cssi/SciSciGPT-SciSciNet huggingface dataset:
Fischer–Tropsch synthesis: study of the promotion of Re on the reduction property of Co/Al2O3 catalysts by in situ EXAFS/XANES of Co K and Re LIII edges and XPS

A direct relationship between the Fischer–Tropsch synthesis (FTS) rate and the number of surface cobalt atoms available for reaction is usually obtained. For Co/Al2O3 catalysts in particular, the site density depends on two primary factors: (1) the average size of the cobalt clusters on the support; and (2) the fraction of cobalt reduced to the metallic state. The addition of small amounts of noble metal promoters, such as Pt and Ru to cobalt alumina, may catalyze the reduction of cobalt oxide shifting the temperature of reduction of both steps (Co3O4→CoO and CoO→Co0) to lower temperatures. However, Re affects only the second step. Re is reduced at a higher temperature than Pt or Ru, and at approximately the same temperature as the first step of cobalt reduction (Co3O4→CoO). Thus, Re metal is present to catalyze only the second step. In situ extended X-ray absorption fine structure (EXAFS) at the LIII edge of Re has been used to show that there is direct contact of Re with cobalt atoms, while evidence for ReRe bonds is not observed. Even though direct atom-to-atom contact is found, temperature-programmed reduction (TPR) suggests that hydrogen spillover from the promoter to cobalt oxide clusters is important for the catalysis of cobalt oxide reduction. In situ EXAFS at the K edge of Co shows that the average cobalt cluster size decreases with increasing Re loading. Re promotes reduction of smaller species which interact with the support, and therefore, for a given reduction temperature, the average cobalt metal cluster size decreases as a function of increasing Re content. After reduction at a temperature slightly above the first peak in the TPR (Co3O4→CoO), the species remaining on the surface displayed XANES spectra identical to that of CoO. After reduction at a temperature above the second broad TPR peak, XPS showed that a residual oxide species was present, with a binding energy equivalent to cobalt aluminate.
Non-BornOppenheimer coupling of phonons to the S0⇌S1 transition in crystalline benzene

Abstract The nature of weak electronphonon coupling in molecular crystals is discussed briefly. Experimental techniques are suggested for differentiating between linear, quadratic and vibronic HerzbergTeller or non-BornOppenheimer coupling mechanisms. The coupling of phonons to the benzene S 0 ⇌S 1 transition is examined in light of recently reported experimental results. It is found that non-BornOppenheimer vibronic coupling plays an important role in determining the intensity and structure of the observed phonon sidebands.
Lack of correlation between mutagen-induced chromosomal univalency and aneuploidy in mouse spermatocytes.

Abstract Aneuploidy represents the predominant type of chromosomal abnormality found in human newborns with birth defects. The concern that environmental agents may cause aneuploidy in germ cells has prompted development of assay systems for detection of potentially aneuploidy-producing agents. One of the most frequently used methods involves cytogenetic analysis of murine spermatogenic cells at the stages of meiotic metaphases. However, criteria for aneuploidy induction have not been standardized in this test system. Many investigators consider the ability of an agent to induce univalents an appropriate measure of its potential to induce aneuploidy. In the present study, the relationship between univalency and aneuploidy was examined in mouse spermatocytes after various mutagen treatments. 45 Swiss mice were treated with 4 different agents; viz., adriamycin vinblastine sulfate, cytosine arabinoside, and radiation (cobalt 60) and 10 untreated animals served as controls. From each animal, 50–200 MIs were examined for both sex-chromosomal and autosomal univalency (X-Y U and AU), and equal numbers of MIIs were examined for aneuploidy (hyperhaploidy). No significant correlations between univalency (either X-Y U or AU) and aneuploidy were found in the mutagen-treated mice; nor were they found in the untreated animals. These results indicate that induction of univalents by a mutagen is not necessarily predictive of the aneuploidy-inducing ability of his agent.
LumiNOC: A Power-Efficient, High-Performance, Photonic Network-on-Chip

To meet energy-efficient performance demands, the computing industry has moved to parallel computer architectures, such as chip multiprocessors (CMPs), internally interconnected via networks-on-chip (NoC) to meet growing communication needs. Achieving scaling performance as core counts increase to the hundreds in future CMPs, however, will require high performance, yet energy-efficient interconnects. Silicon nanophotonics is a promising replacement for electronic on-chip interconnect due to its high bandwidth and low latency, however, prior techniques have required high static power for the laser and ring thermal tuning. We propose a novel nano-photonic NoC (PNoC) architecture, LumiNOC, optimized for high performance and power-efficiency. This paper makes three primary contributions: a novel, nanophotonic architecture which partitions the network into subnets for better efficiency; a purely photonic, in-band, distributed arbitration scheme; and a channel sharing arrangement utilizing the same waveguides and wavelengths for arbitration as data transmission. In a 64-node NoC under synthetic traffic, LumiNOC enjoys 50% lower latency at low loads and ${\sim}{40\%}$ higher throughput per Watt on synthetic traffic, versus other reported PNoCs. LumiNOC reduces latencies ${\sim}{40\%}$ versus an electrical 2-D mesh NoCs on the PARSEC shared-memory, multithreaded benchmark suite.
State-dependent executive deficits among psychopathic offenders.

Three hypotheses for cognitive deficits among psychopaths were tested: Response modulation, left hemisphere activation, and an interaction between the 2. Twenty-six psychopathic and 32 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist–Revised were randomly assigned to left- and right-hemisphere activation groups. An auditory processing task was administered, such that the ability to classify nonverbal auditory signals and the ability to manage subgoals were assessed under left- and right-hemisphere activation conditions. The results showed that psychopaths' information processing in general, including response modulation, was deleteriously affected by left-hemisphere activation, supporting 2 of the 3 hypotheses tested. These results offer an explanation for inconsistent findings of executive deficits among psychopaths. ( JINS , 2005, 11 , 311–321.)
A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology

Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs.
Deafness mutation mining using regular expression based pattern matching

Background While keyword based queries of databases such as Pubmed are frequently of great utility, the ability to use regular expressions in place of a keyword can often improve the results output by such databases. Regular expressions can allow for the identification of element types that cannot be readily specified by a single keyword and can allow for different words with similar character sequences to be distinguished.
Alkanethiol Monolayers Contain Gold Adatoms, and Adatom Coverage Is Independent of Chain Length

The nature of the sulfur−gold bond in alkanethiol films self-assembled on Au(111) surfaces is widely contested, despite significant interest in these systems over the last 25 years. Recent theoretical and experimental studies have suggested gold adatoms are incorporated into the alkanethiol−gold interface. We have exposed alkanethiol self-assembled monolayers (SAMs) to gas-phase hydrogen atoms to remove the monolayer; the gold adatoms remain on the surface and form features that we observe using scanning tunneling microscopy (STM). The features include the formation of single-atom-thick gold islands, decreasing size of surface vacancy pits, and faceting of terrace step edges; compared to the alkanethiol-terminated surface, these features indicate a net increase in the amount of gold present on the surface, compared to the alkanethiol-terminated bulk structure. Varying the length of the alkane chain does not affect the total adatom coverage, as the adatom coverages for ethanethiol (0.172 ± 0.039), octaneth...
A Test Characteristic Curve Linking Method for the Testlet Model

When tests are made up of testlets, a testlet-based item response theory (IRT) model may be used to account for local dependence among items from a common testlet. This study presents a new test characteristic curve method to link calibrations based on the Bradlow, Wainer, and Wang (1999) testlet model. Procedures for calculating the test characteristic curve linking coefficients are developed. The effectiveness of the method is investigated using simulated data. Results suggest that the linking coefficients are accurately recovered and superior to those obtained when using a traditional IRT model to link calibrations when testlet-based local dependence is present. A real data example illustrates the proposed linking method.
Discrete Event Models for Cell Space Simulation

Cellular automata are a well-known class of models that characterize many of the essential properties of spatially distributed parallel systems. At a yet more fundamental level, Burks has employed the cellular automaton modeling formalism to formalize what is meant by “law of nature.” In this article, we introduce a broader class of spatially distributed models called discrete event cell space models. Comparing the old and new formalisms as adequate and convenient vehicles for representing various natural and artificial systems, we suggest the potential of the discrete event approach for modeling at the level of fundamental physics.
Two Simple Bridges for Very-High-Frequency Use

Two bridge circuits for impedance measurement at very-high frequency are described. The first is a hybrid junction tunable over the 100 to 500-Mc range, and capable of great sensitivity. The second is an untuned Wheatstone type for service over the same frequency range. Design features and sample performance characteristics are given for both units.
Scientific Method and Social Problems

SCIENTIFIC cial sciences methodology has, somewhat in the decepsoS IENTIFIC cial sciences has, somewhat d cep tively, an appearance of definiteness. There is an intellectual unity of aim and procedure in all science ; but to discuss this with any clarity requires definition of terms. Men have long tried to fix science within a rigid definition, and have not agreed. Much unnecessary and unhelpful debate about the scientific standing of the social disciplines has been based on uncertain and divergent premises as to what constitutes science. To Francis Bacon science was unbiased observation of nature and inductive reasoning to generalizations. This was a good start. Some positivists have wished to limit science to ob-
θ-point temperature and exponents for the bond fluctuation model

Abstract We calculate the θ-temperature and the associated critical exponents for the bond fluctuation polymer model of Carmesin and Kremer in two dimensions. The critical exponent values are in agreement with the theoretical predictions. We find that the extra mobility introduced by the flexible bond serves to shift the crossover to the ideal tricritical behavior to a shorter polymer length, compared with previously studied lattice models. In particular, bond-flexible simulations with polymer lengths of the order of 50 already successfully reproduce the properties of infinite chains.
The American Society of Pain Management Nurses practice analysis: Role delineation study

A role delineation study was carried out by the American Society of Pain Management Nurses (ASPMN) to determine the activities performed by nurses involved in pain management. Demographic characteristics of pain management nurses and differences in practice based on educational preparation and specialty affiliation were identified. The role delineation survey was developed based on Nursing Intervention Classifications. The survey consisted of 91 activity statements. Respondents rated the frequency of performing each activity and the importance of the activity. A Mean Activity Index score was calculated for each item. All members of the ASPMN, the nursing special interest group (SIG) of the American Pain Society, and the pain SIG of the Oncology Nursing Society, as well as random samples of members of the National Association of Orthopaedic Nurses, Hospice and Palliative Nurses Association, American Association of Nurse Anesthetists, American Association of Critical Care Nurses, and American Academy of Nurse Practitioners were surveyed. Seven hundred and sixty-one questionnaires were analyzed (24.8% response rate). Demographic characteristics of the sample mirrored those of nursing as a whole in the United States. The activities with the highest Mean Activity Index were primarily those involving assessment of pain. Nurses with diploma and Associate Degree preparation rated assessment and nonpharmacologic management higher and communication and collaboration lower than nurses with higher educational preparation. Activities varied somewhat as a reflection of respondents' nursing specialty. The results of the study will be used to refine standards of care, develop nursing education curricula, develop research priorities, and develop a blueprint for a certification examination in pain management nursing.
Assessing the Impact of Tutorial Services

Many institutions struggle to develop a meaningful way to assess the effectiveness of drop-in tutorial services provided to students. This article discusses the development of a data collection system based on a visitor sign-in system that proved to be an efficient method of gathering assessment data, including frequency of visits, end-of-course grades, and demographic information on student visitors. The data were used to analyze the impact of tutorial services on student grade rates, with special attention given to the effects of service on populations underrepresented (females and Blacks) in science, technology, engineering, and mathematics (STEM) fields. The results showed a significant difference in grade distributions among Black males and provided evidence to support the existence of self-selection biases in the use of tutorial services. The biases may include self-selected use of tutorial services by at-risk students, who are more likely to need support, and by self-motivated students, who are mor...
Technology Lecture Developments in scientific information systems

Publication of scientific papers has grown in size and range since the middle of the 17th century. The system is now large, costly and slow, and a report published by the Royal Society and the British Library in 1981 concluded that a combination of pressures would put it under considerable strain. ‘Electronic journals’ as substitutes for print on paper have attracted attention over the past decade but, although a number of systems have been developed for communication, no completely electronic primary publication yet exists. The application of technology can improve aspects of the system, but it is first necessary to consider the needs of users and the objectives, nature and limitations of present publishing. Technology has already been applied extensively to secondary publications such as abstracts and the lecture therefore concentrates on application to full length papers.
Some properties of Chebyshev approximation in a subspace of Rn

Abstract Let K be a subspace of R n and let K ⊥ be the orthogonal complement of K . Rockafellar has shown that certain properties of K may be characterized by considering the possible patterns of signs of the nonzero components of vectors of K and of K ⊥ . Such considerations are shown to lead to the standard characterization theorem for discrete linear Chebyshev approximation as well as to several results on uniqueness of solutions. A method is given for testing uniqueness of a given solution. A special case related to graph theory is discussed and combinatorial methods are given for solving and testing for uniqueness.
Magnitude and distribution pattern of zinc in oysters

This study was an attempt to assess the magnitude and distribution pattern of trace element zinc in oysters to see if the problem of the magnitude of zinc contamination was evident in the South Carolina Fishery. It would identify potentially hazardous situations and persons affected would be made aware of the problem. Where high zinc concentration are found in oysters, it would then attempt to identify the source of pollution.
Introduction to JEBO Special Issue on 'Issues in the Methodology of Experimental Economics'

It is a pleasure to present to our readers this special issue on Issues in the Methodology of Experimental Economics. While there are no headings to delineate them, this issue consists of three sections. The first consists of a target article by Vernon Smith that is based on a talk given by him at a conference of the Economic Science Association, “Theory and experiment: what are the questions?” It addresses the ongoing question of how economists should deal with the discrepancies that sometimes arise between mainstream neoclassical theory and empirical results found in economic experiments. Of course, sometimes experimental evidence confirms conventional theory, as Smith's own famous work on double auctions has demonstrated (Smith, 1962), while at other times it does not appear to do so, as the majority of studies on the ultimatum game would seem to indicate (Guth et al., 1982). Smith's paper discusses a wide array of cases and issues related to this problem and how they should be dealt with.Attached to this paper are a series of serious commentaries by a distinguished group of observers: Gary Bolton, Gary Charness, James C. Cox, Daniel Friedman, Herb Gintis, David Grether, Werner Guth and Hartmut Kliemt, Glenn W. Harrison, Daniel Houser and Erte Xiao, William S. Neilson, Jorg Oechssler, Elinor Ostrom, Mark Pingle, and Bart Wilson. Needless to say, they provide a diverse array of perspectives and add many cases and issues to the discussion by Smith, which we shall not characterize further here, but hope the readers find them as stimulating as we have. These are followed by a rejoinder by Smith, who emphasizes the relevance to current experimental economics of Adam Smith's (1759) Theory of Moral Sentiments.The second section of this special issue deals more directly with questions of the methodology of how experiments should be done and interpreted by focusing on a critique of one of the most cited papers in experimental economics, the 1999 one by Fehr and Schmidt (1999) on inequity aversion. The critique is contained in a paper by Ken Binmore and Avner Shaked, which is followed by a reply by Fehr and Schmidt, along with an additional commentary by Catherine Eckel and Herb Gintis. Binmore and Shaked provide a brief rejoinder. We note that this discussion involves considerable disagreements among the various authors that remain for the reader to evaluate at the end of this set of papers.The final section of the special issue is a single paper by Rachel Croson and Simon Gachter that returns to the broader themes of the special issue and concludes with a list of ten “do's and don’ts” for experimental economists and the theorists who are sometimes unhappy with what they find. Again, we hope that many readers will find this issue to contain stimulating and informative work that they will find to be of interest.
Lipase-catalyzed esterification of 2-monoricinolein for 1,2 (2,3)-diricinolein synthesis.

The purpose of this investigation was to develop conditions for producing 2-monoricinoleoyl DAG. We used lipase-catalyzed hydrolysis of triricinolein to obtain 2-monoricinolein and thereafter synthesized 1,2(2,3)-diricinolein through esterification of 2-monoricinolein, using ricinoleic acid as the acyl donor. Five different 1,3-specific immobilized lipases were tested for the initial methanolysis reaction: Candida antarctica type B, Rhizomucor miehei, Rhizopus oryzae (ROL), Thermomyces lanuginosus, and Aspergillus niger. For the second esterification reaction, we investigated these five lipases plus Pseudomonas cepacia, Penicillium roquefortii, Candida rugosa, and Pseudomonas fluorescence. Toluene and diisopropyl ether (DIPE) were examined as reaction media at a water activity of 0.11. ROL in DIPE gave the highest yield of 2-monoricinolein from triricinolein, 78% after 3 h of reaction. The isolated 2-monoricinolein was esterified with ricinoleic acid for synthesis of 1,2(2,3)-diricinolein. ROL in DIPE gave the highest yield of 1,2(2,3)-diricinolein, 58% after 1 h of reaction, and NMR analysis showed that the purity was 97.2%. This methodology can used for synthesizing radiolabeled 1,2(2,3)-diricinolein to study lipid biosynthesis in castor and other oilseeds.
Rational choice and polynomial measurement models

Abstract Rational choice behavior is defined in a manner that subsumes rational choice theory as part of general measurement theory. The special class of polynomial measurement problems are defined, and their solutions are reduced to solving polynomial inequalities. An algebraic criterion is given for the solvability of arbitrary finite sets of polynomial inequalities, resolving a conjecture of Tversky.
Some properties of electron beam evaporated amorphous Mo-N films*

A series of amorphous Mo-N films was prepared by electron beam evaporation of molybdenum in varying partial pressures of nitrogen and deposited onto substrates cooled to about 80 K. The alloy films were characterized by X-ray diffraction, the superconducting transition temperature,Tc, and the crystallization temperature,Tx. The maximumTc (8.3 K) and sharpest transition occurred with the minimum nitrogen pressure necessary to form the amorphous structure, as revealed by X-ray diffraction. After annealing the as-deposited films, both bcc and fcc phases were found with the bcc/fcc ratio decreasing with increasing nitrogen partial pressure. Differential scanning calorimetry (DSC) measurements showed significant differences in the shape of peaks associated with either bcc, bcc+fcc, or fcc phases. The temperature,Tx, associated with the fcc crystallization increased with nitrogen content. Heats of crystallization had an average value of about 63 J g−1. Changes in position of the first amorphous X-ray diffraction peak showed that the amorphous structure was expanded by increasing nitrogen content.
Hemolysis in Identifying Eaton's Pleuropneumonia-Like Organism

A method for readily demonstrating hemolysis of mammalian erythrocytes by Eaton's pleuropneumonia-like organism is described. This reaction may be useful in preliminary identification of this organism, since other strains from human sources are not known to have this property.
Thermal analysis: An alternative method of measuring oil stability

Preliminary results using three different thermal analysis techniques to evaluate the relative oxidative stabilities of five vegetable oil samples yielded good correlations with the predicted stabilities by the active oxygen method. The thermal analysis techniques offer the advantages of good quality control time, being less empirical, and requiring limited equipment and operator expertise. In addition, these techniques should be useful in evaluating oil-processed finished products as well as the oils themselves.
Lower Cretaceous peritidal limestones at 2,700-m depth, Blake nose, Atlantic Ocean

At sites 390 and 392 (Deep Sea Drilling Project, Leg 44) on the Blake nose, thoroughly lithified Lower Cretaceous limestone more than 250 m thick is abruptly overlain by a condensed sequence of Barremian to Eocene pelagic carbonate ooze. The Lower Cretaceous sediments consist of three units: limestone with moldic porosity (base), oolitic limestone, and fenestral limestone. Subaerial diagenesis of the limestone section is recorded by (1) caverns with vertical dimensions of up to 10 m, (2) stalactitic intergranular cement, and (3) meniscus sediment (or cement). Compatible with these subaerial features are mud cracks, fenestral fabrics, intraclasts, and cryptalgal structures. Inasmuch as these shallow-water and tidal-flat deposits are now beneath 2,607 m of sea water (plus 99 m of younger sediments), they serve to dramatize the apparent degree of Barremian and later subsidence of this part of the Atlantic outer continental shelf. Porosity and permeability are high in vuggy samples, which are common in the skelmoldic limestone. Cementation has destroyed most of the extensive primary porosity of the two younger units.
A Numerical Study of Sea-Breeze-Driven Ocean Poincare Wave Propagation and Mixing near the Critical Latitude

Abstract Near the vicinity of 30° latitude, the coincidence of the period of sea breeze and the inertial period of the ocean leads to a maximum near-inertial ocean response to sea breeze. This produces a propagating inertial internal (Poincare) wave response that transfers energy laterally away from the coast and provides significant vertical mixing. In this paper, the latitudinal dependence of this wave propagation and its associated vertical mixing are investigated primarily using a nonlinear numerical ocean model. Three-dimensional idealized simulations show that the coastal oceanic response to sea breeze is trapped poleward of 30° latitude; however, it can propagate offshore as Poincare waves equatorward of 30° latitude. Near 30° latitude, the maximum oceanic response to sea breeze moves offshore slowly because of the near-zero group speed of Poincare waves at this latitude. The lateral energy flux convergence plus the energy input from the wind is maximum near the critical latitude, leading to increa...
Ambient molecular imaging by desorption electrospray ionization mass spectrometry

Desorption electrospray ionization (DESI) allows the direct analysis of ordinary objects or pre-processed samples under ambient conditions. Among other applications, DESI is used to identify and record spatial distributions of lipids and drug molecules in biological tissue sections. This technique does not require sample preparation other than production of microtome tissue slices and does not involve the use of ionization matrices. This greatly simplifies the procedure and prevents the redistribution of analytes during matrix deposition. Images are obtained by continuously moving the sample relative to the DESI sprayer and the inlet of the mass spectrometer. The timing of the protocol depends on the size of the surface to be analyzed and on the desired resolution. Analysis of organ tissue slices at 250 microm resolution typically takes between 30 min and 2 h.
Estrogen regulates angiotensin AT1 receptor expression via cytosolic proteins that bind to the 5' leader sequence of the receptor mRNA.

Abstract. Two of the most highly recognized factors implicated in the pathogenesis of hypertension, atherosclerosis, congestive heart failure and associated cardiovascular disease are the renin angiotensin system (RAS) and estrogen. A major effect of estrogen results from its influence on the RAS. β-estradiol (E2) replacement in ovariectomized (OVX) rats significantly decreased type 1 angiotensin (AT1) receptor expression in the pituitary and adrenal, whereas it significantly increased receptor expression in the uterus when compared to OVX controls. Additional evidence demonstrated an important influence of estrogen on a recently discovered post-transcriptional mechanism for regulating expression of the AT1 receptor. This mechanism consists of cytosolic RNA binding proteins (BPs) that recognize the 5′ leader sequence (5′LS) of the receptor mRNA. The activities of these 5′LS BPs were modulated by estrogen in an inverse manner to AT1 receptor regulation. Moreover, in vitro translation assays in wheat germ l...
Overt and Covert Aspects of Adult Speech Perception

The relationship between verbal report and cardiac orienting response measures of speech discrimination in adult listeners was examined in two experiments using stimuli and paradigms previously emp...
Beam shaping with vectorial vortex beams under low numerical aperture illumination condition

In this paper we propose and demonstrate a novel beam shaping method using vectorial vortex beam. A vectorial vortex beam is laser beam with polarization singularity in the beam cross section. This type of beams can be decomposed into two orthogonally polarized components. Each of the polarized components could have different vortex characteristics, and consequently, different intensity distribution when focused by lens. Beam shaping in the far field can be achieved by adjusting the relative weighing of these two components. As one example, we study the vectorial vortex that consists of a linearly polarized Gaussian component and a vortex component polarized orthogonally. When such a vectorial vortex beam is focus by low NA lens, the Gaussian component gives rise to a focal intensity distribution with a solid centre while the vortex component gives rise to a donut distribution with hollow dark center. The shape of the focus can be continuously varied by continuously adjusting the relative weight of the two components. Under appropriate conditions, flat top focusing can be obtained. We experimentally demonstrate the creation of such beams with a liquid crystal spatial light modulator. Flattop focus obtained by vectorial vortex beams with topological charge of +1 has been obtained.
Binding of 5-fluorodeoxyuridylate to thymidylate synthase in human colon adenocarcinoma xenografts☆

Abstract The formation and stability of the covalent ternary complex formed between thymidylate synthase (E.C. 2.1.1.45), 5-fluoro 2′-deoxyuridylate (FdUMP) and 5,10-methylenetetrahydrofolate ( CH 2 -H 4 PteGlu) has been examined in cytosols derived from xenografts of human colon adenocarcinomas. The rate of association ( k a ) for FdUMP was low being between 3.4 ± 0.9 and 10.2 ± 2.6 × 10 6 M −1 min −1 , with the lowest k a value being determined in cytosols from a tumor (HxELC 2 ) which has demonstrated some sensitivity to 5-fluoropyrimidines. Relative to reported k a values for human leukemic cells, the rate of association of FdUMP was 20- to 59-fold lower. This difference is not a consequence of FdUMP catabolism, or metabolism of CH 2 -H 4 PteGlu. In cytosols the apparent K m values for dUMP (3.6–4.2 μ M ) and [6RS]-CH 2 -H 4 PteGlu (25–26.7 μ M ) were similar to reported values for human enzyme. Data derived from cytosols were similar to those derived using affinity purified enzyme from HxVRC 5 colon adenocarcinoma xenografts. The net dissociation of [6- 3 H ] FdUMP from the covalent ternary complex was 31–33 min in the absence of added CH 2 -H 4 PteGlu, and the rate of dissociation was dependent upon the concentration of cofactor. The concentration of [6RS]-CH 2 -H 4 PteGlu required to stabilize ternary complex derived from HxELC 2 cytosols was slightly lower than that required for the same degree of stabilization of complex formed in cytosols from resistant tumors (HxGC 3 , HxVRC 5 ). Addition of 5-CHO-H 4 PteGlu, 5-CH 3 -H 4 PteGlu, H 2 PteGlu, and PteGlu did not stabilize the covalent complex, but H 4 PteGlu substituted for CH 2 -H 4 PteGlu.
The role of temperature on the structure of liquid Te0.7Se03. between

Abstract Raman scattering measurements are reported on liquid Te0.7Se0.3 between ∼400–600 C. In contrast to recent compositional studies which indicate a structural change from 3-fold to 2-fold bonding, the effect of temperature is not found to modify the 2-fold bonding in this alloy. This result differs from previous models that have related the nonmetal-metal transition to major changes in liquid network short range order. The Raman results imply, in contrast, increased intrachain disorder with temperature.
Scenario-based robust scheduling for collaborative human-UAV visual search tasks

Many decision support algorithms used to aid human decision making provide guarantees of optimal performance when the optimization parameter are perfectly known. However, algorithm performance degrades when the parameters are inappropriately estimated, and furthermore, algorithm performance is also sensitive to the uncertainty arising from human oversight and interaction with the algorithm. This paper discusses decision support in the form of a scheduling algorithm designed to support human search of imagery collected by unmanned aerial vehicles (UAVs). We demonstrate the sensitivity of the algorithm to uncertainty in human search times, and present a new robust formulation for the search recommendation using data obtained from a previous human-in-the-loop experiment. We show that this robust formulation results in fewer constraint violations in the search task recommendations, as well as increased average performance than an algorithm that does not take this uncertainty into account. For the final draft, the goal is to present human-in-the-loop results that confirm the predictions obtained in the simulations.
Intrinsic response of quantum dash lasers under optical modulation

The intrinsic response of quantum dash lasers are measured using a pulse optical modulation technique. Our results show fast well-to-dash carrier capture and intra-dash carrier relaxation with K-factors independent on the pump wavelengths.
Biochemical and genetic identity of alpha-keto acid reductase and cytoplasmic malate dehydrogenase from human erythrocytes.

Summary We have recently shown that cytoplasmic malate dehydrogenase (MDH-s) from several non-human species catalyses the reduction of aromatic alpha-keto acids in the presence of NADH (Friedrich et al. 1987), an activity previously attributed to the enzyme aromatic alpha-keto acid reductase (KAR E.C. 1.1.1. 96). Here we present evidence that this also occurs in humans, and that the previously characterized human KAR is not the product of a genetically distinct locus. Human MDH-s and KAR activities co-migrate after starch gel electrophoresis, and electrophoretic variants of human MDH-s exhibited identical variation for KAR. Both enzymes show almost no electrophoretic variation among human populations of diverse origin. The reduction of aromatic alpha-keto acids is substantially inhibited by malate, the end-product of the MDH reaction. Antibodies raised against purified chicken MDH-s equally inhibited both MDH-s and KAR in chickens and humans. The bulk of the KAR activity in human blood appears to be due to MDH-s, with a minor fraction catalysed by LDH, as is the case in most other species studied. The previous assignment of a gene for KAR to human chromosome 12 in human/Chinese hamster somatic cell hybrids is questioned because interspecific hybrid bands of both MDH-s and LDH appear with slightly different mobility approximately midway between the human and hamster controls in somatic cell hybrid studies, and the meaning of this artifact is discussed. The discovery that MDH reacts with intermediate metabolites of phenylalanine and tyrosine has implications in relation to the mechanism by which mental retardation may be produced in phenylketonuria (PKU), and the effect of MDH inhibition on oxidative phosphorylation in the various tyrosinaemias is discussed.
Completeness of S4 for the Lebesgue Measure Algebra

We prove completeness of the propositional modal logic S4 for the measure algebra based on the Lebesgue-measurable subsets of the unit interval, [0, 1]. In recent talks, Dana Scott introduced a new measure-based semantics for the standard propositional modal language with Boolean connectives and necessity and possibility operators, \(\Box\) and \(\Diamond\). Propositional modal formulae are assigned to Lebesgue-measurable subsets of the real interval [0, 1], modulo sets of measure zero. Equivalence classes of Lebesgue-measurable subsets form a measure algebra, \(\mathcal M\), and we add to this a non-trivial interior operator constructed from the frame of ‘open’ elements—elements in \(\mathcal M\) with an open representative. We prove completeness of the modal logic S4 for the algebra \(\mathcal M\). A corollary to the main result is that non-theorems of S4 can be falsified at each point in a subset of the real interval [0, 1] of measure arbitrarily close to 1. A second corollary is that Intuitionistic propositional logic (IPC) is complete for the frame of open elements in \(\mathcal M\).
Computer science education in business schools

In 1969, the Business School of Georgia State University (GSU) initiated a new program of study leading to the degree Master of Business Information Systems (MBIS). The program has gone through a series of refinements in order to better fulfill its primary objective of developing business systems designers and information analysts who would be responsible for designing, implementing and evaluating computer based information systems in organizations. The lack of a model that may be used for constructing a suitable curriculum led the author to the development of a goal oriented approach for designing curricula. It provides a systematic way of designing a curriculum for an evolving multidimensional field like computer science. This paper describes the factors that led to the development of this approach and its practical advantages.
Sexual selection's impacts on ecological specialization: an experimental test

In many species, individuals specialize on different resources, thereby reducing competition. Such ecological specialization can promote the evolution of alternative ecomorphs-distinct phenotypes adapted for particular resources. Elucidating whether and how this process is influenced by sexual selection is crucial for understanding how ecological specialization promotes the evolution of novel traits and, potentially, speciation between ecomorphs. We evaluated the population-level effects of sexual selection (as mediated by mate choice) on ecological specialization in spadefoot toad tadpoles that express alternative ecomorphs. We manipulated whether sexual selection was present or reversed by mating females to their preferred versus non-preferred males, respectively. We then exposed their tadpoles to resource competition in experimental mesocosms. The resulting distribution of ecomorphs was similar between treatments, but sexual selection generated poorer trait integration in, and lower fitness of, the more specialized carnivore morph. Moreover, disruptive and directional natural selection were weaker in the sexual selection present treatment. Nevertheless, this effect on disruptive selection was smaller than previously documented effects of ecological opportunity and competitor density. Thus, sexual selection can inhibit adaptation to resource competition and thereby hinder ecological specialization, particularly when females obtain fitness benefits from mate choice that offset the cost of producing competitively inferior offspring.
Study of amino and sulfhydryl sites in the sodium pathway in dog red blood cell membranes.

Amino reactive TNBS (2,4,6-trinitrobenzene sulfonic acid), SITS (4-acetamido-4′-isothiocyano-stilbene-2-2′-disulfonic acid), and Zn++, and SH reactive Hg++ were employed to study sodium channels in dog red blood cells. Simultaneous modification of the membrane with both a SH and an amino modifier results in an increase in Na+ permeability which is equal to the sum of their individual effects. This indicates that SH and amino sites are separate units. Three lines of evidence indicate that the amino sites are more superficial than the SH sites. (1) Pretreatment with an amino modifier decreases the effectiveness of subsequent SH modification. (2) SITS, a nonpenetrating amino reagent, enhances Na+ permeability while DTNB, a nonpenetrating SH modifier, is ineffective. (3) Pretreatment of amino sites decreases the apparent affinity of Hg++ for SH sites. In addition, three lines of evidence indicate that TNBS and Zn++ modify different amino sites. First, simultaneous modification with TNBS and Zn++ results in an increase in Na+ permeability equal to the sum of their individual effects. Secondly, Zn++ causes an increase in Na+ permeability in cells previously treated with TNBS. Finally, the pH dependence of Zn++ modification is opposite that for TNBS modification. These pH experiments suggest that Zn++ enhances Na+ permeability by reacting with unprotonated amino sites while TNBS modifies protonated amino sites. It is concluded that the sodium permeability of dog red blood cells is normally limited by superficial amino sites and deeper sulfhydryl sites in the sodium channels.
The membrane lattice: a novel organelle of the Trypanosomatid flagellate leptomonas collosoma.

This report presents the description of a new organelle in a trypanosomatid flagellate. The Leptomonas membrane lattice is a discrete organelle composed of branched and interconnected smooth membrane tubules. These 50-nm tubules frequently form an almost crystalline array. The P-fracture face of the lattice is densely covered with 7.5- to 10-nm intramembrane particles, while the E face contains very few particles. This particle distribution reflects the bilayer continuity observed between the membrane lattice and both the outer membrane of the nuclear envelope and the rough endoplasmic reticulum. The membrane lattice is also frequently associated with the Golgi apparatus and the spongiome tubules of the contractile vacuole apparatus.
The Possibility of Acceleration of Polarized Protons in the Brookhaven AGS

The unexpected importance of high energy spin effects and the success of the 12 GeV Argonne ZGS in jumping many intrinsic and imperfection depolarizing resonances suggests that polarized proton acceleration should be tried at higher energy. The 1977 Ann Arbor Workshop concluded that it might be possible to jump depolarizing resonances in strong focusing synchrotrons. During the past year we have evaluated the possibility of accelerating polarized protons in the Brookhaven AGS. We found that for about $2 million one could obtain a polarized ion source, fast resonance jumping magnets, and 3 polarimeters which should allow acceleration of 1011 to 1012 polarized protons to 23 GeV/c with about 70% polarization or to 26 GeV/c with about 50% polarization.
ASAGA: an adaptive surrogate-assisted genetic algorithm

Genetic algorithms (GAs) used in complex optimization domains usually need to perform a large number of fitness function evaluations in order to get near-optimal solutions. In real world application domains such as the engineering design problems, such evaluations might be extremely expensive computationally. It is therefore common to estimate or approximate the fitness using certain methods. A popular method is to construct a so called surrogate or meta-model to approximate the original fitness function, which can simulate the behavior of the original fitness function but can be evaluated much faster. It is usually difficult to determine which approximate model should be used and/or what the frequency of usage should be. The answer also varies depending on the individual problem. To solve this problem, an adaptive fitness approximation GA (ASAGA) is presented. ASAGA adaptively chooses the appropriate model type; adaptively adjusts the model complexity and the frequency of model usage according to time spent and model accuracy. ASAGA also introduces a stochastic penalty function method to handle constraints. Experiments show that ASAGA outperforms non-adaptive surrogate-assisted GAs with statistical significance.
Comment on “Currency substitution versus dollarization: a portfolio balance model”

Abstract This commentary points out the claim of differentiating currency substitution from dollarization in Alami’s model (published in the Journal of Policy Modeling , 2001) which relies on the sign between FCDs and income, is problematic. To assess the level of currency substitution in a dollarized economy, the basic measurement, based on the portion of short-term FCDs in the M1 aggregate, may still prove valuable for gaining useful insight. Therefore, in terms of modeling, Cuddington’s model (1983) is superior to Alami’s, and should remain the model of choice for currency substitution and dollarization work.
Nanocomposite Fiber Systems Processed from Fluorinated Single-Walled Carbon Nanotubes and a Polypropylene Matrix

Processing composites of carbon nanotubes into nanotube continuous fibers (NCFs) is an effective way of manipulating the anisotropic properties of the single-walled carbon nanotubes (SWNTs) as it becomes less difficult to transform the SWNTs into an aligned configuration when they are confined in a small diameter fiber. This helps to take fuller advantage of the high mechanical properties of the SWNT materials in the axial direction. However, in creating nanocomposite fiber systems, the issues of dispersion and nanotube−matrix interaction and adhesion become of utmost importance when improved mechanical properties are anticipated. In addressing these issues in this work it has been found that sidewall chemical functionalization can be an effective tool for improving both the dispersion and interaction between the nanotube and the matrix. This work evaluates the effect of sidewall functional groups on fluorinated single-walled carbon nanotubes (F-SWNTs) as a precursor for improved interfacial adhesion in a...
The Shape from Motion Approach to Rapid and Precise Force/Torque Sensor Calibration

We present a new technique for multi-axis force/torque sensor calibration called shape from motion. The novel aspect of this technique is that it does not require explicit knowledge of the redundant applied load vectors, yet it retains the noise rejection of a highly redundant data set and the rigor of least squares. The result is a much faster, slightly more accurate calibration procedure. A constant-magnitude force (produced by a mass in a gravity field) is randomly moved through the sensing space while raw data is continuously gathered. Using only the raw sensor signals, the motion of the force vector (the motion) and the calibration matrix (the shape) are simultaneously extracted by singular value decomposition. We have applied this technique to several types offorce/torque sensors and present experimental results for a 2-DOF fingertip and a 6-DOF wrist sensor with comparisons to the standard least squares approach.
Silicone Hydrophobicity and Oleophilicity

Polydimethylsiloxane (PDMS), the most familiar silicone polymer, is a very water repellent material. Its hydrophobicity is not markedly less than many fluorine containing polymers. The original purpose of introducing fluorine into silicones in the form of polymethyltrifluoropropylsiloxane (PMTFPS) was not to seek enhanced water repellency but to provide improved resistance to organic oils and solvents. Because of the two methyl groups on each silicon atom in PDMS, the resultant oleophilicity is a considerable drawback in applications involving exposure to hydrocarbon fluids and oils. In this article we survey the contact angles with water and n-hexadecane of these polymers and related, more highly fluorinated fluorosilicones, being the simplest measure of their hydrophobicity and oleophilicity, respectively. These contact angle values provide quantitative insight into commercially valuable aspects of silicone surface science.