cssi/SciSciGPT-SciSciNet huggingface dataset:
Differential signal transduction of alternatively spliced FGFR2 variants expressed in human mammary epithelial cells

Gene amplification and protein overexpression of fibroblast growth factor receptor 2 (FGFR2) characterize the SUM-52 breast cancer cell line developed in our laboratory. SUM-52 cells express nine distinct alternatively spliced isoforms of FGFR2. Among these isoforms are two otherwise identical FGFR2 variants that express either the C1 or C3 carboxyl terminus. FGFR2-C3 variants are not normally expressed by human mammary epithelial (HME) cells, and we have shown that overexpression of FGFR2-C3 in HME cells results in potent transformation. In particular, FGFR2-C3 expression leads to robust levels of constitutively tyrosine phosphorylated FRS2 in the absence of ligand stimulation. In contrast, overexpressed FGFR2-C1 requires constant stimulation with exogenous keratinocyte growth factor (KGF) to mimic the signaling capability of FGFR2-C3. However, activation of FRS2 that results from KGF-stimulated FGFR2-C1 signaling is transient and is associated with a mobility shift of FRS2 not observed when this signaling molecule is activated by the C3 isoform of FGFR2. Mutation of the only tyrosine phosphorylated site present in the C1 terminus and absent from C3, Tyr769, did not yield a receptor that rivaled the potent signaling of FGFR2-C3. We therefore conclude that aberrant expression of alternatively spliced isoforms of FGFR2 with the C3 carboxyl terminus in the SUM-52 breast cancer cells results in sustained activation of signal transduction leading to transformation.
Extinction spectroscopy: A novel laser spectroscopic technique

Abstract This letter describes the first demonstration of a novel laser spectroscopic technique for making high resolution measurements on core-excited levels and transitions. Specifically it allows the accurate measurement of level positions, oscillator strengths, and autoionizing linewidths not easily observed by other methods. This technique is called extinction spectroscopy and is here demonstrated by measurement of the lifetime and position of the Li 1s(2s2p 3 P) 2 P core excited level.
Dicyanogen trapped in a solid matrix at room temperature: x-ray structure of trans-[Ni(CN)2(PPh3)2]·(C2N2)

Cristallisation dans le groupe P1 et affinement de la structure jusqu'a R=3,9%. Le reseau moleculaire forme par la repetition de complexes trans-[Ni(CN) 2 (PPh 3 ) 2 ] contient des canaux de taille importante
Factors related to doctoral dissertation topic selection

Although the completed doctoral dissertation represents the culmination of a doctoral program, is often published in journal articles, and serves as the foundation of the early research career of the author, the dissertation has received relatively little attention as a subject of research in its own right. To learn more about how students select their dissertation topics, all doctoral graduates of a major midwestern research university over the one year period from spring quarter, 1986, through winter quarter, 1987, were surveyed. Results indicate that a number of factors influence the selection of a dissertation topic, but not surprisingly the most important is the student's own preference. The factors affecting the choice of topics include the preference of the adviser, trends in the field, the likelihood that the research will be published, and the projected benefit of the research on the student's job prospects. The importance of the factors vary by field and in some cases by gender. When students select their topic and the extent to which the adviser and dissertation committees are responsive to the student also vary by field.
Binding of human C4 to C-reactive protein-pneumococcal C-polysaccharide complexes during activation of the classical complement pathway.

Abstract Sequential interaction of CRP-PnC aggregates, made at slight CRP excess, with purified human C1, C4 and C2 oxy resulted in formation of an effective C3-convertase, indicating the binding of C1, C4 and C2 on the aggregates. Immunoprecipitation experiments demonstrated that, following cleavage of 125 I-C4 by CRP-PnC-C1 complexes, approximately 3% of the 125 I-C4 was bound to CRP while a lower percentage was bound to PnC. CRP-C4 complexes could also be demonstrated by substituting 125 I-CRP for 125 I-C4. The nature of the CRP-C4 bond was examined by electrophoretic analysis. Complexes of 125 I-C4-CRP prepared as earlier were incubated at 100°C for 2 min in buffer containing 2% SDS and 5% β-mercaptoethanol and subjected to electrophoresis in SDS-containing polyacrylamide gradient slab gels. Autoradiography of the dried gels revealed the presence of high mol. wt bands containing the α'-chain of C4b. CRP could also be demonstrated in these high mol. wt bands which apparently represented covalent complexes between the α'-chain of C4b and CRP monomers. Since CRP contains no detectable carbohydrate, it seems likely that an amide bond is formed between the two proteins.
On-line collaborative software development via wiki

Wiki is a collaborative authoring system for collective intelligence which is quickly gaining popularity in content publication. In software development communities, especially open source and global software development teams, wiki is already widely used for documentation and coordination purpose but not programming purpose. This paper presents a new programming approach based on wiki technology by which developers are able to experience "writing wiki page is wring source code". Moreover, developers are able to compile, execute and debug programs in wiki pages too. A prototype of such on-line collaborative software development environment, Galaxy Wiki, is developed in this environment iteratively in order to prove the concept.
An intermediate filament-associated developmentally regulated protein in corneal fibroblasts

A developmentally regulated, cytoskeletal-associated protein was identified and partially characterized using a monoclonal antibody developed for this study. Based on the distinctive fibrous pattern of distribution of this antigen in the cytoskeletons of cultured corneal fibroblasts, and a characteristic reorganization of these fibers into perinuclear whorls in response to colchicine treatment, this protein was found to be associated with the intermediate filaments (vimentin filaments). Chronological distribution of this intermediate filament-associated protein (IFAP) and vimentin during fetal development of the cornea in rabbit was analysed immunohistochemically. During an early stage of corneal development (day 13 of gestation), both this IFAP and vimentin were present in the stromal cells in the presumptive corneal region. The IFAP was also present in the surface epithelium. At day 17 and 21, the corneal endothelial layer was developed and contained both the IFAP and vimentin. However, in the corneal s...
Photochemical grafting of n-alkenes onto carbon surfaces: the role of photoelectron ejection.

The grafting of molecular layers to carbon-based materials provides a way to combine the high chemical and thermal stability of these materials with surface properties such as chemical recognition or reactivity. The functionalization of surfaces with ultraviolet light has emerged as a way to modify difficult-to-functionalize materials, such as diamond. We have performed a combined experimental and computational investigation of the photochemical reaction of terminal alkenes with hydrogen-terminated carbon surfaces. 1-Alkenes carrying various terminal functional groups (−NHCOCF3, −NHCOO(tert-butyl), −COOCH3, −CH3) were grafted from the neat liquids using 254 nm light. These layers were characterized using X-ray Photoelectron Spectroscopy and Infrared Reflectance Absorption Spectroscopy. Pronounced differences in reactivity were observed between the molecules: trifluoroacetamide-terminated alkenes grafted the fastest and yielded self-terminating layers after ∼4 h. Ultraviolet photoelectron spectroscopy and...
A bound for the optimum relaxation factor for the successive overrelaxation method

An upper bound on the optimum relaxation factor for use with the successive overrelaxation method is derived for a class of linear systems arising from the numerical solution by finite difference methods of a boundary value problem involving the self-adjoint differential equation
Studies on nascent DNA in mouse myeloma

Abstract Initiation of DNA synthesis has been followed in mouse myeloma cells grown in suspension culture. In cells labeled with 3 H-thymidine for short times, label first appears in short fragments of DNA which can be chased into bulk DNA (>50 S) upon further incubation in unlabeled thymidine. In a 15 min pulse, DNA fragments with a sedimentation coefficient of 30 S tend to accumulate. Our results support the contention that DNA synthesis is discontinuous in myeloma cells. However, a search for RNA associated with nascent DNA in the myeloma system was unsuccessful. Newly synthesized DNA was isolated on a benzoylated naphthoylated DEAE cellulose column. After heat denaturation, this fraction was centrifuged to equilibrium in a Cs 2 SO 4 density gradient. The nascent DNA displays no shift in density greater than the density of the bulk DNA. When cells were pulse labeled with 3 H-uridine and the nascent DNA fraction analyzed on Cs 2 SO 4 density gradients, no 3 H-labeled RNA was found associated with the DNA peak or at intermediate densities that would be indicative of a RNA-DNA molecule, covalently linked. Unless scission of the RNA primers occurs immediately after the initiation of DNA synthesis, our results indicate that DNA synthesis commences without RNA primers in myeloma cells.
Soft tissue chondromas: diagnosis and differential diagnosis.

The authors evaluated three cases of soft tissue chondromas in patients aged 55, 57, and 78 years. Two of the lesions occurred in the foot and one in the hand. All three patients had long histories (over 1 year) of a palpable mass and all three had roentgenograms showing welldemarcated lobulated soft tissue lesions with both central and peripheral calcifications. Recognition of this rare benign chondroid lesion on imaging studies is significant since it may be misinterpreted as an aggressive lesion or a primary synovial abnormality.
The effect of particle shape and stiffness on the constitutive behavior of metal-matrix composites

Abstract This paper deals with the effective constitutive behavior of ductile metals reinforced by aligned spheroidal inclusions with linear-elastic properties. For simplicity, both the matrix and the inclusions are assumed to be incompressible and isotropic, so that the overall constitutive behavior of the metal-matrix composites is incompressible and transversely isotropic. Based on a recently proposed variational method for estimating the effective behavior of nonlinear composites, results are obtained for the initial yield surfaces and overall stress-strain relations in terms of the three essentially distinct loading modes for this class of composites : Axisymmetric tension (relative to the symmetry axis of the inclusions), longitudinal shear (along the symmetry axis) and transverse shear (perpendicular to the symmetry axis). It is found that particle shape has a significant effect on the effective response of the composites, and that this effect is markedly different for the three loading modes. For the axisymmetric mode, oblate and prolate shapes have the largest strengthening effects ; for the transverse mode, oblate shapes are most effective ; and for the longitudinal mode, nearly spherical shapes are best. Particle stiffness also has a strong effect on the initial yielding behavior of the composites, which is magnified for the more severe aspect ratios. On the other hand, the stiffness of the particles does not seem to significantly affect the stress-strain behavior of the composites for strains greater than about five times the yield value.
Growth in culture of trypsin dissociated thyroid cells from adult rats.

Summary The growth and histogenesis of grafts of intact, adult rat thyroid and trypsin dissociated thyroid cells were studied under three culture conditions; in tissue culture, as chick chorio-allantoic implants and as rat eye chamber grafts. It was found that cell mixtures from trypsinized rat thyroids have the capacity to reaggregate and reconstitute functionally active thyroid tissue. This tissue proved to be histologically identical to grafts of intact thyroids which were not trypsin digested before culture. The data further showed that the capacity of dissociated thyroid cells for reaggregation and reconstitution of functional tissue was not affected by the type of culture condition used. It was suggested that the reaggregation of thyroid epithelial cells is probably dependent on the adhesive property of the cell surface. Evidence was presented to show that this property of cell to cell binding may not be permanently altered by trypsin treatment.
Apoptotic cells quench reactive oxygen and nitrogen species and modulate TNF-|[alpha]||[sol]|TGF-|[beta]|1 balance in activated macrophages: involvement of phosphatidylserine-dependent and -independent pathways

Apoptotic cells quench reactive oxygen and nitrogen species and modulate TNF- α /TGF- β 1 balance in activated macrophages: involvement of phosphatidylserine-dependent and -independent pathways
IMMUNOREACTIVE ATRIAL NATRIURETIC POLYPEPTIDE (IRANP) CONCENTRATION IN ATRIA FROM DEVELOPING SALT-SENSITIVE (S/JR) AND SALT-RESISTANT (R/JR) DAHL RATS

Atrial natriuretic polypeptide (ANP), a substance secreted by mammalian atria in response to increased atrial pressure or volume, has potent natriuretic, diuretic and vasodilatory properties. As measured by bioassay, the ANP content in atria from adult hypertensive S/JR rats has been reported to be increased in comparison to that of adult nonhypertensive R/JR rats. In addition, the S/JR rat has been reported to be less sensitive than the R/JR rat to atrial extracts injected intravenously (Snajdar & Rapp, 1985). However, we are unaware of any data on atrial IRANP concentrations in Dahl rats of any age. Because of the potential role that ANP might play in the development of salt-sensitive hypertension, we examined the ontogeny of IRANP concentrations in S/JR and R/JR rats from 5 to 51 days of age. Atria were extracted and ANP concentrations were measured by RIA. Lactating dams consumed a diet containing 0.15% NaCl and the rat pups were weaned to the same diet. Analysis of our results to date demonstrate a significant effect of age on IRANP concentration (p<0.01) with peak concentrations occurring at 15 days of age, but no significant influence of strain. These results suggest that: 1) atrial IRANP concentrations in both strains of Dahl rat increase between 5 and 15 days of age and then decline, and 2) no difference in atrial IRANP concentration is seen between the immature S/JR and R/JR Dahl rat.
Pharmacokinetic Scale-up: Accurate Prediction of Human Pharmacokinetic Profiles from Animal Data

Ceftizoxime pharmacokinetic parameters from mice, rats, monkeys, and dogs were scaled allometrically and used to predict the value of each parameter in a 70-kg human. Three methods of interspecies pharmacokinetic scale-up provided accurate simulations of the human biexponential serum concentration-time profiles for a 1-g iv bolus and a 4-g, 30-min intravenous infusion. Successful scale-up of animal pharmacokinetic data can have tremendous impact during the preclinical assessment of new pharmaceutical compounds by providing reasonable estimates of pharmacokinetic parameters in humans.
Comparison of maternal serum total activin A and inhibin A in normal, preeclamptic, and nonproteinuric gestationally hypertensive pregnancies.

Abstract Objective: The aim of the study was to compare maternal serum levels of activin A and inhibin A in pregnancy complicated by preeclampsia, pregnancy complicated by gestational hypertension, and normal pregnancy from 25 to 42 weeks' gestation. Study Design: Activin A and inhibin A levels were measured by 2-site enzyme-linked immunosorbent assay in 60 subjects with preeclampsia, 60 control normotensive pregnant women matched for gestational age, and 51 unmatched subjects with gestational hypertension. Results: Activin A levels were higher in the preeclampsia group (median 31.5 ng/mL and interquartile range 10.5 ng/mL) than in the control group (median 10.6 ng/mL and interquartile range 9.5 ng/mL, P P P Conclusions: Levels of both analytes were greater in preeclampsia and activin A levels were greater in gestational hypertension than in normotensive pregnancy. These analytes may prove to be clinically useful laboratory markers for preeclampsia. (Am J Obstet Gynecol 1999;180:1131-7.)
Dark Energy Constraints from Galaxy Cluster Peculiar Velocities

Future multifrequency microwave background experiments with arcminute resolution and micro-Kelvin temperature sensitivity will be able to detect the kinetic Sunyaev-Zeldovich effect, providing a way to measure radial peculiar velocities of massive galaxy clusters. We show that cluster peculiar velocities have the potential to constrain several dark energy parameters. We compare three velocity statistics (the distribution of radial velocities, the mean pairwise streaming velocity, and the velocity correlation function) and analyze the relative merits of these statistics in constraining dark energy parameters. Of the three statistics, mean pairwise streaming velocity provides constraints that are least sensitive to velocity errors: the constraints on parameters degrade only by a factor of 2 when the random error is increased from 100 to 500 km/s. We also compare cluster velocities with other dark energy probes proposed in the Dark Energy Task Force report. For cluster velocity measurements with realistic priors, the eventual constraints on the dark energy density, the dark energy equation of state and its evolution are comparable to constraints from supernovae measurements, and better than cluster counts and baryon acoustic oscillations; adding velocity to other dark energy probes improves constraints on the figure of merit by more than a factor of 2. Formore » upcoming Sunyaev-Zeldovich galaxy cluster surveys, even velocity measurements with errors as large as 1000 km/s will substantially improve the cosmological constraints compared to using the cluster number density alone.« less
Weak Limits for Multivariate Random Sums

Let {Xi, i⩾1} be a sequence of i.i.d. random vectors inRd, and letνp, 0<p<1, be a positive, integer valued random variable, independent ofXis. Theν-stable distributions are the weak limits of properly normalized random sums ∑νpi=1 Xiasνp→P∞ andpνp→dν. We study the properties ofν-stable laws through their representation via stable laws. In particular, we estimate their tail probabilities and provide conditions for finiteness of their moments.
IS JUSTIFIED BELIEF KNOWLEDGE? CRITICAL NOTICE OF JONATHAN SUTTON, WITHOUT JUSTIFICATION

In Without Justification, Jonathan Sutton attempts to undermine the orthodox view that a justified belief need not constitute knowledge, develops a battery of arguments for the unorthodox thesis that you justifiably believe P iff you know P, and explores the topics of testimony and inference in light of the equation of justification and knowledge (J = K). This book is essential reading at epistemology’s cutting edge. In section I, we’ll take an extended tour of the book, raising various questions and objections along the way. In section II, we will assess Sutton’s three main arguments for J = K, which form the heart of his project.
A universal TagModule collection for parallel genetic analysis of microorganisms

Systems-level analyses of non-model microorganisms are limited by the existence of numerous uncharacterized genes and a corresponding over-reliance on automated computational annotations. One solution to this challenge is to disrupt gene function using DNA tag technology, which has been highly successful in parallelizing reverse genetics in Saccharomyces cerevisiae and has led to discoveries in gene function, genetic interactions and drug mechanism of action. To extend the yeast DNA tag methodology to a wide variety of microorganisms and applications, we have created a universal, sequence-verified TagModule collection. A hallmark of the 4280 TagModules is that they are cloned into a Gateway entry vector, thus facilitating rapid transfer to any compatible genetic system. Here, we describe the application of the TagModules to rapidly generate tagged mutants by transposon mutagenesis in the metal-reducing bacterium Shewanella oneidensis MR-1 and the pathogenic yeast Candida albicans. Our results demonstrate the optimal hybridization properties of the TagModule collection, the flexibility in applying the strategy to diverse microorganisms and the biological insights that can be gained from fitness profiling tagged mutant collections. The publicly available TagModule collection is a platform-independent resource for the functional genomics of a wide range of microbial systems in the post-genome era.
Selected physicochemical properties of the experimental endodontic sealer

This study explores water sorption, hygroscopic expansion, mechanical strength and ion release from the experimental amorphous calcium phosphate (ACP) composites formulated for application as endodontic sealers. Light-cure (LC) and dual-cure (DC; combined light and chemical cure) resins comprised urethane dimethacrylate (UDMA), 2-hydroxyethyl methacrylate (HEMA), methacryloyloxyethyl phthalate (MEP) and a high molecular mass oligomeric co-monomer, poly(ethyleneglycol)-extended UDMA (PEG-U) (designated UPHM resin). To fabricate composites, a mass fraction of 60% UPHM resin was blended with a mass fraction of 40% as-made (am-) or ground (g-) ACP. Glass-filled composites were used as controls. Both DC and LC ACP UPHM composites exhibited relatively high levels of water sorption accompanied by a significant hygroscopic expansion. The latter may potentially be useful to offset high polymerization stresses that develop in these materials. Ion release profiles of the experimental materials confirmed their potential for regeneration of mineral-deficient tooth structures. Their moderate to low mechanical strength after 3 months of aqueous immersion did not diminish the enthusiasm for the proposed use as endodontic sealers. For that application, DC g-ACP composites appear to be the most adequate, but micro-leakage and quantitative leachability studies are needed to fully establish their suitability.
Infrared-radio frequency double resonance observations of pure rotational Q-branch transitions of methane

Abstract The F 2 (2) ← F 1 (2) and F 2 (2) ← F 1 (1) transitions of the J = 7 levels of the ground state of CH4 have been observed by infrared-radio frequency double resonance using the 3.39 μ HeNe laser line. The transition frequencies are 423.02 ± 0.02 MHz and 1246.55 ± 0.02 MHz, respectively. Using these frequencies and the splitting of the E and F2 levels of the J = 2 state calculated from the molecular beam magnetic resonance spectra of Ozier, the centrifugal distortion constants are derived to be Dt = 132933 ± 10 Hz, H4t = − 16.65 ± 0.2 Hz, and H6t = 10 ± 1 Hz. The J = 15 E(1) → E(2) microwave transition is predicted as 14150 ± 9 MHz.
Gas-phase measurement of ΔH0 between axial and equatorial conformations of 3-methylcyclopentanone

Abstract The energy difference between axial-methyl and equatorial-methyl isomers of 3-methylcyclopentanone (3MCPO) was measured for the first time using resonance-enhanced multiphoton ionization spectroscopy. Variable temperature molecule beam spectroscopy was used to determine a ΔH0 of 1.19±0.14 kcal/mol which is considerably lower than the corresponding value for 3-methylcyclohexanone. This is because the 1,3-diaxial interaction between the methyl group and hydrogen atom is smaller in 3MCPO. The transition state for interconversion between the isomers of 3MCPO is calculated to lie 1.4 kcal/mol above the axial conformer energy. In spite of this small activation energy, the van’t Hoff plot shows that vibrational cooling of the conformers is much more efficient than isomerization during the supersonic expansion up to the highest temperature investigated. This means that in the molecular beam expansion, the two conformers are frozen out instantaneously.
On the Remainder in the Approximation of Functions by Bernstein-Type Operators

Let {,5,) be a sequence of linear operators on C [0, l] into C [0, 11. Evaluation of the remainder is useful in the investigation of the approximation properties of the operators&. For the Bernstein polynomials, this remainder has been thoroughly investi- gated. First, some asymptotic formulae were given by Voronovskaya and by Bernstein (see [IO], pp. 22-23) and later, the remainder was evaluated for different classes
Earth science: Volcanic cause of catastrophe.

From the timing, it looks as if an episode of marked oceanic oxygen deficiency during the Cretaceous was the result of undersea volcanism. Studies of such events are relevant to the warming world of today.
Contrast Sensitivity and English Letter Recognition

Threshold luminance contrast for letter recognition is dependent upon the amount of color contrast present, the background luminance, letter size, the age of the observer, and level of glare. Mathematical descriptions of these relationships are presented, and a model of contrast sensitivity composed of these functions is proposed. Limitations of the model, initial tests of its validity, and potential applications are discussed.
Post-natal changes in oxygen affinity and the concentration of 2,3-diphosphoglycerate in cat blood

The respiratory properties and concentrations of 2,3-diphosphoglycerate (2,3-DPG) in kitten blood were studied during fetal life and from birth to 100 days of age and compared with adult values. Fetal blood had a hemoglobin concentration (Hb) of 10.4 g%, within the normal adult range. Newborn kittens in the first 24 hr of life had Hb values averaging 13.4 g%. Hb then fell gradually, reaching a low value at about 35 days of age and subsequently rising. At 100 days of age Hb values were again similar to those of adult cats. The pH difference across the red cell membrane was significantly higher during fetal life than after birth. The P50 value for fetal blood was similar to adult blood (34.1 ± 0.6 vs. 35.2±0.8 mm Hg, respectively) but P50 values within the first 24 hr of life were significantly lower (P<0.01) than adult values. At 35 days of age, the mean P50 (37.8±1.1 mm Hg) was significantly higher (P<0.01) than for adult cats. At 100 days, P50 values were similar to adult cat blood. Concentrations of 2,3-DPG in blood from fetuses and kittens of all ages were low compared to humans and not significantly different from values of adult cat blood. The sensitivity of kitten and cat Hb to 2,3-DPG was similar and very low compared with human hemoglobin A. Starch gel electrophoresis at pH 8.6 showed no difference in kitten and adult cat Hb. Both have two major components. The fall in P50 after birth is attributed to a fall in trans-membrane pH difference, but the subsequent increase in P50 is unexplained by our data.
Dislocation interactions in strained-layer structures grown on GaAs and Si substrates

A study of dislocation behavior and an assessment of critical layer thickness in heteroepitaxial InxGa1−xAs/GaAs1−yPy (y∼2x) SLS and GaAs1−yPy layers grown by MOCVD on GaAs and Si substrates have been investigated using X-ray topography (XRT), electron beam induced current (EBIC), and transmission electron microscopy (TEM) techniques. The observations made by these techniques were compared to study the behavior of dislocations. Transmission XRT clearly showed the onset of misfit dislocations in GaAs1−yPy single layers. EBIC revealed misfit dislocations located at interfaces within the SLS. Three dimensional configuration of dislocations in the SLS were obtained by the combined use of XRT and EBIC on the same epilayers grown on GaAs substrates. It was shown by TEM that dislocations originating from the GaAs/Si interface can be forced to bend by the interfacial strain in the SLS. The dislocations that were present in a SLS grown on a Si substrate were compared to those on a GaAs substrate.
Spatial-temporal causal modeling for climate change attribution

Attribution of climate change to causal factors has been based predominantly on simulations using physical climate models, which have inherent limitations in describing such a complex and chaotic system. We propose an alternative, data centric, approach that relies on actual measurements of climate observations and human and natural forcing factors. Specifically, we develop a novel method to infer causality from spatial-temporal data, as well as a procedure to incorporate extreme value modeling into our method in order to address the attribution of extreme climate events, such as heatwaves. Our experimental results on a real world dataset indicate that changes in temperature are not solely accounted for by solar radiance, but attributed more significantly to CO2 and other greenhouse gases. Combined with extreme value modeling, we also show that there has been a significant increase in the intensity of extreme temperatures, and that such changes in extreme temperature are also attributable to greenhouse gases. These preliminary results suggest that our approach can offer a useful alternative to the simulation-based approach to climate modeling and attribution, and provide valuable insights from a fresh perspective.
Combining the Trojan Y chromosome and daughterless carp eradication strategies

The Trojan Y chromosome (TYC) strategy and the daughterless carp (DC) strategy represent two autocidal genetic biocontrol methods for eliminating invasive fish by changing the sex ratio of the population. Each strategy is designed to reduce the number of females in a target population, ultimately leading to local extinction of the population. In the DC approach, the proportion of males in the population is increased as a result of introducing an autocidal fish containing a transgenic aromatase gene insertion into multiple autosome sites. In the TYC approach, matings of an autocidal fish containing two Y sex chromosomes results in an increased proportion of males in the population. A mathematical model based upon coupled ordinary differential equations was constructed to observe the effect of an autocidal fish with the combined genetic features of both strategies (TYCDC) on a target population. The model incorporated a fitness parameter associated with fish bearing aromatase inhibitor genes and for fish bearing two Y chromosomes. Under conditions where the fitness penalty of the autocidal fish was negligible, modeling results showed that a combined strategy produced a modest reduction in the time required for female eradication, and that fewer autocidal fish were required to achieve extinction. However, increasing the fitness penalty associated with the autocidal fish neutralized the benefits of the TYCDC strategy, and suggested that the effort and expense of a combined strategy may not be warranted if the fitness cost of the TYCDC autocidal fish is significant.
Spectroscopic Investigation of Photoinduced Charge Separation and Recombination in Solid Polymers

Charge generation in polymer films following photoexcitation of charge-transfer complexes and UV two-photon ionization of aromatic dopants was studied by transient absorption spectroscopy. Charge separation from photoinduced contact ion pairs is due to the hole migration away from the geminate radical anions during the lifetime of the exciplex, which occurs by a hopping mechanism. Hole trapping at dimeric sites and subsequent charge recombination give rise to delayed exterplex emission. In resonant two-photon photoionization experiments, radical cations of aromatic molecules and excess electrons were produced as the primary charged species. The thermalization length of electrons ejected from perylene by 337-nm photons was measured as 36 A in solid polystyrene. Within the first 1 ns, reactions of electrons with polymer matrixes compete with the geminate electron−cation recombination, which leads to electron trapping and charge separation, with trapped ions stable up to milliseconds of time. Among the polym...
Barriers to Treating Obesity

Excerpt To the editors:Dr. Bray's editorial (1) elucidates some of the important barriers to treating obesity. As stated, "the public perception that obesity is a disease resulting from a lack of w...
Classical conditioning of the McCollough effect: Temporal parameters

Abstract The present paper develops a classical conditioning model of orientation specific colored aftereffects (McCollough Effects) and presents data on the temporal parameters of the CS-UCS relationship in both a delayed and trace conditioning paradigm. In this model, the lined grid in inspection is seen as the conditioned stimulus (CS) and the paired color as the unconditioned stimulus (UCS). The value of this model for further research on the McCollough Effect is discussed.
How to solve Blum's paradox

In An Essay on Free Will, Peter van Inwagen (1983: 93-95) produced a classic argument for incompatibilism, the claim that freedom and determinism are incompatible. Van Inwagen begins by assuming that, for any proposition p, it is a necessary condition of someone's being free with respect to p that she have a choice about whether p. He then goes on to argue that 'if determinism is true, then no one ever has any choice about anything' (1983: 95). In his rigorous presentation of this 'consequence' argument, van Inwagen uses 'Op' to abbreviate 'it is broadly logically necessary that p', and uses 'Np' to abbreviate 'p and no one ever has, or ever had, any choice about whether p'. The argument itself relies on the following two principles, Alpha and Beta:
Numerical approximation of generalized Newtonian fluids using Powell-Sabin-Heindl elements: I. theoretical estimates

In this paper we consider the numerical approximation of steady and unsteady generalized Newtonian fluid flows using divergence free finite elements generated by the Powell–Sabin–Heindl elements. We derive a priori and a posteriori finite element error estimates and prove convergence of the method of successive approximations for the steady flow case. A priori error estimates of unsteady flows are also considered. These results provide a theoretical foundation and supporting numerical studies are to be provided in Part II. Copyright © 2003 John Wiley & Sons, Ltd.
Judaic Perspectives on Pornography

If sexually explicit expressions are not automatically defined as obscene or illegal, moral and legal arguments must be made about what aspects of these expressions, if any, warrant restriction. According to some contemporary Jewish ethicists and rabbis, the proper Judaic response is toward greater regulations especially in regard to consuming such material. The Judaic textual tradition's vast legal and non-legal materials, however, support a more nuanced relationship to the production, distribution and consumption of erotic materials.
Effect of fat supplementation and wheat pasture maturity on forage intake and digestion characteristics of steers grazing wheat pasture.

Nine ruminally cannulated mixed-breed steers were used in a split-plot design to evaluate effects of fat supplementation and forage maturity on intake, digestibility, and ruminal fermentation. Treatment was the main plot, and stage of forage maturity was the subplot. Treatments were supplements containing mineral pack (M) offered at 114 g/d; M plus fiber as soybean hulls-wheat middlings (MF) offered at 0.50% BW; and MF plus tallow (MFT) offered at 0.625% BW. Stages of wheat maturity were mid-March (MAR) and early April (APR). Steers grazed in a single wheat pasture with supplements offered individually at 0700 h daily. There were supplement type x forage maturity interactions (P 0.05) by supplementation. During APR, forage OM, CP, and NDF intakes differed (MF = M > MFT, P MFT, P M > MFT, P MF > MFT, P APR, P 0.05) by supplement or forage maturity. Supplementation increased (P < 0.05) ruminal propionate concentration (19.7, 21.4, and 25.1 +/- 0.49 mol/100 mol for M, MF, and MFT, respectively). Tallow can be used in supplements for cattle grazing wheat pasture to increase energy intake without negatively affecting forage intake or ruminal fermentation, particularly if used in the early stage of wheat maturity.
Progressive accumulation of lanthanum in the liver of normal and uremic rats.

Progressive accumulation of lanthanum in the liver of normal and uremic rats. Background The loss of renal function in chronic kidney disease (CKD) patients leads to a variety of metabolic disturbances that promote the development of secondary hyperparathyroidism (SH) and bone disease. One of these alterations, hyperphosphatemia, is a persistent problem in patients with CKD and is an important factor in the development and severity of SH as well as coronary artery and cardiac valve calcification. To help control serum phosphorus (P), phosphate binders are used to minimize intestinal absorption of P in these patients. Since the use of aluminum- and calcium-based phosphate binders can result in severe side effects, other phosphate binders have been proposed. One of these is lanthanum (La) carbonate. Methods Since there is some controversy as to the degree La is absorbed by the intestine, whether it is deposited in tissues, and what effect its prolonged use would have in patients with chronic renal failure, we studied normal and uremic rats fed a control diet or a diet with La carbonate (1.5% elemental La) for 45, 90, or 110 days. Results As expected, plasma creatinine increased after the induction of uremia and continued to increase with time. At 45 and 90 days, dietary La produced a reduction in plasma P in normal rats (N + La) [45 days: 3.15 ± 0.35 vs. normal control (NC) 4.41 ± 0.15 mg/dL, P P P P Conclusion La accumulates in tissues, most strikingly in the liver, and renal failure accelerates the accumulation. While this was a relatively short-term study, La accumulation increased in a time-dependent manner. The effect of long-term La treatment on patients with chronic renal insufficiency needs to be evaluated.
Isotropic PCA and Affine-Invariant Clustering

We present an extension of principal component analysis (PCA) and a new algorithm for clustering points in \Rn based on it. The key property of the algorithm is that it is affine-invariant. When the input is a sample from a mixture of two arbitrary Gaussians, the algorithm correctly classifies the sample assuming only that the two components are separable by a hyperplane, i.e., there exists a halfspace that contains most of one Gaussian and almost none of the other in probability mass. This is nearly the best possible, improving known results substantially. For k>2 components, the algorithm requires only that there be some (k-1)-dimensional subspace in which the ``overlap'' in every direction is small. Our main tools are isotropic transformation, spectral projection and a simple reweighting technique. We call this combination isotropic PCA.
A Framework for Redesigning an R&D-Based National Education Dissemination System in the United States

The national education dissemination system in the United States is confusing, fragmented, and ineffective. This article suggests a framework for federal leadership in redesigning this system to enhance the use of educational research and development. The key components of the framework are education resources, dissemination functions, the bureaucratic levels at which dissemination takes place, the content or population focus related to the users' needs, and the par ticipants'roles and skills. Using this framework, the author describes the current dissemination system, possible changes in it to meet new expectations, and potential barriers and enhancers to the redesign.
Performance and radiological analyses of a space reactor power system deployed into a 1000-3000 km earth orbit

Abstract This paper presents the results of performance and radiological analyses of a space reactor power system to support space-based, radar satellites in a 1000–3000 km orbit for global civilian air and ocean traffic control. The power system with six primary and secondary loops to avoid single point failures in reactor cooling and energy conversion employs a sectored, liquid NaK-78 cooled fission reactor that has a negative temperature reactivity feedback and SiGe thermoelectric energy conversion modules, nominally generating 37.1 kWe for up to 6 years. The reactor nominally generates 1183.6 kWth at an exit temperature of ∼992 K. Thermoelectric–electromagnetic (TEM) pumps circulate the liquid NaK-78 in the primary and secondary loops and passively remove the decay heat from the reactor core after shutdown. The system parameters during the startup and shutdown transients and nominal steady-state operation are calculated. The effects of the period of incrementally inserting external reactivity on the system parameters during nominal operation are also investigated. The radioactivity buildup in the reactor during nominal operation up to 6 years and the decay in radioactivity after shutdown and as a function of storage time in orbit up to 1000 years are calculated.
A HALF-CENTURY OF URBAN GEOGRAPHY IN THE UNITED STATES

A session at the AAG meeting in 1988 was concerned with the causes and aftermath of the demise of geography at Harvard University. Several of the participants decided that it would be appropriate to review at the next meeting the development of urban geography, in which Harvard was one of the pioneers. Coincidentally, this year marked the fiftieth year of my career as a professional geographer. Therefore, this presentation includes both general observations concerning the changing character and status of urban geography and a number of personal reminiscences.
Revisiting the Role of the Fusiform Face Area in Visual Expertise

It has previously been reported (Gauthier et al., 2000, Nat. Neurosci., 3:191-197) in a functional magnetic resonance imaging (fMRI) study that objects of visual expertise (cars and birds) activate the right fusiform face area (FFA) more strongly than non-expertise stimuli, and it was argued that the right FFA is involved in expertise specific rather than face specific visual processing. This expertise effect, however, may be due to experts taking advantage of the 'faceness' of the stimuli: birds have faces and three-quarter frontal views of cars resemble faces. This expertise effect may also be caused by a biased attentional modulation: with a blocked fMRI design, experts may attend more to a block of expertise than a block of non-expertise stimuli. In this study, using both side-view car images that do not resemble faces and bird images in an event-related fMRI design that minimizes attentional modulation, an expertise effect in the right FFA is observed in both car and bird experts (although a baseline bias makes the bird expertise effect less reliable). These results are consistent with those of Gauthier et al., and suggest the involvement of the right FFA in processing non-face expertise visual stimuli.
Integration of a database system with real-time kernel for time-critical applications

Transactions in real-time database systems should be scheduled considering both data consistency and timing constraints. Since a database system must operate in the context of available operating system services, an environment for database systems development must provide facilities to support operating system functions and integrate them with database systems for experimentation. The authors chose the ARTS real-time operating system kernel. They present experience in integrating a relational database manager with a real-time operating system kernel and attempts at providing flexible control for concurrent transaction management. Current research issues involving the development of a programming interface and imprecise computing server are also discussed. >
Feature Conservation and Conversion of Tri-dexel Volumetric Models to Polyhedral Surface Models for Product Prototyping

AbstractIn this paper, detailed algorithms are presented for eliminating inconsistency in a tri-dexel volumetric models and reconstructing a water-tight polyhedral surface model from the tri-dexel volumetric model. By using the surface normal information saved in each dexel grid node, a refinement process is applied to reconstructing sharp edges and apex vertices in polyhedral surface models. The advantage of tri-dexel model is its balance in modeling accuracy and memory consumption. It is a challenge problem to convert it to a water-tight polyhedral surface model for downstream applications. The proposed techniques can be used as a geometric representation kernel in Computer-Aided Design and Manufacturing (CAD/CAM) and Computer Numerically- Controlled process simulation systems.
A PP4 phosphatase complex dephosphorylates RPA2 to facilitate DNA repair via homologous recombination

Double-stranded DNA breaks (DSBs) induce a phosphorylation-mediated signaling cascade, but the role of phosphatases in this pathway remains unclear. Here we show that human protein phosphatase 4 (PP4) dephosphorylates replication protein A (RPA) subunit RPA2, regulating its role in the DSB response. PP4R2, a regulatory subunit of PP4, mediates the DNA damage-dependent association between RPA2 and the PP4C catalytic subunit. PP4 efficiently dephosphorylates phospho-RPA2 in vitro, and silencing PP4R2 in cells alters the kinetics and pattern of RPA2 phosphorylation. Depletion of PP4R2 impedes homologous recombination (HR) via inefficient loading of the essential HR factor RAD51, causing an extended G2-M checkpoint and hypersensitivity to DNA damage. Cells expressing phosphomimetic RPA2 mutants have a comparable phenotype, suggesting that PP4-mediated dephosphorylation of RPA2 is necessary for an efficient DNA-damage response. These observations provide new insight into the role and regulation of RPA phosphorylation in HR-mediated repair.
Effects of macrophage and retinal pigment epithelial cell transplants on photoreceptor cell rescue in RCS rats

The effects of macrophage transplants on photoreceptor cell survival in retinas of Royal College of Surgeons (RCS) dystrophic rats were contrasted with RPE-cell transplants, sham-injection and surgical controls. The effects of these different treatments on the thickness and total area of the outer nuclear layer (ONL) were evaluated by light and electron microscopy at 1, 2 and 5 months after transplantation or surgical manipulations. Macrophage transplants into dystrophic retinas, although significantly reducing the debris zone thickness (p < 0.01), had little effect on photoreceptor cell survival (2-3 cells thick ONL) after two months. In contrast, two months after RPE-cell transplantation, retinas exhibited an 8-10 cell thick ONL. Also, inner and outer segments of rescued photoreceptor cells were present, especially in areas directly beneath RPE-cell transplants. At the same time period, retinas injected with saline had a 2-3 cell thick ONL with no organized inner or outer segments. Furthermore, the affe...