cssi/SciSciGPT-SciSciNet huggingface dataset:
Reactions of the trimethylsilyl ion with 1,2‐cyclopentanediol isomers in the collision region of a triple quadrupole instrument

Ion-molecule reactions with the trimethylsilyl ion were used to distinguish between cis- and trans-1,2-cyclopentanediol isomers. The ion kinetic energy of [Si(CH3)3]+ was varied from 0 eV to 15 eV (center of mass frame of reference). At low ion kinetic energies (<4 eV), there are significant differences in the relative stabilities and decomposition behavior of the adduct ions [M + Si(CH3)3]+. The cis-1,2-cyclopentanediol isomer favors decomposition of [M + Si(CH3)3]+ to yield the hydrated trimethylsilyl ion [Si(CH3)3OH2]+ at m/z 91. For the trans isomer, the formation of the hydrated trimethylsilyl ion is an endothermic process with a definite threshold ion kinetic energy.
Reduction of chromium(VI) by ascorbate leads to chromium-DNA binding and DNA strand breaks in vitro

Chromium(VI) is a known human carcinogen which requires intracellular reduction for activation. Ascorbate (vitamin C) has been reported to function as a major reductant of Cr(VI) in animals and cell culture systems. The reaction of Cr(VI) with varying concentrations of ascorbate was studied under physiological conditions in vitro in order to determine the types of reactive intermediates produced and to evaluate the reactivity of these intermediates with DNA. Reactions of 1.8 mM Cr(VI) with 0-18 mM ascorbate at pH 7.0 in N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid (HEPES; 0.10 M) and tris(hydroxymethyl)aminomethane hydrochloride (Tris.HCl; 0.050 M) buffers were studied by electron paramagnetic resonance and UV/visible spectroscopy. Cr(V) and carbon-based free radical adducts of 5,5-dimethyl-1-pyrroline 1-oxide (DMPO) were observed at 0.5 to 1 and 1 to 1 reactions of ascorbate to Cr(VI). Levels of Cr(V) were higher for reactions in HEPES buffer, and levels of carbon-based radicals were higher in Tris.HCl buffer. Levels of Cr(IV) and Cr(III) increased with increasing concentration of ascorbate in both buffers. Reaction of Cr(VI) with varying ascorbate in the presence of calf thymus DNA or pBR322 DNA resulted in Cr-DNA adducts and plasmid relaxation, respectively. Maximum binding of Cr to DNA was observed for the 1:1 reaction ratio of Cr(VI) with ascorbate in both HEPES and Tris.HCl buffers, but total Cr bound to DNA was 8-fold lower in Tris.HCl than HEPES buffer. Preincubation of Cr(VI) with ascorbate before reaction with DNA decreased Cr-DNA binding to background levels. Preincubation of Cr(III) with ascorbate resulted in only low Cr-DNA binding. Levels of Cr-DNA binding were higher with single-stranded vs double-stranded DNA. Reactions with 14C-labeled ascorbate produced no cross-linking of ascorbate to DNA. Maximum plasmid relaxation was observed for the 1:1 ascorbate to Cr(VI) ratio in both buffers; however, single-strand breaks were 2-fold higher in Tris.HCl than HEPES buffer. Reactions with plasmid in the presence of DMPO quenched formation of single-strand breaks. Interpretation of these results in light of the spectroscopic studies suggested that Cr(V) and carbon-based radicals were responsible for Cr-DNA adducts and DNA single-strand breaks, respectively.
Performance comparison of whole-genome sequencing platforms

Whole-genome sequencing is becoming commonplace, but the accuracy and completeness of variant calling by the most widely used platforms from Illumina and Complete Genomics have not been reported. Here we sequenced the genome of an individual with both technologies to a high average coverage of ∼76×, and compared their performance with respect to sequence coverage and calling of single-nucleotide variants (SNVs), insertions and deletions (indels). Although 88.1% of the ∼3.7 million unique SNVs were concordant between platforms, there were tens of thousands of platform-specific calls located in genes and other genomic regions. In contrast, 26.5% of indels were concordant between platforms. Target enrichment validated 92.7% of the concordant SNVs, whereas validation by genotyping array revealed a sensitivity of 99.3%. The validation experiments also suggested that >60% of the platform-specific variants were indeed present in the genome. Our results have important implications for understanding the accuracy and completeness of the genome sequencing platforms.
Changes we can believe in

The new Republican majority in the US House of Representatives has just arrived in Washington, DC, and the phrase “change we can believe in” feels almost like a thorn. And yet, with this editorial announcing various changes to publishing policy and scope at DMM, I focus on changes in which I do
Nietzsche's Last Laugh: Ecce Homo as Satire

Nietzsche's Ecce Homo was published posthumously in 1908, eight years after his death, and has been variously described ever since as useless, mad, or merely inscrutable. Against this backdrop, Nicholas D. More provides the first complete and compelling analysis of the work, and argues that this so-called autobiography is instead a satire. This form enables Nietzsche to belittle bad philosophy by comic means, attempt reconciliation with his painful past, review and unify his disparate works, insulate himself with humor from the danger of 'looking into abysses', and establish wisdom as a special kind of 'good taste'. After showing how to read this much-maligned book, More argues that Ecce Homo presents the best example of Nietzsche making sense of his own intellectual life, and that its unique and complex parody of traditional philosophy makes a powerful case for reading Nietzsche as a philosophical satirist across his corpus.
Enhanced platelet reactivity and thrombosis in Apoe-/- mice exposed to cigarette smoke is attenuated by P2Y12 antagonism.

Introduction Smoking increases the risk of acute arterial thrombosis, including myocardial infarction, likely due to multi-factorial effects on the vasculature. Heightened platelet reactivity may be among the adverse effects of smoke exposure.
No option but to go: Poetic rationalization and the discursive production of Mexican migrant identity

Abstract This article intervenes into identity research in migration studies, showing that a semiotic–pragmatic approach makes the study of identity more ethnographically precise. Because the efficacy of linguistic signs depends on their social recognizablity, semiotic studies of identity necessarily ground processes of identification in their particular cultural milieus. I focus on locally salient theories of personhood and agency, which undergird identity in my research site (Uriangato, Mexico). In particular, I analyze how these theories are expressed through images of personhood, or social personae, produced in one woman’s articulation of a discourse genre I call “poetic rationalization,” considering the way this process is gendered. The central claim is that enduring attachments to social personae is a central way people construct migrant identities.
Gas evolution during oil shale pyrolysis. 1. Nonisothermal rate measurements

Abstract The rate of evolution of CH4, CO, CO2, H2, C2 hydrocarbons, and C3 hydrocarbons during pyrolysis of Colorado oil shale between 25 and 900 °C is reported. All experiments were performed nonisothermally using linear heating rates varying from 0.5 to 4.0 °C min−1. Hydrogen is the major noncondensable gas produced by kerogen pyrolysis. The amount of H2 released is influenced, via the shift and Boudouard reactions, by the CO2 evolved from mineral carbonates. Lesser amounts of C1, C2, and C3 hydrocarbons are produced. On the basis of heat content, however, the combined C1 to C3 hydrocarbons contribute twice as much as H2 to the heating value of the pyrolysis gas. The evolution of H2 and CH4 involves processes that are interpreted as a ‘primary’ pyrolysis of the kerogen to generate oil, and a higher temperature ‘secondary’ pyrolysis of the carbonaceous residue. The CO formed is a product of the Boudouard reaction; nearly complete conversion of the carbon residue to CO via this reaction is observed.
Approaching the Mind in Clinical Interviewing: The Techniques of Soundings and Counterprojection

When an interviewer and a patient meet, it is the meeting place of two minds. This article discusses the essential use of clinical imagination in the initial interview and presents two techniques, soundings and counterprojection that can enhance the interviewer's ability to create a shared psychologic space with the interviewee.
Topologies which generate a complete measure algebra

Topologies are constructed so that the σ-field they generate is the collection of Lebesgue-measurable sets. One such topology provides a simple proof of von Neumann's theorem on selecting representatives for bounded measurable “functions.”
Protactinium‐thorium ratio as a proxy for ocean circulation

The Atlantic meridional overturning circulation (AMOC) transports water and heat over long distances in the Atlantic Ocean and is believed to have an important effect on Earth's climate. Knowing how strong the AMOC was in the past is essential to understanding past climate. One proxy researchers have used to assess the past strength of the AMOC is the sedimentary protactinium- thorium ratio (231Pa/230Th). Both 231Pa and 230Th are produced through decay of uranium at a constant rate in the ocean water column, but230Th does not last long enough in the water to be transported away from the location where it was produced, while 231Pa has a longer residence time in the water. Therefore, sedimentary 231Pa/230Th ratios could provide information about the strength of past ocean circulation.
FOLATE AND COLONIC CARCINOGENESIS : SEARCHING FOR A MECHANISTIC UNDERSTANDING

Abstract A growing body of epidemiologic data indicates a relationship between folate status and the risk of developing colorectal neoplasia. Diminished folate status is associated with a higher risk of neoplasia. Interestingly, this phenomenon has been observed with relatively modest alterations in folate status and may even be present when vitamin status is diminished within the range of what is conventionally accepted as normal. A controlled laboratory study in an animal model of colorectal carcinogenesis confirmed a cause and effect relationship between folate deficiency and enhanced carcinogenesis. Possible means by which this effect may occur are discussed. Preliminary studies in humans with adenomatous polyps or colorectal cancers suggest that an intermediary marker of colonic tumorigenesis may be reversed by administering pharmacologic doses of folic acid, indicating a possible chemopreventive role for this vitamin.
The Kapitza thermal boundary resistance

A theory of the Kapitza thermal boundary resistance has been developed which includes not only the scattering of phonons at the interface between two different materials, but also the scattering of phonons within either material near the interface. The theory is shown to be in good agreement with present measurements on solid-solid contacts as well as with previously published low-temperature data on the contact between liquid helium and copper.
An azidoaryl thioglycoside of sialic acid. A potential photoaffinity probe of sialidases and sialic acid-binding proteins.

Abstract An azidoaryl thioglycoside of sialic acid was prepared, as a potential photoaffinity probe reagent for the analysis of sialidases and sialic acid-binding proteins, by treatment of the glycosyl chloride of N -acetylneuraminic acid methyl ester with potassium thioacetate to give, in 70% yield, methyl 5-acetamido-4,7,8,9-tetra- O -acetyl-2- S -acetyl-2,3,5-trideoxy-2-thio-α- d - glycero - d - galacto -2-nonulopyranosonate. Selective hydrolysis of the thioacetate ester, followed by condensation with 4-fluoro-3-nitrophenyl azide, O -deacetylation, and hydrolysis gave (4-azido-2-nitrophenyl)- 5-acetamido-2,3,5-trideoxy-2-thio-α- d - glycero - d - galacto -2-nonulopyranosidonic acid.
Metabolism of cytokinin: Phosphoribosylation of cytokinin bases by adenine phosphoribosyltransferase from wheat germ☆

Adenine phosphoribosyltransferase (AMP:pyrophosphate phosphoribosyltransferase EC 2.4.2.8) which catalyzes the phosphoribosylation of cytokinin bases and adenine to form the corresponding nucleotides were partially purified from the cytosol of wheat (Triticum aestivum) germ. This enzyme (molecular weight, 23,000 ± 500) phosphoribosylates the bases at an optimum Mg2+ concentration of 5 mm and optimum pH of 7.5 (50 mm Tris-HCl buffer). Km values for N6-(Δ2-isopentenyl)adenine, N6-furfuryladenine, N6-benzyladenine, and adenine are 130, 110, 154, and 74 μm, respectively, in 50 mm Tris-HCl buffer (pH 7.5) at 37 °C. Hypoxanthine and guanine are not substrates for the enzyme. In concerting with other cytokinin metabolic enzymes, this enzyme may play a significant role in maintaining the supply of adequate levels of “active cytokinin.”
A task difficulty—G stress experiment

This paper describes a study of methods to design manual tracking tasks. These tasks are to be used to help investigate performance changes as humans are subjected to G acceleration stress. The design of the tasks had to meet two criteria. First, the tasks were required to differ from one another in terms of subjective difficulty (as well as showing a performance change empirically). Secondly, each task had to be sensitive enough to show performance changes in a stress/non-stress environment. The tasks used were of a sum of sines design approach which occurs commonly in manual control theory. The type of environmental stress considered in this study was a + Gz acceleration to which aircraft pilots are exposed during flight manoeuvres. The experiment was conducted on the Dynamic Environmental Simulator (D.E.S.), a three degree of freedom human centrifuge located at the Air Force Aerospace Medical Research Laboratory at Wright Patterson Air Force Base, Ohio.
The effect of decreasing length of stay on discharge destination and readmission after coronary bypass operation

Background. Over the decade of the 1990s, hospital stay after operation declined in response to prospective payment and managed care. As a result, complications previously detected and treated in the hospital may have begun to occur after discharge. In addition, discharge to nursing homes and rehabilitation hospitals may have increased. To address these questions, we used a statewide database to look at the use of postacute care and the 30-day readmission and mortality after coronary bypass operation. Methods. A modification of the Commonwealth of Massachusetts Division of Health Care Finance and Policy discharge data to include a unique patient identifier allowed us to retrospectively track patient destination at discharge and study 30-day readmission to all hospitals in the state. Results. Over the 3-year period after the institution of the unique patient identifier (1993 to 1996), postoperative length of stay after coronary bypass operation decreased from 7.4 to 6 days (19%, P <.0005), but the 30-day readmission rate (17.7%) did not increase. Discharge to rehabilitation hospitals and skilled nursing facilities rose significantly (11.7% to 23.8%), especially in the Medicare population (17.2% to 38.5%). Mortality in the 30 days after discharge remained constant at 0.3%. Conclusions. A shorter postoperative length of stay did not appear to disadvantage coronary artery bypass patients by increasing their likelihood of readmission or death. Cost savings from reduced length of stay were offset by increased use of postacute services. (Surgery 2002;132:10-5.)
Access and Resistance to Dominant Forms of Discourse: Critical Literacy and "At Risk" High School Students

In an effort to both challenge and engage adolescent students deemed to be academically “at risk,” the purpose of this study was to examine the possibility of creating a pedagogical bridge between dominant (school sanctioned) and non-dominant (non-school) forms of literacy. The study was conducted within a setting where high school students were invited to co-construct a literacy group with two primary adult mentors: an education professor from a local state university and the school's Communities in Schools Youth Coordinator. Through an examination of student response to texts containing themes of social justice, findings for this study reveal that creating contexts where “at risk” adolescents can explore marginalized positionalities presented in a variety of genres of text creates a bridge between dominant and non-dominant forms of discourse. Implications for the role of critical literacy—taking action to foster a more just society—are presented as a key component for creating this bridge.
A case study of a frontal system simulated by a climate model: Clouds and radiation

A case study is carried out to evaluate the capability of the Community Atmosphere Model (CAM3) in simulating frontal clouds over the Southern Great Plains (SGP). It focuses on a midlatitude cyclonic storm system observed during the March 2000 Intensive Observation Period (IOP) of the Atmospheric Radiation Measurement Program (ARM). Cloud biases are found to be consistent with climate model biases in this region: overestimation of optically thick clouds and shortwave cooling at the top-of-the-atmosphere (TOA), underestimation of optically thin middle clouds. Satellite observations, NOAA ETA analysis and a suite of ARM measurements are used to analyze the model cloud biases. We found two independent causes of model errors during two stages of the evolution of the cyclone. In the first stage, the biases are from cloud microphysical properties. The model significantly overpredicted cloud liquid water path, while it underpredicted cloud ice water path. As a result, it overestimated the magnitude of shortwave cloud forcing. In the second stage, the model cloud biases are primarily caused by a faster eastward propagation of the 500 mbar ridge behind the cyclone, which dissipated the high- and middle-level clouds but favored low clouds, leading to biases in cloud forcing. Averaged over the cyclone domain and period, the model simulated shortwave and longwave TOA cloud forcing of -113 W/m 2 and 30 W/m 2 , respectively, while the corresponding observations are -69 W/m 2 and 38 W/m 2 . Our results illustrated the feasibility of using synoptic cases to understand and eventually eliminate systematic cloud biases in climate models.
Imaging the PCP site of the NMDA ion channel.

Abstract The N-methyl-D-aspartate (NMDA) ion channel plays a role in neuroprotection, neurodegeneration, long-term potentiation, memory, and cognition. It is implicated in the pathophysiology of several neurological and neuropsychiatric disorders including Parkinson's Disease, Huntington's Chorea, schizophrenia, alcoholism and stroke. The development of effective radiotracers for the study of NMDA receptors is critical for our understanding of their function, and their modulation by endogenous substances or therapeutic drugs. Since the NMDA/PCP receptor lies within the channel, it is a unique target and is theoretically accessible only when the channel is in the active and “open” state, but not when it is in the inactive or “closed” state. The physical location of the NMDA/PCP receptor not only makes it an important imaging target but also complicates the development of suitable PET and SPECT radiotracers for this site. An intimate understanding of the biochemical, pharmacological, physiological and behavioral processes associated with the NMDA ion channel is essential to develop improved imaging agents. This review outlines progress made towards the development of radiolabeled agents for PCP sites of the NMDA ion channel. In addition, the animal and pharmacological models used for in vitro and in vivo assessment of NMDA receptor targeted agents are discussed.
Why nobody should care about operating systems for exascale

Reaching the next three orders of magnitude increase in parallel computing performance poses significant new challenges for system software. The landscape of hardware for computing, memory, networking, and storage is changing, which is in turn driving the need for new parallel algorithms and programming models. Power, resiliency, massive on-node parallelism, and heterogeneity are some of the important issues that are driving the need for new and alternative approaches to the design and implementation of scalable system software for high-performance computing. However, these changes are minimizing the importance of the operating system as the lowest-level resource manager, but are rather focusing more attention on the runtime system as the key intermediary between applications and hardware. This talk will discuss some of the important capabilities needed for exascale runtime systems and offer a perspective on addressing some of the fundamental challenges and opportunities of exascale computing.
Control of flexible, kinematically redundant robot manipulators

The use of kinematic redundancy in control algorithms to avoid singularities evade obstacles minimize joint torques manipulator kinetic energy end effector contact forces etc. . . has been among the most active research topics in the field of robotics in the past few years. However these approaches have been associated mainly with rigid manipulators where there is no unpredictable flexible motions. When dealing with flexible manipulators the flexibility of the system will cause undesired inaccuracy in end effector motion. If these manipulators are kinematically redundant their kinematic redundancy can be used to compensate for the end effector motion inaccuracy and in many cases help damp out the vibrations. This paper examines this issue and introduces new control algorithms designed to regulate the flexibility while maintaining precise tracking of the end effector trajectory. The dynamic model used is a special case of the general multi-body dynamics designed to maximize its computational efficiency.
The Diffusion of State-Level Nonprofit Program Innovation: The T.E.A.C.H. Early Childhood Project

This article examines the diffusion of a state-level nonprofit program to other states across the United States. Current literature on innovation diffusion largely overlooks the diffusion of nonprofit program innovation. Although several streams of related diffusion research have considered organizational change and government policy transfer, they miss organizational and contextual factors particularly important for nonprofits. This study considers organizational and environmental factors in the transfer of state-level nonprofit program innovation using in-depth interviews with 74 policy actors to examine the spread of the T.E.A.C.H. Early Childhood Project to nonprofits in four states. It identifies similarities and differences between nonprofit program and government policy diffusion and proposes a modified framework for state-level nonprofit program diffusion that consists of multiple stages and participant roles.
Analysis of Strain Effects in Ballistic Carbon Nanotube FETs

The effect of uniaxial and torsional strain on the performance of ballistic carbon nanotube (CNT) Schottky-barrier (SB) field-effect transistors (FETs) is examined by self-consistently solving the Poisson equation and the Schroumldinger equation using the nonequilibrium Green's function formalism. A mode space approach can be used to reduce the computational cost of atomistic simulations for the strained CNTs by orders of magnitude. It is shown that even a small amount of uniaxial (< 2%) or torsional (<5deg) strain can result in a large effect on the performance of the CNTFETs due to the variation of the band gap and band-structure-limited velocity. Semiconducting CNT channels with different chiralities are influenced in drastically different ways by a certain applied strain, which is determined by a (n-m) mod 3 rule. In general, a type of strain which produces a larger band gap results in increased SB height and decreased band-structure-limited velocity, and hence a smaller minimum leakage current, smaller on current, larger maximum achievable ION/IOFF, and larger intrinsic delay. The other type of strain that reduces the band gap results in the opposite effect on the device performance metrics of the CNTFETs
H-2M3 encodes the MHC Class I molecule presenting the maternally transmitted antigen of the mouse

Abstract Mta, the maternally transmitted antigen of mice, is a hydrophobic, N-formylated mitochondrial peptide, MTF, presented on the cell surface to cytotoxic T lymphocytes by a novel major histocompatibility complex class I molecule, encoded by H-2M3 . We have cloned and sequenced two alleles of M3 , which differ in their ability to present MTF despite 99% identity in the coding regions. M3 is as divergent from classical, antigen-presenting H-2 molecules as from other class I genes of the Hmt and the Qa/Tla regions. Amino acids critical for folding of class I molecules are conserved in M3. Noncharged amino acids lining the peptide-binding groove and phenylalanine 171 may explain the unique interaction with MTF, and leucine 95 appears critical for immunological activity.
Office evaluation of incontinence and nonsurgical management options

Abstract There are many reasons why a patient may be incontinent. Often, the physician can develop a clear picture of what these may be by using history, physical examination, and simple office tests. Although it is important that a specific diagnosis be made before a patient is submitted to surgery, it is reasonable to use medical management on the basis of a presumptive diagnosis because this will allow for a relief of symptoms in the majority of patients
Mapped offset on the right-lateral Kern Canyon fault, southern Sierra Nevada, California

The north-trending Kern Canyon fault, the longest fault within the southern Sierra Nevada, has been mapped from lat 36°00′N to its northern end near lat 36°40′N. The fault cuts and offsets granitic plutons as young as 80 m.y., but despite the fact that many recent earthquake foci plot close to the fault, it does not appear to offset an overlying 3.5-m.y.-old basalt flow. Seven granitic plutons are clearly offset by the fault in a right-lateral sense. In the area mapped, offset of plutonic contacts is 6.5 to 13 km and increases southward by 0.2 km/km.
Recurring digital fibrous tumor of childhood

A case of digital fibrous tumor of childhood is described. This tumor is multicentric, of possible viral origin, and is characterized histologically by intracytoplasmic inclusion bodies within proliferating fibroblasts. The tumor recurred despite wide local excision and skin grafting.
Balancing Preservation and Logging: Public Lands Policy in British Columbia and the Western United States

Both the United States and Canada have made fundamental changes in their policies regarding natural resources. The province of British Columbia made major revisions to its forest policy in the earlyto-mid-1990s; in the western United States, policy efforts have been stymied by conflicts between state and federal officials and between conservationists and resource developers. The different structures of federalism in the two countries result in two different approaches to policymaking that are discussed here. However, the ultimate test of natural resource policy, I argue, should be their consistency with the goal of sustainable ecosystems and preservation of biodiversity. From the perspective of ecological science, neither country has been particularly successful in policymaking for public lands and for logging in particular. Both nations have failed to give priority to protecting old-growth forests and largely have rejected the idea that ancient forests are much more valuable than simply sources of timber
Fractionation of unaltered phosphatidyl (1,2-14C2) ethanol amines according to the degree of unsaturation of their predominant fatty acids.

Abstract 1. 1. Female rats were injected intraperitoneally with 1.5 μC of [ 14 C]ethanolamine (uniformly labeled) per 100 g of body weight 1 h before they were killed; and the phospholipids were separated by thin-layer chromatography, and the radioactivity of the fractions determined. 2. 2. Phosphatidyl ethanolamine, isolated by thin-layer chromatography, was fractionated according to the degree of unsaturation on AgNO 3 -treated silica gel H layers (thin-layer chromatography) into fractions containing dienes, tetraenes and hexaenes (mostly 22:6 with smaller amounts of the 22:5 fatty acids). The phosphatidyl ethanolamine was eluted with choline chloride in methanol and extracted into light petroleum. The radioactivity and fatty acids were determined, and the yields of each were 75 % or greater. 3. 3. The specific activities of the fractions varied greatly. The dienes had the highest specific activity with the tetraenes having the lowest activity. 4. 4. Hydrolysis of the phosphatidyl ethanolamine with phospholipase A, showed that in addition to palmitic and stearic acids, the α-position contained 68% of the oleic acid and about 9 % of the arachidonic acid. 5. 5. The relative simplicity of the procedure makes it a useful method for studying the metabolism of the major species of phosphatidyl ethanolamine in vivo .
On noncooperative hybrid stochastic games

Abstract The present article models and analyzes a noncooperative hybrid stochastic game of two players. The main phase (prime hybrid mode) of the game is preceded by “unprovoked” hostile actions by one of the players (during antecedent hybrid mode) that at some time transforms into a large scale conflict between two players. The game lasts until one of the players gets ruined. The latter occurs when the cumulative damage to the losing player exceeds a fixed threshold. Both hybrid modes are formalized by marked point stochastic processes and the theory of fluctuations is utilized as one of the chief techniques to arrive at a closed form functional describing the status of both players at the ruin time.
Retinoids and acne

Retinoids, chemicals that have vitamin A activity, have become important therapeutic agents for a variety of cutaneous disorders, including acne. This paper reviews the history of retinoid use in acne, including retinol, topical tretinoin, topical and systemic isotretinoin, systemic etretinate, and new investigational retinoid molecules.
Electron Kinetics in Nonpolar Liquids — Energy and Pressure Effects

Just as electron mobilities differ for liquids that are otherwise similar in bulk properties, the rates of electron reactions often change by orders of magnitude from one nonpolar liquid to another. Both positive and negative activation energies are observed and, as shown recently, application of high pressure has large effects on electron kinetics (Munoz et al., 1987; Nishikawa et al., 1988). Clearly it is a challenge to fully understand this diversity of behavior, and a comprehensive theory to account for electron reactions is needed.
An examination of the forces that generate a style

Abstract The concept of style has long been central to both historical analysis and pedagogical discourse in architecture. Most often these discussions focus on the nature of ‘signature’ physical features, but notions expressed in this article would contend that several aspects of the design process are just as significant in defining a style as the replication of features. Aspects emerging in the personal design process include operations of cognitive mechanisms, utilization of repeated procedures, personal preference for certain images, and manipulation of certain seasoned design knowledge. Employment of these factors and procedures in a design process is actually the driving force that generates recognizable features to be manifest in a style.
High field poling of electrooptic etalon modulators on CMOS integrated circuits

Reflection etalon modulators with electrooptic polymer layers as the spacer have been fabricated on the surface of a CMOS chip and successfully poled under a dc electric field at 80 V//spl mu/m. This is the first demonstration that such etalons can be fabricated on finished VLSI circuits and poled successfully without damage to the electronics while connected to the underlying circuitry. Such modulators, fabricated on the surface of integrated circuits, have potential applications in areas such as optical communication and free-space interconnects for multiprocessors. >
Crown-Down Tip Design and Shaping

The shaping affects of three types of stainless-steel files that differ only in tip shape were studied using curved canals in acrylic blocks. Ninety curved canals were divided by degree of curvature into three equal groups of 30. The canals in each group were shaped using a crown-down technique and files possessing one of the three different tip shapes. The tip shapes were biconical tip (Flex-R), conical tip (Mor-Flex), and pyramidal tip (Flex-O). The canals were photographed before and after shaping and the finished shape analyzed. The incidences of transportation, ledging, and instrument damage were recorded during instrumentation. National Institutes of Health image software was used to measure the longitudinal cross-sectional areas and cross-sectional diameters at specified canal depths. Statistical analysis showed a significant difference in the preparations between the three tip shapes. Biconical tip files (Flex-R) produced the least transportation and no ledges. Pyramidal tip files (Flex-O) produced the most transportation, ledges, and damaged files. Only pyramidal-shaped tips developed ledges and experienced file separation. The participants reported less difficulty shaping with a biconical-tipped file and the greatest technical difficulty with a pyramidal-shaped tip. This study suggests that during crown-down rotational instrumentation, biconical file tips maintain the original canal curvature better and more frequently than do conical and pyramidal file tips.
Immune hypersensitivity in the channel catfish, Ictalurus punctatus (Rafinesque)

Channel catfish, Ictalurus punctatus, exhibited passive cutaneous anaphylaxis (PCA) when sensitized with Flexibacter columnaris antiserum produced in channel catfish (the first record of PCA in any fish), but not when sensitized with homologous antiserum against channel catfish virus. Channel catfish did not give delayed skin hypersensitivity responses after immunization with either channel catfish virus or F. columnaris.
Brief postnatal PBDE exposure alters learning and the cholinergic modulation of attention in rats.

Polybrominated diphenyl ethers (PBDEs), chemicals commonly used as flame retardants, are ubiquitous in the environment and bioaccumulate in humans and wildlife. However, little is known about their potential toxicological properties. In the present study, male Long-Evans rats orally administered the commercial PBDE mixture DE-71 or corn oil for 1 week, beginning at postnatal day (PND) 6, were tested on a visual discrimination task and two sustained attention tasks. After completion of these tasks, the rats were administered a drug challenge with the muscarinic antagonist scopolamine (0, 0.01, 0.03, 0.05 mg/kg), which was injected subcutaneously 30 min prior to testing on the second sustained attention task. The DE-71‐exposed rats demonstrated deficits in learning but not in sustained attention when compared to controls. Scopolamine impaired the animals’ ability to detect the brief visual cues in controls, as evidenced by decreases in accuracy and increases in omission errors. However, the DE-71‐exposed rats were subsensitive to the effects of scopolamine on omission errors, particularly on trials in which a long delay preceded the cue, suggesting alterations in the cholinergic modulation of sustained attention. For the DE-71‐exposed rats, the lack of sustained attention deficits in the absence of the drug, coupled with the subsensitivity to scopolamine’s effects on sustained attention, suggest that although this PBDE mixture produced lasting alterations in cholinergic functioning, either (1) these alterations were not of sufficient magnitude to be behaviorally relevant, or (2) behavioral deficits resulting from these alterations were overcome by the development of compensatory neural mechanisms or response strategies in adulthood.
Pharmacodynamics of RP 59500 (quinupristin-dalfopristin) administered by intermittent versus continuous infusion against Staphylococcus aureus-infected fibrin-platelet clots in an in vitro infection model.

Model experiments were run in duplicate over 72 h. Two FPCs were removed from each model at 0, 12, 24, 36, 48, and 72 h, and the bacterial densities (in CFU per gram) were determined and compared to those of growth control experiments. Additional samples were also removed from the model over the 72-h period for pharmacokinetic evaluation. All regimens significantly (P < 0.01) decreased bacterial densities in the infected FPCs for both isolates compared to growth controls. This occurred even though MBCs were equal to or greater than the RP 59500 concentrations achieved in the models. There were no significant differences found between the dosing frequencies and levels of killing when examining each isolate separately. However, examination of the residual bacterial densities (CFU per gram at 72 h) and visual inspection of the overall killing effect (killing curve plots over 72 h) clearly demonstrated a more favorable bactericidal activity against 1199 than against the AW7 isolate. This was most apparent when the q8h and the q12h AW7 regimens were compared to all 1199 treatment regimens by measuring the 72-h bacterial densities (P < 0.01). Killing (99.9%) was not achieved against the AW7 isolate. However, a 99.9% kill was demonstrated for all dosing regimens against the 1199 isolate. The area under the concentration-time curve from 0 to 24 h was found to be significantly correlated with reduction in bacterial density for the AW7 isolate (r 5 0.74, P 5 0.04). No resistance was detected during any experiment for either isolate. RP 59500 efficacy against constitutively erythromycin- and methicillinresistant S. aureus may be improved by increasing organism exposure to RP 59500 as a function of dosing frequency.
Solar cell and array technology development for NASA solar electric propulsion missions

NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. This paper will summarize NASA's plans for high power SEP missions, initial mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.
Tongue volume and the mandibular dentition

Abstract A method utilizing the principle of fluid displacement was devised to measure the volume of the anterior portion of the tongue. A sample of thirty-nine men was used to test the relationships between measurable tongue volume, tongue length, certain angular cephalometric measurements, and lower arch dimensions. Seventeen subjects showing scalloping of the lateral borders of the tongue were compared with the main sample. Conclusions from this investigation are as follows: 1. 1. The volume of the anterior portion of the tongue can be measured with an average accuracy of 2.3 c.c. ± 1.4 c.c., using the instrument described here. 2. 2. In this sample, and with this method of measurement, the volume and length of the tongue seem to have little, if any, influence on the width and length of the lower dental arch, on the degree of interincisal relationship, and on the angle of the lower incisor teeth to the mandibular plane. 3. 3. A statistically significant correlation of 0.4 exists between measurable tongue volume and arch perimeter. 4. 4. Scalloping of the tongue does not appear to be an indication of a large tongue.
Visual representation of database queries using structural similarity

It is often useful to get high-level views of datasets in order to identify areas of interest worthy of further exploration. In relational databases, the high-level view can be described using entity-relationship diagrams, which identify relationships between entities in the data model. Such high-level views are useful for database design activities, and can be used to generate user interfaces for constructing queries. This research introduces techniques for visualizing structural similarity of database queries. We demonstrate that individual queries can be visualized using graph visualization techniques. A distance measure based on query structure is proposed that provides database designers and administrators with a high-level perspective of relationships in the underlying data.
A dissipative anisotropic fluid model for non-colloidal particle dispersions

This article examines a reduced form of the 'purely dissipative' model proposed several years ago as a general continuum model for the rheology of non-colloidal particle dispersions, ranging from Stokesian suspensions to non-cohesive granular media. Essential to the model is a positive-definite viscosity tensor η, depending on the history of deformation and providing a crucial restriction on related models for anisotropic fluids and suspensions. In the present treatment, η is assumed to be as an isotropic function of a history-dependent second-rank 'texture' or 'fabric' tensor A. A formula for η (A) borrowed from the analogous theory of linear elasticity, and its subsequent expansion for weak anisotropy provides an explicit expression for the stress tensor in terms of fabric, strain-rate and eight material constants. Detailed consideration is given to the special case of Stokesian suspensions, which represent an intriguing subset of memory materials without characteristic time. For this idealized fluid one finds linear dependence of all stresses, including viscometric normal stress, on present deformation rate, with the provision for an arbitrary fabric evolution ('thixotropy') in unsteady deformations. As a concrete example, a co-rotational memory integral is adopted for A in terms of strain-rate history, and a memory kernel with two-mode exponential relaxation gives close agreement with the rather sparse experimental data on transient shear experiments. In the proposed model, an extremely rapid mode of relaxation is required to mimic the incomplete reversal of stress observed in experiments involving abrupt reversal of steady shearing, supporting the conclusion of others that non-hydrodynamic effects, with breaking of Stokesian symmetry, may be implicated in such experiments. Qualitative comparisons are made to a closely related model, derived from a micro-mechanical analysis of Stokesian suspensions, but also involving non-Stokesian effects. The present analysis may point the way to improved micro-mechanical analysis and to further experiments. Possible extensions of the model to the viscoplasticity of dry and liquid-saturated granular media also are discussed briefly.
Maternal reflective functioning, mother-infant affective communication, and infant attachment: exploring the link between mental states and observed caregiving behavior in the intergenerational transmission of attachment.

Abstract This study examines the link between mental representations and maternal behavior within the intergenerational transmission of attachment. Maternal reflective functioning was hypothesized to predict the quality of mother – infant affective communication based on the AMBIANCE measure. Each of these measures was also considered as a predictor of the quality of infant attachment. The subjects were 45 mothers and their 10 – 14-month-old infants. Results supported each of the study's major hypotheses. The AMBIANCE measure and the reflective functioning measure had a strong negative correlation. Thus, the level of disruption in mother – infant affective communication was inversely related to the level of maternal reflective functioning. The AMBIANCE measure was also shown to be a very good predictor of infant attachment. Mothers with high AMBIANCE scores were more likely to have infants classified as disorganized or resistant, whereas mothers with low AMBIANCE scores were more likely to have infants cl...
Schema Theory Revisited

During the 1970s, schema theory gained prominence as reading researchers took up early work by cognitive scientists to explore the role of schemas in reading. In the 1980s and ’90s, the field shifted as researchers increasingly used sociocultural theories, particularly the work of L. S. Vygotsky, to frame investigations of literacy. This article provides a brief review of schema theory as situated in literacy studies. The authors review various conceptions of schema theory to consider how recent social and cultural perspectives might prompt reconsideration of schemas as transactional and embodied constructs. Concomitantly, they explore how earlier conceptions of schema theory may assist researchers in their articulation of concepts such as ideal and material tools and the role of activity in Vygotsky’s work. The article concludes with considerations of implications for future work.
Declarative Querying for Biological Sequences

The ongoing revolution in life sciences research is producing vast amounts of genetic and proteomic sequence data. Scientists want to pose increasingly complex queries on this data, but current methods for querying biological sequences are primitive and largely procedural. This limits the ease with which complex queries can be posed, and often results in very inefficient query plans. There is a growing and urgent need for declarative and efficient methods for querying biological sequence data. In this paper, we introduce a system called Periscope/SQ which addresses this need. Queries in our system are based on a well-defined extension of relational algebra. We introduce new physical operators and support for novel indexes in the database. As part of the optimization framework, we describe a new technique for selectivity estimation of string pattern matching predicates that is more accurate than previous methods. We also describe a simple, yet highly effective algorithm to optimize sequence queries. Finally, using a real-world application in eye genetics, we show how Periscope/SQ can be used to achieve a speedup of two orders of magnitude over existing procedural methods!
In situ measurements of BrO in the Arctic stratosphere

Mixing ratios of BrO have been measured in the Arctic lower statosphere with an instrument mounted on the NASA ER-2 aircraft. Observations from fourteen flights above the Arctic Circle in January and February of 1989 defined mixing ratios within the vortex of 4 + or - 2 parts per trillion by volume (pptv) at a potential temperature of 400 K, rising to 8 + or - 2 pptv at 470 K. These values are twice as large as values found at equivalent potential temperatures at lower latitudes, and are comparable to the mixing ratios found inside the antarctic polar vortex. Within the statistical uncertainty of the measurements, no BrO was observed in darkness at any time either inside or outside of the vortex, indicating that active bromine was sequestered in long-lived reservoirs, probably BrONO2 and BrCl. These measurements, in conjuction with measurements of ClO, demonstrate that the interaction of bromine and chlorine could represent a major sink for ozone in the presence of sunlight.