cssi/SciSciGPT-SciSciNet huggingface dataset:
Gain and efficiency studies of a high-power traveling-wave-tube amplifier

The results of measurements on the gain and efficiency of a high power travelling wave tube amplifier powered by a 850 keV, 0.8-1.6 kA, 100 nsec pencil electron beam are reported. The amplifier operates in the TM01 mode and is driven by a 250 kW magnetron. Gains of up to 35 dB and efficiencies of 11 percent have been achieved in a single stage amplifier with a power output of about 100 MW. Increases in the gain beyond 35 dB result in a driven oscillation due to positive feedback from a small impedance mismatch at the output. A two stage severed amplifier has also been developed to prevent the driven oscillation. Preliminary results indicate that the severed amplifier has a peak power output of 400 MW and an efficiency of over 40 percent.
Generalized Laurent polynomial rings as quantum projective 3-spaces

Abstract Given a ring R , we introduce the notion of a generalized Laurent polynomial ring over R . This class includes the generalized Weyl algebras. We show that these rings inherit many properties from the ground ring R . This construction is then used to create two new families of quadratic global dimension four Artin–Schelter regular algebras. We show that in most cases the second family has a finite point scheme and a defining automorphism of finite order. Nonetheless, a generic algebra in this family is not finite over its center.
Understanding the Nature of the DNA-Assisted Separation of Single-Walled Carbon Nanotubes Using Fluorescence and Raman Spectroscopy

Certain DNA sequences form a highly stable monolayer at the surface of single-walled carbon nanotubes, enabling their dispersion in aqueous solution. Ion-exchange chromatography can be used to separate these systems on the basis of their diameter in distinct, eluted fractions. Raman and fluorescence spectroscopy are used to characterize the nature of the separation by a comparison of radial breathing mode intensities at 457-, 532-, 633-, and 785-nm excitation wavelengths. Trends reveal a strong diameter dependence of the fractions, with larger diameters eluting later than smaller diameters. Average diameters of each fraction varied from 0.816 and 1.084 nm for the first and last eluted fractions, respectively. This conclusion is supported by a systematic shifting of the Raman tangential mode with increasing elution as well as changes in the relative intensities of radial breathing modes. Fluorescence emission from each fraction reveals the absence of relative shifting or broadening and hence uniformity in ...
Effects of an aquatic plant and suspended clay on the activity of fish toxicants

Abstract Rotenone, antimycin, permethrin, pydrin, and Salicylanilide I were tested for their toxicities against fathead minnows (Pimephales promelas) in the presence of Canadian waterweed (Elodea canadensis) or suspended clay. The plants had little effect on the activity of rotenone and antimycin but substantially reduced the activity of permethrin and pydrin (synthetic pyrethroids). Bentonite severely inhibited the activity of all chemicals tested. Salicylanilide I was affected least and pydrin most (27 times as much pydrin was required when I g/liter of bentonite was present in 96-hour tests). The efficacy of the registered fish toxicants rotenone and antimycin is probably not significantly affected by vegetation under field conditions, but is greatly reduced by suspended bentonite clay.
Gender differences in response to ambient color, task complexity and presence of evaluative others

Sixty-four male and thirty-two female subjects each performed a CRT pursuit tracking task in one of the eight conditions created by combinations of task difficulty (simple versus complex), evaluative audience presence versus absence, and wall color (red versus green). Females recorded significantly higher error scores, were less aroused and more sensitive to ambient color than were their male counterparts. Further, audience presence was found to enhance male and impair female tracking performance. Results suggest that differentials in subject motivation may have affected the present research.
Model for ferric sulfate leaching of copper ores containing a variety of sulfide minerals: Part I. Modeling uniform size ore fragments

A computer model was constructed for bacterial ferric sulfate leaching of the major sulfides found in porphyry copper deposits. Leaching occurs by reactions with ferric ion diffusing into the rock fragment. The model incorporates the reaction kinetics of the individual minerals and keeps material and energy balances. The model is needed to aid in the design of modifiedin situ leaching operations and combines desirable features found in previous models with extensions needed for the described study ofin situ leaching. In modeling the leaching of single ore fragments, it is shown that the rate of ferric ion generation by bacteria can limit the rate of copper recovery. The transition from kinetic to diffusion rate limitation is different for each mineral and ore fragment size. The width of the leaching reaction zone is different for each mineral, and many reaction zones cannot be considered narrow. Minerals do not leach in proportion to their concentration in ore fragments.
Explicit solutions to an optimal portfolio choice problem with stochastic income

Abstract This paper solves in closed form the optimal portfolio choice problem for an investor with negative exponential utility over terminal wealth facing imperfectly hedgeable stochastic income. The returns on income and the stock are imperfectly correlated, so the market is incomplete. We identify how an investor adjusts their [Merton, Rev. Econ. Statist. 51 (1969) 247] portfolio of the stock and riskless asset via an intertemporal hedging demand, in reaction to the stochastic income. Under general assumptions on the process governing the income, the sign of the hedging demand is the opposite of the sign of the correlation between the income and stock. The optimal portfolio in the stock is long stock if the risk premium is positive and correlation negative, and short if these signs are reversed. Specializing in turn to normally distributed income and lognormally distributed income with or without mean-reversion, the effect of a number of parameters on the optimal portfolio in the stock can be studied. When the risk premium on the stock and correlation have opposite signs, the optimal portfolio decreases in magnitude with risk aversion, unhedgeable variance of income and time, and increases in magnitude with the magnitude of correlation under both the lognormal (without mean-reversion) and normal models for income. These relationships do not necessarily hold if the signs on the risk premium and correlation are the same, in particular the optimal portfolio is not necessarily monotone in risk aversion, violating well-known static results in models without income. When income follows a lognormal model with mean-reversion, more complicated behavior can occur. For instance, the optimal portfolio does not have to be monotonic in time, regardless of the signs of correlation and the risk premium.
Spatial hole burning and optical power in a quantum dot laser

Emission of higher-order modes caused by spatial hole burning in a quantum dot (QD) laser is studied. The critical tolerable values of the structure parameters are discussed beyond which higher-order longitudinal modes can not oscillate. The higher the mode order, the narrower the range of allowed QD-size scatter for lasing of the mode. The higher the mode order, the denser the QD-ensemble and the longer the cavity should be for lasing of the mode. The output powers of the lasing modes are calculated versus the injection-current density from the solution of the rate equations.
Sixteen Computer Programs for Statistical and Psychometric Transformations

This article describes a program, written in BASICA for DOS-based computers, for computing 16 different statistical and psychometric transformations of input data. Several types of transformations are included: those designed for changing data to meet the assumptions underlying parametric statistical procedures, those designed to facilitate the scoring of tests and inventories, and those for converting scores to norms or grades.
Polydipsia-Induced Alcohol Dependency in Rats: A Reexamination

Seven Holtzman rats were kept on a polydipsia-induced schedule of alcohol consumption for 3 months in a replication of a 1972 study by Falk and colleagues. Contrary to their results, there was no evidence of alcoholism.
Modulation of hydrophobic interactions in denatured whey proteins by transglutaminase enzyme

Abstract The role of enzyme crosslinking in mediating formation of hydrophobic association in chemically denatured whey protein isolates (WPI) is examined. WPI samples denatured with dithiothreitol (DTT) and incubated at 50 °C with and without transglutaminase enzyme show dramatic differences in viscosity, with the viscosity of the sample exposed to enzyme being lower by several orders of magnitude than the sample without enzyme. Upon further exposure of both samples to sodium dodecyl sulfate (SDS) to eliminate hydrophobic interactions, we observe no change in the viscosity of the sample previously treated with enzyme, suggesting this sample to have minimal hydrophobic associations. In contrast, the sample without enzyme shows a dramatic drop in viscosity indicating it to have had substantial hydrophobic associations. A similar trend but to a lesser extent is observed at a higher WPI concentration. These results taken together suggest that the formation of enzyme catalyzed e-(γ-glutamyl)lysine bonds attenuates hydrophobic interactions through steric hindrance and formation of compact molecules that limits exposure of the hydrophobic moieties.
Acceptance of the HPV vaccine for adolescent girls: analysis of state-added questions from the BRFSS.

Purpose: Previous research regarding human papillomavirus (HPV) awareness and vaccine acceptance has relied on convenience or other selected samples of the population. To assess the prevalence of HPV awareness and vaccine acceptance in Kentucky we added questions to the 2006 Kentucky Behavioral Risk Factor Survey System (BRFSS), a population-based survey of health behaviors. Methods: Women who participated in the statewide BRFSS were asked two HPV-related questions: one assessed previous awareness of HPV, and another assessed vaccine acceptance for girls 10 to 15 years old. We used crosstabulations and multivariate logistic regression to determine which factors were associated with HPV awareness and vaccine acceptance. Because the HPV vaccine Gardasil was approved in June 2006, we conducted an analysis of pre- and postapproval HPV awareness and vaccine acceptance. We also compared results across Appalachian and non-Appalachian counties, two distinct regions of Kentucky. Results: Overall, 57.6% of women had heard of HPV, and 70.2% accepted vaccination for girls. HPV awareness increased after Gardasil’s approval, but the increase was much smaller among Appalachian women. Prevalence of vaccine acceptance was unchanged in both regions. Awareness of HPV was not associated with vaccine acceptance, and factors significantly associated with vaccine acceptance in multivariate analysis differed by Appalachian status. Conclusions: This population-based survey of Kentucky women found relatively high vaccine acceptance for girls. Also, many respondents reported not knowing whether they accept vaccination, and factors associated with vaccine acceptance varied by Appalachian status. These findings suggest that acceptance of the HPV vaccine for girls may improve with targeted interventions. 2009 Society for Adolescent Medicine. All rights reserved.
Visual Attention to Antismoking PSAs: Smoking Cues Versus Other Attention-Grabbing Features.

This study examines how addicted smokers attend visually to smoking-related public service announcements (PSAs) in adults smokers. Smokers’ onscreen visual fixation is an indicator of cognitive resources allocated to visual attention. Characteristic of individuals with addictive tendencies, smokers are expected to be appetitively activated by images of their addiction—specifically smoking cues. At the same time, these cues are embedded in messages that associate avoidance responses with these appetitive cues, potentially inducing avoidance of PSA processing. Findings suggest that segments of PSAs that contain smoking cues are processed similarly to segments that contain complex stimuli (operationalized in this case as high in information introduced) and that visual attention is aligned with smoking cues on the screen.
Calibration of a single-mode polymer optical fiber large-strain sensor

We calibrate the phase shift as a function of applied displacement in a polymethylmethacrylate (PMMA) single-mode optical fiber interferometer, operating at a wavelength of 632.8 nm. The phase sensitivity is measured up to 15.8% nominal strain in the fiber. The measured phase–displacement response is compared to a previous analytical formulation for the large deformation response of the polymer optical fiber strain sensor. The formulation includes both the finite deformation of the optical fiber and nonlinear strain-optic effects at large deformations. Using previously measured values for the linear and nonlinear mechanical response of the fiber, the nonlinear strain-optic effects are calibrated from the current experimental data. This calibration demonstrates that the nonlinearities in the strain-optic effect are of the same order of magnitude as those in the mechanical response of the PMMA optical fiber sensor.
Use of Radiation and/or Hyperthermia for Treatment of Mast Cell Tumors and Lymphosarcoma in Dogs

Radiation alone can be used to treat mast cell tumors that are not likely to metastasize (that is, differentiated or localized lymphorecticular tumors). In patients with mast cell tumors that are likely to metastasize (that is, undifferentiated, metastatic mast cell disease or generalized lymphoreticular neoplasms), radiation should not be used as the only treatment agent. In these patients, treatment combinations of hyperthermia/chemotherapy and radiation/hyperthermia/chemotherapy have been shown to have promise, but these treatment combinations need to be evaluated in prospective trials.
Democratic Organizations for Social Change: Latin American Christian Base Communities and Literacy Campaigns

Democratic Organizations for Social Change: Latin American Christian Base Communities and Literacy Campaigns Johannes P. Van Vugt. New York: Bergin and Garvey, 1991. xviii + 174 pp. $45.00 (cloth). ISBN 0–89789–245–3.
A3-5: Research-Operations Partnerships to Improve the Quality and Affordability of Care

Background/Aims A learning health care organization requires visionary leadership to achieve the triple aim of better health, better care, and improved affordability. Effective research-operations partnerships (ROPs) can facilitate improvement efforts. Although ROPs are not novel, the process of establishing sustainable collaborations and overcoming challenges to achieve shared objectives is not well described.
Investigating adsorption of bovine serum albumin on cellulosic substrates using magnetic resonance imaging

Cellulosic biomass is recalcitrant to enzymatic hydrolysis which greatly reduces the efficiency of biofuels production. Specifically, the lignin component of biomass is thought to provide non-productive binding sites for glycosyl hydrolases, effectively disabling the enzymes from completing further digestion. A thorough understanding of the adsorption rates of protein molecules on celluloses—especially lignocelluloses—is crucial to improving the cyclic steps of adsorption, diffusion, and reaction. We use magnetic resonance imaging (MRI) to detect concentrations of bovine serum albumin (BSA) in equilibrium with various cellulose substrates, including delignified and acid-treated lignocellulosic substrates. BSA is believed to be an effective adsorption blocker during enzymatic hydrolysis of lignocellulosics, and has been correlated with an increase in reaction yield. We found BSA to have little adsorption onto the chosen cellulose substrates in the low concentration range studied. Ultraviolet (UV) absorption measurements of reaction supernatants at 280 nm were used to confirm the MRI results for each of the substrate types. The advantages of the MRI technique are compared with that of the traditional UV measurement.
Characterization of SH acoustic plate mode liquid sensors

Abstract Two-port acoustic wave sensors have been fabricated, which utilize shear horizontal (SH) acoustic plate modes (APMs) to probe a solid/liquid interface. These modes, excited and detected by interdigital transducers on thinned quartz plates, propagate efficiently with liquid contacting the device and allow sensing to be performed on the side of the device opposite the transducers. A number of sensing mechanisms have been discovered, including mass loading, viscous entrainment of the contacting liquid, and acoustoelectric coupling between evanescent plate mode electric fields and ions and dipoles in solution. The mass sensitivity of the APM device enables it to function as a microbalance in a number of sensing applications. A chemical sensor capable of detecting low concentrations of Cu 2+ ions in solution has been constructed by chemically modifying the device surface with ethylenediamine ligands. The treated devices bind Cu 2+ ions in a manner that can be reversed by the addition of acid to the solution.
Exploring the Utility of Self-Control Theory for Risky Behavior and Minor Delinquency Among Chinese Adolescents

Although scholarly interest in empirically assessing Gottfredson and Hirschi’s (1990) self-control theory continues to grow, there is little research available on evaluating its utility in China. T...
Mediastinal infection after cardiac surgery

Mediastinitis is an uncommon complication after cardiac surgery; however, its associated morbidity and mortality demand early recognition and emergency therapy. This review is intended to emphasize certain features of the incidence, pathogenesis, and bacteriology of this complication in patients undergoing cardiopulmonary bypass through a median sternotomy. The diagnosis and treatment of mediastinitis after cardiac surgical procedures, as well as methods of prevention, are also reviewed.
The bowshock and magnetopause

Results achieved in magnetopause and the bow-shock research during the years 1983-1986 are discussed. The review on bow-shock phenomenona includes work done on the terrestrial bow shock, interplanetary shocks, and bow shocks of other planets, describing research on macroscopic aspects of shocks as well as on the microphysics of quasi-perpendicular and quasi-parallel shocks. In the area of magnetopause research, global aspects of the boundary are first examined. Next, the issues of reconnection and energy transfer through the magnetopause, including viscous and surface-wave phenomena, are considered. Finally, flux-transfer events are discussed in terms of their characteristic magnetic signatures, energetic-particle anisotropies, and distribution with IMF orientations.
Significance of soya trypsin inhibitors in nutrition

Although recent evidence clearly indicates that trypsin inhibitors (TI) and low protein digestibility are the major factors responsible for the pancreatic hypertrophic and growth inhibitory effects of raw soybeans, there was uncertainty regarding the biological threshold level of TI at which these biological effects occur. To obtain such data, dehulled defatted flakes (10% dietary protein) containing graded levels of TI were fed to weanling rats for 4 weeks in two feeding trials. Normal pancreas weights were obtained in rats fed samples in which only 54 to 68% of the original TI of raw soya flour was inactivated. In partially toasted flakes with a nitrogen digestibility value of 77%, the average tolerance level of dietary TI activity that did not cause pancreatic hypertrophy was calculated to be 385 mg TI/100 g diet. TI tolerance level at maximum nitrogen digestibility of 85%, which did not significantly lower weight gain and reduce protein efficiencey ratios, was 260 mg TI/100 g diet. Continuous ingestion of high levels of TI (459 mg TI/100 g diet) in a 20% protein diet for 215 days did not inhibit growth nor cause pancreatic hypertrophy when compared to rats fed toasted soya flour diets. Pancreatic hypertrophy that occurs in rats fed raw soya diets containing up to about 1300 mg TI/100 g diet for 35 days was reversed by switching the rats to control diets or to 30% toasted flour. In long-term feeding studies, no pancreatic hypertrophy occurred in rats fed commercial edible-grade soya flour, concentrate, or isolate from time of weaning to adulthood (ca. 300 to 330 days). TI content of the diets ranged from 178 to 310 mg/100 g diet. Microscopic examination of the pancreas revealed no abnormalities. Gross appearances of heart, kidney, spleen and liver were normal. In long-term feeding, vitamin B-12 supplements were needed to provide optimum growth and to maintain body weight. Results of numerous chemical analyses, relatively short-term human tests and long-term animal feeding studies indicate that with proper control of manufacturing processes, soya protein products can be produced that, in mixed diets, have protein nutritional value approaching that of animal protein.
Ukraine twenty years after independence: Concept models of the society

Abstract This paper attempts to create an overview of the Ukraine twenty years after independence by presenting prevailing conceptual narrative models of Ukraine employed by Ukrainian and foreign experts. Based on the analysis of 58 interviews of Ukrainian political and intellectual elites and foreign experts, the study revealed several categories of conceptual narrative models employed by respondents: (1) a state without a national idea and a common identity; (2) a country in an unfinished transition and degradation; (3) a divided society; and (4) Ukraine as a colony or “wild capitalism”. The analysis of these categories helps to assess conflict potential in Ukraine and discuss some ideas for conflict prevention and resolution.
The Reliability and Concurrent Validity of the GMFCS for Children with Cerebral Palsy

[Purpose] To determine inter-rater and intra-rater reliability using video recordings, and the concurrent validity of the Gross Motor Function Classification System (GMFCS). [Subjects] The subjects who were assessed were 71 children with cerebral palsy (CP; 46 boys, 25 girls) who were divided into three age groups according to the GMFCS guidelines; 0-2 years, 2-4 years, and 4-6 years. [Methods] Eleven pediatric physical therapists rated 71 video recordings of children with CP to test inter-rater reliability. Two of them rescored the same video recordings to test intra-rater reliability at an interval of one month. Concurrent validity was evaluated by comparing GMFCS levels with the subscale of the Pediatric Evaluation of Disability Inventory (PEDI) such as self-care, mobility, and social ability. [Results] By age group, inter-rater reliability was high (ICC = 0.994, 0.993, and 0.996 respectively). Intra-rater reliability was also high (ICC = 0.972-0.996), and correlation was higher between GMFCS level and the mobility domain of PEDI than between GMFCS level and non-motor domains of PEDI. [Conclusion] This study confirmed the reliability and validity of the GMFCS, supporting its use in clinical practice and research.
Effect of current crowding and Joule heating on electromigration-induced failure in flip chip composite solder joints tested at room temperature

The electromigration of flip chip solder joints consisting of 97Pb–3Sn and 37Pb–63Sn composite solders was studied under high current densities at room temperature. The mean time to failure and failure modes were found to be strongly dependent on the change in current density. The composite solder joints did not fail after 1month stressed at 4.07×104A∕cm2, but failed after just 10h of current stressing at 4.58×104A∕cm2. At a slightly higher current stressing of 5.00×104A∕cm2, the composite solder joints failed after only 0.6h due to melting. Precipitation and growth of Cu6Sn5 at the cathode caused the Cu under bump metallurgy to be quickly consumed and resulted in void formation at the contact area. The void reduced the contact area and displaced the electrical path, affecting the current crowding and Joule heating inside the solder bump. Significant Joule heating inside solder bumps can cause melting of the solder and quick failure. The effect of void propagation on current crowding and Joule heating was...
Returns of Small Growth Stocks: An Empirical Analysis

I investigate the mean reversion tendency of small growth stocks. Using a carefully articulated research design employing established and empirically tested principles, my findings should support or refute the anecdotal evidence that small growth stocks make superior investments. The primary motivation for the study springs from the documented differential preference among investors for value and growth stocks. Despite evidence that value stocks tend to outperform growth stocks, investors retain strong interest in growth stocks. Yet in examining the performance of Business Week’s (BW), smaller capitalization companies (called “Hot Growth Companies”) with respect to the overall financial market, Bauman et al. [2002] found positive excess returns in the pre-publication period but negative excess returns in the post-publication period. A limitation of their study is that their analyses relied on only three criteria: sales, BW rank and return on capital, which do not represent completely a firm’s financial health. I replicate Bauman et al.’s study but use a more robust and representative variable set to test the mean reversal hypothesis — Forbes’ financial criteria — and I focus on six variables. In the current study, I look at 4,200 companies listed in Forbes from 1980 to 2000. The results of the expanded study substantiate Bauman et al.’s [2002] study showing that there are positive excess returns in the pre-publication period, but negative excess returns in the post-publication period. An expanded future study will look at five additional variables to see if they make a significant difference on the effects of the returns of small growth stocks.
A study of the chromosomes of Xiphophorus, Platypoecilus and of Xiphophorus-Platypoecilus hybrids during spermatogenesis†

During spermatogonial stages in Xiphophorus and Platypoecilus maculatus and Platypoecilus couchiana and in the hybrid, two distinct types of cells are observed, a large lightly staining primary spermatogonium and a smaller deeply staining secondary spermatogonium. Chromosomes of primary spermatogonia of Platypoecilus maculatus and Platypoecilus couchiana differ somewhat from those of Xiphophorus helleri and Xiphophorus jalapa, but are very similar to those of the hybrid at this stage. Chromosomes of Xiphophorus at this stage are long and thin, while those of Platypoecilus and of the hybrid are somewhat short and thick. Visible chromosome differences appear only during the primary spermatogonial stages. The haploid group of chromosomes, numbering twenty-four in the hybrid, so resembles that of Xiphophorus and of these two species of Platypoecilus in both number and morphological characteristics during the primary spermatocyte division as to be practically indistinguishable from either. Persistent lagging of one large chromosome as it comes upon the equatorial plate during the primary spermatocyte division is very noticeable. Precocious division of this chromosome and the advancing of its two daughter components to the poles of the spindle in advance of other chromosomes indicates that this chromosome may be a sex chromosome. The fact that two daughter components are identical morphologically and that each secondary spermatocyte receives one of them suggests that the male in Xiphophorus and in Platypoecilus is homogametic.
Pentachlorophenol and 3,4-dichloroaniline as models for photochemical reactions in seawater

Abstract Pentachlorophenol (PCP) and 3,4-dichloroaniline (DCA) were used as models to examine photochemical reactions in seawater. The photolysis of PCP in seawater differed in both rate and product distribution from that in distilled water; rates were slower in seawater due to the photonucleophilic interaction of PCP with chloride ions, demonstrated by the formation of 36 Cl-labeled PCP in irradiated PCP solutions containing Na 36 Cl. DCA showed no rate change and gave identical products in both systems. Both PCP and DCA yielded greater amounts of photoreduction products in seawater than in distilled water, and tetrachloromuconic acid was isolated and identified as a new and unstable PCP photoproduct resulting from ringfission. This study demonstrates the operation of photooxidation, photonucleophilic substitution, and photoreduction reactions which differ in detail between seawater and distilled water and suggests that photochemical reactions can be a major factor in the breakdown of organic pollutants and other chemicals in the marine environment.
Effects of Yariv phenylglycoside on cell wall assembly in the lily pollen tube

Arabinogalactan-proteins (AGPs) are proteoglycans with a high level of galactose and arabinose. Their current functions in plant development remain speculative. In this study, (β-D-glucosyl)3 Yariv phenylglycoside [(β-D-Glc)3] was used to perturb AGPs at the plasmalemma-cell wall interface in order to understand their functional significance in cell wall assembly during pollen tube growth. Lily (Lilium longiflorum Thunb.) pollen tubes, in which AGPs are deposited at the tip, were used as a model. Yariv phenylglycoside destabilizes the normal intercalation of new cell wall subunits, while exocytosis of the secretory vesicles still occurs. The accumulated components at the tip are segregated between fibrillar areas of homogalacturonans and translucent domains containing callose and AGPs. We propose that the formation of AGP/(β-D-Glc)3 complexes is responsible for the lack of proper cell wall assembly. Pectin accumulation and callose synthesis at the tip may also change the molecular architecture of the cell wall and explain the lack of proper cell wall assembly. The data confirm the importance of AGPs in pollen tube growth and emphasize their role in the deposition of cell wall subunits within the previously synthesized cell wall.
Rotation invariant texture classification using directional filter bank and support vector machine

This paper presents a rotation invariant texture classification method using a special directional filter bank (DFB) and support vector machine (SVM). This method extracts a set of coefficient vectors from directional subband domain, and models them as multivariate Gaussian densities. Eigen-analysis is then applied to the covariance metrics of these density functions to form rotation invariant feature vectors. Classification is based on SVM, which only takes non-rotated images for training and uses images at various rotation angles for testing. Experimental results have shown that this DKB is very effective in capturing directional information of texture images, and the proposed rotation invariant feature generation and SVM classification method can in fact achieve relatively consistent classification accuracy on both non-rotated and rotated images.
Predictors of necrospermia in men with spinal cord injury

AbstractPurpose: We identify predictors of the lowest yield of dead sperm in ejaculates of men with spinal cord injury.Materials and Methods: The percentages of dead immotile sperm and dead total sperm were compared in 141 spinal cord injured and 52 normal men. Predictors of necrospermia investigated in spinal cord injured men included specimen collection by vibratory stimulation versus electroejaculation, residence of sperm in antegrade versus retrograde specimens and level of injury.Results: Spinal cord injured subjects had a significantly higher percentage of dead sperm in the immotile fraction and total specimen than control subjects. The percentage of dead sperm was lower in antegrade versus retrograde specimens and in specimens produced by vibratory stimulation versus electroejaculation. There was no difference in the percentage of dead sperm by level of injury.Conclusions: Of the parameters evaluated only method and type of specimen collection were predictive of the degree of necrospermia in men wi...
Growth and nutritional responses of bareroot Jeffrey pine on a Sierra Nevada surface mine to minisite applications of fertilizer and lime

The effects of two controlled release fertilizers, Forestcote 22-4-6 + Minors and Dry Site 21-6-2 + Minors, and also dolomitic lime, on growth and nutrition of bareroot Jeffrey pine (Pinus jeffreyi Grev. & Balf.) were investigated. Forestcote, which consists of loose prills, and Dry Site, consisting of prepackaged prills, were administered with two rates, while a single liming rate was used. An acidic Sierra Nevada surface mine provided the study site, and all amendments were applied at outplanting to the backfill of augered planting holes. Without impacting survival, both fertilizer formulations enhanced seedling growth, particularly at a 16 g rather than an 8 g application rate, although Forestcote was marginally more effective in this regard. In contrast, liming at a 27 g rate induced severe mortality and offset much of the growth gains resulting from fertilization. Improvements in N and P nutrition, as revealed by foliar analysis, probably accounted for much of the growth stimulation exhibited by fertilized seedlings, but reductions in the uptake of potentially phytotoxic trace elements such as Mn and Al and increases in base cation/metallic element ratios likely also contributed. The high application rate was generally preeminent in eliciting these nutritional responses. Liming induced little alteration of seedling nutrition. Impaired water relations may have caused the unfavorable responses to this treatment.
Enhancement of four-wave mixing and line narrowing by use of quantum coherence in an optically dense double-? solid.

We have demonstrated enhanced nondegenerate four-wave mixing by use of a resonant probe in a double-? system consisting of an optically dense spectral hole–burning solid. The observed probe diffraction efficiency is ?16% in amplitude at 6??K, which is higher than for an off-resonant probe in a ?-type scheme. We have also observed two-photon coherence line narrowing, which has potential application to high-resolution spectroscopy.
Predicting the Multifractal Geomagnetic Field

The geomagnetic field at the Earth’s surface is determined by a large number of current sources, internal and external, which vary at overlapping time scales. As a result, the time variation of the field, ranging from nHz to tens of Hz, can be modeled as a multifractal whose properties depend on frequency and activity level, with the latter being largely determined by the external driving due to the interplanetary medium. Multifractal properties are apparent in all measures, conventional or modern, of magnetic activity: the magnitude and individual components; regional and global nonlinear averages known as magnetic indices; and nonstationary oscillations due to wave excitation and damping. In recent years, we have developed predictive models of the three types of measures which are representations of the field’s modes of response to interplanetary magnetic and plasma variables. Thus, although the field’s time variation appears multifractal, many of its features are predictable since they are related to nonlinear modes in response to the turbulent interplanetary medium. We present two examples: the predictive modeling of the high-latitude field disturbances as a response to the interplanetary electric field, and that of its derivative, / t ∂ ∂ B , at midand high latitudes as a response to the solar wind plasma moments. We discuss the merits and disadvantages of the “modal” versus the “multifractal” approach.
Determination of efficacy of acute normovolemic hemodilution through mathematical modeling

Acute normovolemic hemodilution (ANH) has been proposed as a safe and cost-effective replacement for traditional blood transfusion techniques in hemorrhaging during surgery. Its practice is underutilized because its efficiency is unknown. Here, we present a mathematical modeling approach to determine the efficacy of ANH.
Transition metal cation separations with a resorcinarene-based amino acid stationary phase

A resorcinarene-based macrocyclic ligand functionalized with alanine and undecyl groups (AUA) was synthesized and applied to ion chromatographic separations. The selectivity and separation of transition metal ions on a column packed with AUA adsorbed onto 55% cross-linked styrene–divinylbenzene resin are presented. The upper and lower rims of the resorcinarene were modified with amino acids and –C11H23 alkyl chains, respectively. The four carboxylic acid groups on the upper rim act as cation-exchangers while the four –C11H23 alkyl chains serve to anchor the ligand to the resin surface by the hydrophobic effect. A systematic study of the effect of different eluent components including non-metal-chelating (HNO3) and chelating acids (oxalic acid, succinic acid, dipicolinic acid, and citric acid) on the retention of transition metal ions was investigated. Six metal ions (Mn2+, Co2+, Ni2+, Cd2+, Cu2+, and Zn2+) were separated on the AUA column within a reasonable time with a single eluent gradient using oxalic acid. The separation is compared to that obtained using a commercial column containing carboxylic acid functional groups. The AUA column containing four preorganized carboxylic acid groups showed selectivity for Cu2+ when no chelating eluent was present, a selectivity which was not observed with the comparison column.
Hepatic MR Imaging Techniques, Optimization, and Artifacts

This article describes a basic 1.5-T hepatic magnetic resonance (MR) imaging protocol, strategies for optimizing pulse sequences while managing artifacts, the proper timing of postgadolinium 3-dimensional gradient echo sequences, and an effective order of performing pulse sequences with the goal of creating an efficient and high-quality hepatic MR imaging examination. The authors have implemented this general approach on General Electric, Philips, and Siemens clinical scanners.
Articulation of computer science curricula at the community colleges and the universities

An example of a solution to the problem of a student majoring in Computer Science/Data Processing at a Community College transferring to a university and continuing his degree program will be presented. Audience participation will be encouraged.
Nature of the Binding Interaction for 50 Structurally Diverse Chemicals with Rat Estrogen Receptors

This study was conducted to characterize the estrogen receptor (ER)–binding affinities of 50 chemicals selected from among the high production volume chemicals under the U.S. EPA’s (U.S. Environmental Protection Agency’s) Toxic Substances Control Act inventory. The chemicals were evaluated using the rat uterine cytosolic (RUC) ER-competitive binding assay, with secondary analysis using Lineweaver-Burk plots and slope replots to confirm true competitive inhibition and to determine an experimental Ki. Data from these ER-competitive binding assays represent the types of competitive binding curves that can be obtained when screening chemicals with broad structural diversity. True competitive inhibition was observed in 17 of 50 chemicals. Binding affinities were much lower than that of estradiol (E2) with Ki concentrations ranging from 0.6 to 373mM as compared with that of E2 (0.77nM). Other chemicals that appeared to displace radiolabeled E2 binding to ER were, in fact, found not to be competitive inhibitors in the secondary Ki experiments. These seven chemicals likely altered the stability of the assay by changing the buffer pH, denaturing ER, or disrupting the ERbinding kinetics. Thus, several conditions that may confound interpretation of RUC ER-binding assay data are illustrated. For another group of eight chemicals, neither an IC50 nor Ki could be determined due to solubility constraints. These chemicals exhibited slight (20–40%) inhibition at concentrations of 10–100mM, suggesting that they could be competitors at very high concentrations, yet Ki experiments were not possible as the limit of chemical solubility in the aqueous assay buffer was well above the IC50. An additional 18 of the 50 chemicals were classified as nonbinders because in concentrations up to 100mM they produced essentially no displacement of radiolabeled E2. These results show that although the ER-competitive binding assay is a valuable tool for screening chemicals, secondary tests such as a double reciprocal Lineweaver-Burk experiment with slope replot should be used to confirm true competitive inhibition. This information will be useful for the ongoing validation of the RUC ER-competitive binding assay under the U.S. EPA’s Endocrine Disruptor Screening Program, as well as to support research efforts to develop computational models designed to identify chemicals with the ability to bind to ER.
Real-time photorefractive recording and optical processing for speckle velocimetry.

A photorefractive crystal (Bi12GeO20) is used to record double-exposure speckle patterns produced by Q-switched laser pulses in real-time speckle metrology and velocimetry applications. The speckle pattern displacements are immediately measured with an optical processor of the type used for measuring speckle displacements recorded on photographic film. Operation of the optical processor is described and compared with the case of film recording. Observed spatial and temporal recording properties of the crystal in this imaging configuration are discussed and compared with published results for single-frequency grating recording in photorefractives. The system is applied to measuring velocities of a moving solid object.
Attachment theory and its vicissitudes: Toward an updated theory:

This paper attempts first steps toward reworking Bowlby’s attachment theory and formulating an updated version. The paper examines 11 tenets of attachment theory as it was originally proposed by Bowlby and colleagues. These tenets are discussed in terms both of historical and recent criticisms, and of relevant research. Reasons are given for why the discussion omits work involving animal models or focused on measurement issues. In conclusion, the tenets are assigned to four categories: ideas that have received little criticism; ideas that have been criticized but are generally accepted, although they need to take new research evidence into account; ideas that have been rejected or questioned more than they have been accepted; and ideas that have been rejected or extensively reinterpreted.
Mechanism of dynamic nuclear polarization in high magnetic fields

Solid-state NMR signal enhancements of about two orders of magnitude (100–400) have been observed in dynamic nuclear polarization (DNP) experiments performed at high magnetic field (5 T) and low temperature (10 K) using the nitroxide radical 4-amino TEMPO as the source of electron polarization. Since the breadth of the 4-amino TEMPO EPR spectrum is large compared to the nuclear Larmor frequency, it has been assumed that thermal mixing (TM) is the dominate mechanism by which polarization is transferred from electron to nuclear spins. However, theoretical explanations of TM generally assume a homogeneously broadened EPR line and, since the 4-amino TEMPO line at 5 T is inhomogeneously broadened, they do not explain the observed DNP enhancements. Accordingly, we have developed a treatment of DNP that explicitly uses electron–electron cross-relaxation to mediate electron–nuclear polarization transfer. The process proceeds via spin flip–flops between pairs of electronic spin packets whose Zeeman temperatures di...
Slow slip predictions based on granite and gabbro friction data compared to GPS measurements in northern Cascadia

Received 7 October 2008; revised 17 April 2009; accepted 12 June 2009; published 29 September 2009. [1] For episodic slow slip transients in subduction zones, a large uncertainty in comparing surface deformations predicted by forward modeling based on rate and state friction to GPS measurements lies in our limited knowledge of the frictional properties and fluid pore pressure along shallow subduction faults. In this study, we apply the laboratory rate and state friction data of granite and gabbro gouges under hydrothermal conditions to a Cascadia-like 2-D model to produce spontaneous aseismic transients, and we compare the resulting intertransient and transient surface deformations to GPS observations along the northern Cascadia margin. An inferred region along dip of elevated fluid pressure is constrained by seismological observations where available and by thermal and petrological models for the Cascadia and SW Japan subduction zones. For the assumed
Emergence phenology of Osmia lignaria subsp. lignaria (Hymenoptera: Megachilidae), its parasitoid Chrysura kyrae (Hymenoptera: Chrysididae), and bloom of Cercis canadensis.

ABSTRACT Emergence patterns of a natural population of Osmia lignaria subsp. lignaria Say were monitored during a 5-yr period (2003–2007) in relation to air temperature, bloom of eastern redbud (Cercis canadensis L.), and emergence of the parasitoid Chysura kyrae Krombein. Bee cocoons were placed in gelatin capsules and overwintered within shelters in their natural habitat. Mean emergence of female O. l. lignaria was observed at ≈2 d after redbud bloom began; mean male emergence was ≈ 1 wk earlier than for females and was nearly identical to that of C. kyrae. Horticultural models used to predict budburst for several tree species were evaluated with respect to redbud bloom and O. l. lignaria emergence. Each model indicated that both sexes of the bee and redbud had similar chill unit requirements. Differences in emergence and bloom dates were attributed to the different requirements for growing degree hours (GDHs) after chilling requirements were met. The close phenological relationship observed between eas...
The ponzo illusion: inadequacy of apparent depth explanations.

Os viewing the Ponzo figure reported a series of sudden changes in its phenomenal organization and orientation. In none of these was the vertical line nearer the vertex of the figure reported to be smaller than the vertical line nearer the open end, i.e., the illusion occurred with all percepts except a rare one of a flat stimulus. In two of the most frequent and persistent percepts, the illusion could be explained on the basis of apparent size-apparent distance relationship among the elements. This was also the case with Gregory's theory of misapplied size-constancy scaling. However, with other percepts neither of these explanations was tenable.