cssi/SciSciGPT-SciSciNet huggingface dataset:
SINBAD: A neocortical mechanism for discovering environmental variables and regularities hidden in sensory input

We propose that a top priority of the cerebral cortex must be the discovery and explicit representation of the environmental variables that contribute as major factors to environmental regularities. Any neural representation in which such variables are represented only implicitly (thus requiring extra computing to use them) will make the regularities more complex and therefore more difficult, if not impossible, to learn. The task of discovering such important environmental variables is not an easy one since their existence is only indirectly suggested by the sensory input patterns the cortex receives – these variables are “hidden”. We present a candidate computational strategy for (i) discovering regularity-simplifying environmental variables, (ii) learning the regularities, and (iii) using regularities in perceptual and decision-making tasks. The SINBAD computational model discovers useful environmental variables through a search for different, but nevertheless highly correlated, functions of any kind over nonoverlapping subsets of the known variables, this being indicative of some important environmental variable that is responsible for the correlation. We suggest that such a search is performed in the neocortex by the dendritic trees of individual pyramidal cells. According to the SINBAD model, the basic function of each pyramidal cell is to (i) discover and represent one of the regularity-simplifying environmental variables and (ii) learn to infer the state of its variable from the states of other variables, represented by other pyramidal cells. A network of such cells – each cell just attending to representation of its variable – can function as a sophisticated and useful inferential model of the outside world.
Question Master: An Evaluation of a Web-Based Decision-Support System for Use in Reference Environments

Designed for librarians, Question Master (QM) (at http://purl.org/net/Question_Master) is a decision-support system automating some of the more routine, fact-type reference questions encountered in libraries. A series of Web pages guides librarians through a set of clarifying questions before making recommendations of an appropriate electronic or relevant print resource from WorldCat, the OCLC Online Union Catalog. The goal is to improve the accuracy of reference transactions, which in turn should lead to increased end-user satisfaction. Based on usability studies of QM’s biographical module, this study found that although the system already was easy to use, its usability could be improved in several ways. Its ability to answer questions was 100 percent, with an accuracy rate of 66 percent compared to Weil’s 64 percent accuracy. In addition, QM accuracy was substantially better than most reported studies of real reference environments and certainly better than the Internet results of 20 percent for HotBot and 30 percent for AltaVista.
On choosing hell

Most contemporary philosophers who defend the compatibility of hell with the divine goodness do so by arguing that the damned freely choose hell. Thomas Talbott denies that such a choice is possible, on the grounds that God in his goodness would remove any 'ignorance, deception, or bondage to desire' which would motivate a person to choose eternal misery. My strategy is to turn the tables on Talbott and ask why God would not remove the motives we have for any sin whatsoever. I argue that two plausible answers to this question also show why God would not remove our motives for choosing hell.
Dynamic Targeted Pricing in B2B Settings

We model the multifaceted impact of pricing decisions in B2B contexts and show how a seller can develop optimal inter-temporal targeted pricing strategies to maximize long-term customer value. We empirically model the B2B customer’s purchase decisions in an integrated fashion. In order to facilitate targeting and to capture the short and long-term dynamics of B2B customer purchasing, our modeling framework weaves together in a hierarchical Bayesian manner, multivariate copulas, a non-homogeneous hidden Markov model, and control functions for price endogeneity. We estimate our model on longitudinal transactions data from an aluminum retailer. We find that customers in our dataset can be best represented by two latent states - a “vigilant” state characterized by heightened price sensitivity and a cautious approach to ordering, and a more “relaxed” state. The seller’s pricing decisions can transition customers between these two states. An optimal dynamic and targeted pricing strategy based on our model suggests a 52% improvement in profitability compared to the status quo. Furthermore, a counterfactual analysis which examines the optimal policy under fluctuating commodity prices reveals that the seller should pass much of the costs to customers when commodity prices increase, but hoard most of the profit when commodity prices (seller’s costs) decrease.
Dissecting Complex Epigenetic Alterations in Breast Cancer Using CpG Island Microarrays

It is now clear that aberrant DNA methylation observed in cancer cells is not restricted to a few CpG islands, but affects multiple loci. When this epigenetic event occurs at the 5'-end of the regulatory region of genes, it is frequently associated with transcriptional silencing. To investigate further this widespread event in the tumor genome, we developed a novel microarray containing 7776 short GC-rich tags tethered to glass slide surfaces. This DNA chip was used to study 17 paired tissues of breast tumors and normal controls. Amplicons, representing differential pools of methylated DNA fragments between tumors and normal controls, were cohybridized to the microarray panel. Hypermethylation of multiple CpG island loci was then detected in a two-color fluorescence system. Approximately 1% (on average, 83 loci) of these CpG islands examined were hypermethylated in this patient group. Hierarchical clustering segregated these tumors based on their methylation profiles and identified a group of CpG island loci that corresponds to the hormone-receptor status of breast cancer. This observation was independently confirmed by examining a single locus, the promoter of the human glypican 3 gene, which was predominately hypermethylated in the hormone receptor-negative tumors. Our findings support the notion that hypermethylation of critical CpG island loci influences cancer development and produces distinct epigenetic signatures for particular tumor subtypes.
Utilizing infrared for improved FET channel temperature prediction

Measuring channel temperature in FETs (field effect transistors) is challenging due to the submicron dimensions of the gate fingers. Among the simplest techniques for temperature measurement is Infrared (IR) microscopy. However, IR is suffers from limited spatial resolution (≫5–10 microns). This paper presents a model for the channel temperature prediction based on IR techniques by reversing the spatial averaging inherent in IR microscopy.
How the Purkinje system determines the ventricular activation sequence

Conduction of the cardiac action potential in a spatially and temporally defined excitation sequence involves regional differences in cell membrane properties and intercellular coupling. This produces a sequence which in some regions is nearly continuous while other regions have discontinuous conduction. The Purkinje-Ventricular junction sites on the endocardial surface seem specifically designed to use discontinuous conduction as a means of effectively increasing the spread of activation through the endocardial surface while preserving a high safety factor for conduction. We present a historical survey of studies on this junctional region. Because of the specialized nature of the action potential properties of the Purkinje and ventricular as well as the localized electrical coupling, these sites may serve to originate arrhythmias as regions of after-depolarizations or may serve as important sites within endocardial reentrant circuits. In addition, the changes in the spatial pattern of junctional conductance following myocardial ischemia may produce other sites within the atrium or ventricle with properties of discontinuous conduction.
High Bandwidth Resonant Radio Frequency Circuit for Lipid Bilayer Detection

Research on ion channels are traditionally performed in the DC regime. Only a few attempts having been made to conduct RF measurements for probing ion channel properties. We present here simulations and subsequent measurements of an integrated coplanar waveguide and microfluidic tank circuit detecting bilayer formation. We observe a 5 MHz shift in resonant frequency and a 1.4 dB shift in amplitude when a lipid bilayer is formed. These measurements allow for in-vitro radio frequency recordings with nanosecond readout times. The designed structure also enables the incorporation of simultaneous RF and DC recordings from lipid bilayer embedded proteins such as ion channels.
A study of auditory modeling and processing for speech signals

We study a modified version of a computational model of the human peripheral and central auditory system (Wang, K. and Shamma, S.A., 1995; Yang, X. et al., 1992), and examine the validity of its output from two practical perspectives. One considers the well-known Mel-frequency cepstral coefficients (MFCC) as an approximate representation of the physiology-based early auditory processing result. The other allows the derivation of feature vectors from the dimension expanded cortical response of the central auditory system for use in a conventional phoneme recognition task. In addition to confirming the relevancy of the model under an existing statistical speech recognition framework, we conduct a preliminary study of the cortical response in connection with known physiological studies, to find new possibilities in using the auditory model to perform cognitive functions based on a better understanding of the human auditory system. In particular, the cortical response may be a place-coded data set where sounds are categorized according to the regions containing their most distinguishing features. The results of this study encourage us to develop hierarchical, detection-based methods in which this mechanism may be utilized to simulate a variety of human perceptual and cognitive functions.
Chemical Communication in Decapod Shrimps: The Influence of Mating and Social Systems on the Relative Importance of Olfactory and Contact Pheromones

Interest in chemoreception of decapod shrimps has been stimulated by observations indicative of sex pheromones, such as frenzied male searching and copulatory activity in the presence of premolt or recently postmolt reproductive females. Review of previous studies on shrimp mating behavior led to the formulation of hypotheses about the variation of chemical communication with mating and social systems. Penaeoidean and many caridean species are highly mobile and live in dense aggregations, resulting in frequent contacts among individuals. In such species, males are usually stimulated to copulatory behavior by apparent contact pheromones on the newly molted female’s exoskeleton, received by contact with the male’s antennal flagella. In species with temporary mate guarding, males search for premolt reproductive females, which release water soluble substances received by olfactory receptors (aesthetascs). Males guard females for some days until the female molt, after which mating occurs, followed by male abandonment to search for other females. In “neighborhoods of dominance” mating systems, it is the premolt parturial female that seeks out a large dominant male, stimulated by his olfactory pheromones. She is then guarded by the male, which will mate with her after her molt. In monogamous mate guarding species, males and females form permanent pairs, with the initial pairing perhaps mediated by sex pheromones emitted and perceived by both sexes. Olfactory sex pheromones are given off by females in many caridean species just after the molt, stimulating nearby males and ensuring mate finding. Recognition of pair partners or social (agonistic) status of an individual is chemically mediated in various decapod shrimps. The exact source and chemical composition of olfactory sex pheromones is still unknown, but both cuticular hydrocarbons and glycoproteins have been implicated as contact sex pheromones. Comparative studies with additional species are required to test these hypotheses about the form of chemical communication in different mating systems. Isolation and chemical identification of sex and individual-recognition pheromones is a major avenue of future research. Results of such studies may not only result in a greater understanding of chemoreception per se, but also may lead to commercial applications in shrimp fisheries and aquaculture.
Quasinormal modes of nearly extremal Kerr spacetimes: Spectrum bifurcation and power-law ringdown

We provide an in-depth investigation of quasinormal-mode oscillations of Kerr black holes with nearly extremal angular momenta. We first discuss in greater detail the two distinct types of quasinormal-mode frequencies presented in a recent paper [H. Yang et al., Phys. Rev. D 87 041502 (2013)]. One set of modes that we call “zero-damping modes” has vanishing imaginary part in the extremal limit and exists for all corotating perturbations (i.e. modes with azimuthal index m≥0). The other set (the “damped modes”) retains a finite decay rate even for extremal Kerr black holes and exists only for a subset of corotating modes. As the angular momentum approaches its extremal value, the frequency spectrum bifurcates into these two distinct branches when both types of modes are present. We discuss the physical reason for the mode branching by developing and using a bound-state formulation for the perturbations of generic Kerr black holes. We also numerically explore the specific case of the fundamental l=2 modes, which have the greatest astrophysical interest. Using the results of these investigations, we compute the quasinormal-mode response of a nearly extremal Kerr black hole to perturbations. We show that many superimposed overtones result in a slow power-law decay of the quasinormal ringing at early times, which later gives way to exponential decay. This exceptional early-time power-law decay implies that the ringdown phase is long lived for black holes with large angular momentum, which could provide a promising strong source for gravitational-wave detectors.
Fully constrained least squares linear spectral mixture analysis method for material quantification in hyperspectral imagery

Linear spectral mixture analysis (LSMA) is a widely used technique in remote sensing to estimate abundance fractions of materials present in an image pixel. In order for an LSMA-based estimator to produce accurate amounts of material abundance, it generally requires two constraints imposed on the linear mixture model used in LSMA, which are the abundance sum-to-one constraint and the abundance nonnegativity constraint. The first constraint requires the sum of the abundance fractions of materials present in an image pixel to be one and the second imposes a constraint that these abundance fractions be nonnegative. While the first constraint is easy to deal with, the second constraint is difficult to implement since it results in a set of inequalities and can only be solved by numerical methods. Consequently, most LSMA-based methods are unconstrained and produce solutions that do not necessarily reflect the true abundance fractions of materials. In this case, they can only be used for the purposes of material detection, discrimination, and classification, but not for material quantification. The authors present a fully constrained least squares (FCLS) linear spectral mixture analysis method for material quantification. Since no closed form can be derived for this method, an efficient algorithm is developed to yield optimal solutions. In order to further apply the designed algorithm to unknown image scenes, an unsupervised least squares error (LSE)-based method is also proposed to extend the FCLS method in an unsupervised manner.
Preemptive Use of Oral Ganciclovir to Prevent Cytomegalovirus Infection in Liver Transplant Patients: A Randomized, Placebo-Controlled Trial

The use of postdetection antiviral treatment of cytomegalovirus (CMV) as a strategy to prevent infection and disease in solid-organ transplant patients has not been evaluated by placebo-controlled trials. We carried out such a study in 69 patients who had received liver transplants and had positive results of CMV polymerase chain reaction within 8 weeks after transplantation but did not have concomitant CMV infection or disease. These patients were randomly assigned to receive placebo or oral ganciclovir for 8 weeks. CMV infection developed in 21% and disease developed in 12% of placebo recipients (P = .022), compared with 3% and 0%, respectively, among ganciclovir recipients (P = .003). Similarly, in the placebo arm, 55% and 36% of CMV-negative patients who received organs from CMV-positive donors developed CMV infection or disease, respectively (P = .02), compared with 11% and 0% of such patients in the ganciclovir arm (P <.01). Oral ganciclovir administered on CMV detection by PCR prevents CMV infection or disease after liver transplantation.
Charter schools, teacher labor market deregulation, and teacher quality : Evidence from the schools and staffing survey

This study uses teacher-level data from the Schools and Staffing Survey of 1999 to test whether teachers in charter schools have stronger academic backgrounds than their peers working in conventional public schools and whether state regulatory policies are associated with differences between public and public charter school teachers. Specifically, the authors estimate whether school type (public, public charter, independent private, private Catholic) is associated with the likelihood that a teacher attended a highly or most competitive undergraduate college. They find compelling evidence both that charter schools generally hire more teachers from more competitive undergraduate institutions than do conventional public schools and, furthermore, that relaxation of state teacher certification policies for charter schools increases the likelihood that charter schools hire teachers from more competitive undergraduate institutions. Findings are highly dependent on supply of teachers from competitive undergraduat...
Stress and chytridiomycosis: exogenous exposure to corticosterone does not alter amphibian susceptibility to a fungal pathogen.

Recent emergence and spread of the amphibian fungal pathogen, Batrachochytrium dendrobatidis (Bd) has been attributed to a number of factors, including environmental stressors that increase host susceptibility to Bd. Physiological stress can increase circulating levels of the hormone, corticosterone, which can alter a host's physiology and affect its susceptibility to pathogens. We experimentally elevated whole-body levels of corticosterone in both larval and post-metamorphic amphibians, and subsequently tested their susceptibility to Bd. Larvae of three species were tested (Anaxyrus boreas, Rana cascadae, and Lithobates catesbeianus) and one species was tested after metamorphosis (R. cascadae). After exposure to Bd, we measured whole-body corticosterone, infection, mortality, growth, and development. We found that exposure to exogenous corticosterone had no effect on Bd infection in any species or at either life stage. Species varied in whole-body corticosterone levels and exposure to corticosterone reduced mass in A. boreas and R. cascadae larvae. Exposure to Bd did not affect mortality, but had a number of sublethal effects. Acrossspecies,larvaeexposedtoBdhadhighercorticosteronelevelsthanunexposedlarvae,butthe opposite pattern was found in post-metamorphic R. cascadae. Bd exposure also increased larval length in all species and increased mass in R. cascadae larvae. Our results indicate that caution is warranted in assuming a strong link between elevated levels of corticosterone and disease susceptibility in amphibians. The role of physiological stress in altering Bd prevalence in amphibian populations is likely much more complicated than can be explained by examining a single "stress" endpoint. J. Exp. Zool. 321A:243-253, 2014. © 2014 Wiley Periodicals, Inc. How to cite this article: Searle CL, Belden LK, Du P, Blaustein AR. 2014. Stress and chytridiomycosis: Exogenous exposure to corticosterone does not alter amphibian susceptibility to a fungal pathogen. J. Exp. Zool. 321A:243-253.
Attention During Lectures: Beyond Ten Minutes

Many authors claim that students' attention declines approximately 10 to 15 min into lectures. To evaluate this claim, we reviewed several types of studies including studies of student note taking, observations of students during lectures, and self-reports of student attention, as well as studies using physiological measures of attention. We found that the research on which this estimate is based provides little support for the belief that students' attention declines after 10 to 15 min. Most studies failed to account for individual differences in attention. Our findings indicate that instructors should take into account individual differences in student attention when lecturing and determine whether students are recording the relevant content of the lecture in their notes.
A new family of soft equalizers in broadband wireless MIMO systems

We consider the problem of channel equalization in broadband wireless multiple-input multiple-output (MIMO) systems over frequency-selective fading channels, based on the sequential Monte Carlo (SMC) sampling techniques for Bayesian inference. Built on the technique of importance sampling, the stochastic sampler generates weighted random MIMO symbol samples; whereas the deterministic sampler, a heuristic modification of the stochastic counterpart, recursively performs exploration and selection steps in a greedy manner in both space and time domains. Such a space-time sampling scheme is very effective in combating both intersymbol interference and cochannel interference caused by frequency-selective channel and multiple transmit and receiver antennas. Finally, computer simulation results are provided to demonstrate that the proposed sampling-based MIMO equalizers significantly outperform the decision-feedback MIMO equalizers with comparable computational complexity.
On the limitations of multivariate phase-type families

Consider a finite set of independent phase-type random variables. Suppose that we construct a random vector, each component of which is a total over a subset of this set. In 1984, D. Assaf et al. conjectured that such a vector need not have a multivariate phase-type distribution, and they provided a sufficient condition for the distribution to be of that type. We confirm their conjecture, and show that their sufficient condition is also essentially necessary. An open question of V. G. Kulkarni is whether or not his extension of the multivariate phase-type family is closed under familiar operations arising in reliability. This question is answered here in the negative.
New Sugar Mitomycin C Analogues: Preparation, Murine P388 Antitumor Activity, and Leukopenia Induction

Abstract Four new sugar:mitomycin C derivatives were synthesized by coupling of N-1 of mitomycin C with tetra- O -acetylglucopyranosyl isothiocyanate and 3,4,6-tri- O -acetyl-2-( N -acetylamino)-2-deoxyglucopyranosyl isothiocyanate. Conversion of each derivative to its water- soluble analogue was achieved by deacetylation, using saturated NH 3 :CH 3 0H. Antitumor activity, assessed using the in vivo murine P388 ascitic leukemia system, demonstrated efficacy comparable with the parent mitomycin C. However, unlike the highly myelosuppressive parent drug, optimal antitumor activity is achieved at doses which produce only limited leukopenia.
Partitioned vector quantization: application to lossless compression of hyperspectral images

A novel design for a vector quantizer that uses multiple codebooks of variable dimensionality is proposed. High dimensional source vectors are first partitioned into two or more subvectors of (possibly) different length and then, each subvector is individually encoded with an appropriate codebook. Further redundancy is exploited by conditional entropy coding of the subvectors indices. This scheme allows practical quantization of high dimensional vectors in which each vector component is allowed to have different alphabet and distribution. This is typically the case of the pixels representing a hyperspectral image. We present experimental results in the lossless and near-lossless encoding of such images. The method can be easily adapted to lossy coding.
Establishing a sonority hierarchy in American Sign Language: the use of simultaneous structure in phonology

The purpose of this paper is to help define and limit the role that temporal ordering plays in morphophonemic representation, syllable structure and phrases in American Sign Language (ASL). First, I will list the ways in which temporal ordering plays a role in morphophonemic structures. Second, I will show that temporal ordering plays a limited role in ASL phrases. Third, I will argue that neither temporal ordering nor segmentation plays a role in syllables, and the bulk of this paper will be devoted to motivating this syllable template. Stokoe (1960) and Stokoe et al. (1965) proposed that ASL is organised according to simultaneous phonemes, but since Liddell (1984) the importance of temporally ordered structure in sign structure has been emphasised by many researchers (Liddell & Johnson 1989; Sandler 1986, 1989; Perlmutter 1990, 1992; Corina 1990a, b; to name a few).
Where in the World Is Carmen Sandiego (and Is She a Software Engineer)

Recent conversations pertaining to licensure of software engineers in the US and offshoring had me thinking about Carmen again. I wondered how well she would have fared if her secret agent cover was as a software guru. Would she be able to pass as a software engineer in several different countries-for example, in the US, India, Malaysia, Argentina, and Ireland? Are there differences in how software engineering is practiced in different cultures that are so profound that even a super spy, expert at mimicry and disguise, couldn't fool her colleagues? The answers to these questions have important implications for the transnational practice of software engineering, for outsourcing and offshoring policy and strategy, and even for national security.
Formoterol Restores Mitochondrial and Renal Function after Ischemia-Reperfusion Injury

Mitochondrial biogenesis may be an adaptive response necessary for meeting the increased metabolic and energy demands during organ recovery after acute injury, and renal mitochondrial dysfunction has been implicated in the pathogenesis of AKI. We proposed that stimulation of mitochondrial biogenesis 24 hours after ischemia/reperfusion (I/R)-induced AKI, when renal dysfunction is maximal, would accelerate recovery of mitochondrial and renal function in mice. We recently showed that formoterol, a potent, highly specific, and long-acting β2-adrenergic agonist, induces renal mitochondrial biogenesis in naive mice. Animals were subjected to sham or I/R-induced AKI, followed by once-daily intraperitoneal injection with vehicle or formoterol beginning 24 hours after surgery and continuing through 144 hours after surgery. Treatment with formoterol restored renal function, rescued renal tubules from injury, and diminished necrosis after I/R-induced AKI. Concomitantly, formoterol stimulated mitochondrial biogenesis and restored the expression and function of mitochondrial proteins. Taken together, these results provide proof of principle that a novel drug therapy to treat AKI, and potentially other acute organ failures, works by restoring mitochondrial function and accelerating the recovery of renal function after injury has occurred.
Preparation Of Near-Infrared-Labeled Targeted Contrast Agents For Clinical Translation

Targeted fluorophore-labeled contrast agents are moving toward translation to human surgical use. To prepare for future clinical use, we examined the performance of potential ligands targeting the epidermal growth factor receptor, α5β3 integrins, and GLUT transporters for their suitability as directed contrast agents. Each agent was labeled with IRDye 800CW, and near-infrared dye with excitation/emission wavelengths of 789/805 nm, which we determined had favorable toxicity characteristics. The probe molecules examined consisted of Affibodies, nanobodies, peptides, and the sugar 2-deoxy-D-glucose. Each probe was tested for specific and non-specific binding in cell based assays. All probe types showed good performance in mouse models for detecting either spontaneous tumors or tumor xenografts in vivo. Each of the probes tested show promise for future human clinical studies.
John Rae on Economic Development: A Note

Introduction, 393. — I. Rae's theory, 395. — II. Application of Rae's theory, 402. — III. Conclusion, 405. "He formulated the economic theory of new countries.…" —R. Warren James1
Understanding and responding to disparities in HIV and other sexually transmitted infections in African Americans.

Although these health disparities are not unique to STIs; their nature, pattern, and distribution are complex. This complexity is not solely a result of individual risk behaviours. Increasing evidence indicates that disease epidemics, and, consequently, disparities in morbidity rates, are outcomes of the functioning of systems.
Activation of magnesium rich minerals as carbonation feedstock materials for CO2 sequestration

Abstract Mineral carbonation, the reaction of magnesium-rich minerals such as olivine and serpentine with CO 2 to form stable mineral carbonates, is a novel and promising approach to carbon sequestration. However, the preparation of the minerals prior to carbonation can be energy intensive, where some current studies have been exploring extensive pulverization of the minerals below 37 μm, heat treatment of minerals up to 650 °C, prior separation of CO 2 from flue gases, and carbonation at high pressures, temperatures and long reaction times of up to 125 atm, 185 °C and 6 h, respectively. Thus, the objective of the mineral activation concept is to promote and accelerate carbonation reaction rates and efficiencies through surface activation to the extent that such rigorous reaction conditions were not required. The physical activations were performed with air and steam, while chemical activations were performed with a suite of acids and bases. The parent serpentine, activated serpentines, and carbonation products were characterized to determine their surface properties and assess their potential as carbonation minerals. The results indicate that the surface area of the raw serpentine, which is approximately 8 m 2 /g, can be increased through physical and chemical activation methods to over 330 m 2 /g. The chemical activations were more effective than the physical activations at increasing the surface area, with the 650 °C steam activated serpentine presenting a surface area of only 17 m 2 /g. Sulfuric acid was the most effective acid used during the chemical activations, resulting in surface areas greater than 330 m 2 /g. Several of the samples produced underwent varying degrees of carbonation. The steam activated serpentine underwent a 60% conversion to magnesite at 155 °C and 126 atm in 1 h, while the parent sample only exhibited a 7% conversion. The most promising results came from the carbonation of the extracted Mg(OH) 2 solution, where, based on the amount of magnesium recovered in the precipitate after the 3.5 h reaction, the carbonation efficiency was estimated to be at least 53%. Reaction products included several hydrated magnesium carbonate compounds. The carbonation reaction was conducted at ambient temperature, 20 °C, and low pressure, 45 atm.
OPTIMAL PRE-COMMITMENT IN MACROECONOMIC POLICY: A GAME THEORETIC ANALYSIS OF FISCAL POLICY

This paper proposes a new solution to the problem of time inconsistency that arises in dynamic policy games played between the government and the public. In a Stackelberg game, a subgame-perfect equilibria is found in which members of the public employ trigger strategies in response to a sequence of policies chosen by the government. The government's precommitment to a particular policy is determined endogenously as part of its optimal strategy. In a simple political model of fiscal policy, the proposed equilibrium is used to show why a government will tolerate a rise in debt well above its targeted level. Copyright 1990 by Royal Economic Society.
Selective venography versus nonselective venography before vena cava filter placement: evidence for more, not less.

Abstract Objective We undertook this study to determine whether additional use of selective venography, compared with nonselective venography alone, reveals more abnormal anatomic venous findings that lead to changes in vena cava filter (VCF) position. Methods From January 1998 to June 2002, 94 patients underwent VCF placement by vascular surgeons at a university tertiary care center. Indications, techniques, decision analysis, and complications were reviewed. Nonselective venography and selective venography of the inferior vena cava (IVC) were evaluated for image quality, abnormal findings, aberrant anatomy, and the anatomic relationship of vertebral bodies to major venous tributaries. Results Absolute and relative indications for VCF placement were 44% and 56%, respectively. Jugular, femoral, and subclavian vein approach was used in 47%, 47%, and 6% of patients, respectively. Seventy-three percent of VCFs were placed in the catheterization laboratory, 21% in the operating room, and 5% at the bedside. Nonselective venography was performed in 80 patients (85%), of whom 44% had undergone selective venography. At nonselective venography plus selective venography 7.5% of patients had an abnormal finding (IVC compression, n=3; IVC thrombus, n=2; tortuosity, n=1). Similarly, 17.5% of patients had aberrant anatomy (accessory renal vein, n=8; IVC duplication, n=3; large low right gonadal vein, n=2; megacava, n=2). Nonselective venography plus selective venography demonstrated that 16% of VCFs required a major change in position, 10% of which were placed above the renal veins. Compared with nonselective venography alone, selective venography enabled detection of significantly more abnormal and aberrant findings (9% vs 49%; P P = .003). In one patient in the series, a VCF was malpositioned in the iliac vein with intravascular ultrasound visualization. Conclusion When nonselective venography plus selective venography were performed, 23% of patients had either an abnormal finding or aberrant anatomy, and most of these required a major change in VCF position. Nonselective venography plus selective venography redefines the criterion standard and, because of limitations of other methods of vena cava visualization for VCF deployment, should be performed in most patients.
Thermal and mechanical properties and water absorption of sodium dodecyl sulfate-modified soy protein (11S) †

The thermal and mechanical properties and water absorption of sodium dodecyl sulfate (SDS)-modified 11S soy protein and molded plastics made from it were studied using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), mechanical tests, and scanning electron microscopy (SEM). The DSC results showed that both the temperature and enthalpy of thermal denaturation of modified 11S solutions decreased as the SDS concentration increased. Nonfreezing water of the modified 11S solution had a minimum value at 1.0% SDS. The ordered structure of SDS-modified 11S protein was recovered and/or newly formed during the freeze-drying process. Both DSC and DMA results showed that SDS was a plasticizer of 11S, and the glass transition temperature of modified 11S plastics decreased with increasing SDS concentration. Both the tensile strength and elongation of modified 11S plastics first decreased and then increased as the SDS concentration increased, and 5.0% SDS-modified 11S plastic had the highest tensile strength and elongation. The SEM observations supported these results. A water-absorption test showed a reduction in the water resistance of 11S plastics after SDS modification. The rate of water absorption increased with increasing SDS concentration. The hydrophobic interaction between SDS molecules and 11S protein was found to have important effects on the thermal and mechanical properties and the water absorption of 11S plastics. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 166–175, 2001
Initial results of a novel pre-deposition seeding technique for achieving an ultra-high nucleation density for CVD diamond growth

Abstract The unique thermal properties of diamond, along with the ability to deposit it over large areas, make it an appropriate candidate for electronic packaging and other thermal management applications. In a recent exploration, our group observed defects in diamond films, referred to as “microcavities”. Microcavities are essentially voids in CVD diamond resulting from the growth of randomly-oriented grains. These microcavities present serious challenges to the fabrication of high-density electronic packages when they appear at the surface of the film/substrate. Two approaches for solving the microcavity problem were explored; (1) “planarization by filling” and (2) enhancement of the nucleation density. Results of the first approach have been reported elsewhere. The latter approach, which is the subject of this paper, is based on an electrostatic seeding technique for uniformly depositing nanometer size diamond particles over the entire surface of any material of any shape to serve as nucleation sites for diamond growth. This approach to initiating diamond growth is inexpensive and simple. The resulting films are very dense, and both the number and size of the microcavities are significantly reduced. Details of the seeding technique and resulting diamond films, characterized using SEM, will be discussed.
Die Überprüfung der Forschungsthesen

Anliegen dieses Kapitel ist es, die Soziale Identitat empirisch bei der schulischen Transition zu ermitteln, zum anderen sollen die erstellten Ubergangsmodelle vorgestellt werden. Eingangs folgt eine kurze Erlauterung und Begrundung der, in dieser Arbeit eingesetzten Analysen. Danach werden die, im theoretischen Rekurs erstellten Thesen anhand der entwickelten Pfadmodelle und den jeweils relevanten Variablen gepruft.
Predicting Return on Investment In Sport Sponsorship

ABSTRACT Although the benefits sought by engaging in non-traditional marketing tactics such as sponsorship are well documented, determining return on investment (ROI) remains an evolving science. To advance ROI analysis in sponsorship, the authors of this study utilized data on sponsorship prices and the televised exposure of sponsors in Formula One motor racing. Results validated a strong link between team performance and sponsors9 realized brand exposure and price paid. Price also was influenced by sponsorship level, functional congruence and, at the lowest level of sponsorship, shared nationality. Finally, overall the authors found that positive ROI is more likely for sponsors of better performing teams, for sponsors that affiliate at a high level, and for sponsors outside the automotive industry.
Human long-term culture initiating cells are sensitive to benzylguanine and 1,3-bis(2-chloroethyl)-1-nitrosourea and protected after mutant (G156A) methylguanine methyltransferase gene transfer

Human hematopoietic progenitors express low levels of O6-alkylguanine-DNA alkyltransferase and are sensitive to 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), particularly following O6-benzylguanine (BG)-mediated O6-alkylguanine-DNA alkyltransferase inhibition. Expression of the BG-resistant mutant (G156A) methylguanine methyltransferase (ΔMGMT) gene in hematopoietic cells confers resistance to BG and BCNU. Because BCNU targets both early and late human hematopoietic cells and results in prolonged and cumulative myelosuppression, we attempted to protect early hematopoietic progenitors (long-term culture initiating cells (LTC-ICs)) by retroviral-mediated transfer of the ΔMGMT gene. A total of 33–56% of LTC-ICs were transduced with MFG-ΔMGMT retrovirus as determined by evidence of provirus in secondary colony-forming units at 5 weeks of culture under conditions optimal for the survival and proliferation of early hematopoietic progenitors. The addition of flt-3 ligand to cultures increased the transduction rate of LTC-ICs. Furthermore, 17.8 ± 8.1% of ΔMGMT-transduced LTC-ICs survived doses of BG and BCNU; these doses allowed the survival of only 0–1% of untransduced LTC-ICs. This finding compares favorably with the 8–12% of CD34+ cell-derived colony-forming units that we previously showed became resistant to BG and BCNU after ΔMGMT gene transfer. Thus, ΔMGMT transduction of human early hematopoietic progenitor LTC-ICs confers resistance to BG and BCNU and may allow transduced LTC-ICs selective survival and enrichment over untransduced cells in patients undergoing BG and BCNU chemotherapy.
Foreign direct investment in the Dominican Republic: consequences and recommendations for sustainable growth

This research, using a production function methodology, examines the effects of international trade and foreign direct investment (FDI) liberalization policies on the economy of the Dominican Republic during the 1990s. Most of the FDI was in the free trade zone (FTZ) sector. The results have important ramifications on current policies to promote sustainable economic growth. The econometric results indicate evidence of unbalanced growth characterized by regional and technological dualism: (a) an efficient FTZ sector, highly dependent on FDI, and operating under increasing returns to scale, and (b) a relatively inefficient primary/secondary sector operating under decreasing returns to scale. These growth strategies fail to establish economic linkages between different economic sectors; also they focus on the development of the FTZ sector whose contribution to GDP averages only about 3 %. Policies to promote sustainable growth necessitate strategies to develop and diversify the primary/service sectors. Importantly, recently revised agreements on international trade will lessen the competitiveness of the FTZ sector.
Development of Functional Microfold (M) Cells from Intestinal Stem Cells in Primary Human Enteroids

Background & Aims Intestinal microfold (M) cells are specialized epithelial cells that act as gatekeepers of luminal antigens in the intestinal tract. They play a critical role in the intestinal mucosal immune response through transport of viruses, bacteria and other particles and antigens across the epithelium to immune cells within Peyer’s patch regions and other mucosal sites. Recent studies in mice have demonstrated that M cells are generated from Lgr5+ intestinal stem cells (ISCs), and that infection with Salmonella enterica serovar Typhimurium increases M cell formation. However, it is not known whether and how these findings apply to primary human small intestinal epithelium propagated in an in vitro setting. Methods Human intestinal crypts were grown as monolayers with growth factors and treated with recombinant RANKL, and assessed for mRNA transcripts, immunofluorescence and uptake of microparticles and S. Typhimurium. Results Functional M cells were generated by short-term culture of freshly isolated human intestinal crypts in a dose- and time-dependent fashion. RANKL stimulation of the monolayer cultures caused dramatic induction of the M cell-specific markers, SPIB, and Glycoprotein-2 (GP2) in a process primed by canonical WNT signaling. Confocal microscopy demonstrated a pseudopod phenotype of GP2-positive M cells that preferentially take up microparticles. Furthermore, infection of the M cell-enriched cultures with the M cell-tropic enteric pathogen, S. Typhimurium, led to preferential association of the bacteria with M cells, particularly at lower inoculum sizes. Larger inocula caused rapid induction of M cells. Conclusions Human intestinal crypts containing ISCs can be cultured and differentiate into an epithelial layer with functional M cells with characteristic morphological and functional properties. This study is the first to demonstrate that M cells can be induced to form from primary human intestinal epithelium, and that S. Typhimurium preferentially infect these cells in an in vitro setting. We anticipate that this model can be used to generate large numbers of M cells for further functional studies of these key cells of intestinal immune induction and their impact on controlling enteric pathogens and the intestinal microbiome.
Study on preparation of soybean insulating oil by partial methanol transesterification

Partial methanol transesterification soybean insulating oil product was prepared by controlling the reaction condition.The advantages of both refined oil and methyl ester oil products in flash point,solidifying point and viscosity,and those properties are very adjustable with different conversion ratios.Influence of process conditions on transesterification conversion ratio was studied by single factor experiment and central composite design of response surface methodology.A quadratic model was established which quantified the relationship between conversion ratio and the amount of catalyst,alcohol-oil molar ratio,reaction time and temperature.Experimental results showed that the model was quite accurate and applicable to optimize various process conditions in conversion ratios of 20%-95%,the relative standard deviation less than 1%.
Genes involved in stress response and alcohol use among high-risk African American youth.

ABSTRACTBackground: Genetic and environmental factors influence substance use behaviors in youth. One of the known environmental risk factors is exposure to life stressors. The aim of this project is to study the interaction between NR3C1 and CRHBP, genes thought to be involved in stress pathways, exposure to stressful life events, and adolescent alcohol use/misuse. Methods: The sample included 541 African American individuals (ages 13–18) from the Genes, Environment, and Neighborhood Initiative, a subset of the Mobile Youth Survey sample from whom DNA and more extensive phenotypic data were collected. Participants were selected from high-poverty neighborhoods in Mobile, Alabama, with potential exposure to a variety of extreme life stressors. Results: A measure of stressful life events was significantly predictive of alcohol use/misuse. In addition, this association was significantly dependent upon the number of putative risk variants at rs1715749, a single-nucleotide polymorphism (SNP) in CRHBP (P ≤ .006...
The Other Global Powers: France, Spain, Russia/the Soviet Union, Germany, and Japan

The last two chapters have described the winners in the 500-year struggle for naval predominance and political-military ascendancy in the global system. In the present chapter, the focus shifts to the ‘also-ran’ competitors for global power — France, Spain, Russia/the Soviet Union, Germany, and Japan — who lost or — at least in the case of the Soviet Union — who have yet to win their struggles with the world powers. We shall consider in order of ‘seniority’ defined as ‘years in global status’ between 1494 and 1983: France (451); Spain (315); Russia/the USSR (232); Germany (75); and Japan (75). As in Chapter 8, the emphasis will be placed on generating brief synopses of national naval developments as a prelude to the provision of more detailed information on each global power’s annual number of capital warships.