cssi/SciSciGPT-SciSciNet huggingface dataset:
CHANGES IN GENDER EARNINGS DIFFERENTIALS IN BULGARIA'S TRANSITION TO A MIXED-MARKET ECONOMY

Early theorists predicted that women would bear the brunt of the transition from central planning to mixed market economies in East Central Europe (ECE) and the former Soviet States [Fong and Paull, 1993; Sziraczki and Windell, 1992; Einhorn, 1993]. It was expected that liberalizing the centrally determined wages would increase inequality between men and women. Dismantling the system of extensive social benefits established to promote equality and encourage female labor force participation coupled with the privatization of childcare would increase the costs of participating in the labor market. Furthermore, labor shedding was expected to hit industries with a high concentration of female workers first and hardest, leading to high unemployment rates among women. Evidence from the early transition, however, suggests that women in some transitioning economies have actually improved their economic position relative to men despite rising overall earnings inequality throughout the region [Rutkowski, 1996]. In 1986 the average female worker in Bulgaria earned about 74 percent as much per month as the average male worker. By 1993, the monthly earnings differential between men and women decreased by almost six percent. The goal of this essay is to account for the decline in the gender earnings gap in Bulgaria’s early transition within the broader context of the wage structure changes documented in transitioning economies. In particular, the analysis distinguishes between the portion of the decreased gender earnings gap caused by “group-specific” factors from the component caused by changes in the structure of wages, where “groupspecific” factors represent the degree to which differences in skills between men and women or group differences in industry participation contribute to the decline in the earnings gap. “Wage-structure” factors describe the institutional context in which wages are determined and consist of the portion of the gap explained by changes in skill prices (such as returns to education or returns to working in a particular industry) and changes in the overall level of inequality in an economy. The empirical research relies on cross-sectional survey data from 1986 and 1993. This allows for a comparison between pre- and early-transition Bulgaria, because the initial measures of the economic reform were implemented in 1991 when prices and wages were liberalized. The 1986 survey is the only existing pre-transition survey from Bulgaria and enables an analysis of the heretofore unexplored Bulgarian wage structure prior to 1989. The change in the earnings differentials between 1986 and
A Reification of a Strategy for Geometry Theorem Proving

This study addresses a novel technique to build a graphical user interface (GUI) for an intelligent tutoring system (ITS) to help students to learn geometry theorem proving with construction - one of the most challenging and creative parts of elementary geometry. Students’ task is not only to prove theorems, but also to construct missing points and/or segments to complete a proof (called auxiliary lines). The problem space of theorem proving with construction is generally huge, thus understanding a search strategy is a key issue for students to succeed in this domain. Two major challenges in building a GUI for an intelligent learning environment are (a) to build a theorem prover that is capable of construction, and (b) to establish a cognitive model of understanding a complex problem-solving strategy.
Unique signal transduction of Eyk: Constitutive stimulation of the JAK-STAT pathway by an oncogenic receptor-type tyrosine kinase

The proto-oncogene c-eyk, the cellular counterpart of a transforming oncogene, v-eyk, encodes a receptor protein tyrosine kinase with a distinctive extracellular region. We now demonstrate that c-Eyk can be constitutively activated through dimerization, and that the active Eyk displays a unique signaling pattern. When the kinase domain of c-Eyk was fused to the extracellular and transmembrane domains of CD8, the resulting chimera showed elevated kinase activity and caused cellular transformation. We found that the activated Eyk kinases, both v- and c-Eyk, constitutively stimulate the JAK-STAT pathway, while exerting little effect on other signaling routes such as the Ras-MAP kinase and the JNK pathways. The activated Eyk kinases specifically stimulate tyrosine phosphorylation of STAT1, STAT3 and JAK1. These downstream molecules also co-immunoprecipitate with the constitutively dimerized form of Eyk. The Eyk kinase activity is required for STAT1 stimulation. We found that the activation of STAT1 but not STAT3 correlates well with cellular transformation. In constitutively stimulating the JAK-STAT pathway, particularly STAT1, Eyk is unique in its downstream signaling and may be dependent on this pathway for cellular transformation.
A Smoothness Indicator for Adaptive Algorithms for Hyperbolic Systems

The formation of shock waves in solutions of hyperbolic conservation laws calls for locally adaptive numerical solution algorithms and requires a practical tool for identifying where adaption is needed. In this paper, a new smoothness indicator (SI) is used to identify “rough” solution regions and is implemented in locally adaptive algorithms. The SI is based on the weak local truncation error of the approximate solution. It was recently reported in S. Karni and A. Kurganov, Local error analysis for approximate solutions of hyperbolic conservation laws, where error analysis and convergence properties were established. The present paper is concerned with its implementation in scheme adaption and mesh adaption algorithms. The SI provides a general framework for adaption and is not restricted to a particular discretization scheme. The implementation in this paper uses the central-upwind scheme of A. Kurganov, S. Noelle, and G. Petrova, SIAM J. Sci. Comput.23, 707 (2001). The extension of the SI to two space dimensions is given. Numerical results in one and two space dimensions demonstrate the robustness of the proposed SI and its potential in reducing computational costs and improving the resolution of the solution.
InterPol: a policy framework for managing trust and privacy in referral networks

Referral networks are a kind of P2P system consisting of autonomous agents who seek, provide services, or refer other service providers. Key applications include service discovery and selection, and knowledge sharing. This use of referrals is inspired by human interactions, where referrals are a key basis for judging the trustworthiness of a given service.The use of referrals enable an agent to control how its request is processed, it also provides an architectural basis for four kinds of interaction policies. InterPol is a language and framework supporting such policies. InterPol has been implemented using a Datalog-based policy engine for each agent. It has been applied on scenarios from a (multinational) health care project. The contribution of this paper is in a general referrals-based framework for privacy and trust management, which is shown to effectively capture a variety of privacy and trust requirements of autonomous users.
Parents’ Weekly Descriptions of Autonomy Supportive Communication: Promoting Children’s Motivation to Learn and Positive Emotions

Although parental autonomy support has been linked to children’s intrinsic motivation to learn and positive emotions in numerous studies, there has been little research on interventions to promote parental autonomy support, especially in the realm of homework and school related learning. Furthermore, there are relatively few qualitative studies dealing with parent autonomy support and children’s emotional responses. This qualitative study examined the weekly journals of 15 parents who were learning how to promote autonomous motivation and academic enjoyment among their 4th and 5th grade children via autonomy supportive communication. Four themes emerged: generalization beyond homework and school-related learning; parents occasionally misinterpreting what it means to be autonomy supportive; strong positive responses, such as children enjoying homework and becoming more passionate about learning; and parent–child shared enjoyment and persistence in the educational games that were provided as a way to practice the autonomy supportive parenting style during each week of the intervention. This study provides insight into how parents actually apply autonomy supportive parenting techniques in the home environment. Future related parent education may benefit from these findings; for instance, parents may be provided with more examples of how autonomy support can generalize to learning in various domains of life, such as mastering a musical instrument, attending a museum exhibit, ordering books for reading pleasure and learning how to operate a boat safely. Interventions that promote children’s autonomous motivation to learn and enjoyment of learning through parental autonomy support should be further developed and studied.
Science teacher educators’ opinions about science projects and science fairs

(1995). Science teacher educators’ opinions about science projects and science fairs. Journal of Science Teacher Education: Vol. 6, No. 1, pp. 48-52.
Semantic category imprecision: a connectionist study of the boundaries of word meanings.

Abstract The view that word meanings have a discrete symbolic character has led to misleading impressions about their neurobiological basis. We hypothesize that this lexical semantic knowledge is imprecise, overlapping, and widely distributed throughout the human temporal lobes. The present study uses a computer modeling experiment to investigate this hypothesis. The objects in the study are “cups” and “bowls.” Thirty connectionist networks were taught that wide containers without handles are “bowls” and that narrow containers with handles are “cups.” The network was then asked to identify 14 different cylindrical containers of seven different widths, some with handles and others without. When compared to a study of human performance, the networks manifested the normal pattern of object naming and the normal pattern of individual variability.
Electroencephalographic Evidence for Residual CNS Hyperexcitability During Cocaine Abstinence

The author evaluated visual steady-state evoked responses (SSER) and auditory amplitude-modulated following responses (AMFR) in 13 cocaine-dependent patients, 5 alcohol-dependent patients, and 12 non-drug-dependent control subjects. The 18 patients were studied after 1, 3, and 12 weeks of verified abstinence; the controls were studied after comparable intervals. Analyses revealed that visual SSER power increased as a function of modulation depth in the cocaine-dependent group, but not in the other groups. The difference among the groups was greatest at the highest modulation depth (80%) and did not diminish over time. Auditory AMFR power was also greater in the cocaine-dependent group relative to the other groups. However, unlike the visual SSER, the auditory AMFR normalized with continued cocaine abstinence. Collectively, the SSER and AMFR findings are interpreted as reflecting a residual cocaine effect which heightens CNS reactivity to sine wave (but not square wave)-modulated visual and auditory input.
Structural transitions of satellite tobacco mosaic virus particles.

Satellite tobacco mosaic virus (STMV) can undergo at least two physical transitions that significantly alter its mechanical and structural characteristics. At high pH the 17-nm STMV particles expand radially by about 5 A to yield particles having diameters of about 18 nm. This pH-induced transition is further promoted by aging of the virions and degradation of the RNA, so that swollen particles ultimately appear even at neutral pH. While the native 17-nm particles crystallize as orthorhombic or monoclinic crystals which diffract to high resolution (1.8 A), the enlarged 18-nm particles crystallize in a cubic form which diffracts to no better than 5 A. In the transition, not only do the capsid protein subunits move radially outward, but the helical RNA segments with which they interact do as well. This is noteworthy because it demonstrates that the RNA and the protein shell are capable of coordinated movement, and that neither structure is rigidly defined or independent of the other. Using atomic force microscopy, it can be shown that STMV particles, upon drying, lose their mechanical rigidity and undergo deformation. Virions initially 17 nm in diameter shrink to more uniform final sizes than do 18 nm, initially swollen particles. This transition appears to be irreversible, as the particles do not reassume their former size nor structural rigidity upon rehydration. Evidence is also presented that preparations of native virus and their crystals are naturally somewhat heterogeneous and contain a variety of particles of anomalous size.
INFORMATION PROCESSING VS VISUAL. ATTENTION DURING INCIDENTAL LEARNING

The relationship between attention and incidental learning during discrimination training was studied in 30 children, aged 10 to 11. A polymetric eye-movement recorder measured direct visual attention. Consistent with previous findings, recall of incidental stimuli was greatest during the initial and terminal stages of intentional learning. Contrary to previous explanations, however, visual attention to incidental stimuli was not related to training. While individual differences in attention to incidental stimuli were predictive of recall, attention to incidental stimuli was not related to level of training. Results suggested that changes in higher order information processing rather than direct visual attention were responsible for the curvilinear learning of incidental stimuli during intentional training.
Influence of Electrolyte Activity on Formal Potentials Measured for Ferrocenylhexanethiol Monolayers on Gold: Indistinguishable Responses in Aqueous Solutions of HClO4 and NaClO4

A detailed study of the influence of electrolyte activity on apparent formal potentials measured for self-assembled monolayers of ferrocenylhexanethiol at high coverages on gold electrodes is provided. Ion selective electrodes are used in a logical sequence of comparisons to eliminate liquid junction potentials and, ultimately, to provide a rigorous comparison of apparent formal potentials for the monolayer over a broad range of concentrations in aqueous solutions of HClO4 and NaClO4. The results obtained in HClO4 and NaClO4 solutions are indistinguishable. Under the conditions examined it appears that protons and sodium ions have little influence on the apparent formal potentials. Hence it seems that protons and sodium ions have little influence on the overall interfacial potential distribution and, thus, little influence on the overall ionic structure near the monolayer/solution interface. The picture that emerges for the oxidized “monolayer” is one in which the high surface charge produced by the high ...
Respiratory failure due to achalasia cardia

Summary A 76-year-old male was seen in our hospital for hypoxic respiratory failure and bronchorrhea worsening over a few weeks. He failed treatment with antibiotics and diuretics. A CT scan of the chest was performed which revealed a dilated esophagus with an air-fluid level with evidence of aspiration. A contrasted upper GI series revealed typical “birds beak” appearance of achalasia. He was treated with botulinum injections into lower esophageal sphincter and his hypoxemia resolved. Achalasia is a lesser known cause of aspiration which can lead to respiratory failure. We have discussed the wide spectrum of aspiration syndromes seen in the setting of various swallowing disorders.
Residency and fellowship training in radiology: survey of all United States programs.

Rationale and Objectives. We surveyed radiology training programs to determine current requirements for a clinical internship year, recent changes in the clinical internship requirement, current number of residents, percentage of residents with preradiology clinical experience, number of current first-year fellows, and percentage of residents entering fellowships. Methods. Survey forms were sent to all 208 U.S. diagnostic radiology programs and were followed up by telephone and facsimile transmission. Results. Survey response rate was 100%. One hundred programs (48%) require an internship, whereas 108 programs (52%) do not. Of programs without a clinical internship requirement, 33 (31%) have eliminated this requirement within the last 5 years. The clinical year requirement varied greatly by region. A total of 3983 residents are training at present, and 29% did not complete a clinical internship. Currently, 650 fellows are in training. Approximately 68% of graduating residents are entering fellowships. Conclusions. Many residency programs have recently discontinued the clinical internship year requirement. Changes in Medicare reimbursement of resident salaries may be one factor promoting this change. During the past 4 years, the number of radiology residents training per year has increased. The percentage of residents entering radiology without an internship year has increased by 6% during the past 4 years. An increasing number of graduating residents are entering fellowships.
Performance Analysis of a Target Detection System Using Infrared Imagery

The automatic detection of targets in cluttered infrared imagery is considered. The environment for the problem is that of a "fire-and-forget" weapon, and the mission philosophy for such a weapon dictates that the weapon has to find one and only one target in the automatic detection phase. A detection system that meets this requirement is presented. The system uses techniques of image processing and pattern recognition, with the extension that ranking methods are used instead of thresholds to accommodate the requirement of finding one and only one target. A probability model of the system is developed to determine the system performance as a function of throughput and expressions derived for the probability that the object chosen by the system as the target is actually a target. In order to validate the theoretical results, the actual performance of the detection system on a database of 68 infrared images is determined and compared with the predicted performance of the system. It is shown that there is good correspondence between the empirical results and the theoretical performance.
Thermodynamic β-sheet propensities measured using a zinc-finger host peptide

THE three-dimensional structures of proteins reveal that the distribution of amino acids within the major classes of secondary structure is not random but that each amino acid has its own preferred secondary structural arrangements1–5. Propensity scales for residues in α-helices have been generated through the use of various host-guest systems6–9. Here we measure the thermo-dynamic β -sheet propensities of each of the twenty commonly occurring amino acids. A previously studied zinc-finger peptide10 was used as the host system in which amino acids were substituted into a guest site, a solvent-exposed position in an antiparallel β -sheet. As these peptides are unfolded in the absence of bound metal but are folded in their presence, it is assumed that the thermodynamics of metal binding fully reflect peptide-folding energy. A competitive cobalt(II)-binding assay was used to determine these energies with high precision. The relative free energies correlate well with previously derived potential values based on statistical analysis of protein structures. We are therefore able to present a thermodynamic β -sheet propensity scale for all the commonly occurring amino acids in aqueous solution.
Catalytic effects of methane/air and propane/air mixtures using a platinum catalyst in a stagnation point flow configuration

A stagnation-point flow burner facility has been developed to provide a canonical framework to study the catalytic surface reactions of premixed combustion systems. The configuration serves as an important platform to investigate the interaction between homogeneous and heterogeneous reactions with an independent control of the characteristic residence time scales. Methane/air, and propane/air mixtures were examined with or without the presence of a platinum catalyst located at the stagnation surface. The effects of oxidizer composition and nitrogen dilution were examined. Depending on the operating conditions, either a stable gas-phase flame is established between the nozzle and the stagnation surface or the unburned reactant mixture directly impinges on the heated surface. In the former case, the extinction limits of the gas-phase flame were measured for various equivalence ratios and flow conditions. In the latter case, the heat release resulting from the surface reaction was quantified by measuring the surface temperature of the stagnation plate. The results are discussed in terms of the relative contributions of the gas-phase and the surface reaction chemistry to the burner performance. Understanding gained from this study will provide insights into the role of catalytic reactions in extending the flammability of compact combustors subjected to excessive surface heat loss.© 2007 ASME
Estimation of dynamic asymmetric tail dependences: an empirical study on Asian developed futures markets

In this research, we employ three two-parameter Archimedean copulas (BB1, BB4 and BB7) to investigate the dynamic asymmetric tail dependences between two of three Asian developed futures markets, Hong Kong, Japan and Singapore, during the post-Asian financial crisis period. We first model the marginal distribution by conditional skewed-t distribution and find that higher moments of each filtered index futures return are time dependent. We then extend the two-parameter copulas incorporating time-varying tail dependences to capture the dynamic asymmetries. The estimated results provide strong evidence of asymmetric dependence across the three futures markets. Moreover, to take account of data snooping, we implement Hansen's (2005) superior predictive ability test to evaluate the model fitting. We found that the BB7 copula for the Hang Seng–MSCI SIN (Morgan Stanley Capital International index) pair and the BB1 copula for the Nikkei 225–MSCI SIN pair outperform the simple symmetric Gaussian copula. These best...
Reference Unbound Bilirubin Concentrations in Plasma of Jaundiced Newborns 927

Bilirubin-albumin binding is important in assessing the risk of bilirubin encephalopathy in jaundiced newborns. Although exchange transfusion is recommended at specific bilirubin/albumin (B/A) ratios for babies of various birthweights and illness (Pearlman et. al. Pediatrics. 62:460, 1978), the actual unbound bilirubin (UB) concentrations at these ratios has not been determined. We therefore measured UB in 134 newborns with birthweights between 500 and 4270 g and gestational ages from 24 to 41 weeks to determine UB and its variability at reference B/A ratios. UB was measured at 288 total bilirubin concentrations and sample dilutions of 1:44 using a modified peroxidase test which allowed corrections for rate limiting dissociation of bilirubin from albumin which occurred in 88% of the UB measurements. The babies were grouped by birthweight and gestation and the equilibrium binding constants for each group determined (Klotz and Hunston. Arch Biochem Biophys 193:314, 1979). From these constants, the reference UB's and 95% confidence intervals were calculated at the reference A/B ratios. The data for gestational age are given in the table for High and Standard risk newborns as defined by Pearlman (see above reference).
Effect of fluoxetine, pemoline and placebo on heart period and QT variability in normal humans

Objective: To measure the effects of fluoxetine and pemoline on heart period and QT variability. Methods: Healthy volunteers were randomly assigned treatment with 20 mg daily of fluoxetine (n=7), 56.25 mg of pemoline (n=7) or placebo (n=9). Twenty-four-hour Holter ECGs were obtained before and after approximately 8 weeks of double-blind treatment. Results: There were no significant changes in the fluoxetine group. Pemoline was associated with a significant decrease in the high frequency (HF) power (0.15–0.5 Hz, P=.02) and fractal dimension of RR time series (P=.03). QTvi, a measure of QT interval variability, increased in the pemoline group (P=.05). Conclusion: Pemoline, but not fluoxetine, decreases heart period variability (HPV) in the HF power, suggesting a vagolytic effect on cardiac autonomic function. Pemoline is also associated with an increase in QT interval variability, a measure that is sensitive to adrenergic agonists.
Adsorption of water on graphene/Ru(0001)-an experimental ultra-high vacuum study.

Data for water adsorption on epitaxial graphene grown on Ru(0001) at ultra-high vacuum (clean conditions) are discussed. Accordingly, water adsorption was not affected by the support. The interaction is not strictly hydrophobic. We propose simple rules based on ultra-high vacuum kinetics to classify the water–graphene-support interactions.
Managers as negotiators: A test of power versus gender as predictors of feelings, behavior, and outcomes

Abstract This study explores the impact of gender and power on the feelings, behavior, and outcomes achieved by managerial men and women engaged in an intra-organizational conflict. Forty pairs of practicing managers (40 men and 40 women in same- and mixed-gender pairs) took part in a simulated negotiation in which the parties differed in organizational power. This design permitted the testing of several hypotheses about the direct effects of gender and power, as well as the question of whether gender and power would accumulate to men's advantage and women's disadvantage. Results show that managerial women expressed less confidence and less satisfaction with their own performance than managerial men but did not differ in their behavior or in the outcomes they achieved. High-power managers, of both genders, attempted to engage in cooperative behavior with their partners, and believed they achieved cooperative outcomes. But low-power managers were more competitive and felt they gained their own ends at the expense of the other party. Some interactions between gender and power are suggested by the results, but none of them match predictions from existing theory. Implications and limitations of the study are discussed.
Establishment of the human papillomavirus type 16 (HPV-16) life cycle in an immortalized human foreskin keratinocyte cell line.

The study of human papillomaviruses (HPVs) in cell culture has been hindered because of the difficulty in recreating the three-dimensional structure of the epithelium on which the virus depends to complete its life cycle. Additionally, the study of genetic mutations in the HPV genome and its effects on the viral life cycle are difficult using the current method of transfecting molecularly cloned HPV genomes into early-passage human foreskin keratinocytes (HFKs) because of the limited life span of these cells. Unless the HPV genome transfected into the early-passage HFK extends the life span of the cell, analysis of stable transfectants becomes difficult. In this study, we have used BC-1-Ep/SL cells, an immortalized human foreskin keratinocyte cell line, to recreate the HPV-16 life cycle. This cell line exhibits many characteristics of the early-passage HFKs including the ability to stratify and terminally differentiate in an organotypic raft culture system. Because of their similarity to early-passage HFKs, these cells were tested for their ability to support the HPV-16 life cycle. The BC-1-Ep/SL cells could stably maintain two HPV genotypes, HPV-16 and HPV-31b, episomally. Additionally, when the BC-1-Ep/SL cell line was stably transfected with HPV-16 and cultured using the organotypic raft culture system (rafts), it sustained the HPV-16 life cycle. Evidence for the productive stage of the HPV-16 life cycle was provided by: DNA in situ hybridization demonstrating HPV-16 DNA amplification in the suprabasal layers of the rafts, immunohistochemical staining for L1 showing the presence of capsid protein in the suprabasal layers of the rafts, and electron microscopy indicating the presence of virus like particles (VLPs) in nuclei from cells in the differentiated layers of the rafts.
P2-244: Analyses of the equivalency of different versions of the Mini-Cog™

with dementia of the Alzheimer’s type (AD) and 57 vascular dementia patients (VaD) were interviewed individually. They were asked to report the cognitive, emotional, and physical symptoms of the patients observed in the everyday life. Results: Summarizing a pool of total 299 dementic symptoms that were reported from the family members, 33 items were finally selected as preliminary items for the KDQ. Further analyses that compared AD with VaD based on these 33 items showed that the KDQ could provide valuable information about the diagnostic differentiation and the severity of dementia. Conclusions: These results confirmed the clinical validity and usefulness of KDQ consisting of 33 items that were selected in the present study. It suggests that if normative data were provided from the following study in the healthy elderly, the KDQ can be used effectively as a screening tool for dementia as well as for the staging of dementia.
Nanoparticle SERS substrates with 3D Raman-active volumes

This Perspective reviews a new class of surface-enhanced Raman scattering (SERS) nanoparticle substrates defined by their three-dimensional (3D) confinement of localized electromagnetic fields. First, we describe the critical design parameters and recent advances in nanofabrication to create reproducible nanoparticle assemblies for SERS. Next, we highlight a promising platform—gold nanopyramids—for testing how the local arrangement of particles in an assembly affects the overall SERS response. The dimensions and optical properties of the nanopyramids can be tuned easily, and their unique anisotropic shape allows them to be organized into different particle configurations with 3D Raman-active volumes. Because of their large hot-spot volumes, this unique class of nanoparticle substrates offers an attractive alternative for ultra-sensitive sensors and trace chemical analysis.
Impact of the National History Day in Ohio Program on Students' Performances: Pilot Evaluation Project.

AbstractThis pilot study aimed at developing and validating an evaluation model to assess the impact of participation in the National History Day in Ohio program (NHD-OH) on students academic achievement and intellectual growth by using as key indicators: A) High-stakes tests, i.e., Ohio Graduation Tests (OGT) in Social Studies, Reading and Writing; B) Appreciation of history, and C) Development of critical thinking. Using a quasi-experimental study design, twenty-four tenth-graders participating in NHD-OH and twenty-four matched controls were used in the analysis to reduce the impact of selection bias. As a result of this study it was found that students participating in NHD-OH received statistically significant higher scores on the Social Studies OGT, Reading and Writing; and furthermore, demonstrated a deeper appreciation of history and a better ability to explore and integrate new perspectives.
Long-term voriconazole and skin cancer: is there cause for concern?

Skin toxicity due to voriconazole is well recognized. Recently, several series have reported skin cancer, particularly cutaneous squamous cell carcinoma (C-SCC), following photosensitivity reactions among patients receiving long-term voriconazole (>12 months). Almost all patients were immunosuppressed, including stem cell and solid organ transplant recipients. A case-control study of lung transplant recipients identified long-term voriconazole (median cumulative dose: 76 grams) and residence in areas of strong sun exposure as independent risk factors for C-SCC. The mechanism(s) by which voriconazole may predispose to skin cancer is not clear. Moreover, the relative contribution of voriconazole and other factors such as immunosuppression, ultraviolet exposure, advanced age and skin type is unknown. Until further data are available, voriconazole should be used carefully for durations >6–9 months, particularly among patients with risk factors for skin cancer. In patients requiring prolonged voriconazole, diligent skin examinations, avoidance of excess sunlight, and liberal use of UV protectants are advisable.
Steroid Trime Thylsilyl Ethers

Abstract The silylation of hydroxysteroids has been studied with different silylating reagents, and under non-catalyzed and catalyzed conditions. When BSA alone is used (non-catalyzed reaction), TMSi ether formation does not occur for 11β- and tert-17α-hydroxyl groups. When BSA-TMCS is used (catalyzed reaction), 11β-hydroxyl groups are converted to-TMSi ethers, and tert-17α-hydroxyl groups of the THE-THF series will also react. Complete silylation of all hydroxyl groups for compounds of the cortol series may be effected with TSIM-BSA-TMCS at 60° C.
Three‐Dimensional Model of the Sound Field Surrounding a Rigid Obstacle

Extensive study of the sound field in the region surrounding a rigid obstacle has led to the development of a three‐dimensional representation of the pressure field. The obstacle under investigation was placed in an anechoic chamber in the path of a plane acoustic wave. The sound field in a selected horizontal plane surrounding the obstacle was studied by automatically moving a small probe microphone through the region at a speed of 4 mm/sec. The signal from the probe microphone was fed to an audiofrequency spectrometer and recorded by means of a graphic level recorder. The data tapes were coordinated to construct a three‐dimensional model showing the pressure amplitude as a function of two position coordinates (x and y). Models have been constructed for the sound field in the region surrounding a sphere and a cube at different frequencies. [This work was supported by a Research Grant from Temple University.]
Antibodies specific to acetylated histones document the existence of deposition- and transcription-related histone acetylation in Tetrahymena

In this study, we have constructed synthetic peptides which are identical to hyperacetylated amino termini of two Tetrahymena core histones (tetra-acetylated H4 and penta-acetylated hv1) and used them to generate polyclonal antibodies specific for acetylated forms (mono-, di-, tri-, etc.) of these histones. Neither of these antisera recognizes histone that is unacetylated. Immunoblotting analyses demonstrate that both transcription-related and deposition-related acetate groups on H4 are recognized by both antisera. In addition, the antiserum raised against penta-acetylated hv1 also recognizes acetylated forms of this variant. Immunofluorescent analyses with both antisera demonstrate that, as expected, histone acetylation is specific to macronuclei (or new macronuclei) at all stages of the life cycle except when micronuclei undergo periods of rapid replication and chromatin assembly. During this time micronuclear staining is also detected. Our results also suggest that transcription-related acetylation begins selectively in new macronuclei immediately after the second postzygotic division. Acetylated histone is not observed in new micronuclei during stages corresponding to anlagen development and, therefore, histone acetylation can be distributed asymmetrically in development. Equally striking is the rapid turnover of acetylated histone in parental macronuclei during the time of their inactivation and elimination from the cell. Taken together, these data lend strong support to the idea that modulation of histone acetylation plays an important role in gene activation and in chromatin assembly.
Deposition of aerosol particles in a channel due to diffusion and electric charge

Abstract The diffusion equation and the Poisson equation for flow of aerosol particles with electrostatic charge in a parallel-plate channel were solved with integral method. The inverse of the centerline particle density was found to increase linearly with the product of the electrostatic parameter and the axial distance for the flow near the channel inlet. The centerline particle density, the penetration and the electric field force decreased exponentially with the axial distance for flow far from the channel inlet. The analysis was based on flow of liquid with uniform and parabolic velocity profiles. Results were presented in figures.
Effects of recombinant precursor pathway variations on poly((R)-3-hydroxybutyrate) synthesis in Saccharomyces cerevisiae

Different recombinant R-3-hydroxybutyryl-CoA (3-HB) synthesis pathways strongly influenced the rate and accumulation of the biopolymer poly[(R)-3-hydroxybutyrate] (PHB) in Saccharomyces cerevisiae. It has been previously shown that expression of the Cupriavidus necator PHB synthase gene leads to PHB accumulation in S. cerevisiae [Leaf, T., Peterson, M., Stoup, S., Somers, D., Srienc, F., 1996. Saccharomyces cerevisiae expressing bacterial polyhydroxybutyrate synthase produces poly-3-hydroxybutyrate. Microbiology 142, 1169-1180]. This finding indicates that native S. cerevisiae expresses genes capable of synthesizing the correct stereochemical substrate for the synthase enzyme. The effects of variations of 3-HB precursor pathways on PHB accumulation were investigated by expressing combinations of C. necator PHB pathway genes. When only the PHB synthase gene was expressed, the cells accumulated biopolymer to approximately 0.2% of their cell dry weight. When the PHB synthase and reductase gene were co-expressed, the PHB levels increased approximately 18 fold to about 3.5% of the cell dry weight. When the beta-ketothiolase, reductase and synthase genes were all expressed, the strain accumulated PHB to approximately 9% of the cell dry weight which is 45 fold higher than in the strain with only the synthase gene. Fluorescent microscopic analysis revealed significant cell-to-cell heterogeneity in biopolymer accumulation. While the population average for the strain expressing three PHB genes was approximately 9% of the cell dry weight, some cells accumulated PHB in excess of 50% of their cell volume. Other cells accumulated no biopolymer. In addition, the recombinant strain was shown to co-produce ethanol and PHB under anaerobic conditions. These results demonstrate that the technologically important organism S. cerevisiae is capable of accumulating PHB aerobically and anaerobically at levels similar to some bacterial systems. The easily assayed PHB system also creates a convenient means of probing in vivo the presence of intracellular metabolites which could be useful for studying the intermediary metabolism of S. cerevisiae.
Integrating principles of developmental biology in tissue engineering of heart valves.

Approximately eight out of every thousand infants are born with congenital heart disease. The majority of these defects involve malformations or absence of the pulmonary valve and main pulmonary arteries. Although repair early in life is possible, the procedure often requires the use of a replacement valve. Current replacement options include prosthetic and bioprosthetic valves; however, these replacements have limited durability and are subject to calcification, thrombosis and a lack of growth potential [1]. Children, therefore, face an ongoing morbidity due to the limitations of these replacement valves and must endure multiple follow-up operations in order to place progressively larger valves to accommodate their growth. Tissue engineering offers the potential to create a living valve with the capacity for growth and self-repair, and which is resistant to infection. Tissue engineering is defined as an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain or improve function [2]. This approach is based on seeding autologous cells onto biodegradable scaffolds or decelullarized biological matrices in order to provide temporary structural support and organization until the cells synthesize their own extracellular matrix. Previous studies by our group and others have demonstrated in vivo results culminating in the creation of single-valve leaflets [3], vascular grafts [4,5] and trileaflet-valved conduits [6–11]. These tissue-engineered heart valve (TEHV) structures have been created using vascular cells [3,4,6–9], umbilical bloodderived endothelial progenitor cells [11] and noncirculating bone marrow-derived mesenchymal stem cells [12,13] as cell sources. Our group and others have also demonstrated results in preliminary in vivo experiments. However, many questions remain unanswered: • What is the optimal cell source? • How will the scaffold material influence tissue growth and allow favorable scaffold cell and extracellular matrix interactions? • What in vitro conditions provide the most cell growth? • What is the timeframe for in vivo maturation? The ideal heart valve replacement would not only be biocompatible, readily available and incredibly durable, but also have the potential for growth [14]. Although the ultimate goal of TEHV is to recapitulate the matrix and cells found in the native tissue, variabilities exist within the potential strategies and sources of cells. A widely accepted paradigm of tissue engineering comprises of a scaffold that is preseeded with cells, followed by an in vitro stage of tissue formation typically conducted in a bioreactor (that recapitulates a physiological metabolic and mechanical environment) and, following subsequent implantation of the construct, an in vivo stage of tissue growth and remodeling [15].
Regional shape-based feature space for segmenting biomedical images using neural networks

In biomedical images, structure of interest, particularly the soft tissue structures, such as the heart, airways, bronchial and arterial trees often have grey-scale and textural characteristics similar to other structures in the image, making it difficult to segment them using only gray- scale and texture information. However, these objects can be visually recognized by their unique shapes and sizes. In this paper we discuss, what we believe to be, a novel, simple scheme for extracting features based on regional shapes. To test the effectiveness of these features for image segmentation (classification), we use an artificial neural network and a statistical cluster analysis technique. The proposed shape-based feature extraction algorithm computes regional shape vectors (RSVs) for all pixels that meet a certain threshold criteria. The distance from each such pixel to a boundary is computed in 8 directions (or in 26 directions for a 3-D image). Together, these 8 (or 26) values represent the pixel's (or voxel's) RSV. All RSVs from an image are used to train a multi-layered perceptron neural network which uses these features to 'learn' a suitable classification strategy. To clearly distinguish the desired object from other objects within an image, several examples from inside and outside the desired object are used for training. Several examples are presented to illustrate the strengths and weaknesses of our algorithm. Both synthetic and actual biomedical images are considered. Future extensions to this algorithm are also discussed.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Transient elastodynamic analysis of three‐dimensional problems by boundary element method

An advanced implementation of the direct boundary element method applicable to transient problems involving three-dimensional solids of arbitrary shape and connectivity is presented. The work first focuses on the formulation of the method, followed by a discussion of the fundamental singular solutions. Subsequently, a family of isoparametric boundary elements is introduced, along with the necessary numerical integration techniques as well as the solution algorithm. Numerical examples are presented, which demonstrate the unconditional stability and high accuracy of this dynamic analysis technique.
Digital processing of contrast echocardiograms: A new technique for measuring right ventricular ejection fraction

Imaging of the right ventricle with 2-dimensional echocardiography (2-D echo) is hampered by trabeculation of the right ventricular (RV) endocardial surface and by limited echocardiographic resolution. Determination of RV ejection fraction (EF) is thus often an inconsistent and tedious procedure. The process of digital subtraction contrast echocardiography was developed to maximize echocardiographic definition of the right ventricle and to assess RVEF with minimal operator interaction. Videotaped 2-D echocardiograms recorded during i.v. injection of agitated saline were digitized. Masks were constructed from end-systolic and end-diastolic apical 4-chamber and parasternal RV short-axis images. Masks were subtracted from corresponding images recorded with contrast in the right ventricle; images of the contrast alone were extracted and their areas determined. EF was calculated from raw area measurements and after conversion to volume. Comparison with RVEF measured by first-pass radionuclide angiography yielded the following correlation coefficients: 4-chamber RV area, r = 0.79; parasternal short-axis RV area, r = 0.59; ellipsoid approximation RV volume, r = 0.84; pyramidal RV volume, r = 0.79; and Simpson's rule triangular cylinder RV volume, r = 0.62. Digital subtraction contrast echocardiography is a new method that can be used for semiautomated determination of RVEF. Further studies to assess the clinical values of digital image processing of 2-D echocardiograms to measure RV function appear warranted.
Chironomidae from marine coastal environments near St. John's, Newfoundland, Canada

Chironomid larvae and adults were collected from rock pool and intertidal sites between 1990 and 1994 on the exposed Atlantic coast and in more sheltered bays near St. John's. From several thousand specimens collected, 16 chironomid taxa were identified. Two were from intertidal habitats and the remainder occurred in rock pools. In intertidal habitats Halocladius variabilis was abundant in summer among clumps of fine filamentous algae, e.g. Pilayella littoralis. The previous Nearctic records of this chironomid were from Hudson Bay and Greenland although it is widespread in northern Europe. The other intertidal species, Telmatogeton japonicas, was recorded from one site, a rock outcrop on a beach in the mouth of a small stream. This Holarctic species has not been reported previously north of New York on the Atlantic coast. The rock-pool communities were dominated by Psectotanypus dyari, Cricotopus sylvestris, Psectocladius sordidellus gp, Orthocladius dubitatus, Chironomus riparius, and Tanytarsus sp. These taxa are known to tolerate sites with elevated salinity and/or conductivity and thus are present in polluted sites inland. The other eight chironomid species were rare and most were found at only one site. An exception was the Metriocnemus sp. collected in very low numbers at three sites and also collected previously during a survey of rock pools for larval mosquitoes in the same area. The current study shows that a diverse coastal chironomid community is present in the cold ocean habitats of eastern Newfoundland. The community is made up of both arctic and temperate faunal elements with widespread distributions not confined to coastal habitats. Ranges of temperature, salinity, conductivity and pH for the common species occurring in the rock pools are provided. The results suggest that coastal rock pool habitats could be a natural laboratory for studies on the evolutionary ecology of pollution tolerance in chironomids.
Thank God for Evolution: How the Marriage of Science and Religion Will Transform Your Life and Our World

Michael Dowd Thank God for Evolution: How the Marriage of Science and Religion Will Transform Your Life and Our World New York: Viking, 2007. 448 pp. $16.00 ISBN 978-0-670-02045-4 Coffee hour at th...