cssi/SciSciGPT-SciSciNet huggingface dataset:
783: Morbidities associated with a disproportionately high risk of amniotic fluid embolism: a contemporary population-based study

mined. Multivariable analysis was performed to identify demographic factors or medical conditions present on admission that were independently associated with severe MM. RESULTS: Among 115,502 women who delivered during the study period, 332 (0.29%, 95% CI 0.26% 0.32%) experienced severe MM. The frequency of severe MM varied significantly across hospitals, ranging from 0.00% to 1.02% (p 0.001). Postpartum hemorrhage was responsible for half of severe MM, with hypertension (26%), nonhypertensive cardiopulmonary complications (16%), infection (5%), and other maternal medical conditions (3%) accounting for the remainder. In multivariable analysis, various patient factors were associated with the occurrence of severe MM (Table). Ninety-five percent of women who had severe MM had at least one of the risk factors identified to be significant in the multivariable regression. CONCLUSION: Severe MM can be quantified, and its contributing etiologies and associated factors identified. Measurement of severe MM may be a useful tool in quality improvement initiatives aimed at combating adverse maternal outcomes.
Apolipoprotein A-I Modulates Regulatory T Cells in Autoimmune LDLr−/−, ApoA-I−/− Mice

The immune system is complex, with multiple layers of regulation that serve to prevent the production of self-antigens. One layer of regulation involves regulatory T cells (Tregs) that play an essential role in maintaining peripheral self-tolerance. Patients with autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis have decreased levels of HDL, suggesting that apoA-I concentrations may be important in preventing autoimmunity and the loss of self-tolerance. In published studies, hypercholesterolemic mice lacking HDL apoA-I or LDLr−/−, apoA-I−/− (DKO), exhibit characteristics of autoimmunity in response to an atherogenic diet. This phenotype is characterized by enlarged cholesterol-enriched lymph nodes (LNs), as well as increased T cell activation, proliferation, and the production of autoantibodies in plasma. In this study, we investigated whether treatment of mice with lipid-free apoA-I could attenuate the autoimmune phenotype. To do this, DKO mice were first fed an atherogenic diet containing 0.1% cholesterol, 10% fat for 6 weeks, after which treatment with apoA-I was begun. Subcutaneous injections of 500 μg of lipid-free apoA-I was administered every 48 h during the treatment phase. These and control mice were maintained for an additional 6 weeks on the diet. At the end of the 12-week study, DKO mice showed decreased numbers of LN immune cells, whereas Tregs were proportionately increased. Accompanying this increase in Tregs was a decrease in the percentage of effector/effector memory T cells. Furthermore, lipid accumulation in LN and skin was reduced. These results suggest that treatment with apoA-I reduces inflammation in DKO mice by augmenting the effectiveness of the LN Treg response.
Group Training in Communication Skills for Couples: A Preliminary Report.

Abstract This article reports on the initial development and evaluation of a group skill-training program for couples. The program, entitled the Communication Skills Workshop (CSW), aims at improving communication and problem-solving skills within the context of relationships. The orientation of the CSW is preventive and educational in that it (a) serves couples prior to the onset of serious relationship discord, and (b) focuses on the learning of general communication skills and problem-solving strategies rather than the amelioration of specific relationship conflicts.
The role and impact of monetary policy in CEFTA countries

An effective monetary policy requires a stable relationship between the money stock and macroeconomic variables such as output, price level, interest rates, and exchange rates. A dynamism of structural changes in transition economies of eastern Europe makes such stability far from obvious. This is reflected in the fact that a stable demand for money function cannot be estimated even for the most advanced East European countries: Poland, Hungary, and the Czech Republic. Empirical analysis of the relationship between nominal variables indicates rather limited relationships as well. Therefore, all that can be expected from monetary policy in eastern Europe is not to be too tight so as to starve the economy of needed liquidity and not to be too loose so as to ignite inflation.
A new method of coating oilfield core for laboratory studies

A new method has been developed for coating oilfield core for laboratory studies. It consists of applying a steel coating and aluminum wraps around the outer surface of a core. The strength of the coating, the short time needed to apply it, and its low cost are the major advantages of this new method.
Amplified and tissue-directed expression of retroviral vectors using ping-pong techniques.

Ping-pong amplification is an efficient process by which helper-free retrovirions replicate in cocultures of cell lines that package retroviruses into distinct hostrange envelopes [11]. Transfection of a retroviral vector DNA into these cocultures results in massive virus production, with potentially endless cross-infection between different types of packaging cells. Because the helperfree virus spreads efficiently throughout the coculture, it is unnecessary to use dominant selectable marker genes, and the retroviral vectors can be simplified and optimized for expressing a single gene of interest. The most efficient ping-pong vector, pSFF, derived from the Friend erythroleukemia virus, has been used for high-level expression of several genes that could not be expressed with commonly employed two-gene retroviral vectors. Contrary to previous claims, problems of vector recombination are not inherent to ping-pong methods. Indeed, the pSFF vector has not formed replication-competent recombinants as shown by stringent assays. Here we review these methods, characterize the ping-pong process using the human erythropoietin gene as a model, and describe a new vector (pSFY) designed for enhanced expression in T lymphocytes. Factors that limit tissue-specific expression are reviewed.
SU‐E‐I‐26: Estimation of Micro‐Angiographic Fluoroscope (MAF) Gain Settings for Digital Subtraction Angiography (DSA) Based on the Fluoroscopic Exposure

Purpose: The MAF is a new high‐resolution detector which is being clinically evaluated in neuro‐vascular procedures. The detector contains a large‐dynamic‐range, high‐sensitivity light image intensifier with variable gain. Since the MAF is a research prototype only partially integrated with the clinical system, x‐ray technique parameters must be set manually. To improve workflow we developed an automatic method to estimate and set the proper LII voltage (MAF gain) for DSA acquisition based on the fluoroscopic parameters. Methods: The detector entrance exposure (XD) can be written as the x‐ray tube output exposure (Xo) times an object attenuation factor and an inverse‐square correction. If the object attenuation, scatter and distances are unchanged and the effect of x‐ray kVp changes are neglected, then the DSA XD can be expressed as the ratio of Xo(DSA)/Xo(Fluoroscopy) multiplied with XD(fluoroscopy). We measured Xo for fluoroscopy and DSA for mAs and kVp ranges appropriate to neuro‐ vascular interventions and fit the data with a 2D function. To estimate the XD(Fluoroscopy) we derived a curve of XD versus LII‐voltage for a mid‐ dynamic‐range average pixel gray‐level. Since the MAF system during clinical fluoroscopy automatically adjusts the LII voltage until the desired gray‐level value is achieved, by reading that voltage we can estimate the XD(Fluoroscopy). Using the 2D‐fit function, Xo(DSA) is automatically calculated for the kVp and mA values set and XD(DSA) can be estimated using the relation above. Using the inverse LII calibration curve, the proper LII‐voltage can be determined for the desired average gray‐level. Results: The algorithm was implemented and evaluated in thirty‐two in‐vivo DSA runs on rabbits. The proper LII voltage was selected in all cases with no failures. Conclusions: Using the fluoroscopic LII gain setting to determine the appropriate DSA setting can greatly improve the workflow in clinical evaluations of the MAF. NIH Grants R01‐EB008425, R01‐EB002873 and an equipment grant from Toshiba Medical Systems Corp
Longstreth et al.’s reaction time model: Some comments

Longstreth and his colleagues (Longstreth, 1988; Longstreth & Alcorn, 1987; Longstreth, El-Zahhar, & Alcorn, 1985) have recently introduced a choice reaction time model based on a simple and novel behavioral explanation. However, as pointed out in this paper, there are several issues and problems associated with their model. In addition, it is shown that the reaction-time equation by Longstreth and his colleagues represents a special case of the general power law proposed earlier by this author. The type of behavioral explanation used by Longstreth and his colleagues is extended to the case of unequal stimulus probabilities. An alternative model is also developed using the repetition effect as a starting point.
Negotiating Plausibility: Intervening in the Future of Nanotechnology

The national-level scenarios project NanoFutures focuses on the social, political, economic, and ethical implications of nanotechnology, and is initiated by the Center for Nanotechnology in Society at Arizona State University (CNS-ASU). The project involves novel methods for the development of plausible visions of nanotechnology-enabled futures, elucidates public preferences for various alternatives, and, using such preferences, helps refine future visions for research and outreach. In doing so, the NanoFutures project aims to address a central question: how to deliberate the social implications of an emergent technology whose outcomes are not known. The solution pursued by the NanoFutures project is twofold. First, NanoFutures limits speculation about the technology to plausible visions. This ambition introduces a host of concerns about the limits of prediction, the nature of plausibility, and how to establish plausibility. Second, it subjects these visions to democratic assessment by a range of stakeholders, thus raising methodological questions as to who are relevant stakeholders and how to activate different communities so as to engage the far future. This article makes the dilemmas posed by decisions about such methodological issues transparent and therefore articulates the role of plausibility in anticipatory governance.
Facility Effects on Performance Measurements of Micropropulsion Systems that Utilize Gas Expansion

Facilities can affect the measurement of spacecraft propulsion system performance in a variety of ways. In this study an underexpanded freejet is used to simulate experimentally a micropropulsion system such as those thatoperate on the expansion of propellant gases through nozzle geometries. Facility effects on the thrust measured by a torsion thrust stand installed in two facilities with distinctly different characteristics have been quantified over a steady-state thrust range from 10 to 480 μN. The two facilities varied in dimension and pumping capacity with background pressures ranging from 10 - 6 to 10 - 4 torr. In both facilities the measured thrust decreased with increasing facility background pressure. At a thrust level of 10 μN, the thrust decreased by approximately 20% at a facility background pressure of 2 x 10 - 4 torr relative to the thrust measured at 2 x 10 - 6 torr; however, a similar background pressure only resulted in a 4% reduction in thrust at 120 μN. The larger percent decrease in measured thrust for a given background pressure in the low thrust range has implications for the design of micropropulsion test facilities. The facility background pressure effect contributes to less than 2% error for the thrust range from 10 to 480 μN at background pressures less than 10 - 5 torr, suggesting that low background pressures are necessary for accurate thrust measurements below 500 μN. An empirical formulation based on background-plume penetration theory provides estimates of the thrust degradation as a function of facility background pressure. The empirical model fits the experimental data reasonably well for jet centerline values of the background gas radius of penetration into the freejet plume.
Electric-Field-Induced Raman Scattering by LO Phonons in an External Magnetic Field

A calculation of the electro-optic (Fr\"ohlich-interaction) contribution to the electric-field-induced Raman-scattering tensor of LO phonons in a crossed magnetic field is presented for "two-band" scattering processes involving continuum electron and hole intermediate states. The continuum states in crossed electric and magnetic fields can be described by harmonic-oscillator wave functions. The intraband-Fr\"ohlich-interaction matrix element is found to be directly proportional to the average separation of electron and hole in the intermediate state, a result similar to that for electric-field-induced scattering via discrete exciton states in no magnetic field.
A Hybrid LES/RANS Calculation of Subsonic, Supersonic Hot Jet Noise

In this paper, pure RANS and hybrid LES/RANS procedures have been investigated for the simulation of jet noise from subsonic and supersonic, hot jets. The aerodynamic predictions from the RANS calculations agree well with experimental measurements. It is emphasized that the RANS-based acoustic analogy method used is incapable of capturing the sound characteristics at small jet angles, which are dominated by the sound radiated from large-scale turbulent structures. The hybrid LES/RANS approach investigated by Shur et al is examined. The preliminary results for a subsonic, hot jet (Set Point 46 in Tanna’s experiment) have shown that this method can capture, satisfactorily, the near-filed velocity and pressure signatures induced by large-scale turbulent structures. It is our goal to establish the feasibility and advantages of using a high-fidelity tool for predicting both small scale and large-scale supersonic jet noise with arbitrary complex geometries and under realistic flight conditions.Copyright © 2007 by ASME
Time series based analysis for primary chatter in metal cutting

Primary chatter is investigated experimentally using both traditional and frequency domain techniques. The experiment was conducted on a CNC lathe using coated carbide cutting inserts. The tool vibrations and cutting forces were measured and analyzed for different sets of cutting conditions. The experimental results indicated that the tool vibrations are more sensitive to the cutting geometry than the cutting forces. Also, the feed rate was found to be the most critical parameter which leads the system into chaotic behavior. In particular, the wavelet transform technique was used to analyze chatter signals. It clearly identified the transient boundary and the occurrence of the built-up edge (BUE). Based on the frequency information contained in the wavelet transforms, the cutting process is probably quadratically non-linear. In addition, for high feed rate, chaotic behavior was observed. Traditional techniques were also used to study the chaotic behavior of the process. These techniques include phase plane, power spectra, Poincare map and fractal dimensions. They all agreed with the observation obtained by the wavelet transform regarding chaotic motion.
Status of the Monte Carlo library least-squares (MCLLS) approach for non-linear radiation analyzer problems

Abstract The Center for Engineering Applications of Radioisotopes (CEAR) has been working for over a decade on the Monte Carlo library least-squares (MCLLS) approach for treating non-linear radiation analyzer problems including: (1) prompt gamma-ray neutron activation analysis (PGNAA) for bulk analysis, (2) energy-dispersive X-ray fluorescence (EDXRF) analyzers, and (3) carbon/oxygen tool analysis in oil well logging. This approach essentially consists of using Monte Carlo simulation to generate the libraries of all the elements to be analyzed plus any other required background libraries. These libraries are then used in the linear library least-squares (LLS) approach with unknown sample spectra to analyze for all elements in the sample. Iterations of this are used until the LLS values agree with the composition used to generate the libraries. The current status of the methods (and topics) necessary to implement the MCLLS approach is reported. This includes: (1) the Monte Carlo codes such as CEARXRF, CEARCPG, and CEARCO for forward generation of the necessary elemental library spectra for the LLS calculation for X-ray fluorescence, neutron capture prompt gamma-ray analyzers, and carbon/oxygen tools; (2) the correction of spectral pulse pile-up (PPU) distortion by Monte Carlo simulation with the code CEARIPPU; (3) generation of detector response functions (DRF) for detectors with linear and non-linear responses for Monte Carlo simulation of pulse-height spectra; and (4) the use of the differential operator (DO) technique to make the necessary iterations for non-linear responses practical. In addition to commonly analyzed single spectra, coincidence spectra or even two-dimensional (2-D) coincidence spectra can also be used in the MCLLS approach and may provide more accurate results.
Estimation of Evolutionary Parameters with Phylogenetic Trees

An important issue in the phylogenetic analysis of nucleotide sequence data using the maximum likelihood (ML) method is the underlying evolutionary model employed. We consider the problem of simultaneously estimating the tree topology and the parameters in the underlying substitution model and of obtaining estimates of the standard errors of these parameter estimates. Given a fixed tree topology and corresponding set of branch lengths, the ML estimates of standard evolutionary model parameters are asymptotically efficient, in the sense that their joint distribution is asymptotically normal with the variance-covariance matrix given by the inverse of the Fisher information matrix. We propose a new estimate of this conditional variance based on estimation of the expected information using a Monte Carlo sampling (MCS) method. Simulations are used to compare this conditional variance estimate to the standard technique of using the observed information under a variety of experimental conditions. In the case in which one wishes to estimate simultaneously the tree and parameters, we provide a bootstrapping approach that can be used in conjunction with the MCS method to estimate the unconditional standard error. The methods developed are applied to a real data set consisting of 30 papillomavirus sequences. This overall method is easily incorporated into standard bootstrapping procedures to allow for proper variance estimation.
Learning web development: challenges at an earlier stage of computing education

Web development can provide a rich context for exploring computer science concepts and practicing computational creativity. However, little is known about the experiences that people have when first learning web development. In this paper, we investigate the help-seeking activity of forty-nine students in an introductory web development course. By applying content analysis to the help forums of the course, we characterize the challenges they encountered and sought help for, relating them to development, instruction, technology, content, and design issues. We apply a second level of content analysis to the development issues, identifying aspects of learning HTML, CSS, and JavaScript that challenged students most often. Finally, we identify several computational concepts that relate to these challenges, including notation, hierarchies and paths, nesting, parameters and arguments, and decomposition and abstraction. We conclude with a discussion on the implications of our findings for computing education.
Mesons and the structure of nucleons. Part IV. The nucleon-nucleon potential

Abstract The atomic model, in which physical nucleons are described as compound systems of a nucleon core plus a single pion, has been used as the basis for a computation of the low-energy interaction between two physical nucleons. Advantage is taken of previous work for the specification of the interaction between the pion and the nucleon core in the different possible states of total angular momentum and isotopic spin. An initial simplification, where we replace one of the “atoms” by an “effective scattering center” is only moderately successful in reproducing the gross features of the observed nucleon-nucleon interaction. The full computation (approached in the spirit of the Heitler-London approximation to the H-H interaction) improves on the qualitative fit, but it turns out to be impossible to reproduce simultaneously the asymptotic behavior of both the central and tensor terms in the nucleon-nucleon potential using a reasonable set of pion-core interactions. A significant result is the derivation, using the simplified model, of a nucleon-nucleon spin-orbit interaction whose range is shorter than that of the other terms in the potential. Our computation thus provides a strong indication that the spin-orbit interaction may arise from the same features of the pion-nucleon interaction as give rise to the resonant pion-nucleon scattering in the state of T = J = 3 2 .
Spectrum Access Games and Strategic Learning in Cognitive Radio Networks for Delay-Critical Applications

With the current proliferation of high bandwidth and delay-sensitive multimedia applications and services, each wireless user will try to maximize its utility by acquiring as much spectrum resources as possible unless a preemptive mechanism exists in the network. Thus, emerging solutions for dynamic spectrum access in cognitive radio networks will need to adopt market-based approaches in order to effectively regulate the available resources. In this paper, we show how various centralized and decentralized spectrum access markets can be designed based on a stochastic game framework, where wireless users (also referred to as secondary users) can compete over time for the dynamically available transmission opportunities (spectrum ldquoholesrdquo). When operating in such spectrum access ldquomarkets,rdquo wireless users become selfish, autonomous agents that strategically interact in order to acquire the necessary spectrum opportunities. We also show how wireless users can successfully compete with each other for the limited and time-varying spectrum opportunities, given the experienced dynamics in the wireless network, by optimizing both their external actions (e.g., the resource bids, power and channel used for transmission, etc.) and their internal actions (e.g., the modulation schemes, etc.). To determine their optimal actions in an informationally decentralized setting, users will need to learn and model directly or indirectly the other users' responses to their external actions. We studied the outcome of various dynamic interactions among self-interested wireless users possessing different knowledge and determine that the proposed framework can lead to multiuser communication systems that achieve new measures of efficiency, rationality and fairness. Lastly, our illustrative results show that the presented game-theoretic solution for wireless resource management enables users deploying enhanced (ldquosmarterrdquo) learning and communication algorithms and being able to make efficient use of the spectrum resources can derive higher utilities. This presents the designers of wireless devices and systems with important incentives to endow their next-generation products and services with enhanced capabilities to gather information, learn, and strategically compete for resources in the emerging spectrum resource markets made possible by the cognitive radio network technologies.
Ion-molecule reaction of CH3+, C2H5+, C3H5+ and C3H7+ with unsaturated C2, C3 and C4 hydrocarbons

Abstract The reaction rate constants and product distributions for reaction of CH3+ and C2H5+ with ethylene, C2H5+ with propene and cyclopropane, and C3H5+ and C3H7+ with the four butene isomers are reported here. The results were obtained using a Dempster-ion cyclotron resonance tandem mass spectrometer which mass analyzes and decelerates the reactant ions to less than 0.1 eV. The internal excitation energy of all but the methyl reactant ions may be varied through unreactive collisions in the first stage of the instrument. Deuterated reactant ions have been used in an attempt to classify reaction channels according to models such as hydride abstraction, proton transfer or complex formation. Most of the major reaction channels studied here are best described as proceeding through a short-lived intermediate complex. The reactions of C2H5+ with propene and cyclopropane are particularly interesting since the major product, C4H9+, is produced through both direct proton transfer and complex formation.
Use of an observation ward in a community hospital

A six-bed observation ward has been an integral part of our community hospital emergency department for 10 years. During a recent 4-month period, 574 patients were admitted with 65 different clinical presentations. Length of stay, treatment, complications, and disposition were evaluated. An estimated 1.7 hospital admissions per day were avoided at an annual cost savings of $240,000. Guidelines have been developed which avoid most potential pitfalls in the use of an observation ward. Significant flexibility is gained and improved patient care is possible with the addition of an observation ward to the emergency department.
Glioblastoma Stem Cells: A Neuropathologist's View

Glioblastoma (WHO Grade IV) is both the most common primary brain tumor and the most malignant. Advances in the understanding of the biology of the tumor are needed in order to obtain a clearer picture of the mechanisms driving these tumors. To neuropathologists, glioblastoma is a tumor that represents a complex system of migrating pleomorphic tumor cells, proliferating blood vessels, infiltrating inflammatory cells, and necrosis. This review will highlight how the glioma stem cell concept brings these elements together into a collective whole, interacting with microenvironmental influences in complex ways. Borrowing from chaos theory a vocabulary of “self organizing systems” and “complex adaptive systems” that seem useful in describing these pathologic features, a new paradigm of glioblastoma biology will be proposed that genetic changes should be understood in a three dimensional framework as they relate not only to the tumor cells themselves but also to the multicellular hierarchical unit, not isolated from, but responsive to, its local milieu. In this way we will come to better appreciate the impact our therapeutic interventions have on the regional phenotypic heterogeneity that exists within the tumor and the intercellular communications directing adaptation and progression.
Reaction Modulation Spectoscopy: A New Approach to Quantifying Reaction Mechanisms†

We report a new experimental method, reaction modulation spectroscopy, (RMS), that shows great promise in enabling the systematic analysis of complicated oxidation mechanisms over the full range of atmospheric pressures and temperatures. The method is a form of difference spectroscopy in which we employ FTIR absorption spectroscopy in a high-pressure flow system (HPFS) where a plume of reacting species is examined before any significant fraction reaches the tube wall. The onset of the reaction is modulated by modulating the flow of an initiating radical species over a period that is short compared to any associated with experimental drifts. Spectra obtained with the radical source on and off are ratioed, giving a transmittance spectrum showing only the effects of the reaction modulation. The system is in a steady state, so signal averaging over long periods (up to several days) may be employed, if necessary, to obtain a high signal-to-noise ratio. Because no bulk reagents are disturbed in the process, we ...
Incremental burden of congestive heart failure among elderly with Alzheimer's

Objective: A complex relationship exists between Alzheimer's disease (AD) and other co-existing co-morbidities such as congestive heart failure (CHF) with implications for health resource utilization (HRU) and cost of care. Study objective was to assess HRU and cost of care in elderly with AD and with or without concomitant CHF. Methods: All elderly (≥65 years) from an academic healthcare system diagnosed with AD in 1999 (n = 904) and matched AD-free controls (n = 3616). Each group was subdivided into those with and without a CHF diagnosis. Costs and HRU were obtained from Medicare databases for 1999 and 2000. Costs and HRU were compared using ANOVA and Wilcoxon rank sum tests. Regressions were used to model the effect of AD and CHF on outcomes. Results: Mean annual cost were $20,888 for AD + CHF group, $5473 for only AD group, $17,700 for only CHF group and $4578 for the control group (no-AD and no-CHF). After adjusting for covariates, AD + CHF group had an eight-fold increase in total cost, while only C...
Endonuclease Associations with Three Distinct Editosomes in Trypanosoma brucei

Three distinct editosomes, typified by mutually exclusive KREN1, KREN2, or KREN3 endonucleases, are essential for mitochondrial RNA editing in Trypanosoma brucei. The three editosomes differ in substrate endoribonucleolytic cleavage specificity, which may reflect the vast number of editing sites that need insertion or deletion of uridine nucleotides (Us). Each editosome requires the single RNase III domain in each endonuclease for catalysis. Studies reported here show that the editing endonucleases do not form homodimeric domains, and may therefore function as intermolecular heterodimers, perhaps with KREPB4 and/or KREPB5. Editosomes isolated via TAP tag fused to KREPB6, KREPB7, or KREPB8 have a common set of 12 proteins. In addition, KREN3 is only found in KREPB6 editosomes, KREN2 is only found in KREPB7 editosomes, and KREN1 is only found in KREPB8 editosomes. These are the same associations previously found in editosomes isolated via the TAP-tagged endonucleases KREN1, KREN2, or KREN3. Furthermore, TAP-tagged KREPB6, KREPB7, and KREPB8 complexes isolated from cells in which expression of their respective endonuclease were knocked down were disrupted and lacked the heterotrimeric insertion subcomplex (KRET2, KREPA1, and KREL2). These results and published data suggest that KREPB6, KREPB7, and KREPB8 associate with the deletion subcomplex, whereas the KREN1, KREN2, and KREN3 endonucleases associate with the insertion subcomplex.
Continuous maximal reverse nearest neighbor query on spatial networks

Given a set S of sites and a set O of weighted objects located on a road network, the optimal network location (ONL) query computes a location on the road network where introducing a new site would maximize the total weight of the objects that are closer to the new site than to any other site. The existing solutions for optimal network location query assume that sites and objects rarely change their location over time, whereas there are numerous new applications with which sites and/or objects frequently change location. Unfortunately, the existing solutions for optimal network location query are not applicable to answer such these so-called dynamic optimal network location queries (DONL), since the result generated by such solutions is most probably invalid by the time computation is complete. In this paper for the first time we formalize the problem of DONL queries as Continuous Maximal Reverse Nearest Neighbor (CMaxRNN) queries on spatial networks, and introduce an approach that allows for efficient and incremental update of MaxRNN query results on spatial networks. With an extensive experimental study we verify and evaluate the efficiency of our proposed approach with both synthetic and real-world datasets.
Communicating through pictures and words: Understanding the role of affect and cognition in processing visual and verbal information

The interaction of affect and cognition was explored as four types of processor groups (high affect/low cognition, low affect/high cognition, high affect/high cognition, and low affect/low cognition) and investigated in terms of responses to a visual stimulus, a verbal stimulus, and a combination visual/verbal stimulus. This exploratory investigation suggests that high-affect individuals (affective processors) respond more favorably to a visual ad than the other groups, and individuals high in both affect and cognition (combined processors) respond more favorably to a combination visual/verbal ad. Theoretical and managerial implications as well as directions for future research are discussed. © 2006 Wiley Periodicals, Inc.
Modeling alloy and energy utilization in high volume die casting

Die casting is a widely used high-technology manufacturing process which is both capital and energy intensive. While there are several economic and environmental advantages to die casting, the high energy consumption required to cast products warrants attention. Operational and design decisions within a die casting process can have a significant impact on the total energy use and equivalent carbon dioxide emissions. An absorbing-state Markov chain model of the die casting process represents the possible flows of material and measures the resource consumption of the most energy-intensive steps. The model supports decision-makers considering possible design, investment, and operational decisions, such as the purchase of new equipment. Data elements necessary to implement the model are specified, as are the necessary reference data for analyzing the emissions related to energy consumption. The use of the model is illustrated with a historical case study from a specific product design decision. Prescriptive uses of the model based on this case study are also analyzed, although the model supports a variety of analyses.
Mitochondrial-Nuclear Epistasis Contributes to Phenotypic Variation and Coadaptation in Natural Isolates of Saccharomyces cerevisiae

Mitochondria are essential multifunctional organelles whose metabolic functions, biogenesis, and maintenance are controlled through genetic interactions between mitochondrial and nuclear genomes. In natural populations, mitochondrial efficiencies may be impacted by epistatic interactions between naturally segregating genome variants. The extent that mitochondrial-nuclear epistasis contributes to the phenotypic variation present in nature is unknown. We have systematically replaced mitochondrial DNAs in a collection of divergent Saccharomyces cerevisiae yeast isolates and quantified the effects on growth rates in a variety of environments. We found that mitochondrial-nuclear interactions significantly affected growth rates and explained a substantial proportion of the phenotypic variances under some environmental conditions. Naturally occurring mitochondrial-nuclear genome combinations were more likely to provide growth advantages, but genetic distance could not predict the effects of epistasis. Interruption of naturally occurring mitochondrial-nuclear genome combinations increased endogenous reactive oxygen species in several strains to levels that were not always proportional to growth rate differences. Our results demonstrate that interactions between mitochondrial and nuclear genomes generate phenotypic diversity in natural populations of yeasts and that coadaptation of intergenomic interactions likely occurs quickly within the specific niches that yeast occupy. This study reveals the importance of considering allelic interactions between mitochondrial and nuclear genomes when investigating evolutionary relationships and mapping the genetic basis underlying complex traits.
Experimental boundaries for the origin and evolution of carbonatites

An integrated model is presented for the generation of crustal carbonatites in rift environments from mantle carbon, both primordial and recycled through subduction. The carbon is involved in the generation of melts in the asthenosphere and the melts are then processed in the lithosphere associated with continental rifting. Parental nephelinitic melts from about 75 km depth then yield the carbon in the form of carbonatite at shallower depths in the upper mantle, or within the crust. Selected experimental phase equilibrium data are reviewed to test parts of the model. Similar tests can be made for carbonatites formed in different tectonic environments. Experiments with lherzolite (synthetic and natural) confirm that with CO_2 and H_2O at depths greater than about 75 km, near-solidus liquids correspond to Ca-Mg carbonatites, enriched in alkalis; the prospect that primary carbonatites could be erupted from the mantle justifies a search for them, but volume relationships favor an origin by differentiation for most occurrences. A wide miscibility gap between silicate and carbonate liquids with variable Ca/Na and Ca/Mg extends from crust to mantle pressures, but primitive CO_2-bearing nephelinites do not yield immiscible carbonatite magmas at 75 km depth; immiscibility should occur commonly at shallower depths, certainly in the crust. Fractional crystallization of nepheline-normative magmas in the crust can yield the series of rocks occurring in some alkalic complexes with carbonatites. Carbonatite magmas differentiate: crystallization paths confirm the prospect of fractional crystallization of dolomite and calcite and the coprecipitation of calcite and bastnaesite from magmas.
New funding for ocean research proposed for 2008

The Bush Administration will request an additional US$143 million for coastal and marine research and conservation for Fiscal Year (FY) 2008, officials announced on 26 January. “It is clear that good stewardship of the oceans, coasts, and Great Lakes must be a national priority,” said John H. Marburger III, director of the U.S. Office of Science and Technology Policy.
DOES MEMBERSHIP HAVE ITS REWARDS? THE EFFECTS OF RACE AND HALL OF FAME MEMBERSHIP ON FOOTBALL CARD VALUES

This article examines the effects of the race and Hall of Fame membership of professional football players on the value of their “rookie” football cards. Several studies have examined the impact of race on the value of baseball cards, but only one paper has examined this topic among football card collectors. Data were derived from 177 black and white football players who are members of the NFL Hall of Fame or who have been on the final voting ballot for the Hall. All of the players in the sample started their careers after professional football became racially integrated. Data for each player's race, value of their rookie card, card availability (scarcity), performance, Hall membership, and position were obtained from secondary sources. The principle finding of the study is that when controlling for factors such as position, performance, and card scarcity, race applies an independent effect on the value of the rookie cards of NFL Hall of Fame members, but not among non-Hall of Fame cards. Speculation on w...
Characterization by electron microscopy of the complex formed between T4 bacteriophage gene 32-protein and DNA

Abstract Techniques have been developed for visualization of gene 32-protein/DNA complexes by electron microscopy. With DNA in excess, gene 32-protein can be seen to bind co-operatively to single-stranded DNA. With protein in excess, all single-strands appear to be uniformly coated with protein. The saturated complex has a flexible rod-like conformation, with a diameter of about 60 A and a length of about 4.6 A per nucleotide. This structure is unchanged in the presence of 1 m m -spermine, a condition which induces extensive folding in the free single-strands. Using glutaraldehyde fixation, gene 32-protein induced denaturation of double-stranded DNA's can be visualized at physiological temperatures. The denaturation map derived with bacteriophage lambda DNA closely resembles that obtained earlier with heat and alkaline denaturation in the absence of protein (Inman, 1967) , indicating that the protein preferentially invades A + T rich double-helical regions, without a requirement for a physical discontinuity such as a cleaved phosphodiester bond or a double-stranded end. With supercoiled DNA, only a single short region of double-helix is opened by gene 32-protein, reflecting the difficulty of denaturation where unwinding is geometrically restricted.
Physical properties of extended‐chain high‐density polyethylene

Extended-chain high-density polyethylene prepared through crystallization at high pressure is substantially stiffer and somewhat stronger than normal folded-chain HDPE. With weight-average molecular weight in the range normal for molding or extrusion resins, the extended-chain material is inductile and brittle; but with molecular weight near 2,000,000, the resin can be rigid and tough. This rigid, tough material can be converted to articles through some of the solid-state processes developed for metals. The volume–temperature behavior of HDPE at 5000 atmospheres appears to reflect a polymorphic transition between orthorhombic and triclinic phases.
Atmospheric channel characterization for ORCA testing at NTTR

Abstract The DARPA Optical RF Communications Adjunct (ORCA) program was created to bring high data rate networking to the warfighter via airborne platforms. Recent testing of the ORCA system was conducted by the Northrop Grumman Corporation (NGC) at the Nevada Test and Training Range (NTTR) at the Nellis Air Force Range near Tonopah, NV. The University of Central Florida (UCF) conducted a parallel test to measure path-averaged values of the refractive-index structure parameter, the inner scale of turbulence, and the outer scale of turbulence along the ORCA propagation path from an airborne platform to the ground at Antelope Peak. In addition, weather instrumentation was set up at ground level on Antelope Peak to measure local conditions on the mountain top. This paper presents background information on expected atmospheric conditions for the channel, models that were used by UCF for the measurements, path-averaged values of the three atmospheric parameters, and a C n2 profile model as a function of altitude.
Take a Professional to Lunch: A Process to Establish a Professional Network.

A review of the marketing literature suggests that students develop personal marketing or sales plans to find their first job and subsequent career. Publishers are providing students access to online resources linked to career information. However, the person who knows most about a given career is the person who is working at that job on a daily basis (i.e., the fully employed professional). This paper builds on previous studies by providing a selling process students have used successfully to develop professional networks.
Mapping cortical representations of the rodent forepaw and hindpaw with BOLD fMRI reveals two spatial boundaries.

Electrical stimulation of the rat forepaw and hindpaw was employed to study the spatial distribution of BOLD fMRI. Averaging of multiple fMRI sessions significantly improved the spatial stability of the BOLD signal and enabled quantitative determination of the boundaries of the BOLD fMRI maps. The averaged BOLD fMRI signal was distributed unevenly over the extent of the map and the data at the boundaries could be modeled with major and minor spatial components. Comparison of three-dimensional echo-planar imaging (EPI) fMRI at isotropic 300 μm resolution demonstrated that the border locations of the major spatial component of BOLD signal did not overlap between the forepaw and hindpaw maps. Interestingly, the border positions of the minor BOLD fMRI spatial components extended significantly into neighboring representations. Similar results were found for cerebral blood volume (CBV) weighted fMRI obtained using iron oxide particles, suggesting that the minor spatial components may not be due to vascular mislocalization typically associated with BOLD fMRI. Comparison of the BOLD fMRI maps of the forepaw and hindpaw to histological determination of these representations using cytochrome oxidase (CO) staining demonstrated that the major spatial component of the BOLD fMRI activation maps accurately localizes the borders. Finally, 2–3 weeks following peripheral nerve denervation, cortical reorganization/plasticity at the boundaries of somatosensory limb representations in adult rat brain was studied. Denervation of the hindpaw caused a growth in the major component of forepaw representation into the adjacent border of hindpaw representation, such that fitting to two components no longer led to a better fit as compared to using one major component. The border of the representation after plasticity was the same as the border of its minor component in the absence of any plasticity. It is possible that the minor components represent either vascular effects that extend from the real neuronal representations or the neuronal communication between neighboring regions. Either way the results will be useful for studying mechanisms of plasticity that cause alterations in the boundaries of neuronal representations.
The Rac1 inhibitor, NSC23766, depolarizes adhesive secretion, endomembrane cycling, and tip growth in the fucoid alga, Silvetia compressa

Proper cell morphogenesis is dependent on the establishment and expression of cellular polarity. In the fucoid zygote, cell shape is critical for establishing the developmental pattern of the adult, and is achieved by guiding insertion of new membrane and wall to the rhizoid tip. Selection and growth of the appropriate tip site are accompanied by formation of dynamic actin arrays associated with the actin-nucleating Arp2/3 complex. In eukaryotes, a major pathway for activation of the Arp2/3 complex is via the Rho family GTPase, Rac1, which stimulates the Scar/WAVE complex. To determine whether Rac1 controls actin nucleation in Silvetia compressa (J. Agardh) E. Serrao, T. O. Cho, S. M. Boo et Brawley, we tested the effects of the Rac1-specific inhibitory compound, NSC23766, on actin dependent processes and on actin arrays. We found that NSC23766 disrupted polar secretion of adhesive, polarization of endomembranes, and tip-focused growth in the rhizoid. Similarly, NSC23766 altered actin and Arp2 localization in the growing rhizoid. In contrast, NSC23766 had no effect on selection of the growth site or on cytokinesis. These data suggest that Rac1 participates in nucleation of specific actin arrays in the developing zygote.
New cloning vectors using benomyl resistance as a dominant marker for selection inNeurospora crassa and in other filamentous fungi

Abstract We describe five new plasmid vectors derived from pBR322 that carry theNeurospora crassa β-tubulin gene conferring resistance to benomyl. The benomyl resistance gene has been modified to eliminate an internalEcoRI site to facilitate the cloning ofEcoRI restriction fragments. These plasmids allow rapid subcloning of fragments from one replicon to another without insert fragment purification due to the presence of different drug resistance markers (resistance to kanamycin, tetracycline, or chloramphenicol) carried on the plasmids. These vectors will allow rapid transformation ofN. crassa and other filamentous fungi to allow phenotypic characterization of subcloned fragments.