bluuebunny/crossref_metadata_2025 huggingface dataset:
Mise en conformité sismique des ponts par isolation de la base – Application au pont Madrid au Québec
Authors: Guizani Lotfi , Chaallal Omar
Published: December 2010

Les nouvelles technologies basées sur l’isolation sismique connaissent un intérêt grandissant parmi les ingénieurs, compte tenu de l’économie sur le coût de la construction de l’ouvrage qu'elles offrent. Elles présentent également un avantage indéniable à long terme étant donné qu’elles préservent la fonctionnalité de l’ouvrage après séisme et éliminent le coût de reconstruction. Cet avantage revêt une importance capitale pour les ponts dits de secours qui doivent demeurer en service après le séisme. Cet article présente une méthodologie relative à l’isolation de la base des ponts existants dans un contexte de mise en conformité sismique. Cette démarche est motivée par l’intérêt grandissant de cette méthode, notamment depuis son adoption par la norme canadienne d’une part et d’autre part par le fait que les ingénieurs praticiens sont moins familiers avec les méthodes dynamiques non linéaires de conception. L’opportunité offerte aux auteurs de mettre en application cette technique pour la réfection de quelques ponts au Québec est une autre source de motivation. Les étapes de calcul parasismiques sont pourvues, et les résultats des analyses non linéaires relatives au pont Madrid sont présentés et discutés. L’article est destiné aux ingénieurs praticiens qui y trouveront un outil utile pour leurs projets en réhabilitation de ponts existants.
Numerical simulation of a secondary clarifier in a sewage treatment plant using modified Bingham model
Authors: Saffarian Mohammad Reza , Hamedi Mohammad Hossein , Shams Mehrzad
Published: December 2010

A numerical scheme for simulation of activated sludge sediment flow in a circular secondary clarifier is developed. The flow and settling processes are simulated, using the k–ε turbulence model on a two-dimensional axisymmetric and orthogonal grid. To incorporate the sedimentation of the activated sludge in the field of gravity, a convection–dispersion equation governing the mass transfer in the clarifier is extended. The computational domain includes the sludge blanket where the viscosity is affected by the rheological behavior of the sludge. The double-exponential equation is used to describe the dependence of the settling velocity on the solids concentration. The compression and consolidation process of the activated sludge is simulated by this equation. The experimental data provided by Weiss et al. show that the rheograms follow the Bingham law at low-shear rates. The modified Bingham model was introduced to overcome the blanket height overestimation problem with the results showing that the local sludge distribution in the clarifier has an excellent agreement with the concentration profile measurements by Weiss et al. (2007) and the sludge viscosity dominates the flow and sedimentation of activated sludge within the sludge blanket.
Improved intensity measures for probabilistic seismic demand analysis. Part 2: application of the improved intensity measures
Authors: Lin Lan , Naumoski Nove , Saatcioglu Murat , Foo Simon
Published: December 2010

This is the second of two companion papers on improved intensity measures of strong seismic ground motions for use in probabilistic seismic demand analysis of reinforced concrete frame buildings. The first paper discusses the development of improved intensity measures. This paper describes the application of the developed intensity measures in probabilistic seismic demand analysis. The application is illustrated on the three reinforced concrete frame buildings (4, 10, and 16-storey high) that were used in the first paper. This involved computations of the seismic responses of the structures and the seismic hazard using the improved intensity measures. The response and the hazard results were then combined by means of probabilistic seismic demand analysis to determine the mean annual frequencies of exceeding specified response levels due to future earthquakes (i.e., the probabilistic seismic demands). For the purpose of comparison, probabilistic seismic demand analyses were also conducted by employing the spectral acceleration at the fundamental structural periods (Sa(T1)) as an intensity measure, which is currently the most used in practice. It was found that the use of the improved intensity measures results in significantly lower seismic demands relative to those corresponding to the intensity measure represented by Sa(T1), especially for long period structures.
Experimental cyclic loading of concentric HSS braces
Authors: Haddad Madhar , Brown Tom , Shrive Nigel
Published: December 2010

During earthquake ground motion, diagonal braces in braced frames are subject to a series of cyclic loadings, alternately tension and compression. The brace can buckle and deform plastically, dissipating energy with damage accumulating in the steel. Eventually a crack may form and the brace fractures. To optimize energy dissipation, the effects of brace and gusset plate dimensions (thickness and length of the gusset plate, size of the brace, length of the brace), and material properties, on brace behaviour, need to be understood. Ten concentric bracing members, designed according to the weak brace – strong gusset concept, were tested. The objective was to investigate the effects of displacement history, brace effective slenderness ratio, and brace width/thickness ratio, on the hysteresis behaviour of bracing members. Displacement history was found to affect energy dissipation and fracture life. The effects of increasing the gusset plate thickness on the energy dissipation and the fracture life is not the same as reducing the effective slenderness ratio of the bracing member resulted from reducing the length of the HSS. New fracture life and energy life equations are proposed.
Carbon utilization profiles of Fusarium virguliforme isolates
Authors: Tang E. , Hill C.B. , Hartman G.L.
Published: December 2010

Fusarium virguliforme is the cause of sudden death syndrome in soybean. Physiological variability among isolates of the fungus is unknown. One way to measure physiologic variability is to analyze growth on different carbon sources. The carbon source utilization profiles of 18 F. virguliforme isolates were examined using the Biolog FF 96-well microplate, which contains 95 different carbon sources. The utilization of dextrin, d-mannitol, maltotriose, d-lactic acid methyl ester, N-acetyl-d-galactosamine, salicin, d-trehalose, and l-alanine differed significantly among isolates (P = 0.05). Carbon sources were grouped into 3 clusters based on their ability to promote growth of F. virguliforme, after calculating Euclidean distances among them. About 12% of the carbon sources promoted a high amount of mycelial growth, 39% promoted a medium amount of growth, and 49% promoted a low amount of mycelial growth; the latter was not significantly different from the water blank control. A hierarchical tree diagram was produced for the 18 isolates based on their carbon source utilization profiles using Ward’s hierarchical analysis method. Two main clusters of isolates were formed. One cluster represented greater average mycelial growth on all of the carbon sources than the other cluster. In this study, variability in carbon source utilization among F. virguliforme isolates was evident, but the results were not associated with geographic origin of the isolates, year collected, or published data on aggressiveness. Additional research is needed to determine if these carbon utilization profiles are associated with other biological characteristics, like spore germination, propagule formation, and saprophytic competitiveness.
Passive protection of purified yolk immunoglobulin administered against Shiga toxin 1 in mouse models
Authors: Wang Qin , Hou Xiao-jun , Cai Kun , Li Tao , Liu Yue-nan , Tu Wei , Xiao Le , Bao Shi-zhong , Shi Jing , Gao Xiang , Liu Hao , Tian Ren-mao , Wang Hui
Published: December 2010

Shiga toxins produced by Escherichia coli O157:H7 cause a wide spectrum of enteric diseases, such as lethal hemorrhagic colitis and hemolytic uremic syndrome. In this study, the B subunit protein of Shiga toxin type 1 (Stx1) was produced in the E. coli system, was further purified by Ni-column Affinity Chromatography method, and was then used as an immunogen to immunize laying hens for yolk immunoglobulin (IgY) production. Titers of IgY increased gradually with boosting vaccination and, finally, reached a level of 105, remaining steady over 1 year. Then the protective efficacy of IgY against Stx1 was evaluated by in vitro and in vivo experiments. It was shown that the anti-Stx1 IgY could effectively block the binding of Stx1 to the Hela cells and could protect BALB/c mice from toxin challenges. The data indicates the facility of using egg yolk IgY as a therapeutic intervention in cases of Shiga toxin intoxication.
Effect of phosphatidylcholine–cholesterol liposomes on Entamoeba histolytica virulence
Authors: Serrano-Luna Jesús , Gutiérrez-Meza Manuel , Mejía-Zepeda Ricardo , Galindo-Gómez Silvia , Tsutsumi Víctor , Shibayama Mineko
Published: December 2010

Trophozoites of Entamoeba histolytica HM-1:IMSS become less virulent after long-term maintenance in axenic cultures. The factors responsible for the loss of virulence during in vitro cultivation remain unclear. However, it is known that in vitro cultivation of amoeba in culture medium supplemented with cholesterol restores their virulence. In this study, we analyzed the effect of adding phosphatidylcholine–cholesterol (PC–Chol) liposomes to the culture medium and evaluated the effect of this lipid on various biochemical and biological functions of E. histolytica HM-1:IMSS in terms of its virulence. The addition of PC–Chol liposomes to the culture medium maintained the virulence of these parasites against hamster liver at the same level as the original virulent E. histolytica strain, even though these amoebae were maintained without passage through hamster liver for 18 months. The trophozoites also showed increased endocytosis, erythrophagocytosis, and carbohydrate residue expression on the amoebic surface. Protease activities were also modified by the presence of cholesterol in the culture medium. These findings indicate the capacity of cholesterol to preserve amoeba virulence and provide an alternative method for the maintenance of virulent E. histolytica trophozoites without the need for in vivo procedures.
Shikonin inhibits the proliferation and induces the apoptosis of human HepG2 cells
Authors: Yingkun Nie , Lvsong Zhu , Huimin Yu
Published: December 2010

This study investigated the potential of shikonin as an anticancer agent against liver cancer and an in vitro human hepatoma cancer model system. The HepG2 cell line was the hepatoma cancer model in the present study. The inhibitory effect of shikonin on the growth of HepG2 cells was measured by MTT assay. To explore the underlying mechanism of cell growth inhibition of shikonin, the cell cycle distribution, DNA fragmentation, mitochondrial membrane potential (Δ[Formula: see text]m) disruption, and expression of Bax and Bcl-2 were measured in HepG2 cells. The activity of shikonin in inducing apoptosis was investigated through the detection of Annexin V signal and CD95 expression by flow cytometry and electron microscopy, respectively. Shikonin inhibited the growth of HepG2 cells in a dose-dependent manner. The IC50 value (inhibiting cell growth by 50%) was 4.30 µg/mL. Shikonin inhibited cell growth in a dose-dependent manner and blocked HepG2 cell cycle progression at the S phase. The changes in mitochondrial morphology, dose-dependently decreased in Δ[Formula: see text]m, were observed in different concentrations of the drug treatment group. Western blot analysis showed that cajanol inhibited Bcl-2 expression and induced Bax expression. Furthermore, we show that shikonin increases Annexin V signal and CD95 (Fas/APO) expression, resulting in apoptotic cell death of HepG2 cells. In addition, lump formation of intranuclear chromatin, pyknosis of cell nucleus, deletion of microvillus, vacuolar degeneration of mitochondria, reduction of rough endoplasmic reticulum, and resolution of free ribosome, etc., associated with apoptosis were discovered by electron microscopy in HepG2 cells after 48 h treatment. Shikonin inhibited HepG2 cells, possibly through the pathway of inducing early apoptosis, and was beneficial for restoring the apoptotic sensitivity of HepG2 cells by CD95, and should therefore be considered as a candidate agent for the prevention or treatment of human hepatoma.
Correlations between aortic stiffness and parasympathetic autonomic function in healthy volunteers
Authors: Nemes Attila , Takács Róbert , Gavallér Henriette , Várkonyi Tamás T. , Wittmann Tibor , Forster Tamás , Lengyel Csaba
Published: December 2010

Cardiovascular autonomic dysfunction and alterations in vascular elasticity are known complications of several disorders, including diabetes mellitus, hypertension, hypercholesterolemia, aging, and chronic kidney disease. The current study was designed to test whether a relationship existed between pulse wave velocity (PWV), augmentation index (AIx), aortic elastic properties, and cardiovascular autonomic function in healthy volunteers. The study comprised 25 healthy volunteers, whose aortic strain, distensibility, and stiffness index were measured by echocardiography, whereas PWV and AIx were evaluated by Arteriograph (TensioMed, Budapest, Hungary) in all cases. Autonomic function was assessed by means of 5 standard cardiovascular reflex tests. We found that heart rate response to deep breathing, as the most reproducible cardiovascular reflex test to characterize parasympathetic function, showed low to moderate correlations with PWV (r = –0.431, p = 0.032), aortic strain (r = 0.594, p = 0.002), distensibility (r = 0.407, p = 0.043), and stiffness index (r = –0.453, p = 0.023). Valsalva ratio and autonomic neuropathy score (ANS) correlated with PWV (r = –0.557, p = 0.004 and r = –0.421, p = 0.036, respectively) and AIx (r = –0.461, p = 0.020 and r = –0.385, p = 0.057, respectively), while ANS correlated with even aortic stiffness index (r = –0.457, p = 0.022). Cardiovascular reflex tests mainly characterizing sympathetic function had no correlation with aortic stiffness parameters (p = NS for all correlations). Correlations exist between parameters characterizing aortic elasticity and parasympathetic autonomic function, as shown by standard cardiovascular reflex tests in healthy volunteers.
Cooperative mechanisms of acute antidiuretic response to bendroflumethiazide in rats with lithium-induced nephrogenic diabetes insipidus
Authors: Moosavi S. Mostafa Shid , Haghani Masoud
Published: December 2010

The exact mechanism underlying thiazides-induced paradoxical antidiuresis in diabetes insipidus is still elusive, but it has been hypothesized that it is exerted either via Na+-depletion activating volume-homeostatic reflexes to decrease distal delivery, or direct stimulation of distal water reabsorption. This study examined how these two proposed mechanisms actually cooperate to induce an acute bendroflumethiazide (BFTZ)-antidiuretic effect in nephrogenic diabetes insipidus (NDI). Anaesthetized rats with lithium (Li)-induced NDI were prepared in order to measure their renal functional parameters, and in some of them, bilateral renal denervation (DNX) was induced. After a 30 min control clearance period, we infused either BFTZ into 2 groups, NDI+BFTZ and NDI/DNX+BFTZ, or its vehicle into a NDI+V group, and six 30 min experimental clearance periods were taken. During BFTZ infusion in the NDI+BFTZ group, transiently elevated Na+excretion was associated with rapidly increased urinary osmolality and decreased free water clearance, but Li clearance and urine flow declined in the later periods. However, in the NDI/DNX+BFTZ group, there was persistently elevated Na+excretion with unchanged Li clearance and urine flow during the experimental period, while alterations in free water clearance and urinary osmolality resembled those in the NDI+BFTZ group. In conclusion, BFTZ initially exerted two direct effects of natriuresis–diuresis and stimulating free water reabsorption at the distal nephron in NDI, which together elevated Na+excretion and urinary osmolality but kept the urine volume unchanged in the first hour. Thereafter, the resultant sodium depletion led to the activation of neural reflexes that reduced distal fluid delivery to compensate for BFTZ-induced natriuresis–diuresis which, in cooperation with the direct distal BFTZ-antidiuretic effect, resulted in excretion of urine with a low volume, high osmolality, and normal sodium.
Autophagy, apoptosis, and ecdysis-related gene expression in the silk gland of the silkworm (Bombyx mori) during metamorphosis
Authors: Li Qingrong , Deng Xiaojuan , Yang Wanying , Huang Zhijun , Tettamanti Gianluca , Cao Yang , Feng Qili
Published: December 2010

Degeneration of larval-specific tissues during insect metamorphosis has been suggested to be the result of apoptosis and autophagy and is triggered by ecdysteroids. However, the relationship between autophagy and apoptosis pathways and the mechanism of regulation by ecdysteroids remain to be elucidated. This study examined the events of autophagy, apoptosis, and the expression of ecdysis-related genes in the silk gland of the silkworm ( Bombyx mori L., 1758) during the larval to pupal transformation. The results indicated that autophagic features appeared in the silk gland at the wandering and spinning stages of the larvae, whereas the apoptotic features such as apoptotic bodies and DNA fragmentation occurred at the prepupal or early-pupal stages. The autophagic granules fused with each other to form large vacuoles where the cytoplasmic material was degraded. Autophagosomes, autolysosomes, and apoptotic bodies were found later in the degenerating silk-gland cells. Expression of the ecdysone receptor gene BmEcR and the transcription factor genes BmE74A and BmBR-C preceded the onset of autophagy and apoptosis, indicating that they may be responsible for triggering these programmed cell death pathways in the silk gland. The results suggest that both autophagy and apoptosis occur in the silk-gland cells during degeneration, but autophagy precedes apoptosis.
SHORTEST PATH SIMPLEX ALGORITHM WITH A MULTIPLE PIVOT RULE: A COMPARATIVE STUDY
Authors: SEDEÑO-NODA A. , GONZÁLEZ-MARTÍN C.
Published: December 2010

This paper introduces a new multiple pivot shortest path simplex method by choosing a subset of non-basic arcs to simultaneously enter into the basis. It is shown that the proposed shortest path simplex method requires O (n) multiple pivots and its running time is O (nm). Results from a computational study comparing the proposed method from previously known methods are reported. The experimental show that the proposed rule is more efficient than the considered shortest path simplex pivot rules.
Synthesis, electrochemistry and spectroelectrochemistry of tetraundecylporphyrins in nonaqueous media
Authors: Kadish Karl M. , Ou Zhongping , Zhan Riqiang , Khoury Tony , E Wenbo , Crossley Maxwell J.
Published: December 2010

Six meso-substituted tetraundecylporphyrins were prepared in high yield using an improved synthetic method and then characterized by electrochemistry and spectroelectrochemistry as well as UV-vis, FTIR and NMR spectroscopy. The examined compounds are represented as (TUP)M where M = H2, ZnII, CuII, NiII, PdII or MnIIICl and TUP is the dianion of a porphyrin having undecyl groups (-CH2(CH2)9CH3) on the four meso-positions of the macrocycle. Two oxidations are observed for each compound in CH2Cl2 and PhCN containing 0.1 M TBAP, leading to the stepwise formation of π-cation radicals and dications. The free-base and MnIIICl derivatives undergo two reductions but only one reversible reduction is seen for the other porphyrins under the given solution conditions. Comparisons are made between the electrochemical behavior of the (TUP)M derivatives and two related series of porphyrins, (TPP)M and (OEP)M. The effect of substituents on the meso-positions of the TUP macrocycle is also discussed.
Microwave assisted solid-phase synthesis of substituted tetraazaporphyrins and a phthalocyanine-peptide conjugate
Authors: Mudyiwa Mercy , Ndinguri Margaret W. , Soper Steven A. , Hammer Robert P.
Published: December 2010

Various asymmetrically substituted phthalocyanines (Pcs) and porphyrazines (Pzs) have been synthesized in good yields using a solid-phase synthesis method with a poly(ethylene glycol) (PEG) resin attached to an indole linker as the solid support. These compounds are formed by cross condensation of maleonitrile or phthalonitrile with another phthalonitrile covalently bonded to the solid support with an amino linking group. The polymer bound Pc or Pz is separated by filtration, and washing the symmetrical Pc or Pz by-product. The amine Pc -appended to polyethylene glycol resin is further reacted to yield azide whilst still on the solid support. Cleavage of the Pc or Pz off the solid support results in 3:1 asymmetric Pz or Pz with high degree of purity, requiring minimal further purification. The use of hydrophilic PEG-based resin allows the symmetrical compound to be removed completely by washing whereas the acid labile indole linker makes it easier to cleave the product under mild conditions. The conjugation abilities of these compounds have been demonstrated by the successful conjugation of one of the azide Pcs with a peptide elaborated with an alkyne function. Use of microwave for the synthesis of these compounds results in shorter reaction times, higher yields and higher degree of purity.
Synthesis, characterization and catalytic oxidation performance of new planar binuclear phthalocyanines sharing the benzene ring
Authors: Lu Guiguang , Zhou Yulu , Xiang Yuzhi , Xia Daohong
Published: December 2010

The crude product of hexacarboxy biphtalocyanines cobalt ( CoBPcC6 ) was synthesized by fusing trimellitic anhydride, pyromellitic dianhydride, urea and CoCl2 · 6H2O with ammonium molybdate as catalyst and then hydrolyzed under alkaline conditions. The crude product was isolated by acidifying with hydrochloric acid followed by filtration, then purified by reprecipitation from concentrated sulfuric acid followed by chromatography on silica gel column. CoBPcC6 was characterized by IR, UV-vis, 1 H NMR, elemental analysis, etc. The activity of CoBPcC6 catalyst for extractive sweetening was evaluated by studying mercaptide oxidation. It was found that the performance of this immobilized catalyst was better than the commercial immobilized catalyst.
On Classical and Quantum Liftings
Authors: Accardi L. , Chruściński D. , Kossakowski A. , Matsuoka T. , Ohya M.
Published: December 2010

We analyze the procedure of lifting in classical stochastic and quantum systems. It enables one to 'lift' a state of a system into a state of 'system + reservoir'. This procedure is important both in quantum information theory and the theory of open systems. We illustrate the general theory of liftings by a particular class related to so-called circulant states.
Stochastic Master Equations in Thermal Environment
Authors: Attal Stéphane , Pellegrini Clément
Published: December 2010

We derive stochastic master equations which describe the evolution of open quantum systems in contact with a heat bath and undergoing indirect measurements. These equations are obtained as a limit of a quantum repeated measurement model where we consider a small system in contact with an infinite chain at positive temperature. It is well-known that at zero temperature one obtains stochastic differential equations of jump-diffusion type. We show that only pure diffusion type equations are relevant at strictly positive temperatures.
Reflections on the Toyota debacle
Authors: Cusumano Michael A.
Published: December 2010

A look in the rearview mirror reveals system and process blind spots.
Collaboration in system administration
Authors: Haber Eben M. , Kandogan Eser , Maglio Paul P.
Published: December 2010

For sysadmins, solving problems usually involves collaborating with others. How can we make it more effective?
A firm foundation for private data analysis
Authors: Dwork Cynthia
Published: December 2010

What does it mean to preserve privacy?
Modeling Social Annotation
Authors: Plangprasopchok Anon , Lerman Kristina
Published: December 2010

Collaborative tagging systems, such asDelicious, CiteULike, and others, allow users to annotate resources, for example, Web pages or scientific papers, with descriptive labels calledtags. The social annotations contributed by thousands of users can potentially be used to infer categorical knowledge, classify documents, or recommend new relevant information. Traditional text inference methods do not make the best use of social annotation, since they do not take into account variations in individual users’ perspectives and vocabulary. In a previous work, we introduced a simple probabilistic model that takes the interests of individual annotators into account in order to find hidden topics of annotated resources. Unfortunately, that approach had one major shortcoming: the number of topics and interests must be specified a priori. To address this drawback, we extend the model to a fully Bayesian framework, which offers a way to automatically estimate these numbers. In particular, the model allows the number of interests and topics to change as suggested by the structure of the data. We evaluate the proposed model in detail on the synthetic and real-world data by comparing its performance to Latent Dirichlet Allocation on the topic extraction task. For the latter evaluation, we apply the model to infer topics of Web resources from social annotations obtained fromDeliciousin order to discover new resources similar to a specified one. Our empirical results demonstrate that the proposed model is a promising method for exploiting social knowledge contained in user-generated annotations.
Fast Discovery of Group Lag Correlations in Streams
Authors: Sakurai Yasushi , Faloutsos Christos , Papadimitriou Spiros
Published: December 2010

The study of data streams has received considerable attention in various communities (theory, databases, data mining, networking), due to several important applications, such as network analysis, sensor monitoring, financial data analysis, and moving object tracking. Our goal in this article is to monitor multiple numerical streams and determine which pairs are correlated with lags, as well as the value of each such lag. Lag correlations and anticorrelations are frequent and very interesting in practice. For example, a decrease in interest rates typically precedes an increase in house sales by a few months; higher amounts of fluoride in drinking water may lead to fewer dental cavities some years later. Other lag settings include network analysis, sensor monitoring, financial data analysis, and tracking of moving objects. Such data streams are often correlated or anticorrelated, but with unknown lag.

We propose BRAID, a method of detecting lag correlations among data streams. BRAID can handle data streams of semi-infinite length incrementally, quickly, and with small resource consumption. However, BRAID requires space and time quadratic on a number of streams
k
. We also propose ThinBRAID, which is even faster than BRAID, requiring
O
(
k
) space and time per time tick. Our theoretical analysis shows that BRAID/ThinBRAID can estimate lag correlations with little or, often, with
no
error. Our experiments on real and realistic data show that BRAID and ThinBRAID detect the correct lag perfectly most of the time (the largest relative error was about 1%), while they are significantly faster (up to 40,000 times) than the naïve implementation.
Epistemic privacy
Authors: Evfimievski Alexandre , Fagin Ronald , Woodruff David
Published: December 2010

We present a novel definition of privacy in the framework of offline (retroactive) database query auditing. Given information about the database, a description of sensitive data, and assumptions about users' prior knowledge, our goal is to determine if answering a past user's query could have led to a privacy breach. According to our definition, an audited propertyAis private, given the disclosure of propertyB, if no user can gain confidence inAby learningB, subject to prior knowledge constraints. Privacy is not violated if the disclosure ofBcauses a loss of confidence inA. The new notion of privacy is formalized using the well-known semantics for reasoning about knowledge, where logical properties correspond to sets of possible worlds (databases) that satisfy these properties. Database users are modeled as either possibilistic agents whose knowledge is a set of possible worlds, or as probabilistic agents whose knowledge is a probability distribution on possible worlds.

We analyze the new privacy notion, show its relationship with the conventional approach, and derive criteria that allow the auditor to test privacy efficiently in some important cases. In particular, we prove characterization theorems for the possibilistic case, and study in depth the probabilistic case under the assumption that all database records are considered a-priori independent by the user, as well as under more relaxed (or absent) prior-knowledge assumptions. In the probabilistic case we show that for certain families of distributions there is no efficient algorithm to test whether an audited propertyAis private given the disclosure of a propertyB, assumingP≠NP. Nevertheless, for many interesting families, such as the family of product distributions, we obtain algorithms that are efficient both in theory and in practice.
Gated-diode FinFET DRAMs
Authors: Bhoj Ajay N. , Jha Niraj K.
Published: December 2010

Scaling bulk CMOS SRAM technology for on-chip caches beyond the 22nm node is questionable, on account of high leakage power consumption, performance degradation, and instability due to process variations. Recently, two-three transistor one gated-diode (2T/3T1D) DRAMs were proposed as alternatives to address the SRAM variability problem, with an emphasis on high-activity embedded cache applications. They are highly competitive to SRAM in terms of performance, while having a smaller power and area footprint at lower technology nodes. The current evolutionary trend in transistor structures is moving toward an era of multigate devices, which makes it necessary to identify design issues and advantages of gated-diode DRAMs implemented in a multigate technology.

In this work, we address gated-diode DRAM design in FinFET technology using mixed-mode 2D-device simulations. We revisit the model of internal voltage gain in bulk gated diodes and extend it to provide quantitative insight into designing Fin gated diodes, that is, gated diodes in FinFET technology. To this effect, we propose FinFET variants of the bulk gated-diode configuration and identify parameters that are critical to enhancing the retention time and read current in 2T/3T1D FinFET DRAMs. Additionally, we show the superiority of 2T1D FinFET DRAM over 6T FinFET SRAM having pass-gate feedback (6T PGFB) and 2T1D bulk DRAM under the effect of physical parameter process variations using a quasi--Monte Carlo method implemented in FinE, an environment we have developed for double-gate circuit design that integrates Sentaurus TCAD from Synopsys with the Spice3-UFDG double-gate compact model from University of Florida, under a single framework. Finally, we present a new tunable threshold gated diode FinFET amplifier which uses an n-type gated diode for voltage-boosting, along with a p-type gated diode for zero-suppression.
Glucagon-like peptide-2-stimulated protein synthesis through the PI 3-kinase-dependent Akt-mTOR signaling pathway
Authors: Shi Xuemei , Li Xiaojie , Wang Yi , Zhang Keying , Zhou Fuguo , Chan Lawrence , Li Defa , Guan Xinfu
Published: December 2010

Glucagon-like peptide-2 (GLP-2) is a nutrient-responsive neuropeptide that exerts diverse actions in the gastrointestinal tract, including enhancing mucosal cell survival and proliferation. GLP-2 stimulates mucosal growth in vivo with an increased rate of protein synthesis. However, it was unclear whether GLP-2 can directly stimulate protein synthesis. The objective was to test critically whether GLP-2 receptor (GLP-2R) activation directly stimulates protein synthesis through a PI 3-kinase-dependent Akt-mTOR signaling pathway. HEK 293 cells (transfected with human GLP-2R cDNA) were treated with human GLP-2 with/without pretreatment of PI 3-kinase inhibitor (LY-294002) or mTOR inhibitor (rapamycin). Results show that 1) GLP-2 specifically bound to GLP-2R overexpressed in the HEK cells with Ka = 0.22 nM and Bmax = 321 fmol/μg protein; 2) GLP-2-stimulated protein synthesis was dependent on the amount of GLP-2R cDNA and the dosage of GLP-2 and reached the plateau among 0.2–2 nM GLP-2; 3) GLP-2-stimulated protein synthesis was abolished by the PI 3-kinase inhibitor and mTOR inhibitor; and 4) GLP-2-mediated stimulation of phosphorylation on Akt and mTOR was dependent on the amount of GLP-2R cDNA transfected and the dosage of GLP-2. In addition, GLP-2-mediated action and signaling in regulation of protein synthesis were confirmed in mouse hippocampal neurons (expressing native GLP-2R). GLP-2 directly stimulated protein synthesis of primary cultured neurons in dosage-dependent, PI 3-kinase-dependent, and rapamycin-sensitive manners, which linked with activation of Akt-mTOR signaling pathway as well. We conclude that GLP-2R activation directly stimulates protein synthesis by activating the PI 3-kinase-dependent Akt-mTOR signaling pathway. GLP-2-stimulated protein synthesis may be physiologically relevant to maintaining neuronal long-term potentiation and providing secondary mediators (namely neuropeptides or growth factors).
Chronic estradiol exposure induces oxidative stress in the hypothalamus to decrease hypothalamic dopamine and cause hyperprolactinemia
Authors: MohanKumar Sheba M. J. , Kasturi Badrinarayanan S. , Shin Andrew C. , Balasubramanian Priya , Gilbreath Ebony T. , Subramanian Madhan , MohanKumar Puliyur S.
Published: December 2010

Estrogens are known to cause hyperprolactinemia, most probably by acting on the tuberoinfundibular dopaminergic (TIDA) system of the hypothalamus. Dopamine (DA) produced by TIDA neurons directly inhibits prolactin secretion and, therefore, to stimulate prolactin secretion, estrogens inhibit TIDA neurons to decrease DA production. However, the mechanism by which estrogen produces this effect is not clear. In the present study, we used a paradigm involving chronic exposure to low levels of estradiol-17β (E2) to mimic prolonged exposures to environmental and endogenous estrogens. We hypothesized that chronic exposure to low levels of E2 induces oxidative stress in the arcuate nucleus (AN) of the hypothalamus that contains TIDA neurons and causes nitration of tyrosine hydroxylase (TH), the rate-limiting enzyme in the synthesis of DA. This results in a significant decrease in DA and consequently, hyperprolactinemia. To investigate this, adult, intact female cycling rats were implanted with slow-release E2 pellets (20 ng/day) for 30, 60, or 90 days and were compared with old (16–18 mo old) constant estrous (OCE) rats. Chronic E2 exposure significantly increased the expression of glial fibrillary acidic protein and the concentrations of interleukin-1β (IL-1β) and nitrate in the AN that contains perikarya of TIDA neurons and increased nitration of TH in the median eminence (ME) that contains the terminals. These levels were comparable to those seen in OCE rats. We observed a significant decrease in DA concentrations in the ME and hyperprolactinemia in an exposure-dependent manner similar to that seen in OCE rats. It was concluded that chronic exposure to low levels of E2 evokes oxidative stress in the AN to inhibit TIDA neuronal function, most probably leading to hyperprolactinemia.
Spatial summation in macaque parietal area 7a follows a winner-take-all rule
Authors: Oleksiak Anna , Klink P. Christiaan , Postma Albert , van der Ham Ineke J. M. , Lankheet Martin J. , van Wezel Richard J. A.
Published: December 2010

While neurons in posterior parietal cortex have been found to signal the presence of a salient stimulus among multiple items in a display, spatial summation within their receptive field in the absence of an attentional bias has never been investigated. This information, however, is indispensable when one investigates the mechanisms of spatial attention and competition between multiple visual objects. To examine the spatial summation rule in parietal area 7a neurons, we trained rhesus monkeys to fixate on a central cross while two identical stimuli were briefly displayed in a neuron's receptive field. The response to a pair of dots was compared with the responses to the same dots when they were presented individually. The scaling and power parameters of a generalized summation algorithm varied greatly, both across neurons and across combinations of stimulus locations. However, the averaged response of the recorded population of 7a neurons was consistent with a winner-take-all rule for spatial summation. A control experiment where a monkey covertly attended to both stimuli simultaneously suggests that attention introduces additional competition by facilitating the less optimal stimulus. Thus an averaging stage is introduced between ∼200 and 300 ms of the response to a pair of stimuli. In short, the summation algorithm over the population of area 7a neurons carries the signature of a winner-take-all operation, with spatial attention possibly influencing the temporal dynamics of stimulus competition, that is the moment that the “winner” takes “victory” over the “loser” stimulus.
Selective gene expression by rat gastric corpus epithelium
Authors: Goebel M. , Stengel A. , Lambrecht N. W. G. , Sachs G.
Published: December 2010

The gastrointestinal (GI) tract is divided into several segments that have distinct functional properties, largely absorptive. The gastric corpus is the only segment thought of as largely secretory. Microarray hybridization of the gastric corpus mucosal epithelial cells was used to compare gene expression with other segments of the columnar GI tract followed by statistical data subtraction to identify genes selectively expressed by the rat gastric corpus mucosa. This provides a means of identifying less obvious specific functions of the corpus in addition to its secretion-related genes. For example, important properties found by this GI tract comparative transcriptome reflect the energy demand of acid secretion, a role in lipid metabolism, the large variety of resident neuroendocrine cells, responses to damaging agents and transcription factors defining differentiation of its epithelium. In terms of overlap of gastric corpus genes with the rest of the GI tract, the distal small bowel appears to express many of the gastric corpus genes in contrast to proximal small and large bowel. This differential map of gene expression by the gastric corpus epithelium will allow a more detailed description of major properties of the gastric corpus and may lead to the discovery of gastric corpus cell differentiation genes and those mis-regulated in gastric carcinomas.
Role of Nutrition in the Management of Hepatic Encephalopathy in End-Stage Liver Failure
Authors: Bémeur Chantal , Desjardins Paul , Butterworth Roger F.
Published: December 2010

Malnutrition is common in patients with end-stage liver failure and hepatic encephalopathy, and is considered a significant prognostic factor affecting quality of life, outcome, and survival. The liver plays a crucial role in the regulation of nutrition by trafficking the metabolism of nutrients, their distribution and appropriate use by the body. Nutritional consequences with the potential to cause nervous system dysfunction occur in liver failure, and many factors contribute to malnutrition in hepatic failure. Among them are inadequate dietary intake, malabsorption, increased protein losses, hypermetabolism, insulin resistance, gastrointestinal bleeding, ascites, inflammation/infection, and hyponatremia. Patients at risk of malnutrition are relatively difficult to identify since liver disease may interfere with biomarkers of malnutrition. The supplementation of the diet with amino acids, antioxidants, vitamins as well as probiotics in addition to meeting energy and protein requirements may improve nutritional status, liver function, and hepatic encephalopathy in patients with end-stage liver failure.
Comparative Quality of Laparoscopic and Open Cholecystectomy in the Elderly Using Propensity Score Matching Analysis
Authors: Kuwabara Kazuaki , Matsuda Shinya , Ishikawa Koichi Benjamin , Horiguchi Hiromasa , Fujimori Kenji
Published: December 2010

The safety of laparoscopic cholecystectomy (LC) in patients ≥65 years of age requires further investigation of postoperative outcomes before it becomes more widely accepted as a safe technique. The advantages of using LC versus open cholecystectomy (OC) in elderly patients were analyzed using propensity score matching. The demographics, cholecystitis severity, comorbidities, complications, and admission and discharge Barthel Index (BI) scores of patients with benign gallbladder diseases were analyzed. Outcomes were analyzed by age, length of stay (LOS), total charges (TCs), BI improvement, and postoperative complications. OC, which was indicated in severe disease cases, increased hospital resource use and caused more complications than LC, but did not improve BI. Advanced age and OC resulted in greater LOS and TCs and was the best indicator of BI deterioration. Whenever possible, surgeons should use LC in elderly patients to minimize postoperative complications and allow them to regain a good quality of life.
Connectivity-Guaranteed Hybrid Topology Management Scheme for Improving the Operational Lifetime of 3-Dimensional Wireless Sensor Networks
Authors: Jawahar A. , Radha S. , Vadivelan S.
Published: December 2010

The battery of limited energy operates wireless sensor nodes, it is important to increase the lifetime of the wireless sensor network. The aim of our work is to design a hybrid topology management scheme for improving the lifetime of the wireless sensor networks with guaranteed connectivity. The sensing range of the sensor node is smaller than the radio range and hence there is a large number of nodes within the coverage area of a node. Hence the network connectivity can be maintained with less number of nodes. By using this fact, we can save energy by switching off the transceiver, which consumes most of the energy. On the other hand, the sensor node spends most of the time in monitoring state and the transceiver is idle. In the idle state the transceiver consumes almost the same energy as in receiving state. Hence putting the transceiver in the sleep mode when it is idle can save the significant energy. We have designed a hybrid topology management scheme for 3-Dimensional sensor networks by making use of these facts. Our hybrid scheme improves the lifetime of the 3-Dimensional sensor network by a factor of 19.
Beyond Histone and Deacetylase: An Overview of Cytoplasmic Histone Deacetylases and Their Nonhistone Substrates
Authors: Yao Ya-Li , Yang Wen-Ming
Published: December 2010

Acetylation of lysines is a prominent form of modification in mammalian proteins. Deacetylation of proteins is catalyzed by histone deacetylases, traditionally named after their role in histone deacetylation, transcriptional modulation, and epigenetic regulation. Despite the link between histone deacetylases and chromatin structure, some of the histone deacetylases reside in various compartments in the cytoplasm. Here, we review how these cytoplasmic histone deacetylases are regulated, the identification of nonhistone substrates, and the functional implications of their nondeacetylase enzymatic activities.
The Effects of Very-Low-Calorie Diets on HDL: A Review
Authors: Rolland Catherine , Broom Iain
Published: December 2010

This paper investigates the effects of very-low-calorie diets (VLCDs) used in the treatment of obesity on high-density lipoprotein (HDL) levels. Although the studies varied widely in their intervention format, duration, and baseline HDL levels, it would appear that HDL levels usually decrease during active weight loss using a VLCD, but these either return to pre-VLCD levels or improve overall during the weight-maintenance phase. More research needs to be done to determine optimal weight-maintenance programmes and the effects of VLCDs in the short term as well as on HDL levels in groups at increased risk of coronary heart disease.
The Role of Chemokine Receptor CXCR4 in the Biologic Behavior of Human Soft Tissue Sarcoma
Authors: Kim Roger H. , Li Benjamin D. L. , Chu Quyen D.
Published: December 2010

The molecular basis of sarcoma remains poorly understood. However, recent studies have begun to uncover some of the molecular pathways involved in sarcomagenesis. The chemokine receptor CXCR4 has been implicated in sarcoma development and has been found to be a prognostic marker for poor clinical outcome. There is growing evidence that overexpression of CXCR4 plays a significant role in development of metastatic disease, especially in directing tumor cells towards the preferential sites of metastases in sarcoma, lung and bone. Although further investigation is necessary to validate these pathways, there is potential for clinical application, particularly in the use of pharmacologic inhibitors of CXCR4 as means of preventing sarcoma metastasis.
Diagnosis and Prognostication of Ductal Adenocarcinomas of the Pancreas Based on Genome‐Wide DNA Methylation Profiling by Bacterial Artificial Chromosome Array‐Based Methylated CpG Island Amplification
Authors: Gotoh Masahiro , Arai Eri , Wakai-Ushijima Saori , Hiraoka Nobuyoshi , Kosuge Tomoo , Hosoda Fumie , Shibata Tatsuhiro , Kondo Tadashi , Yokoi Sana , Imoto Issei , Inazawa Johji , Kanai Yae
Published: December 2010

To establish diagnostic criteria for ductal adenocarcinomas of the pancreas (PCs), bacterial artificial chromosome (BAC) array‐based methylated CpG island amplification was performed using 139 tissue samples. Twelve BAC clones, for which DNA methylation status was able to discriminate cancerous tissue (T) from noncancerous pancreatic tissue in the learning cohort with a specificity of 100%, were identified. Using criteria that combined the 12 BAC clones, T‐samples were diagnosed as cancers with 100% sensitivity and specificity in both the learning and validation cohorts. DNA methylation status on 11 of the BAC clones, which was able to discriminate patients showing early relapse from those with no relapse in the learning cohort with 100% specificity, was correlated with the recurrence‐free and overall survival rates in the validation cohort and was an independent prognostic factor by multivariate analysis. Genome‐wide DNA methylation profiling may provide optimal diagnostic markers and prognostic indicators for patients with PCs.
Impairment of Methotrexate Transport Is Common in Osteosarcoma Tumor Samples
Authors: Sowers Rebecca , Wenzel Bethanne D. , Richardson Condon , Meyers Paul A. , Healey John H. , Levy Adam S. , Gorlick Richard
Published: December 2010

Osteosarcoma does not respond well to conventional dose methotrexate but does respond to high-dose methotrexate. Previous work has indicated that this resistance may be due to impaired transport of methotrexate across the cell membrane. In this study, the PT430 competitive displacement assay was adapted to evaluate methotrexate transport in 69 high-grade osteosarcoma tumor samples. All samples studied were shown to have relatively impaired methotrexate transport by PT430 assay. Ninety-nine percent of the samples had less than 20% PT430 displacement by methotrexate. Eighty-eight percent exhibited displacement by methotrexate at less than 50% of the displacement by trimetrexate. The high frequency of impaired transport suggests the presence of decreased functionality of the reduced folate carrier protein. The overwhelming presence of impaired transport may explain why methotrexate needs to be given in high doses to be effective in osteosarcoma therapy and suggests that reduced folate carrier-independent antifolates should be explored.