cssi/SciSciGPT-SciSciNet huggingface dataset:
Market Dominance in the Digital Age: Online Feedback Loops and Rising Industry Concentration

I document that online feedback loops, such as search engines, drive customers and revenues to prominent firms. This creates barriers to entry, weakening competition and contributing to rising industry concentration. To identify prominent firms online, I measure centrality in a network of firm websites covering more than 100,000 public and private firms. Industries with firms that are more central become more concentrated and central firms increase their market share during the sample period. This appears to be due to firms' ability to generate revenues. Central firms become more profitable and peripheral firms earn negative risk-adjusted returns and underperform earnings forecasts. Evidence from the COVID-19 shutdown, which drove economic activity online, supports these conclusions. Central firms received the vast majority of the influx of web traffic and had significantly higher returns during the shutdown. My results highlight the difficulties of maintaining competition in an increasingly digital economy.
Identification of a fibroblast growth factor-binding protein in Drosophila melanogaster.

Abstract As assessed by competitive binding and protein-crosslinking experiments, Drosophila melanogaster cells possess basic fibroblast growth factor (bFGF)-specific binding proteins that are similar to FGF receptors on vertebrate cells in molecular weight and binding affinity; these D. melanogaster cells, however, have no detectable binding proteins for acidic fibroblast growth factor (aFGF). Consistent with the presence of bFGF-specific binding proteins, D. melanogaster cells degrade bFGF but not aFGF. These results indicate the conservation of heparin-binding growth factors and receptors between vertebrates and D. melanogaster.
Metabolism of 6-Mercaptopurine by Resistant Escherichia coli Cells.

Abstract Coggin, Joseph H. (University of Chicago, Chicago, Ill.), Muriel Loosemore, and William R. Martin. Metabolism of 6-mercaptopurine by resistant Escherichia coli cells. J. Bacteriol. 92:446–454. 1966.—6-Mercaptopurine (MP) utilization as a source of purine in MP-sensitive and -resistant cultures of Escherichia coli was investigated. The label of MP-8-C14 appeared in adenine and guanine of ribonucleic acid and deoxyribonucleic acid in sensitive and resistant cultures. Studies using MP-S35 further demonstrated that the MP moiety was degraded, as shown by a rapid decrease in radioactivity from cells upon exposure to MP for 20 min. Enzymatic analysis showed that MP was converted to 6-mercaptopurine ribonucleotide (MPRP) by extracts derived from both sensitive and resistant cells. Resistant cell preparations, however, degraded MPRP to inosine monophosphate (IMP) rapidly when compared with analogue degradation by sensitive cells. Inosineguanosine-5′-phosphate pyrophosphorylase from resistant cells did not catalyze the synthesis of IMP from hypoxanthine when the cells were cultured in the presence of MP, but these enzyme preparations actively converted guanine to guanosine monophosphate (GMP). Pyrophosphorylase derived from resistant cells cultured in medium without MP catalyzed the conversion of hypoxanthine to IMP and also guanine to GMP. These observations suggest that inosine-guanosine-5′-phosphate pyrophosphorylase is composed of two distinct enzymes. The mode of resistance to MP in E. coli is related to an enhancement of the enzymatic degradation of MPRP to the pivotal purine intermediate, IMP.
The design of failure: health policy and the structure of federalism.

This paper explores the impact of the federal structure of American government on health policy through the examination of three case studies of unsatisfactory policy: Medicaid cutbacks; provider licensure; and health planning under P.L. 93-641. Problems arise in three areas because of a disjunction between administrative or regulatory responsibilities and financial accountability. How the division of responsibilities among different levels of government might be managed better is examined briefly, in the context of possible state roles under a system of national health insurance.
Partial FFT Demodulation: A Detection Method for Highly Doppler Distorted OFDM Systems

Employing Orthogonal Frequency Division Multiplexing (OFDM) signaling over time-varying channels results in inter-carrier interference (ICI) and degraded detection error probability due to the loss of orthogonality among the subcarriers. This problem is particularly exacerbated for systems operating in highly mobile scenarios such as underwater acoustic (UWA) communications, digital video broadcasting (DVB) for mobile devices and vehicle-to-vehicle (V2V) networks. To address the problem of data detection in such scenarios, we propose a novel demodulation strategy using several partial interval Fast Fourier Transforms (FFTs) instead of a conventional, single full interval FFT. Algorithms for computing the weights used to combine the outputs of the partial FFT are presented for three scenarios: full, partial and no knowledge of the time varying channel. Numerical simulations and an approximate theoretical analysis show that significant performance gains can be obtained over traditional equalizers at a very moderate complexity.
Inhibition of human platelet aggregation and secretion by ant venom and a compound isolated from venom.

Venom from the tropical ant,Pseudomyrmex. triplarinus, has activity against rheumatoid arthritis. Since platelets are involved in inflammatory responses, they were employed to study the effects of venom on prostaglandin-dependent human platelet aggregation and secretion. The assay is very sensitive and uses microliter volumes, which makes it useful as a screen during isolation and characterization of venom components. Whole venom inhibited arachidonic acid- and U46619-induced platelet aggregation with IC50s of 45 and 39 μg/ml, respectively. This suggested that venom prevented the action of prostaglandins. Pure venom was fractionated by gel filtration and at least three materials with antiplatelet activity were detected. The smallest component (factor F) was most active and was purified by additional molecular filtration and characterized by UV absorbance, thin-layer chromatography, nuclear magnetic resonance spectra, and activity to platelets. Factor F was identified as adenosine, which is known to stimulate platelet adenylate cyclase and has not been previously reported to be a component of insect venom.
Applying anxiety\uncertainty management (AUM) Theory to intercultural adjustment training

Abstract The purpose of this article is to illustrate how anxiety\uncertainty management (AUM) theory can be applied to intercultural adjustment training and to examine the role of individualism–collectivism in training within this theoretical perspective. Initially, the theory, as applied to intercultural adjustment, is summarized briefly. Next, a seven session training program based upon the theory is suggested. Cultural similarities and differences in individualism–collectivism are discussed as ways to help trainees manage their uncertainty.
Reaction between Metabolically Activated Acetaminophen and Phosphorothioate Oligonucleotides

Assessment of toxic or mutagenic risks associated with phosphorothioate oligonucleotides (PTO) is important. In vitro and in vivo data have shown that PTOs are nontoxic and nonmutagenic. However, these studies do not address interactions between PTOs and other compounds. The sulfur on PTOs may provide a novel reactive center on a DNA molecule for drug interactions. This study chose acetaminophen (ACAP) as a model drug because ACAP is oxidized to the reactive intermediate N-acetyl-p-benzoquinone imine (NAPQI), which reacts with sulfur-containing compounds. Reaction of dCTP(S) with NAPQI or activated ACAP formed a product distinct from the reactants. Analysis of the product by fast atom bombardment mass spectroscopy gave a molecular weight consistent with NAPQI bound to a sulfur. Higher-molecular-weight products were seen on a polyacrylamide gel electrophoresis after incubation of fluorescein-labeled PTO with NAPQI. These products were not seen after incubation of a phosphodiester oligonucleotide with NAPQI. 31P NMR analysis confirmed the existence of a heterogenous mixture of adducts between a PTO and NAPQI. Nonsequence-specific PTOs of various lengths were tested for their ability to reduce ACAP toxicity. Cell viability showed that larger PTOs provided greater protection. We evaluated the ability of NAPQI to cause mutations in the LacZ gene of pBluescript plasmid which contained phosphorothioate linkages at designed locations within the gene. In addition, the ability of ACAP to cause mutations in the HGPRT locus in cells grown in dATP(S)-containing medium was measured. No mutations were seen in either assay. Based upon these results, activated ACAP is reactive with PTOs in vitro, although this interaction is nontoxic and nonmutagenic.
Live-attenuated HIV vaccines: how safe is safe enough?

A live-attenuated SIV vaccine inducing protection in healthy adult monkeys appears both safe and effective but may be lethal when given in high doses to newborns (pages 32−36).
Biochemical changes induced by tumors at distant sites: altered transfer RNA profiles in livers of mice bearing plasmacytomas.

Abstract Tumor growth is known to have systemic effects upon the host's metabolism. We report here for the first time that histologically normal livers of mice bearing subcutaneous plasmacytomas contain chromatographic peaks of asparaginyl-, aspartyl-, histidinyl-, and tyrosinyl-transfer RNAs not found in significant amounts in normal livers. Lysyl-, prolyl-, seryl-, threonyl-, tryptophanyl-, and valyl-transfer RNAs, from plasmacytomas also have chromatographic profiles different from normal tissues, but these tRNAs are not altered in livers of tumor bearing mice. This suggests that distant tumor growth causes a derangement in one of the liver enzymes that normally modify transfer RNA after transcription.
FORMAL AND INFORMAL SECTORS IN CHINA AND INDIA

This paper discusses the estimation of a social accounting matrix that distinguishes between formal and informal activities for China and India for 2000 and 1998–99 respectively. Wage shares for formal/informal employment in China and net domestic product shares for organized/unorganized sectors in India are used as weights to calculate the size of the two sectors. The proposed methodology is a first step towards an integrated approach to account for the dualism of many economies in the developing world. The results can serve as data input for any policy-driven CGE model for developing countries.
Colony stimulating factor-1 expression in human glioma

Colony stimulating factor 1 (CSF-1) is a functionally versatile, circulating homodimeric growth factor that stimulates the survival, proliferation, and differentiation of mononuclear phagocytic cells, the differentiation of osteoclast progenitor cells and that regulates cells of the female reproductive tract. CSF-1 is also expressed in the central nervous system where it may regulate the differentiation and activation of microglia. The diverse forms of CSF-1 are all encoded by a single gene. Alternative posttranscriptional splicing and posttranslational cleavage determines whether CSF-1 will be produced as a secreted proteoglycan, secreted glycoprotein, or as a cell-surface glycoprotein that may be involved in cell-cell interactions. CSF-1 is expressed in glioblastoma cell-lines, normal human astrocytes, and in operative specimens of human glioma. The CSF-1 receptor, encoded by the c-fms proto-oncogene, is also expressed in human gliomas. We conclude that coexpression of CSF-1 and its receptor in some human gliomas hints at a possible autocrine or paracrine growth stimulatory role for CSF-1; however, its function in the mammalian CNS remains to be elucidated.
Is there a magnitude effect in tipping

The present study examined nearly 1,000 tips recorded for two taxicabs, two hair salons, and two restaurants. In each of the six cases, amount of tip increased linearly as a function of the amount of the bill. Contrary to standard microeconomic theory, there was a magnitude effect in that as the amount of the bill increased, the percent tip tended to decrease. The present results extend the findings of Chapman and Winquist (1998), obtained using hypothetical scenarios, to real-world tipping behavior. Chapman and Winquist argued that a magnitude effect in tipping reflects the shape of the utility function for money. We suggest, however, that the magnitude effect may be the mathematical consequence of replotting the fundamental relationship between tip and bill amounts in terms of percent tip, given that the observed linear relation between tip and bill amounts has a positive intercept. We suggest further that the positive intercept arises because a tip represents a judgment as to what constitutes a fair or equitable wage, and part of what constitutes a fair wage is independent of the amount of the bill, reflecting compensation for simply being there when needed. The present account implies that different explanations may be needed for magnitude effects observed in different domains.
Policy undertakings by the seven “summit” countries: ascertaining the degree of compliance

Abstract This paper sifts through the economic-summit declarations, issued annually since 1975, to determine how credible the announced government commitments would have deserved to be, judging by the degree to which they have been fulfilled. Measuring compliance with fuzzy undertakings imposing imprecise obligations was assisted by fitting nonlinear membership functions to allow partial credit. The average scores assigned to the 203 undertakings that could be evaluated through 1989 were so low that the joint null hypothesis of “no summit ambition” and “no summit effect” could barely be rejected. However, there were notable differences by summit, country, and type of issue.
Managing Archival Collections in an Automated Environment: The Joys of Barcoding

In a desire for automated collection control, archival repositories are adopting barcoding from their library and records center colleagues. This article discusses the planning, design, and implementation phases of barcoding. The authors focus on reasons for barcoding, security benefits, in-room circulation tracking, potential for gathering statistics, collection control, and timeline development. They discuss the implementation of one university's barcoding project, addressing issues involving database reports, physical barcoding issues, the problems encountered with different kinds of inaccuracies, and the pitfalls to avoid for a successful outcome.
Colorimetric Approach to Cyanobacterial Off-Flavor Detection

A colorimetric method to quantify methylisoborneol and geosmin in water and fish flesh based on a spot test by Wood and Snoeyink was developed. To test water samples, one liter of filtered water is pumped through a solid phase extraction device and the off-flavor eluted from the device with toluene. The toluene is combined with a 1 percent vanillin in concentrated sulfuric acid and agitated for 30 min to produce the color change. The standard solution is yellow and at increasing concentrations of 2-methylisoborneol or geosmin the color changes from light orange to blood red. Extraction from 1 liter of water results in a sensitivity of 1 ppb. This is suitable for quality control of seafood. For use in measuring action levels (high and low ppt levels for aquaculture and drinking water, respectively), extraction from greater volumes will be required.
Expert System for Design of Low-Volume Roads over Expansive Soils

This paper summarizes the development of an expert system to assist pavement engineers in designing more realistic and practical low-volume roads in clayey areas. This expert system combines numerical and engineering analyses with heuristic information about the site to recommend optimal design, remediation, and construction alternatives. Common distress types are considered. In particular, numerical analysis is incorporated to predict the potential for longitudinal cracking of the section, which was reported in a survey throughout Texas to be the most prevailing distress. After assessment of the structural capacity, remediation methods are proposed to address the problem of premature failure of low-volume roads on clays with a high plasticity index. Cost-benefit analyses are added to compare cost-effectiveness of recommended alternative strategies. Finally, a case study is presented in detail to illustrate the use of the software. A preliminary study of typical low-volume roads built over expansive subso...
The mixed alkali effect: Theoretical considerations

Abstract A cooperative theory for the composition dependence of activated processes in binary ionic oxide glasses (the mixed alkali effect) is proposed. It employs the regular solution model and introduces a molecular model, both of which are used in conjunction with appropriate spectroscopic data for obtaining an estimate of the magnitude of the theory's parameters. The nonlinear composition dependences of certain physical properties of mixed alkali systems, as well as their separation into exponential and pre-exponential factors, are shown to follow from these theoretical considerations.
A semantically-adaptive strategy for energy-efficiency in wireless medical monitoring devices

We propose a novel strategy for energy-efficient operation of wireless monitoring devices under the premise that medical experts are primarily interested in atypical observations - For epilepsy monitoring, EEG data is most valuable at epileptic activity onset. Or, a gait-stability monitoring application is most interested in unusual footsteps. Observations are atypical if application-specific medical metrics and biosignal features are statistical outliers. Our strategy admits energy-efficient early-detection of such observations, leading to: (i) an increase in medical information quality by sampling aggressively over semantically important behaviors, and (ii) a savings in energy by precluding communication of typical measurements. From experimentally collected plantar pressure datasets, we show that this can yield up to a 62% improvement in gait-stability metric evaluation for atypical footsteps and a 10% energy cost reduction compared to a recently proposed non-adaptive compressive sensing technique.
Translocation and mechanical spread of a Minnesota isolate of potato virus S in potatoes

Potato cultivars Norland, Kennebec, and Russet Burbank were inoculated with a Minnesota isolate of potato virus S (PVS) in the field. The incidence of secondary infection, measured by enzyme-linked immunosorbent assay (ELISA), indicated that significantly more PVS infection occurred in Russet Burbank than Norland or Kennebec, and that Norland had significantly more infection than Kennebec (P≤ 0.01). Mature plant resistance was not observed. Rapid reinfection of PVS-free seedlots resulted from inoculum point-sources when routine cultivation practices were followed. Reinfection rates were significantly greater for seedlots grown at Grand Forks, ND, when compared with seedlots grown at Becker, MN, during both years of the study (P≤ 0.01). After two years in the field, reinfection rates for Norland (71.8%) and Russet Burbank (73.0%) did not differ significantly, but were significantly greater than the reinfection rate for Kennebec (29.5%) (P≤ 0.01). In greenhouse-grown plants, PVS moved out of rub-inoculated leaves within 24 hr, however, 13 and 20 days were required before PVS was detected with ELISA in foliage above and below the inoculated leaf, respectively. The frequency of PVS detection was significantly greater in foliage above the inoculated leaf compared to foliage below the inoculated leaf (P≤ 0.05). Translocation of PVS from inoculated leaves to daughter tubers occurred within 13 days for Russet Burbank and Norland and within 20 days for Kennebec.
Does reaching in the dark for unseen objects reflect representation in infants

Five groups of 7-month-old infants had varying amounts of experience with a sounding object in the light before being presented with it in the dark. Neither visual nor auditory experience was necessary for accurate reaching in the dark, suggesting that infants represented the unseen object.
Application of dynamic line narrowing in resonant optical sensing

We propose a dynamic operational mode and the resulting dynamic line narrowing as a method for enhancing the resolution and the detection limit of high-quality (high-Q) resonant optical sensors. Using a silica microtoroid as an experimental platform, we demonstrate that dynamic line narrowing through the thermo-optic effect can significantly improve the detection limit in both resonant shift and resonance splitting operating modes.
Bed Bugs and Infectious Disease: A Case for the Arboviruses

This work was funded by the Fralin Life Science Institute at Virginia Tech, as well as the College of Agriculture and Life Sciences and the Department of Entomology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Property Rights and Entrepreneurial Income in Commercial Fisheries

Abstract Entrepreneurs who own and operate fishing vessels oppose conversion of open access fisheries to sole ownership and oppose Pigouvian taxes on landings because those policies reduce their incomes. Government buybacks of quotas and self-financed quota reductions increase their incomes. Under specified conditions with transferable quotas, optimal harvesting is a Lindahl equilibrium and a sequence of elections will converge on the Lindahl equilibrium.
Letting go of the mouse: using alternative computer input devices to improve productivity and reduce injury

Many computer related injuries occur from mouse use. The mouse is the primary input device by virtue of its universal availability, yet it is not the best for all‐round work. Alternative devices such as the track ball, touch pad, and graphics tablet can be used more effectively for precise cursor control, while reducing stress and the potential for injury. Though these devices may seem exotic or a luxury, they are in fact affordable and well‐suited to daily use by everyone. This article describes the mouse and its inherent weaknesses, and offers more practical alternatives. These alternatives may help reduce injury‐producing activities, and may also improve productivity and creativity by allowing more precision cursor controls.
Large-scale constriction and segregation of polar lobes from the eggs of Mytilus edulis.

Abstract Polar lobes become constricted from the eggs of Mytilus edulis in hypertonic solutions of various monovalent and divalent salts and nonelectrolytes. This technique may be used for obtaining large numbers of isolated polar lobes. The effectiveness of a variety of substances indicates that the basic mechanism is related to a dehydration of the cytoplasm, although there may be secondary effects of specific cations. The elutriation principle, used for sediment analysis, has been adapted for segregation of polar lobes which have been separated from whole eggs and cleavage stages. The essential feature of this method is an ascending flow of water which causes segregation of cells of different sizes according to their respective fall velocities.
Phosphorus distribution in sediments of the Delaware River estuary

In order to determine the primary factors related to the accumulation of phosphorus in estuarine sediments, a study of phosphorus fractions in sediments of the Delaware River Estuary was undertaken. A correlation matrix between the phosphorus fractions, determined by serial extraction, and 14 sediment variables was computed. Total phosphorus and total inorganic phosphorus in the sediment-phosphorus reservoir decreases with increasing salinity. This variation is correlated with decreasing iron oxyhydroxide content in the sediment. Neither clay content nor calcium carbonate content appear to be significantly correlated with variation in total inorganic phosphorus content in the fine-grained sediments of this estuary. Although calcium phosphate is concluded to be a major constituent of the sediment-phosphorus reservoir, there was no evidence found that it is authigenic in this environment.
The standard reference model in the AIMI and TEXPLAN systems

In this article, we describe the presentation components of two systems created at The MITRE Corporation: An Intelligent Multimedia Interface (AIMI) and the Textual Explanation PLANner (TEXPLAN) system. We then describe and analyze these two systems using the Standard Reference Model (SRM) for Intelligent Multimedia Presentation Systems (IMMPS) [M. Bordegoni, G. Faconti, S. Feiner, M. Maybury, T. Rist, S. Ruggieri, P. Trahanias, M. Wilson, A standard reference model for intelligent multimedia presentation systems, Computer Standards and Interfaces, 18 (6,7) 477-496].
Gravity wave observations in the summertime polar mesosphere from the Cloud Imaging and Particle Size (CIPS) experiment on the AIM spacecraft

Abstract We present the first results of gravity wave signatures on polar mesospheric clouds (PMCs) during the summer of 2007, in the northern hemisphere polar region. The Cloud Imaging and Particle Size (CIPS) experiment has one of the three instruments on board the NASA Aeronomy of Ice in the Mesosphere (AIM) spacecraft, which was launched into a sun-synchronous orbit on April 25, 2007. CIPS is a four-camera, wide-field (120°×80°) imager designed to measure PMC morphology and particle properties. One of the objectives of AIM is to investigate gravity wave effects on PMC formation and evolution. CIPS images show distinct wave patterns and structures in PMCs that are similar to ground-based photographs of noctilucent clouds (NLCs). The observed horizontal wavelengths of the waves were found to vary between 15 and 320 km, with smaller-wavelength structures of less than 50 km being the most common. In this paper we present examples of individual quasi-monochromatic wave events observed by CIPS and statistics on the wave patterns observed in the northern hemisphere during the summer months of 2007, together with a map showing the geographic locations of gravity wave events observed from CIPS.
Advances in spatial data infrastructure, acquisition, analysis, archiving & dissemination

The authors review recent contributions to the state-of-thescience and benign proliferation of satellite remote sensing, spatial data infrastructure, near-real-time data acquisition, analysis on high performance computing platforms, sapient archiving, multi-modal dissemination and utilization for a wide array of scientific applications. The authors also address advances in Geoinformatics and its growing ubiquity, as evidenced by its inclusion as a focus area within the American Geophysical Union (AGU), European Geosciences Union (EGU), as well as by the evolution of the IEEE Geoscience and Remote Sensing Society's (GRSS) Data Archiving and Distribution Technical Committee (DAD TC).
Thalamocortical Long-Term Potentiation Becomes Gated after the Early Critical Period in the Auditory Cortex

Cortical maps in sensory cortices are plastic, changing in response to sensory experience. The cellular site of such plasticity is currently debated. Thalamocortical (TC) projections deliver sensory information to sensory cortices. TC synapses are currently dismissed as a locus of cortical map plasticity because TC synaptic plasticity is thought to be limited to neonates, whereas cortical map plasticity can be induced in both neonates and adults. However, in the auditory cortex (ACx) of adults, cortical map plasticity can be induced if animals attend to a sound or receive sounds paired with activation of cholinergic inputs from the nucleus basalis. We now show that, in the ACx, long-term potentiation (LTP), a major form of synaptic plasticity, is expressed at TC synapses in both young and mature mice but becomes gated with age. Using single-cell electrophysiology, two-photon glutamate uncaging, and optogenetics in TC slices containing the auditory thalamus and ACx, we show that TC LTP is expressed postsynaptically and depends on group I metabotropic glutamate receptors. TC LTP in mature ACx can be unmasked by cortical disinhibition combined with activation of cholinergic inputs from the nucleus basalis. Cholinergic inputs passing through the thalamic radiation activate M1 muscarinic receptors on TC projections and sustain glutamate release at TC synapses via negative regulation of presynaptic adenosine signaling through A1 adenosine receptors. These data indicate that TC LTP in the ACx persists throughout life and therefore can potentially contribute to experience-dependent cortical map plasticity in the ACx in both young and adult animals.
Political-economic structures—Approaches to traditional and modern medical systems

Abstract The paper is concerned with the WHO-UNICEF suggestion to train indigenous healers to be first-line deliverers of medical care. Rather than evaluate this proposal directly, the paper concentrates instead on the factors currently influencing the relationship between indigenous and Western medicine. A framework, viewing the potential health impact of the use of indigenous healers, is constructed through the comparative method [6]. Data reviewed consists of monographs, journal articles, dissertations. etc., and considers historical, cultural, and political theories of the status of native medicine. The paper concludes that the politics of health care is a greater impediment to the provision of “health care for all” in some types of political economic systems than in others. Thus events in the health care system as seen as influenced by the larger socio-political system.
SKIN AND SOFT TISSUE NECROSIS FROM CALCIUM CHLORIDE IN A DEICER

Calcium chloride salt is the principle ingredient of many commercially available deicers. Calcium chloride melts snow and ice by its osmotic action. We present a case of skin and soft tissue necrosis associated with the use of a calcium chloride-containing deicer. Although calcium chloride is known to produce soft tissue necrosis if it extravasates during intravenous administration, necrosis and skin sloughing has rarely been described after topical exposure to this salt. Calcium chloride likely produces tissue injury from the heat liberated by mixing calcium chloride with water (exothermic reaction) and from direct calcium deposits in the skin (calcinosis cutis) and soft tissue.
ATRX contributes to epigenetic asymmetry and silencing of major satellite transcripts in the maternal genome of the mouse embryo

A striking proportion of human cleavage-stage embryos exhibit chromosome instability (CIN). Notably, until now, no experimental model has been described to determine the origin and mechanisms of complex chromosomal rearrangements. Here, we examined mouse embryos deficient for the chromatin remodeling protein ATRX to determine the cellular mechanisms activated in response to CIN. We demonstrate that ATRX is required for silencing of major satellite transcripts in the maternal genome, where it confers epigenetic asymmetry to pericentric heterochromatin during the transition to the first mitosis. This stage is also characterized by a striking kinetochore size asymmetry established by differences in CENP-C protein between the parental genomes. Loss of ATRX results in increased centromeric mitotic recombination, a high frequency of sister chromatid exchanges and double strand DNA breaks, indicating the formation of mitotic recombination break points. ATRX-deficient embryos exhibit a twofold increase in transcripts for aurora kinase B, the centromeric cohesin ESCO2, DNMT1, the ubiquitin-ligase (DZIP3) and the histone methyl transferase (EHMT1). Thus, loss of ATRX activates a pathway that integrates epigenetic modifications and DNA repair in response to chromosome breaks. These results reveal the cellular response of the cleavage-stage embryo to CIN and uncover a mechanism by which centromeric fission induces the formation of large-scale chromosomal rearrangements. Our results have important implications to determine the epigenetic origins of CIN that lead to congenital birth defects and early pregnancy loss, as well as the mechanisms involved in the oocyte to embryo transition.
Consummate solution to the problem of classical electromagnetic scattering by an ensemble of spheres. I: Linear chains.

An outline is provided of the derivation of an order-of-scattering technique that we apply here for the first reported time to the study of light scattering by two or more interacting spheres. This new method provides what is to our knowledge the first complete physical description of the classical processes involved in cooperative EM scattering by an aggregate of spheres. In addition, the algorithms that it employs are often more efficient than those used in an already established method. Comparisons between selected calculations and experimental results are made for linear chains of three and five spheres, and effects of particle orientation are investigated theoretically.
Real-space observation of molecular motion induced by femtosecond laser pulses.

Femtosecond laser irradiation is used to excite adsorbed CO molecules on a Cu(110) surface; the ensuing motion of individual molecules across the surface is characterized on a site-to-site basis by in situ scanning tunneling microscopy. Adsorbate motion both along and perpendicular to the rows of the Cu(110) surface occurs readily, in marked contrast to the behavior seen for equilibrium diffusion processes. The experimental findings for the probability and direction of the molecular motion can be understood as a manifestation of strong coupling between the adsorbates' lateral degrees of freedom and the substrate electronic excitation produced by the femtosecond laser radiation.
Estado y Desarrollo Económico

Resumen es: Hoy en dia el Consenso de Washington sobre el desarrollo esta desacreditado. La historia reciente del mundo en desarrollo ha sido poco amable con la afir...
Image Formation and Halo Removal in Diffraction Phase Microscopy with Partially Coherent Illumination

We present a quantitative model which describes the observed phase reductions and halo-effect in quantitative phase imaging systems under partial spatial coherence and provide a practical method to eliminate the halo and obtain accurate topography.
Novel Brønsted Acidic Ionic Liquids and Their Use as Dual Solvent−Catalysts

The reaction of triphenylphosphine or N-butylimidazole with cyclic sultones gives zwitterions that are subsequently converted into ionic liquids by reaction with trifluoromethane sulfonic acid or p-toluenesulfonic acid. The resulting ionic liquids have cations to which are tethered alkane sulfonic acid groups. These Bronsted acidic ionic liquids are useful solvent/catalysts for several organic reactions, including Fischer esterification, alcohol dehydrodimerization and the pinacol rearrangement. The new ionic liquids combine the low volatility and ease of separation from product normally associated with solid acid catalysts, with the higher activity and yields normally found using conventional liquid acids.
Attachment of a fluorescent label to 4-thiouracil and 4-thiouridine.

Abstract The conversion of 4-thiouracil and 4-thiouridine into fluorescent derivatives has been carried out using 4-bromomethyl-7-methoxy-2-oxo-2H-benzopyran. Adsorption of the water-insoluble reagent onto Celite allowed the reaction to be applied to completely aqueous media. The conditions employed for the reaction, pH 8.3–8.4 and 37°, are such as to allow ready extension to a tRNA. The blue-white fluorescence of the product ( λ max = 400 nm) is visible down to concentrations on the order of 10 −7 M .
Incorporation of galactose into galactosyltransferase.

Abstract Bovine skim milk galactosyltransferase (EC 2.4.1.22) retained its catalytic activity after partial enzymatic removal of sialic acid and galactose. Desialylated and degalactosylated galactosyltransferase was a galactosyl acceptor in the galactosyltransferase reaction. [ 14 C] Galactose from UDP-[ 14 C] galactose was incorporated into the carbohydrate-depleted galactosyltransferase by native galactosyltransferase. The results suggest that galactosyltransferase participates in the biosynthesis of its glycopeptides of the sialic acid-galactose- N -acetylglucosamine type.
A reflection-type oil-film skin-friction meter

Oil-film skin-friction meter for both flight and wind-tunnel applications uses internal reflection and is self-contained, compact unit. Contained in palm-sized housing, in which source of light, mirrors, and sensor mounted rigidly in alignment. Entire unit mounted rigidly under skin of aircraft or wind tunnel, eliminating any relative vibration between optical elements and skin of aircraft or wind tunnel. Meter primarily applicable to flight and wind-tunnel tests, also used in chemical-processing plants.
Monoaminergic afferents to the neocortex: a developmental histofluorescence study in normal and Reeler mouse embryos.

Summary The patterns of distribution of monoaminergic (MA) afferents during early histogenesis of the neocortex of normal and Reeler mice are studied by histtifluorescence microscopy. Fluorescing fibers appear rostrally in the cortex of both genotypes on the 14th embryonic day (E14), which is within 24 h of the development of the cortical plate. They are distributed to all regions of the cortex by the time of birth. Although the patterns of intracortical deployment differ in the two genotypes, the fibers appear to have homologous target structures. These are: (1) the polymorphic cells of the subplate in the depths of the normal and in the superplate near the surface of the mutant cortex; and (2) the zones of consolidation of apical dendrites of pyramidal cells: the external plexiform zone of normal and a series of intracortical plexiform planes in the mutant cortex. By contrast, the axons of this system do not branch significantly among the compactly ordered somata of pyramidal cells within the cortical plate of either genotype.
Use of carbon dioxide laser in improving knot security in polyester sutures.

Knot slippage continues to be a serious concern in surgery. This study explored the possibility of improving knot performance by exposing it to radiation from a CO2 laser. The specimens were mounted in a special device and exposed in a predetermined position for precisely controlled lengths of time. In the first set of experiments, the welding of ends was examined in nylon and polyester sutures. Although the welding was easily achieved, the joint was found brittle and its strength lower than that of a surgical knot. In the next set of experiments, the work was performed at a more fundamental level using oriented, high density, polyester films. The results showed that up to a certain level of exposure the tensile properties did not change, but beyond it a rapid decay took place. Shear tests on polyester sutures twisted together and then exposed to various levels of energy indicated that a bond of maximum strength developed at this exposure. Mersilene sutures of size 3/0 containing a two throw square knot when exposed to energy of this level produced optimal results. The knot strength increased by about 16% (from 13.4 N unexposed to 15.6 N exposed) and the slippage often known to occur in a two-throw knot was completely absent. This work performed under standard atmospheric conditions provided a direction for greatly enhancing the performance of a two-throw knot in terms of both the security and the strength. The investigation, however, must now be extended to other suture materials and sizes and to in vivo environments to realize the gain in actual surgery.
AFLATOXIN PRODUCTION IN SUPPLEMENTAL FEEDERS PROVIDED FOR NORTHERN BOBWHITE IN TEXAS AND OKLAHOMA

Mycotoxins are toxic metabolites produced by various species of fungi. Aflatoxin (AF), a particular type of mycotoxin, can negatively impact many wildlife species in the laboratory; however, the magnitude of the problem in the field environment is unclear. Wild birds generally consume a combination of native foods and agricultural grains. A common practice in which birds, such as northern bobwhite (Colinus virginianus), contact stored agricultural grain is through supplemental feeding. This feeding practice may promote the production of AF. The objectives of this study were to (1) examine AF production in supplemental feeders and (2) examine the relationship between weather and AF production in supplemental feeders. Samples were collected from supplemental feeders from November through February of 1996–97 and 1997–98. Mean monthly AF concentration of samples from feeders ranged from 0.57 ± 2.86 to 15.47 ± 14.69 ppb. Aflatoxin concentration in supplemental feeders increased from pre-sample to one month aft...
Strontium and calcium uptake and excretion in lactating dairy cows.

Abstract Sr 89 and Ca 45 were given orally to lactating dairy cows. From a single dose, 0.55±0.05 and 1.8±0.30% of the administered Sr 89 were found in milk and urine, respectively, during a nine-day period. Under the same conditions, 3.77±0.17 and 0.82±0.08% of the administered Ca 45 were found in milk and urine, respectively. The average observed ratios of Sr 89 /Ca 45 for four cows were: blood diet=0.33; urine diet=1.82; milk diet=0.15; milk blood=0.44, urine blood=5.43. The excretion patterns for Sr 89 in milk, urine, and feces can be described almost entirely by an exponential function of time.
Folding aggregated proteins into functionally active forms

The successful expression and purification of proteins in an active form is essential for structural and biochemical studies. With rapid advances in genome sequencing and high-throughput structural biology, an increasing number of proteins are being identified as potential drug targets but are difficult to obtain in a form suitable for structural or biochemical studies. Although prokaryotic recombinant expression systems are often used, proteins obtained in this way are typically found to be insoluble. Several experimental approaches have therefore been developed to refold these aggregated proteins into a biologically active form, often suitable for structural studies. The major refolding strategies adopt one of two approaches - chromatographic methods or refolding in free solution - and both routes have been successfully used to refold a range of proteins. Future advances are likely to involve the development of automated approaches for protein refolding and purification.
Choosing the right coronary test.

Technical advances have substantially improved the clinician’s ability to find and describe coronary disease. They also pose a bewildering array of choices.
Gonadotropin action and androgen synthesis in enzyme disperesed testicular cells of the turtle (Chrysemys picta)

Abstract Research into the evolution of gonadotropin molecules and the phylogenetic development of gonadal responses to these hormones has been hampered by the absence of a direct and quantitative test for steroidogenesis in lower vertebrates. We report here the development of a sensitive and responsive assay for gonadotropins using enzyme-dispersed testicular cells derived from a turtle ( Chrysemys picta ). Production of androgens from endogenous precursors was measured by radioimmunoassay. Cell suspensions obtained by collagenase treatment of whole testis synthesized testosterone in response to homologous and heterologous gonadotropins. All mammalian FSH's tested (ovine, rat, human) and PMS elicited dose-related increases in androgen synthesis. LH's and hCG were either ineffective or more than 100 times less potent than corresponding FSH's. Avian LH (avLH) and crude turtle pituitary (tPIT) were also active in the turtle cell system. Antibody to avLH partially neutralized responses to rat FSH, avLH, and tPIT indicating a degree of molecular correspondence among these three hormones. Although seasonal differences in gonadotropin responsiveness (maximal androgen production) were observed, it is not clear from these experiments whether Sertoli or Leydig cells are the source of secreted androgen.
AN EMPIRICAL STUDY OF STOCK PRICE AND RISK AS THEY RELATE TO ACCOUNTING CHANGES IN INVENTORY VALUATION METHODS

s of Doctoral Dissertations 1599 increased earnings obtained by giving up LIFO. When an accounting change simultaneously affects the economic value and reported income of the firm in opposite directions, the market price seems to follow the former; and in this sense the market is not "fooled" by manipulation of the information system. The assumption that the risk of firms is constant may not always hold. Changes in risk can be detected by the use of random coefficient models. The adaptive regression model can be used to estimate the behavior of an unstable risk parameter, and measure the association of price and risk of stocks with specific economic events. This content downloaded from 157.55.39.128 on Mon, 18 Jul 2016 05:50:18 UTC All use subject to http://about.jstor.org/terms
(3He, d) and (3He, t) reactions on 9Be and 11B

Abstract The reactions 9Be(3He, d)10B, 9Be(3He, t)9B, 11B(3He, d)12C and 11B(3He, t)11C were studied. Deuterons were observed leaving 10B at excitations of 0, 0.72, 1.74, 2.15, 3.59, 4.77, 5.16, 5.92, 6.16 and 6.57 MeV. (The 5.16 group probably consists of the unresolved 5.16 and 5.18 MeV states). Tritons were obserbed leaving 9B at excitations of 0 and 2.34 MeV. In addition, a typical three-body breakup continuum is seen in the triton spectra. Deuterons leaving 12C at excitations of 0, 4.43, 7.66, 9.64 and 12.71 MeV were observed. Tritons were observed leaving 11C at excitations of 0 and 2.00 MeV. Excitation functions taken in the region of 10 MeV show no strong resonance structure.
Mechanisms for Li and Be production in the 14 N + 12 C reaction

Measurements of the yields of $^{6,7}\mathrm{Li}$ and $^{7,9}\mathrm{Be}$ have been made for the $^{14}\mathrm{N}$ + $^{12}\mathrm{C}$ reaction at ${E}_{^{14}\mathrm{N}}=86.9 \mathrm{and} 157.0$ MeV. Statistical model calculations are compared with the data in order to determine the reaction mechanism. It is concluded that more than half of the total Li and Be yield at these bombarding energies arises from processes other than compound nucleus formation and the subsequent evaporation of a $^{6,7}\mathrm{Li}$ or $^{7,9}\mathrm{Be}$ nucleus. The most likely production mechanism at high bombarding energies appears to be the decay of a projectile-like fragment excited in a peripheral collision.
Puberty as a life history transition.

Background: James Tanner's landmark publication, Growth at Adolescence, was not only the first and most comprehensive treatise on the subject of human pubertal development of its time, its core insights have held up remarkably well over time. Review: This review connects Tanner's contributions to contemporary understanding of puberty as a process fundamentally driven by neuroendocrine maturation. It introduces the concepts of the ‘hour-glass of puberty’ and ‘somatic strategy’ as heuristic constructs. The ‘hour-glass of puberty’ describes the converging pathways of information flow influencing the timing of the neuroendocrine events of puberty and its ramifying consequences throughout the body. Somatic strategy refers to the pattern of sex-specific, adult body morphology that develops at puberty as the individual undergoes a life history transition from juvenile to adult.