bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of allelic differential expression in the human genome using allele-specific serial analysis of gene expression tags
Authors: Vidal Daniel Onofre , de Souza Jorge Estefano S. , Pires Lilian Campos , Masotti Cibele , Salim Anna Christina Matos , Costa Maria Cristina Ferreira , Galante Pedro Alexandre Favoretto , de Souza Sandro José , Camargo Anamaria Aranha
Published: February 2011

Recent reports have demonstrated that a significant proportion of human genes display allelic differential expression (ADE). ADE is associated with phenotypic variability and may contribute to complex genetic diseases. Here, we present a computational analysis of ADE using allele-specific serial analysis of gene expression (SAGE) tags representing 1295 human genes. We identified 472 genes for which unequal representation (>3-fold) of allele-specific SAGE tags was observed in at least one SAGE library, suggesting the occurrence of ADE. For 235 out of these 472 genes, the difference in the expression level between both allele-specific SAGE tags was statistically significant (p < 0.05). Eleven candidate genes were then subjected to experimental validation and ADE was confirmed for 8 out of these 11 genes. Our results suggest that at least 25% of the human genes display ADE and that allele-specific SAGE tags can be efficiently used for the identification of such genes.
In silico identification and characterization of microRNAs and their putative target genes in Solanaceae plants
Authors: Kim Hyun-Jin , Baek Kwang-Hyun , Lee Bong-Woo , Choi Doil , Hur Cheol-Goo
Published: February 2011

MicroRNAs (miRNAs) are a class of small, single-stranded, noncoding RNAs ranging from 19 to 25 nucleotides. The miRNA control various cellular functions by negatively regulating gene expression at the post-transcriptional level. The miRNA regulation over their target genes has a central role in regulating plant growth and development; however, only a few reports have been published on the function of miRNAs in the family Solanaceae. We identified Solanaceae miRNAs and their target genes by analyzing expressed sequence tag (EST) data from five different Solanaceae species. A comprehensive bioinformatic analysis of EST data of Solanaceae species revealed the presence of at least 11 miRNAs and 54 target genes in pepper (Capsicum annuum L.), 22 miRNAs and 221 target genes in potato (Solanum tuberosum L.), 12 miRNAs and 417 target genes in tomato (Solanum lycopersicum L.), 46 miRNAs and 60 target genes in tobacco (Nicotiana tabacum L.), and 7 miRNAs and 28 target genes in Nicotiana benthamiana. The identified Solanaceae miRNAs and their target genes were deposited in the SolmiRNA database, which is freely available for academic research only at http://genepool.kribb.re.kr/SolmiRNA . Our data indicate that the Solanaceae family has both conserved and specific miRNAs and that their target genes may play important roles in growth and development of Solanaceae plants.
Exercise-induced protection of bone marrow cells following exposure to radiation
Authors: De Lisio Michael , Phan Nghi , Boreham Douglas R. , Parise Gianni
Published: February 2011

The hormetic effects of exercise training have previously been shown to enhance cellular protection against oxidative stress. Therefore, adaptations to exercise training may attenuate the harmful effects of radiation induced by oxidative stress. Flow cytometric analysis of genotoxicity (γH2AX foci and micronucleated reticulocytes (MN-RET)) and cytotoxicity (apoptosis and percentage of reticulocytes) were conducted on bone marrow cells isolated from acutely exercised (Acute EX), exercise-trained (EX), and sedentary (SED) mice following 1 and 2 Gy radiation challenges in vitro. Acute EX increased the percentage of cells with activated caspase-3 and -7 (32%, p < 0.001) and γH2AX foci formation in response to 2 Gy radiation challenge (10%, p < 0.05). Exercise training significantly attenuated γH2AX foci formation and MN-RET production in response to 1 Gy radiation challenge (18%, p < 0.05 and 22%, p < 0.05, respectively). Exercise training also significantly reduced basal percentages of cells with activated caspase-3 and -7 and in response to radiation in bone marrow cells (11%, p < 0.05). These results suggest that oxidative stress caused by acute exercise induces an adaptive response responsible for the radioprotective effects of exercise training.
Changes in calcium status in aged rats fed Lactobacillus GG and Bifidobacterium lactis and oligofructose-enriched inulin
Authors: Naughton Violetta , McSorley Emeir , Naughton Patrick J.
Published: February 2011

In this study we hypothesized that an increase in numbers of beneficial bacteria in the large intestine can affect calcium (Ca) status in the elderly. Adult and aged rats were fed a diet with or without synbiotics for 21 days. Synbiotics increased the numbers of lactobacilli and bifidobacteria in large intestine in both adult and aged rats. The plasma Ca concentration was significantly increased while osteocalcin concentration was significantly decreased only in aged rats fed synbiotics.
NF-κB activation in organs from STZ-treated rats
Authors: Locke Marius , Anderson Jocelyn
Published: February 2011

Nuclear factor kappa B (NF-κB) is a ubiquitously expressed transcription factor comprised of various subunits (p50 (NF-κB1), p52 (NF-κB2), p65 (RelA), RelB, and c-Rel). Activation of certain NF-κB subunits appears to foster an inflammatory state that may promote the development of disease. Thus characterizing the specific NF-κB subunits may provide insight into the pathogenesis of certain diseases. The purpose of this study was to determine if 1 month of a diabetic state, induced by streptozotocin (STZ) treatment, alters the constitutive level of NF-κB activation, its subunit composition, or the content of NF-κB-related proteins in rodent liver, kidney, spleen, and heart. Diabetes was induced in male Sprague–Dawley rats by a single tail vein injection of STZ (55 mg·kg–1body weight). After 30 days, the heart, liver, spleen, and kidney were assessed for NF-κB activation and subunit composition with electrophoretic mobility shift assay (EMSA), and p50 and p65 subunit content was assessed with Western blotting. In diabetic animals, the constitutive level of NF-κB activation was reduced in liver, but was unchanged in kidney, spleen, and heart. EMSA supershifts showed the predominant subunit in the activated NF-κB complexes from both diabetic and control animals to be p50, although the p65 subunit was detected in NF-κB complexes from diabetic hearts. The content of p50 was unaltered in all diabetic tissues examined, whereas the content of p65 was increased only in hearts from diabetic animals. These findings support the idea that a diabetic state may induce specific changes in NF-κB subunit composition in certain tissues.
Association between exercise hemodynamics and changes in local vascular function following acute exercise
Authors: Gonzales Joaquin U. , Thompson Benjamin C. , Thistlethwaite John R. , Scheuermann Barry W.
Published: February 2011

Skeletal muscle contractions are associated with physical stimuli that act upon muscle vasculature, including increased shear stress and blood pressure. It is unclear if acute dynamic exercise alters local vascular function. The purpose of this study was to examine the role of exercise hemodynamics on the effects of acute exercise on vascular function, as evaluated by brachial artery flow-mediated dilation (FMD). Healthy individuals (n = 14; age, 18–34 years) performed 30 min of handgrip exercise at fast and slow contractions. Blood pressure during exercise was measured using a Vasotrac system (Medwave Inc.), while shear rate during exercise and FMD at rest and after 30 min of recovery from exercise were measured in the brachial artery of the active arm using Doppler ultrasound. Estimated contractile work was correlated with blood pressure (r = 0.61, p < 0.01) and retrograde shear rate (r = –0.78, p < 0.01). As a result, blood pressure was higher (p < 0.05) and oscillatory shear index was lower (p < 0.05) during slow as compared with fast contractions. On average, FMD was unchanged following fast contractions (5.4 ± 3.4%dilation to 6.1 ± 3.8%dilation; p = 0.19), but significantly reduced following slow contractions (6.9 ± 4.2%dilation to 3.6 ± 2.5%dilation; p = 0.01). Within slow contractions, subgroup analysis revealed blood pressure to associate with the change in FMD; such that individuals with mean blood pressure >100 mm Hg (range, 102–139 mm Hg) during exercise had larger decreases in FMD than individuals with lower exercise blood pressure. These results indicate that impaired local vascular function following acute exercise with high contractile activity is associated with blood pressure stimuli in healthy individuals
Nouvelles Directives canadiennes en matière d’activité physique
Authors: Tremblay Mark S. , Warburton Darren E.R. , Janssen Ian , Paterson Donald H. , Latimer Amy E. , Rhodes Ryan E. , Kho Michelle E. , Hicks Audrey , LeBlanc Allana G. , Zehr Lori , Murumets Kelly , Duggan Mary
Published: February 2011

La Société canadienne de physiologie de l’exercice (SCPE) en collaboration avec ParticipACTION et des parties prenantes et avec l’appui de l’Agence de santé publique du Canada (ASPC) a élaboré de nouvelles Directives canadiennes en matière d’activité physique à l’intention des enfants (âgés de 5 à 11 ans), des jeunes (âgés de 12 à 17 ans), des adultes (âgés de 18 à 64 ans) et des aînés (âgés de 65 ans et plus). Les nouvelles directives sont composées d’un préambule situant le contexte et de directives spécifiques à chaque tranche d’âge. L’élaboration complète des directives a respecté la Grille II d’évaluation de la qualité des recommandations pour la pratique clinique (AGREE), un outil reconnu internationalement pour l’élaboration des lignes directrices en pratique clinique. L’élaboration des directives résulte d’un processus rigoureux et transparent. Les recommandations présentées dans cet article sont basées sur les données probantes relevées dans trois analyses documentaires systématiques, et les directives finales ont bénéficié des fruits d’une vaste consultation en ligne et en personne auprès de centaines d’intervenants concernés et de sources de premier plan, sur la scène nationale et internationale. Depuis 2006, les résultats de nos efforts se retrouvent entre autres dans 21 articles (dont 5 analyses documentaires systématiques) sanctionnés par des pairs. La démarche entreprise par les chercheurs canadiens pour la mise à jour des directives en matière d’activité physique a abouti à la synthèse, l’interprétation et l’application des données probantes les plus récentes à ce jour.
Optimum compromise among environmental dispute issues using attitude based negotiation
Authors: Yousefi Saied , Hipel Keith W. , Hegazy Tarek
Published: February 2011

An innovative tactical negotiation methodology is presented for managing environmental disputes that involve multiple decision makers and multiple conflicting issues. A unique feature of the proposed negotiation methodology is that it takes into account the attitudes of the decision makers, which is an important psychological factor often ignored in traditional conflict resolution methods. A utility analysis is used to develop the methodology, which maximizes the sum of all decision makers’ utility through pair-wise negotiations with respect to each conflicting issue. A real-life environmental dispute is used to illustrate the proposed methodology and to demonstrate the benefits of incorporating attitudes into the negotiation. The proposed attitude-based negotiation constitutes a new systems engineering methodology that will assist environmental professionals in tackling real-world controversies, and provides a mechanism to examine the impact of attitudes on negotiation outcomes.
Investigation of an externally restrained concrete bridge deck slab on a multi-girder bridge model
Authors: Newhook John , Gaudet Judy , Edalatmanesh Rahman
Published: February 2011

The steel-free bridge deck system is an innovative solution in which the concrete deck slab is externally restrained by a series of steel straps. The ultimate strength characteristics of externally reinforced concrete bridge deck slabs were investigated in this paper. A 1/3 scale experimental model of a bridge with six girders was constructed for the study. This was the first known set of test results on a bridge model with more than four girders. A single point load, simulating the dual tire print of the CHBDC design truck, was applied at various locations on the deck and loading increased until punching failure occurred. The influence of different parameters including transverse diaphragms, proximity for the load to restraint straps, residual strength after strap removal, and simultaneous application of wheel loads in adjacent panels of the deck was tested to obtain a comprehensive understanding of the resistance of this deck system. The testing results confirmed that the interior panels of the deck have inherently higher punching resistance than the exterior panels. Most significantly, the study provided significant statistical data on the punching resistance of these deck slabs.
Structure of the H1 C-terminal domain and function in chromatin condensationThis paper is one of a selection of papers published in a Special Issue entitled 31st Annual International Asilomar Chromatin and Chromosomes Conference, and has undergone the Journal’s usual peer review process.
Authors: Caterino Tamara L. , Hayes Jeffrey J.
Published: February 2011

Linker histones are multifunctional proteins that are involved in a myriad of processes ranging from stabilizing the folding and condensation of chromatin to playing a direct role in regulating gene expression. However, how this class of enigmatic proteins binds in chromatin and accomplishes these functions remains unclear. Here we review data regarding the H1 structure and function in chromatin, with special emphasis on the C-terminal domain (CTD), which typically encompasses approximately half of the mass of the linker histone and includes a large excess of positively charged residues. Owing to its amino acid composition, the CTD was previously proposed to function in chromatin as an unstructured polycation. However, structural studies have shown that the CTD adopts detectable secondary structure when interacting with DNA and macromolecular crowding agents. We describe classic and recent experiments defining the function of this domain in chromatin folding and emerging data indicating that the function of this protein may be linked to intrinsic disorder.
Heterochromatin and the DNA damage response: the need to relaxThis paper is one of a selection of papers in a Special Issue entitled 31st Annual International Asilomar Chromatin and Chromosomes Conference, and has undergone the Journal’s usual peer review process.
Authors: Cann Kendra L. , Dellaire Graham
Published: February 2011

Higher order chromatin structure has an impact on all nuclear functions, including the DNA damage response. Over the past several years, it has become increasingly clear that heterochromatin and euchromatin represent separate entities with respect to both damage sensitivity and repair. The chromatin compaction present in heterochromatin helps to protect this DNA from damage; however, when lesions do occur, the compaction restricts the ability of DNA damage response proteins to access the site, as evidenced by its ability to block the expansion of H2AX phosphorylation. As such, DNA damage in heterochromatin is refractory to repair, which requires the surrounding chromatin structure to be decondensed. In the case of DNA double-strand breaks, this relaxation is at least partially mediated by the ATM kinase phosphorylating and inhibiting the function of the transcriptional repressor KAP1. This review will focus on the functions of KAP1 and other proteins involved in the maintenance or restriction of heterochromatin, including HP1 and TIP60, in the DNA damage response. As heterochromatin is important for maintaining genomic stability, cells must maintain a delicate balance between allowing repair factors access to these regions and ensuring that these regions retain their organization to prevent increased DNA damage and chromosomal mutations.
WSTF does it all: a multifunctional protein in transcription, repair, and replicationThis paper is one of a selection of papers published in a Special Issue entitled 31st Annual International Asilomar Chromatin and Chromosomes Conference, and has undergone the Journal’s usual peer review process.
Authors: Barnett Chris , Krebs Jocelyn E.
Published: February 2011

Williams syndrome transcription factor (WSTF) has emerged as an incredibly versatile nuclear protein. WSTF and the ATP-dependent chromatin remodeling complexes in which it exists, WINAC, WICH, and B-WICH, have been studied in a variety of organisms. This research has revealed roles for WSTF in a number of diverse molecular events. WSTF function includes chromatin assembly, RNA polymerase I and III gene regulation, vitamin D metabolism, and DNA repair. In addition to functioning as a subunit of several ATP-dependent chromatin remodeling complexes, WSTF binds specifically to acetylated histones and is itself a histone kinase as well as a target of phosphorylation. This review will describe the three known WSTF-containing complexes and discuss their various roles as well as mechanisms of regulating WSTF activity.
Prevalence of putative virulence markers inCampylobacter jejuniandCampylobacter coliisolated from hospitalized children, raw chicken, and raw beef in Tehran, Iran
Authors: Hamidian Mohammad , Sanaei Maryam , Bolfion Mehdi , Dabiri Hossein , Zali Mohammad-Reza , Walther-Rasmussen Jan
Published: February 2011

The incidence of the virulence-associated genes cdtA, cdtB, cdtC, cadF, dnaJ, racR, and pldA has been investigated in Campylobacter jejuni and Campylobacter coli collected from raw chicken and beef from retailers in Tehran, Iran, and from hospitalized children (age, ≤14 years) suffering from diarrhea. Campylobacter spp. were collectively identified by morphological and biochemical methods. Campylobacter jejuni and C. coli were discriminated from other Campylobacter spp. by amplification of a specific conserved fragment of the 16S rRNA gene. The distinction between C. jejuni and C. coli was subsequently made by molecular determination of the presence of the hipO gene in C. jejuni or the ask gene in C. coli. Fragments of the studied virulence-associated genes, cdtA, cdtB, cdtC, cadF, racR, dnaJ, and pldA, were amplified by PCR and subjected to horizontal gel electrophoresis. A total of 71 isolates of C. jejuni and 24 isolates of C. coli from meat were analyzed, while the numbers of isolates from the hospitalized children were 28 and 9, respectively. The unequal distribution of C. jejuni and C. coli in the samples has also been reported in other studies. Statistical analyses by the use of the two-tailed Fisher’s exact test of the occurrence of the virulence genes in the isolates of different origins showed that the occurrence of the dnaJ gene was consistently significantly higher in all C. jejuni isolates than in C. coli. The occurrence of the other virulence markers did not differ significantly between species in the majority of the isolates. The PCR results also showed that the occurrence of the virulence markers in the analyzed isolates was much lower than in other studies, which may be caused by a divergent genomic pool of our isolates in comparison with others.
Screening for lectin-like protein-producing microorganisms based on cell surface proteins
Authors: Imase Masato , Watanabe Keiji , Kitamura Takuya , Tanaka Hideo , Aoyagi Hideki
Published: February 2011

A method for screening lectin-producing microorganisms was developed. The presence of lectin on microbial cell surfaces was used as an index for their selective isolation. The lectin-producing microorganisms adhered to sugar-modified agarose beads and were selectively eluted with specific saccharide solutions. Spin columns were an effective tool for excluding non-lectin producers. Eighty-seven percent of the microorganisms that were eluted from the beads showed hemagglutination. The results of sequence analysis indicated that some of the eluted microorganisms have not been previously identified as lectin-producing microorganisms.
An association between ear and tail morphologies of bats and their foraging style
Authors: Gardiner James D. , Codd Jonathan R. , Nudds Robert L.
Published: February 2011

Most studies relating bat morphology to flight ecology have concentrated on the wing membrane. Here, canonical variance analysis showed that the ear and tail morphologies of bats also strongly relate to foraging strategy, which in turn is correlated with flight style. Variations in tail membrane morphology are likely to be a trade-off between increases in the mechanical cost of flight and improvements in foraging and flight performance. Flying with large ears is also potentially energetically expensive, particularly at high flight speeds. Large ears, therefore, are only likely to be affordable for slow foraging gleaning bat species. Bats with faster foraging flight styles tend to have smaller ears, possibly to cut the overall drag produced and reduce the power required for flight. Variations in the size of ears and tail membranes appear to be driven primarily by foraging strategy and not by body size, because the scaling relationships found are either weak or not significant. Ear size in bats may be a result of a trade-off between acoustic and aerodynamic performance.
Intraspecific comparison of diet of California sea lions (Zalophus californianus) assessed using fecal and stable isotope analyses
Authors: Orr A. J. , VanBlaricom G. R. , DeLong R. L. , Cruz-Escalona V. H. , Newsome S. D.
Published: February 2011

The diet of juvenile and adult female California sea lions ( Zalophus californianus (Lesson, 1828)) at San Miguel Island, California, was estimated and compared using fecal and stable isotope analyses to determine dietary differences by age. Fecal samples were collected during 2002–2006 and prey remains were identified. Stable carbon (δ13C) and stable nitrogen (δ15N) isotope values were determined from plasma and fur obtained from yearlings, 2- to 3-year-old juveniles, and adult females during 2005 and 2006. Juveniles ate more than 15 prey taxa, whereas adult females consumed more than 33 taxa. Relative importance of prey was determined using percent frequency of occurrence (%FO). Engraulis mordax Girard, 1854, Sardinops sagax (Jenyns, 1842), Merluccius productus (Ayres, 1855), genus Sebastes Cuvier, 1829, and Loligo opalescens Berry, 1911 were the most frequently occurring (%FO > 10%) prey in the feces of both juvenile and adult female sea lions, although their importance varied between age groups. Only yearlings had significantly different isotopic values than older conspecifics, indicating that older juveniles were feeding at a similar trophic level and in similar habitats as adult females. Whereas each method had biases, combining the two provided a better understanding of the diet of California sea lions and intraspecific differences.
Quality of mature aspen and maple forests for breeding Yellow-bellied Sapsuckers (Sphyrapicus varius)
Authors: Tozer Douglas C. , Nol Erica , Burke Dawn M.
Published: February 2011

Mature aspen (genus Populus L..) and maple (genus Acer L.) forests appear to be high-quality breeding habitat for Yellow-bellied Sapsuckers ( Sphyrapicus varius (L., 1766)). To explore some of the mechanisms that influence quality of the breeding habitat, we measured demographic and breeding resources in four forest stands each of 95-year-old quaking aspen ( Populus tremuloides Michx.) and 182-year-old sugar maple ( Acer saccharum Marsh.) in Algonquin Provincial Park, Ontario, from 2007 to 2009. Population density was higher, egg laying earlier, clutches larger, hatching success greater, and per capita and population fledgling production higher in maple stands compared with aspen stands. Longer nest-building and prelaying stages in aspen stands delayed egg laying by 5 days relative to maple stands. The delay in egg laying in aspen stands may have been caused by lower quality sap resources, which then resulted in lower productivity. Adults delivered smaller food loads to nests in aspen stands than in maple stands, which may have increased nestling mortality in aspen stands. Although per capita fledgling production was lower in aspen stands than in maple stands, Yellow-bellied Sapsuckers in both forests were able to replace themselves, suggesting that mature deciduous and mixed-deciduous forests, in general, are high-quality breeding habitat for this sapsucker.
STRANGENESS PHYSICS WITH CLAS
Authors: Burkert Volker D.
Published: February 2011

A brief overview of strangeness physics with the CLAS detector at JLab is given, mainly covering the domain of nucleon resonances. Several excited states predicted by the symmetric constituent quark model may have significant couplings to the KΛ or KΣ channels. We will discuss data that are relevant in the search for such states in the strangeness channel, and give an outlook on the future prospects of the N * program at JLab with electromagnetic probes.
RESULTS ON STRANGENESS PRODUCTION FROM HADES
Authors:   For the HADES Collaboration, Schmah A.
Published: February 2011

Recent results concerning the production of K +, K -, ø, [Formula: see text] and Λ particles in the reaction system Ar + KCl at 1.76 AGeV measured by the HADES Collaboration are presented. Transverse momentum distributions have been measured in a large fraction of the phase space. For the first time, at SIS energies, K +, K - and ɸ mesons have been measured independently and the slope parameter for ø mesons could be extracted. A large set of statistics has been collected for the produced [Formula: see text] and Λ in the phase space region around mid-rapidity. The high quality of these data render them very suitable for comparisons with theoretical models.
PRODUCTION AND SEARCHES FOR CASCADE BARYONS WITH CLAS
Authors:   For the CLAS Collaboration, Smith Elton S.
Published: February 2011

We present the results of photoproduction cross sections of the ground state cascade Ξ- and the first excited state Ξ*-(1530) measured with the CLAS detector. The photoproduction of the cascade resonances has been investigated in the reactions γp → K+K+(X) and γp → K+K+π-(X). The differential and total cross sections of the Ξ- were determined for photon beam energies from 2.75 to 4.75 GeV and are consistent with a production mechanism of Y* → K+Ξ- through a t-channel process. The cross-section of the Ξ*-(1530) has been determined for photon beam energies from 3.35 to 4.75 GeV. The reaction γp → K+K+π-(Ξ0) has also been investigated in the search for excited cascade resonances decaying to π-Ξ0. No significant signal of excited cascade states other than the well-known Ξ*-(1530) is observed.

We also present the latest results of a search for the Φ--(1862) exotic pentaquark state in a photoproduction experiment on a deuterium target. A high-statistics sample of π-Ξ- events have been collected and analyzed. A preliminary invariant mass spectrum of the π-Ξ- system is presented, which is used to set upper limits on the photoproduction of the Φ-- pentaquark state.
Ξ12C(0+) AND Ξ16O POTENTIALS DERIVED FROM THE SU6 QUARK-MODEL BARYON-BARYON INTERACTION
Authors: Fujiwara Y. , Kohno M. , Suzuki Y.
Published: February 2011

We derive single-hyperon potentials for light nuclei, based on the G-matrix calculations of the quark-model baryon-baryon interactions developed by the Kyoto-Niigata group. The Ξ12 C (0+) and Ξ16 O potentials have non-trivial oscillating behavior, reflecting strong isospin dependence of the ΞN interaction; namely, attractive isospin I = 0 ΞN interaction and weakly repulsive I = 1 interaction. The latter repulsive effect is largely enhanced in the intermediate region of the Ξ-core potential, resulting in very weak attraction at the surface region.
HYPERNUCLEI WITH A MICROSCOPIC LAMBDA-NUCLEON FORCE
Authors: Schulze H.-J. , Sagawa H.
Published: February 2011

We study properties of Λ hypernuclei in an extended Skyrme-Hartree-Fock model employing recent modern nucleonic Skyrme forces together with a microscopic lambda-nucleon interaction derived from Brueckner-Hartree-Fock calculations of hypernuclear matter with the Nijmegen soft-core hyperon-nucleon potentials. We show in particular recent results of deformed and neutron-rich hypernuclei close to the dripline.
NEW RESULTS ON NONMESONIC WEAK DECAY OF Λ HYPERNUCLEI WITH FINUDA
Authors:   For the FINUDA Collaboration, Bufalino S. , Botta E. , Bressani T. , De Mori F. , Marcello S. , Calvo D. , Feliciello A. , Filippi A. , Wheadon R. , Busso L. , Morra O. , Agnello M. , Benussi L. , Bertani M. , Fabbri F. L. , Gianotti P. , Hartmann O. , Lucherini V. , Pace E. , Pompili F. , Andronenkov A. , Palomba M. , Pantaleo A. , Paticchio V. , Dalena B. , D'Erasmo G. , Fiore E. M. , Simonetti G. , Lenti V. , Bonomi G. , Zenoni A. , Fontana A. , Genova P. , Panzarasa A. , Montagna P. , Bregant M. , Camerini P. , Rui R. , Grion N. , Piano S. , Fujioka H. , Nagae T. , Outa H. , Sekimoto M. , Toyoda A. , Maruta T. , Bhang H. C. , Kang B. , Nakajima D. , Mirfakhrai N. , Beer G. , Lorente A. Sanchez
Published: February 2011

The FINUDA experiment has performed a systematic study of the NonMesonic Weak Decay (NMWD) of Λ hypernuclei analizing all the data collected from 2003 up to 2007. The results of a measurement of the spectra of protons coming from the NMWD of [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] are the subject of this paper.
MINIMIZERS OF THE MAGNETIC GINZBURG–LANDAU FUNCTIONAL IN SIMPLY CONNECTED DOMAIN WITH PRESCRIBED DEGREE ON THE BOUNDARY
Authors: BERLYAND LEONID , MISIATS OLEKSANDR , RYBALKO VOLODYMYR
Published: February 2011

We study the minimizers of the Ginzburg–Landau free energy functional in the class (u, A) ∈ H1(Ω; ℂ) × H1(Ω; ℝ2) with |u| = 1 on ∂Ω, where Ω is a bounded simply connected domain in ℝ2. We consider the connected components of this class defined by the prescribed topological degree d of u on the boundary ∂Ω. We show that for d ≠ 0 the minimizers exist if 0 < λ ≤ 1 and do not exist if λ > 1, where λ is the coupling constant ([Formula: see text] is the Ginzburg–Landau parameter). We also establish the asymptotic locations of vortices for λ → 1 - 0 (the critical value λ = 1 is known as the Bogomol'nyi integrable case).
ON EXACT DEAD-CORE RATES FOR A SEMILINEAR HEAT EQUATION WITH STRONG ABSORPTION
Authors: SEKI YUKIHIRO
Published: February 2011

We study a semilinear heat equation with strong absorption ut = Δu - up with 0 < p < 1 in RN. A solution is known to develop dead-core in finite time for a wide class of initial data. We construct specific solutions with exact dead-core rates faster than the one given by the corresponding ODE. They are constructed formally by means of matched asymptotic expansion technique and rigorously by means of topological fixed-point arguments based on a priori estimates. To obtain the a priori estimates, we analyze a certain linearized problem in a new function space [Formula: see text].
On Graph-Based Name Disambiguation
Authors: Fan Xiaoming , Wang Jianyong , Pu Xu , Zhou Lizhu , Lv Bing
Published: February 2011

Name ambiguity stems from the fact that many people or objects share identical names in the real world. Such name ambiguity decreases the performance of document retrieval, Web search, information integration, and may cause confusion in other applications. Due to the same name spellings and lack of information, it is a nontrivial task to distinguish them accurately. In this article, we focus on investigating the problem in digital libraries to distinguish publications written by authors with identical names. We present an effective framework named GHOST (abbreviation for GrapHical framewOrk for name diSambiguaTion), to solve the problem systematically. We devise a novel similarity metric, and utilize only one type of attribute (i.e., coauthorship) in GHOST. Given the similarity matrix, intermediate results are grouped into clusters with a recently introduced powerful clustering algorithm called
Affinity Propagation
. In addition, as a complementary technique, user feedback can be used to enhance the performance. We evaluated the framework on the real DBLP and PubMed datasets, and the experimental results show that GHOST can achieve both high
precision
and
recall
.
Efficient rare event simulation for heavy-tailed compound sums
Authors: Blanchet Jose , Li Chenxin
Published: February 2011

We develop an efficient importance sampling algorithm for estimating the tail distribution of heavy-tailed compound sums, that is, random variables of the form
S

M

=
Z
1
+…+
Z

M

where the
Z

i

's are independently and identically distributed (i.i.d.) random variables in R and
M
is a nonnegative, integer-valued random variable independent of the
Z

i

's. We construct the first estimator that can be rigorously shown to be strongly efficient only under the assumption that the
Z

i

's are subexponential and
M
is light-tailed. Our estimator is based on state-dependent importance sampling and we use Lyapunov-type inequalities to control its second moment. The performance of our estimator is empirically illustrated in various instances involving popular heavy-tailed models.
The double CFTP method
Authors: Devroye Luc , James Lancelot F.
Published: February 2011

We consider the problem of the exact simulation of random variablesZthat satisfy the distributional identityZ=LVY+ (1-V)Z, whereV∈ [0,1] andYare independent, and =Ldenotes equality in distribution. Equivalently,Zis the limit of a Markov chain driven by that map. We give an algorithm that can be automated under the condition that we have a source capable of generating independent copies ofY, and thatVhas a density that can be evaluated in a black-box format. The method uses a doubling trick for inducing coalescence in coupling from the past. Applications include exact samplers for many Dirichlet means, some two-parameter Poisson--Dirichlet means, and a host of other distributions related to occupation times of Bessel bridges that can be described by stochastic fixed point equations.
Forwarding devices
Authors: Chertov Roman , Fahmy Sonia
Published: February 2011

Most popular simulation and emulation tools use high-level models of forwarding behavior in switches and routers, and give little guidance on setting model parameters such as buffer sizes. Thus, a myriad of papers report results that are highly sensitive to the forwarding model or buffer size used. Incorrect conclusions are often drawn from these results about transport or application protocol performance, service provisioning, or vulnerability to attacks. In this article, we argue that measurement-based models for routers and other forwarding devices are necessary. We devise such a model and validate it with measurements from three types of Cisco routers and one Juniper router, under varying traffic conditions. The structure of our model is device-independent, but the model uses device specific parameters. The compactness of the parameters and simplicity of the model make it versatile for high-fidelity simulations that preserve simulation scalability. We construct a profiler to infer the parameters within a few hours. Our results indicate that our model approximates different types of routers significantly better than the default ns-2 simulator models. The results also indicate that queue characteristics vary dramatically among the devices we measure, and that backplane contention can be a factor.
A variant of importance splitting for rare event estimation
Authors: Amrein Michael , Künsch Hans R.
Published: February 2011

Importance splitting is a simulation technique to estimate very small entrance probabilities for Markov processes by splitting sample paths at various stages before reaching the set of interest. This can be done in many ways, yielding different variants of the method. In this context, we propose a new one, called fixed number of successes. We prove unbiasedness for the new and some known variants, because in many papers, the proof is based on an incorrect argument. Further, we analyze its behavior in a simplified setting in terms of efficiency and asymptotics in comparison to the standard variant. The main difference is that it controls the imprecision of the estimator rather than the computational effort. Our analysis and simulation examples show that it is rather robust in terms of parameter choice and we present a two-stage procedure which also yields confidence intervals.
On deriving and incorporating multihop path duration estimates in VANET protocols
Authors: Nzouonta Josiane , Nakayama Marvin K. , Borcea Cristian
Published: February 2011

The expected duration of multihop paths can be incorporated at different layers in the protocol stack to improve the performance of mobile ad hoc networks. This article presents two discrete-time and discrete-space Markov chain-based methods, DTMC-CA and DTMC-MFT, to estimate the duration of multihop road-based paths in vehicular ad hoc networks (VANET). The duration of such paths does not depend on individual nodes because packets can be forwarded by any vehicle located along the roads forming the path. DTMC-CA derives probabilistic measures based only on vehicle density for a traffic mobility model, which in this article is the microscopic Cellular Automaton (CA) freeway traffic model. DTMC-MFT generalizes the approach used by DTMC-CA to any vehicular mobility model by focusing on the macroscopic information of vehicles rather than their microscopic characteristics. The proposed analytical models produce performance-measure values comparable to simulation estimates from the validated CA traffic model. Furthermore, this article demonstrates the benefits of incorporating expected path durations into a VANET routing protocol. Simulation results show that the network overhead associated with route maintenance can be reduced to less than half by using the expected path durations.
Performance, overhead, and packetization characteristics of Java application level protocols
Authors: Pendergast Mark
Published: February 2011

This paper presents the results of a set of performance tests designed to determine the relative efficiencies of five different Java application level protocols used for peer-to-peer communications. Efficiency was determined by measuring transmission latency, number of packets sent, packetization of data, and bytes transmitted. The protocols tested include: datagram (UDP), DataStreams, ObjectStreams, Remote Method invocation, and Piped Streams. The tests revealed a great variation in packetization efficiency and latency between the protocols. A new record oriented data stream is proposed and prototyped and testing. Preliminary performance tests showed this new record oriented data stream to be several times more efficient than ObjectStreams.
Listen before you talk, but on the frequency domain
Authors: Sen Souvik , Choudhury Romit Roy , Nelakuditi Srihari
Published: February 2011

WiFi networks adopt a random backoff mechanism to mediate channel contention. Although effective, backing off has been shown to reduce channel utilization. This is because backing off occurs in the time domain, forcing the channel to remain idle for multiple time slots. This poster proposes to break away from convention, and recreate the time domain operations in the frequency domain. Our basic idea is to pretend that OFDM subcarriers are integer numbers, and hence, counting down from a random backoff value may be equivalent to transmitting on a randomly chosen subcarrier. By looking at all active subcarriers and comparing with one's own chosen subcarrier, it is possible to select the winner of the contention. In fact, a logical ordering among nodes is feasible, enabling a train of scheduled transmissions from only one round of contention. We develop these ideas into a T2F protocol and prototype it on a small testbed of 5 USRPs. Early experimental results confirm its feasibility, along with promising throughput gains of up to 50%.
Modeling of internet usage in large mobile societies using self-organizing maps
Authors: Moghaddam Saeed , Helmy Ahmed
Published: February 2011

User online behavior and interests will play a central role in future mobile networks. We propose a systematic method based on self-organizing maps (SOM) for multi-dimensional modeling and analysis of online activity for thousands of mobile users over a variety of web domains across several buildings. We find surprisingly that users' trends based on domains and locations can be accurately modeled using self-organizing maps with clearly distinct characteristics. We also find many non-trivial correlations between different types of web domains and locations. The results of our work can be applied for realistic simulation and design of large mobile societies.
Balancing broadcast reliability and transmission range in VANETs
Authors: Lu Hongsheng , Poellabauer Christian
Published: February 2011

A novel transmit power control protocol for vehicular ad-hoc networks (VANETs) called Efficient Transmit Power Control (ETPC) is proposed in this poster. It aims to improve the reliability of safety-critical broadcasts while also maximizing the transmission range. On one hand, large transmission ranges are often desirable to ensure that safety-critical messages reach as many vehicles as possible. On the other hand, they also lead to increased channel contention and packet collisions, especially in dense networks. As a consequence, this work proposes an adaptive transmit power control approach that balances these two conflicting goals. The approach incurs minimum additional overhead (since it is primarily based on simple overhearing) and works well in both highway and urban traffic scenarios.
SearchLight
Authors: Bakht Mehedi , Kravets Robin
Published: February 2011

The usefulness of proximity-based social networking applications is limited by the lack of effective and energy efficient neighbor discovery protocols. While probabilistic approaches perform well for the average case, they exhibit long tails resulting in high upper bounds on neighbor discovery latency. On the other hand, recent deterministic protocols like Disco and U-Connect improve on the worst case bound, but do so by sacrificing average case performance. In response to these limitations, we present Searchlight, an asynchronous neighbor discovery protocol that combines both deterministic and probabilistic components, and thereby achieves an average case performance comparable to the probabilistic approaches while improving on the deterministic worst case bounds.
SMOOTH
Authors: Munjal Aarti , Camp Tracy , Navidi William C.
Published: February 2011

In addition to being realistic, a mobility model should be easy to understand and use. Unfortunately, most of the simple mobility models proposed thus far are not realistic and most of the realistic mobility models proposed thus far are not simple to use. In this work, we present SMOOTH, a new mobility model that is realistic and simple to use. SMOOTH imitates a recently published mobility model, SLAW, that is realistic but not simple to use. While SLAW was constructed by extracting statistical features of real human movement, it has input parameters that are very complex to set. SMOOTH, on the other hand, is realistic (as SMOOTH is based on the real GPS traces used by SLAW) and is simple to use (as SMOOTH avoids SLAW's complex input parameter.
Towards an optimal malware defense system for DTN with heterogeneous devices
Authors: Li Yong , Gong Yu , Jin Depeng , Su Li , Zeng Lieguang , Hui Pan
Published: February 2011

As malware attacks become more popular in mobile handsets formed Delay Tolerant Networks (DTN), deploying an efficient defense system for helping the infected nodes to kill the malwares is important to prevent serious spreading and outbreak. In reality, the handset devices are heterogeneous in terms of operate systems, the malwares infect the targeted system in any opportunistic ways via local and global connectivity, while the to-be-deployed defense system is usually resource-limited. These points makes this problem technically challenging. In this paper, we investigate the problem of optimal malware defense system deployment with realistic assumptions that specific types of malwares can only infect the targeted system and the capacity of the defense system is limited, which are usually ignored in previous analytical work for simplicity reason. Based on the proposed framework of optimizing the anti-malware software allocation for the defense system, we give a greedy algorithm to obtain the optimal solution.
TPC-E vs. TPC-C
Authors: Chen Shimin , Ailamaki Anastasia , Athanassoulis Manos , Gibbons Phillip B. , Johnson Ryan , Pandis Ippokratis , Stoica Radu
Published: February 2011

TPC-E is a new OLTP benchmark recently approved by the Transaction Processing Performance Council (TPC). In this paper, we compare TPC-E with the familiar TPCC benchmark in order to understand the behavior of the new TPC-E benchmark. In particular, we compare the I/O access patterns of the two benchmarks by analyzing two OLTP disk traces. We find that (i) TPC-E is more read intensive with a 9.7:1 I/O read to write ratio, while TPC-C sees a 1.9:1 read-to-write ratio; and (ii) although TPC-E uses pseudo-realistic data, TPC-E's I/O access pattern is as random as TPC-C. The latter suggests that like TPC-C, TPC-E can benefit from SSDs, which have superior random I/O support. To verify this, we replay both disk traces on an Intel X25-E SSD and see dramatic improvements for both TPC-C and TPC-E.
Emerging multidisciplinary research across database management systems
Authors: Nica Anisoara , Suchanek Fabian M. , Varde Aparna S.
Published: February 2011

The database community is exploring more and more multidisciplinary avenues: Data semantics overlaps with ontology management; reasoning tasks venture into the domain of artificial intelligence; and data stream management and information retrieval shake hands, e.g., when processing Web click-streams. These new research avenues become evident, for example, in the topics that doctoral students choose for their dissertations. This paper surveys the emerging multidisciplinary research by doctoral students in database systems and related areas. It is based on the PIKM 2010, which is the 3rd Ph.D. workshop at the International Conference on Information and Knowledge Management (CIKM). The topics addressed include ontology development, data streams, natural language processing, medical databases, green energy, cloud computing, and exploratory search. In addition to core ideas from the workshop, we list some open research questions in these multidisciplinary areas.
The hitchhiker's guide to software languages
Authors: Lämmel Ralf
Published: February 2011

There is only that much space in the CS curriculum, and there are always new subjects that should be accommodated by the curriculum. For instance, in our community, we would want all graduates to leave university with a modest background in technical spaces, software languages, and meta-programming; also, with conceptually informed and reasonably timeless skills to efficiently master related programming techniques and technologies. In reality, the curricula of few CS departments meet this expectation. In this talk, I will discuss such curricula-related expectations of our community and the suboptimal situation at CS departments---as perceive them. More importantly, I will allude to a revision of the CS curriculum that could optimize matters and may stand a chance for mid-term adoption.