatively (p = 0.05). Variables not predictive included peak rest and provoked LVOT gradient, ejection time, mitral regurgitation severity, mitral flow velocity curves, left atrial volume, and left ventricular mass index. Conclusions With the successful relief of LVOT obstruction by SM, most HCM patients experience significant improvement in symptoms of angina. near syncope, and syncope. The morphological characteristic of diffuse (concentric) left ventricular hypertrophy is a superior predictor of residual postoperative dyspnea as compared to Doppler parameters. This diffuse hypertrophy may be indicative of severe diastolic filling abnormalities which are unchanged by SM.
Intermediate-term results of the endocardial surgical approach for anomalous atrioventricular bypass tracts

Between October 1974 and March 1, 1985, 26 patients with 29 anomalous AV bypass tracts underwent surgical treatment at the Medical Center of UAB, with follow-up from 1 to 14 years. Eleven of the patients underwent surgical correction of major associated cardiac anomalies. One patient had His bundle ablation, and 25 patients had direct surgical division of 28 bypass tracts with the use of an endocardial approach. Successful division was achieved in 27 (96%; confidence limits 88% to 99%) of 28 bypass tracts identified pre- and intraoperatively. There were no hospital deaths, but on formal follow-up there were three late deaths, all occurring in patients with major associated cardiac pathology. Neither preexcitation nor reciprocating tachycardia recurred, and functional status was excellent among patients without associated cardiac lesions. Because of the safety and, at least on intermediate-term follow-up, apparently curative nature of this operation (particularly for patients without other major cardiac pathology), surgical treatment is recommended for patients with bypass tracts having lethal potential, those with reciprocating tachycardia unresponsive to drugs, and to symptomatic patients facing many years of medications.
Did New Deal Grant Programs Stimulate Local Economies? A Study of Federal Grants and Retail Sales During the Great Depression

Using data on New Deal grants to each U.S. county from 1933 to 1939, we estimate how relief and public works spending and payments to farmers through the Agricultural Adjustment Administration influenced retail consumption. On a per capita basis, we find that an additional dollar of public works and relief spending was associated with a 44 cent increase in 1939 retail sales. In contrast, the AAA seems to have had a negative effect on retail sales, suggesting that nonlandowners in the farm sector suffered disproportionate declines in income as a result of the AAA.
New Prospect for Gamma-Ray-Line Astronomy

THE prospects for gamma-ray-line astronomy associated with the anticipated occurrence of radioactivity in interstellar space have already been outlined1–4. Each successive clarification of these possibilities has resulted from major clarifications in the theory of nucleosynthesis, and in this communication I wish to report another step. The supposition that the elements are coproduced in exploding stars has been greatly strengthened by quantitative success5 in the past few years. A new development within that general picture now suggests that detectable amounts of 60Fe exist in nearby explosive remnants. 60Fe has a half-life τ1/2 = 3 × 105 yr, and the subsequent decay of its 60Co daughter is accompanied by a two-gamma-ray cascade with energies Eγ=1.17 MeV and 1.33 MeV (ref. 6). This pair of equal-intensity lines is the signature that can identify 60Fe in interstellar space. The other important feature is, of course, its half-life, which is long enough to allow the radioactivity to persist long after (in terms of recorded history) the explosive event.