bluuebunny/crossref_metadata_2025 huggingface dataset:
Thymic stromal lymphopoietin
Authors: He Rui , Geha Raif S.
Published: January 2010

Thymic stromal lymphopoietin (TSLP) is an epithelial cell‐derived cytokine expressed in skin, gut, lungs, and thymus. TSLP signals via a TSLP receptor (TSLPR), a heterodimer of the IL‐7 receptor α chain and the TSLPR chain. The TSLPR chain is closely related to the common receptor γ chain that is expressed on a wide range of cell types in the adaptive and innate immune system. TSLP exerts a profound influence on the polarization of dendritic cells to drive T helper (Th) 2 cytokine production. TSLP also directly promotes T‐cell proliferation in response to T‐cell receptor activation and Th2 cytokine production and supports B‐cell expansion and differentiation. TSLP further amplifies Th2 cytokine production by mast cells and natural killer T cells. These properties confer on TSLP a critical role in driving Th2‐mediated inflammation. This role is supported by the finding that TSLP expression is upregulated in keratinocytes of atopic dermatitis skin lesions and in bronchial epithelial cells in asthma.
Plasmacytoid dendritic cells: key players in the initiation and regulation of immune responses
Authors: Lande Roberto , Gilliet Michel
Published: January 2010

Plasmacytoid dendritic cells (pDCs) are a rare population of circulating cells that selectively express Toll‐like receptors (TLR)7 and TLR9 and have the capacity to produce large amounts of type I interferons (IFNs) in response to viruses or host‐derived nucleic acid‐containing complexes. Through the production of type I IFNs, pDCs initiate protective immunity by activating classical DCs, T cells, natural killer cells, and B cells. Upon activation, pDCs also differentiate into mature DCs and may contribute to the contraction of T‐cell responses. In this review, we describe how pDCs are key players in the initiation and regulation of immune responses and discuss their emerging role in the pathogenesis of human diseases.
General Geometrical Model of Scroll Compression Chamber for Scroll Fluid Machine
Authors: Jianguo Qiang
Published: January 2010

For a scroll fluid machine with an arbitrary number of scroll wraps on its individual scroll, the phase difference between adjacent scroll profiles on one scroll is defined as the characteristic angle of the scroll. Based on general profile theory, a scroll pitch line is defined as of A-type with which the outer profile of orbiting scroll and the inner profile of fixed scroll can be formed. Another scroll pitch line is defined as B-type with which the inner profile of orbiting scroll and the outer profile of fixed scroll can be formed. The scroll compression chambers corresponding to the pitch lines of A-type and that of B-type are defined as compression chambers of A-series and B-series, respectively. Then the general geometrical model of scroll compression chamber is set up. It can demonstrate the deforming, opening, and vanishing process of all scroll chambers.
Effect of Grooves on Cavitation Around the Body of Revolution
Authors: Li Yongjian , Chen Haosheng , Wang Jiadao , Chen Darong
Published: January 2010

Cavitation occurs widely in hydraulic machines, water and underwater vehicles, and lots of other equipments operating with liquids. Much research has been carried out to find out the factors affecting the degree of cavitation for better control of this phenomenon. In this study, the effects of grooves distributed around the body of revolution on cavitation are investigated using experimental and numerical methods. The experimental results show that the position and shape of the cavity clouds are affected by the dimensions of the grooves. A numerical simulation using the finite volume method indicates that the grooves influence the pressure distribution in the whole flow field and induce significant pressure fluctuation. The minimum pressure in each groove occurs on the top of the groove’s “windward” edge and decreases as the groove width is increased. Comparing the experimental and numerical results, it is found that cavitation is closely related to the local pressure of the fluid. Multiple grooves around the body of revolution induce pressure fluctuation. The groove width affects the amplitude and interval of the fluctuation and consequently influences the distribution of cavitation.
High-Resolution Numerical Simulation of Low Reynolds Number Incompressible Flow About Two Cylinders in Tandem
Authors: Singha Sintu , Sinhamahapatra K. P.
Published: January 2010

Low Reynolds number steady and unsteady incompressible flows over two circular cylinders in tandem are numerically simulated for a range of Reynolds numbers with varying gap size. The governing equations are solved on an unstructured collocated mesh using a second-order implicit finite volume method. The effects of the gap and Reynolds number on the vortex structure of the wake and on the fluid dynamic forces acting on the cylinders are reported and discussed. Both the parameters have significant influence on the flow field. An attempt is made to unify their influence on some global parameters.
Assessment of the Performance of Acoustic and Mass Balance Methods for Leak Detection in Pipelines for Transporting Liquids
Authors: Martins Jaqueline Costa , Seleghim Paulo
Published: January 2010

On-line leak detection is a main concern for the safe operation of pipelines. Acoustic and mass balance are the most important and extensively applied technologies in field problems. The objective of this work is to compare these leak detection methods with respect to a given reference situation, i.e., the same pipeline and monitoring signals acquired at the inlet and outlet ends. Experimental tests were conducted in a 749 m long laboratory pipeline transporting water as the working fluid. The instrumentation included pressure transducers and electromagnetic flowmeters. Leaks were simulated by opening solenoid valves placed at known positions and previously calibrated to produce known average leak flow rates. Results have clearly shown the limitations and advantages of each method. It is also quite clear that acoustics and mass balance technologies are, in fact, complementary. In general, an acoustic leak detection system sends out an alarm more rapidly and locates the leak more precisely, provided that the rupture of the pipeline occurs abruptly enough. On the other hand, a mass balance leak detection method is capable of quantifying the leak flow rate very accurately and of detecting progressive leaks.
Effect of Capsule Density and Concentration on Pressure Drops of Spherical Capsule Train Conveyed by Water
Authors: Ulusarslan Deniz
Published: January 2010

This experimental investigation concerns the hydraulic transport of a spherical capsule train, whose density is equal to that of water (relative density; s=1), in horizontal pipes. In a system where the carrier fluid is water, pressure drops of two phase flow and capsule velocities were measured at 0.2–1.0 m/s bulk velocities and 5–20% capsule transport concentrations. The results found were compared with the pressure gradient (pressure drops per unit length) ratios ((ΔP/L)m/(ΔP/L)w) measured for less dense capsules. The capsule velocity and the velocity ratio (Vc/Vb) increased with increasing the bulk velocity. As concentration increases, the pressure gradient of the capsule-water mixture increases. For all concentrations, the pressure gradient ratio decreases (getting closer to 1) with increasing bulk velocity. This result is similar to that of capsules with less relative density. However, the pressure gradient ratio of the capsule flow with less density is higher than that of capsules with equal density at constant transport concentrations. The reason for this difference is that the capsules with a density equal to that of water move along the axis of the pipe for a longer time. When capsules with equal density are used, the mass flow rate will remain the same, but energy consumption will decrease.
Stability of Plane Channel Flow With Viscous Heating
Authors: Sahu K. C. , Matar O. K.
Published: January 2010

The linear stability analysis of pressure-driven flow undergoing viscous heating through a channel is considered. The walls of the channel are maintained at different constant temperatures and Nahme’s law is applied to model the temperature dependence of the fluid viscosity. A modified Orr–Sommerfeld equation coupled with a linearized energy equation is derived and solved using an efficient spectral collocation method. Our results indicate that increasing the influence of viscous heating is destabilizing. It is also shown that the critical Reynolds number decreases by one order of magnitude with increase in the Nahme number. An energy analysis is conducted to understand the underlying physical mechanism of the instability.
Steiner trees and spanning trees in six-pin soap films
Authors: Dutta Prasun , Khastgir S. Pratik , Roy Anushree
Published: January 2010

The problem of finding minimum (local as well as absolute) path lengths joining given points (or terminals) on a plane is known as the Steiner problem. The Steiner problem arises in finding the minimum total road length joining several towns and cities. We study the Steiner tree problem using six-pin soap films. Experimentally, we observe spanning trees as well as Steiner trees partly by varying the pin diameter. We propose a possibly exact expression for the length of a spanning tree or a Steiner tree, which fails mysteriously in certain cases.
Can bubbles sink ships?
Authors: Hueschen Michael A.
Published: January 2010

I investigate the interplay between the buoyancy force and the upwelling (or drag) force which act on a floating object when bubbles are rising through a body of water. Bubbles reduce the buoyant force by reducing the density of the water, but if they entrain an upwelling flow of water as they rise, they can produce a large upward drag force on the floating object. In an upwelling flow, our model ship (density=0.94 g/cm3) floats in a foam whose density is only 0.75 g/cm3. Comparing results with and without upwelling currents is an interesting demonstration and has real-world applications to ships in the ocean.
Quantitative Phosphoproteomics Reveals Widespread Full Phosphorylation Site Occupancy During Mitosis
Authors: Olsen Jesper V. , Vermeulen Michiel , Santamaria Anna , Kumar Chanchal , Miller Martin L. , Jensen Lars J. , Gnad Florian , Cox Jürgen , Jensen Thomas S. , Nigg Erich A. , Brunak Søren , Mann Matthias
Published: January 2010

Protein phosphorylation during the cell cycle may be an all-or-none process in many instances.
Extensive Crosstalk Between O-GlcNAcylation and Phosphorylation Regulates Cytokinesis
Authors: Wang Zihao , Udeshi Namrata D. , Slawson Chad , Compton Philip D. , Sakabe Kaoru , Cheung Win D. , Shabanowitz Jeffrey , Hunt Donald F. , Hart Gerald W.
Published: January 2010

Protein O-GlcNAcylation regulates cell division.
BMPing Up Metabolism
Authors: VanHook Annalisa M.
Published: January 2010

BMP signaling plays a role in energy homeostasis.
Cyclic Nucleotides Converge on Brown Adipose Tissue Differentiation
Authors: Amieux Paul S. , McKnight G. Stanley
Published: January 2010

cGMP-mediated signaling pathways are required for the differentiation and function of brown adipocytes.
Distribution of Serotypes, Genotypes, and Resistance Determinants among Macrolide-Resistant
Streptococcus pneumoniae
Isolates
Authors: Xu Xiaoping , Cai Lin , Xiao Meng , Kong Fanrong , Oftadeh Shahin , Zhou Fei , Gilbert Gwendolyn L.
Published: January 2010

Macrolide resistance in
Streptococcus pneumoniae
has emerged as an important clinical problem worldwide over the past decade. The aim of this study was to analyze the phenotypes (serotype and antibiotic susceptibility), genotypes (multilocus sequence type [MLST] and antibiotic resistance gene/transposon profiles) among the 31% (102/328) of invasive isolates from children in New South Wales, Australia, in 2005 that were resistant to erythromycin. Three serotypes—19F (47 isolates [46%]), 14 (27 isolates [26%]), and 6B (12 isolates [12%])—accounted for 86 (84%) of these 102 isolates. Seventy four (73%) isolates had the macrolide-lincosamide-streptogramin B (MLS
B
) resistance phenotype and carried Tn
916
transposons (most commonly Tn
6002
); of these, 73 (99%) contained the erythromycin ribosomal methylase gene [
erm
(B)], 34 (47%) also carried the macrolide efflux gene [
mef
(E)], and 41 (55%) belonged to serotype 19F. Of 28 (27%) isolates with the M phenotype, 22 (79%) carried
mef
(A), including 16 (57%) belonging to serotype 14, and only six (19%) carried Tn
916
transposons. Most (84%) isolates which contained
mef
also contained one of the
msr
(A) homologues,
mel
or
msr
(D); 38 of 40 (95%) isolates with
mef
(E) (on
mega
) carried
mel
, and of 28 (39%) isolates with
mef
(A), 10 (39%) carried
mel
and another 11(39%) carried
msr
(D), on Tn
1207.1
. Two predominant macrolide-resistant
S. pneumoniae
clonal clusters (CCs) were identified in this population. CC-271 contained 44% of isolates, most of which belonged to serotype 19F, had the MLS
B
phenotype, were multidrug resistant, and carried transposons of the Tn
916
family; CC-15 contained 23% of isolates, most of which were serotype 14, had the M phenotype, and carried
mef
(A) on Tn
1207.1.
Erythromycin resistance among
S. pneumoniae
isolates in New South Wales is mainly due to the dissemination of multidrug-resistant
S. pneumoniae
strains or horizontal spread of the Tn
916
family of transposons.
The GenusAeromonas: Taxonomy, Pathogenicity, and Infection
Authors: Janda J. Michael , Abbott Sharon L.
Published: January 2010

Over the past decade, the genusAeromonashas undergone a number of significant changes of practical importance to clinical microbiologists and scientists alike. In parallel with the molecular revolution in microbiology, several new species have been identified on a phylogenetic basis, and the genome of the type species,A. hydrophilaATCC 7966, has been sequenced. In addition to established disease associations,Aeromonashas been shown to be a significant cause of infections associated with natural disasters (hurricanes, tsunamis, and earthquakes) and has been linked to emerging or new illnesses, including near-drowning events, prostatitis, and hemolytic-uremic syndrome. Despite these achievements, issues still remain regarding the role thatAeromonasplays in bacterial gastroenteritis, the extent to which species identification should be attempted in the clinical laboratory, and laboratory reporting of test results from contaminated body sites containing aeromonads. This article provides an extensive review of these topics, in addition to others, such as taxonomic issues, microbial pathogenicity, and antimicrobial resistance markers.
Enhanced Susceptibility to Acute Pneumococcal Otitis Media in Mice Deficient in Complement C1qa, Factor B, and Factor B/C2
Authors: Tong Hua Hua , Li Yong Xing , Stahl Gregory L. , Thurman Joshua M.
Published: January 2010

To define the roles of specific complement activation pathways in host defense against
Streptococcus pneumoniae
in acute otitis media (AOM), we investigated the susceptibility to AOM in mice deficient in complement factor B and C2 (
Bf/C2
−/
−
), C1qa (
C1qa
−/
−
), and factor B (
Bf
−
/
−
). Bacterial titers of both
S. pneumoniae
serotype 6A and 14 in the middle ear lavage fluid samples from
Bf/C2
−/
−
,
Bf
−
/
−
, and
C1qa
−/
−
mice were significantly higher than in samples from wild-type mice 24 h after transtympanical infection (
P
< 0.05) and remained persistently higher in samples from
Bf/C2
−/
−
mice than in samples from wild-type mice. Bacteremia occurred in
Bf/C2
−/
−
,
Bf
−
/
−
, and
C1qa
−/
−
mice infected with both strains, but not in wild-type mice. Recruitment of inflammatory cells was paralleled by enhanced production of inflammatory mediators in the middle ear lavage samples from
Bf/C2
−/
−
mice. C3b deposition on both strains was greatest for sera obtained from wild-type mice, followed by
C1qa
−
/
−
and
Bf
−
/
−
mice, and least for
Bf/C2
−
/
−
mice. Opsonophagocytosis and whole-blood killing capacity of both strains were significantly decreased in the presence of sera or whole blood from complement-deficient mice compared to wild-type mice. These findings indicate that both the classical and alternative complement pathways are critical for middle ear immune defense against
S. pneumoniae
. The reduced capacity of complement-mediated opsonization and phagocytosis in the complement-deficient mice appears to be responsible for the impaired clearance of
S. pneumoniae
from the middle ear and dissemination to the bloodstream during AOM.
Two Atypical Enteropathogenic
Escherichia coli
Strains Induce the Production of Secreted and Membrane-Bound Mucins To Benefit Their Own Growth at the Apical Surface of Human Mucin-Secreting Intestinal HT29-MTX Cells
Authors: Vieira Mônica A. M. , Gomes Tânia A. T. , Ferreira Antonio J. P. , Knöbl Terezinha , Servin Alain L. , Liévin-Le Moal Vanessa
Published: January 2010

In rabbit ligated ileal loops, two atypical enteropathogenic
Escherichia coli
(aEPEC) strains, 3991-1 and 0421-1, intimately associated with the cell membrane, forming the characteristic EPEC attachment and effacement lesion of the brush border, induced a mucous hypersecretion, whereas typical EPEC (tEPEC) strain E2348/69 did not. Using cultured human mucin-secreting intestinal HT29-MTX cells, we demonstrate that apically aEPEC infection is followed by increased production of secreted MUC2 and MUC5AC mucins and membrane-bound MUC3 and MUC4 mucins. The transcription of the
MUC5AC
and
MUC4
genes was transiently upregulated after aEPEC infection. We provide evidence that the apically adhering aEPEC cells exploit the mucins' increased production since they grew in the presence of membrane-bound mucins, whereas tEPEC did not. The data described herein report a putative new virulence phenomenon in aEPEC.
Indications for thoracic ultrasound in chest medicine: an observational study
Authors: Medford A R L , Entwisle J J
Published: January 2010

Introduction

Thoracic ultrasound (TUS) is increasingly used in chest medicine in secondary care. The indications for TUS are well known but less is known about their relative frequency. The purpose of this observational study was to describe the common indications for TUS and their relative frequency and the impact of TUS on management in a consecutive group of patients.

Methods

80 consecutive inpatients and outpatients referred for TUS by the same operator in a UK National Health Service teaching hospital were included. Demographic data, clinical indication, findings and effect of TUS on clinical management were noted.

Results

The most common clinical indication was to assess a pleural effusion in 60/80 cases (75%), but other indications included assessment of diaphragmatic function, pleural thickening and chest wall masses. TUS significantly altered patient management in 52/80 cases (65%): it resolved equivocal chest radiograph (CXR) findings and excluded pathology in 20/80 cases (25%), detected effusions not visible on CXR in 14/80 cases (18%), localised a safe site for medical thoracoscopy in 11/80 cases (14%) when not clinically apparent, and detected unexpected septation in 7/80 cases (9%). TUS guided pleural cytology diagnosed pleural fluid metastases in 9/22 cases aspirated (41%).

Conclusion

There are many clinical indications for TUS but the most common is pleural effusion assessment. TUS can diagnose inoperable pleural metastases, allow safe day case pleural intervention, exclude significant pleural pathology not visible on CXR, and triage further investigation.
Tobacco Institute lobbying at the state and local levels of government in the 1990s
Authors: Morley C P , Cummings K M , Hyland A , Giovino G A , Horan J K
Published: January 2010

Objective: To describe variation in Tobacco Institute (TI) lobbying expenditures across states and test whether these expenditures vary in relationship to measures of tobacco control activity at the state level.

Independent variable: Data for this study came from the TI's State Activities Division (SAD) annual budgets for the years 1991-97, excluding 1993. These data include budgetary information pertaining to state and local lobbying activity and special projects reported by state.

Dependent variables: The following measures of state tobacco control activity during the period 1991 to 1997 were considered: (1) American Stop Smoking Intervention Study (ASSIST) funding; (2) voter initiatives to raise cigarette taxes; (3) cigarette excise tax level; (4) workplace smoking restrictions; (5) the intensification of smoke-free air laws covering private worksites, government worksites, and restaurants; (6) the intensification of strength of sales to minors laws; (7) the intensification of strength of laws that punish minors for possessing, purchasing, and/or using cigarettes; (8) state status as a major grower of tobacco; (9) partisan control of state government, 1996; and (10) an overall composite index reflecting a state's strength of tobacco control, combining cigarette prices with workplace and home smoking bans.

Results: The overall annual budget for the TI declined steadily during the 1990s, from $47.7 million in 1991 to $28.1 million by 1996. The proportion of the TI's budget allocated to the SAD remained relatively stable at about 30%. TI expenditures for lobbyists were highest in California where tobacco control activity has been strong for the past decade. We found significant associations between TI SAD expenditures and cigarette excise tax levels, the status of a state as a recipient of federal ASSIST funds, and changes in the strength of statewide laws that penalise minors for possessing, purchasing, and/or using cigarettes. We found little or no association between state and local lobbying budgets of the TI and changes in statewide smoke-free air laws, although we did find evidence of TI special project expenditures earmarked to specific states and localities to resist clean indoor air legislation/regulations (that is, Maryland and New York City). We found no significant correlation between TI lobbying expenditures and sales to minors' laws, status as a major producer of tobacco, or partisan control of state government.

Conclusions: The findings from this study support the hypothesis that in the 1990s tobacco control activities such as raising cigarette excise taxes and participation in ASSIST attracted TI resources to undermine these efforts.
The cigarette pack as image: new evidence from tobacco industry documents
Authors: Wakefield M , Morley C , Horan J K , Cummings K M
Published: January 2010

Objectives: To gain an understanding of the role of pack design in tobacco marketing.

Methods: A search of tobacco company document sites using a list of specified search terms was undertaken during November 2000 to July 2001.

Results: Documents show that, especially in the context of tighter restrictions on conventional avenues for tobacco marketing, tobacco companies view cigarette packaging as an integral component of marketing strategy and a vehicle for (a) creating significant in-store presence at the point of purchase, and (b) communicating brand image. Market testing results indicate that such imagery is so strong as to influence smoker's taste ratings of the same cigarettes when packaged differently. Documents also reveal the careful balancing act that companies have employed in using pack design and colour to communicate the impression of lower tar or milder cigarettes, while preserving perceived taste and “satisfaction”. Systematic and extensive research is carried out by tobacco companies to ensure that cigarette packaging appeals to selected target groups, including young adults and women.

Conclusions: Cigarette pack design is an important communication device for cigarette brands and acts as an advertising medium. Many smokers are misled by pack design into thinking that cigarettes may be “safer”. There is a need to consider regulation of cigarette packaging.
The structure of the female postabdomen and associated sensilla of tephritoid flies (Diptera: Tephritoidea)
Authors: Kozánek M , Belcari A
Published: January 2010

The external morphology of Tephritoidea was studied, including the types and distribution of sensilla on the female postabdomen. The complex oviposition behavior of tephritoid flies has resulted in extensive morphological modifications of the female postabdominal segments and the formation of characteristic distribution patterns of sensilla. The study revealed three morphologically distinct types of postabdomen in Tephritoidea: otitid, tephritid, and pyrgotid. The possible physiological functions of the major morphological adaptations and the homologies of segments of the post abdomen are discussed. The results confirm the present conception of the superfamily Tephritoidea, with the exception of Piophilidae. The morphological differences found in the female terminalia of Piophilidae indicate that inclusion of this family within Tephritoidea should be reconsidered.
Response to acute stress in the Harlequin Duck (Histrionicus histrionicus) during the breeding season and moult: relationships to gender, condition, and life-history stage
Authors: Perfito N , Schirato G , Brown M , Wingfield J C
Published: January 2010

Seasonal adjustments and individual responses to environmental perturbations have been well characterized in many passerine species but similar studies in other groups of birds are sparse. Larger-bodied and longer-lived avian species have different life-history strategies and different energy-storage and -utilization patterns. We investigated the response to capture stress in male and female Harlequin Ducks (Histrionicus histrionicus) during the breeding season on montane rivers and during moult on coastal waterways of Washington State. Females arrived at the breeding grounds in better condition and had a smaller rise in circulating corticosterone during 1 h of restraint than males. As the breeding season progressed, body condition declined in females and their adrenocortical response to acute stress became more pronounced. A potentially disruptive environmental condition, high river flow during the breeding season, was not associated with lower nesting success, lower body condition indices, or higher corticosterone levels (baseline or maximum concentration). The maximum corticosterone concentration reached over 1 h of restraint was negatively correlated with body condition in females during the breeding season. Lastly, males and females had similar adrenocortical responses to capture and handling during moult. We relate differential responses to acute stress between males and females to different selective pressures during the breeding season.
Synchrony in lemming and vole populations in the Canadian Arctic
Authors: Krebs Charles J , Kenney Alice J , Gilbert Scott , Danell Kjell , Angerbjörn Anders , Erlinge Sam , Bromley Robert G , Shank Chris , Carriere Suzanne
Published: January 2010

Population fluctuations may occur in synchrony among several rodent species at a given site, and they may occur in synchrony over large geographical areas. We summarize information on synchrony in lemmings and voles from the Canadian Arctic for the past 20 years. The most detailed available information is from the central Canadian Arctic, where snap-trap samples have been taken annually at several sites for periods of up to 15 years. Geographical synchrony in the same species among different sites was strong, especially for the central and eastern Canadian Arctic. Synchrony among different species at a given site was also generally high. When one species is at high density, densities of all species at that site tend to be high. These results do not easily fit the mobile-predator hypothesis proposed to explain regional synchrony, and are more consistent with the weather hypothesis, which we suggest both entrains synchrony among sites and enforces synchrony among species within a site. We tentatively support the weather hypothesis for geographical synchrony in lemmings, and recommend the establishment of a circumpolar program to monitor lemming cycles and predator movements that would advance our understanding of these large-scale patterns of cyclic synchrony.
Leadership behavior in relation to dominance and reproductive status in gray wolves,Canis lupus
Authors: Peterson Rolf O , Jacobs Amy K , Drummer Thomas D , Mech L David , Smith Douglas W
Published: January 2010

We analyzed the leadership behavior of breeding and nonbreeding gray wolves (Canis lupus) in three packs during winter in 19971999. Scent-marking, frontal leadership (time and frequency in the lead while traveling), initiation of activity, and nonfrontal leadership were recorded during 499 h of ground-based observations in Yellowstone National Park. All observed scent-marking (N = 158) was done by breeding wolves, primarily dominant individuals. Dominant breeding pairs provided most leadership, consistent with a trend in social mammals for leadership to correlate with dominance. Dominant breeding wolves led traveling packs during 64% of recorded behavior bouts (N = 591) and 71% of observed travel time (N = 64 h). During travel, breeding males and females led packs approximately equally, which probably reflects high parental investment by both breeding male and female wolves. Newly initiated behaviors (N = 104) were prompted almost 3 times more often by dominant breeders (70%) than by nonbreeders (25%). Dominant breeding females initiated pack activities almost 4 times more often than subordinate breeding females (30 vs. 8 times). Although one subordinate breeding female led more often than individual nonbreeders in one pack in one season, more commonly this was not the case. In 12 cases breeding wolves exhibited nonfrontal leadership. Among subordinate wolves, leadership behavior was observed in subordinate breeding females and other individuals just prior to their dispersal from natal packs. Subordinate wolves were more often found leading packs that were large and contained many subordinate adults.
Ultrastructure of spermatogenesis in the free-living marine nematodePontonema vulgare(Enoplida, Oncholaimidae)
Authors: Yushin Vladimir V , Coomans August , Malakhov Vladimir V
Published: January 2010

Spermatogenesis in testes of the free-living marine nematode Pontonema vulgare was studied with electron microscopy. The nucleus of spermatocytes has a large nucleolus; the cytoplasm is filled with numerous ribosomes, mitochondria, cisternae of the rough endoplasmic reticulum (RER), Golgi bodies, and flattened osmiophilic cisternae, which are interpreted as the modified membranous organelles (MO) of the spermatozoa of other nematodes studied. After completion of the second meiotic telophase, the nucleus is surrounded by a newly formed nuclear envelope. Further nucleus transformation includes condensation of the chromatin and shrinkage of the nuclear envelope. The deep infoldings of the nuclear envelope give a starlike shape to the nuclei. The cytoplasm of the early spermatids contains the same organelles as in the late spermatocytes, including MO. Many of the latter assume a cuplike or pocketlike shape. During spermatogenesis the peripheral cytoplasm containing the ribosomes, RER, Golgi bodies, and transparent vesicles moves to one pole of the cell forming the residual body. The main cell body of the late spermatid includes the nucleus, mitochondria, and MO embedded in a dense filamentous matrix. The fibrous bodies (FB) of a paracrystalline structure occur in spermatids throughout their developmental transformations. The central part of the spermatozoa contains a starlike nucleus with a nuclear envelope. The filamentous cytoplasm of the spermatozoa includes mitochondria and MO. The spermatozoa extracted from the testes form numerous long filopodia. The dense filamentous cytoplasm of the spermatozoa is continuous with the content of the filipodia. The reconstitution of the nuclear envelope and separate development of MO and FB described in P. vulgare spermatogenesis are the special characters of enoplid nematodes. The reduced character of FB development and simplified structure of MO differentiate P. vulgare from other nematodes studied.
Genome size estimates for some oligochaete annelids
Authors: Gregory T Ryan , Hebert Paul D.N
Published: January 2010

Haploid genome sizes (C-values) were estimated for 12 species of freshwater oligochaetes (families Naididae and Tubificidae) and 15 species of earthworms (families Lumbricidae and Megascolecidae). Aquatic worms ranged in genome size from about 0.8 to 7.6 pg, while earthworms varied from approximately 0.4 to 1.2 pg. Interspecific differences in nuclear DNA content did not appear to be linked to variation in chromosome number, but there was evidence of cryptopolyploidy in the aquatic worms. No correlations were found between genome size and either body size or life-history traits, although there may be an association between higher DNA content and parthenogenetic reproduction in earthworms.
Into thin air: vertical migration, body condition, and quality of terrestrial habitats of alpine common toads, Bufo bufo
Authors: Sztatecsny M , Schabetsberger R
Published: January 2010

Since the end of the 1980s there has been increasing evidence of worldwide amphibian declines in high-altitude regions. Moreover, amphibian conservation has so far mostly neglected the terrestrial habitat, which is essential for effective protection measures. We determined the location and quality of terrestrial habitats of common toads (Bufo bufo L., 1758) in a naturally fragmented alpine environment (Schlumsee, 1105 m a.s.l., Northern Calcareous Alps, Austria) characterized by a high diversity of available microhabitats. By radio-tracking 18 individuals during their post-spawning migration, we located terrestrial habitats 1301000 m horizontally away from and 85390 m above the breeding site. This is the first study to show vertical migration over several hundred metres in adult amphibians. Both adult and juvenile toads completed the migration within 27 weeks and, on their way to the summer habitat, climbed 45° scree slopes and ascended cliffs with slopes of up to 65°. Body condition indices were highest for individuals originating from the terrestrial summer habitat at the highest elevation, which is characterized by the highest vegetation diversity, a high abundance of food, and the highest insolation, probably allowing the toads to extend their activity period for food intake. Our study suggests that under demanding climatic conditions it can pay off for toads to undertake costly migrations to reach high-quality habitats. For amphibian conservation, high-value habitat patches need to be located and investigated to increase the effectiveness of protection measures.
Does altering patch number and connectivity change the predatory functional response type? Experiments and simulations in an acarine predator–prey system
Authors: Lester P J , Yee J M , Yee S , Haywood J , Thistlewood H MA , Harmsen R
Published: January 2010

In multipatch landscapes, understanding the role of patch number and connectivity is key for the conservation of species under processes such as predation. The functional response is the most basic form of the predatorprey interaction. Two common response types exist: a decelerating curvilinear increase in prey consumption with prey density to a plateau (type II) and a sigmoidal-shaped curve (type III). Type II responses have been observed for a variety of predators, though only type III responses allow long-term persistence and are demographically stabilizing. We tested the hypothesis that the functional response type can change from a type II to a type III with increasing patch number and (or) decreasing connectivity. The predatory mite Amblyseius fallacis (Garman, 1948) has previously been shown to have a type II response when feeding on Panonychus ulmi (Koch, 1839). We examined this predatorprey interaction using experiments that varied in patch number, and simulations that varied in both patch number and connectivity. In no experimental or simulation trial did altering patch number or connectivity change the predator's functional response from type II to type III, even with an 80-fold decrease in patch connectivity. How do predators with this demographically destabilizing functional response persist? Hypotheses regarding metapopulations and alternative prey are discussed.
Linking climate and physiology at the population level for a key life-history stage of turtles
Authors: Willette Demian A.S , Tucker John K , Janzen Fredric J
Published: January 2010

Forthcoming climate change is expected to impact the global biota, particularly by altering range limits. However, the roles of early life stages in affecting biogeography and the impact of climate change on reptiles are both poorly understood. Fitness of neonatal reptiles depends greatly on energy reserves and body size, which themselves are affected by abiotic conditions in laboratory experiments performed during embryonic development and posthatching dormancy. To test whether these relationships between environment and physiology hold in nature, we conducted a 6-year field study on a natural northern population of red-eared slider turtles, Trachemys scripta elegans (Wied-Neuwied, 1839). Climatic conditions varied substantially and impacted offspring phenotypes. Consistent with bioenergetic predictions, cohorts that experienced warmer periods of posthatching dormancy had less dry residual yolk mass than similar-sized hatchlings that experienced cooler overwintering periods. Thus, global warming may exert adverse effects on turtle energy reserves important to fitness during crucial early life stages; this negative physiological impact may extend to other ectotherms with obligate, nonfeeding stages.
Vocal repertoire and acoustic behavior of the isolated AT1 killer whale subpopulation in southern Alaska
Authors: Saulitis Eva L , Matkin Craig O , Fay Francis H
Published: January 2010

Killer whales, Orcinus orca (L., 1758), in the North Pacific are classified as three genetically distinct ecotypes: residents (fish-eaters), transients (mammal-eaters), and offshores (probable fish-eaters). Within the transient ecotype, three putative subpopulations have been identified by genetic analysis: West Coast transients, Gulf of Alaska transients, and AT1 transients. Here, we examine the behavior and vocalizations of the AT1 transients, which are found only in the Prince William Sound/Kenai Fjords region, to determine if their acoustic behavior distinguishes them from other genetically distinct transient subpopulations. We identified 14 discrete, pulsed calls in the vocal repertoire of the AT1 transients. These calls were entirely different than those of West Coast and sympatric Gulf of Alaska transients. Despite their large call repertoire, AT1 transients were silent most of the time, utilizing a foraging strategy of stealth, acoustic crypsis, and passive listening for locating marine-mammal prey. Unlike resident killer whales, AT1 transient vocalization types were context specific. For example, lone AT1 transients produced long-distance, high-amplitude pulsed calls in stereotyped sequences to locate other AT1 whales. In contrast, hunting individuals emitted low-amplitude pulsed calls to maintain contact with group members. The repertoire and call-usage patterns of the AT1 transients are consistent with genetic evidence that they are a unique, reproductively and socially isolated subpopulation in danger of extinction.
FAILURE MECHANISM AND ITS CONTROL OF BUILDING STRUCTURES UNDER EARTHQUAKES BASED ON STRUCTURAL SYSTEM CONCEPT
Authors: YE LIEPING , QU ZHE
Published: January 2010

By taking building structures as systems, the difference between the safety margins of a structure and that of its element is clarified and the robustness of the structure to resist unexpected disasters is discussed. The system concept is further used to introduce the concepts of importance levels and functionality levels in structural systems, the designability of structural systems is then pointed out. The local and global failure mechanisms of building structures under earthquake are summarized, and the failure mechanism control method is discussed based on the concepts of system and designability. For global failure mechanism, the desirable seismic performance is put forward, and at last some practical methods to control the seismic failure mechanism and the failure procedures are proposed based on the hierarchy concept of the structural system.
EFFECTS OF EARTHQUAKE EARLY WARNING TO EXPRESSWAY DRIVERS BASED ON DRIVING SIMULATOR EXPERIMENTS
Authors: MARUYAMA YOSHIHISA , SAKAYA MASATO , YAMAZAKI FUMIO
Published: January 2010

To reduce casualties and troubles due to earthquakes, Japan Meteorological Agency introduced earthquake early warning (EEW) to general public on 1 October 2007. However, the possibility that EEW induces traffic accidents exists because EEW through car radio may not be transmitted to all the expressway drivers. Hence, the effects of EEW were investigated based on driving simulator experiments. Two kinds of experiments were performed in this study. First, single driving simulator was employed to reveal the effects of EEW on expressways. The reactions of drivers with/without warning are compared in avoiding an obstacle induced by seismic motion. Second, three synchronized driving simulators, simulating three cars running together on an expressway, were employed. When EEW was transmitted to only one car, some drivers reduced speed suddenly, and accidents occurred in two cases out of 14 tests. These experiments show the necessity of public education how to react an EEW on expressways. Turning on the hazard lights after receiving an EEW and then reducing speed gradually is suggested to avoid traffic accidents.
UNIFIED COMPRESSIVE STRENGTH MODEL OF CONFINED CONCRETE
Authors: NIU DITAO , YU FENG
Published: January 2010

The bearing capacity and ductility of confined concrete can be greatly increased by the confinement of confining material. To better study the mechanical behavior of confined concrete, this paper presents the yield criterion of confined concrete, based on the static equilibrium condition, the unified compressive strength model of confined concrete is established. The model captures the character of confined concrete, the effects of confinement effect ratio, the compressive strength of unconfined concrete, and the mechanical properties of confining material on the compressive strength of confined concrete were carefully analyzed.
Factor in the neighbors
Authors: Koren Yehuda
Published: January 2010

Recommender systems provide users with personalized suggestions for products or services. These systems often rely on collaborating filtering (CF), where past transactions are analyzed in order to establish connections between users and products. The most common approach to CF is based on neighborhood models, which originate from similarities between products or users. In this work we introduce a new neighborhood model with an improved prediction accuracy. Unlike previous approaches that are based on heuristic similarities, we model neighborhood relations by minimizing a global cost function. Further accuracy improvements are achieved by extending the model to exploit both explicit and implicit feedback by the users. Past models were limited by the need to compute all pairwise similarities between items or users, which grow quadratically with input size. In particular, this limitation vastly complicates adopting user similarity models, due to the typical large number of users. Our new model solves these limitations by factoring the neighborhood model, thus making both item-item and user-user implementations scale linearly with the size of the data. The methods are tested on the Netflix data, with encouraging results.
Self-sufficient itemsets
Authors: Webb Geoffrey I.
Published: January 2010

Self-sufficient itemsets are those whose frequency cannot be explained solely by the frequency of either their subsets or of their supersets. We argue that itemsets that are not self-sufficient will often be of little interest to the data analyst, as their frequency should be expected once that of the itemsets on which their frequency depends is known. We present tests for statistically sound discovery of self-sufficient itemsets, and computational techniques that allow those tests to be applied as a post-processing step for any itemset discovery algorithm. We also present a measure for assessing the degree of potential interest in an itemset that complements these statistical measures.
Mining multidimensional and multilevel sequential patterns
Authors: Plantevit Marc , Laurent Anne , Laurent Dominique , Teisseire Maguelonne , Choong Yeow WEI
Published: January 2010

Multidimensional databases have been designed to provide decision makers with the necessary tools to help them understand their data. This framework is different from transactional data as the datasets contain huge volumes of historicized and aggregated data defined over a set of dimensions that can be arranged through multiple levels of granularities. Many tools have been proposed to query the data and navigate through the levels of granularity. However, automatic tools are still missing to mine this type of data in order to discover regular specific patterns. In this article, we present a method for mining sequential patterns from multidimensional databases, at the same time taking advantage of the different dimensions and levels of granularity, which is original compared to existing work. The necessary definitions and algorithms are extended from regular sequential patterns to this particular case. Experiments are reported, showing the significance of this approach.
Volume composition and evaluation using eye-tracking data
Authors: Lu Aidong , Maciejewski Ross , Ebert David S.
Published: January 2010

This article presents a method for automating rendering parameter selection to simplify tedious user interaction and improve the usability of visualization systems. Our approach acquires the important/interesting regions of a dataset through simple user interaction with an eye tracker. Based on this importance information, we automatically compute reasonable rendering parameters using a set of heuristic rules, which are adapted from visualization experience and psychophysical experiments. A user study has been conducted to evaluate these rendering parameters, and while the parameter selections for a specific visualization result are subjective, our approach provides good preliminary results for general users while allowing additional control adjustment. Furthermore, our system improves the interactivity of a visualization system by significantly reducing the required amount of parameter selections and providing good initial rendering parameters for newly acquired datasets of similar types.
Computational visual attention systems and their cognitive foundations
Authors: Frintrop Simone , Rome Erich , Christensen Henrik I.
Published: January 2010

Based on concepts of the human visual system, computational visual attention systems aim to detect regions of interest in images. Psychologists, neurobiologists, and computer scientists have investigated visual attention thoroughly during the last decades and profited considerably from each other. However, the interdisciplinarity of the topic holds not only benefits but also difficulties: Concepts of other fields are usually hard to access due to differences in vocabulary and lack of knowledge of the relevant literature. This article aims to bridge this gap and bring together concepts and ideas from the different research areas. It provides an extensive survey of the grounding psychological and biological research on visual attention as well as the current state of the art of computational systems. Furthermore, it presents a broad range of applications of computational attention systems in fields like computer vision, cognitive systems, and mobile robotics. We conclude with a discussion on the limitations and open questions in the field.