cssi/SciSciGPT-SciSciNet huggingface dataset:
Proceedings of the 2009 MidSouth Computational Biology and Bioinformatics Society (MCBIOS) Conference

MCBIOS 2009 was held February 20–21, 2009 at the Hunter Henry Center in Starkville, Mississippi on the Mississippi State University campus. The conference was hosted by the four research universities in Mississippi comprising the Mississippi Computational Biology Consortium – Jackson State University (JSU), Mississippi State University (MSU), the University of Mississippi (UM), and the University of Southern Mississippi (USM). Dr. Dawn Wilkins of UM and Dr. Susan Bridges of MSU served as conference co-chairs. Keynote speakers were Dr. Laura Elnitski, Head of the Genomic Functional Analysis Section at the National Human Genome Research Institute (NHGRI), Howard Cash, President and CEO of Gene Codes Corporation, and Dr. Cathy Wu, Director of the Protein Information Resource (PIR). Dr. Raphael Isokpehi of JSU organized a panel discussion entitled Careers in Computational Biology and Bioinformatics: Perspective from Employers and Students. Panelists were Dr. Ed Perkins of the U.S. Army Engineering Research and Development Center, Robert Cottingham of Oak Ridge National Laboratory (ORNL), Dr. Doris M. Kupfer, Federal Aviation Administration, James C. Fuscoe, FDA National Center for Toxicological Research, and Cynthia Jeffries, student intern at ORNL. Over 40 student and faculty attendees also participated in the Speed Networking event organized by Dr. Isokpehi and featured in a recent Science Careers article [1]. Each person in the event spent 3 minutes talking to twenty other participants in the two hour session providing students an opportunity to interact with employers and with students from other universities in the region. Dr. Bindu Nanduri and Dr. Andy Perkins, both of MSU managed the setup, judging, and scoring of 80 posters. Monetary awards were provided by Dr. Ed Perkins. Student poster award winners were: first place – Eric Morales of the University of New Orleans (UNO), second place Teresia Buza of MSU, third place – Prashanti Manda of MSU and honorable mention to Amanda Alba of the UNO, Surya Saha of MSU and Sudhir Chowbina of the Indiana University School of Informatics. Student winners for oral presentations were: first place – Enis Afgan of the University of Alabama at Birmingham, second place – Lipi R. Archarya of UNO, and third place – Anastasia Chueva of Mississippi Valley State University.
N glycosylation of the virus binding domain is not essential for function of the human poliovirus receptor.

Abstract The human poliovirus receptor (hPVR) is a glycoprotein with three immunoglobulin-like extracellular domains, of which the N-terminal domain (V-type domain) is necessary and sufficient for virus binding and uptake. The effect of N glycosylation of the V domain of hPVR on binding and entry of poliovirus was studied. Stable mouse L-cell lines were generated that express PVR-specific cDNA. One of the cell lines expressed a mutant of hPVR, in which both asparagine residues of the two N-glycosylation sites of the V domain were changed to aspartate (N105D) and serine (N120S), respectively. In the second mutant cell line, the portion of the cDNA encoding the V domain of hPVR was substituted by the homologous sequence of the recently isolated PVR cDNA from monkey cells. This V domain naturally lacks both N glycosylation sites and encodes D105 and S120 at the respective positions of the open reading frame. Absence of N glycosylation at these sites was demonstrated by in vitro translation of the two mutant coding sequences in the presence of microsomal membranes. Both PVR mutant cell lines were capable of poliovirus binding and replication. However, binding of anti-PVR monoclonal antibody D171 and protection from viral replication by this antibody were observed only with the glycosylation mutant carrying the human V domain. In contrast, infection of the cell line expressing the monkey-human hybrid receptor was not blocked even though monkey cells are fully protected by monoclonal antibody D171. The data suggest that N glycosylation of the V domain of hPVR is not essential for viral replication in human tissues and that differential glycosylation of hPVR at these sites is likely not a determinant of viral tissue tropism. Furthermore, the virus binding site and the epitope recognized by monoclonal antibody D171 do not appear to overlap.
The 2006 Retrovirology Prize: call for nominations

Retrovirology announces a nomination call for its 2006 prize to recognize an outstanding mid-career retrovirologist. The 2005 Retrovirology prize was awarded to Dr. Stephen P. Goff.
The Effect of Weld Gas Flow Rate on Al-Li Weldability

Adequate shield and plasma gas flow rate during plasma arc welding are crucial factors in achieving high quality welds. Too low a shield gas flow rate lets atmosphere enter into the arc and too high a rate wastes weld gas and may cause turbulence and entrain atmosphere. Sufficient plasma gas flow is required for keyhole welding and, as shown in this paper, can reduce hydrogen contamination in the weld. In-situ optical spectroscopy used to detect oxygen and hydrogen in the welding arc during variable polarity plasma arc (VPPA) welding of aluminum 2090 revealed that there is an easily detected critical shield gas flow rate needed to exclude atmosphere and that this critical rate can be used to automatically control gas flow rates during welding.
Perceived mental workload and operator performance of dexterous manipulators under time delay with master-slave interfaces

Robotic manipulators that use joystick interfaces for telemanipulation take time and effort to master and lack an intuitive basis for human robot interaction. These factors can hamper operator performance, increase cognitive workload, and limit overall user effectiveness on highly dexterous tasks. Master-slave interfaces (MSIs) used in the fields of animatronics, telesurgery, and hazardous materials handling are intuitive and improve operator performance, but are limited because they typically operate in a controlled environment and lack robustness. When Master Slave (MS) controllers use forcefeedback errors can accumulate and create instabilities due to the synchronous bilateral communication between the remote and local systems. Instability can be mitigated and errors reduced in these systems by separating the bilateral communication into a dual-unilateral (DU) asynchronous communication. This research focused on comparing and analyzing current MSI controllers with a new DU control method that reduces or eliminates MSI issues such as latency, error, and information loss while providing the user with accurate forcefeedback capability and transparency during operation. It used a simulation-based approach to determine which selected MSI controllers provide users with robust control of dexterous manipulators under time delay. Users performed a variety of dexterous force-feedback tasks with different controllers and the study measured objective task performance and completion time success along with cognitive workload related to user perceived task interaction and mental demands through subjective ratings on the NASA (National Aeronautics and Space Administration) Task Load Index (TLX). The research findings will help to develop MSI controllers designed to provide operators robust and intuitive interfaces for low-level control of dexterous manipulators.
Metabolism of d-Arabinose: a New Pathway in Escherichia coli

Several growth characteristics of Escherichia coli K-12 suggest that growth on l-fucose results in the synthesis of all the enzymes necessary for growth on d-arabinose. Conversely, when a mutant of E. coli is grown on d-arabinose, all of the enzymes necessary for immediate growth on l-fucose are present. Three enzymes of the l-fucose pathway in E. coli, l-fucose isomerase, l-fuculokinase, and l-fuculose-l-phosphate aldolase possess activity on d-arabinose, d-ribulose, and d-ribulose-l-phosphate, respectively. The products of the aldolase, with d-ribulose-l-phosphate as substrate, are dihydroxyacetone phosphate and glycolaldehyde. l-Fucose, but not d-arabinose, is capable of inducing these activities in wild-type E. coli. In mutants capable of utilizing d-arabinose as sole source of carbon and energy, these activities are induced in the presence of d-arabinose and in the presence of l-fucose. Mutants unable to utilize l-fucose, selected from strains capable of growth on d-arabinose, are found to have lost the ability to grow on d-arabinose. Enzymatic analysis of cell-free extracts, prepared from cultures of these mutants, reveals that a deficiency in any of the l-fucose pathway enzymes results in the loss of ability to utilize d-arabinose. Thus, the pathway of d-arabinose catabolism in E. coli K-12 is believed to be: d-arabinose ⇌ d-ribulose → d-ribulose-l-phosphate ⇌ dihydroxyacetone phosphate plus glycolaldehyde. Evidence is presented which suggests that the glycolaldehyde is further oxidized to glycolate.
Molecular Resonance Phenomena

Resonant scattering theory has been developed over more than fifty years. Its application in molecular physics began in earnest in 19621 although there were earlier treatments of predissociation,2 dissociative recombination3 and electron attachment4 that contained some elements of the theory. There are two features of the theory as applied in atomic and molecular physics that are not so important in other fields. Firstly, since the non-relativistic Hamiltonian is known, one should be able to calculate the resonance parameters, such as the position and width, from first principles and not treat them solely as empirical parameters. Secondly, in studies of molecular resonant states one would like to incorporate the Born-Oppenheimer separation of electronic and nuclear motion into the definition of the resonances and the computational algorithms.
Competition in the Financial Services Sector: A Case of Kenyan Annuities Market

Competition in the financial services sector influences information, allocation and cost efficiency. The annuity market segment of insurance companies is particularly important as it is characterized by “entry and permanent lock in” of consumers to the firms thus creating permanent contractual claims. This study examines the annuity industry in Kenya using the Structure Conduct Performance (SCP) paradigm and sought to determine the market concentration, provide a behavioral explanation of how firms acquire and sustain market power and establish how the concentration affects conduct and performance of the annuity providers in Kenya. A mixed design is applied where secondary data is collected from the 8 firms offering annuity products in Kenya between 2009 and 2011. Focus group discussions are then conducted with key industry informants to explain the results. Market concentration is measured using the concentration ratio (C4) and the Herfindahl-Hirschman Index (HHI). An SCP model for the annuity market segment is then conceptualized. The findings point to a highly concentrated industry with HHI indices averaging 98% in the three years to 2011. Evidence generated shows that market power in the market is enabled by regulation, irreversible long term nature of the products, collusion between pension administrators and the players, lack of close substitutes to annuities and absence of differentiation – factors which have led to tendency for mergers and strategic partnerships, low returns for the annuitants, information asymmetry, low bargaining power of the consumers, diseconomies of scale and lack of innovation. The study recommends some policy implications to minimize the abuse of dominant positions by firms.
Moses and Civilization: The Meaning behind Freud's Myth

Moses and Civilization: The Meaning behind Freud's Myth. Robert A. Paul. New Haven, CT: Yale University Press, 1996.268 pp.
Ethanol, sedative hypnotics, and glutamate receptor function in brain and cultured cells

Ethanol, acutely, is a potent and selective inhibitor of the function of theN-methyl-d-aspartate (NMDA) subtype of glutamate receptor in primary cultures of cerebellar granule cells. The effect of ethanol can be reversed by high concentrations of glycine, and nonequilibrium ligand binding studies in brain membrane preparations suggest that ethanol may act by decreasing the frequency of ion channel opening. After chronic consumption of ethanol by animals, the number of NMDA receptors (measured by ligand binding) is increased in many brain areas. Similarly, NMDA receptor function is increased in cerebellar granule cells exposed chronically to ethanol. In the intact animal, this receptor up-regulation may be associated with ethanol withdrawal seizures, which are attenuated by uncompetitive antagonists at the NMDA receptor. In contrast to ethanol, barbiturates have a greater inhibitory effect at the kainate subtype of glutamate receptor than at the NMDA receptor. After chronic barbiturate ingestion, kainate binding isdecreased in certain brain areas, while ligand binding to the NMDA receptor is increased. Overall, the pattern of brain area-specific effects of barbiturates on NMDA and kainate receptor function is quite distinct from that of ethanol.
Ab Initio Studies of Coupled Electron Transfer/Proton Transfer in CytochromecOxidase

The coupled electron/proton transfer mechanism of cytochrome c oxidase is investigated using ab initio electronic structure theory. We predict the location and identity of the Fe and Cu ligands in the oxidized (O), partially reduced (E), and fully reduced (R) forms of the enzyme. Our calculations suggest that a tyrosine residue in close proximity to the active site is deprotonated during the enzymatic cycle. These predictions are consistent with experimental evidence and provide a molecular explanation for both the observed antiferromagnetic coupling of Fe3+ and Cu2+ and the distinction between “fast” and “slow” forms of the oxidized enzyme.
Microstructure and tribology of carbon, nitrogen, and oxygen implanted ferrous materials

Abstract Nitrogen, carbon, and oxygen ions have been implanted into ferrous materials under unusual conditions of elevated temperatures and very high dose rates. The tribological durabilities of the resulting surfaces are examined with a special type of pin-on-disc wear test apparatus and found in most cases to be dramatically improved compared to surfaces prepared with conventional implantation conditions. Near-surface microstructures and compositions are characterized after implantation and after wear testing by backscatter Mossbauer spectroscopy, X-ray diffraction, scanning electron microscopy, and Auger electron spectroscopy. These data provide evidence for the predominant mechanisms responsible for the observed sliding wear behavior induced by each of the three species.
Mechanisms of ovarian steroid regulation of norepinephrine receptor-mediated signal transduction in the hypothalamus: implications for female reproductive physiology.

In many mammalian species, the ovarian steroid hormones estradiol (E(2)) and progesterone (P) act in the hypothalamus and preoptic area to coordinate the timing of female sexual receptivity with ovulation. We study lordosis behavior, an important component of sexual receptivity in rats, and its regulation by E(2) and P as a model system for understanding how hormonal modulation of synaptic neurotransmission influences reproductive physiology and behavior. Our findings suggest that E(2) and P extensively regulate synaptic communication involving the catecholamine norepinephrine (NE) in the hypothalamus. Estrogen priming shifts the balance of postsynaptic NE receptor signaling in the hypothalamus and preoptic area away from beta-adrenergic activation of cAMP synthesis toward alpha(1)-adrenergic signaling pathways. Attenuation of beta-adrenergic signal transduction is achieved by receptor-G-protein uncoupling, apparently due to stable receptor phosphorylation. E(2) modification of alpha(1)-adrenergic signaling includes both increased expression of the alpha(1B)-adrenoceptor subtype and a dramatic, P-induced reconfiguration of the biochemical responses initiated by agonist activation of alpha(1)-adrenoceptors. Among these is the emergence of alpha(1)-adrenergic receptor coupling to cGMP synthesis. We also present evidence that estrogen promotes novel, functional interactions between insulin-like growth factor-1 (IGF-1) and alpha(1)-adrenergic receptor signaling in the hypothalamus and preoptic area. Thus, estrogen amplification of signaling mediated by alpha(1)-adrenoceptors is multifaceted, involving changes in gene expression (of the alpha(1B)-adrenoceptor), switching of receptor linkage to previously inactive intracellular pathways, and the promotion of cross talk between IGF-1 and NE receptors. We propose that this hormone-dependent remodeling of hypothalamic responses to NE maximizes reproductive success by coordinating the timing of the preovulatory release of gonadotropins with the period of behavioral receptivity in female rodents.
Rat serum promotes the in vitro development of mouse blastocysts during early somitic stages of embryogenesis

Mouse blastocysts cultured in vitro in rat serum develop through the early somitic stages of embryogenesis at the same rate as embryos cultured in human cord serum. Rat serum can thus be used instead of human cord serum for in vitro culturing of mouse embryos.
Effect of Doppler spread in OFDM-based UWB systems

Orthogonal frequency division multiplexing (OFDM) can be used in ultrawideband (UWB) communications to deal with delay spread of UWB channels. Relative motion between transmitter, receiver, and scattering environment induces Doppler spread. Since Doppler shift is proportional to subcarrier frequency, the time-selective fading is subcarrier dependent. In a narrowband (NB) system, this dependence is negligible, and all subcarriers are subjected to the same time-selective fading. However, in a UWB system, different subcarriers will experience different fading. In this paper, intercarrier interference (ICI) caused by the relative motion between transmitter and receiver in OFDM-based UWB communications is investigated. An exact expression as well as bounds is derived for the degradation of performance measured by signal-to-interference ratio (SIR). A design example is given to illustrate the concepts developed in the paper.
A theory of flavor mixing

Abstract We investigate the origin of the Cabibbo angle and other flavor-mixing angles in an ambidextrous SU(2)L × SU(2)R × U(1) gauge theory of weak and electromagnetic interactions involving 2n quark flavors. We show how a discrete symmetry of the Lagrangian leads to flavor-diagonal weak currents where all flavor-mixing angles vanish. Each quark is assigned a position on the “clock of flavor” and the charged-current weak interactions are identified as nearest-flavor couplings. Soft breakdown of the discrete symmetry leads to a one-parameter family of flavor-mixing angles in the charged weak currents. All angles are expressed in terms of this parameter and quark mass ratios. The neutral currents remain flavor diagonal. Upper and lower bounds on 2n, the number of flavors, are obtained by constraining the theory to fit what is known from experiment. Departures from Cabibbo universality become intolerable if 2n 12. We conclude that the number of flavors must be 8, 10, or 12. We construct a more ambitious theory in which the Cabibbo angle and its analogs are O(α) calculable radiative corrections. For reasonable values of the quark mass ratios, we fail to obtain a Cabibbo angle of the right order of magnitude. Our theory involves an equal number of lepton flavors and quark flavors. A large number of flavors is required if neutrinos are to be sufficiently light. We explore the case of 2n = 12, and find a novel mechanism for the neutrino induction of trimuon events.
Synthesis and mechanical response of disordered colloidal micropillars.

We present a new approach for studying the uniaxial compressive behavior of colloidal micropillars as a function of the initial defect population, pillar and colloid dimension, and particle–particle interaction. Pillars composed of nanometer scale particles develop cracks during drying, while pillars composed of micron scale particles dry crack-free. We subject the free-standing pillars, with diameters of 580 μm and 900 μm, to uniaxial compression experiments using a custom-built micromechanical testing apparatus. In pillars with pre-existing cracks, compression activates the macroscopic defects, leading to fracture and stochastic mechanical response as a result of the flaw distribution. Pillars that dry crack-free fail by shear bands that initiate near the punch face. While macroscopically identical, pillar-to-pillar mechanical response varies significantly. We attribute the disparate response to varying structure and environmental conditions. To isolate the effects of environment, we performed controlled experiments over a range of relative humidity levels ( 98% RH). The level of atmospheric humidity affects particle–particle cohesion and friction, resulting in dramatically different mechanical responses. We discuss the results in the context of underlying particle rearrangements leading to mesoscopic shear localization and examine comparisons with atomic disordered systems such as metallic glasses.
Combined zero-quantum and spin-diffusion mixing for efficient homonuclear correlation spectroscopy under fast MAS: broadband recoupling and detection of long-range correlations

Fast magic angle spinning (MAS) NMR spectroscopy is emerging as an essential analytical and structural biology technique. Large resolution and sensitivity enhancements observed under fast MAS conditions enable structural and dynamics analysis of challenging systems, such as large macromolecular assemblies and isotopically dilute samples, using only a fraction of material required for conventional experiments. Homonuclear dipolar-based correlation spectroscopy constitutes a centerpiece in the MAS NMR methodological toolbox, and is used essentially in every biological and organic system for deriving resonance assignments and distance restraints information necessary for structural analysis. Under fast MAS conditions (rotation frequencies above 35–40 kHz), dipolar-based techniques that yield multi-bond correlations and non-trivial distance information are ineffective and suffer from low polarization transfer efficiency. To overcome this limitation, we have developed a family of experiments, CORD–RFDR. These experiments exploit the advantages of both zero-quantum RFDR and spin-diffusion based CORD methods, and exhibit highly efficient and broadband dipolar recoupling across the entire spectrum, for both short-range and long-range correlations. We have verified the performance of the CORD–RFDR sequences experimentally on a U-13C,15N-MLF tripeptide and by numerical simulations. We demonstrate applications of 2D CORD–RFDR correlation spectroscopy in dynein light chain LC8 and HIV-1 CA tubular assemblies. In the CORD–RFDR spectra of LC8 acquired at the MAS frequency of 40 kHz, many new intra- and inter-residue correlations are detected, which were not observed with conventional dipolar recoupling sequences. At a moderate MAS frequency of 14 kHz, the CORD–RFDR experiment exhibits excellent performance as well, as demonstrated in the HIV-1 CA tubular assemblies. Taken together, the results indicate that CORD–RFDR experiment is beneficial in a broad range of conditions, including both high and moderate MAS frequencies and magnetic fields.
Splicing pathways of SV40 mRNAs in X. laevis oocytes differ in their requirements for snRNPs.

Abstract To examine the role of small nuclear ribonucleoproteins (snRNPs) in mRNA splicing, we have injected SV40 DNA, in the presence or absence of anti-Sm or anti-(U1)RNP antibodies, into the nucleus of X. laevis oocytes, and analyzed the viral specific RNAs and proteins that were synthesized. In the absence of antibodies, the majority of the viral mRNAs were spliced, giving rise to transcripts and proteins analogous to those found in infected monkey cells. However, the relative efficiencies with which the various splice sites were utilized were different in the two cell types. When sera from systemic lupus erythematosus (SLE) patients containing anti-Sm or anti-(U1)RNP antibodies were coinjected with the viral DNA, splicing of L-strand-specific (late) mRNA was dramatically inhibited. Cleavage at both 5′ and 3′ splice sites was blocked, leading to an accumulation of unspliced primary transcripts. Neither the total amount of late RNA synthesized nor the formation of mature polyadenylated late mRNA 3′ ends was affected. These results indicate that U1 snRNPs play a crucial role in mRNA splicing in vivo. Unexpectedly, the effects of the sera on E-strand-specific (early) viral mRNA splicing were different. All anti-Sm or -(U1)RNP sera tested had no detectable effect on the splicing of the mRNA coding for the small tumor antigen. A subset of these sera, however, inhibited large tumor antigen mRNA splicing. On the basis of these data it is suggested that different pre-mRNAs, or even different splice sites within the same pre-mRNA, have dissimilar interactions with snRNP particles in the splicing reaction.
Ab initio step and kink formation energies on Pb(111)

Ab-initio formation energies for (100)- and (111)-microfacet steps on Pb(111) are in satisfactory agreement with measured values, given that these values are known only as well as the Pb(111) surface energy; the calculated step-energy ratio, 1.29, is within {approximately}8% of experiment. In contrast, calculated kink-formation energies, 41 and 60 meV for the two step types, are 40--50% below published experimental values derived from STM images. The discrepancy results from interpreting the images with a step-stiffness vs. kink-energy relation appropriate to (100) but not (111) surfaces. Good agreement is found when the step-stiffness data are reinterpreted, taking proper account of the trigonal symmetry of Pb(111).
The St. Vincent (Lesser Antilles) herpetofauna: Conservation concerns

The Lesser Antillean island of St. Vincent harbors 18 species of terrestrial amphibians and reptiles: four frogs (including the endemic Pristimantis shrevei ), one turtle, ten lizards (including endemic Anolis griseus and A. trinitatis ), and three snakes (including endemic Corallus cookii and Chironius vincenti ). In addition, four species of marine turtles are known from the region. Ecological relationships of an introduced frog ( E. johnstonei ) and an introduced lizard ( A. sagrei ) should be monitored in order to evaluate any potentially negative impact on endemic congeners. Two endangered endemic species ( P. shrevei and C. vincenti ) may benefit from sympatry with the endemic parrot, Amazona guildingii , the national bird of St. Vincent, with which they share high-quality upland forest habitat. Like other West Indian herpetofaunas, that on St. Vincent faces threats that include dramatic habitat alterations, introduced predators (mongooses, domestic cats) and competitors (e.g., A. sagrei ), changes in the prey base, and the potential introduction of the chytrid fungus. These threats can best be addressed by development and implementation of effective management programs based on ecological studies by local and foreign biologists.
Isocyanate-functionalized latexes: Film formation and tensile properties

Latexes functionalized with isocyanate groups were prepared by carrying out the emulsion terpolymerization of dimethyl meta-isopropenyl benzyl isocyanate (TMI®) with methyl methacrylate and n-butyl acrylate. The film formation of these latexes and the tensile properties of the resulting latex films were studied. The effect of TMI concentration on the film properties was investigated. The locus of the isocyanate groups in the latex particles was controlled by using different polymerization processes. The locus of the functional groups was found to greatly influence the tensile properties of the latex films. Triethyl amine was used as an external catalyst to cure the TMI polymer films. One-component self-curable systems capable of undergoing crosslinking at ambient temperatures were developed by incorporating small amounts of methacrylic acid into the recipe. These systems exhibited significant improvement in tensile properties upon curing. In addition, the shelf-stability of these latexes was found to be excellent. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1869–1884, 1997
Dynamics of Barrier Crossing in Classical Nucleation Theory

The dynamics of nucleation barrier crossing is examined using Becker-Doring kinetics, matrix methods, and stochastic model simulation. Fundamental connections between resistance to crossing and fluctuations in cluster size are derived using the Kubo-Nyquist relations. For analysis of nucleation kinetics, the matrix approach of Shugard and Reiss is supplemented with a novel extension based on recursion/projection operator methods. The combined approach yields nested sequences of upper and lower bounds to the relaxation rates of clusters coupled to a thermal bath. Fluctuations are studied using simulations based on a stochastic model of cluster evaporation/growth. Under typical conditions, it is found that relaxation from the top of the barrier is slow, due to multiple re-crossings, and the transmission coefficient for nucleation is small and extremely difficult to estimate from single-cluster simulations using standard Bennett -Chandler and Kramers models. A new approach based on relaxation on a “dual” potential surface is introduced. It is shown that the dual model provides an optimal weighted cluster sampling and reliable estimation of the transmission coefficient (to within a few percent). Collectively, these methods address the efficient determination of nucleation rates from computer simulations of individual cluster evaporation/growth events.
Report of progress on accelerometer for recording earthquake‐shocks

In the summer of 1930 the Civil Engineering Department of the Massachusetts Institute of Technology undertook to design and construct an accelerometer capable of recording an earthquake-shock at a point comparatively near the epicenter. Mills W. Braunlich was appointed Research Associate in the Department to carry out this project. The instrument is essentially a torsion-pendulum, the “inertia-mass” being mounted eccentrically on a taut wire similar to that used in the Wood-Anderson seismometer. The particular form of the inertia-mass is that suggested by Dr. Frank Wenner of the Bureau of Standards. It consists of a rectangular metal loop about 1 inch by 3/8 inch, the longer side being attached to the supporting wire, which is 4 inches in length. The free-period is one twenty-fifth of a second. That side of the loop which is farthest from the torsion-wire is made of sheet copper one-hundredth of an inch thick, bent into a curve so that it can vibrate between the poles of a magnet. The air-gap is one thirty-second of an inch. In the experimental instrument an electromagnet was used in order to permit variations in the damping-action; this will be replaced later by a permanent magnet. In addition to the magnetic damping, it was found necessary to use special damping to reduce lateral (“violin-string”) vibrations of the wire. This was accomplished by placing bits of felt, soaked in oil, just above and just below the inertia-mass.
Histologic and receptor analysis of primary and secondary vestibulodynia and controls: a prospective study.

Objective The objective of the study was to assess the association between hormone receptor densities, pain nerves, and inflammation in vestibulodynia patients. Study Design In a prospective study, tender and nontender biopsies from 10 primary and 10 secondary vestibulodynia patients were compared with biopsies in 4 nontender controls. Hormone receptors were evaluated using immunohistochemistry for estrogen receptor-α and -β, androgen, and progesterone receptors. Inflammation, nerves, and mast cells were assessed histologically. Statistical analysis was by Fisher's exact test, analysis of variance, paired Student t test, and Wilcoxon rank test. Results Tender sites from primary vestibulodynia had increased nerve density compared with secondary and control biopsies ( P = .01). Tender sites in secondary vestibulodynia had more lymphocytes than tender primary sites and control biopsies ( P Conclusion Markers of inflammation differed between primary and secondary vestibulodynia and controls.
Synthesis of 1,4-disubstituted (E,Z)-1,3-dienes from lithium dicyclohexyl(trans-1-alkenyl)(1-alkynyl)borates

Treatment of lithium dicyclohexyl(trans-1-alkenyl)(1-alkynyl)borates with either boron trifluoride etherate or tri-n-butyltin chloride results in the preferential migration of the alkenyl group from boron to the adjacent alkynyl carbon atom. Protonolysis of the resultant organoboron intermediates with acetic acid affords the corresponding 1,4-disubstituted (E,Z)-1,3-dienes in good yields, provided that the (Z)-alkenyl moiety of the diene does not contain a tertiary alkyl group. Demonstration that this novel procedure is applicable for the preparation of (E,Z)-1,3-dienes containing functional groups has been shown by the synthesis in 66% yield of methyl (10E, 12Z)-hexadecadienoate, a precursor via lithium aluminium hydride reduction of the sex pheromone of the female silk moth, Bombyx mori.
Disability and juvenile delinquency: issues and trends

The US juvenile justice system has gone through many changes since its inception in the late 1890s. Even with these changes and more than 100 years of empirical research, there is a paucity of literature published on juvenile delinquents with disabilities. The present article focuses on juvenile delinquents with disabilities, addressing definitional issues, prevalence and incidence data, types of educational and mental health services available, and future directions for research.
Large-scale geophysical reconstruction of man-made ground at former industrial iron-furnace plantations

Blast-iron-furnace plantations were widespread throughout colonial and postcolonial America and therefore represent sites of specific archaeological interest. Because such plantations often were a really extensive, historical reconstruction of a site is challenging using conventional archaeological field techniques alone. Therefore, we appraise the usefulness of integrating magnetic gradiometer, electrical-resistivity tomography (ERT), and electromagnetic (EM31) data in detecting and delineating buried structures related to former operation of the Shade furnace, a typical industrial plantation in 19th-century Pennsylvania. The geophysical results were ground-truthed in seven locations by archaeological excavation. Geophysical results demonstrated that (1) the distribution of remaining original soils could be mapped; (2) waste materials (e.g., slag, used brick, burned charcoal, iron ore, and broken-up sandstone or limestone) within or above the original soils could be detected and delineated, whether the material occurred in pits or lenses or was dispersed across the ground surface; and (3) the location and spatial extent of many former structures related to furnace operation could be identified, such as building or bridge foundations and casting-related structures (e.g., the tapping channel or the casting floor, and the former courses of a water canal (raceway) and a supply road). We conclude that geophysical techniques can play a key role in reconstructing man-made ground at former industrial furnace sites in North America.
A characterization for the negative welfare effects of cost reduction in Cournot oligopoly

Abstract This paper characterizes the welfare effects of cost reductions in a Cournot model with linear costs. Under linear demand, a small reduction in a firm’s marginal cost reduces welfare if and only if its market share is less than 1/(2n+2), or equivalently, its marginal cost exceeds a critical level determined by the market. A large cost reduction by the firm increases welfare if and only if its magnitude is at least twice the difference between the current marginal cost and its critical value. The paper also extends the results to non-linear demand, but the characterizations become less tractable.
Integrating product and process design with optimal control: A case study of solvent recycling

Abstract This paper proposes the simultaneous integration of environmentally benign solvent selection (product design), solvent recycling (process design) and optimal control for the separation of azeotropic systems using batch distillation. The previous work performed by Kim et al. (2004. Entrainer selection and solvent recycling in complex batch distillation. Chemical Engineering Communications 191(12), 1606–1633) combines the chemical synthesis and process synthesis under uncertainty. For batch distillation, optimal operation is also important due to the unsteady state nature of the process and high operating costs. Optimal control allows us to optimize the column operating policy by selecting a trajectory for the reflux ratio. However, there are time-dependent uncertainties in thermodynamic models of batch distillation due to the assumption of constant relative volatility. In this paper, the uncertainties in relative volatility were modeled using Ito processes and the stochastic optimal control problem was solved by combined maximum principle and non-linear programming (NLP) techniques. Then the previous work of optimal solvent selection and recycling was coupled with optimal control. As a real world example for this integrated approach, a waste stream containing acetonitrile–water was studied. The optimal design parameters obtained by Kim et al. (2004. Entrainer selection and solvent recycling in complex batch distillation. Chemical Engineering Communications 191(12), 1606–1633), for this separation were used and the optimal control policy is computed first without considering uncertainties by variable transformation technique. The deterministic optimal control policy improves the product yield by 4.0% as compared to the base case, verified using a rigorous simulator for batch distillation. When the stochastic optimal control policy was computed representing the relative volatility as an Ito process, a similar recovery rate was obtained from simulations, but the batch time was reduced significantly, producing the most profitable operation.
Remaking Beijing: Tiananmen Square and the Creation of a Political Space – By Wu Hung.

The article reviews the book "Remaking Beijing: Tiananmen Square and the Creation of a Political Space," by Wu Hung.
The placement of central venous catheters in infants with cardiac shunts: safety measures and false alarms.

ENTRAL VENOUS CATHETERS (CVCs) are integral tools for hemodynamic monitoring and adminis~:ration of cardiovascular drugs and fluids in pediatric patients undergoing repair of congenital heart defects. However, placement of CVCs in young infants can be technically difficult and may lead to complications, including accidental arterial cannulation, hematoma, Homer's syndrome, pneumothorax, injury of the thoracic duct, and cerebral air embolism resulting from a right-to-left shunt. For effective safe care, it is important to promptly differentiate signs of genuine complications from those due to congenital anatomic defects. A case is presented in which bright red blood re;~arn was noted after an otherwise uneventful central venous catheterization, and in which rapid confirmation of accurate central venous access prevented repeated puncture attempts and the increased risk of complications.
Psychiatric symptoms in disliked medical patients.

Twenty-two patients seen in a clinic for systemic lupus erythematosus were tested for organicity, depression, anxiety, and hostility. Four of the clinic's physicians ranked these patients from most liked to least liked. In three of the four physicians, dislike was significantly correlated with the patient's degree of organicity. Ten of the patients were ranked among the three most disliked patients by one or more of the ranking physicians. This group of most disliked patients contained all patients with signs of organic brain damage and all suicidal patients. Dislike of a patient by the physician may be a clue to serious psychiatric impairment. ( JAMA 241:1117-1120, 1979)
The functions of the HQ unit in the multibusiness firm

The basic functions of the corporate headquarters (HQ) multibusiness firms are both entrepreneurial (value-creation) and administrative (loss prevention). The development and implementation of these HQ functions reflect the industries in which the firms operate. Historically, the ability of the headquarters to carry out these functions has determined both the successful paths to growth for a multibusiness enterprise and the limits to that growth.
Synthesis and characterization of cytochrome P-450 epoxygenase metabolites of eicosapentaenoic acid

Eicosapentaenoic acid, a major component of fish oil extracts, was recently shown to be metabolized to vicinal diol regioisomers by renal and hepatic cytochrome P-450 epoxygenases. The diol products were also found in the urine of people ingesting fish oil. In the present report, we developed a chemical method of making milligram amounts of the epoxide intermediates and their diol products. Eicosapentaenoic acid was reacted with 0.1 eq.m-chloroperoxybenzoic acid for 15 min. After normal- and reverse-phase high performance liquid chromatography plus capillary gas chromatography and electron impact mass spectrometry, the products were identified as 17,18-cis-epoxyeicosa-5,8,11,14-tetraenoic, 14,15-cis-epoxy-eicosa-5,8,11,17-tetraenoic, 11,12-cis-epoxy-eicosa-5,8,14,17-tetraenoic, 8,9-cis-epoxy-eicosa-5,11,14,17-tetraenoic and 5,6-cis-epoxy-eicosa-8,11,14,17-tetraenoic acids. The total epoxide yield from eicosapentaenoate was 10% per incubation. By reincubating (cycling) the unused substrate 10–20 times, the total epoxide yield could be increased to 66–88%. Epoxide regioisomers were not produced in equal amounts; epoxygenation was facilitated as the distance between the target double bond and carbomethoxy group increased. Upon hydrolyzing the epoxides, the gas-chromatographic retention times and mass spectra of the diol products were found to match those of biological metabolites. In addition, each of these standards was rapidly and quantitatively synthesized in an amount (milligram) adequate for biological tests.
Behavior therapy and the experimental analysis of behavior: contributions of the science of human behavior and radical behavioral philosophy.

Abstract It has been argued that clinical psychologists, including clinical behavior therapists, are not aware of or knowledge about advances being made in basic behavioral research (Marks, Behavioral Psychotherapy), 9, 137–154, 1981). The present paper addresses the arguments advanced by clinical and experimental psychologists that behavior therapy and cognitve–behavior therapy are moving away from their respective ties to the experimental operant laboratory. It is argued that there are many areas of mutual interest between basic behavioral and clinical research and application. Several major research programs of operant psychology are analyzed in order to demonstrate conclusively that advances in basic behavioral studies have relevance for application by clinical psychologists. Progress in the experimental fields of the quantitative law of effect (the matching law), operant/classical interactions, including behavioral momentum, modeling and verbal and rule-governed behavior are analyzed. Applications of these basic behavioral principles to clinical settings are also illustrated. It is concluded that the experimental analysis of behavior can add much to the continuing development of a scientifically-based clinical psychology, and that mutual interest research on both sub-disciplines of psychology will lead to a greater understanding of the causes and conditions of human behavior, as well as direct the ability of clinical psychologists to effect meaningful behavioral change.
The impact of vendor records on cataloging and access in academic libraries

The addition of low-quality vendor records to the bibliographic utilities (OCLC and RLIN) has had a significant impact on cataloging and access in academic libraries. Vendor records are brief, non-standard bibliographic records created by booksellers and loaded into the utilities. Because many libraries are choosing to copy these records from the utilities to their local online catalogs without editing or enhancing them, much effort is being duplicated, as individual libraries make the same enhancements locally. Less original cataloging is being conducted in the languages represented by the vendor records, and more upgrading of lower-quality records is now necessary, a change that has affected cataloging workflows, and ultimately access, in academic libraries. Quantitative research is needed on the impact of vendor records.
Evidence for sequence scrambling in collision-induced dissociation of y-type fragment ions.

Sequence scrambling from y-type fragment ions has not been previously reported. In a study designed to probe structural variations among b-type fragment ions, it was noted that y fragment ions might also yield sequence-scrambled ions. In this study, we examined the possibility and extent of sequence-scrambled fragment ion generation from collision-induced dissociation (CID) of y-type ions from four peptides (all containing basic residues near the C-terminus) including: AAAAHAA-NH2 (where “A” denotes carbon thirteen (13C1) isotope on the alanine carbonyl group), des-acetylated-α-melanocyte (SYSMEHFRWGKPV-NH2), angiotensin II antipeptide (EGVYVHPV), and glu-fibrinopeptide b (EGVNDNEEGFFSAR). We investigated fragmentation patterns of 32 y-type fragment ions, including y fragment ions with different charge states (+1 to +3) and sizes (3 to 12 amino acids). Sequence-scrambled fragment ions were observed from ~50 % (16 out of 32) of the studied y-type ions. However, observed sequence-scrambled ions had low relative intensities from ~0.1 % to a maximum of ~12 %. We present and discuss potential mechanisms for generation of sequence-scrambled fragment ions. To the best of our knowledge, results on y fragment dissociation presented here provide the first experimental evidence for generation of sequence-scrambled fragments from CID of y ions through intermediate cyclic “b-type” ions.
Comparison study of SnO2 thin- and thick-film gas sensors

Polycrystalline SnO2 thin films were prepared at 600°C by metal organic chemical vapor deposition (MOCVD) technique using tetraethyltin as an organometallic (OM) source and UHP O2 as oxidant. The films were analyzed by means of XRD, SEM, and AES for their microstructure characterization and subjected to H2 and CO gas detection. The results were compared to SnO2 thick-films derived from metal organic decomposition (MOD) in order to study differences in gas sensing characteristics in relation to the microstructure. The microstructure of the MOCVD-derived thin films was fully dense columnar structure with rough surface morphology while that of the MOD-derived thick films was porous structure resulting from loosely interconnected small crystallites. Both types of sensors showed good reproducibility and stability toward 1% H2 gas with an enhancement of the sensitivity and the time response in the thick-film sensor. The sensing characteristics were degraded under 1% CO gas for both types of films.