cssi/SciSciGPT-SciSciNet huggingface dataset:
Computational Fluid Dynamics Analysis for the Orbiter Lh2 Feedline Flowliner

In phase II, additional inducer rotations are simulated in order to understand the root cause of the flowliner crack problem. CFD results confirmed that there is a strong unsteady interaction between the backflow regions caused by the LPFTP inducer and secondary flow regions in the bellows cavity through the flowliner slots. It is observed that the swirl on the duct side of the downstream flowliner is stronger than on the duct side of the upstream flowliner. Due to this swirl, there are more significant unsteady flow interactions through the downstream slots than those observed in the upstream slots. Averaged values of the local velocity at the slots were provided to the NESC-ITA flow physics acoustics team to guide them in designing the acoustics experiment. A parametric study was performed to compare the flow field in the flowliner area when one upstream slot and one corresponding downstream slot were enlarged. No significant differences were observed between the flow field obtained from the enlarged slot configuration when compared with the original configuration. More cases must be analyzed with various enlarged slot configurations to generalize this observation. The flow through the A1 test stand and the flow through the orbiter fuel feedline manifold were simulated without the LPFTP. It was observed that incoming flow to the flowliner and inducer was more uniform in the A1 test stand then in the orbiter manifold. Additionally, each engine LPFTP in the orbiter receives significantly different velocity distributions. Because of the differences observed in the computed results, it is not possible for the A1 test stand to represent the three different engine feedlines simultaneously.
How are we doing?: tracking country image in the information age (NSF #306803)

The study proposed here is the result of work conducted under NSF Digital Government Grant #306803, "How are we doing? Tracking country image in the information age." The goal of the one-year planning grant (awarded May 2003) was to conduct project start-up activities. The objective of the study is to examine the institutional factors that influence the use of IT for knowledge management in public diplomacy. Specifically, we will examine the extent to which a knowledge management system (KMS) can aid U.S. public diplomacy officials by facilitating the public image-tracking process. To that end, we will develop and test a prototype KMS web portal designed to help public diplomacy officials gather, organize, search, and analyze image information. The two-year study will address such research questions as, what are the institutional impediments to the effective use of KMS to support image-tracking activities, and how can government agencies overcome these impediments to effectively use KMS for public diplomacy? We will partner with the U.S. Embassy in Bolivia.
Effects of Anaphoric Dependencies and Semantic Representations on Pronoun Interpretation

We describe three experiments that use priming methodology to investigate the nature of the abstract mental representations activated during pronoun resolution, in order to contribute to our understanding of how structural representations and semantic coherence representations influence pronoun interpretation. The results of Experiment 1 suggest that there exists a level of abstract anaphoric dependency representations. Experiments 2 and 3 indicate that general coherence representations are activated during pronoun interpretation and thus provide direct evidence for the existence of shared abstract representations between (non-pronominal) coherence-related inferencing and pronoun resolution processes. Moreover, Experiment 3 has implications for our understanding of the connections between linguistic and non-linguistic cognitive processes.
Aufbau und Abbau von Deckschichten (Kupfer in Salzsäure)

Es wird die Bildung und der Abbau von CuCl-Deckschichten auf Kupfer in Salzsaure untersucht. Das Strom-Zeit-Verhalten stimmt bei „geschutzten'' Elektroden quantitativ mit der Theorie von W. J. Muller uberein. Das Verhalten von Kupfer in Salzsaure wird mit dem von Eisen in Schwefelsaure verglichen, und es werden Hinweise fur weitere Untersuchungen gegeben, die zur Klarung des Passivitatsproblems an solchen Systemen durchgefuhrt werden sollten. The formation and reduction of CuCl layers on copper in hydrochloric acid has been investigated. The current-time behavior, in case of „protected electrodes'', agrees quantitatively with the theory of W. J. Muller. The behavior of copper in hydrochloric acid has been compared with that of iron in sulfuric acid and suggestions for further investigations are made, which should be carried out for clarification of the passivity-problem in such systems.
Rate-optimal fully-static multiprocessor scheduling of data-flow signal processing programs

The authors introduce the notion of a perfect-rate data-flow program and show that these programs can always be executed in minimum time without requiring any unfolding or retiming operation at all. They show that unfolding any data-flow program beyond a certain factor does not lead to any further reduction in the execution time. This optimum unfolding factor is given by the least common multiple of the loop delay counts in the data-flow program graph. The authors show that unfolding with optimum unfolding factor reduces any iterative data-flow program to an equivalent perfect-rate data-flow program. They obtain upper bounds on the number of needed processors needed to achieve minimum-time schedules. >
Sklavinios y adjetivos étnicos: una clarificación

It has been recently claimed that the first reference to Sklavinia as a territory inhabited primarily by Slavs is to be found in Theophanes Confessor. A particular passage in Theophylact Simocatta in which the word appears has been supposedly mistranslated. In reality, the passage in question contains a reference to Sklavinia at least 150 years older than the Chronographia of Theophanes.
Composition and structure of macrozooplankton and micronekton communities in the vicinity of free-drifting Antarctic icebergs

Abstract Recent warming in the Antarctic has led to increased production of icebergs; however, the ecological effects of icebergs on pelagic communities within the Southern Ocean have not been well-studied. We used a 10 m 2 MOCNESS to collect macrozooplankton and micronekton in the upper 300 m of the water column near free-drifting icebergs in the Atlantic sector of the Southern Ocean during three seasons: December 2005 (late spring), June 2008 (late fall) and March-April 2009 (late summer). Communities were dominated in all three seasons by Antarctic krill ( Euphausia superba ) and salps ( Salpa thompsoni ), which collectively comprised 60-95% of the community wet biomass in most cases. During our spring and summer cruises, mean biomass was elevated by 3.1-4.3x at a distance of 0.37 km from large icebergs vs . 9.26 km away. These differences were not statistically significant, and no trend in biomass with distance was apparent in samples from fall 2008, when total biomass was an order of magnitude lower. Biomass levels near icebergs during Dec 2005 and Mar-Apr 2009 were comparable to values reported from marginal ice zones, suggesting that waters around icebergs support macrozooplankton and micronekton communities comparable in magnitude to those in some of the most productive areas of the Southern Ocean. Sample variance also was significantly higher within 1.85 km of icebergs during Dec 2005 and Mar-Apr 2009, reflecting increased patchiness on scales sampled by the MOCNESS (20–40×10 3 m 3 filtered per sample). This pattern was not significant during Jun 2008. Large predatory medusae were observed within 1.85 km of icebergs and in Iceberg Alley, an area through which icebergs pass frequently, but were virtually absent in areas remote from icebergs. Small euphausiids showed an inverse distribution, with low densities in areas populated by large medusae. A shift in community composition from a near-iceberg assemblage dominated by herbivores to a carnivore-dominated community in Iceberg Alley may reflect a transition from bottom-up to top-down control with increasing distance and time. Body sizes of dominant species varied seasonally but did not show consistent trends with distance from icebergs. Concentrations of photosynthetic pigments in the guts of E. superba and S. thompsoni corresponded broadly to patterns in surface chlorophyll a concentrations and were comparable to maximum gut pigment concentrations measured in animals collected from highly productive marginal ice zones. Our results suggest that the macrozooplankton and micronekton assemblages near free-drifting icebergs can be quantitatively and qualitatively different from those in surrounding, iceberg-free waters, perhaps due to both bottom-up and top-down processes as well as physical forcing by the passage of a large object through the upper ocean.
Increased maternal microchimerism after open fetal surgery

Maternal-fetal cellular trafficking (MFCT) during pregnancy leads to the presence of maternal cells in the fetus and of fetal cells in the mother. Since this process may be altered in cases of pregnancy complications, we asked whether open fetal surgery leads to changes in microchimerism levels. We analyzed maternal and fetal microchimerism in fetuses who underwent open fetal surgery for repair of spina bifida and compared their levels to patients who had postnatal repair and to healthy controls. We found that maternal microchimerism levels were increased in patients who had open fetal surgery compared with controls. In contrast, patients who had fetal intervention at the time of delivery did not demonstrate increased microchimerism. These results suggest that open fetal surgery may alter trafficking. Given the importance of MFCT in maternal-fetal tolerance, we discuss potential implications for the field of preterm labor and transplantation tolerance.
Energy Accumulation and Emanation at Low Latitudes. Part III: Forward and Backward Accumulation

Abstract Short equatorially trapped Rossby waves are usually thought to he trapped and dissipated nea the region of creation because of their relatively slow group speeds and because of the relatively low amplitude basic state within which they reside. Only long Rossby waves, with stronger group speeds, are assumed to move far away from the forcing area producing remote effects or teleconnections. These restrictions on the regions of influence of Rossby waves are only valid in a motionless basic state or in a basic state that is constant with longitude. If the basic state changes in the zonal direction, even short waves have considerable remote effects. Using ray-tracing techniques and nonlinear numerical models, the impact of a zonally varying basic state on the characteristics of equatorial modes is investigated. The original low-latitude energy accumulation zone theory of Webster and Chang is extended to include the complete family of tropical waves. In equatorial regions, the majority of Rossby waves ...
Analysis of Transference Number Measurements Based on the Potentiostatic Polarization of Solid Polymer Electrolytes

Various methods developed to measure the lithium ion transference number in solid polymer electrolytes have given widely varying results. This may be explained by invalid assumptions made in the analyses of the transport experiments, such as the assumption of an ideal, dilute solution. One popular method, referred to as the steady-state current method, and based on the potentiostatic polarization of a symmetric cell, is analyzed here for a binary electrolyte under concentrated solution theory. The ratio of steady state to initial currents after the imposition of a potential step is /shown to involve all the transport properties as well as the mean molar activity coefficient of the salt. This method is compared to other methods that utilize the current/voltage response of a symmetric cell, and underlying similarities in the methods are revealed. Solid polymer electrolytes are used in electrochemical devices for batteries and fuel cells to industrial electrolysis cells.
Electron Microscopy of Living Insects

Electron micrographs of living specimens of the various developmental stages of the insect Tribolium confusum have been obtained with a scanning electron microscope. In most cases the specimens resumed their normal activity after being examined with the electron microscope and under went metamorphosis into the next stage.
Studies on the Presence of Adenosine Cyclic 3′:5′-Monophosphate in Oat Coleoptiles

The incorporation of adenosine-8-(14)C into adenosine cyclic 3':5'-monophosphate in coleoptile-first leaf segments of Avena sativa L. was investigated. Homogenates of segments incubated in adenosine-8-(14)C for either 4 or 10 hours were partially purified by thin layer chromatography followed by paper electrophoresis. A radioactive fraction, less than 0.06% of the (14)C present in the original homogenate, migrated as adenosine cyclic 3':5'-monophosphate during electrophoresis. Upon treatment with cyclic nucleotide phosphodiesterase, however, less than 10% of this radioactive fraction appeared as 5'-AMP. Deamination with NaNO(2) as well as further chromatographical purification also suggested that only a small fraction of the (14)C in the partially purified samples could be in adenosine cyclic 3':5'-monophosphate. The data suggest that levels of this nucleotide can probably be no greater than 7 to 11 picomoles per gram of fresh weight in oat coleoptiles. Treatment of such coleoptiles with physiologically active concentrations of indoleacetic acid, furthermore, had no significant effect on the (14)C radioactivity in marker adenosine cyclic 3':5'-monophosphate-containing fractions at any stage of purification during several experiments.In a single experiment, no labeled guanosine cyclic 3':5'-monophosphate could be detected in oat coleoptile-first leaf segments incubated in guanosine-8-(14)C either with or without indoleacetic acid. These results do not support the hypothesis that a cyclic nucleotide mediates the action of indoleacetic acid on oat coleoptile extension.
Uptake of luteinizing hormone by the preovulatory monkey follicle in vivo.

The concentration of LH in the follicular fluid of the rhesus monkey during the late follicular phase of the menstrual cycle was measured using a radioreceptor assay (RRA) and a heterologous ovine: antiovine RIA. During the late follicular phase of the cycle there was no significant correlation between the concentration of LH in the follicular fluid and the size of the follicle. The concentration of radioimmunoassayable LH present in follicular fluid during the ascending portion of the LH surge was directly proportional to the concentration of LH in the serum. In contrast, using RRA, the concentration of LH in follicular fluid was relatively constant in spite of a rise in serum LH. These results suggested that radioreceptor-assayable LH may bind to receptors of the follicle during the rise in serum LH during the ascending portion of the midcycle gonadotropin surge. Additional evidence for uptake of LH into the ovary was obtained by examining the difference in LH concentration in peripheral venous blood (P...
Fetal MRI-calculated total lung volumes in the prediction of short-term outcome in giant omphalocele: preliminary findings.

Objective To determine the value of fetal MRI-calculated total lung volumes (TLV) in the prediction of short-term outcome in patients with giant omphalocele (GO). Material and methods We reviewed all cases of GO undergoing fetal MRI after 21 weeks' gestation and receiving postnatal care at our institution between 2003 and 2010. Observed/expected (O/E) TLV was calculated using age-matched TLV normograms [Radiology 2001;219:236-241]. Postnatal outcomes were stratified based on O/E TLV above or below 50% of expected. Results Seventeen GO cases fulfilled the entry criteria. The mean age at fetal MRI evaluation was 25.8 ± 4.8 weeks' gestation. The mean GO TLV (21.0 ± 13.2) was lower than age-matched population norms (p Conclusion In the assessment of GO fetuses, MRI-based O/E TLV of
Mapping the λ Integrase bridges in the nucleoprotein Holliday junction intermediates of viral integrative and excisive recombination

The site-specific recombinase encoded by bacteriophage λ [λ Integrase (Int)] is responsible for integrating and excising the viral chromosome into and out of the chromosome of its Escherichia coli host. In contrast to the other well-studied and highly exploited tyrosine recombinase family members, such as Cre and Flp, Int carries out a reaction that is highly directional, tightly regulated, and depends on an ensemble of accessory DNA bending proteins acting on 240 bp of DNA encoding 16 protein binding sites. This additional complexity enables two pathways, integrative and excisive recombination, whose opposite, and effectively irreversible, directions are dictated by different physiological and environmental signals. Int recombinase is a heterobivalent DNA binding protein that binds via its small amino-terminal domain to high affinity arm-type DNA sites and via its large, compound carboxyl-terminal domain to core-type DNA sites, where DNA cleavage and ligation are executed. Each of the four Int protomers, within a multiprotein 400-kDa recombinogenic complex, is thought to bind and, with the aid of DNA bending proteins, bridge one arm- and one core-type DNA site. Despite a wealth of genetic, biochemical, and functional information generated by many laboratories over the last 50 y, it has not been possible to decipher the patterns of Int bridges, an essential step in understanding the architectures responsible for regulated directionality of recombination. We used site-directed chemical cross-linking of Int in trapped Holliday junction recombination intermediates and recombination reactions with chimeric recombinases, to identify the unique and monogamous patterns of Int bridges for integrative and excisive recombination.
Ultralow-threshold 850-nm oxide-apertured vertical-cavity lasers using AlInGaAs/AlGaAs strained active layers

Recently 850-nm wavelength has been established as the standard for local area interconnects and data-link modules using GaAs/AlGaAs vertical cavity lasers (VCLs) have become commercially available. However, the lowest threshold current (Ith) up-to-date has been obtained from 980-nm VCLs using strained InGaAs quantum wells. In this presentation we report an ultralow CW, room temperature Ith of 156 (mu) A from a 2.8 micrometers diameter VCL with three AlInGaAs quantum wells in the active region. The AlInGaAs/AlGaAs quantum well active region is used to achieve laser emission near 850 nm while maintaining the benefits of strain in lasers. Previous studies have shown that strained AlInGaAs/AlGaAs in-plane lasers exhibit the same suppression to the propagation of dark-line defects as strained InGaAs lasers. Here we have performed a preliminary burn-in study on our devices to study the reliability in AlInGaAs. AlGaAs VCLs for the first time. We found that devices showed no degradation in either output power or threshold current after 30 hours of on-wafer testing at a constant current density of 22 kA/cm2 and junction temperature of 140 degrees C. We also measured devices at various stage temperatures and found that the lowest Ith, 110 (mu) A for the 2.8 micrometers diameter VCL, occurs near 230 Kelvin, where the quantum well gain peak and the cavity mode are aligned. In addition, we examined the behavior of the external differential efficiency as a function of device size and found that due to a thicker oxide aperture than intended, optical scattering losses start to dominate for devices smaller than 4 micrometers diameter.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Characterization of self-stimulation neurons by their local potential summation properties.

Abstract Current threshold methods are used to behaviorally measure local potential summation (LPS) properties in the directly stimulated neurons mediating brain stimulation reward. Trains of paired pulses were presented at intrapair intervals of 50 to 800 μsec to rats bar pressing for brain stimulation. Current threshold excitability estimates were taken using 1) cathodal pulses, or 2) using one anodal and one cathodal pulse in each pair. The estimated decay of LPS was smooth and rapid in all animals, i.e., had a half-life less than 100 μsec. Method 2) allowed us to separate the contributions of LPS and refractory periods to these measures. Using one anodal pulse in each pair, refractory period contributions are reversed with a reversal point near 400 μsec.
Evaluation of Air Recirculation for Falling Particle Receivers.

This paper presents simulations and designs of a prototype falling particle solar receiver with air recirculation as a means of mitigating heat loss and impacts of external wind on particle flow. The flow and dispersion of different sizes of ceramic proppant (CARBO HSP) particles (1 mm, 100 μm, and 10 μm) were simulated in recirculating air flows without heating effects. Particles on the order of 0.1–1 mm yielded desirable simulated flow patterns when falling through the cavity receiver with an air-injection velocity of 3 m/s. Simulations of smaller particles on the order of 10 microns yielded unstable flow patterns that may lead to large losses of particles through the aperture. A prototype cavity receiver with air recirculation was designed and fabricated to validate the unheated simulations. The blower nozzles and suction plenum were engineered to yield the most uniform flow pattern along the entire width of the aperture. Observed and simulated air velocity distributions around the aperture and particle flow patterns using CARBO HSP particles with an average diameter of ∼0.7 mm were found to be qualitatively similar.Copyright © 2013 by ASME
Bird song learning in an eavesdropping context

Bird song learning is a major model system for the study of learning with many parallels to human language development. In this experiment we examined a critical but poorly understood aspect of song learning: its social context. We compared how much young song sparrows, Melospiza melodia, learned from two kinds of adult ‘song tutors’: one with whom the subject interacted vocally, and one whom the subject only overheard singing with another young bird. We found that although subjects learned from both song models, they learned more than twice as many songs from the overheard tutor. These results provide the first evidence that young birds choose their songs by eavesdropping on interactions, and in some cases may learn more by eavesdropping than by direct interaction.
The Structural Effects of Endogenous and Exogenous Ca2+/Calmodulin on Phosphorylase Kinase

Abstract The activity of phosphorylase bkinase (PbK) is stimulated by Ca2+ ions, which act through its endogenous calmodulin subunit (δ), and further stimulated by the Ca2+-dependent binding of exogenous calmodulin (δ′). In contrast to their highly characterized effects on activity, little is known regarding the structural effects on the (αβγδ)4 PbK holoenzyme induced by Ca2+and δ′/Ca2+. We have used mono- and bifunctional chemical modifiers as conformational probes to compare how the two effectors influence the structure of the catalytic γ subunit and the interactions among all of the subunits. As determined by reductive methylation and carboxymethylation, Ca2+ increased the accessibility of the γ subunit; it also increased the formation by phenylenedimaleimide of an αγγ conjugate that is characteristic of activated conformations of PbK (Nadeau, O. W., Sacks, D. M., and Carlson, G. M. (1997) J. Biol. Chem. 272, 26196–26201); however, Ca2+ also had structural effects that were clearly distinct from other activators. Moreover, similar structural effects of Ca2+ were observed with PbK that had been activated by phosphorylation, consistent with the fact that such activation does not eliminate the catalytic dependence of the enzyme on Ca2+. Our results suggest tiers of conformational transitions in the activation of PbK, with the most fundamental being induced by Ca2+. Analysis of the various cross-linked conjugates formed in the presence of Ca2+ byo-phenylenedimaleimide orm-maleimidobenzoyl-N-hydroxysuccinimide ester showed that the binding of Ca2+ to the δ subunit triggers changes in the interactions among all subunits, including between protomers, indicating an extensive communication network throughout the PbK complex. Most of the structural effects of δ′/Ca2+were qualitatively similar to, but quantitatively greater than, the effects of Ca2+ alone; but δ′/Ca2+ also had distinct effects, especially involving cross-linking of the δ subunit.
Release of bovine luteinizing hormone by purified porcine and synthetic gonadotropin releasing hormone.

SummaryLH concentration in serum of heifers averaged 0.5 ng/ml and increased to peaks of 1.9, 7.3 and 11.1 ng/ml after a single iv injection of 5, 20 or 80 μg GnRH, respectively. Similarly, LH concentration in serum from mature bulls averaged 1.1 ng/ml before GnRH and increased to peaks of 9.2, 19.3 and 39.1 ng/ml after 10, 40 and 160 μg GnRH, respectively. The interval from GnRH to the LH peak and magnitude of the peak were positively correlated. Exposure of pituitary explants, in constant superfusion, to 1 or 4 ng GnRH increased LH release from a pre-treatment base line of 0.25 ng/mg/min to 0.94 and 1.50 ng/mg/min after 20 min, respectively. LH release did not return to base line by 40 min after exposure to GnRH. A comparison of purified porcine and synthetic GnRH revealed parallel increases in media LH concentration with time after GnRH.
Biotin-functionalized poly(ethylene terephthalate) capillary-channeled polymer fibers as HPLC stationary phase for affinity chromatography.

Native poly(ethylene terephthalate) (PET) capillary-channeled polymer (C-CP) fibers have been used as the stationary phase for high-performance liquid chromatography (HPLC) of proteins via reversed-phase and ion-exchange processes. Functionalization can be used to bring about greater selectivity through surface modification. PET fibers were treated with ethylenediamine to generate primary amine groups on the fiber surface, enabling subsequent covalent attachment of ligands. The ninhydrin test for primary amines revealed surface densities of 13.9–60.0 μmol m−2 for PET fibers exposed for periods of 3–12 min. Here, 8-amino-3,6-dioxaoctanoic acid was linked to the EDA-treated PET fiber surface as a hydrophilic spacer, and then d-biotin was attached on the end of the spacer as an affinity ligand. The streptavidin binding capacity and binding homogeneity were studied on the biotin-functionalized PET C-CP fiber microbore column. The selectivity of the biotin surface functionalization was assessed by spiking lysate with Texas Red-labeled streptavidin and enhanced green fluorescent protein. Greater than 99 % selectivity was realized. This ligand-coupling strategy from standard solid-phase peptide synthesis used in stationary phase functionalization creates great potential for PET C-CP fiber-packed HPLC columns to perform a variety of chromatographic separations.
A two-phase mixture theory for the deflagration-to-detonation transition (ddt) in reactive granular materials

Abstract In this paper, a two-phase mixture theory is presented which describes the deflagration-to-detonation transition (DDT) in reactive granular materials. The theory is based on the continuum theory of mixtures formulated to include the compressibility of all phases and the compaction behavior of the granular material. By requiring the model to satisfy an entropy inequality, specific expressions for the exchange of mass, momentum and energy are proposed which are consistent with known empirical models. The model is applied to describe the combustion processes associated with DDT in a pressed column of HMX. Numerical results, using the method-of-lines, are obtained for a representative column of length 10 cm packed to a 70% density with an average grain size of 100 μm. The results are found to predict the transition to detonation in run distances commensurate with experimental observations. Additional calculations have been carried out to demonstrate the effect of particle size and porosity and to study bed compaction by varying the compaction viscosity of the granular explosive.
ASSESSING THE CUTTING EFFICIENCY OF DENTAL DIAMOND BURS

This study measured the cutting efficiencies of 15 types of roundend tapered conventional and disposable diamond burs. The results showed that disposable diamond burs had cutting efficiencies that were comparable to those of conventional (multiuse) diamond burs; their use should reduce the risk of clinical cross-infection.
Petriellidium boydii Pachymeningitis Treated with Miconazole and Ketoconazole

A very rare case of Petriellidium boydii pachymeningitis is described. Rarer still is the stabilization of this case for a prolonged period. Miconazole and ketaconazole both seemed useful in the treatment, and their role is discussed.
Reply to the Editor–XXXXX

In their article, Drs Ho and Yin describe an elegant case of permanent form of junctional reciprocating tachycardia in a patient with atrial enlargement. The authors provide an excellent explanation for their diagnostic approach and how they determined the underlying mechanism of the tachycardia. The change in the AH interval due to the loss of the left-sided input to the atrioventricular node, which is reflected in delay to the coronary sinus, is a reasonable explanation for the change in RP and tachcardia cycle length (TCL). However, what is less clear from their study is that counterclockwise block at the site of the cavotricuspid isthmus (CTI) is the explanation for this sudden delay to the coronary sinus. The authors specifically describe the accessory pathway location as “posteroseptal,” which would put it medial to the CTI. Yet, to achieve counterclockwise block in the CTI, as the authors describe, the atrial insertion of the accessory pathway would need to be located lateral to the isthmus. Either more information is needed to support the authors’ contention (such as a fluoroscopy image of the ablation and duodecapolar catheters), or they might consider an alternative explanation.
Temperature dependence of DCDD/F isomer distributions from chlorophenol precursors

Abstract The temperature dependence of the gas-phase, rate-limited formation of dichlorodibenzo- p -dioxin (DCDD) and dichlorodibenzofuran (DCDF) isomers from 2,6-dichlorophenol and 3-chlorophenol, respectively, has been studied experimentally in an isothermal flow reactor over the range 300–900°C under pyrolytic, oxidative and catalytic conditions and computationally using semi-empirical molecular orbital methods. At high temperatures, distributions of sets of DCDD/F condensation products are consistent with the calculated thermodynamic distributions, indicating that the relative rates of formation are governed by differences in symmetry and steric hindrance present in the isomer product structures. At low temperatures, however, this is not the case. In the case of 1,6- and 1,9-DCDD formed from 2,6-dichlorophenol via Smiles rearrangement, the 1,6 isomer is favored at low temperatures more than thermodynamically predicted. This result appears to be consistent with kinetic effects of either the expansion of the five-membered ring Smiles intermediate or a lower activation energy six-membered ring intermediate pathway that produces only the 1,6 isomer. For formation of 1,7-, 3,7- and 1,9-DCDF from 3-chlorophenol, the 1,7 isomer fraction increases at low temperatures whereas thermodynamics predicts a decrease. This result can be attributed to steric effects in alternative “sandwich-type” approach geometries of phenoxy radicals to form the o , o ′ -dihydroxybiphenyl (DOHB) intermediate via its keto-tautomers. Higher level molecular theory (ab initio) is needed to provide a more quantitative description of these kinetics.
THE CONTRIBUTIONS OF ERIC TRIST TO THE SOCIAL ENGAGEMENT OF SOCIAL SCIENCE

This article addresses the contributions of Eric Trist to the social sciences. Among his contributions to the literature are the formulation of sociotechnical systems theory; the conceptualization of sell-directed work teams; the development of the notion of organizations as open systems in the context of environments with unique causal textures; the formulation of social ecology as a new field of inquiry; and the creation of processes for bringing about change on the individual, group, organizational, and interorganizational levels. Underlying all of his theoretical contributions is his innovative work with groups, organizations, and communities around the world, reflecting his commitment to social science that is socially engaged in the service of humanity.1
The Effect of Feather Muscle Receptor Stimulation on Intrafollicular Pressure, Feather Shaft Movement and Feather Release in the Chicken,

Abstract INTRODUCTION OSTMANN et al. (1963) found that feathers were loosened by both local and general anesthetics by tranquilizing drugs such as chlorpromazine and promazine and by the neural blocking drugs atropine and yohimbine. On the other hand, adrenergic and cholinergic drugs had no effect on altering feather pulling force. In addition, Ostmann et al. (1964) observed that all levels of spinal transaction significantly reduced feather pulling force posterior to the level of transection. The present investigation was undertaken to determine if the feather muscles have adrenergic (alpha and/or beta) and cholinergic receptors. In addition to the above, the effects of feather muscle receptor stimulation on intrafollicular pressure, feather release and feather shaft movement were also studied. METHODS The pressure within the feather follicle (intrafollicular pressure or IFP) was measured using a technique developed by Peterson and Ringer (1964). Non-molting mature S. C. White Leghorn-type hens were used throughout the experiments. . . .
A Phase II trial of CPT-11 in recurrent squamous carcinoma of the cervix : A gynecologic oncology Group study

Abstract Objective. To determine the response rate and associated toxicity of weekly CPT-11 in squamous carcinoma of the cervix. Methods. From October 1994 to May 1996, the Gynecologic Oncology Group (GOG) conducted a Phase II trial in patients with recurrent squamous cervix carcinoma. The schedule employed weekly ×4 intravenous CPT-11 at 125 mg/m 2 followed with a 2-week rest, to be repeated until disease progression or unacceptable toxicity. Eligibility criteria were a GOG performance status of 0–2, adequate bone marrow reserve, adequate liver function, and serum creatinine Results. Fifty-four patients were entered into the trial. Three patients were ineligible because of wrong cell type ( N = 2) or inadequate pathology material ( N = 1). Two were inevaluable because of inadequate trial of drug. An additional 4 patients were inevaluable for response. Thus, 49 were evaluable for toxicity and 45 were evaluable for response. The median age of patients was 45 years (range, 29–71 years). The median number of weekly doses delivered was 7 (range, 1–46). The incidence of grade 4 neutropenia and anemia was 6.1 and 4.1%, respectively. Nineteen patients (38.8%) developed gastrointestinal (GI) toxicity including 8 with grade 3 and 11 with grade 4 severity. The overall response rate was 13.3% (6/45). There was 1 patient death from GI toxicity. There was one complete response of 8.8 months duration and 5 partial responses. Conclusion. This schedule of CPT-11 exhibits modest activity with moderate toxicity in patients with recurrent squamous carcinoma of the cervix.
Oxidative dehydrogenation of cyclohexene on size selected subnanometer cobalt clusters: improved catalytic performance via evolution of cluster-assembled nanostructures

The catalytic activity of oxide-supported metal nanoclusters strongly depends on their size and support. In this study, the origin of morphology transformation and chemical state changes during the oxidative dehydrogenation of cyclohexene was investigated in terms of metal-support interactions. Model catalyst systems were prepared by deposition of size selected subnanometer Co(27±4) clusters on various metal oxide supports (Al(2)O(3), ZnO and TiO(2) and MgO). The oxidation state and reactivity of the supported cobalt clusters were investigated by temperature programmed reaction (TPRx) and in situ grazing incidence X-ray absorption (GIXAS) during oxidative dehydrogenation of cyclohexene, while the sintering resistance monitored with grazing incidence small angle X-ray scattering (GISAXS). The activity and selectivity of cobalt clusters shows strong dependence on the support. GIXAS reveals that metal-support interaction plays a key role in the reaction. The most pronounced support effect is observed for MgO, where during the course of the reaction in its activity, composition and size dynamically evolving nanoassembly is formed from subnanometer cobalt clusters.
Fast linear programming state estimation using the dual formulation

The authors present a fast and efficient technique for solving the power system state estimation problem using linear programming (LP). The dual formulation of the original problem is described. This formulation improves the solution time significantly. Four LP state estimators are presented and test results on the IEEE 30, 57, and 118 bus standard systems are included. Both the full and decoupled dual problems were solved. Test results indicate that the dual estimators are superior to the primal estimators. >
Isolation and characterization of a mouse betaine-homocysteine S-methyltransferase gene and pseudogene

Betaine-homocysteine S-methyltransferase (BHMT) is one of the enzymes involved in the branch point metabolism of homocysteine. Elevated levels of plasma homocysteine may be a risk factor for the development of vascular disease; however, whether BHMT has a significant role in the regulation of plasma levels of homocysteine remains to be determined. As a prelude to creating a mouse strain deficient in BHMT activity, we screened a lambda library containing mouse SvJ 129 genomic DNA for the mouse BHMT gene using random probes made from the human cDNA. One genomic isolate was completely sequenced and found to encode an intronless BHMT pseudogene (mBHMT-ps). mBHMT-ps was then used as a template for the generation of random probes that were used to screen a BAC library containing mouse 129 Sv/Ev genomic DNA. In order to discriminate between pseudogenes and the authentic BHMT gene, a secondary PCR-based screen was employed which used primers designed from the pseudogene sequence that would predictably amplify across introns. Using this strategy, we isolated six mouse genomic clones that tested positive for the presence of all seven introns characteristic of the human gene, and the BHMT gene of one clone was completely sequenced. Like the human BHMT gene, the mouse gene spans 21kb and is encoded by eight exons interrupted by seven introns. The structure of the mouse BHMT gene is described herein as well as the 5'-flanking region of the gene adjacent to exon 1, which we demonstrate is capable of conferring basal promoter activity in Chinese Hamster Ovary cells.
A novel tricyclic pyrazine from lysine hydrochloride pyrolysis

Abstract The pyrolysis of lysine hydrochloride at 600° yields a novel ditetrahydroazepinopyrazine (I).
Epileptiform activity extinguished by amygdala infusion of the neurotoxin ibotenate in a rat model of temporal lobe epilepsy.

Object. The long-term antiseizure effects of local convection-enhanced infusion of the excitotoxin ibotenate were examined in a rat model of temporal lobe epilepsy. Methods. A single injection of kainate, an epileptogenic excitatory amino acid, into the left amygdala elicited chronic spontaneous recurrent seizure activity for at least 36 days after the injection. Two weeks after the injection, infusion of ibotenate, a nonepileptogenic excitatory amino acid that is an axon-sparing neuronal cell toxin, into the left amygdala and piriform lobe induced immediate and permanent extinction of electrical and behavioral seizure activity. Conclusions. Lesioning of an epileptic focus by convective distribution of ibotenate can produce an enduring suppression of seizure activity, indicating a chemical neurosurgical approach for epilepsy therapy.
On phase transitions of elastic continua

An elastic body undergoing a phase transition is modelled as a mixture of the two separate phases. Classical results for liquid-gas transitions are obtained from the relevant Clausius-Duhem inequality and their counterparts derived for a particular class of solid-solid transitions.
Transgenic crops why gene flow matters.

OMMENTARY542Several key challenges face researchersattempting rigorous empirical assessment ofgene flow from genetically modified (GM)crops to related commercial crops, weeds,and wild relatives. A workshop held recentlyat Ohio State University (Columbus, OH)*brought together plant population ecolo-gists, evolutionary biologists, weed ecolo-gists,crop scientists,and molecular biologiststo discuss progress in the field and appropri-ate methods for studying questions related togene flow, with an emphasis on crops andrelated species in North America. Clearly,there is a paucity of interdisciplinary researchon the ecological and agronomic effects ofgene flow,and increased public investment inthis type of research is sorely needed .Gene flow from crops to wild or weedy rel-atives is often cited as a potential risk in thecommercialization of transgenic crops
Understanding the pathophysiology of postpartum depression: implications for the development of novel treatments.

Depression during pregnancy and in the postpartum period is common, devastating to mothers and their offspring, and poorly understood in terms of pathophysiology. In this issue of Neuron , Maguire and Mody provide evidence for a role for aberrant neurosteroid regulation of the GABA A receptor subunit in the etiology of postpartum depression, presaging elucidation of the pathophysiology and development of treatments of this depression endophenotype.
A Search for Sodium Absorption from Comets around HD 209458

We monitored the planet-bearing solar-type star HD 209458 for sodium absorption in the region of the stellar Na I D1 line that would be indicative of cometary activity in the system. We observed the star using the Hobby-Eberly Telescope High Resolution Spectrograph with a high signal-to-noise ratio (S/N) and high spectral resolution for six nights over the course of 2 years, from 2001 July to 2003 July. From modeling we determine a 20% likelihood of a detection, based on a predicted number of comets similar to that of the solar system. We find that our analytical method is able to recover a signal and that our S/N is sufficient to detect this feature in the spectral regions on either side of the core of the D1 line, where it is most likely to appear. No significant absorption was detected for any of the nights based on a 3 σ detection limit. We derive upper limits on the column density of sodium of 6 × 109 cm-2 for a signal in the region around the line core and 2 × 1010 cm-2 for a signal in the core of the photospheric D1 line. These numbers are consistent with the sodium released in a single periodic comet in our own system, although a higher S/N may be necessary to uncover a signal in the core of the D1 line. Implications for cometary activity in the HD 209458 system are discussed.
Topological synthesis of compliant mechanisms using multi-criteria optimization

Compliant mechanisms are mechanical devices that achieve motion via elastic deformation. A new method for topological synthesis of single-piece compliant mechanisms is presented, using a “design for required deflection” approach. A simple beam example is used to illustrate this concept and to provide the motivation for a new multi-criteria approach for compliant mechanism design. This new approach handles motion and loading requirements simultaneously for a given set of input force and output deflection specifications. Both a truss ground structure and a two-dimensional continuum are used in the implementation which is illustrated with design examples.
Pre-copulatory courtship behavior in a solitary bee, Nomia triangulifera Vachal (Hymenoptera : Halictidae)

Comportement de cour precopulatoire chez une abeille solitaire, Nomia triangulifera Vachal (Hymenoptera, Halictidae). L'abeille terricole, Nomia triangulifera, presente un comportement de cour complexe avant et pendant l'accouplement. Le comportement d'accouplement a ete etudie sur de grosses aggregations dans une ferme du Nord-Est du Kansas, ou les abeilles nidifient depuis de nombreuses annees. En 1989 et 1990, on a capture des abeilles qui emergeaient afin de determiner la phenologie de l'emergence et d'estimer le sex-ratio journalier d'accouplement (nombre de mâles presents/nombre de femelles receptives)
Molecular orbital studies on the optical activity of chiral nitrosamines and nitramines

Abstract The chiroptical properties of the two lowest energy singlet-singlet transitions in a series of N-nitrosopiperidine derivatives are examined on a CNDO/S-CI molecular orbital (MO) model in which rotatory strengths are calculated directly from total molecular electronic wave functions. Similar calculations are carried out for the three lowest energy singlet-singlet transitions in a series of chiral N-nitropiperidine derivatives. The results obtained for the low energy n→π * transitions in these compounds are compared to those predicted by sector rules proposed for chiral N-nitrosamine and N-nitramine systems.
METHODOLOGICAL NOTES ON A THEORY OF STATUS CRYSTALLIZATION

Theories of status crystallization are among-the major new ideas which have entered sociological thinking within the past decade. Although these theories, of which there are several branch developments, can be traced to Weber's concern with multiple hierarchies of stratification, the generally recognized locus of current thinking on this topic is Emile Benoit-Smullyn,' who specifically raised the notion of equilibration among the ranks held by a single person over several hierarchical dimensions. Gerhard Lenski extended and applied this theory further in his two well-known articles, "Status Crystallization: A Non-vertical Dimension of Social Status" and "Social Participation and Status Crystallization."2 Lenski and others in this tradition are concerned with the pattern or configuration of ranks a person holds. This concern with the pattern rather than with the level of ranks has been called, as noted in Lenski's title, "a non-vertical dimension of social status." A person whose ranks are all at the same relative level, high or low, is said to have a high degree of status crystallization, status congruency, or equilibrated ranks. In this case, the old-stock Episcopalian banker and the Negro charwoman would receive the same crystallization score. A person with an uneven pattern of ranks, such as the old-stock Episcopalian charwoman or the Negro banker, has a low degree of status crystallization and, as a consequence, is considered to be under some stress, which then leads to a reaction in response to this stress. Several recent studies have found that the pattern of ranks people