cssi/SciSciGPT-SciSciNet huggingface dataset:
Floatability of apatites of different type and origin: role of surface area and porosity

Abstract A multi-pronged approach involving dissolution, adsorption, precipitation and flotation studies was used to determine the role of surface area and porosity on the floatability of apatites of different type, sedimentary or endogenic, and origin. When the samples were not aged prior to collector (potassium oleate) addition, the floatability was controlled by the dissolution (of calcium) and adsorption (of oleate) behaviors which, in turn, were governed by the surface area. It appears that the surface constituted by pores had a lesser influence than the external surface, on the adsorption and the dissolution characteristics. This was suggested to be due to the slow diffusion of calcium through the pores, which results in reduced dissolution rate, as well as the non-participation of a substantial portion of the pores in the adsorption process. When the samples were aged prior to oleate addition, bulk precipitation of calcium oleate complex was found to play a crucial role. Since bulk precipitation is not an interfacial process, the effect of surface area was less with the aged samples.
Development of Mechanistic-Empirical Pavement Design in Minnesota

The next AASHTO guide on pavement design will encourage a broader use of mechanistic-empirical (M-E) approaches. While M-E design is conceptually straightforward, the development and implementation of such a procedure are somewhat more complicated. The development of an M-E design procedure at the University of Minnesota, in conjunction with the Minnesota Department of Transportation, is described. Specifically, issues concerning mechanistic computer models, material characterization, load configuration, pavement life equations, accumulating damage, and seasonal variations in material properties are discussed. Each of these components fits into the proposed M-E design procedure for Minnesota but is entirely compartmentalized. For example, as better computer models are developed, they may simply be inserted into the design method to yield more accurate pavement response predictions. Material characterization, in terms of modulus, will rely on falling-weight deflectometer and laboratory data. Additionally, backcalculated values from the Minnesota Road Research Project will aid in determining the seasonal variation of moduli. The abundance of weigh-in-motion data will allow for more accurate load characterization in terms of load spectra rather than load equivalency. Pavement life equations to predict fatigue and rutting in conjunction with Miner's hypothesis of accumulating damage are continually being refined to match observed performance in Minnesota. Ultimately, a computer program that incorporates the proposed M-E design method into a user-friendly Windows environment will be developed.
Trends in Selenium Utilization in Marine Microbial World Revealed through the Analysis of the Global Ocean Sampling (GOS) Project

Selenium is an important trace element that occurs in proteins in the form of selenocysteine (Sec) and in tRNAs in the form of selenouridine. Recent large-scale metagenomics projects provide an opportunity for understanding global trends in trace element utilization. Herein, we characterized the selenoproteome of the microbial marine community derived from the Global Ocean Sampling (GOS) expedition. More than 3,600 selenoprotein gene sequences belonging to 58 protein families were detected, including sequences representing 7 newly identified selenoprotein families, such as homologs of ferredoxin–thioredoxin reductase and serine protease. In addition, a new eukaryotic selenoprotein family, thiol reductase GILT, was identified. Most GOS selenoprotein families originated from Cys-containing thiol oxidoreductases. In both Pacific and Atlantic microbial communities, SelW-like and SelD were the most widespread selenoproteins. Geographic location had little influence on Sec utilization as measured by selenoprotein variety and the number of selenoprotein genes detected; however, both higher temperature and marine (as opposed to freshwater and other aquatic) environment were associated with increased use of this amino acid. Selenoproteins were also detected with preference for either environment. We identified novel fusion forms of several selenoproteins that highlight redox activities of these proteins. Almost half of Cys-containing SelDs were fused with NADH dehydrogenase, whereas such SelD forms were rare in terrestrial organisms. The selenouridine utilization trait was also analyzed and showed an independent evolutionary relationship with Sec utilization. Overall, our study provides insights into global trends in microbial selenium utilization in marine environments.
Drying and Hydrophobic Collapse of Paraffin Plates

We perform molecular dynamics simulations of the hydrophobic collapse of two paraffin plates to examine how the collapse is mediated by realistic paraffin-water attractive van der Waals forces. We explore several aspects of the drying transition between the plates, including the critical separation for drying and the critical size of the vapor bubble required for the nucleation of the drying event. We also investigate the kinetics of hydrophobic collapse and find that the hydrophobic collapse occurs in about 100 ps. We compare these results with the simulations with the plate-water van der Waals attractions turned off and with recent results on the hydrophobic collapse of multidomain proteins. Last, we discuss the relationship among the dewetting transition critical distance, van der Waals potential well depth, and water contact angle on solute surface using a simple macroscopic theory.
Dependence of adenine production upon polyamine synthesis in cultured human lymphoblasts

The exact source of de novo adenine produced by mammalian cells remain poorly understood, and this prompted the present study. Using a human lymphoblastoid cell line (WI-L2) deficient in adenine phosphoribosyltransferase (EC 2.4.2.7), we have quantitated the rate of adenine synthesis and the relative importance of the phosphorolysis of 5′-methylthioadenosine versus adenosine or 2′-deoxyadenosine in adenine generation. Dividing adenine phosporibosyltransferase-deficient WI-L2 cells produced adenine at a rate of 0.27 nmol/mg protein/h. This represented approx. 10% of the rate of hypoxanthine production by WI-L2 cells deficient in hypoxanthine phosphoribosyltransferase (EC 2.4.2.8) but was equivalent to the rate of 5′-methylthioadenosine synthesis by human lymphoblastoid CCRF-CEM cells deficient in 5′-methylthioadenosine phosphorylase (5′-methylthioadenosine: orthophosphate methylthioribosyltransferase). Up to 97% of adenine, but not hypoxanthine, synthesis was inhibited dose-dependently by the S-adenosylmethionine decarboxylase-inhibitor methylglyoxal bis(guanylhydrazone) and also by spermidine and spermine, but was enhanced by putrescine. The addition of 2-fluoroadenine, a potent competitive inhibitor of methylthioadenosine phosphorylase (Ki = 0.43 μM) to adenine phosphoribosyl-transferase-deficient cells resulted in a progressive accumulation of 5′-methylthioadenosine in the culture medium, and up to an 85% decrease in adenine production at non-toxic concentrations. These results show that de novo adenine synthesis by dividing human cells is considerable, and that 85−97% derives from the cleavage of 5′-methylthioadenosine and hence from polyamine synthesis.
Bacteriophage P22 scaffolding protein forms oligomers in solution.

Abstract The scaffolding protein of Salmonella typhimurium bacteriophage P22 is a 33.6 kDa protein required both in vivo and in vitro for the polymerization of the viral coat protein into closed T = 7 icosahedral procapsids. In vitro assembly reaction kinetics have previously been found to vary between second and third order with respect to scaffolding protein concentration, suggesting that dimers and/or higher-order oligomers may be the active species in assembly. Analytical ultracentrifugation experiments suggest that scaffolding protein undergoes a rapidly-reversible monomer/dimer/tetramer equilibrium, with higher association constants at 4°C than at 20°C. Under conditions in which in vitro assembly reactions are carried out (30 to 1000 μg/ml scaffolding protein, 20°C), monomers are the predominant species, but the concentration of dimers is significant. A mutant scaffolding protein, R74C/L177I, which forms disulfide-linked dimers, catalyzed procapsid assembly at a higher rate than did the wild-type scaffolding protein; preincubation in dithiothreitol had little effect on the wild-type protein, but greatly reduced the activity of the mutant. These findings suggest that dimers and/or higher-order oligomers of scaffolding protein are active species in the assembly of P22.
A voltammetric study of galena immersed in acetate solution at pH 4.6

The electrochemistry of galena in an acetate solution at pH 4.6 has been studied through the use of linear sweep voltammetry. Analysis of the voltammograms for anodic limits as high as 845 mV indicates that S0 is the sulphur-bearing species generated during the oxidative dissolution of galena. Furthermore, interpretation of the electrochemical data on the basis of thermodynamic considerations indicates that galena interacts with the acetate electrolyte and that Pb(CH3COO)2(aq) is also produced during anodic oxidation. When the scan direction is reversed in the cathodic direction, the oxidation products are removed by two reduction reactions when the solution is quiescent: the recombination of Pb(CH3COO)2 and S0 to form PbS and the reduction of S0 to H2S. In a stirred solution, only the second reaction is possible. Experiments conducted in the presence of 10−3 or 10−2 M lead acetate indicate that the presence of dissolved lead tends to inhibit the dissolution process. Furthermore, metallic lead can begin to deposit on the galena surface when the potential drops below about −330 mV SHE. The data also agree most closely with thermodynamics when Pb(CH3COO)2 is considered to be the aqueous species involved in the deposition and dissolution of metallic lead.
Influence of race and gender on related donor renal transplantation rates.

Abstract Racial differences in kidney transplantation have received recent attention both in the medical community and in the general public. Most efforts to improve renal transplantation among minority groups have been directed toward cadaveric donation and transplantation. Since evaluation of the comparative trends by race of living related donor (LRD) kidney transplantation have been lacking, we examined trends of LRD transplantation from 1983 through 1990 using national data from the US Renal Data System. The total number of LRDs in blacks did not change during the 8-year period between 1983 and 1990 (198 in 1983 and 197 in 1990). During this same period, the total number of LRDs in whites increased by 11% (1,390 in 1983 and 1,548 in 1990). Rates of LRD transplantation per nontransplanted dialysis patients were consistently lower in blacks and females compared with whites and males, respectively. White males have a fivefold higher rate of LRD transplantation than black males, whereas white females have a fourfold higher rate then black females. When intra racial gender differences were examined, black males were transplanted with LRD kidneys at a rate 20% higher than black females. This difference was present between 1983 and 1989, but was nonexistent in 1990. Among whites, males also had a higher rate of LRD transplantation than females, which gradually decreased from 34% in 1983 to 20% in 1990. In view of the ever-increasing demand for cadaver organs, additional effort in the medical community and society toward increasing LRD transplantation rates represents a more promising approach to increasing organ donation in all groups than a single focus on cadaveric donation. If such efforts are specifically targeted, then described racial and gender disparities in LRD transplantation are likely to be reduced.
High-frame-rate CCD imager with nonlinear charge sampling

We describe the architecture of high-frame-rate, frame-interline-transfer CCD arrays designed for optical signal processing applications. A gain-compression scheme is implemented in the pixel structure to increase the optical detection dynamic range. Simulation results are presented and compared with test results of imagers from the first fabrication lot.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Genetic control of in vitro regeneration in alfalfa (Medicago sativa L.)

The genetic control of plant regeneration from callus culture was studied in tetraploid alfalfa (Medicago sativa L.). Seven cultivars (total 72 plants) were screened for regenerability. Ladak had the best regeneration response, in which 42% of the plants regenerated. Four regenerable plants and three nonregenerable plants were used to form 10F1 hybrids and three S1 populations. Segregation ratios in the populations suggested that regenerability of alfalfa via petiole culture was under the control of two complementary genes, Rn3 and Rn4. The presence of both dominant genes was necessary for a plant to regenerate in a two-step culture system. The data also indicated that gene dosage influenced regeneration efficiency. Significant reciprocal effects demonstrated that the interaction between callus induction medium and callus regenerability was affected by cytoplasmic factor(s).
Factor adjustment implications of a Trade Promotion Agreement between the United States and Colombia

Purpose – This paper proposes to use changes in intra‐industry specialization indicators over the period 1996‐2008 to assess the potential for factor adjustment pressures that may arise in the USA if the proposed USA‐Colombia Trade Promotion Agreement (TPA) is implemented. Results show that there is considerable scope for intra‐industry specialization between Colombia and the USA. The TPA should result in a larger increase in US exports to Colombia than US imports from Colombia, because Colombian exporters face much lower tariffs in the USA market than do US exporters in the Colombian market. Given the tariff asymmetry, scope for intra‐industry specialization, the relatively large size of the US market, and the small number of US industries that are likely to encounter factor adjustment pressures, the USA should ratify the agreement immediately.Design/methodology/approach – Changes in intra‐industry specialization indicators are used to identify US industries that may face factor adjustment pressures as a...
Electro-optical signature analysis for personnel detection in urban environments

Georgia Tech has initiated a research program into the detection of covert personnel. This program focuses on the detection problem in scenarios focused on urban operations, tunnels, or convoys. These nontraditional operational scenarios present multiple opportunities for personnel to hide as well as a variety to clutter levels. The research program focuses on a detailed phenomenological analysis of human physiology and signatures with the subsequent identification and characterization of potential observables - initially in the context of urban environments. For this current effort, several electro-optical sensing modalities have been evaluated for use as a component in an unattended sensor suite designed to detect personnel. These modalities include active sensors (e.g., vibrometry) and passive sensors (e.g., multispectral, thermal). Particular emphasis has been given to the investigation of short wave infrared signatures and the comparison of this band to the other electro-optical wavebands. This paper will discuss the design of a multi-spectral signature model which forms a component of the evaluation process. Example results will be presented as well as a discussion of the issues to be addressed as part of the electro-optical sensor evaluation.
Effects of hypercapnia on blood-gas and acid-base status in the white sturgeon, Acipenser transmontanus

The effect of environmental hypercapnia on respiratory and acid-base variables was studied in white sturgeon, Acipenser transmontanus. Blood PCO2, PO2, pH, hemoglobin concentration, and plasma lactate, glucose, catecholamines and cortisol were measured first under normocapnia (water PCO2 < 0.5 Torr, 1 Torr = 133.32 Pa), then under hypercapnia (25–35 Torr) and a final return to normocapnia at 19 ± 0.5 °C. Acute (≤ 2h) hypercapnia significantly increased arterial PCO2 (8-fold increase), ventilation frequency (2-fold increase), plasma HCO3− (2.3-fold) and decreased arterial pH (to 7.15 ± 0.02). After 24 h, norepinephrine, epinephrine and cortisol, were significantly increased, and arterial pH reached its nadir (7.10 ± 0.03). During the 72- and 96-h-periods, arterial PCO2 (24 ± 4.4 Torr) and ventilatory frequency (105 ± 5 breaths min−1) stabilized, HCO3− reached its apparent maximum (23.6 ± 0.0 mmol−1), glucose decreased by 32%, and pH increased significantly to 7.31 + 0.03. The return to normocapnia completely restored arterial PCO2 (2.5 ± 0.14 Torr), HCO3− (7.4 ± 0.59 mmol · l−1), ventilation frequency (71 ± 7 breaths · min−1), and pH (7.75 ± 0.04). Overall, hypercapnia produced a respiratory acidosis, hyperventilation, a transient norepinephrine “spike”, and increased plasma catecholamines, cortisol, and arterial PO2. The respiratory acidosis was only partially compensated (35% pH restoration) 96 h after the onset of hypercapnia and resulted in a significantly decreased blood-O2 affinity (Bohr effect), as determined by construction of in vitro blood O2 equilibrium curves at 15 °C and 20 °C. Prolonged exposure to hypercapnia may lead to acid-base disturbances and negatively affect growth of white sturgeon.
Scanning electron microscopy of intraovarian embryos of the viviparous teleost, Micrometrus minimus (Gibbons), (Perciformes: Embiotocidae)

Scanning electron microscopy of the hypertrophied hindgut and spatulate expansions of the fin membrane in embryos of a viviparous surfperch Micrometrus minimus (Gibbons) has revealed evidence as to the role of these secondary embryonic adaptations in foetal-maternal exchange processes. The villified hindgut probably functions primarily in the absorption of dissolved nutrient material from ingested ovarian fluid, while the vascular spatulate expansions facilitate the respiratory exchange of gases between embryonic and maternal circulations.
Factors Influencing the Body Condition of Rainbow Trout in Small Wyoming Reservoirs

ABSTRACT Possible relations between the body condition of rainbow trout (Oncorhynchs mykiss) and the density of salmonid fishes, the abundance of non-salmonid fishes, and two measures of biological productivity—total dissolved solids and elevation above mean sea level—were assessed for 13 small (< 170 surface hectares) reservoirs in Wyoming. The mean condition of rainbow trout was positively related to total dissolved solids and negatively related to the abundance of non-salmonid fishes.
Carotenoid bioavailability from raw vegetables and a moderate amount of oil in human subjects is greatest when the majority of daily vegetables are consumed at one meal.

Abstract While the impact of food composition and processing on carotenoid bioavailability has been the subject of several investigations, the effect of meal patterning remains unknown. The aim of this pilot study was to assess the impact of select consumption patterns on the bioavailability of carotenoids from vegetables. On three randomized testing days, subjects consumed raw salad vegetables and 8 g canola oil over a two meal period in three meal patterns. Meal patterns included consumption of 100% of vegetables and oil in the first meal and 0% in the second, 75% in the first meal and 25% in the second, and 50% in the first meal and 50% in the second. Additional protein-rich "chef's salad" ingredients were distributed equally between meals. We hypothesized that carotenoid absorption would be highest when 50% of vegetables and oil were consumed at each meal and lowest when 100% were consumed at once. Blood was collected 0 to 12 hours postprandially and triacylglycerol-rich lipoprotein fractions (TRL) were isolated by ultracentrifugation. TRL carotenoid concentrations were analyzed by high performance liquid chromatography–diode array detector. Considering all carotenoids, absorption expressed as area under the curve was greatest when ≥75% of vegetables were consumed in a single meal ( P P P
Fetal supply of amino acids and amino nitrogen after maternal infusion of amino acids in pregnant sheep

Abstract Objective: The objective of the study was to determine whether a prolonged maternal infusion of amino acids would increase the umbilical uptake of amino acids and uteroplacental ammonia production. Study Design: Six pregnant sheep (134.5 ± 2.3 days after conception) were infused for 12 hours overnight with an amino acid solution. Uterine and umbilical blood flows were measured with the ethanol steady-state diffusion technique before (control) and during (experimental) infusion. Plasma amino acid and whole-blood ammonia concentrations were measured. Results: After infusion, despite an increase in maternal arterial amino acid concentration, umbilical uptakes increased significantly only for branched-chain amino acids. Fetal ammonia concentrations and uteroplacental ammonia production increased moderately. Fetal nitrogen supply did not increase. Uterine nitrogen uptake represented 36% of the maternal nitrogen intake in the control period and 14% in the experimental period. Conclusion: Prolonged maternal infusion of an amino acid solution was a relatively ineffective method of increasing fetal amino acid supply. (Am J Obstet Gynecol 1999;180:447-53.)
Workers Versus Firms: Bargaining Over a Firm's Value

We introduce a distinction between a firm and its network of workers. In a competitive world, if networks are easily lured away, the workers must receive the entire value of their contribution to the firm. How then can service firms have equity value? A model is analysed in which workers are paid less as a group than their value, even in a competitive world. The workers are assumed to have a nonwage benefit for working at the current firm; this benefit is privately known. These privately known benefits make it impossible for the workers to agree on a division of their value should they leave the existing firm for a new enterprise. The result is that the workers may receive a total compensation that is less than their contribution to the firm.
Habituation and Dishabituation in the Absence of a Central Nervous System

Habituation and dishabituation have been observed in a semi-intact Aplysia preparation in which the central nervous system is removed. The amplitude of withdrawal responses in the gill decreases in proportion to the rate of water drops applied (one drop per 0.5 minute to one drop per 2.5 minutes at 15°C). The effects of habituation last for at least 2 hours. A dishabituated response is elicited by stopping the water drops or electrically stimulating the preparation. Furthermore, the gill contains nerve cell bodies, and habituation and dishabituation appear to be properties of these peripheral neurons.
Improved care and growth outcomes by using hybrid humidified incubators in very preterm infants.

OBJECTIVE: To identify changes in temperature, fluid and electrolyte management, growth, and short-term outcome in extremely low birth weight (ELBW) infants nursed in humidified hybrid incubators (HI group) compared with a cohort of patients cared for in nonhumidified conventional incubators (CI group). METHODS: Body temperature (BT), fluid and electrolyte balance, and growth velocity (GV) were collected retrospectively on 182 ELBW infants. The CI group included ELBW infants cared for with radiant warmers followed by an incubator without humidity. The HI group included ELBW infants cared for in the radiant warmer mode in a Giraffe OmniBed, followed by the incubator mode using high humidity. RESULTS: The CI group included more multiple births (50.6%) than the HI group (35.8%; P CONCLUSIONS: Use of a humidified hybrid incubator improved care for ELBW infants by making it possible to decrease fluid intake, improve electrolyte balance, and enhance GV without a disturbance of BT compared with conventional care. By adjusting fluid intake when using these devices, benefits may be enhanced and the risk of BPD and severe BPD may be reduced.
The Millennium Arecibo 21 Centimeter Absorption-Line Survey. IV. Statistics of Magnetic Field, Column Density, and Turbulence

We discuss observations of the magnetic field, column density, and turbulence in the cold neutral medium (CNM). The observed quantities are only indirectly related to the intrinsic astronomical ones. We relate the observed and intrinsic quantities by relating their univariate and bivariate probability distribution functions (pdf's). We find that observations of the line-of-sight component of a magnetic field do not constrain the pdf of the total field Btot very well but do constrain the median value of Btot. In the CNM, we find a well-defined median magnetic field 6.0 ± 1.8 μG. The CNM magnetic field dominates thermal motions. Turbulence and magnetism are in approximate equipartition. We find that the probability distribution of column density N⊥(H ) in the sheets closely follows N⊥(H )-1 over a range of 2 orders of magnitude, 0.026 N⊥(H ) 2.6 × 1020 cm-2. The bivariate distributions are not well enough determined to constrain structural models of CNM sheets.
Accuracy of Pedicle Screw Placement in Children 10 Years or Younger Using Navigation and Intraoperative CT.

STUDY DESIGN A consecutive case series. OBJECTIVE To determine the revision rate for pedicle screws placed using intraoperative CT and image-guided navigation in children 10 years or younger. SUMMARY OF BACKGROUND DATA Screws are frequently used for spinal instrumentation in young children, although this is only by physician-directed use. This is a multicenter retrospective study of patients aged 10 years or younger, who underwent spinal screw instrumentation with image-guided navigation. We hypothesized that intraoperative navigation would result in a high rate of accuracy for screw placement. METHODS Between 2007 and 2013, 130 pedicle and 7 lateral mass screws were placed in 16 consecutive patients undergoing a total of 17 surgeries at 2 institutions. Mean age at surgery was 6.9 years (range, 0.8-10.9 y). Screws were placed using an open technique with intraoperative CT (O-arm) and image-guided navigation (Stealth). Procedures included: growing spine device (3), hemivertebrae excision (4), posterior fusion (7), cervical fusion (2), and vertebral column resection (1). Congenital deformity was the most common diagnosis. Primary outcome measures were need for intraoperative screw revision or complication associated with screw placement. RESULTS Mean number of screws used per procedure was 8.1 (range, 2-17). Screws were placed from C1 to L5. Of the 137 screws, 3 required revision to shorter screws for an overall accuracy rate of 97.8%. In 1 case, a right T3 screw was revised due to anterior penetration. In another case, left-sided T1 and T2 pedicle screws were shortened 5 mm because they had penetrated the anterior aspect of their respective vertebral bodies. There were no screw-related complications. CONCLUSIONS In this series, image-guided navigation resulted in accurate placement of screws in patients aged 10 years or younger with no associated intraoperative complications. The navigated accuracy rate (97.8%) is significantly higher (P=0.01) than the reported 90.9% pedicle screw accuracy rate without navigation in the same age group by Baghdadi and colleagues. Intraoperative CT and image guidance were useful in our practice for placement of screws in skeletally immature patients.
Group Dynamics and Attitude-Behavior Relations

A model is presented in which attitudes have effects on behaviors, behaviors are compared against norms to define deviance, and deviance has a return, corrective effect on attitudes through mechanisms of social control. Social interactions link these individual processes to form a single interpersonal system within a group. It is demonstrated that in a system of this kind, an attitude-behavior correlation is a function of many different social psychological effects, and its value conceivably could be positive, zero, or even negative. Results of a preliminary empirical study using two-stage least squares to estimate system parameters show that the proposed system is viable with some modifications. In particular, empirical evidence in support of an attitude-behavior effect is found.
Comparison of electroencephalographs of young rats from dams on synthetic and on normal diets.

croscopy are mounted dry on albumin-coated slides to avoid destruction of some of the enzyme which occurs when water is used to flatten paraffin sections). The enzymatically liberated phosphate is converted to the lead salt, and the usual treatment with ammonium sulfide and careful rinsing with water follows. It is necessary to substitute lead for the cobalt of the alkaline phosphatase procedure, since cobalt sulfide is insufficiently soluble in the HCl required subsequently.
Simulation of full Earth disk measurement at L-1 of reflected solar radiation

The Triana spacecraft will be launched into a halo orbit around L-1, the first Lagrangian point, in late 2000. It will carry an active cavity radiometer for measuring outgoing longwave and reflected solar irradiance from the full disc of the Earth. The reflected solar radiation case is complex and requires computer simulation. The elements of the simulation are described. The purpose of the simulation is to develop a quantitative understanding of the effects of various factors on the measurements to aid in their interpretation. These factors include the variation of albedo over the Earth- atmosphere system, changes of albedo with solar zenith angle and anisotropy of the reflected solar radiation. Finally, there is a diurnal cycle of regional albedo due to clouds varying daily. The active cavity radiometer will also be very useful as a calibration standard for high spatial resolution results from the Earth Polychromatic Imaging Camera (EPIC). The EPIC will provide 10 km resolution imagery every 15 minutes over the Sun-lit face of the Earth, providing information at mesoscale space and time resolution about ozone, aerosols, water vapor and clouds.
The CFTR gene: male infertility and assisted conception

Approximately 30–40% of couples seeking fertility treatments have male factor infertility. Their dysfunctions include azoospermia, oligozoospermia, asthenozoospermia and teratozoospermia. Those with azoospermia represent about 25% of the total, and of these about 30% have an obstructive process while the remaining have either primary or secondary testicular failure. In the obstructive azoospermia group, 25% of males have congenital bilateral absence of the vas deferens (CBAVD).
Mammographic Computer-Assisted Diagnosis using Computational Statistics Pattern Recognition

Abstract Research begun for target identification utilizing pattern recognition has been applied to mammographic computer-assisted diagnosis. The research has utilized the discipline of computational statistics. Feature extraction based on fractals and incorporating segmentation boundaries led to probability density estimation and classification based on discriminant analysis. The results of applying these techniques to mammography are very promising and are reported herein. The results of these limited mammographic studies are discussed in their own light and in comparison with other's work.
Subwavelength visualization of light in thin film waveguides with photoelectrons

We report the visualization and quantitative analysis of electromagnetic surface fields at solid surfaces with the potential for \ensuremath{\lambda}/50 resolution. To illustrate this capability, we investigate patterns in two-photon photoemission images of light-diffracting structures in waveguiding, transparent thin films. The obtained micrographs show interference patterns between incident and guided light with a remarkable sensitivity to subwavelength features. We demonstrate that photoemission rates are directly related to the surface field strengths and develop a subwavelength method to calculate the surface fields from optical properties and surface topology based on the two-dimensional Kirchhoff diffraction integral. Calculated images based on this theoretical approach compare favorably to experimental electron micrographs.
Clutter forecast - a synthesis of mesoscale numerical weather prediction and empirical site specific radar clutter models

This paper introduces a new model approach that derives three-dimensional refractivity profiles from mesoscale numerical weather prediction (MSNWP), applies them to parabolic equation propagation models, and combines them with empirical surface clutter reflectivity to generate a more realistic model of surface clutter. Realistic site specific clutter models must be faithful to the energy propagation to the surfaces that are responsible for the return clutter power; it is not good enough to maintain validated databases of reflectivities, however important that empirical data might be. This synthesis of MSNWP and radar clutter models can provide clutter and propagation forecasts to military planners, retroactive prediction of propagation for clutter test data analysis, and realistic models for radar system design and performance analysis.
Elements of General, Organic, and Biological Chemistry, Ninth Edition (Holum, John R.)

John R. Holum. Wiley: New York, NY, 1995. xvi + 605 pp. Figs., tables, and photos. 21.3 X 26.3 cm. $64.95.The ninth edition of Holum's textbook continues to be a shortened version of his Fundamentals of General, Organic, and Biological Chemistry, Fifth edition (1994). It incorporates the changes and improvements made in that text. The audience for this text includes students in the health sciences (other than physicians) and nonscience students with an interest in the molecular nature of matter. The text can be used for a one-term course and does not have any chemistry prerequisites. The author has striven to create the most up-to-date kind of text possible particularly in environmental studies and the molecular basis of life.Chapters are organized, as in the past editions, into general chemistry topics (1-8), the organic chemistry essential for biochemistry (9-13), and biochemistry (14-21). Radioactivity and nuclear chemistry are the topics of the final chapter. Changes made in this edition include a rev...
Electrochemical development of particle tracks in CR-39 polymer dosimeters

Abstract Electrochemical etching of CR-39 polymeric track etch neutron detectors results in proton-recoil tracks which can be distinguished from background tracks much better than tracks developed solely by chemical etching. A newly designed and constructed electrochemical etching apparatus allows large numbers of dosimeters to be processed simultaneously with consistent results. Many processing systems have been developed for chemical and electrochemical etching of the track etch dosimeters. Three systems specifically show great promise and are being studied extensively.
Noise sources and optoelectronics which affect axial detection performance of time domain, Fourier domain, and swept source optical coherence tomography

Techniques based on spectral interferometry (SD-OCT) have recently been examined, with authors often suggesting superior performance compared to time domain optical coherence tomography (TD-OCT) techniques. While these technologies have similar resolutions and the spectral techniques may currently claim faster acquisition rates, their detection parameters may be inferior. This work examines the theoretical signal to noise ratio and dynamic range of these techniques including time domain. Considering the practical limits of optoelectronics, the often ignored or misunderstood factors which affect performance, such as vacuum fluctuations, the actual source of thermal noise, excess noise and A/D conversion losses, were taken into account. Methods for potentially improving signal to noise ratio (SNR), such as fast laser sweeping with high laser intensities and CCD integration, were evaluated as well. This is critical because dynamic range translates directly into imaging depth. The technologies are compared relative to the differences in these parameters. While Fourier domain OCT (FD-OCT) has some advantages such as signal integration, it appears unlikely that its disadvantages can ultimately be overcome. Ultimately, time TD-OCT appears to have the superior performance with respect to SNR and dynamic range. However certain positive aspects of swept source OCT (SS-OCT) leave open the possibility that its performance may approach that of TD-OCT.
Synchronization of Aedes albopictus mosquito cells using hydroxyurea

We have established conditions for use of hydroxyurea, a reversible inhibitor of DNA synthesis, to synchronize the division cycle of a continuous cell line from the mosquito, Aedes albopictus. In the range of 0.15-0.25 mM hydroxyurea, an 18 h treatment, followed by removal of the drug, results in effective synchronization. When combined with the partial synchronization that occurs within 10 h of dilution and plating, more than 80% of cells treated with hydroxyurea could be recovered in the synthesis (S) phase of the cell cycle during the 4 h period after removal of the drug. The degree of synchrony was enhanced when cells were exposed to two consecutive hydroxyurea treatments spaced 10 h apart. Synchronized cells expressed maximal levels of a reporter gene when transfected immediately after removal of hydroxyurea. This is the first description of effective chemical synchronization of an insect cell line using hydroxyurea.
Nitrogen-Use Efficiency among Flue-Cured Tobacco Genotypes

Today's flue-cured tobacco (Nicotiana tabacum L.) cultivars differ significantly in yield and quality from cultivars grown early in the 20th century. One major change in crop management has been an increase in fertilizer use, especially N. In view of the changing fertilization pratices and the current importance of N in crop production, this study was initiated to evaluate genetic variability in N-use efficiency in flue-cured tobacco
The role of calcium in supersensitivity to the inotropic effects of norepinephrine

Experiments using electrically stimulated rabbit left atria have demonstrated that supersensitivity to the inotropic effects of norepinephrine can be induced by either chronic reserpine pretreatment or hypothermia (lowering the temperature of the bathing medium). These two experimental conditions for inducing supersensitivity were not additive implying that they shared a common mechanism of action. Norepinephrine had no significant effect on the amplitude of a potentiated contraction of the rabbit atrium when the temperature was reduced from 37 to 30°C or following pretreatment with reserpine (30 or 37°C). Under these same conditions the ED50 of norepinephrine on the normal contraction was reduced. It is concluded that both reserpine pretreatment and hypothermia induced supersensitivity to the inotropic effects of norepinephrine by enhancing the cellular store of activator calcium while not affecting the ability of norepinephrine to release activator calcium.
Assessment of Compliance with Lipid Guidelines in an Academic Medical Center

Background:The importance of achieving a low-density lipoprotein cholesterol (LDL-C) level less than 100 mg/dL in patients with coronary artery disease (CAD) or cerebrovascular disease (CVD) is well established. Emerging evidence supports the recognition and management of secondary lipid goals, high-density lipoprotein cholesterol (HDL-C) level greater than 40 mg/dL, and triglyceride level less than 150 mg/dL.Objective:To evaluate whether inpatient services within an academic setting were achieving/addressing primary and secondary lipid goals in patients with established CAD or CVD.Methods:Patients with a discharge diagnosis of acute myocardial infarction, myocardial revascularization procedures, and/or ischemic stroke were identified. A retrospective chart review was done to assess adherence to the American Heart Association (AHA)/American College of Cardiology (ACC) guidelines for lipid management.Results:On average, 63% of patients with CAD or CVD had a lipid panel assessed during their hospitalization...
The relationship between meniscal tears and meniscal position

Objective: To investigate how different types of meniscal tears predispose to different patterns of meniscal position in subjects with and without symptomatic knee osteoarthritis (OA). Methods: A cross-sectional analysis of 161 women participating in an observational study to evaluate knee OA progression was performed using baseline MRI data. Meniscal morphologic features were scored in three separate locations. Meniscal position measures were determined for extrusion and proportion of coverage. Analysis was performed using multiple linear regression models treating each tear type as an individual variable with a binary response. Results: Complex tears, cysts and maceration of the medial meniscus were associated with more medial (p=0.0004, p=0.004, p <0.0001, respectively) and anterior extrusion (p =0.03, p=0.03, p<0.0001, respectively) than normal menisci. Horizontal tears of the lateral meniscus had more lateral (p=0.005) and anterior extrusion (p<0.0001) than normal menisci. Anterior and body tears of the medial meniscus were associated with more anterior extrusion (p=0.0006, p=0.01, respectively), whereas meniscal body tears alone had more medial extrusion than normal menisci (p= 0.0002). Meniscal body tears of the lateral meniscus had more lateral extrusion than normal menisci (p=0.01). Conclusion: Anterior horn and meniscal body tears and the more severe macerated and complex tear types predisposed to more medial meniscal extrusion. Laterally, only meniscal body and horizontal tears significantly affected extrusion, potentially reflecting a lower overall prevalence of lateral meniscal tears. These results may have important implications in identifying tear types associated with more meniscal dysfunction, with the ultimate goal of identifying those at greatest risk for knee OA progression.
Tyr-MIF-1 binding in brain is not altered by ligands selective for the GABAA/benzodiazepine receptor.

Abstract Binding of benzodiazepines to the benzodiazepine γ-aminobutyric acid (GABA) receptor-chloride channel complex has been shown to be altered by Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH 2 ). This raised the possibility of allosteric binding interactions between Tyr-MIF-1 sites and the GABA A receptor complex. We tested this possibility in rat brain by examining the binding of Tyr-MIF-1 to brain membranes in the presence of clonazepam, GABA, a combination of clonazepam and GABA, RO15788, or picrotoxinin. None of the tested substances affected Tyr-MIF-1 binding. We also tested mouse cortex for changes in Tyr-MIF-1 binding in the presence of ligands that bind to the GABA/benzodiazepine/chloride channel complex. Clonazepam, flunitrazepam, RO15788, and picrotoxinin at concentrations ranging from 10 −13 to 10 −5 M, each in the absence or presence of GABA at concentrations ranging from 10 −9 to 10 −6 M, did not significantly alter the binding of Tyr-MIF-1. The results indicate that simple bidirectional allosteric interactions between Tyr-MIF-1 binding sites and benzodiazepine, GABA or chloride channel binding sites are not likely to be the mechanism by which Tyr-MIF-1 affects binding at this complex.
Atrial fibrillation is common after ablation of isolated atrial flutter during long-term follow-up

Background Previous studies have shown that the incidence of atrial fibrillation after atrial flutter ablation is approximately 20% among patients presenting with typical atrial flutter and no history of fibrillation. However, studies involving this population have been small, with follow-up typically less than 2 years. Objective The purpose of this study was to provide a more accurate perspective on the long-term risk of atrial fibrillation in patients presenting with isolated typical flutter. Methods Clinical records of consecutive patients who had flutter ablations at Presbyterian Medical Center between 1999 and 2004 were assessed (n = 254). Patients with no apparent history of atrial fibrillation before their flutter ablation were identified. Retrospective follow-up data on these patients were obtained by review of medical records from our institution, from patients' cardiologists and primary care physicians, and by direct patient questionnaires. Postablation atrial fibrillation and other arrhythmias were identified by electrocardiography, Holter monitoring, and subsequent clinical records. Results Postablation atrial fibrillation was identified in 40 (50%) of 80 patients, and an additional three patients presented with atypical atrial flutter, after a mean follow-up of 29.6 ± 21.7 months. The incidence of atrial fibrillation was progressive, with 49% occurring after 2 years. There was no difference in age, left atrial size, hypertension, structural heart disease, or left ventricular dysfunction in patients who developed atrial fibrillation compared with those who did not. Conclusion Atrial fibrillation occurs in over half of patients who present with isolated typical flutter after cavotricuspid isthmus ablation. Asymptomatic patients should be screened for recurrent arrhythmias indefinitely after ablation. In certain patients, atrial fibrillation and flutter may be different expressions of the same electrical disease, and eradication of the flutter circuit will not prevent the eventual manifestation of atrial fibrillation.
Representation of the Main Geomagnetic Field

United States representatives were active in the IAGA (International Association of Geomagnetism and Aeronomy) Commission 2 Working Group No. 4 ‘Analysis of the Geomagnetic Field,’ an international group that recommended a reference field for the main geomagnetic field. U.S. members were J. C. Cain, P. F. Fougere, F. T. Heuring, L. Hurwitz, A. B. Kahle, J. F. McClay, and A. J. Zmuda (reporter); U.S. consultants were L. R. Alldredge, D. G. Knapp, J. H. Nelson, and E. H. Vestine.
"Does Open Innovation Help New Technology-Based Firms, located in Isolated Areas?"

Focusing on the access to knowledge, this study attempts to provide a validation of open innovation (OI) for firms located in areas lacking positive externality from industrial agglomeration, by fo...
Antidepressant medication change in a clinical treatment setting: a comparison of the effectiveness of selective serotonin reuptake inhibitors.

Background: This investigation focuses on the 3 most frequently used selective serotonin reuptake inhibitors (SSRIs) (paroxetine, fluoxetine, sertraline) and examines the rate of medication switches as a measure of effectiveness. We answer 2 questions: (1) What is the likelihood that a patient starting treatment with an SSRI will complete treatment with the same agent? and (2) Depending on the initial SSRI agent used, do patients switch at different frequencies? Method: A retrospective chart review was performed on 2779 patients treated in a university outpatient clinic from March 1995 to January 1997. Of these, 263 patients given antidepressants were randomly selected: 214 were prescribed SSRIs; 24, novel antidepressants; and 25, tricyclic antidepressants. Results: There was no significant difference in rate of switching between the different classes of antidepressant (p =. 1) nor between drugs within the SSRI class (p = .513). When medication change was the independent factor, significant differences between the groups were total time in treatment and number of visits (p <.001 and p =.011, respectively). Age, education, and Clinical Global Impressions-Severity of Illness scale scores (admission, discharge, and change) were not significantly different between the groups. Conclusion: Approximately 25% of patients started with an SSRI will switch to another antidepressant in the course of their treatment. The SSRIs appear to be equivalent in effectiveness. They are not interchangeable, because patients who discontinue one SSRI for lack of tolerability or response can generally be treated effectively with another.