cssi/SciSciGPT-SciSciNet huggingface dataset:
DNA-Damaging Enediyne C-1027 Inhibits Initiation of Intracellular SV40 DNA Replication in trans†

This study used 2-D agarose gel techniques to examine the effects of the DNA-strand scission enediyne C-1027 on DNA replication in SV40-infected BSC-1 cells. Replication of SV40 DNA was inhibited by C-1027 to a greater extent than was BSC-1 genomic DNA replication in infected cells. Low nanomolar concentrations (0.2-10 nM) of C-1027 affected a rapid, progressive decrease in SV40 replication activity and replication intermediates (RIs) within 15 min after drug addition. A concurrent decrease in the signal of both the SV40 bubble arc and replication activity with increasing concentrations of C-1027 suggested that C-1027 inhibited initiation of new RIs. Additionally, the reduction in bubble arc signal observed with C-1027 was prevented when elongation of nascent chains was blocked by aphidicolin. Thus, the C-1027-induced disappearance of RIs probably is related to the maturation of preformed replication molecules in the absence of initiation of new RIs. Strand damage to SV40 DNA was barely detectable at concentrations where inhibition of replication activity was nearly complete, indicating that C-1027 replication inhibition occurs in trans.
Will terrorists turn to poison

M any analysts consider chemical and biological weapons to be of limited military utility, in part because countermeasures exist to keep down battlefield casualties. Chemical weapons can produce high numbers of casualties when used against an unprotected civilian population, however. For example, Iraqi chemical attacks against the city of Halabja, a northern Iraqi Kurdish village held by Iran during the Iran-Iraq war, killed between 3,000 and 5,000 people. But history suggests killing civilians on this scale does not win wars between states. What chemical and biological weapons can do is capture the worlds attention and create fear among possible victims. Saddam’s mere threat to use chemical weapons during the 1991 Gulf War caused thousands of citizens to evacuate Tel Aviv and Jerusalem, despite strong doubts that Iraq’s extendedrange, reduced-payload Scuds could be used effectively to disseminate a chemical agent. With this capacity to fascinate and frighten, poisons may be ideally suited for terrorists, for whom creating fear in the target population is more important than creating casualties per se. To date, however, terrorists have used chemical and biological weapons rarely, and only to injure or kill small numbers of people. What constraints have held terrorists back? And are those constraints eroding?
"I always assumed that I wasn't really that close to [her]": Reasoning about Invisible Algorithms in News Feeds

Our daily digital life is full of algorithmically selected content such as social media feeds, recommendations and personalized search results. These algorithms have great power to shape users' experiences, yet users are often unaware of their presence. Whether it is useful to give users insight into these algorithms' existence or functionality and how such insight might affect their experience are open questions. To address them, we conducted a user study with 40 Facebook users to examine their perceptions of the Facebook News Feed curation algorithm. Surprisingly, more than half of the participants (62.5%) were not aware of the News Feed curation algorithm's existence at all. Initial reactions for these previously unaware participants were surprise and anger. We developed a system, FeedVis, to reveal the difference between the algorithmically curated and an unadulterated News Feed to users, and used it to study how users perceive this difference. Participants were most upset when close friends and family were not shown in their feeds. We also found participants often attributed missing stories to their friends' decisions to exclude them rather than to Facebook News Feed algorithm. By the end of the study, however, participants were mostly satisfied with the content on their feeds. Following up with participants two to six months after the study, we found that for most, satisfaction levels remained similar before and after becoming aware of the algorithm's presence, however, algorithmic awareness led to more active engagement with Facebook and bolstered overall feelings of control on the site.
MAJOR INVESTMENT STUDIES AND ENVIRONMENTAL DOCUMENTATION: CLEARING UP THE CONFUSION

Federal planning regulations issued in 1993 require major investment studies (MISs) to help metropolitan planning organizations reach decisions on high-cost, high-impact highway and transit facilities. The regulations offer two options for the development of National Environmental Policy Act (NEPA) documents for major investments. In Option 1, draft and final NEPA documents are prepared during the project development/ preliminary engineering phase for any projects that emerge from an MIS and have been incorporated into the region's long-range plan. In Option 2, a draft NEPA document is prepared as part of the MIS. Although there is general appreciation and understanding of the planning principles underlying the MIS process, the role of environmental impact analysis and documentation has been a source of confusion, misunderstanding, and skepticism. An attempt is made to clear up this confusion by explaining Option 1, Option 2, and the more recently conceived Option 11/2 and by presenting situations and cir...
The effect of chronic oral nicotine administration on fetal weight and placental amino acid accumulation in mice.

Nicotine was administered to female mice by addition to the drinking water at concentrations up to 100 μg/ml. The animals were given the solutions for at least 2 weeks before breeding and throughout gestation. The fetuses and placentas from all animals were examined on the 17th day of gestation. Fetuses of the nicotine-treated mice weighed up to 12% less than controls. There was no reduction in the litter size in the treated animals. Placental mince was incubated in vitro to measure the ability of the tissue to accumulate the neutral amino acid, α-aminoisobutyric acid. Placentas from animals receiving nicotine, 100 μg/ml in the drinking water, or by ip injection, 1.3 mg/kg, had a decreased intracellular amino acid concentration measured at 60 min. Determinations of placental fluid parameters indicated that this decrease was not due to an effect on intracellular space. Animals receiving 100 μg/ml nicotine in the drinking water had a decrease in mean placental weight compared to control. Nicotine treatment had no effect on the placental concentrations of acetylcholine or the activities of acetylcholinesterase or acetyltransferase. The results of this investigation demonstrate that nicotine is able to decrease fetal weight and depress placental amino acid transport in mice as it does in humans.
Shift dynamics and control of dual-clutch transmissions

Shifts in a dual-clutch transmission (DCT) are realized by torque transfer from one clutch to another without traction interruption due to the controlled slippage of the clutches. The timing of engagement and disengagement of the two clutches is critical for achieving a smooth shift without engine flare and clutch tie-up. This paper presents an analytical model for the simulation, analysis and control of shift dynamics for DCT vehicles. A dynamic model and the control logic for the integrated vehicle have been developed using Matlab/Simulink as the simulation platform. The model has been used to study the variation in output torque in response to different clutch pressure profiles during shifts. Optimized clutch pressure profiles have been created for the best possible shift quality based on model simulation. As a numerical example, the model is used for a DCT vehicle to simulate the wide-open throttle performance. Vehicle launch and shift process are both simulated to assess transmission shift quality and validate the effectiveness of the shift control.
Profiles of the Sources of Science Self-Efficacy.

Abstract The purpose of this study was to investigate (a) the latent profiles that arise from middle and high school students' ( N = 1225) reported exposure to information from the four hypothesized sources of self-efficacy; (b) the relationships between these latent profiles and science self-efficacy and science achievement; and (c) the differences in latent profiles as a function of implicit theory of science ability, gender, and grade level. Results revealed that a four-class solution fit the data the best. Results support past findings indicating that mastery experiences are a powerful source of self-efficacy. Furthermore, there seemed to be an additive benefit of drawing from multiple sources simultaneously. Gender did not predict membership in these four profiles, but implicit theory of ability and grade level did. The results show that students in the most adaptive profiles drew from multiple sources of efficacy-relevant information and espoused a strong belief in the plasticity of their science abilities, whereas those who were in the least adaptive profiles exhibited a high degree of negative affect and held a fixed view of science ability.
Determination of appropriate dynamic slack sequencing rules for an industrial flow shop via discrete simulation

This paper presents an application of combined discrete and network simulation modelling to determine and validate an appropriate sequencing technique for a modified flow shop. The research was based upon a study of a modified flow shop at the International Business Machines, Federal Systems Division (IBM/FSD), Manassas, Virginia, manufacturing Facility. The company's concerns were directed towards enhancing the real-time scheduling of a man and machine dependent flow shop where meeting customer due dates was vital. In this manufacturing facility it is necessary to rework all parts that do not initially meet stringent quality control specifications until those parts do meet those quality limits. Therefore another reason for analyzing different sequencing rules was the necessity to better control the rework activity.The sequencing technique currently used at this facility is based on Earliest Due Date scheduling. With the cooperation of the production control organization at IBM/FSD, Manassas, a simulation study was performed in order to determine if an enhancement to the current system could be found. The objective of the research was to determine which due date based sequencing technique would best meet the overriding production control criteria of the IBM/FSD flow shop. The company's production control objectives were to minimize number of tardy jobs, total amount of job tardiness, and total amount of in--process inventory.The flow shop was modelled using SLAM simulation language. The flow shop was both machine and man dependent requiring both entities to be modelled. A time-consuming task encountered in the development of this model, and with the development of many other simulation models which attempt to represent real world systems, was the task of obtaining data in the proper format to analytically determine the control parameters for the model. This paper presents and discusses some of the difficulties encountered with the data interpretation.Also included in the paper is a discussion of the due date based sequencing techniques studied and the usefulness of simulation to determine and validate the appropriate sequencing technique.
Getting work done on the web: supporting transactional queries

Many searches on the web have a transactional intent. We argue that pages satisfying transactional needs can be distinguished from the more common pages that have some information and links, but cannot be used to execute a transaction. Based on this hypothesis, we provide a recipe for constructing a transaction annotator. By constructing an annotator with one corpus and then demonstrating its classification performance on another,we establish its robustness. Finally, we show experimentally that a search procedure that exploits such pre-annotation greatly outperforms traditional search for retrieving transactional pages.
Backbone Trace of Partitivirus Capsid Protein from Electron Cryomicroscopy and Homology Modeling

Most dsRNA viruses have a genome-enclosing capsid that comprises 120 copies of a single coat protein (CP). These 120 CP subunits are arranged as asymmetrical dimers that surround the icosahedral fivefold axes, forming pentamers of dimers that are thought to be assembly intermediates. This scheme is violated, however, in recent structures of two dsRNA viruses, a fungal virus from family Partitiviridae and a rabbit virus from family Picobirnaviridae, both of which have 120 CP subunits organized as dimers of quasisymmetrical dimers. In this study, we report the CP backbone trace of a second fungal partitivirus, determined in this case by electron cryomicroscopy and homology modeling. This virus also exhibits quasisymmetrical CP dimers that are connected by prominent surface arches and stabilized by domain swapping between the two CP subunits. The CP fold is dominated by α-helices, although β-strands mediate several important contacts. A dimer-of-dimers assembly intermediate is again implicated. The disordered N-terminal tail of each CP subunit protrudes into the particle interior and likely interacts with the genome during packaging and/or transcription. These results broaden our understanding of conserved and variable aspects of partitivirus structure and reflect the growing use of electron cryomicroscopy for atomic modeling of protein folds.
Integrin signaling and matrix assembly.

Cell adhesion and migration are controlled by the level of Α5Β1 integrin (fibronectin receptor) and by the amount of fibronectin matrix around the cell; adhesion is promoted at all levels of integrin expression and matrix assembly, whereas high levels of either or both curb cell migration. The Α5Β1 integrin appears to be a growth-suppressing integrin, and it protects cells from apoptosis when growth factors are absent. In contrast, the ΑvΒ3 integrin (vitronectin receptor) cooperates with certain growth factors, potentiating their effect on cells. These effects of Α5Β1 and ΑvΒ3 depend on signaling pathways specific for these integrins; integrins have both common and specific pathways for signaling into the cell. Moreover, integrins require activation from the inside of the cell to be able to bind their ligand outside the cell. High Α5Β1 expression and abundant matrix formation also suppress tumorigenicity in vivo, whereas perturbing the function of Α5Β1 with peptides that block its ligand binding suppresses experimental metastasis. Effecting these changes in tumor cells by gene therapy or pharmacological approaches may provide useful new cancer therapies.
Children's Friendships: Shifts Over a Half-Century in Perspectives on Their Development and Their Effects

Provocative ideas about the nature, development, and effects of children's friendships were included in the lectures of Harry Stack Sullivan, which were edited and published in the 1950s. Sullivan emphasized the love, intimacy, and collaboration found in the close friendships that children form around 8 to 10 years of age. Later research has shown that close friendships have both a positive dimension, with features such as intimacy, and a negative dimension, with features such as rivalry. However, close friendships do not emerge suddenly at 8 to 10 years of age. Rather, the closeness of children's friendships increases gradually during middle childhood and adolescence. Recent studies suggest that having close, high-quality friendships increases children's success in the peer social world. Having high-quality friendships could magnify the positive or negative influence of friends with positive or negative characteristics, but this hypothesis needs to be evaluated more thoroughly in the future.
THE INFLUENCE OF TIMING IN EXPLORATORY PROTOTYPING AND OTHER ACTIVITIES IN DESIGN PROJECTS

ABSTRACT The importance of prototyping in the design process has been widely recognized, but less research emphasis has been placed on the appropriate timing and detail of so-called "throwaway" prototyping during the preliminary design phase. Based on a study of mid-career professional graduate students, statistically significant correlations were found between the time such prototypes were created and design outcome. Building prototypes early on in the design process, or performing additional rounds of benchmarking and user interaction later on during the project (in addition to the typical early stage efforts), correlated with better design outcome, although the total time spent on these activities did not. The correlation between project presentations and reviewer scores are also touched upon. These findings suggest that the timing of design activities is more important than the time spent on them. INTRODUCTION It is widely recognized that decisions made in the early [9]stages of the design process have great bearing on the outcome of the design in terms of design success, cost of manufacturing and time to market. The later in the design process problems are identified and changes made to the design, the more costly it becomes [1-3]. The question then is, how should designers go about exploring the design space in the most efficient way possible, find a desirable design direction, and execute a successful design? on effective ways to conduct different design activities This research examines the timing of prototyping related activities in the early stages of the design process. Research has been conducted on prototyping in the early stages of the design process, with some arguing for early and frequent prototyping as a way to test ideas early [4, 5] and to help build confidence in design concepts in a team [6]. There are several different design activities that have been recognized as important to design outcome and have been widely researched. These range from prototyping and sketching to benchmarking and collecting input from end-users. Prototyping is often thought of in terms of the particular technology or materials involved in creating the prototype, such as 3D printing or aluminum stock. This paper considers prototypes from a different perspective, that of as an artifact that design teams use to evaluate potential design concepts before further development [7, 8]. These early stage prototypes are created with the express understanding that they will be discarded after evaluation, and are thus "throwaway" prototypes. Using this strategy encourages building the "cheapest" prototype that can still provide needed information, meaning that such prototypes may be made of relatively inexpensive materials and are fast to fabricate. This approach to fabrication has been expressed as "fail early to succeed sooner,"popularized by the design firm IDEO and has been widely cited as a strategy for early stage design[4].Although there has been a significant amount of research
Resonance states from poles of the relativistic S-matrix

A state vector description for relativistic resonances is derived from the first order pole of the jth partial S-matrix at the invariant square mass value in the second sheet of the Riemann energy surface. To associate a ket, called Gamow vector, to the pole, we use the generalized eigenvectors of the four-velocity operators in place of the customary momentum eigenkets of Wigner, and we replace the conventional Hilbert space assumptions for the in- and out-scattering states with the new hypothesis that in- and out-states are described by two different Hardy spaces with complementary analyticity properties. The Gamow vectors have the following properties: (i) They are simultaneous generalized eigenvectors of the four velocity operators with real eigenvalues and of the self-adjoint invariant mass operator M =(Pμ Pμ)1/2 with complex eigenvalue . (ii) They have a Breit–Wigner distribution in the invariant square mass variable and lead to an exactly exponential law for the decay rates and probabilities.
Characterization and solubilization of an acyl chain elongation system in microsomes of leek epidermal cells

Abstract Microsomes prepared from leek epidermal tissue readily elongate stearoyl-CoA to very long chain fatty acid with malonyl-CoA as the C 2 unit. In the absence of stearoyl-CoA, but in the presence of ATP, microsomes elongate endogenous free fatty acids. Endogenous CoA is the source of CoA. Palmitoyl, stearoyl, and higher saturated acyl-CoAs are readily elongated by the microsomal system but oleoyl-CoA is ineffective; however, the higher monounsaturated acyl-CoAs can be elongated. Since the very long chain fatty acids of the leek epidermis are all saturated, it would appear that the reaction controlling the nature of the final acyl product is the inactivity of oleoyl-CoA as a substrate. There is no evidence that acyl carrier protein participates in the elongation reactions. Evidence is also presented suggesting that (a) there may be two elongation systems, one responsible for the conversion of stearoyl-CoA to arachidoyl-CoA and the second involved in the conversion of arachidoyl-CoA to very long chain fatty acids, and that (b) the elongation activities may be associated with a large polypeptide.
Differential expression of ribosomal L31, Zis, gas-5 and mitochondrial mRNAs following oxidant induction of proliferative vascular smooth muscle cell phenotypes.

Treatment of cultured vascular smooth muscle cells (vSMCs) with benzo(a)pyrene (BaP), a prooxidant present in the particulate phase of tobacco smoke, induces highly proliferative (i.e. atherogenic) phenotypes. Critical early target genes in vSMCs have been identified, but patterns of gene expression following repeated cycles of carcinogen treatment in vivo have yet to be evaluated. In the present study, male Sprague-Dawley rats (175-200 g) were given weekly injections of BaP (10 mg/kg) for 8 weeks to induce atherogenic phenotypes. At the end of this atherogenic regimen, vSMCs were established in serial culture and monitored for patterns of proliferative activity and gene expression. vSMCs isolated from BaP-treated animals (hence forth referred to as BaP cells) exhibited constitutively increased growth rates, and marked enhancement of proliferation in response to serum mitogens. Differential display polymerase chain reaction (DD-PCR) and Northern blot analyses revealed that mRNAs for ribosomal protein L31 and Zis genes were suppressed, while gas-5 and mitochondrial mRNAs were overexpressed in BaP cells relative to control mRNA populations. In situ hybridization experiments in vascular tissue confirmed these alterations in vivo. This is the first report linking expression of these genes to proliferative dysregulation during the course of experimentally-induced atherogenesis.
Atomic hydrogen as a launch vehicle propellant

An analysis of several atomic hydrogen launch vehicles was conducted. A discussion of the facilities and the technologies that would be needed for these vehicles is also presented. The Gross Liftoff Weights (GLOW) for two systems were estimated; their specific impulses (I sub sp) were 750 and 1500 lb(sub f)/s/lb(sub m). The atomic hydrogen launch vehicles were also compared to the currently planned Advanced Launch System design concepts. Very significant GLOW reductions of 52 to 58 percent are possible over the Advanced Launch System designs. Applying atomic hydrogen propellants to upper stages was also considered. Very high I(sub sp) (greater than 750 lb(sub f)/s/lb(sub m)) is needed to enable a mass savings over advanced oxygen/hydrogen propulsion. Associated with the potential benefits of high I(sub sp) atomic hydrogen are several challenging problems. Very high magnetic fields are required to maintain the atomic hydrogen in a solid hydrogen matrix. The magnetic field strength was estimated to be 30 kilogauss (3 Tesla). Also the storage temperature of the propellant is 4 K. This very low temperature will require a large refrigeration facility for the launch vehicle. The design considerations for a very high recombination rate for the propellant are also discussed. A recombination rate of 210 cm/s is predicted for atomic hydrogen. This high recombination rate can produce very high acceleration for the launch vehicle. Unique insulation or segmentation to inhibit the propellant may be needed to reduce its recombination rate.
The neurosteroid, 3α-androstanediol, prevents inhibitory avoidance deficits and pyknotic cells in the granule layer of the dentate gyrus induced by adrenalectomy in rats

Testosterone (T), dihydrotestosterone (DHT), 3alpha-diol (5alpha-androstane-3alpha,17beta-diol), or vehicle was administered daily to gonadectomized, adrenalectomized male Long-Evans rats. Four days after adrenalectomy (ADX), animals were tested for inhibitory avoidance. Vehicle-treated rats had shorter latencies than 3alpha-diol-treated rats and non-corticosterone-depleted rats. All three androgens significantly reduced the number of pyknotic cells in corticosterone-depleted rats. Neurosteroids may mediate androgens' functional and morphological neuroprotective effects.
Exploring skewed parton distributions with two-body models on the light front: Bimodality

We explore skewed parton distributions for simple, model wave functions in a truncated two-body Fock space. Consideration of non-Gaussian wave functions is our main emphasis, from which we observe the distributions are bimodal (there can be two distinct peaks) in the Fock-space diagonal overlap region $(xg\ensuremath{\xi}).$ We demonstrate that this behavior arises from convoluting two light-front wave functions to form the skewed parton distribution. Furthermore, the factorization Ans\"atze, which have been used often, are shown not to hold. At high |t|, we can write the skewed parton distribution in terms of quark distribution amplitudes and perturbative wave functions thereby providing new tests.
Global systems dynamics and policy: Lessons from the distant past

Many human societies on Earth have at times experienced what we would call a ‘crisis’. In the case of simple societies, in a wide range of environments throughout history, such crises have manifested themselves as famines. In complex societies, they may have taken the form of economic depressions such we are currently experiencing, social conflicts or wars of some kind between groups, or even the collapse of complete empires such as the Roman and the Chinese Empires (cf. Tainter, 1988). The recurrence of this phenomenon, at a wide range of scales from small bands to complete empires, and in virtually any environment or domain of human endeavor raises the question whether such crises are inherent in the socio-environmental dynamics of all human societies? And if that is the case, would comparative studies of a number of instances reveal to us what drives societies into such ‘crises’? The study of crises has led to many descriptive publications, case studies and doomsday hypotheses, from Gibbon (1776–1789) and Spengler (1918–1922) to Diamond (2005), but it is only in recent years that elements of a more general scientific theory of socio-environmental dynamics, including ‘societal crises’ or even ‘societal collapse’ are emerging, combining insights from four research domains. The natural sciences have contributed to the set of ideas that is sometimes called ‘the science (or theory) of complex systems’ (e.g. Prigogine, 1978; Kauffman, 1993; Bak, 1996; Levin, 1999; Mitchell, 2009). Social anthropology has contributed in the area of ‘Cultural Theory’ (Thompson, Ellis, & Wildavsky, 1990), and the sciences of organization and information have contributed to our understanding of the organization dynamics of social structures (e.g. Pattee, 1973; Simon, 1969; Huberman, 1988; White, 2001). Some of these ideas on the nature of organizations have been taken up and adapted by ecologists (e.g. Allen & Starr, 1982; O’Neill et al., 1986; Allen & Hoekstra, 1992). Finally, the first attempt at a synthesis of these different ideas comes from a collaborative effort of ecologists and social scientists (Gunderson & Holling, 2002; Holling, 2001; Walker & Salt, 2006).
French restitution, German compensation: Algerian Jews and Vichy's financial legacy

Post-World War II German reparative measures had originally been created for the benefit of European Jews. The April 2004 official German compensation programme for Jews who were interned in World War II included reparations to Algerians Jews of North Africa who were involved in a history of German indemnification superimposed upon a prior history of French restitution. Post-war German reparations since 1952 continue to be rooted in ongoing vibrant debates about coming to terms with Germany's Nazi past. In contrast, France's attitudes and policies towards the Vichy past in France and Algeria foreclosed its financial responsibility to Algerian Jews (or for that matter Algerian Muslims) for what Frantz Fanon would call a ‘just reparation’ for the crimes of colonialism. Consequently, the case of Algerian Jewry and what happened to the community from the beginning of World War II through Algeria's 1962 independence, and into the era of their settlement en masse in France (where they received reparations as Pi...
Light Scattering from Long Thin Glass Cylinders at Oblique Incidence

The angular distribution of the light scattered by long, thin glass cylinders was measured at both perpendicular and oblique incidence using a newly designed light-scattering photometer; these results were compared with theoretical calculations. Each set of data could be fit uniquely to a calculated result corresponding to a particular size parameter. The size parameters thus obtained for the same fiber at two wavelengths and several tilt angles agreed with each other.
Ideal flushing agents for integrated optical acoustic imaging systems

An increased number of integrated optical acoustic intravascular imaging systems have been researched and hold great hope for accurate diagnosing of vulnerable plaques and for guiding atherosclerosis treatment. However, in any intravascular environment, vascular lumen is filled with blood, which is a high-scattering source for optical and high frequency ultrasound signals. Blood must be flushed away to make images clear. To our knowledge, no research has been performed to find the ideal flushing agent that works for both optical and acoustic imaging techniques. We selected three solutions, mannitol, dextran and iohexol, as flushing agents because of their image-enhancing effects and low toxicities. Quantitative testing of these flushing agents was performed in a closed loop circulation model and in vivo on rabbits.
Fluids Confined in Porous Materials: Towards a Unified Understanding of Thermodynamics and Dynamics

A recently developed theoretical approach to understand the relaxation processes for fluids confined in mesoporous materials, especially in adsorption/desorption from bulk gases, is discussed. The theory is based on a lattice gas formulation of the molecular interactions in the system and is referred to as dynamic mean field theory. The theory has the important property that the limiting behavior at long times is consistent with the results from mean field theory (or density functional theory) for the model. In this sense it provides a unified picture of thermodynamics and relaxation dynamics for the system. Two illustrative applications are presented. The first is to the dynamics of capillary condensation in a finite length slit pore in contact with a bulk gas. The second application is to the dynamics of cavitation during desorption from an inkbottle pore in contact with the bulk gas. The outlook for future developments and applications of the approach is also discussed.
Production rate changes in a ternary two-recycle process

Recent studies of a ternary process with the reaction A + B → C and two recycle streams have revealed some interesting dynamic problems in transitioning from one production rate to another, even though the new production rate is attainable from a steady-state point of view. If the process has been designed with a small reactor volume, which means large recycle flow rates, the process sometimes shuts itself down when the production rate is increased. The control structure used has fixed reflux flow rates on both columns. The basic problem is a buildup of impurity (component C) in one or both of the recycle streams. This can be prevented by modifying the control structure to use reflux-to-feed ratios for processes with intermediate reactor holdups or to use dual composition control on both columns for processes with low reactor holdups.
Photophysics of novel conjugated polymers with alternating heteroaromatic rings: synthesis and applications

We report the design, syntheses, structure-property relationships, and applications of alternating copolymers containing heteroaromatic rings. Polymers with different structures were synthesized by Suzuki couplings of 1,4-phenyldiboronic acid with various dibromoarenes. The effect of heteroatoms was studied by comparing polymers containing biphenyl, bipyridine, bithiazole, or thienyl moieties. The changes in the polymer structure led to changes in singlet and triplet energies, absorption and emission properties, as well as energy transfer parameters. The effect of polymer structure on absorption maxima, emission properties, excimer formation, aggregate formation, as well as singlet and triplet energies were studied. Alternating copolymers of bipyridyl moieties gave rise to blue-emitting polymers with emission maxima at 410nm, where as the use of bithiazole moieties red-shifted the emission. All of these polymers can be used in polymer light-emitting devices as the emitting layers, where thienyl containing polymers can be used as hole transport layers. The polymers transferred energy efficiently to Coumarins and europium complexes, allowing for their potential use in longer wavelength emitting applications. The ability of bipyridine containing polymers for use as metal ion sensors was studied.
Responses of two hymenopteran predators to surface Chemistry of their prey: Significance for an alkaloid-sequestering caterpillar.

Larvae ofUresiphita reversalis (Guenee) (Lepidoptera: Pyralidae) sequester quinolizidine alkaloids from their leguminous hosts and store them primarily in the cuticle. Stored alkaloids are lost with the last larval molt. Extracts of late-instar larvae and of pupae were applied to larvae of the potato tuber moth,Phthorimaea operculella (Zeller) (Gelichiidae), which are normally palatable to two hymenopteran predators, the Argentine ant,Iridomyrmex humilis (Mayr) (Formicidae), and the paper wasp,Mischocyttarus flavitarsus (Sauss.) (Vespidae). Larvae ofP. operculella treated with alkaloid extracts ofU. reversalis larval exuviae, or with surface extracts of whole larvae, were deterrent to both predators, compared to untreated prey. Extracts of pupal exuviae added toP. operculella, however, were not deterrent.P. operculella larvae treated with the authentic alkaloids sparteine and cytisine were also deterrent to these hymenopteran predators. Storage of small but concentrated amounts of plant secondary compounds in the cuticle appears to be an efficacious means of defense against at least two common predators of lepidopteran larvae.
A transmutation approach to underwater sound propagation

Abstract A hybrid approach is used to combine analytical computations that model the major features of the ocean with symbolic and numerical computations that model the secondary features. Integral operators are used to transmute solutions of the Helmholtz equation with constant coefficients into solutions of the Helmholtz equation with variable coefficients. The kernels of these operators satisfy certain hyperbolic partial differential equations and characteristics conditions. The transmutations preserve some, but not all, of the boundary conditions given for the Helmholtz equation.
Work in progress — Soft skills within a project — Based approach: A Multimedia Engineering degree

We are introducing a new and complete set of methodologies based on a real project-based approach. Our Multimedia Engineering students work within interdisciplinary groups “simulating” several industrial specific roles in order to solve actual problems for real clients with concrete environmental parameters. In addition to all of these, we are focusing on all the required soft skills and competences, both specific and generic, within the Multimedia Engineering product lifecycle.
Reaction of organoaluminium species with bidentate phosphine ligands. Synthesis and molecular structure of [AlCl3][(Ph2P)2CH2][AlCl2(CH3)] and [AlCl3]2[(Ph2P(O))2CH2]

Abstract Reaction of methylaluminium sesquichloride with bis(diphenylphosphino) methane and bis(diphenylphosphinoyl)methane affords [AlCl3][(Ph2P)2CH2][AlCl2(CH3)] (I) and [AlCl3]2[(Ph2P(O))2CH2] (II), respectively. Compound I crystallizes in the triclinic space group P−1 with unit cell parameters a = 10.009(3), b = 10.748(4), c = 14.806(5) A, α = 90.38(3), β = 103.36(2), γ = 96.89(3)°, V = 1537.5 A3 and ϱ = 1.36 for Z = 2. Compound II crystallizes in the monoclinic space group C2 with unit cell parameters a = 12.773(2), b = 13.028(3), c = 9.461(2) A, β = 104.43(2)°, V = 1524.60 A3 and ϱ = 1.49 for Z = 2. Full-matrix least-squares refinement based on 3034 observed reflections for I converged at R = 0.047 (Rw = 0.066); full-matrix least-squares refinement based on 1565 observed reflections for II converged at R = 0.043 (Rw = 0.050). Both products result from reaction of the disproportionation products of methylaluminium sesquichloride, AlCl3 and AlCl2(CH3).
MACHINED SURFACE ERROR ANALYSIS — A FACE MILLING APPROACH

In the automotive industry, sealing quality between two flat joint surfaces is directly affected by the surface flatness. To know how much flatness is caused by machining operations, a traditional trial-and-error method has been used. The prediction for machined surface error/distortion can help to assess the integrity of the structural design as well as develop fixturing scheme to optimize machining quality. In this paper, a finite element method is applied to extract the compliance matrix of milling surface of a workpiece, such as the cylinder deck face, and an encoding MatLab program is used to compute the flatness due to milling forces. The paper focuses on deriving analytical models for evaluating the flatness of the cylinder deck face and optimizing the manufacturing process. Some special considerations have been taken to manufacturing cutting force evaluations according to analysis results of the deck face flatness. Emphasis is also placed on the optimization of machining parameters by iterations of flatness results so that minimization of surface deformations under machining loads can be achieved. The methodology introduced in the paper is the closed-loop iteration by combining structural finite element analysis (FEA) simulation, tooling kinematic simulation, and MatLab data modeling.
Virtual Rheoscopic Fluid for Large Dynamics Visualization

Visualizations of fluid hydraulics often use some combination of isosurfacing and streamlines to identify flow features. Such algorithms show surface features well, but nearby features and internal features can be difficult to see. However, virtual rheoscopic fluids (VRF) provide a physically-based visualization that can be analyzed like physical rheoscopic fluid and can show nearby and internal features. Whereas previous VRF implementations were custom serial implementations that could not scale to large dynamics problems, these visualizations demonstrate our scalable VRF algorithm operating on large fluid dynamics data. Our algorithm is implemented in VisIt and the movies were generated on TACC's Longhorn machine using 128 nodes (1024 cores).
On some applications of the Magnus expansion in nuclear magnetic resonance

Abstract In this paper, the Magnus expansion for the exponent of the development operator of a time-dependent Hamiltonian is applied to some cases in nuclear-magnetic-resonence spin dynamics. We analyze (i) “rotating frame” NMR decay and consider, in particular, the experiment of Lee and Goldburg for both a single-crystal and polycrystalline sample (ii) NMR decay in a rotating sample (single crystal and polycrystal), and (iii) the multiple pulse echo experiment of Ostroff and Waugh and of Mansfield and Ware. All these examples may be analyzed in terms of responses to well-defined time-dependent Hamiltonians. Our calculations are in good qualitative and quantitative agreement with experimental observations when such are available.
Prolactin-brain interactions in the induction of maternal behavior in rats

Most adult female mammals display an immediate onset of maternal care toward their offspring at parturition, whereas the responses of inexperienced, nulliparous females are often less intense or absent. The shift from being a slow or nonresponder in nulliparous females to a rapid responder at parturition in primiparous animals is induced in part by the endocrine changes of pregnancy. This report reviews recent evidence demonstrating a role for prolactin in the stimulation of maternal behavior in the rat. Moreover, new findings are presented that indicate that endogenous rat prolactin acts centrally to stimulate maternal behavior in steroid-primed, nulliparous rats and that the ventromedial hypothalamus in addition to the medial preoptic area are important neural substrates regulating the rapid induction of maternal behavior at parturition.
Elementary Bialgebra Properties of Group Rings and Enveloping Rings: An Introduction to Hopf Algebras

This is a slight extension of an expository paper I wrote a while ago as a supplement to my joint work with Declan Quinn on Burnside's theorem for Hopf algebras. It was never published, but may still be of interest to students and beginning researchers. Let K be a field, and let A be an algebra over K. Then the tensor product A ⊗ A = A ⊗ K A is also a K-algebra, and it is quite possible that there exists an algebra homomorphism Δ: A → A ⊗ A. Such a map Δ is called a comultiplication, and the seemingly innocuous assumption on its existence provides A with a good deal of additional structure. For example, using Δ, one can define a tensor product on the collection of A-modules, and when A and Δ satisfy some rather mild axioms, then A is called a bialgebra. Classical examples of bialgebras include group rings K[G] and Lie algebra enveloping rings U(L). Indeed, most of this paper is devoted to a relatively self-contained study of some elementary bialgebra properties of these examples. Furthermore, Δ determines...
Performance monitors for multi-programming systems

This paper proposes a scheme for improving the throughput of multi-programming systems. The basis of the proposal is the collection of a suitable set of measures of total system performance as well as corresponding per-process measures. Two types of control over system performances are suggested: (1) dynamic tuning of allocation policies to reflect the total system load, and (2) adjustment of the mix of processes competing for system resources in such a way as to keep the system within the range over which its allocation policies function properly.This work was supported in part by the Advanced Research Projects Agency at the Office of the Secretary of Defense (F 44620-67-C-0058) and is maintained by the Air Force Office of Scientific Research. Reproduction in whole or in part is permitted for any purpose of the United States Government.
Teaching anatomy with surgeons' tools: Use of the laparoscope in clinical anatomy

The purpose of this study was to establish the feasibility of laparoscopy in embalmed cadavers to teach abdominal gross anatomy. One cadaver was selected based on body habitus and absence of previous abdominal operations. A standard trocar was used to enter the abdomen at the umbilicus. Two trocars were placed in the left upper quadrant. Pneumoperitoneum was achieved with continuous CO(2) pressure. Liver retraction was achieved percutaneously, exposing the porta hepatis and the gallbladder. The dissection was done with four first-year medical students using standard laparoscopic equipment. Following this, the demonstration was projected over multiple monitors so that all students could participate. Laparoscopic dissection in an embalmed cadaver is feasible and an excellent educational tool for both the medical student and the dissector. The dissector has the opportunity to manipulate laparoscopic tools in a human model closely paralleling operative experience, and the students have an opportunity to learn abdominal anatomy from a clinical perspective. Laparoscopic examination and dissection of fresh cadavers has been used for training surgeons on new procedures such as colon resection, antireflux procedures, and cholecystectomy. There is no report of this same technology used in embalmed cadavers to teach basic anatomy. This approach allows first-year medical students to learn the anatomy while exposing them to the technology currently used in surgical practice, and it affords surgical residents and students additional opportunities to practice laparoscopic skills.
Percutaneous arterial access: Redefining the possibilities using suture-mediated closure (PercloseTM)

The standard for achieving post-procedure arteriotomy hemostasis has been 15-minute manual compression followed by 4- to 8-hour bed rest. Inadequate hemostasis can lead to local complications such as hematomas or significant complications requiring surgical intervention. Suture-mediated closure of the femoral arteriotomy offers an alternative to the standard manual compression to achieve secure hemostasis and has decreased overall access complications. Because the tissue is brought into complete apposition, the closure is independent of clot formation and the average time to hemostasis is significantly reduced. This article will discuss suture-mediated closure, the appropriate selection of patients and developing the proper technique for deployment. Using suture-mediated closure will allow for a greater scope of eligible patients, no significant increase and often a decrease in complications, greater patient comfort and throughput, and utilization benefits for the practice of interventional radiology.
Delayed esophageal perforation after pneumatic dilatation for the treatment of achalasia.

Two cases of delayed esophageal perforation following a pneumatic dilatation for the treatment of achalasia are presented. Esophagrams obtained immediately after pneumatic dilatation failed to reveal a perforation. Increasing symptoms prompted repeat contrast studies, at which time an esophageal perforation was demonstrated. The occurrence of delayed esophageal perforation after pneumatic instrumentation is emphasized. An ischemic etiology for this delayed perforation is postulated.
Assessing Local Impacts: Progress and Some Problems

Environmental impact assessment is discussed for the case of a single biological species, when observations can be taken at both the affected (Impact) area and a nearby control. A procedure for testing the null hypothesis is described and problems of model uncertainty are discussed. It is argued that no single number, such as the p-value for this test, can adequately summarize the data. Several summaries are needed in order to adequately describe the size of the effect and the strength of the evidence and to allow for model uncertainty. Some suggestions are offered.