The WALRAS Algorithm: A Convergent Distributed Implementation of General Equilibrium Outcomes

The WALRAS algorithm calculates competitive equilibria via a distributed tatonnement-like process, in which agents submit single-good demand functions to market-clearing auctions. The algorithm is asynchronous and decentralized with respect to both agents and markets, making it suitable for distributed implementation. We present a formal description of this algorithm, and prove that it converges under the standard assumption of gross substitutability. We relate our results to the literature on general equilibrium stability and some more recent work on decentralized algorithms. We present some experimental results as well, particularly for cases where the assumptions required to guarantee convergence do not hold. Finally, we consider some extensions and generalizations to the WALRAS algorithm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44346/1/10614_2004_Article_137532.pd

STEM Initiatives: Stimulating Students to Improve Science and Mathematics Achievement

The article focuses on how concepts in science, technology education, and mathematics show powerful relationships when it comes to student learning. Learning theorists believe that, through designed learning environments (contexts) and learning with hands-on projects, new knowledge can not only be learned, but learned in such a way that the knowledge can be transferred for other applications. Scholars in the applied sciences (school science, technology, and mathematics) believe that these subjects have transfer among themselves and that engineering activities can establish the contexts to learn these subjects, plus aid in the transfer of knowledge. This collaborative movement is referred to as STEM — integrating instruction in science, technology education, engineering, and mathematics. For more information on the national standards, conduct a web search for National Science Education Standards (1996), Standards for Technological Literacy: Content for the Study of Technology (2000/2002), and Principles and Standards for School Mathematics, (2000)

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ABSTRACT. Objective. To determine whether men with gout may have an increased prevalence of erectile dysfunction (ED) as compared with men without gout. Methods. In this cross-sectional study, men aged 18-89 presenting to the rheumatology clinic between August 26, 2010, and May 13, 2013, were Erectile dysfunction (ED) is common in the general population, affecting about 50% of 40-to 70-year-old men 1 . The National Institutes of Health Consensus Development statement defined ED as the "inability of the male to attain and maintain erection of the penis sufficient to permit satisfactory sexual intercourse" 2 . The likelihood of ED increases with age, but is not an inevitable consequence of aging 2 . The importance of cardiovascular (CV) disease (CVD) as an underlying cause of ED is well established 3,4 . This is not surprising because CVD and ED share mutual risk factors such as diabetes mellitus (DM), hypertension (HTN), advanced age, hypercholesterolemia, obesity, metabolic syndrome, certain medications such as antidepressants, and tobacco abuse New evidence shows that hyperuricemia and inflammation may be independent risk factors for ED in addition to the established ones. In a recent study by Solak, et al 7 , of 312 men who underwent an exercise stress test because of chest pain, each 1 mg/dl increase in serum urate (SU) was associated with a 31% increased risk of ED. Compared with patients in the first quartile of SU level, those in the fourth quartile had a 2.6 times increased risk of ED. However, in an adjusted analysis for traditional CV risk factors, the relationship with SU was no longer significant. Another recent study, by Salem, et al 8 , evaluated SU level and the distribution of potential ED risk factors in 251 men with newly diagnosed ED versus 252 age-matched controls without ED. A significant difference was found between mean SU levels in men with ED (6.12 mg/dl) versus men without ED (4.97 mg/dl). The men in the highest tertile of SU level had a 6-fold increased risk of ED compared with men in the lowest tertile. Each 1 mg/dl increase in SU level was associated with a 2-fold increased risk of ED. Inflammation, too, plays an important role in ED 9,10 . Low levels of interleukin 6 (IL-6) and fibrinogen exclude the presence of ED in patients with coronary artery disease (CAD) or with unfavorable risk factor

Rhodacyanine Derivative Selectively Targets Cancer Cells and Overcomes Tamoxifen Resistance

MKT-077, a rhodacyanine dye, was shown to produce cancer specific cell death. However, complications prevented the use of this compound beyond clinical trials. Here we describe YM-1, a derivative of MKT-077. We found that YM-1 was more cytotoxic and localized differently than MKT-077. YM-1 demonstrated this cytotoxicity across multiple cancer cell lines. This toxicity was limited to cancer cell lines; immortalized cell models were unaffected. Brief applications of YM-1 were found to be non-toxic. Brief treatment with YM-1 restored tamoxifen sensitivity to a refractory tamoxifen-resistant MCF7 cell model. This effect is potentially due to altered estrogen receptor alpha phosphorylation, an outcome precipitated by selective reductions in Akt levels (Akt/PKB). Thus, modifications to the rhodocyanine scaffold could potentially be made to improve efficacy and pharmacokinetic properties. Moreover, the impact on tamoxifen sensitivity could be a new utility for this compound family

Magnetic Core Loss of Ultrahigh Strength FeCo Alloys

Hiperco® 50 alloy heat treated between 450 and 650 °C exhibits superior mechanical properties. We report the measurements of the ac core loss at various frequencies up to 4500 Hz of the Hiperco® 50 alloy samples annealed at 450 and 650 °C. The 650 °C annealed specimens have lower ac core loss than the 450 °C annealed ones. The total core loss, consisting of contributions from hysteresis core loss and eddy-current core loss, depends on the frequency f as af+bf2. The eddy current loss of a single laminate is minor compared to the hysteresis loss

Hard-core Yukawa model for two-dimensional charge stabilized colloids

The hyper-netted chain (HNC) and Percus-Yevick (PY) approximations are used to study the phase diagram of a simple hard-core Yukawa model of charge-stabilized colloidal particles in a two-dimensional system. We calculate the static structure factor and the pair distribution function over a wide range of parameters. Using the statics correlation functions we present an estimate for the liquid-solid phase diagram for the wide range of the parameters.Comment: 7 pages, 9figure

Record Maximum Oscillation Frequency in C-face Epitaxial Graphene Transistors

The maximum oscillation frequency (fmax) quantifies the practical upper bound for useful circuit operation. We report here an fmax of 70 GHz in transistors using epitaxial graphene grown on the C-face of SiC. This is a significant improvement over Si-face epitaxial graphene used in the prior high frequency transistor studies, exemplifying the superior electronics potential of C-face epitaxial graphene. Careful transistor design using a high {\kappa} dielectric T-gate and self-aligned contacts, further contributed to the record-breaking fmax

A BAC-based physical map of Brachypodium distachyon and its comparative analysis with rice and wheat

<p>Abstract</p> <p>Background</p> <p><it>Brachypodium distachyon </it>(<it>Brachypodium</it>) has been recognized as a new model species for comparative and functional genomics of cereal and bioenergy crops because it possesses many biological attributes desirable in a model, such as a small genome size, short stature, self-pollinating habit, and short generation cycle. To maximize the utility of <it>Brachypodiu</it>m as a model for basic and applied research it is necessary to develop genomic resources for it. A BAC-based physical map is one of them. A physical map will facilitate analysis of genome structure, comparative genomics, and assembly of the entire genome sequence.</p> <p>Results</p> <p>A total of 67,151 <it>Brachypodium </it>BAC clones were fingerprinted with the SNaPshot HICF fingerprinting method and a genome-wide physical map of the <it>Brachypodium </it>genome was constructed. The map consisted of 671 contigs and 2,161 clones remained as singletons. The contigs and singletons spanned 414 Mb. A total of 13,970 gene-related sequences were detected in the BAC end sequences (BES). These gene tags aligned 345 contigs with 336 Mb of rice genome sequence, showing that <it>Brachypodium </it>and rice genomes are generally highly colinear. Divergent regions were mainly in the rice centromeric regions. A dot-plot of <it>Brachypodium </it>contigs against the rice genome sequences revealed remnants of the whole-genome duplication caused by paleotetraploidy, which were previously found in rice and sorghum. <it>Brachypodium </it>contigs were anchored to the wheat deletion bin maps with the BES gene-tags, opening the door to <it>Brachypodium</it>-Triticeae comparative genomics.</p> <p>Conclusion</p> <p>The construction of the <it>Brachypodium </it>physical map, and its comparison with the rice genome sequence demonstrated the utility of the SNaPshot-HICF method in the construction of BAC-based physical maps. The map represents an important genomic resource for the completion of <it>Brachypodium </it>genome sequence and grass comparative genomics. A draft of the physical map and its comparisons with rice and wheat are available at <url>http://phymap.ucdavis.edu/brachypodium/</url>.</p

Preferential regulation of stably expressed genes in the human genome suggests a widespread expression buffering role of microRNAs

In this study, we comprehensively explored the stably expressed genes (SE genes) and fluctuant genes (FL genes) in the human genome by a meta-analysis of large scale microarray data. We found that these genes have distinct function distributions. miRNA targets are shown to be significantly enriched in SE genes by using propensity analysis of miRNA regulation, supporting the hypothesis that miRNAs can buffer whole genome expression fluctuation. The expression-buffering effect of miRNA is independent of the target site number within the 3'-untranslated region. In addition, we found that gene expression fluctuation is positively correlated with the number of transcription factor binding sites in the promoter region, which suggests that coordination between transcription factors and miRNAs leads to balanced responses to external perturbations

T-Violation in K+→μ+νγK^+ \to \mu^+ \nu \gamma Decay And Supersymmetry

Measurement of the transverse muon polarization $P^{\bot}_{\mu}$ in the $K^+ \rightarrow \mu^+\nu\gamma$ decay will be attempted for the first time at the ongoing KEK E246 experiment and also at a proposed BNL experiment. We provide a general analysis of how $P^{\bot}_{\mu}$ is sensitive to the physical $CP$-violating phases in new physics induced four-Fermi interactions, and then we calculate the dominant contributions to $P^{\bot}_{\mu}$ from squark family mixings in generic supersymmetric models. Estimates of the upper bounds on $P^{\bot}_{\mu}$ are also given. It is found that a supersymmetry-induced right-handed quark current from $W$ boson exchange gives an upper limit on $P^{\bot}_{\mu}$ as large as a few per cent, whereas with charged-Higgs-exchange induced pseudoscalar interaction, $P^{\bot}_{\mu}$ is no larger than a few tenths of a per cent. Possible correlations between the muon polarization measurements in $K^+ \rightarrow \mu^+\nu\gamma$ and $K^+ \rightarrow \pi^0\mu^+\nu$ decays are discussed, and distinctive patterns of this correlation from squark family-mixings and from the three-Higgs-doublet model are noted.Comment: Revtex, 29 pages including 4 epsf figure