cssi/SciSciGPT-SciSciNet huggingface dataset:
Preschool Denver Developmental Screening Testas a predictor of later school problems

We compared three preschool tests as predictors of school problems at the end of first grade. A stratified sample of 113 4 1/2- to 5 1/2-year-old children, oversampling those at risk for developmental difficulties, was administered the Denver Developmental Screening Test (DDST), the Stanford-Binet IQ test (SB), and a two-stage shortened form of the DDST in the spring before school entry. Data from achievement tests, special class placement, and grade retention were obtained for 106 of the children at the end of first grade. Eighty-four percent of children with abnormal DDST scores had school difficulties by the end of first grade, compared with 47% of children with scores in the questionable range and only 15% of children in the normal range. Prediction from the SB was not as accurate; 72% of the children who scored less than 68 and 42% of those who scored between 68 and 84 on the preschool SB had school problems. Prediction for those children who had abnormal or questionable scores on the two-stage DDST was as good as prediction from the full DDST. However, far fewer of the total number of school problems were identified by the two-stage DDST. It appears that the DDST can be used on an individual basis for prediction of school problems.
The Meaning Makes It Fun

AbstractMuseum games can be a powerful meaning-making experience for players, but only if we understand that what makes games fun is also what makes them meaningful. Renowned game designer Sid Meier (Civilization, Railroad Tycoon, Pirates) famously defined a good game as “a series of interesting choices.” What makes choices interesting? The same things that make them meaningful: consequences, context, and a sawy appeal to human psychology. When designed well, these choices can make even mundane content meaningful. So imagine the possibilities when we use the stuff of museums—art, science, history, and technology—as our content and context. Whether creating a game or a simpler activity, we can draw on principles of game design to weave a series of interesting choices that honors our real-world content while engaging visitors in thoughtful ways. This article considers that most common type of “game”—the quiz—before analyzing the board game Monopoly for attributes of interesting choices, and finally discusse...
Gender differences in perceived intimacy with different members of adolescents' social networks

Previous research has clearly established important gender differences in how intimacy is viewed within a narrow set of relationships, primarily those with same-sex peers. This article presents a new social pressures model that delineates a set of diverse forces believed to influence gender differences in intimacy across a much wider set of social relationships during early adolescence. Although it was impossible to examine the actual operation of the postulated pressures, an extensive data set on all the important people in the lives of over 2000 seventh- through tenth-grade white suburban adolescents made it possible to test a set of 22 hypotheses derived from the model. These hypotheses covered relationships with nuclear, extended family, and nonkin members of the social network who were of different ages and genders. Results indicated that, while gender differences in the perceived intimacy of relationships were widespread, they were neither present in all types of relationships nor were those found always in the same direction. Furthermore, the social pressures model developed accurately predicted both the location and direction of the gender differences across most of the 22 different types of relationships. Suggestions for an elaboration of the model are noted, along with additional research issues that need to be addressed.
Severe sepsis: international and specialty variations in initial management

Four years after release of the Surviving Sepsis Campaign (SSC) guidelines, doctors' approaches to early sepsis resuscitation are unknown. We sought to understand the strategies used in Australasia (ANZ), the United Kingdom and the USA.
Radar Precipitation Echoes Experiments on Temporal, Spatial, and Frequency Correlation

This paper summarizes measurements of the characteristics of precipitation clutter. The goal was to provide for the radar engineer a description of the spectrum, the spatial uniformity, and the frequency correlation properties of precipitation echoes. These experiments resulted in a more complete description of the clutter characteristics than has heretofore been available. The wind shear phenomenon was found to have a dominant effect on the spectra at distant ranges. An analytical model for the spectral width is suggested. Other results show that the mean backscatter cross section is rarely uniform in space and that the frequency correlation characteristics confirm the theory predicting that echoes from pulses separated in frequency by at least the reciprocal of the pulse width are uncorrelated.
OCCUPATIONAL AND ENVIRONMENTAL MEDICINE AND PRIMARY CARE

This article introduces occupational and environmental medicine (OEM) to physicians in other specialties, and especially to primary care physicians, by highlighting the common foundations of OEM practice and primary care practice. These common foundations include careful diagnosis and treatment, appropriate use of consultants, collaboration with non-medical professionals, attention to psychosocial issues, care of the entire family, respect for confidentiality, patient education, preventing disability and maximizing function, diligent patient follow-up, epidemiological thinking, and continuing medical education.
Volatile trace elements in Antarctic ureilites

— We report data for Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U and Zn in 15 different Antarctic ureilites. Contents of these mainly volatile trace elements in Antarctic ureilites are roughly comparable to those in the four known falls. Trends exhibited by these data apparently reflect geochemical fractionations in parental magma(s), which were closed to loss of vapor. Subsequent events (e.g., shock and crystallization) do not seem to have affected contents of these elements.
Immunologic assay of alpha-1-antitrypsin in deficient subjects and their families.

Alpha1-antitrypsin (alpha1-at) concentration in serum was measured by a method of single radial diffusion. The normal concentration was 212±32 mg/100 ml. Values for members of the families in which the alpha1-at deficiency occurred were trimodally distributed with values of 25±6, 120±46, and 227±56 mg/100 ml. Subjects with low values were homozygous for the deficiency gene, those with intermediate values were heterozygous, and those with normal values were homozygous for the normal gene.
The role of sensory structures and preoviposition behavior in oviposition by the patch butterfly, Chlosyne lacinia.

The role of antennae and foretarsi in oviposition and host discrimination was investigated in Chlosyne lacinia Geyer (Nymphalidae, Lepidoptera) a cluster laying nymphalid butterfly which exhibits drumming and antennal dipping behavior prior to oviposition. Ablation of the entire antennae drastically reduced oviposition, while fractional antennectomy reduced it in proportion to the number of antennal receptors removed. Host/non-host ovipositional discrimination was not significantly affected by antennal ablations. Ablation of the foretarsi abolished discrimination in a controlled environment chamber, but did not affect it in outdoor cages or in a greenhouse. This difference was retrospectively associated with a diminished release of host volatiles due to cooler leaf surface temperatures in the environmental chamber or with continuous air turbulance caused by humidifier fans in the environmental chamber. Electrophysiological techniques were used to demonstrate chemosensory activity in setae located on the foretarsi. We conclude that foretarsal contact chemoreceptors employed during drumming are used for host verification in environmental conditions where olfaction is unreliable. RESUME Influence sur la ponte de Chlosyne lacinia Geyer (Lep. Nymphalidae) des structures sensorielles et du comportement precedant la ponte Le role des antennes et des tarses anterieurs sur la ponte et la selection des hotes a ete etudie chez Chlosyne lacinia, papillon nymphalide aux pontes groupees, dont le comportement avant la ponte comporte un tambourinage et un picotage antennaire. L'ablation integrate des antennes reduit brutalement la ponte, une antennotectomie partielle la reduit proportionnellement au nombre de recepteurs antennaires elimines. Les ablations antennaires n'affectent pas significativement la discrimination entre plantes — hotes ou non. L'ablation des tarses anterieurs supprime la discrimination en piece climatisee, mais non en serre ou en cages a l'exterieur. Cette difference peut etre expliquee par une liberation reduite de substances volatiles dans les chambres climatisees avec des surfaces foliaires plus froides ou par la turbulence permanente de l'air qui y etait provoquee par les ventilateurs des humidificateurs. Des techniques electrophysiologiques ont ete utilisees pour deceler l'activite chimiosensorielle des setae des tarses anterieurs. Nous concluons que des recepteurs chimiques de contact des tarses anterieurs sont utilises pendant le tambourinage pour controler l'hote dans des conditions ecologiques ou l'olfaction est inutilisable.
BIOLOGICAL DISTANCES ON DNA KNOTS AND LINKS: Applications to XER recombination

The mathematics of tangles has been very useful in studying recombinases which act processively and which require DNA to be in a certain configuration in order for the enzyme to act. Electron micrographs of the enzyme-DNA complex show the enzyme as a blob with DNA looping out of it. The configuration of the DNA within the blob cannot be determined form the electron micrographs. However, mathematics can in some cases determine the configuration of the DNA within the enzyme blob as well as the enzyme action. In this paper, several theorems used to analyze recombinase experiments are summarized. In particular Xer recombinase, an enzyme which does not act processively is analyzed. Unfortunately, for enzymes which do not act processively, infinitely many possibilities exist. Several experiments are proposed to reduce this number and to emphasize both the usefulness and limitations of tangle analysis. Although the local action cannot be mathematically determined without more biological assumptions, it is possible to determine the topology of the synaptic complex through additional biolgical experiments.
Allometry and ecology of feeding behavior and digestive capacity in herbivores: a review

The purpose of this review is to give some perspective of the factors that influence feeding behaviors and the ability of herbivores to adapt to diets. The most important of these are digestibility, ability to select feed, and achievement of a nutritionally adequate intake. Plant morphology, observed feeding behavior, body size, and gut architecture and size impinge upon these factors. Feeding behavior and dietary specializations are associated with adaptations of gut and mouth parts as well as body size. Parallel and overlapping behaviors occur among herbivores and particularly between ruminants and nonruminants. The conventional classifications of grazers, browsers, and selective feeders are blurred by these evolutionary developments. © 1996 Wiley-Liss, Inc.
Survey Data on Precollege Scope-and-Sequence Issues in Economics

The author reports on an extensive survey of economic educators on the topic of the scope and sequence of economics instruction at the elementary and secondary levels.
Study of the 1s orthoexciton luminescence in Cu2O under two-photon excitation

Abstract We have studied the luminescence of 1s orthoexcitons in Cu 2 O under both resonant and non-resonant two-photon excitation. The intensity of the luminescence was enhanced while resonantly exciting at the 1s or 2s orthoexciton levels. The direct and phonon-assisted emissions were observed over a wide range of temperatures (1.8–294 K) under two-photon resonant excitation. The phonon-assisted spectra can be well fit with a Maxwellian distribution with a fitting temperature close to the lattice temperature. The integrated intensity shows a minimum at 20 K and a maximum around 180 K. The existence of the direct emission feature enables us to deduce the temperature dependent bandgap and the orthoexciton line width directly up to relatively high temperatures. The red-shift of the orthoexciton energy and the increase of its line width as the temperature increases are interpreted as a temperature dependence of the real and imaginary parts of the exciton self energy.
Antitumor actions of interferon-gamma and interleukin-1 beta on human papillary thyroid carcinoma cell lines.

To test the hypothesis that interferon-gamma (IFN gamma) and interleukin-1 beta (IL-1 beta) possess antitumor activity on human papillary thyroid carcinoma cells, we studied the in vitro effects of IFN gamma and IL-1 beta on the proliferation and invasiveness of two human PTC cell lines, TPC-1 (TP) and NPA (NP) cells. TP and NP cells were treated with various concentrations of IFN gamma and IL-1 beta alone and in combination. Cell proliferation was assessed by [3H]thymidine incorporation and cell number measurement. Tumor cell invasion was assessed by the ability of cells to penetrate through a Matrigel membrane. Both IFN gamma and IL-1 beta inhibited [3H]thymidine incorporation into TP cells in a dose-dependent manner and decreased TP cell number. In NP cells, treatment with IFN gamma and IL-1 beta also decreased [3H]thymidine incorporation and cell number. The inhibitory effects of IFN gamma and IL-1 beta on tumor cell proliferation were additive in both cell lines. In the invasion experiments, IFN gamm...
International debt renegotiation: Lessons from the past

Debt treatment by creditors when relief of contractual obligations was required are considered from World War I to the present. Prior to World War I, debt relief arrangements had little regard for the underlying economic position of the debtor country, and thus had to be repeatedly renegotiated, usually on terms less favorable to the creditors. After World War I, the international credit extended to Germany in association with its war reparations was based on considerations of what Germany could pay rather than should pay. After World War II, the multilateral London Conference in German External Debt of 1953, a milestone in the history of the treatment of international debt, agreed to settle all of Germany's pre-war external debts on generous terms, contributing to Germany's rapid recovery. In the post-war period international debt became associated primarily with private lending, and institutions arose for the purpose of short-term relief for commercial debts. The Paris Club was a creditors' consortium that provided minimum relief required in order to prevent default. The OECD aimed for economic rehabilitation of LDCs through official lending.
Regularized logistic regression based classification for infrared images

There is an increase in the bird and bat mortality near wind farms. It is desirable to document and quantify behavior and activity of birds/bats near wind farms. Infrared Imaging is a useful monitoring method for this purpose. However, IR images do not provide information as whether the target is a bird, bat or insect. A logistic regression classifier is used to provide category information of the targets. There are no priori known database of images available for birds, and bats. Features of targets are extracted and used for classification purpose. A database of labeled category based on the features has been created.
Impact of Urethral Stump Length on Continence and Positive Surgical Margins in Robot-Assisted Laparoscopic Prostatectomy

Introduction We previously reported the benefit of meticulous apical dissection in reducing positive surgical margins (SM+) at the apex. Herein we assess whether a more aggressive urethral transection will reduce positive margins and whether reduced urethral length affects return to continence. Technical Considerations All data were collected prospectively. A positive surgical margin was defined by the presence of cancer cells with ink on them. Continence, defined as no pads, was assessed with validated Expanded Prostate Cancer Instrument Composite questionnaires. Evaluation of 200 consecutive cases (group 1) revealed that 75% of surgical margins occurred at the apex. Concomitantly we assessed visual cues for urethral length, which demonstrated that even patients with very short urethral stumps requiring perineal pressure during anastomosis had equivalent times to continence as those with long, accessible stumps. We altered the point of transection, distally, to include 3 to 6 mm more of striated external urethral sphincter. The SM+ rate and time to continence for the ensuing 200 cases (group 2) were tracked. The overall SM+ and apical SM+ rates were significantly reduced (SM+ 17.6% versus 7.5%, P = 0.003; and apical SM+ 13% versus 5.5%, P = 0.01). Kaplan-Meier times to continence curves were not significantly different. Conclusions A more aggressive apical resection resulted in marked reduction in overall SM+ rates without measurable change in time to continence or overall continence.
Effect of dietary fructose on in vitro and in vivo fatty acid synthesis in the rat

Abstract Diets containing either glucose or fructose as the only source of carbohydrate were fed to rats. [U- 14 C] Glucose and [U- 14 C] fructose incorporation into fatty acids by liver slices from these animals indicated that the results obtained were markedly affected by substrate concentration. At a level of 10 mM fructose incorporation into hepatic fatty acids was greater than that observed with glucose; however, the reverse was true when the substrate concentration was increased to 100 mM. High levels of fructose in the incubation medium markedly depressed ATP levels in liver slices and also inhibited [ 14 C]-acetate incorporation into fatty acids. Rats fed fructose had higher hepatic ATP levels than did rats fed glucose. In vivo estimates of fatty acid synthesis were obtained using [ 14 C] acetate as well as 3 H 2 . These determinations indicated that while the total capacity of the animal to synthesize fatty acids was unchanged, the relative importance of the liver was increased and that of the extra-hepatic tissues decreased when fructose, rather than glucose, was fed to rats.
Is Geography (Still) a Science

Geographic science remains contested. The practice of geographic science has long been criticized on both methodological and institutional grounds, often justifiably. Even more serious is the continuing assault on the very idea of science as the objective discovery of and search for explanation in the university, including human behaviour in space and place. This essay argues that a scientific epistemology is incompatible with a relativistic one.
Acid denaturation of DNA in the presence of a polyanion.

Abstract 1. 1. Acid denaturation and renaturation of T1 bacteriophage DNA were studied with a view to determine whether the presence of additional polyanions would influence the helix-coil transition under conditions when such influence would be most likely to manifest itself. Polyglucose sulfate, a strong polyanion with high charge density, did not alter the temperature transition even at pH values close to the denaturation pH. Renaturation rates upon cooling were similarly unaffected by the presence of the strong polyanion. Also unaffected were the acid-induced transitions: pH m values and the shape of the transition curves. Similar data were obtained for T2 DNA, as well as for DNA prepared from polyglucose sulfate-inactivated phage. Thus, the generallu accepted practice of disregarding mutual electrostatic effects of various polynucleotide molecules when present in mixture and in high concentration near physiological salt concentration, appears to be justified. 2. 2. In experiments with DNA alone, when the decreasing thermal stability of the helix at decreasing pH values was studied, a close parallel was observed between the lowering of the transition midpoint and the take-up of protons by the bases.
Understanding the success of nonrelativistic potential models for relativistic quark-antiquark bound states

We investigate the connection between relativistic potential models for quark-antiquark bound states and the nonrelativistic models that have been used successfully to fit and predict the spectra of relativistic systems, as in the work of Martin. We use Martin's operator inequality $\sqrt{{p}^{2}{+m}^{2}}l~{(p}^{2}{+M}^{2}{+m}^{2})/2M$ to motivate the approximation of the relativistic kinetic energy terms in the spinless Salpeter equation by expressions of the nonrelativistic form $M+\ensuremath{\epsilon}{+p}^{2}/2M$ for each quark. To investigate the validity of the resulting approximation numerically, we generate energy spectra for $q\overline{q}$ mesons composed of two light or two heavy quarks using the spinless Salpeter equation with the linear-plus-Coulomb potential typical of phenomenological fits to $q\overline{q}$ data, and then fit the lowest few states of each type using the effective Schr\"odinger description with the same potential. We find good fits to the lowest four calculated $c\overline{c}$ and the lowest three $s\overline{s}$ states either taking M fixed at the value ${M}_{q}=\sqrt{〈{p}^{2}〉{+m}_{q}^{2}}$ that minimizes the Martin bound, or allowing ${M}_{q}$ to vary in the fit. The energies of the lowest few $c\overline{s}$ states are then predicted with similar accuracy. The reasons for the success of the nonrelativistic approximation are identified, and explain the success of Martin's nonrelativistic predictions for the spectra of relativistic light-heavy mesons. However, we note that the agreement between the nonrelativistic and relativistic wave functions is not good, a point of potential concern for the calculation of transition matrix elements.
Physiologic, Biochemical, and Histologic Correlates Associated with Tidal Liquid Ventilation

Tidal liquid ventilation (TLV) with perfluorochemical fluid (PFC) has been successfully used experimentally for up to 4 h. However, no studies of prolonged TLV have been reported. We hypothesized that full-term newborn lambs can safely and effectively be liquid-ventilated for up to 24 h. To test this hypothesis, 17 lambs were liquid-ventilated; 7 for 4 h, 5 for 12 h, and 5 for 24 h. Arterial blood samples were obtained for PFC uptake, lipid analysis, and blood gas measurements. Tissues were obtained for histologic and biochemical analysis. Arterial blood gas and mean arterial blood pressure were as follows (mean +/- SEM): pH 7.48 +/- 0.04; PaCO2 30.6 +/- 2.8; PaO2 424 +/- 17; mean arterial pressure 76 +/- 16 mm Hg. PFC blood levels increased rapidly to a mean of 5.2 +/- 3.9 microg/mL. PFC tissue levels increased significantly (p < 0.01) from 260 +/- 45 microg/g at 4 h to 400 +/- 140 microg/g at 12 h. There was no further increase in PFC tissue levels by 24 h (456 +/- 181 microg/g). There was a significant difference in PFC concentration as a function of tissue (p < 0.01). Furthermore, there was a significant correlation (r = 0.88; p < 0.01) between the amount of PFC and lipid in blood and tissue. Microscopic examination of the lungs demonstrated no evidence of barotrauma. These data demonstrate that prolonged TLV can be safe and efficacious for up to 24 h in full-term newborn lambs.
Online detector response calculations for high-resolution PET image reconstruction

Positron emission tomography systems are best described by a linear shift-varying model. However, image reconstruction often assumes simplified shift-invariant models to the detriment of image quality and quantitative accuracy. We investigated a shift-varying model of the geometrical system response based on an analytical formulation. The model was incorporated within a list-mode, fully 3D iterative reconstruction process in which the system response coefficients are calculated online on a graphics processing unit (GPU). The implementation requires less than 512 Mb of GPU memory and can process two million events per minute (forward and backprojection). For small detector volume elements, the analytical model compared well to reference calculations. Images reconstructed with the shift-varying model achieved higher quality and quantitative accuracy than those that used a simpler shift-invariant model. For an 8 mm sphere in a warm background, the contrast recovery was 95.8% for the shift-varying model versus 85.9% for the shift-invariant model. In addition, the spatial resolution was more uniform across the field-of-view: for an array of 1.75 mm hot spheres in air, the variation in reconstructed sphere size was 0.5 mm RMS for the shift-invariant model, compared to 0.07 mm RMS for the shift-varying model.
Tuning Pharmacokinetics and Biodistribution of a Targeted Drug Delivery System Through Incorporation of a Passive Targeting Component

Major challenges in the development of drug delivery systems (DDSs) have been the short half-life, poor bioavailability, insufficient accumulation and penetration of the DDSs into the tumor tissue. Understanding the pharmacokinetic (PK) parameters of the DDS is essential to overcome these challenges. Herein we investigate how surface chemistry affects the PK profile and organ distribution of a gold nanoparticle-based DDS containing both a passive and active targeting moiety via two common routes of administration: intravenous and intraperitoneal injections. Using LC/MS/MS, ELISA and INAA we report the half-life, peak plasma concentrations, area under the curve, ability to cross the peritoneal barrier and biodistribution of the nanoconjugates. The results highlight the design criteria for fine-tuning the PK parameters of a targeted drug delivery system that exploits the benefits of both active and passive targeting.
Short-term retention of superimposed and of spatially distinct multiletter visual arrays.

On each trial, Ss attempted to retain a series of five visually presented letters while concurrently “shadowing” (repeating aloud) a rapid series of aurally presented letters. If serial-position accuracy is ignored, they were able to store more than only the last letter of a typical series, even though all five letters appeared on the same screen, and that performance was superior to the retention of five auditorily presented letters. Together, these findings suggest that a form of visual storage might have been employed for the retention of visual stimuli and, specifically, one that was relatively immune to erasure as compared to “iconic” storage. In further support of that hypothesis, retention of such visual series as measured by free-recall accuracy was not inferior to that of five letters, each of which was presented on a separate screen.
A Global Climatology of Surface Wind and Wind Stress Fields from Eight Years of QuikSCAT Scatterometer Data

Abstract Global seasonal cycles of the wind and wind stress fields estimated from the 8-yr record (September 1999–August 2007) of wind measurements by the NASA Quick Scatterometer (QuikSCAT) are presented. While this atlas, referred to here as the Scatterometer Climatology of Ocean Winds (SCOW), consists of 12 variables, the focus here is on the wind stress and wind stress derivative (curl and divergence) fields. SCOW seasonal cycles are compared with seasonal cycles estimated from NCEP–NCAR reanalysis wind fields. These comparisons show that the SCOW atlas is able to capture small-scale features that are dynamically important to both the ocean and the atmosphere but are not resolved in other observationally based wind atlases or in NCEP–NCAR reanalysis fields. This is particularly true of the wind stress derivative fields in which topographic, SST gradient, and ocean current influences on surface winds are plainly visible. Discussions of five example regions are presented to highlight these seasonally re...
Synthesis of Hydrophenanthrene Natural Products. An Improved Synthesis of 13-Substituted Dehydroabietane Derivatives from Dehydroabietic Acid

Abstract An improved overall synthesis of 13-carboxydeisopropyldehydro-abietanes from dehydroabietic acid is reported. This important synthetic intermediate is obtained in greater than 20% overall yield, an almost tenfold increase in the yield obtained using previously published procedures. The first synthesis of 15-hydroxydehydroabietanol, a natural product isolated from pine tar oil and an intermediate in the preparation of the title compound, has been accomplished.
The effect of quantum flux density and net photosynthetic rate on morphology and time to flower of hybrid geraniums

Abstract Three cultivars of 63-day-old hybrid geraniums (Pelargonium × hortorum Bailey) were grown under high (800–1200 mE m−2 s−1), medium (300–600 mE m−2 s−1) or low (100–160 mE m−2 s−1) quantum flux densities. Plants grown under low light and 25% greater total leaf area but 25% lower dry weight than plants grown under medium or high levels, regardless of cultivar. Time to flower in all cultivars was negatively correlated with quantum flux density, and specific leaf weight and leaf thickness were positively correlated to net photosynthetic rate. ‘Sprinter Scarlet’ and ‘Sooner Red’ had similar correlation coefficients (r) for most relationships, but r values for ‘Ringo’ were generally not as strong. Quantum flux density appears to affect both organogenesis and maturation of the flower.
The dynamic structure of the pericellular matrix on living cells

Although up to several microns thick, the pericellular matrix is an elusive structure due to its invisibility with phase contrast or DIC microscopy. This matrix, which is readily visualized by the exclusion of large particles such as fixed red blood cells is important in embryonic development and in maintenance of cartilage. While it is known that the pericellular matrix which surrounds chondrocytes and a variety of other cells consists primarily of proteoglycans and hyaluronan with the latter binding to cell surface receptors, the macromolecular organization is still speculative. The macromolecular organization previously could not be determined because of the collapse of the cell coat with conventional fixation and dehydration techniques. Until now, there has been no way to study the dynamic arrangement of hyaluronan with its aggregated proteoglycans on living cells. In this study, the arrangement and mobility of hyaluronan-aggrecan complexes were directly observed in the pericellular matrix of living cells isolated from bovine articular cartilage. The complexes were labeled with 30- to 40-nm colloidal gold conjugated to 5-D-4, an antibody to keratan sulfate, and visualized with video-enhanced light microscopy. From our observations of the motion of pericellular matrix macromolecules, we report that the chondrocyte pericellular matrix is a dynamic structure consisting of individual tethered molecular complexes which project outward from the cell surface. These complexes undergo restricted rotation or wobbling. When the cells were cultured with ascorbic acid, which promotes production of matrix components, the size of the cell coat and the position of the gold probes relative to the plasma membrane were not changed. However, the rapidity and extent of the tethered motion were reduced. Treatment with Streptomyces hyaluronidase removed the molecules that displayed the tethered motion. Addition of hyaluronan and aggrecan to hyaluronidase-treated cells yielded the same labeling pattern and tethered motion observed with native cell coats. To determine if aggrecan was responsible for the extended configuration of the complexes, only hyaluronan was added to the hyaluronidase-treated cells. The position and mobility of the hyaluronan was detected using biotinylated hyaluronan binding region (b-HABR) and gold streptavidin. The gold-labeled b-HABR was found only near the cell surface. Based on these observations, the hyaluronan-aggrecan complexes composing the cell coat are proposed to be extended in a brush-like configuration in an analogous manner to that previously described for high density, grafted polymers in good solvents.
Breast cancer screening and ethnicity in the United States: implications for health disparities research

Ethnic and racial minority women within the U.S. are less likely to use breast cancer screening (BCS) procedures than non-Latina White women, and are more likely to be diagnosed with cancer at later stages of disease. Previous studies examining Latina rates of screening and disease have used aggregated populations for comparison, possibly attenuating important ethnic healthcare disparities and yielding misleading findings. The purpose of this study was to examine if ethnicity matters in understanding current estimates of BCS patterns among U.S. women; to test if healthcare disparities in BCS are present, and if any ethnic/racial groups are primarily affected. The authors used multivariate multinomial regression to examine self-reported mammogram and clinical breast exam in the 2007 full-year U.S. Medical Expenditure Panel Survey. Mexican origin women reported the lowest rates of past-year mammograms and clinical breast examination. Factors enabling healthcare moderated the group’s lower likelihood of mammograms and clinical breast examination. Some breast cancer screening parity appears to have been achieved in 2007 for Black and some Latina groups; however, those rates lag behind for the largest Latino ethnic group, Mexican. Factors enabling healthcare access, such as education, income and insurance, attenuated the BCS inequalities found for Mexican origin women. Findings suggest that successful efforts to reduce BCS disparities be strategically redirected to include women of Mexican origin in addition to other underserved populations.
FARM LEVEL DEMAND FOR PECANS RECONSIDERED

pecans are price flexible. Prior to 1970, a measure of pecan stocks was unavailable and Previous studies have consistently indi- previous research either ignored stocks or cated the anomalous result of a price inflexrri used the carry-in stocks of all nuts excluding ible demand for pecans. However, these efforts did not have an adequate measure of pecan peanuts as a proxy variable. While this seems did not have an adequate measure of pecan stocks available and, as a result, stocks were tobea "reasonable proxyvariable,theprobeither excluded from consideration or a proxy lem is the ease with which spurious concluvariable was introduced. A time series of sions result from the use of a "reasonable pecan stocks is now available. Use of this proxy variable Empirical researchers fretime series in a price dependent demand quently take liberties along these lines with function results in a flexible farm level de- the hope that spurious conclusions do not mand for pecans. This points out the danger result. This paper serves as a reminder of the of excluding an appropriate variable or using possible consequences of using a model with a so-called "reasonable" proxy variable, estimators that are both biased and incon
Measurement and Prediction of Model-Rotor Flowfields

This paper shows that a laser velocimeter can be used to measure accurately the three-component velocities induced by a model rotor at transonic tip speeds. The measurements, which were made at Mach numbers from 0.85 to 0.95 and at zero advance ratio, yielded high-resolution, orthogonal velocity values. The measured velocities were used to check the ability of the ROT22 full-potential rotor code to predict accurately the transonic flow field in the crucial region around and beyond the tip of a high-speed rotor blade. The good agreement between the calculated and measured velocities established the code's ability to predict the off-blade flow field at transonic tip speeds. This supplements previous comparisons in which surface pressures were shown to be well predicted on two different tips at advance ratios to 0.45, especially at the critical 90 deg azimuthal blade position. These results demonstrate that the ROT22 code can be used with confidence to predict the important tip-region flow field, including the occurrence, strength, and location of shock waves causing high drag and noise.
Master Technology Teacher: A Partnership Between Preservice and Inservice Teachers and Teacher Educators

Technology has permeated our educational experiences from electronic mail to virtual field trips by way of the Internet. As educators seek viable ways to use technology to enhance teaching and learning experiences, colleges must also prepare future teachers to plan for effective technology use. Teacher preparation programs should not only integrate technology throughout the curriculum, but should also provide opportunities for the students to manage problems within the actual school setting as they integrate various tools of technology.
Decoding genetics and molecular biology: Sharing the movies in our heads

For three biology professors, visualizing molecular processes is central to thinking in their discipline. This chapter reports their attempts at getting students to make this same cognitive move and the results of their assessments.
Targeted perinatal drug screening in a rural population

The objectives of this study was to evaluate the efficacy of a risk factor-based drug screening program in a rural perinatal population with a low prevalence of substance abuse. The study was done at a university-based children's hospital in central Missouri. A risk factor-based meconium and infant urine drug screening program was compared to a universal meconium screening program in a newborn population over a 3 month period. Eighteen percent of the 462 deliveries met criteria for drug testing. Of those tested, 11/85 (12.9%) tested positive for marijuana (n = 8) or cocaine (n = 3), representing a detection rate of 2.4% of the total population. This compares well to the 2.6% detected in the universal testing protocol. In three patients, meconium analysis detected marijuana exposure, while urine analysis revealed no detectable drug. Risk factor-based meconium drug screening can identify most infants exposed to illicit drugs in rural perinatal populations with low baseline substance abuse rates. Meconium sampling is more likely than urine sampling to identify exposed infants.
Measurements of Skin Friction of the Compressible Turbulent Boundary Layer on a Cone with Foreign Gas Injection

Measurements of average skin friction of the turbulent boundary layer have been made on a 15deg total included angle cone with foreign gas injection. Measurements of total skin-friction drag were obtained at free-stream Mach numbers of 0.3, 0.7, 3.5, and 4.7 and within a Reynolds number range from 0.9 x 10(exp 6) to 5.9 x 10(exp 6) with injection of helium, air, and Freon-12 (CCl2F2) through the porous wall. Substantial reductions in skin friction are realized with gas injection within the range of Mach numbers of this test. The relative reduction in skin friction is in accordance with theory-that is, the light gases are most effective when compared on a mass flow basis. There is a marked effect of Mach number on the reduction of average skin friction; this effect is not shown by the available theories. Limited transition location measurements indicate that the boundary layer does not fully trip with gas injection but that the transition point approaches a forward limit with increasing injection. The variation of the skin-friction coefficient, for the lower injection rates with natural transition, is dependent on the flow Reynolds number and type of injected gas; and at the high injection rates the skin friction is in fair agreement with the turbulent boundary layer results.
Conducting Polymer and Conducting Composite Strain Sensors on Textiles

Metallic connections and polymer sensors have been printed onto textiles as a step toward the production of flexible printed electronics. We show that the strain response of conducting polymers and composites on woven textiles depends on the detailed distribution the sensor material on the yarn. The structure of most textiles, with strong fibers twisted into yarns, can provide a support which allows electronic materials, impregnated into the yarn, to stretch and bend without breaking.
The occurrence and alleviation by surfactants of soil-water repellency on sand-based turfgrass systems

Even with routine irrigation, soil water-repellency on sand-based turfgrass systems can occur. This study evaluated three commercially available surfactants alone or in combination in 1996, four experimental surfactant formulations in 1997, and four commercially available surfactants and one experimental surfactant in 1998 for their effect on reducing soil-water repellency in mature Cynodon dactylon X Cynodon transvaalensis cv. Tifdwarf sand-based greens. The treatments in 1996 were a commercial standard AquaGro (AG), and two new products, Primer (P) and Aqueduct (AD), applied as liquids at the rates 250, 190 and 250 ml per 100 m 2 , respectively, and a control. Combination treatments of P + AG, and P + AD were also applied at standard rates. Surfactants were evaluated for their effect on turfgrass quality and percent dry spot incidence through a period of drought that induced soil-water repellency symptoms and subsequently through a period of recovery. Water drop penetration time (WDPT). on the soil cores were determined. Data were analyzed for statistical significance (P < 0.05) by automated ANOVA procedures. Results in 1996 demonstrated that during a period of drought, P or AD generally provided both significantly (P < 0.05) higher turfgrass quality and reduced percent dry spotting than AG and the control. Primer or AD significantly (P < 0.05) reduced WDPT. Furthermore, during a recovery period following the drought. P or AD provided significantly (P < 0.05) higher turfgrass quality than untreated controls. Combinations of P + AG or P + AD did not provide significantly higher quality turfgrass or less percent dry spots than individua applications of either P or AD. The second experiment in 1997 consisted of four experimental surfactant formulations of (ACA 1257, ACA 1313, ACA 1455, and ACA 1457), and a control applied at the recommended rate of 250 ml per 100 m 2 , weekly, to plots. As in 1996, surfactants were visually evaluated for turfgrass quality and percent dry spot incidence and soil cores for WDPT. Results demonstrated that ACA treatments generally provided significantly (P < 0.10) higher turfgrass quality and reduced percent dry spotting than the untreated control In 1998, for the third experiment, on a green with extensive soil-water repellency, AD,P, Cascade, LescoFlo, and an experimental surfactant (N-07/05) were applied to alleviate soil water repellency symptoms. The four commercially available surfactants performed well and provided statistically equivalent (P < 0.01) and better turfgrass quality and percent dry spot reduction than the untreated control. The N-07/05 treatment improved turfgrass quality and reduced dry spots compared to the untreated plots as well, but on most dates did not perform as well as the commercial standards.
Recovery technique for saturated masers

The practical application of masers is often hindered by saturation effects of the maser material. Any strong signal frequency (e.g., the transmitter pulse of a radar system leaking into the maser) will cause saturation. This paralyzes the maser for a period of time, too long for most intended applications. In this report, a method is described which has been used in desaturating a four-level ruby maser. The saturation is caused by equalizing the populations of levels one, two, and three of the maser crystal by the leakage of the transmitter pulse, in addition to the action of the maser pump. The application of a desaturation pulse between levels one and four will then desaturate the maser restoring the excess population density between levels two and one. In a cavity maser, full recovery of the amplification capabilities has been achieved within less than 1 msec after the maser has been saturated. Repetition rates up to 120 cps are tolerable.
Delayed treatment with an LTD4/E4 antagonist limits pulmonary edema in endotoxic pigs

We used a selective leukotriene (LT) D4/E4 receptor antagonist (LY 203647) to investigate the role of cysteinyl LTs as mediators of several important pathophysiological events in a porcine model of endotoxic shock. Pentobarbital-anesthetized pigs (11.8-17.5 kg) were mechanically ventilated with 100% O2. Pigs in groups I (n = 10), IIA (n = 10), and IIB (n = 5) were infused with Escherichia coli lipopolysaccharide (LPS; 250 micrograms/kg) from time (t) = 0-20 min. Pigs in group III (n = 3) were normal controls. All pigs were resuscitated from t = 0-240 min with Ringer lactate (0.8 ml.kg-1.min-1). Pigs in group I received no further treatment. At t = 30 min, groups IIA and IIB were injected with LY 203647 (30 mg/kg) and were started on an infusion of the compound at 10 (group IIA) or 30 mg.kg-1.h-1 (group IIB). Delayed treatment with LY 203647 significantly (P less than 0.05) and persistently ameliorated LPS-induced pulmonary hypertension. The compound also abrogated LPS-induced pulmonary edema, as assessed by gravimetrically determined lung extravascular wet-to-dry weight ratios. Despite its beneficial effect on pulmonary edema, delayed treatment with LY 203647 did not improve arterial oxygenation. Delayed treatment with LY 203647 transiently improved mesenteric perfusion. These data suggest that cysteinyl LTs are important mediators in porcine endotoxicosis.
The Energy Release Rate for Decohesion in Thin Multilayered Films on Substrates

The strain energy release rates for the converging decohesion crack in a multilayered film on a substrate have been calculated using the finite element method. The results for the energy release rate as a function of the intrinsic stress, the thickness of the superlayer and the modulus ratio will be presented. A simple functional form for the results will be shown. The effects of plasticity of the thin metal layer on the energy release rate have been examined. The results show that the effect of plastic deformation is not significant for the converging decohesion crack. The effects of the line width have also been addressed. The results show that for two-layer films the energy release rate for steady-state decohesion cracks decreases dramatically as B/h decreases, in the range B/h<40, where B is the line width and h is the thickness of the superlayer. For narrow lines the plane strain solutions overestimate the energy release rate. The numerical results are consistent with the experimental observations on lines with different width.
The Ethics of Tax Evasion: An Empirical Study of Utah Opinion

The present paper is an empirical study, the goal of which is to determine the strength of the various arguments that have been used to justify tax evasion over the last 500 years. A survey was constructed using a seven-point Likert scale that included all three positions and all 18 arguments and distributed to 638 students at a large college in the western United States. The 18 arguments were ranked in terms of strength, from strongest to weakest. Comparisons were also made between male and female responses and between majors.