cssi/SciSciGPT-SciSciNet huggingface dataset:
High resolution surface plasmon resonance imaging for single cells

Surface plasmon resonance imaging (SPRI) is a label-free technique that can image refractive index changes at an interface. We have previously used SPRI to study the dynamics of cell-substratum interactions. However, characterization of spatial resolution in 3 dimensions is necessary to quantitatively interpret SPR images. Spatial resolution is complicated by the asymmetric propagation length of surface plasmons in the x and y dimensions leading to image degradation in one direction. Inferring the distance of intracellular organelles and other subcellular features from the interface by SPRI is complicated by uncertainties regarding the detection of the evanescent wave decay into cells. This study provides an experimental basis for characterizing the resolution of an SPR imaging system in the lateral and distal dimensions and demonstrates a novel approach for resolving sub-micrometer cellular structures by SPRI. The SPRI resolution here is distinct in its ability to visualize subcellular structures that are in proximity to a surface, which is comparable with that of total internal reflection fluorescence (TIRF) microscopy but has the advantage of no fluorescent labels. An SPR imaging system was designed that uses a high numerical aperture objective lens to image cells and a digital light projector to pattern the angle of the incident excitation on the sample. Cellular components such as focal adhesions, nucleus, and cellular secretions are visualized. The point spread function of polymeric nanoparticle beads indicates near-diffraction limited spatial resolution. To characterize the z-axis response, we used micrometer scale polymeric beads with a refractive index similar to cells as reference materials to determine the detection limit of the SPR field as a function of distance from the substrate. Multi-wavelength measurements of these microspheres show that it is possible to tailor the effective depth of penetration of the evanescent wave into the cellular environment. We describe how the use of patterned incident light provides SPRI at high spatial resolution, and we characterize a finite limit of detection for penetration depth. We demonstrate the application of a novel technique that allows unprecedented subcellular detail for SPRI, and enables a quantitative interpretation of SPRI for subcellular imaging.
A geometric model for the evolution of development

The idea that early developmental characters are more constrained in their evolution than late developmental characters is one of the most widely accepted generalizations about the relationship between development and evolution. It is apparent, however, that evolutionary changes do occur in early ontogeny and that understanding the nature of these changes is essential if we are to understand a variety of evolutionary phenomena, such as the origin of higher taxa. In particular, we would like to know if certain ecological conditions are more likely than others to produce changes in early development. In this paper, I present a geometric model which predicts that changes in early ontogeny should most often be fixed in environments in which the adaptive landscape is changing drastically over time. In the model, a developmental program defines a set of subsets in a space of possible mutant phenotypes, a fitness function is then imposed on this space. It is demonstrated that early developmental characters, which correspond to high dimensional subsets, are only able to evolve when the fitness function is of low curvature. If the fitness function is thought of as an adaptive landscape, low curvature corresponds to great distance from any adaptive peak. The model is then used to investigate which ecological circumstances are most conducive to evolution of the basic ways in which organisms are put together. It is shown that this model predicts the pattern of nearshore innovation which has been observed in marine paleocommunities. The results are also used to discuss the concept of “developmental constraint”. In particular, it is shown that mechanistic interactions in development can constrain the rate of evolution independently of its direction and that, in fact, this constraint on the rate of evolution may be greatest when constraints on direction are least.
Extraterrestrial digital elevation models: constraints on planetary evolution, with focus on Mars

Global digital elevation models of Mars, Venus and the Moon have been used to study the evolution of these planetary bodies and the early history of our solar system. A global digital elevation model of Mars has recently been produced from altimetry data collected by the Mars Orbiter Laser Altimeter on the Mars Global Surveyor orbiter. Over half a billion data points were collected over the five years of operation and the end result was the first centre of mass-based geodetic grid of Mars. This product has vertical resolution of ∼1 m and spatial resolution ≤500 m and has helped to define and test many hypotheses related to the planet's interior and surface evolution. Higher resolution digital elevations models (DEMs) have also been created from stereo images taken by the High Resolution Stereo Camera on the Mars Express spacecraft. These data have spatial resolution of up to 10 m, but only cover ∼25% of the planet. Both sets of DEMs have been applied to a broad range of geological and geophysical problems. Here, I focus on the application of Martian DEMs to assess the history of water on the Red Planet, which allows improved understanding of Mars' astrobiological potential.
Mace-Stoma By Caecal Flap Plasty

PURPOSE In patients with chronic constipation or fecal incontinence due to anorectal malformations, Hirschsprung's Disease, MMC and other causes, different techniques of ACE exist, depending on wheter there is an appendix or not. We describe our new technique of a stapeled caecal flap plasty in detail. MATERIAL AND METHODS During a 2 year period (2006-2008) 10 out of 30 patients underwent MACE-construction by stapeled caecal flap plasty. The mean age was 15 years (6.5-19.0). In 7 patients no appendix was present after earlier surgery. In 2 patients earlier appendicocaecostomies showed stenosis and in 1 patient the appendix was obliterated. All patients underwent stapeled caecal flap plasty and intraabdominal antirefluxive fixation. In 7 patients the ACE was fixed in the right midabdomen and in 3 in the umbilicus. RESULTS During the follow-up period 5 patients showed no problems at all. 2 had initial problems in catheterization of the MACE, 1 showed stenosis of the MACE, requiring surgical dilatation. 2 patients still show problems in the self-organisation of catheterization with delayed defecation while the stoma works well. CONCLUSIONS Our new technique of stapeled caecal flap plasty is a good alternative procedure to construct a continent catheterizable ACE-stoma in patients without appendix.
Timing of carbon emissions from global forest clearance

Agricultural expansion and deforestation contribute to approximately 17% of global greenhouse-gas emissions. The fate of cleared wood and subsequent carbon storage as wood products, however, has not been consistently estimated. Now research fills this gap and shows that 30 years after forest clearance the percentage of carbon stored in wood products and landfills ranges from about 0% to 62% globally.
Strain-specific differences in formation of apoptotic DNA ladders in MCF-7 breast cancer cells

We tested the ability of seven MCF-7 strains to undergo DNA fragmentation, as measured by DNA laddering, following doxorubicin-induced apoptosis. Four strains were found to undergo DNA laddering while three were not. All strains were inhibited by doxorubicin, although sensitivity differed. Finally, we show by detection of sub-G1 DNA that doxorubicin induced the same fold increase in apoptosis in MCF-7-ATCC, which did not ladder, and MCF-7-MG, which did ladder. Therefore, detection of DNA ladders is not an accurate indicator of apoptosis in MCF-7 cells as fragmentation of DNA appears to vary between strains.
Numerical study of a three-dimensional vortex method

Abstract A three-dimensional vortex method based on the discretization of the vorticity field into vortex vector elements of finite spherical cores is constructed for the simulation of inviscid incompressible flow. The velocity is obtained by summing the contribution of individual elements using the Biot-Savart law desingularized according to the vorticity cores. Vortex elements are transported in Lagrangian coordinates, and vorticity is redistributed, when necessary, among larger number of elements arranged along its direction. The accuracy and convergence of the method are investigated by comparing numerical solutions to analytical results on the propagation and stability of vortex rings. Accurate discretization of the initial vorticity field is shown to be essential for the prediction of the linear growth of azimuthal instability waves on vortex rings. The unstable mode frequency, growth rate and shape are in agreement with analytical results. The late stages of evolution of the instability show the generation of small scales in the form of bair-pin vortex structures. The behavior of the turbulent vortex ring is in good qualitative agreement with experimental data.
The Synthesis and Characterization of Thermotropic Liquid Crystal Model Compounds

Abstract Recently, the unique morphological classification of the “liquid crystal” state has simultaneously aroused the interest of the industrial and scientific community. With this renewed interest has come a need for better understanding and characterization of the liquid crystal transitions which occur within the many polymeric systems exhibiting this morphological phenomenon. Of the seven newly synthesized thermotropic materials for this study which are p-hydroxybenzoic acid modified compounds, six were of the rod-like geometry typically associated with mesogens. The seventh compound, a derivative of pentaerythritol, was cross-shaped and had a crystalline morphology. All compounds, including the p-hydroxybenzoic acid modified mesogenic precursor, were subjected to various characterization techniques such as proton Nuclear Magnetic Resonance (NMR), infrared spectroscopy (IR), and elemental analysis for structure determination, as well as differential scanning calorimetry (DSC), polarising microscopy e...
Cosmological perturbations in Kaluza-Klein models

Recent works have studied the classical cosmology of the early Universe in Kaluza-Klein models considered as product spaces. In this paper, the growth of cosmological perturbations is examined as a natural extension of established works concerning three-dimensional cases. Appropriate gauge-invariant quantities are defined, and the perturbed field equations are expressed in terms of these. Leading-order solutions are derived for the region in which most of the growth occurs. Difficulties with the models and the sensitivity to model variations are discussed.
Prednisolone-21 -acetate poly(glycolic acid) microspheres: Influence of matrix characteristics on release☆

Abstract The methods of freeze drying and solvent extraction-precipitation (SEP) have been employed for the preparation of prednisolone-21-acetate incorporated in poly(glycolic acid) microspheres. By maintaining a low (1 and 2%) drug loading in these delivery systems it was possible to examine the effect of the polymer matrix alone on the release characteristics of the drug. In the case of the 2% freeze-dried product, 70% released in the first 8 hours with the remaining 30% releasing more gradually over the next 64 hours. The SEP product showed a release of 89% over 8 hours followed by release of 11% over the next 64 hours. The porosity of the material, as indicated by the surface area of 12 m 2 g for the SEP product and 4–6 m 2 g for the freeze-dried product, appeared to influence the rate of release. The particle size produced by SEP was slightly larger, 48 μm, than that produced by freeze drying, 39 μm. The moisture content was 2–4% in all cases with no difference between the two methods of preparation. The drug/polymer system showed no detectable interaction between the components or the presence of any impurities. The SEP particles were found to be spherical with no surface undulations while those prepared by the freeze-drying method were nearly spherical with a distinctly crenulated surface.
Lipase-catalyzed acyiation of sugars solubilized in hydrophobic solvents by complexation.

By complexing glucose and other mono and disaccharides with phenylboronic acid, they were solubilized in many organic solvents. Pseudomonas sp. lipoprotein lipase readily acylated such solubilized sugars in these solvents (no reaction was observed without phenylboronic acid, i.e., when sugars are insoluble in the reaction medium). Solubilized D-glucose was enzymatically acylated with vinyl acrylate on a preparative scale, and the resultant 6-O-acryloylglucose was chemically polymerized to yield a sugar-based polyacrylate with a molecular weight of 14,000 Da.
When parents kill their young children: Detroit 1982-1986

The population of 36 parents or parent figures arrested for killing their children or charges, who were under the age of 6 years in Detroit, Michigan, between 1982 and 1986, are described in the context of their deadly acts. This profile of parent-on-child homicide includes demographic and social characteristics of offenders and victims, circumstances of offense, andarrest and court dispositions.
Infantile hypophosphatasia : enzymatic defect explored with alkaline phosphatase-deficient skin fibroblasts in culture

Evidence that infantile hypophosphatasia may result from defective regulation of an intact structural gene for the tissue nonspecific (bone/liver/kidney) isoenzyme of alkaline phosphatase (TNSALP) was explored by studying physicochemical properties of ALP in sonicates of monolayers of cultured dermal fibroblasts from 7 patients (PT) and 5 age- and sex-matched control (CT) subjects. Both groups had low levels of ALP activity when assayed with 4-methylumbelliferyl phosphate substrate. The mean specific activity of ALP in the PT fibroblasts was markedly subnormal (Vmax less than 1% of CT), but apparently not from extracellular loss of enzyme, since defined medium had less ALP activity when conditioned by PT compared to CT cells. Although the mean Km for the sonicate ALP was similar for both groups at pH 10.1, pH optimum, thermal stability and response to several inhibitors appeared to be different. Nevertheless, it seemed that some TNSALP-like enzyme was present in the PT group. Exposure of cells in culture to 5-azacytidine and several putative inducers of ALP failed to increase the enzyme activity in either the PT or CT groups. Had the physicochemical properties of the constitutive (or inducible) ALP been the same in the PT and CT cell groups, the findings would have provided evidence for the generality of our previous observations in one patient which indicated that defective regulation of an intact structural gene for TNSALP could account for hypophosphatasia. Our results do not, however, refute this possibility; e.g., especially minute amounts of typical TNSALP may have been present in our PT fibroblasts but were masked by (1) normal or compensatory expression of trace levels of ALP from a separate gene, (2) heterogeneity of the ALPs in the various PT (or CT) cell lines, or (3) the presence of some additional TNSALP that was different from the constitutive ALP of normal fibroblasts. Indeed, review of the findings for individual cell lines suggested that in one patient with relatively high levels of ALP activity, the physicochemical properties of this ALP was most like the enzyme in CT cells. Although further studies—including use of sensitive immunologic and electrophoretic methods—will be necessary to further characterize the minute amounts of residual ALP(s) in infantile hypophosphatasia tissues, presence of some TNSALP-like ALP in PT fibroblasts indicates that the disorder is not commonly due to a complete gene deletion for TNSALP. Our findings do indicate an especially profound and stable deficiency of typical constitutive TNSALP in fibroblasts in this disorder and suggest, therefore, that these cells might be a valuable model to explore the physiologic role of TNSALP.
Genomic data reject the hypothesis of a prosimian primate clade

The phylogenetic position of tarsiers within the primates has been a controversial subject for over a century. Despite numerous morphological and molecular studies, there has been weak support for grouping tarsiers with either strepsirrhine primates in a prosimian clade or with anthropoids in a haplorrhine clade. Here, we take advantage of the recently released whole genome assembly of the Philippine tarsier, Tarsius syrichta, in order to infer the phylogenetic relationship of Tarsius within the order Primates. We also present estimates of divergence times within the primates. Using a 1.26 million base pair multiple sequence alignment derived from 1078 orthologous genes, we provide overwhelming statistical support for the presence of a haplorrhine clade. We also present divergence date estimates using local relaxed molecular clock methods. The estimated time of the most recent common ancestor of extant Primates ranged from 64.9 Ma to 72.6 Ma, and haplorrhines were estimated to have a most recent common ancestor between 58.9 Ma and 68.6 Ma. Examination of rates of nucleotide substitution in the three major extant primate clades show that anthropoids have a slower substitution rate than either strepsirrhines or tarsiers. Our results provide the framework on which primate morphological, reproductive, and genomic features can be reconstructed in the broader context of mammalian phylogeny.
Murine streptozotocin diabetes: influences of the major histocompatibility complex, genetic background and blood transfusion.

Major histocompatibility complex-linked immune response genes are thought to influence susceptibility to induction of both human insulin-dependent diabetes and murine streptozotocin-induced diabetes. To clarify this relationship, we administered streptozotocin intravenously in two doses (120 and 240 mg/kg body weight) on days 0 and 14, and monitored blood glucose until day 100 in young adult male mice of differing background genome and/or H-2 complex. In addition, we examined the effect of allogeneic whole blood transfusion on subsequent susceptibility to diabetes. B10 recombinant mice possessing the k allele at the centromeric H-2-K and I-A loci were most susceptible to diabetes induction. Variation in susceptibility of different inbred strains with the same major histocompatibility complex genotype suggested a role for non-major histocompatibility complex genes. Blood transfusion delayed the onset, but did not significantly reduce the incidence of, delayed hyperglycaemia. We conclude that, in this murine model, multiple genes within and outside the major histocompatibility complex influence multiple-dose streptozotocin-diabetes susceptibility, and that prior blood transfusion may modulate diabetes induction.
Maternal employment and job satisfaction and their relationship to children's perceptions and behaviors

The impact of 179 mothers' maternal employment and maternal job satisfaction on their children's perceptions and behaviors was examined. The findings indicated that maternal employment was not related to job satisfaction or to children's perceptions or behaviors. Findings also indicated that maternal job satisfaction was not related to children's perceptions or their behaviors. It was hypothesized that maternal employment and maternal job satisfaction may not have the impact on family environment that has been previously suggested.
Regulatory contribution of heterotrimeric G-proteins to oocyte maturation in the sea urchin

Abstract Regulation of animal oocyte maturation is hypothesized to involve heterotrimeric G-proteins. It is difficult to test this hypothesis though without knowing what G-proteins are present in these cells and where are they localized. We set out to test the hypothesis that G-proteins regulate maturation in the sea urchin oocyte by identifying resident G-proteins in oocytes and eggs, and then investigating their function. We find four families of G-protein α-subunits (Gαi, Gαq, Gαs, and Gα12) present in both oocytes and eggs of the sea urchin. Three of them, Gαi, Gαq, and Gαs are present on the plasma membrane of the oocyte, while the fourth is located on cytoplasmic vesicles. Upon oocyte maturation, these proteins remain in eggs, and continue to be expressed in embryonic tissues. To test the functional contribution of the G-proteins to the regulation of oocyte maturation, we employ specific intervening reagents, including antibodies and competitor peptides to each Gα subunit, and specific Gα toxins. We find that Gi is a main candidate for a positive regulator of sea urchin oocyte maturation. These studies provide a foundation to further test specific hypotheses of the G-protein mediated regulation of oocyte maturation, fertilization, and early development in the sea urchin.
Highlights of VERTEX 96 Towards vertexing in 1997

Abstract A summary of the Fifth International Workshop on Vertex Detectors, VERTEX 96, is presented.
Swallowing dysfunction - Preventative and rehabilitation strategies in patients with head-and-neck cancers treated with surgery, radiotherapy, and chemotherapy: A critical review

BHARAT B. MITTAL, M.D.,* BARBARA R. PAULOSKI, PH.D., DANIEL J. HARAF, M.D., HAROLD J. PELZER, M.D., ATHANASSIOS ARGIRIS, M.D., EVERETT E. VOKES, M.D., ALFRED RADEMAKER, PH.D., AND JERILYN A. LOGEMANN, PH.D. Departments of *Radiology, Section of Radiation Oncology, Communication Sciences and Disorders, Head and Neck Surgery, Medical Oncology, and Biostatistics Core Facility, Northwestern University Feinberg School of Medicine and Robert H. Lurie Comprehensive Cancer Center, Chicago, IL; Departments of Radiation and Cellular Oncology, and Medicine, Division of Hematology-Oncology, University of Chicago Pritzker School of Medicine, Chicago, IL
DNA structure from A to Z.

Publisher Summary This chapter shows sixteen-base-pair lengths of A-, B-, and Z-DNA on a uniform scale, as a comparison and an illustration of their distinguishing features. Mean helix parameters for A-, B-, and Z-DNA as observed in single-crystal structure analyses of oligonucleotides are compared in the chapter. The A helix appears to be broader and more compressed along its axis relative to B and Z. A critical distinction is the displacement of base pairs from the helix axis. In B-DNA, the base pairs sit directly on the axis so that the major and minor grooves are of equal depth. In A DNA, the pairs are displaced off-axis in a direction that makes the major groove cavernously deep, and the minor groove extremely shallow. In Z-DNA, the base pairs are displaced in the opposite direction, yielding a deep minor groove and a major groove that is little more than a shallow depression winding around the helix cylinder.
The Polls: Attitudes Toward American Jews

CONGRESSIONAL debate in the fall of 1981 over the sale of AWACs to Saudi Arabia evoked heated public discussion, including some highly critical remarks in the media about the "Jewish lobby" and Israel's "veto" over American foreign policy. Coupled with news coverage of increasing vandalism of Jewish institutions, such stories have led some observers to conclude that there is a resurgence of antisemitism in the United States. Is there a resurgence? What do studies about the attitudes of Americans toward Jewish fellow Americans tell us? Surveying attitudes toward Jews in the United States started in the 1930s, with the triumph of the Nazis in Germany and their vigorous propaganda abroad. American Jewish organizations and individuals wanted to learn the extent of antisemitism in this country and to develop ways to counteract it. By the early 1960s over a hundred surveys of attitudes toward American Jews had been conducted. These were compiled and analyzed in Jews in the Mind of America.I Charles Herbert Stember, the editor, concluded that antisemitism was "a disappearing problem in the United States." But to this day is has not disappeared entirely. In October 1964 the Survey Research Center of the University of California at Berkeley conducted the first national survey to assess the extent and nature of contemporary antisemitism. The results were published as The Tenacity of Prejudice2 and dealt with attitudes toward discrimination in its various forms, social distance, and traditional antisemitic beliefs. Gertrude Selznick and Stephen Steinberg, who edited the volume, developed an index of 11 antisemitic beliefs which has served as a point of re-
Huxley versus Owen: the hippocampus minor and evolution

In Victorian Britain a major debate over evolution raged between Thomas H. Huxley and Richard Owen. The central issue between them was whether or not the human brain was unique in having a hippocampus minor (also known as the calcar avis), a posterior horn and a posterior lobe.
Gravimetric Evaluation of Paper Chromatograms I: Theory, Instrumentation, and Procedure

Theory, instrumentation, and procedure are given for the gravimetric determination of the distribution of compounds over an entire paper chromatogram. After the chromatogram is developed, the paper is cut into a series of 3/16-in. strips at right angles to direction of development. The portion of the sample on each strip is eluted into a tared cup. The results are graphed, using the weights of the dried residues in the cups as the ordinates and the number of the strips from the bottom of the chromatogram as the abscissas. This procedure permits the quantitation and isolation of components in low concentrations which may be missed by conventional methods of detection and eliminates the need for a reference standard for quantitative evaluation. The isolated fractions may be used for additional studies.
Perception, Corporeity, and Kindness

L'A. montre comment la phenomenologie de la perception et de la corporeite, comprise comme phenomenologie de l'incarnation, peut eclairer le phenomene de bonte, qui consiste en un certain pouvoir d'humanisation de nos relations a autrui
Functions of freedom singing in the civil rights movement: The activists' implicit rhetorical theory

This essay is an analysis of aspects of the implicit rhetorical theory held by civil rights activists. Activists held that the singing of freedom songs was an important rhetorical outlet. They ofte...
INSUFFICIENCY OF SELF-PHOSPHORYLATION FOR THE ACTIVATION OF EPIDERMAL GROWTH FACTOR RECEPTOR

Polyclonal immunoglobulins were produced against the carboxy terminus, -SEFIGA, of the receptor for epidermal growth factor (EGF). The addition of these immunoglobulins to a solution containing EGF receptor resulted in the activation of its protein tyrosine kinase. The levels of activation were assessed by measuring the initial velocities of the phosphorylation of the tyrosine in angiotensin II. The enzymatic activity induced by the immunoglobulins was significant, usually 50-70% of the maximum activity induced by EGF, and the induction occurred over a narrow range of concentration of the immunoglobulins. In order to achieve the activation, the immunoglobulins had to be bivalent; the addition of monovalent Fab fragments to EGF receptor did not produce any activation of the protein tyrosine kinase. The activation produced by the immunoglobulins was found to be reversible upon the addition of the synthetic peptide SEFIGA against which the immunoglobulins had been produced. Self-phosphorylation of the EGF receptor also occurred as the enzyme was activated by the immunoglobulins. Tryptic peptide maps demonstrated that the self-phosphorylation caused by the immunoglobulins had the same signature as that produced by EGF. When the synthetic peptide that had been used as the hapten was added to EGF receptor that had been self-phosphorylated in the presence of the immunoglobulins, the stimulated enzymatic activity was lost even though the protein remained phosphorylated. It follows from the results of deletion mutation [Walton, G. M., Chen, W. S., Rosenfeld, M. G., & Gill, G. N. (1990) J. Biol. Chem. 265, 1750-1754] and the results reported here that self-phosphorylation is neither necessary nor sufficient for the activation of EGF receptor.
CULTURED SYMBOLS / THOUGHTS ON THE CULTURAL CONTEXT OF CARTOGRAPHIC SYMBOLS

The history of cartography is so deeply embedded in ordinary map-readers by the process of development and socialization that it is simplistic to approach symbols as little more than perceptual mechanisms. Even the symbols used by three-year olds, at least with respect to hillsigns, are less perceptual than cultural products, though the embedding of the one in the other (because of the embedding of the processes of discovery, or adult development, in the processes of transmission and education) ensures that they finally represent an organic fusion of both. In mastering increasingly abstract cartographic symbols, the maturing individual masters his entire culture history, elaborated in response to both social expediency and the structure of discovery (development). In creating successful new symbols, the generative cartographer will necessarily follow a similar path. Le developpement et la socialisation de l'individu font qu'il prend pour acquis les symboles cartographiques et les considere tout au plus de...
Chemical structure of the deep atmosphere of Jupiter

Equilibrium abundances calculated for a system of over 500 compounds of 27 selected elements along a nominal Jupiter adiabat are reported. Several species predicted to be of negligible abundance in the visible upper troposphere if chemical equilibrium is exactly attained are found to be potential tracers of rapid vertical motions. Vertical mixing of certain species, especially CO, PH3, AsH3, GeS, and GeH4, may provide detectable quantities of these species near the visible cloudtops due to quenching and incomplete equilibration of the rapidly rising, rapidly cooling gas. Observational prospects for detecting such tracers of deep circulation are discussed in the light of the spectroscopic detection of CO in the 5-micron window on Jupiter and the confirmation of PH3 on both Jupiter and Saturn.
Roadblocks to competitive advantage: how organizational constraints and individual decision biases hinder investments in strategic assets

Abstract Resource-based theory suggests that unique and tacit resources may be key sources of sustainable competitive advantage. This framework is particularly compelling for technology-driven firms, where knowledge-based strategic assets are critical resources. In this paper we argue that managers pursuing a resource-based advantage are impeded by two mutually reinforcing and potentially interacting barriers: [a] structural and procedural characteristics of the resource-allocation process, and [b] individual cognitive biases in decisions involving uncertain, long time horizon investments. While the competitive challenge of implementing resource-based theory arises from the strategy literature, we describe how firms must address problems that exist at the organizational and individual levels to achieve a sustainable advantage.
Physiological adaptation of Euglena gracilis to uncouplers and inhibitors of oxidative phosphorylation.

Abstract Cells of Euglena gracilis which have adapted to growth in the presence of 2,4-dinitrophenol are at the same time resistant to the inhibitory effect on growth of carbonylcyanide m -chlorophenylhydrazone, 1,7-hexafluoro-2,6-dihydroxy-2,6- bis (trifluoromethyl)-4 hep-tanone (“1799”), oligomycin, and tri- n -butylchlorotin. Cells adapted to any of the latter are at the same time resistant to dinitrophenol. The adaptation is a response to the primary effects of the uncouplers, i.e., high levels of ADP, and not to the uncouplers per se, since arsenate induced uncoupler resistance while nonuncoupling substituted phenols did not. No evidence for any protein in the cells which can bind uncouplers tightly could be found, and no modification of reactions of isolated mitochondria could be detected. Substrate utilization by adapted cells was only slightly less efficient than in normal cells. The inhibitors were accumulated by and not excluded from the cells. Thus, the cross-resistance implies either the formation of a modified mitochondrial membrane, impermeable to these hydrophobic effectors, or an alternative or greatly modified pathway for ATP synthesis, insensitive to these effectors.
Scope of Perspective in Fertility Models

The author replies to comments by both Roth and Cashdan on his article "The First Demographic Transition." It is maintained that both critiques made use of underconceptualized fertility models. Thus Roths findings do not undermine the authors argument about the role of settlement in bringing about fertility increases; it is not settlement per se that brings about fertility increases but rather changes in diet and social relations. The question is how long such changes would take to work themselves out 10000 years ago. Similarly contrary to Cashdan there is no empirical evidence that decisions to promote or restrict fertility account for an appreciable amount of the variance in fertility between either foragers or settled cultivators. It is conceded to Cashdan however that birth control practiced for the purpose of spacing cannot be inferred from the existence of an extended age pattern of childbearing (natural fertility). To the extent that pretransition societies are concerned with birth control for spacing purposes rather than family limitation their age pattern of childbearing is likely to resemble that in natural fertility populations but will be truncated under conditions where birth spacing increases progressively with age widows remain celibate or gonorrhea is endemic. Needed are formal models that specify which variables have effects of what magnitude in which circumstances and why and how these sets of determinants change. In addition it is necessary to distinguish between micro and macro-level effects and to specify interlevel linkages.
Geochemical evidence for an initially molten Earth

Abstract The lithophile trace and major element characteristics of the upper mantle reflect crystal/liquid fractionations at high temperatures in the interior of a global magma ocean in the Earth. The combined evidence from the lithophile and siderophile elements in the mantle is indicative of a substantially molten Earth at the end of accretion. Thus, the geochemical data from the mantle support the modern theories of planetary accretion which require an initially molten Earth.
Oxygen Sensor Design: Analysis and Correction of Problems Associated with Zero Current, Stability and Structure

Membrane-covered polarographic sensors were designed by Leland Clark several decades ago. The membrane covering was a brilliant innovation because it provided an isolation of electrochemical elements from the external environment. These sensors have found a wide range of applications in many aspects of medicine, research and industry but they do not perform well at low oxygen levels because of high and unpredictable zero-current and drift characteristics. The key to overall improved zero-current and stability was a highly improved cathode seal design. Rather than heat-sealing wire into glass microtubing, a high temperature molding procedure was employed. Other improvements involved substantial modifications to the conventional methods of fixing the membrane in place, eliminating all crevices at the periphery of the membrane. This guards against potential contamination, entrapment of gas bubbles and carry over. The present sensor design can operate in gases and liquids with zero current less than 0.02% oxygen.
Quantum noise limited optical communication with low probability of detection

We demonstrate the achievability of a square root limit on the amount of information transmitted reliably and with low probability of detection (LPD) over the single-mode lossy bosonic channel if either the eavesdropper's measurements or the channel itself is subject to the slightest amount of excess noise. Specifically, Alice can transmit O(√n) bits to Bob over n channel uses such that Bob's average codeword error probability is upper-bounded by an arbitrarily small δ > 0 while a passive eavesdropper, Warden Willie, who is assumed to be able to collect all the transmitted photons that do not reach Bob, has an average probability of detection error that is lower-bounded by 1/2 - e for an arbitrarily small e > 0. We analyze the thermal noise and pure loss channels. The square root law holds for the thermal noise channel even if Willie employs a quantum-optimal measurement, while Bob is equipped with a standard coherent detection receiver. We also show that LPD communication is not possible with coherent state transmission on the pure loss channel. However, this result assumes Willie to possess an ideal receiver that is not subject to excess noise. If Willie is restricted to a practical receiver with a non-zero dark current, the square root law is achievable on the pure loss channel.
Functional analysis of Fontan energy dissipation.

We formalize the hydrodynamic energy dissipation in the total cavopulmonary connection (TCPC) using dimensional analysis and examine the effect of governing flow variables; namely, cardiac output, flow split, body surface area, Reynolds number, and certain geometric characteristics. A simplistic and clinically useful mathematical model of the dependence of energy dissipation on the governing variables is developed. In vitro energy loss data corresponding to six patients’ anatomies validated the predicted dependency of each variable and was used to develop a predictive, semi-empirical energy dissipation model of the TCPC. It is shown that energy dissipation is a cubic function of pulmonary flow split in the physiological range. Furthermore, non-dimensional energy dissipation, which is a measure of resistance of the connection, is dependent on Reynolds number and geometrical factors alone. Non-dimensional energy dissipation decreases with Reynolds number as Re � 0.25 (R 2 40.95). In addition, for high Reynolds numbers, within physiological exercise limits, dissipation strongly correlates to minimum PA area as a power law decay with an exponent of � 5/4 (R 2 40.88). This study presents a simple analytical form of energy dissipation rate in complex patient-specific TCPCs that accurately captures the effect of cardiac output, flow split, body surface area, Reynolds number, and pulmonary artery size within physiological limits. Further studies with larger sample sizes are necessary for incorporating finer geometrical parameters such as vessel curvatures and offsets. r 2008 Elsevier Ltd. All rights reserved.
Characterization and modeling of a femtosecond optical parametric oscillator suitable for tunable pump-probe spectroscopy

An improved cavity configuration continuous-wave mode-locked optical parametric oscillator (OPO) suitable for two-frequency femtosecond pump-probe spectroscopy is described. The OPO is based on intracavity pumping of a KTiOPO/sub 4/ (KTP) crystal in a colliding pulse mode-locked dye laser and produces femtosecond pulses at a 90 MHz repetition rate at average powers of 22 mW at 620 nm and 1-2 mW in the infrared. A model is synthesized from existing laser and parametric oscillator theories, and numerical simulations reproduce some qualitative aspects of the parametric oscillator's behavior. The theory accurately predicts the renormalization properties of the pump pulses in the presence of a nonlinear intracavity loss, and the existence of megahertz intensity oscillations on the output power envelope for excessively self-phase modulated pump pulses. >
Soft-edge flip-flops for improved timing yield: design and optimization

Parameter variations cause high yield losses due to their large impact on circuit delay. In this paper, we propose the use of so-called soft-edge flip-flops as an effective way to mitigate these yield losses. Soft-edge flip-flops have a small window of transparency (ranging from 0.25-3 FO4) instead of a hard edge, allowing limited cycle stealing on critical paths, and thus compensating for delay variations. By enabling time borrowing, soft-edge flip-flops allow random delay variations to average out across multiple logic stages. In addition, they address small amounts of delay imbalance between logic stages, further maximizing the frequency of operation. We develop a library of soft-edge flip-flops with varying amounts of softness. We show that the power and area overhead of soft-edge flip-flops grows directly with the amount of softness. We then propose a statistically aware flip-flop assignment algorithm that maximizes the gain in timing yield while minimizing the incurred power overhead. Experimental results on a wide range of benchmark circuits show that the proposed approach improves the mean delay by 1.9--22.3% while simultaneously reducing the standard deviation of delay by 1.9--24.1% while increasing power by a small amount (0.3--2.8%).
King Herod in Ardashir's Court: The Rabbinic Story of Herod (B. Bava Batra 3b–4a) in Light of Persian Sources

The Bavli's story of Herod's rise to power, murder of the Hasmonean family and of the rabbis, encounter with Bava b. Buta, and construction of the temple, found at Bava Batra 3b-4a, has long puzzled scholars. Many aspects of this story diverge from Josephus's account, our main source for historical knowledge of Herod's life and deeds. This paper argues that the storyteller has been influenced by Persian sources from the Sasanian period. Important elements of the Bavli story were modeled on the account of the rise of Ardashir, founder of the Sasanian dynasty, as recounted in a Sasanian text known as the Karnamag i Ardashir i Pabagan, “The Book of the Deeds of Ardashir son of Pabag.” The rabbis understood the transition from the Hasmonean to Herodian dynasties through the prism of the transition from the Parthian to Sasanian dynasties. They identified Herod with Ardashir, and constructed a story of Herod's usurpation and rise to power on the basis of Ardashir's usurpation and rise to power as recounted in Sasanian sources.
Transformation of DDT and Its Metabolites by Various Abiotic Methods

This work looks at several new abiotic treatment methods for transformation of DDT in an aqueous solution. Various combinations of calcium peroxide (Ca O2 ) , zero-valent iron ( Fe0 ) , iron sulfide (FeS), and hydrogen peroxide ( H2 O2 ) were utilized to promote the abiotic transformation of 1,1,1-trichloro-2,2-bis( p -chlorophenyl)ethane (DDT) in electrolyte, hydroquinone, and nonionic surfactant (Triton X-114) systems. Treatment with Ca O2 resulted in 86% DDT mass reduction within 10 days of treatment with only traces of 1,1-dichloro-2,2-bis( p -chlorophenyl)ethane (DDD) , 1,1-dichloro-2,2-bis( p -chlorophenyl)ethylene (DDE), and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDMU) being generated. Treatments with 1:1 mixtures of Fe0 :Ca O2 and FeS:Ca O2 resulted in 86 and 85% DDT mass transformation, respectively, within 8 days . A mixture of 0.75 g Fe0 :0.1 g Ca O2 showed similar results with 79% DDT mass transformed within 8 days . A mixture of 0.75–0.1 g of Fe0 :FeS resulted in 85 and 97% transformat...
Three Mercantilistic Proto-Factories

The role of “proto-factories” in the industrial development of eighteenth-century Europe is explored through comparison of three Bohemian examples.
A study of alternate stochastic models in Kushner-based global optimization methods

The use of alternative stochastic models (other than the Brownian motion process) in conjunction with H.J. Kushner's loss function (1963) is explored. The following stochastic process models are considered: the process of G.E. Uhlenbeck and L.S. Ornstein (1930); Brownian motion with drift; geometric Brownian motion; and fractional Brownian motion. The geometric Brownian motion model is shown to be the most attractive of the selections since a closed-form solution exists, an n-dimensional simplex-based extension can be developed, and no parameters need to be estimated or prespecified. It is also shown that the Ornstein-Uhlenbeck process and fractional Brownian motion yield searches equivalent to the standard Brownian method for limiting values of their parameters. >
A Martingale Characterization of Consumption Choices and Hedging Costs with Margin Requirements

This paper examines optimal consumption andinvestment choices andthe cost of hedging contingent claims in the presence of margin requirements or, more generally, of nonlinear wealth dynamics andconstraints on the portfolio policies. Existence of optimal policies is establishedusing martingale and duality techniques under general assumptions on the securities’ price process and the investor’s preferences. As an illustration, explicit solutions are provided for an agent with “logarithmic” utility. A PDE characterization of the cost of hedging a nonnegative path-independent European contingent claim is also provided.
Persistent photoconductivity in SIMOX films

Photoinduced transient spectroscopy (PITS) was used to measure the persistent photoconductive (PPC) response in film resistors fabricated on two different commercial n-type SIMOX (separation by implantation of oxygen) wafers. A broadband, single-shot, flashlamp-pumped dye-laser pulse was used to photoexcite interband electrons in the film, and the decay of the induced excess carrier population was measured at temperatures in the 60-220 K range. The post-illumination conductivity transients observed show PPC signals exhibiting a nonexponential character. They were recorded for periods of time up to 30 s at constant temperature. Presented are the excess conductivity in SIMOX film annealed in nitrogen at 1300 degrees C for 6 h and the hole-trap volume density at the conductive-film-buried-silicon interface. >
Women in CS and biology

Common departmental characteristics and practices in computer science and biology/life science are compared for 46 departments at 23 Virginia colleges and universities. The goal of this preliminary investigation is to provide additional evidence on how departmental factors can affect the retention of female students.
Spontaneous regression of a rare tumour in a child: angiolymphoid hyperplasia with eosinophilia of the hand: case report and review of the literature.

Summary Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon benign, idipathic vasculoproliferative condition manifested by multiple or solitary subcutaneous nodules, usually in the head and neck region of young adults. It is very rare in the extremities especially in the hands. Although recurrence is common, surgical excision is still regarded as the treatment of choice. We report an 11-year-old girl with histologically confirmed ALHE on the dorsum of her left hand, which underwent complete spontaneous regression within 10 weeks. Angiolymphoid hyperplasia is a benign disease and it is important to recognise this condition so that early superficial lesions can be observed for 3–6 months pending spontaneous regression.
Intermolecular interactions in linear and nonlinear susceptibilities: beyond the local-field approximation

Reduced equations of motion for material and radiation field variables in a molecular crystal are presented that allow us to calculate linear- and nonlinear-optical susceptibilities, accounting in a systematic way for intermolecular interactions. These equations are derived starting from the multipolar (μ · D) Hamiltonian, and to second order in the molecular dipole they reduce to the Bloch–Maxwell equations with local-field corrections. The dielectric function obtained through our approach incorporates retarded interactions in a consistent way and is compared with the existing exciton polariton theory, which is based on the minimal coupling (p · A) Hamiltonian. We find that, unlike with the conventional polariton theory, spontaneous emission is not suppressed in an infinite crystal.