cssi/SciSciGPT-SciSciNet huggingface dataset:
EFFECTS OF DIETHYLSTILBESTROL AND MAGNESIUM ON THE RAT OXYTOCIC POTENCIES OF SOME NEUROHYPOPHYSIAL HORMONES AND ANALOGUES.

Precise in vitro oxytocic potencies of synthetic oxytocin, arginine vasotocin, arginine vasopressin and deamino-oxytocin were obtained from metestrous or diestrous rats and from diethylstilbestroltreated rats. In each of the 2 endocrine conditions, van Dyke-Hastings solution with 0.5 mM Mg or no magnesium was used to bathe the uterus. Four oxytocic potencies were therefore obtained for each peptide. Both estrogen and magnesium usually influenced potency significantly. Alterations of potency by these 2 factors appeared to vary independently from one another. The most consistently useful and sensitive rat uterus is one treated with diethylstilbestrol and bathed in a solution containing magnesium ion. {Endocrinology 76: 90, 1965) T IN VITRO rat oxytocic potencies of several highly purified neurohypophysial hormones and analogues were previously determined with 0.0 and 0.5 mM Mg++ in van Dyke-Hastings solution (1). The ratio, Potency, USP U/mg in 0.5 HIM Mg++ Potency, USP U/mg in 0.0 HIM Mg++' RMK++, was greater than 1.0 for the following peptides: 8-arginine vasopressin (1.6), 8-arginine oxytocin (arginine vasotocin) (1.9), 3-phenylalanine oxytocin (oxypressin) (1.4), 2-phenylalanine oxytocin (2.9), 8-lysine vasopressin (2.6), and 3-valine oxytocin (3.6). Oxytocin was the sole substance assayed whose potency was not significantly augmented by the presence of magnesium. Although responses to oxytocin were increased by magnesium, they were less potentiated than the responses to other peptides. Arginine vasopressin and oxytocin are both present in the USP Posterior Pituitary Reference Standard. Magnesium Received June 23, 1964. Supported in part by grants in aid from the National Institutes of Health (HD-00589); Fluid Research Fund, University of Colorado Medical Center; and Sandoz Pharmaceuticals, Inc., San Francisco, California. potentiates responses to the vasopressin far more than to the oxytocin. Therefore, in assaying against this mixed standard, which is more potentiated than oxytocin because of its vasopressin content, pure oxytocin appears to have relatively less potency (RMK++=0.86). Rats used for the above study were not treated with an estrogen, nor were they examined to determine whether or not they were cycling. Some were probably very immature and anestrous, but others were cycling, as judged by the occasional appearance of typical estrous uteri. Practical use was made of the apparently unique RMg++ of oxytocin by comparing it to the RjigH of natural peptides which resembled oxytocin in their chromatographic and pharmacological characteristics. Munsick et al. (2) thus tentatively identified oxytocin in eluates of paper chromatograms of extracts of chicken posterior pituitary glands. They based this identification partially upon an Rjtfg++ of less than 1.0 for the distal, oxytocin-like principle in paper chromatograms. Presence of oxytocin in the chicken posterior lobe was later proved chemically by Acher et al. (3). Recently, Chan et al. (4) stated that
High precision SIMS measurements of dopant concentration in III–V semiconductors

Abstract Secondary ion mass spectrometry (SIMS) has been used to precisely mesure dopant concentration in epitaxial GaAs and Al x Ag 1− x As films. Calibration was performed by ion implantation which introduced a known quantity of dopant into the films and thus established an internal standard in each specimen measured. The precision of the method is dependent upon the accuracy of the implant dose (5%), the signal-to-noise level in the SIMS measurement, and the accuracy of the SIMS crater depth measurement (5%). The typical worst case measurement errors for the procedure can be reduced to twenty per cent. This technique has been used to measure Zn implanted GaAs and the incorporation of Si donor in Al x Ga 1 − x As films where x is varied from 0.2 to 0.4.
Discriminatory von Neumann-Morgenstern solutions

Abstract A discriminatory von Neumann-Morgenstern (vN-M) solution assigns fixed payoffs to certain players and permits the remaining players to arbitrarily redistribute their payoffs. This paper gives a complete characterization of discriminatory vN-M solutions, describing the role of the players and their payoffs in terms of minimal vital coalitions and Cores of reduced games resembling the DavisMaschler reduced game. The characterization makes it computationally easy to verify proposed discriminatory vN-M solutions, and may be used to determine all discriminatory vN-M solutions.
Inducible Cre recombinase activity in mouse cerebellar granule cell precursors and inner ear hair cells

A transgenic mouse line expressing the CreER(TM) fusion protein under the control of the Math1 enhancer was generated. Expression of the transgene in the postnatal mouse was restricted to hair cells of the inner ear and granule neurons in the external granule layer of the cerebellum in a temporally regulated manner. Cre activity was virtually nonexistent in uninduced mice; however, treatment of newborn pups with tamoxifen, leading to nuclear translocation of the fusion protein, resulted in efficient recombination at LoxP sites in the appropriate cell types. Up to two thirds of cerebellar granule neurons and 80-90% of cochlear hair cells underwent Cre-specific recombination. This mouse line provides a powerful tool to dissect gene function at early and late stages in development of the cerebellum and inner ear.
Differential Regulation of the Cardiac Sodium Calcium Exchanger Promoter in Adult and Neonatal Cardiomyocytes by Nkx2.5 and Serum Response Factor

Abstract J. G. Muller, J. T. Thompson, A. M. Edmonson, M. S. Rackley, H. Kasahara, S. Izumo, T. C. Mcquinn, D. R. Menick and T. X. O'Brien. Differential Regulation of the Cardiac Sodium Calcium Exchanger Promoter in Adult and Neonatal Cardiomyocytes by Nkx2.5 and Serum Response Factor. Journal of Molecular and Cellular Cardiology (2002) 34 , 807–821. Nkx2.5 and serum response factor (SRF) are critically important transcription factors in cardiac morphogenesis. They are also widely expressed in adult cardiomyocytes, but there is little data to indicate their possible role in adult cardiac cells. In this paper we demonstrate that the interaction of Nkx2.5 and SRF in cardiac-specific gene regulation is different between neonatal and adult cardiomyocytes. Our experimental model utilizes transient transfection and adenovirus mediated gene transfer of the proximal promoter fragment of the cardiac isoform of the sodium-calcium exchanger gene (NCX1). This promoter construct (NCX184) contains a single Nkx2.5-response element (NKE) and a single serum response element (CArG). In rat neonatal cardiomyocytes NCX184 activity is substantially induced with Nkx2.5 or SRF and additively with both. Mutagenesis of these NKE and CArG elements demonstrated the specificity of the interactions, which was confirmed with gel retardation analysis of cardiac ventricular tissue. In contrast, in adult cardiomyocytes, co-infection of Nkx2.5 and SRF adenovirus vectors showed Nkx2.5 induction but SRF did not have additive effects on NCX1 promoter regulation. As opposed to NCX1, the proximal atrial natriuretic factor (ANF) promoter was regulated identically in response to SRF and Nkx2.5 in both adult and neonatal cardiomyocytes. These results show that Nkx2.5–SRF interactions are capable of producing different transcriptional responses in adult versus neonatal cardiomyocytes, implying important differences in NCX1 promoter tertiary complex formation dependent on developmental stage.
Intercomparison of Interannual Variability of the Global 200-hPa Circulation for AMIP Simulations

Abstract The 200-hPa divergence and streamfunction from the 30 models of the Atmospheric Model Intercomparison Project (AMIP) are compared. The data used are in the form of monthly averages and are filtered to a spatial resolution of T10, although the actual spatial resolution of the models varies from R15 to T42. The tools of the analysis are principal components analysis (PCA) and common principal components (CPC). These analyses are carried out on the 120 months of data with the climatological annual cycle removed and in the case of the streamfunction with the zonal average also removed. The AMIP period (1979–88) encompasses two El Nino–Southern Oscillation (ENSO) events (1982–83 and 1986–87), and as could be expected the ENSO characteristic response has a prominent impact in the model simulations. The results indicate the following. The PCA of the divergence has a dominant mode that is similar for all the models and has the signature of an ENSO response. It has an east–west dipole of divergence anomal...
Being gay and doing research on homosexuality in non‐western cultures

(1993). Being gay and doing research on homosexuality in non‐western cultures. The Journal of Sex Research: Vol. 30, No. 2, pp. 115-120.
An optical interferometer in earth orbit for testing general relativity

Abstract We discuss an optical interferometer that might be built for placement in Earth orbit to measure the second-order gravitational bending of starlight by the sun. Other uses of such an instrument are also mentioned.
A pseudo-empirical log-likelihood estimator using scrambled responses

In this paper, we propose an empirical log-likelihood estimator for estimating the population mean of a sensitive variable in the presence of an auxiliary variable. A new concept of conditional mean squared error of the empirical likelihood estimator is introduced. The proposed method is valid for simple random and without replacement sampling (SRSWOR) and could easily be extended for complex survey designs. The relative efficiency of the proposed pseudo-empirical log-likelihood estimator with respect to the usual, and to a recent estimator due to Diana and Perri (2009b), has been investigated through a simulation study.
Can Online Mediation Be Transformative? Tales from the Front

This article briefly reviews the precepts of the transformative model of mediation, examines the types of disputes that are most suited to online mediation, and offers some examples from online commercial mediation to show how some of the ideas and techniques borrowed from the “transformative model” may be applied in the realm of online mediation.
Oral clefts, maternal smoking, and TGFA: a meta-analysis of gene-environment interaction.

Abstract Objective: A meta-analysis was performed to examine the association among maternal cigarette smoking, infant genotype at the Taq1 site in the transforming growth factor α (TGFA) locus, and risk of nonsyndromic oral clefts, both cleft palate (CP) and cleft lip with or without cleft palate (CL/P). Design: Five published case-control studies were included in the meta-analyis. Pooled Mantel-Haenszel odds ratios (OR) and 95% confidence intervals (CIs) were computed. Gene-environment interaction was also assessed by using the pooled data in a case-only analysis and polytomous logistic regression. Results: Among nonsmoking mothers, there was no evidence of any increased risk for CP if the infant carried the TGFA Taq1 C2 allele. If the mother reported smoking, however, there was an overall increased risk for CP if the infant carried the C2 allele (ORsmokers = 1.95; 95% CI = 1.22 to 3.10). TGFA genotype did not increase risk to CL/P, regardless of maternal smoking status. Polytomous logistic regression re...
Oxygen in a box: an oxygen atom surrounded by a cube of 8 lithium atoms

Abstract Although molecular structures in which there is an oxygen atom surrounded by a tetrahedral or an octahedral array of cations are familiar (though not common), no molecule has previously been reported in which an oxygen atom is surrounded by a cubic array of metal atoms. We describe here such a molecule, (C11H13N3)6Li8O, where C11H13N3 is a bidentate, uninegative ligand.
Retention of incompletely learned CER in rats

Two groups of rats acquired an incompletely learned conditioned emotional response. One of the groups was tested 1 day, the other 90 days following acquisition. There was no difference in the degree of suppression exhibited by the two groups.
Magnitude and consequences of missing the acute infarct-related circumflex artery

Emergent reperfusion strategies are integral to providing optimal patient outcomes in the setting of acute coronary artery occlusion. ST-segment elevation on the surface 12-lead electrocardiogram, although specific as a surrogate marker, is insensitive to acute posterior circulation coronary artery occlusion. Studies of non-ST-segment elevation acute coronary syndrome consistently identify patients who have epicardial vessel occlusion at the time of initial angiography, which is usually delayed for hours or days after the initial presentation. In addition, studies of ST-segment elevation myocardial infarction often divulge a disparity in identification of the infarct-related artery, with an underrepresentation of the left circumflex artery. Taken together, it is likely that many patients with left circumflex artery occlusion are "missed" during the early phases of myocardial infarction due to the electrocardiographically silent nature of the posterior territory, resulting in delayed myocardial salvage and worse cardiovascular outcomes. In this review, we report on the magnitude of missed left circumflex infarction and the consequences of this delay in diagnosis. We review the electrocardiographic findings of left circumflex occlusion and discuss strategies to enhance early identification. Heightened awareness of this clinical scenario and the available methods to avoid missing this elusive diagnosis are imperative in our quest to further improve the outcomes of patients with acute myocardial infarction.
REpeating Pattern Extraction Technique (REPET): A Simple Method for Music/Voice Separation

Repetition is a core principle in music. Many musical pieces are characterized by an underlying repeating structure over which varying elements are superimposed. This is especially true for pop songs where a singer often overlays varying vocals on a repeating accompaniment. On this basis, we present the REpeating Pattern Extraction Technique (REPET), a novel and simple approach for separating the repeating “background” from the non-repeating “foreground” in a mixture. The basic idea is to identify the periodically repeating segments in the audio, compare them to a repeating segment model derived from them, and extract the repeating patterns via time-frequency masking. Experiments on data sets of 1,000 song clips and 14 full-track real-world songs showed that this method can be successfully applied for music/voice separation, competing with two recent state-of-the-art approaches. Further experiments showed that REPET can also be used as a preprocessor to pitch detection algorithms to improve melody extraction.
Adsorption of cations onto positively charged surface mesopores.

Abstract Uwe Neue developed a theoretical treatment to account for the adsorption of ions on mesopores of packing materials the walls of which are bonded to ionic ligands but left this work unfinished. We elaborated upon this treatment and refined it, based on the equivalence that he suggested between charged surface particles and a membrane that separates two ionic solutions but is impermeable to one specification. He had written that the electro-chemical potentials in both ionic solutions are equal (Donnan equilibrium). The equilibrium between the surface and the pore concentrations is accounted for by an homogeneous electrostatically modified Langmuir (EML) isotherm model. The theoretical results are presented for four different charge surface concentrations σ0 = 0, 0.001, 0.002, and 0.003 C/m2, using a phosphate buffer ( W S pH = 2.65 ) of ionic strength I = 10 mM. The average pore size, the specific surface area, and the specific pore volume of the stationary phase were Dp = 140 A, Sp = 182 m2/g, and Vp = 0.70 cm3/g, respectively. The theoretical results provide the quantitative difference between the ionic strength, the pH, and the concentrations of all the ions in the pores and in the bulk eluent. The theory predicts (1) that the retention times of cations under linear conditions is lower and (2) that their band widths under overloaded conditions for a given retention factor shrinks when the surface charge density σ0 is increased. These theoretical results are in good agreement with experimental results published previously and explain them.
Linear systems with non-stationary random inputs†

This paper concerns the response correlation matrix of a linear time variable system with stationary or non-stationary stochastic inputs modulated by linear homogeneous operators. By adapting Lanczos' ‘selected points’ method an algorithm is introduced to compute the state covariance matrix of systems with deterministic initial state. Certain computational features of response correlation matrices of systems with random initial state and random inputs are also outlined. Limited numerical studies indicate that the proposed method is efficient to treat uni-dimensional and small-order multi-dimensional systems. Mean square response comparisons with some of the previously studied systems indicate good agreement and the saving in machine time appears to be substantial.
Stabilization of Metal Nanoparticles in Cubic Mesostructured Silica and Its Application in Regenerable Deep Desulfurization of Warm Syngas

Metal and metal oxide nanoparticles supported on high surface area materials are widely used in industry for fuel and chemical production and for environmental pollution control, but preventing nanosized particle sintering has remained a great challenge. In this paper, we report that Ni−Cu alloy nanoparticles can be effectively stabilized in cubic mesostructured silica (SBA-16) following a conventional impregnation and thermal treatment process. The three-dimensional interconnected cage structure of the mesoporous SBA-16 allows good accessibility of reactant gas molecules to the metal nanoparticles and confines these particles within its nanosized cages. This confinement hinders metal nanoparticle migration and sintering under harsh conditions. A new class of regenerable metal-based adsorbents which can remove sulfur impurities from warm syngas stream down to less than 60 parts per billion by volume (ppbv) is described. This same confinement strategy is expected to have impact for minimizing sintering or ...
Understanding immigration in a national systems of innovation framework

This paper argues that the systems of innovation analytic framework affords valuable insights into the impact of highly-skilled immigrants on innovation processes in developed countries. The paper first reviews why highly-skilled migration has risen on the agenda of policy-makers and researchers and sets forth my interpretation of the systems of innovation framework. It then builds on this interpretation by arguing that the interaction between immigrants and the organizations and institutions into which they are inserted by a national system can (under some circumstances) affect the system's capacity for innovation by changing transaction costs and the management of uncertainty. Although it tackles just one aspect of the complex puzzle presented by global flows of skilled people, the paper prepares the conceptual ground for a broader assault on this important issue. Copyright , Beech Tree Publishing.
On the Maximum Likelihood Estimate of Cell Probabilities.

Abstract : The paper contains a study of the law of the iterated logarithm for differences between empirical frequencies and true cell probabilities when there are a countable number of cells. It is shown that upper and lower classes for the normalized maximum of the absolute differences are precisely those for (the normalized absolute differences for) a cell whose probability is closest to 1/2. (Author)
The distribution and morphologic variation of hyaline deposits in odontogenic lesions

The deposits of homogeneous hyaline substances present in epithelium-containing odontogenic lesions were evaluated in 201 tumors. The material was evaluated to establish the types of odontogenic lesions capable of producing the substance, its frequency of occurrence, its microscopic variation, and the different morphologic relationships of the substance to the odontogenic epithelium present in the lesions. The deposits were found in 40.3 percent of the 201 odontogenic tumors and frequently in several other nonneoplastic odontogenic lesions. It was most consistent in odontomas but was found to some extent in all types of epithelium-containing odontogenic tumors. It was present either in a basement membrane location or as a diffuse deposit in the connective tissue. In the latter location, the deposits commonly contained enclaved islands of odontogenic epithelium and had a distinct tendency to calcify. The study also suggests that since some odontogenic tumors may contain large amounts of the hyaline deposits, multiple sections through different parts of the tumor may be required to find the epithelial elements necessary for the correct diagnosis.
Cloning and embryonic expression patterns of the chicken CELF family.

The CUG-BP and ETR-3-like factor (CELF) protein family has been implicated in the regulation of premRNA alternative splicing, mRNA stability, and translation. Here we discuss the evolution and radiation of the CELF protein subfamilies, and report the cloning of the chicken CELF family members. In this study, we examined the embryonic expression patterns of the CELF family in the chick by in situ hybridization. We found that the tissue specificity reported for CELF proteins in the adult is established early during embryogenesis. Members of one subfamily, CUG-BP1 and ETR-3, are broadly expressed in the early embryo, while members of the second subfamily, CELF4-6, are restricted primarily to the nervous system. Expression patterns of individual CELF genes in several tissues, including the heart, liver, eye, and neural tube, exhibit distinct, yet overlapping, expression patterns. This suggests that different members of the CELF family play distinct functional roles during embryogenesis. Developmental Dynamics 236:2216 –2224, 2007. © 2007 Wiley-Liss, Inc.
Analysis of hydroxyapatite surface coverage by amelogenin nanospheres following the Langmuir model for protein adsorption.

The assembly of amelogenin protein into nanospheres is postulated to be a key factor in the sta- bility of enamel extracellular matrix framework, which provides the scaffolding for the initial enamel apatite crystals to nucleate and grow. Adsorption isotherms were evaluated in order to investigate the nature of in- teractions of amelogenin nanospheres with hydroxyap- aite crystals in solution, where their assembly status and particle size distribution are defined. We report that the adsorption isotherm of a recombinant mouse amelo- genin (rM179) on synthetic hydroxyapatite crystals can be described using a Langmuir model indicating that amelogenin nanospheres adsorb onto the surface of apatite crystals as binding units with defined adsorption sites. The adsorption affinity and the maximum ad- sorption sites were 19.7 · 10 5 L/mol and 6.09 · 10 )7 mol/m 2 , respectively, with an r 2 value of 0.99. Knowing the composition and particle size distribution of ame- logenin nanospheres under the condition of adsorption experiments, we have calculated the number of nano- spheres and the crystal surface area covered by each population of nanospheres at their maximum adsorp- tion. It was found that total maximum binding covers 64% of the area unit. This observation supports the speculation that amelogenin binding onto apatite sur- face is selective and occurs only at certain sites.
Minimal and maximal product differentiation in Hotelling's duopoly

Abstract Hotelling's (1929) model of duopolistic competition is re-examined. A family of utility functions is used which has as a special case Hotelling's original utility function. In a two-stage location-price game it is shown that an equilibrium exists when the curvature of the utility functions in the space of characteristics is sufficiently high. The (subgame-perfect) equilibrium never exhibits minimum product differentiation. On the other hand, not all equilibria are at maximal product differentiation.
Low-power implementation of a 4×4 two-dimensional discrete Pascal Transform

The discrete Pascal Transform (DPT) has been shown to be very useful in signal and image processing applications in the detection of edges and bumps. In this paper, an efficient low-power VLSI implementation for a 4×4 two-dimensional discrete Pascal transform is presented. The proposed approach uses multiple supply voltage sources and sleep transistors to produce a balance between power savings and performance. The circuit is synthesized with a TSMC 0.18um technology using both standard and custom designed cells. Our proposed approach provides a power savings of 22 % compared to the single supply voltage case.
Assessment of pain during head and neck irradiation

Radiation therapy for patients with head and neck malignancies frequently results in painful mucositis, which is usually poorly controlled with standard analgesics or topical anesthetics. To better understand the temporal development of radiation-induced pain and the effects of this pain on activities of daily living, 14 patients undergoing radiation therapy for a newly diagnosed head and neck malignancy completed daily pain diaries during the course of irradiation. All patients developed painful mucositis, usually beginning during the second or third week of radiation. Despite the use of analgesics/anesthetics, pain was rated as moderate or severe on 37% of treatment days and was noted to be constant or present throughout most of the day on 58% of treatment days. Eating and sleep disturbances related to pain occurred on 55% and 34% of treatment days, respectively. Eight patients had greater than a 2-kg weight loss. Radiation induces a predictable pattern of pain and comorbidity, which may be amenable to earlier and more aggressive analgesic treatment.
IT governance and business value in the public sector organizations - The role of elected representatives in IT governance and its impact on IT value in U.S. state governments

This paper studies IT business value in the public sector organizations, to which the information systems (IS) literature so far has paid little attention. Specifically, we investigate the moderating effect of IT governance on the relationship between IT investments and government performance. Drawing upon the theory of political control on bureaucracy from the political sciences literature, we hypothesize that the presence of legislative controls on IT management increases returns to IT spending, which are measured by cost efficiency. Our empirical analysis in the context of U.S. state governments shows that formal establishment of a chief information officer (CIO) position by legislation is a key prerequisite to positive returns from IT expenditures in state governments. Also, the impact of IT spending on state cost efficiency increases when a state senate approves appointment of CIO nomination than when it does not. This study contributes to the IS literature by demonstrating the importance of elected representatives as part of IT governance in the public sector organizations.
Stochastic dynamic prediction

Stochastic dynamic prediction assumes the laws governing atmospheric behavior are entirely deterministic, but seeks solutions corresponding to probabilistic statements of the initial conditions, thus recognizing the impossibility of exact or sufficiently dense observations. The equation that must be solved is the continuity equation for probability. For practical reasons only approximate solutions to this equation are possible in general. Deterministic forecasts represent a very low order of approximation. More exact methods are developed and some of the attributes and advantages of stochastic dynamic predictions are illustrated by applying them to a low order set of dynamic equations. Stochastic dynamic predictions have significantly smaller mean square errors than deterministic procedures, and also give specific information on the nature and extent of the uncertainty of the forecast. Also the range of time over which useful forecasts can be obtained is extended. However, they also require considerably more extensive calculations. The question of analysis to obtain the initial stochastic statement of the atmospheric state is considered and one finds here too a promise of significant advantages over present deterministic methods. It is shown how the stochastic method can be used to assess the value of new or improved data by considering their influence on the decrease in the uncertainty of the forecast. Comparisons among physical-numerical models are also made more effectively by applying stochastic methods. Finally the implications of stochastic dynamic prediction on the question of predictability are briefly considered, with the conclusion that some earlier estimates have been too pessimistic. DOI: 10.1111/j.2153-3490.1969.tb00483.x
A general theory of interpersonal exchange

A general theory of interpersonal exchange is developed from a public goods, public choice point of view and within an analytical context that assesses both the benefits and the costs of social interaction. Social transaction benefits and costs are specified as a composite function of interpersonal bindingness, which itself depends upon five parameters. The model provides for the determination of an optimal personal degree of bindingness in a two-person relationship. Extensions encompass the more interesting reaction case, where two individuals each select their own optimal personal bindingness levels. Applications and conclusions complete the paper. qu]When love beckons to you, follow him, Though his ways are hard and steep ... For even as love crowns you so shall he crucify you. Even as he is for your growth so is he for your pruning. Kahlil Gibran The Prophet
Prezygotic barriers to gene flow between Taraxacum ceratophorum and the invasive Taraxacum officinale (Asteraceae)

Prezygotic reproductive barriers limit interspecific gene flow between congeners. Here, I examine the strength of floral isolation and interspecific pollen-pistil barriers between an invasive apomictic, Taraxacum officinale, and the indigenous sexual alpine dandelion, Taraxacum ceratophorum. Experimental arrays of either native inflorescences or a mixture of native and exotic inflorescences were used to examine insect preference and to track movement of a pollen analog. Using hand-pollinations, conspecific and heterospecific pollen germination success on native stigmas was compared. To additionally test for interspecific pollen competition, T. ceratophorum plants received one of three possible hand-pollinations: control conspecific pollination, concomitant conspecific and heterospecific pollination (mixed), or conspecific pollen followed by heterospecific pollen 15 min later (staggered). Floral isolation was negligible as no insect preference was detected. On a presence/absence basis, florets on native inflorescences received slightly less pollen analog from heterospecific donors than from conspecific donors; however, the amount of dye particles transferred from either Taraxacum species to stigmas on recipient T. ceratophorum inflorescences was equivalent. In contrast to weak floral isolation, strong pollen germination and pollen competition barriers should reduce the potential for hybridization. Heterospecific T. officinale pollen exhibited reduced germination success on T. ceratophorum stigmas in comparison to conspecific pollen. Furthermore, a significant pollen-competition effect on the percentage of hybrid offspring was detected only when T. officinale preceded T. ceratophorum pollen by 15 min. This result indicates that conspecific pollen out-competes heterospecific pollen but further suggests that biotic and abiotic factors reducing pollen accrual rates may partially remove barriers to natural hybridization.
Radiation exposure as a consequence of spinal immobilization and extrication.

Abstract Background Extrication and spinal immobilization in the trauma patient with unknown injuries is a common practice of emergency medical services. High-speed crashes occurring in open-wheel racing seldom result in extrication or spinal immobilization. Objectives To evaluate the safety of self-extrication in IndyCar® (Indianapolis, IN) by comparing drivers self extricated with full spinal immobilization and subsequent radiation exposure. Methods A retrospective review of prospectively collected de-identified IndyCar® crash and drivers’ medical records was performed at treating Level I trauma centers. One hundred thirty-five crash incidents involving drivers evaluated by a medical team were included. Any driver with severe multiple trauma was excluded due to distracting injuries. Drivers underwent standard protocol for postcrash injury. Diagnostic and treatment outcomes including spinal and neurologic injury, need for surgery, and radiation exposure were collected for review. Results Self-extrication occurred in 121 (90%) crashes, and overall cumulative radiation exposure ranged from 100 to 250 mSv, or 0.82–2.06 mSv per driver. Extrication with full spinal immobilization occurred in 14 (10%) drivers, with overall cumulative radiation exposure ranging from 140 to 350 mSv, or 10–25 mSv per driver. A total of 29 injuries were identified, nine of which (31%) were spinal. In these, six were emergency medical services extricated and three self extricated. None were unstable spinal fractures resulting in surgical care, surgical disease, or neurologic deficit. Conclusion In our IndyCar® racing experience, a protocol-led self-extrication system resulted in neither a mismanagement of an unstable spinal fracture nor neurological deficit, and reduced radiation exposure.
Endoscopic management of common bile duct stones

Endoscopic sphincterotomy has become the undisputed method of choice for removing common bile duct calculi following previous cholecystectomy. This approach has also been applied to selected patients with intact gallbladders deemed unfit for surgery. More recently, endoscopic clearance of the bile duct has been used in concert with laparoscopic cholecystectomy to avoid laparotomy. Modalities available for stone therapy via the endoscope include baskets and balloons, mechanical lithotripters, electrohydraulic lithotripsy probes, and laser energy. In difficult cases stents may be placed to provide drainage in lieu of stone extraction.
Heparin dosing in patients undergoing coronary intervention

Unfractionated heparin remains an essential component of the antithrombotic regimen in patients undergoing coronary intervention, although the timing, dosing, and duration of heparin therapy have evolved over the past several years. Complications associated with heparin use include bleeding events, which occur in 3.9-16.4% of patients receiving conventional heparin. Less commonly, clinically significant thrombocytopenia develops, related to the duration of heparin administration. In patients undergoing coronary intervention who do not receive platelet glycoprotein (GP) IIb/IIIa inhibitors, sufficient heparin should be given to achieve an activated clotting time (ACT) of 250-300 seconds with the HemoTec device and 300-350 seconds with the Hemochron device. There is a general trend to use lower, weight-adjusted heparin dosing (70-100 units/kg) to avoid excessive levels of anticoagulation, with additional heparin boluses to achieve a therapeutic ACT level. When GP IIb/IIIa inhibitors are used, weight-adjusted heparin dosing can be decreased to 70 units/kg to achieve a target ACT of 200 seconds with either the HemoTec or Hemochron device. After uncomplicated coronary intervention, there appears to be little value associated with continued heparin therapy, and the risk of bleeding complications clearly increases with longer durations and higher levels of anticoagulation after coronary intervention.
Validity of a continuous metabolic risk score as an index for modeling metabolic syndrome in adolescents.

Purpose Although continuous values of metabolic syndrome risk scores (cMetS) has been suggested for modeling the association between potential risk factors and metabolic syndrome (MetS) in young people, the construct validity of cMetS has not been sufficiently examined in a representative sample of youngsters. This study examined: (i) sex and race/ethnic-specific optimal cut-off points of cMetS that are associated with MetS and (ii) the construct validity of cMetS in 12- to 19-year old non-Hispanic white (NHW), non-Hispanic black (NHB), and Mexican-American (MA) subjects. Methods Data (n = 1239) from the 2003 to 2004 and 2005 to 2006 National Health and Nutrition Examination Surveys were used in this study. cMetS was derived by aggregating age- and sex-standardized residuals of arterial blood pressure, triglycerides, glucose, waist circumference, and high-density lipoprotein cholesterol. Receiver operating characteristics analysis was used to determine the validity and performance of cMetS. The overall performance of the receiver operating characteristics test was quantified with area under the curve (AUC). Results A graded relationship between cMetS and increased number of MetS factors was observed, with MetS factors of 3 or greater yielding the greatest cMetS. In male adolescents, the optimal cMetS cut-off points of cMetS that are associated with MetS in NHW, NHB, and MA were 2.01, 2.45, and 2.34, respectively. The corresponding values in female adolescents for NBW, NHB, and MA were 1.93, 2.12, and 2.23, respectively. The construct validity of cMetS for MetS was high (AUC ≥0.885; sensitivity ≥66.7; specificity ≥74.8%). Conclusions cMetS appears to be a suitable index for investigating the association between potential risk factors and MetS in adolescents. An understanding of the role of genetic and environmental risk factors in MetS in children may be enhanced with the use of cMetS.
On Age Spreads in Star-forming Regions

I consider current observational constraints on age spreads in star-forming regions and recent attempts to infer the star-forming histories of molecular cloud complexes. My analysis concentrates on low-mass pre–main-sequence stars on Hayashi tracks, which constitute the bulk of the stellar population. Current observational and theoretical uncertainties probably preclude any robust inferences of the detailed variation of star formation rates as a function of time. These results do not change the conclusion, supported again recently by the systematic study of Palla & Stahler, that star formation is rapid.
Cytogenetics of human malignant melanoma.

There has been a tremendous recent resurgence of interest in examining chromosomal abnormalities in human cancers (particularly solid tumors). This interest has been stimulated by the molecular examination of recurring chromosome abnormalities, and the recognition that they may pinpoint the location of growth regulatory sequences (e.g. cellular oncogenes). This finding coupled with the clear recognition that specific chromosome abnormalities can also have important diagnostic and prognostic implications, have caused this avenue of research to expand at a significant rate. The following brief review will summarize the current state of knowledge regarding recurring chromosome abnormalities in human malignant melanoma. A discussion of chromosome changes in pre-malignant skin lesions, primary melanoma, and metastatic melanoma is described. Brief descriptions of the potential clinical utility, and biologic relevance of chromosome abnormalities in this disorder are also discussed.
A modification of the Finnis-Sinclair potentials for highly deformed and defective transition metals

Abstract A modification is introduced to the original Finnis-Sinclair potentials for transition metals which substantially improves their pressure versus volume behaviour and overcomes their high-compression instability. With this modification good results are obtained for the energetics instability. With this modification good results are obtained for the energetics and the stable configuration of vacancies and interstitials. Excellent agreement is also found between the lattice parameter dependence of the cohesive energy of Mo as obtained using the modified potentials and via self-consistent augmented-spherical-wave calculations. With the proposed modification, the repulsive component of the modified potentials turns out to be akin to a Wedepohl potential.
An unusual case of hereditary fibrous osteodysplasia (fragilitas ossium) with replacement of dentine by osteocementum

Abstract Unique dental pathology has been reported in a case of hereditary fibrous osteodystrophy, which was thought consistent with some stage of fragilitas ossium. Ten teeth were studied all of which showed extensive resorptive processes affecting primarily the dentine, but also involving the cementum. This resorption which in some instances removed almost the entire root of the tooth, was repaired by trabeculated osteocementum causing a complete change in the histologic appearance of the tooth. Two interesting conclusions can be drawn from the histologic study of these teeth. The first is that teeth may resorb in a similar way as bone, and therefore the fact that they are not involved in hyperparathyroidism is not because they are immune to resorption. The second conclusion concerns the genesis of osteoclasts. The fact that osteoclasts appear in dentine which contains no enclaved cells should disprove the theory that they are a conglomeration of liberated bone corpuscles.
PCB movement, dechlorination, and detoxication in the acushnet estuary

Congener-specific analyses of the PCBs in Acushnet Estuary (New Bedford, MA) sediments and waters were undertaken to identify the PCB alteration and transport processes occurring in coastal marine sediments. These analyses indicated that (a) the PCBs deposited at the sediment sites sampled had originally consisted of Aroclors 1242 and 1254, in widely varying proportions; (b) these PCBs had undergone vertical movement within the sediments, rather than remaining stratified, but not horizontal translocation between sites; (c) they had also undergone extraction into the water, albeit at declining rates, with some consequent changes in composition but (d) the major compositional change was caused by a previously unreported type of reductive dechlorination process, designated Process H. This presumably anaerobic microbial process, subsequently identified at several other locations as well, had selectively removed non-ortho chlorines from most of the higher PCB congeners, especially those associated with acute toxic effects. It appeared to have begun near the upper end of the estuary and not yet reached its lower portions, thus providing a marker for tracing the origin of the PCBs in estuarine water samples.
Switching channels: The effects of television channels on the mental representations of television news

This study tests how people differentiate between television channels, conceptualized as having two important properties: channels differ in degree of specialized content and are positioned within arrays varying in size. Participants watched news stories identified as emanating from either specialist news channels or from generalist channels. News on specialist channels was rated higher on news attributes and evaluated more positively than identical news on generalist channels. News watched on one channel was rated as more similar than identical news watched on four channels. Participants who watched news on four channels rated the television picture quality higher than those who watched on one channel. This pattern of results is consistent with the notion of channel as a place where television programs—and the people and action in them—exist.
Evidence for Probable Sexual Transmission of the Hepatitis G Virus

A cross-sectional epidemiology study evaluated the role of sexual activity and sexually transmitted diseases (STDs) in the transmission of hepatitis G virus (HGV/GBV-C) and other hepatitis virus infections in 944 subjects. There was a statistically significant higher prevalence of HGV/GBV-C, hepatitis B virus, and hepatitis C virus exposure in the STD clinic group (i.e., subjects who were currently seeking treatment for an STD) compared with the group who never had received treatment for an STD. In a comparison of the subjects with an STD versus those without an STD, the prevalence of HGV/GBV-C was 11.3% versus 4.9%, on the basis of polymerase chain reaction (PCR) results alone, and 36.6% versus 8.8%, when results of PCR and enzymelinked immunosorbent assay were combined. Sexual activity and, possibly, the presence of an STD increases the risk of HGB/GBV-C transmission.
A Study of the Dose-Effect Relationship of Cholestyramine in Children with Familial Hypercholesterolemia

Premature atherosclerosis is a major public health problem in the United States. Points at issue for the pediatrician are, for example: what is the appropriate age to identify various risk factors associated with early cardiovascular disease; what preventive measure should be implemented, and what really is the role of the pediatrician in such a task? Although it is not proven that reduction in plasma cholesterol will lower the incidence of coronary artery disease, most pediatricians agree that children that have inherited high cholesterol levels represent a group of sufficiently high risk to warrant identification and treatment.
On the calculation of the free energy change accompanying the growth of escherichia coli K-12 on succinic acid.

Determinations of the ΔG0′ accompanying the growth of Escherichia coli K-12 on succinic acid are made using 2 different methods. The ΔG0′ accompanying catabolism could be calculated directly because the thermodynamic properties of the reactants and products are known. The ΔG′accompanying anabolism could not be calculated directly because the ΔGf value for a unit mass of cells was not known. A description is given of a deduction that the ΔG′ accompanying anabolism is zero, or nearly so. This is followed by a description of 2 methods, whereby the free energy of formation of a unit quantity of cellular substance can be calculated. The 2 values obtained by these methods are used to calculate the free-energy change accompanying anabolism, the resultant values being 1.72 and -11.68 kJ, respectively, with an average of −4.98 kJ (−1.19 kcal). This value is sufficiently close to zero that it can be considered to be so, indicating that the ΔG′ accompanying metabolism is that of catabolism alone.
Determination of Abacavir in maternal plasma, amniotic fluid, fetal and placental tissues by a polarity switching liquid chromatography/tandem mass spectrometry method

A rapid and efficient high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) method for the determination of concentrations of the carbocyclic nucleoside antiviral Abacavir in maternal rat plasma, amniotic fluid, placental and fetal tissue samples has been developed and validated. All tissue samples were homogenized in water prior to analysis and all samples were prepared by acetonitrile precipitation followed by dilution with HPLC-grade water. Separation of the analyte and internal standard from the matrices was achieved on a C8 analytical column (2.1 × 150 mm, 5 μm particle size). The mobile phase consisted of 10 mM ammonium acetate/acetonitrile using a gradient method at a flow rate of 0.25 mL/min for all matrices. The method yields retention times of approximately 3.4 and 5.1 min for the internal standard (Azidouridine) and Abacavir, respectively. For all matrices the limit of detection was approximately 1 ng/ml. Recoveries from the different matrices ranged from 53–87% for Abacavir and from 69–84% for Azidouridine. Within- and between-run precision (%RSD) and accuracy (%Error) were under 15% for all matrices. Copyright © 2004 John Wiley & Sons, Ltd.