bluuebunny/crossref_metadata_2025 huggingface dataset:
A review of combined power and cooling cycles
Authors: Demirkaya Gökmen , Padilla Ricardo Vasquez , Goswami D. Yogi
Published: February 2013

Combined power and refrigeration cycles have been explored for improving their overall energy conversion efficiency and decreasing the cost of energy produced. Bottoming cycles can be used to recover the waste heat or exhaust heat of gas turbines and conventional steam Rankine cycles and convert it to work and/or refrigeration. In most applications, refrigeration is the more expensive product than power because it requires refrigeration equipment as well as power to produce conventional refrigeration. Therefore, the additional output of refrigeration by the combined cycle provides greater benefit than conventional power systems. This paper presents a review of combined power and cooling cycles for effective utilization of heat sources.

This article is categorized under:

Concentrating Solar Power > Science and Materials

Energy Efficiency > Science and Materials

Energy Systems Economics > Science and Materials
Laparoscopic left lateral sectionectomy as a training procedure for surgeons learning laparoscopic hepatectomy
Authors: Hasegawa Yasushi , Nitta Hiroyuki , Sasaki Akira , Takahara Takeshi , Ito Naoko , Fujita Tomohiro , Kanno Shoji , Nishizuka Satoshi , Wakabayashi Go
Published: February 2013

Background

Laparoscopic liver resection remains limited to a relatively small number of institutions because of insufficient hepatic and laparoscopic surgical experience and few training opportunities. The aim of this study was to assess the feasibility and safety of an improved laparoscopic left lateral sectionectomy technique as a training procedure for new surgeons.

Methods

Twenty‐four laparoscopic left lateral sectionectomies (LLLSs) were retrospectively reviewed. Patients were divided into 3 groups with 8 patients in each: those undergoing surgery by expert surgeons prior to 2008 (Group A); those undergoing surgery by expert surgeons after 2008, when a standardized LLLS technique was adopted (Group B); and those undergoing LLLS by junior surgeons being trained (Group C).

Results

The median operative time was significantly shorter for Group B (103 min; range, 99—109 min) and C (107 min; range, 85—135 min) patients than for Group A (153 min; range, 95—210 min) patients. There were no significant differences in blood loss or hospital stay. In Groups B and C, no conversions to open laparotomy or complications occurred.

Conclusion

The standardized LLLS procedure was both safe and feasible as a technique for training surgeons in laparoscopic hepatectomy.
Thermally mediated body temperature, water content and aggregation behaviour in the intertidal gastropodNerita atramentosa
Authors: Chapperon Coraline , Le Bris Cédric , Seuront Laurent
Published: February 2013

Intertidal organisms are vulnerable to global warming as they already live at, or near to, the upper limit of their thermal tolerance window. The behaviour of ectotherms could, however, dampen their limited physiological abilities to respond to climate change (e.g. drier and warmer environmental conditions) which could substantially increase their survival rates. The behaviour of ectotherms is still mostly overlooked in climate change studies. Here, we investigate the potential of aggregation behaviour to compensate for climate change in an intertidal gastropod species (Nerita atramentosa) in South Australia. We used thermal imaging to investigate (1) the heterogeneity in individual snail water content and body temperature and surrounding substratum temperature on two topographically different habitats (i.e. rock platform and boulders) separated by 250 m at both day‐ and night‐times, (2) the potential relationship between environment temperature (air and substratum) and snail water content and body temperature, and (3) the potential buffering effect of aggregation behaviour on snail water content and body temperature. Both substratum and snail temperature were more heterogeneous at small spatial scales (a few centimetres to a few metres) than between habitats. This reinforces the evidence that mobile intertidal ectotherms could survive locally under warmer conditions if they can locate and move behaviourally in local thermal refuges.N. atramentosabehaviour, water content and body temperature during emersion seem to be related to the thermal stability and local conditions of the habitat occupied. Aggregation behaviour reduces both desiccation and heat stresses but only on the boulder field. Further investigations are required to identify the different behavioural strategies used by ectothermic species to adapt to heat and dehydrating conditions at the habitat level. Ultimately, this information constitutes a fundamental prerequisite to implement conservation management plans for ectothermic species identified as vulnerable in the warming climate.
Modelling Dyadic Interaction with Hawkes Processes
Authors: Halpin Peter F. , De Boeck Paul
Published: February 2013

We apply the Hawkes process to the analysis of dyadic interaction. The Hawkes process is applicable to excitatory interactions, wherein the actions of each individual increase the probability of further actions in the near future. We consider the representation of the Hawkes process both as a conditional intensity function and as a cluster Poisson process. The former treats the probability of an action in continuous time via non-stationary distributions with arbitrarily long historical dependency, while the latter is conducive to maximum likelihood estimation using the EM algorithm. We first outline the interpretation of the Hawkes process in the dyadic context, and then illustrate its application with an example concerning email transactions in the work place.
Challenges for mesoscale climatology execution on experimental grid computing systems
Authors: Almeida Eugenio Sper de , Campos Velho Haroldo Fraga de , Preto Airam Jonatas
Published: February 2013

This paper discusses the challenges of executing a long-term application on a computational grid, which generates the climatology of the atmospheric numerical model BRAMS (Brazilian development on Regional Atmospheric Modeling System) using ensemble members. We have developed a workflow that submits climatology to the computational grid composed by three different grid middlewares (OurGrid, OAR/CiGri and Globus) and three clusters (situated in Porto Alegre, São José dos Campos and Cachoeira Paulista—Brazil). The application characteristics demand a processing grid, rather than a data grid, due to intensive computation and data transfer between the geographically distributed grid nodes. We achieved the goal of generating the climatology using a computational grid. However, we observed problems on application performance due data transfer and non-availability of the computational grid. Questions related to data storage/transfer and grid failures must be better treated to ensure application performance.
Rebuilding cancer metastasis in the mouse
Authors: Saxena Meera , Christofori Gerhard
Published: February 2013

Most cancer deaths are due to the systemic dissemination of cancer cells and the formation of secondary tumors (metastasis) in distant organs. Recent years have brought impressive progress in metastasis research, yet we still lack sufficient insights into how cancer cells migrate out of primary tumors and invade into neighboring tissue, intravasate into the blood or the lymphatic circulation, survive in the blood stream, and target specific organs to initiate metastatic outgrowth. While a large number of cellular and animal models of cancer have been crucial in delineating the molecular mechanisms underlying tumor initiation and progression, experimental models that faithfully recapitulate the multiple stages of metastatic disease are still scarce. The advent of sophisticated genetic engineering in mice, in particular the ability to manipulate gene expression in specific tissue and at desired time points at will, have allowed to rebuild the metastatic process in mice. Here, we describe a selection of cellular experimental systems, tumor transplantation mouse models and genetically engineered mouse models that are used for monitoring specific processes involved in metastasis, such as cell migration and invasion, and for investigating the full metastatic process. Such models not only aid in deciphering the pathomechanisms of metastasis, but are also instrumental for the preclinical testing of anti‐metastatic therapies and further refinement and generation of improved models.
Whole transcriptome analysis of the ERα synthetic fragment P295‐T311 (ERα17p) identifies specific ERα‐isoform (ERα, ERα36)‐dependent and ‐independent actions in breast cancer cells
Authors: Notas George , Kampa Marilena , Pelekanou Vassiliki , Troullinaki Maria , Jacquot Yves , Leclercq Guy , Castanas Elias
Published: February 2013

ERα17p is a peptide corresponding to the sequence P295LMIKRSKKNSLALSLT311 of the estrogen receptor alpha (ERα) and initially found to interfere with ERα‐related calmodulin binding. ERα17p was subsequently found to elicit estrogenic responses in E2‐deprived ERα‐positive breast cancer cells, increasing proliferation and ERE‐dependent gene transcription. Surprisingly, in E2‐supplemented media, ERα17p‐induced apoptosis and modified the actin network, influencing cell motility. Here, we report that ERα17p internalizes in breast cancer cells (T47D, MDA‐MB‐231, SKBR3) and induces a massive early (3 h) transcriptional activity. Remarkably, about 75% of significantly modified transcripts were also modified by E2, confirming the pro‐estrogenic profile of ERα17p. The different ER spectra of the used cell lines allowed us to identify a specific ERα17p signature related to ERα as well as its variant ERα36. With respect to ERα, the peptide activates nuclear (cell cycle, cell proliferation, nucleic acid and protein synthesis) and extranuclear signaling pathways. In contrast, through ERα36, it mainly triggers inhibitory actions on inflammation. This is the first work reporting a detailed ERα36‐specific transcriptional signature. In addition, we report that ERα17p‐induced transcripts related to apoptosis and actin modifying effects of the peptide are independent from its estrogen receptor(s)‐related actions. We discuss our findings in view of the potential use of ERα17p as a selective peptidomimetic estrogen receptor modulator (PERM).
Do statistical segmentation abilities predict lexical-phonological and lexical-semantic abilities in children with and without SLI?
Authors: MAINELA-ARNOLD ELINA , EVANS JULIA L.
Published: February 2013

This study tested the predictions of the procedural deficit hypothesis by investigating the relationship between sequential statistical learning and two aspects of lexical ability, lexical-phonological and lexical-semantic, in children with and without specific language impairment (SLI). Participants included forty children (ages 8;5–12;3), twenty children with SLI and twenty with typical development. Children completed Saffran's statistical word segmentation task, a lexical-phonological access task (gating task), and a word definition task. Poor statistical learners were also poor at managing lexical-phonological competition during the gating task. However, statistical learning was not a significant predictor of semantic richness in word definitions. The ability to track statistical sequential regularities may be important for learning the inherently sequential structure of lexical-phonological, but not as important for learning lexical-semantic knowledge. Consistent with the procedural/declarative memory distinction, the brain networks associated with the two types of lexical learning are likely to have different learning properties.
Population dynamics with age-dependent diffusion and death rates
Authors: AL-JARARHA M. , OU CHUNHUA
Published: February 2013

In this paper we investigate the population dynamics of a species with age structure in the case where the diffusion and death rates of the matured population are both age-dependent. We develop a new application of the age-structure technique in terms of an integral equation. For unbounded spatial domains, we study the existence of travelling waves, whilst in bounded domains, we investigate the existence of positive steady-state solutions and their stability.
Indices of Cognitive Dysfunction in Relapsing-Remitting Multiple Sclerosis: Intra-individual Variability, Processing Speed, and Attention Network Efficiency
Authors: Wojtowicz Magdalena , Omisade Antonina , Fisk John D.
Published: February 2013

Impairments in attention and information processing speed are common in multiple sclerosis (MS) and may contribute to impairments of other cognitive abilities. This study examined attentional efficiency, information processing speed and intra-individual variability in response speed using the Attention Network Test-Interactions (ANT-I) in mildy-affected patients with MS. Thirty-one patients with relapsing-remitting MS and 30 age, sex, and education-matched controls completed the ANT-I, as well as the Paced Auditory Serial Attention Test (PASAT), as a standard clinical measure of information processing efficiency. As expected, patients with MS were slower in reaction time performance on the ANT-I and had poorer performance on the PASAT compared to controls. Patients with MS also demonstrated poorer efficiency in their executive control of attention on the ANT-I, suggesting difficulties with top-down allocation of attention. In addition, the MS group demonstrated greater intra-individual variability in the responses to the ANT-I even when their slower overall response time and other factors such as practice were accounted for. Intra-individual variability was found to best predict group membership compared to PASAT scores and other ANT-I scores. These results suggest that intra-individual variability may provide sensitive, unique and important information regarding cognitive functioning in early MS. (JINS, 2013, 19, 1–8)
Introduction: Risk, Social Inclusion and the Life Course
Authors: Zinn Jens O.
Published: February 2013

In social policy debates and research over recent years, ‘risk’, ‘social inclusion’ and ‘the life course’ have become influential topics. In this themed section we will revisit these concepts and analyse how they have influenced policy debates and research in Australia and elsewhere. The contributions were developed as part of a research collaboration that brings together expertise from social policy, gender studies, risk sociology, social work, youth studies and research on ageing and old age. This introduction outlines the concepts and dimensions we found helpful for analysing social policy practice and research and the key arguments of the contributions.
Exploring Regimes in Black Hole Scaling
Authors: Heinz Sebastian , Merloni Andrea
Published: February 2013

Recent observational evidence suggests the existence of two tracks in the radio-X-ray relation for X-ray binaries. Claims have also been made for deviations from the so-called fundamental plane of black hole activity due to the influence of radiative cooling on synchrotron emission from jets and the relative importance of disk and jet emission. In addition, cases of strongly boosted classes of objects, such as BL Lacs, show evidence for jet emission in their location relative to the fundamental plane. In light of the recent literature activity discussing these issues, we revisit the scaling relations expected for synchrotron emission from jet cores. We review the set of scaling laws expected for different types of emission and discuss their relevance to the new observational data, and the conditions under which breaks in the observed scaling relations should be expected. None of the canonical cases offer a satisfactory explanation for the best fit slope of the steep branch of the radio-X-ray relation in hard-state X-ray binaries.
LOFT: the Large Observatory For X-ray Timing
Authors: Belloni Tomaso M. , Bozzo Enrico ,   (on behalf of the LOFT Consortium)
Published: February 2013

LOFT, the large observatory for X-ray timing, is a new mission concept competing with other four candidates for a launch opportunity in 2022-2024. LOFT will be performing high-time resolution X-ray observations of compact objects, combining for the first time an unprecedented large collecting area for X-ray photons and a spectral resolution approaching that of CCD-based X-ray instruments (down to 200 eV FWHM at 6 keV). The operating energy range is 2-80 keV. The main science goals of LOFT are the measurement of the neutron stars equation of states and the test of General Relativity in the strong field regime. The breakthrough capabilities of the instruments on-board LOFT will permit to open also new discovery windows for a wide range of Galactic and extragalactic X-ray sources.

In this contribution, we provide a general description of the mission concept and summarize its main scientific capabilities.
High-mass X-ray binaries in a cosmological context
Authors: Artale María Celeste , Pellizza Leonardo J. , Tissera Patricia B. , Mirabel I. Felix
Published: February 2013

Recent observational and theoretical results suggest that the production rates and luminosities of high-mass X-ray binaries depend on metallicity. To test this prediction, we combine HMXB population synthesis results with numerical simulations of galaxy formation to produce synthetic populations of HMXBs in star-forming galaxies, and compare the model predictions to observations of HMXB populations in nearby and high-redshift galaxies. Our models show a fair agreement with observations only when the HMXB production and luminosities are assumed to depend strongly on metallicity.
Hα photometry of low mass stars in 47 Tucanae: chromospheric activity and exotica
Authors: Beccari Giacomo , De Marchi Guido , Panagia Nino , Pasquini Luca
Published: February 2013

We have used archival Hubble Space Telescope (HST) observations obtained with the Advanced Camera for Surveys (ACS) to study the Hα emission properties of main sequence (MS) stars in the globular cluster 47 Tucanae. An accurate photometric measurement of their Hα equivalent width, allows us to identify objects with large Hα emission. We demonstrate that this method allows us to identify and characterise candidate cataclysmic variables (CVs) with high efficiency, reconciling observations with theoretical predictions on the number of dynamically formed CVs expected in a 47 Tucanae-like globular cluster.
Fast co-evolving behavior of the corona with type-I X-ray bursts in Aql X-1
Authors: Chen Yu-Peng , Zhang Shu
Published: February 2013

Taking advantage of the type-I X-ray bursts from the hard surface of a NS of the NS XRB Aql X-1 to probe the purported corona, we found, during the bursts, a clear anti-correlation between the soft and the hard X-rays, which indicates an additional cooling of the corona with the soft X-ray shower fed by the bursts. The phenomenon was also found in IGR J17473-2721, 4U 1636-536 and 4U 1608-522. The time delay between the burst emission and corona emission are different each other, but the time delay are all within 5 seconds. The similarity and difference may be understood that the corona have same mechanism but behave different structure or scale.
Determining the neutron star surface magnetic field strength of two Z sources
Authors: Ding Guoqiang , Huang Chunping , Wang Yanan
Published: February 2013

From the extreme position of disk motion, we infer the neutron star (NS) surface magnetic field strength (B0) of Z-source GX 17+2 and Cyg X-2. The inferred B0 of GX 17+2 and Cyg X-2 are ~(1–5)×108 G and ~(1–3)×108 G, respectively, which are not inferior to that of millisecond X-ray pulsars or atoll sources. It is likely that the NS magnetic axis of Z sources is parallel to the axis of rotation, which could result in the lack of pulsations in these sources.
Confronting the Models of 3 : 2 QPOs with the Evidence of Near Extreme Kerr Black Hole
Authors: Kotrlová Andrea , Török Gabriel , Šrámková Eva , Stuchlík Zdeněk
Published: February 2013

The black hole mass and spin estimates assuming various specific models of the 3 : 2 high frequency quasi-periodic oscillations (HF QPOs) have been carried out in Török et al. (2005, 2011). Here we briefly summarize some current points. Spectral fitting of the spin a ≡ cJ/GM2 in the microquasar GRS 1915 + 105 reveals that this system can contain a near extreme rotating black hole (e.g., McClintock et al., 2011). Confirming the high value of the spin would have significant consequences for the theory of the HF QPOs. The estimate of a > 0.9 is almost inconsistent with the relativistic precession (RP), tidal disruption (TD), and the warped disc (WD) model. The epicyclic resonance (Ep) and discoseismic models assuming the c- and g- modes are instead favoured. However, consideration of all three microquasars that display the 3 : 2 HF QPOs leads to a serious puzzle because the differences in the individual spins, such as a = 0.9 compared to a = 0.7, represent a generic problem almost for any unified orbital 3:2 QPO model.
Clumped stellar winds in supergiant high-mass X-ray binaries
Authors: Oskinova L. M. , Feldmeier A. , Kretschmar P.
Published: February 2013

The clumping of massive star winds is an established paradigm, which is confirmed by multiple lines of evidence and is supported by stellar wind theory. We use the results from time-dependent hydrodynamical models of the instability in the line-driven wind of a massive supergiant star to derive the time-dependent accretion rate on to a compact object in the Bondi-Hoyle-Lyttleton approximation. The strong density and velocity fluctuations in the wind result in strong variability of the synthetic X-ray light curves. Photoionization of inhomogeneous winds is different from the photoinization of smooth winds. The degree of ionization is affected by the wind clumping. The wind clumping must also be taken into account when comparing the observed and model spectra of the photoionized stellar wind.
Spectral Line Variations of Symbiotic Stars EG And, AG Dra, and BX Mon and Its Interpretation
Authors: Yoon Tae Seog , Kim Soo Hyun , Moon Hyeonwoo , Kim Kyu-Seob , Oh Hyungil
Published: February 2013

We present some results obtained by high resolution spectroscopic observations for symbiotic stars EG And, AG Dra, and BX Mon in recent years which were performed with 1.8-m reflector and echelle spectrograph BOES at Bohyunsan Optical Astronomy Observatory, Youngcheon, South Korea. The variations of Hα emission line during a night and the variations of H Balmer lines and He I emission lines among several analyzed lines over months and years are shown and discussed.
Tiefenpsychologisch fundierte Psychotherapie bei Kindern und Jugendlichen
Authors: Krischer Maya K. , Trautmann-Voigt Sabine , Kaspers Sarah , Voigt Bernd , Flechtner Hans-Henning , Lehmkuhl Gerd
Published: February 2013

Fragestellung: Die Wirksamkeit tiefenpsychologisch fundierter Psychotherapie (TP) bei Kindern und Jugendlichen ist in Deutschland noch immer unzureichend beforscht. Da die TP neben anderen Zielen sowohl kurz-, als auch langfristig eine Symptomverbesserung anstrebt, werden in der vorliegenden Arbeit Ergebnisse zur Frage der Verbesserung von Symptomen und Problemverhalten nach Ablauf von 25 Stunden ambulanter tiefenpsychologisch fundierter Kinder- und Jugendlichenpsychotherapie in der Routinepraxis vorgestellt. Zudem sollte deskriptiv die Frage aufgeworfen werden, ob im selben Zeitraum bereits eine positive Veränderung der kindlichen Lebensqualität eintritt. Methodik: Dreißig Kinder mit emotionalen-, Verhaltens- und Anpassungsstörungen, die 25 Stunden tiefenpsychologisch fundierter Psychotherapie erhielten, wurden in die Studie eingeschlossen. Das Elternurteil in der Child Behavior Checklist (CBCL) sowie das Eltern- und Therapeutenurteil im Diagnosesystem zur Erfassung psychischer Störungen im Kindes- und Jugendalter (DISYPS-KJ) wurde vor und nach 25 Stunden TP miteinander verglichen. Ergebnisse: Dieser Vergleich brachte signifikante Verbesserungen in fast allen der gemessenen CBCL-Skalen, nicht hingegen in den durch das DISYPS-KJ gemessenen Störungsbereichen. Wir fanden überwiegend mittlere Effekte. Die von den Eltern wahrgenommene allgemeine kindliche Lebensqualität verbesserte sich im Verlauf der 25 Stunden Psychotherapie nicht. Schlussfolgerungen: Die Resultate können als Hinweis auf eine wirksame Verbesserung kindlicher emotionaler und Verhaltensauffälligkeiten aus der Elternperspektive mittels 25 Stunden tiefenpsychologisch fundierter Psychotherapie verstanden werden. Allerdings erschien der gemessene Zeitraum zu kurz für eine positive Veränderung spezifischer Störungsbereiche gemäß Eltern- und Therapeutenurteil.
Using the Depression Anxiety Stress Scale 21 (DASS‐21) across cultures
Authors: Oei Tian P. S. , Sawang Sukanlaya , Goh Yong Wah , Mukhtar Firdaus
Published: February 2013

The DASS‐21 is a well‐established instrument for measuring depression, anxiety, and stress with good reliability and validity reported from Hispanic American, British, and Australian adults. However, the lack of appropriate validation among Asian populations continues to pose concerns over the use of DASS‐21 in Asian samples. Cultural variation may influence the individual's experience and emotional expression. Thus, when researchers and practitioners employ Western‐based assessments with Asian populations by directly translating them without an appropriate validation, the process can be challenging. We conducted a series of rigorous statistical tests and minimized any potential confounds from the demographic information. Following factor analyses, we performed multigroup analysis across six nations to demonstrate consistency of our findings. The advantages of this revised DASS‐18 stress scale are twofold. First, it possesses fewer items, which results in a cleaner factorial structure. Second, it has a smaller interfactor correlation. With these justifications, the revised DASS‐18 stress scale is potentially more suitable for Asian populations. Nonetheless, given limitations, findings should be considered preliminary.
Regulation of mRNA export by the PI3 kinase/AKT signal transduction pathway
Authors: Quaresma Alexandre Jose Christino , Sievert Rachel , Nickerson Jeffrey A.
Published: February 2013

UAP56, ALY/REF, and NXF1 are mRNA export factors that sequentially bind at the 5′ end of a nuclear mRNA but are also reported to associate with the exon junction complex (EJC). To screen for signal transduction pathways regulating mRNA export complex assembly, we used fluorescence recovery after photobleaching to measure the binding of mRNA export and EJC core proteins in nuclear complexes. The fraction of UAP56, ALY/REF, and NXF1 tightly bound in complexes was reduced by drug inhibition of the phosphatidylinositide 3-kinase (PI3 kinase)/AKT pathway, as was the tightly bound fraction of the core EJC proteins eIF4A3, MAGOH, and Y14. Inhibition of the mTOR mTORC1 pathway decreased the tight binding of MAGOH. Inhibition of the PI3 kinase/AKT pathway increased the export of poly(A) RNA and of a subset of candidate mRNAs. A similar effect of PI3 kinase/AKT inhibition was observed for mRNAs from both intron-containing and intronless histone genes. However, the nuclear export of mRNAs coding for proteins targeted to the endoplasmic reticulum or to mitochondria was not affected by the PI3 kinase/AKT pathway. These results show that the active PI3 kinase/AKT pathway can regulate mRNA export and promote the nuclear retention of some mRNAs.
The N-DRC forms a conserved biochemical complex that maintains outer doublet alignment and limits microtubule sliding in motile axonemes
Authors: Bower Raqual , Tritschler Douglas , VanderWaal Kristyn , Perrone Catherine A. , Mueller Joshua , Fox Laura , Sale Winfield S. , Porter M. E.
Published: February 2013

The nexin–dynein regulatory complex (N-DRC) is proposed to coordinate dynein arm activity and interconnect doublet microtubules. Here we identify a conserved region in DRC4 critical for assembly of the N-DRC into the axoneme. At least 10 subunits associate with DRC4 to form a discrete complex distinct from other axonemal substructures. Transformation of drc4 mutants with epitope-tagged DRC4 rescues the motility defects and restores assembly of missing DRC subunits and associated inner-arm dyneins. Four new DRC subunits contain calcium-signaling motifs and/or AAA domains and are nearly ubiquitous in species with motile cilia. However, drc mutants are motile and maintain the 9 + 2 organization of the axoneme. To evaluate the function of the N-DRC, we analyzed ATP-induced reactivation of isolated axonemes. Rather than the reactivated bending observed with wild-type axonemes, ATP addition to drc-mutant axonemes resulted in splaying of doublets in the distal region, followed by oscillatory bending between pairs of doublets. Thus the N-DRC provides some but not all of the resistance to microtubule sliding and helps to maintain optimal alignment of doublets for productive flagellar motility. These findings provide new insights into the mechanisms that regulate motility and further highlight the importance of the proximal region of the axoneme in generating flagellar bending.
Do Environmental Interventions Impact Elementary School Students' Lunchtime Milk Selection?
Authors: Goto Keiko , Waite Alexandra , Wolff Cindy , Chan Kenny , Giovanni Maria
Published: February 2013

This paper examines whether environmental interventions increase elementary‐school students' selection of white milk in the school cafeteria. At intervention school one, white milk was easily accessible, but students had to ask for chocolate milk. Here, intervention students significantly increased their selection of white milk. Further, there was no significant change in the ratio of white milk consumed to white milk selected during the examined period. At intervention school two, the visual cue of a threefold greater quantity of white compared to chocolate milk did not significantly alter selection patterns. These findings demonstrate that school‐based practices that apply the theory of behavioral economics may offer useful policies and strategies for improving food selections.
propy: a tool to generate various modes of Chou’s PseAAC
Authors: Cao Dong-Sheng , Xu Qing-Song , Liang Yi-Zeng
Published: February 2013

Summary: Sequence-derived structural and physiochemical features have been frequently used for analysing and predicting structural, functional, expression and interaction profiles of proteins and peptides. To facilitate extensive studies of proteins and peptides, we developed a freely available, open source python package called protein in python (propy) for calculating the widely used structural and physicochemical features of proteins and peptides from amino acid sequence. It computes five feature groups composed of 13 features, including amino acid composition, dipeptide composition, tripeptide composition, normalized Moreau–Broto autocorrelation, Moran autocorrelation, Geary autocorrelation, sequence-order-coupling number, quasi-sequence-order descriptors, composition, transition and distribution of various structural and physicochemical properties and two types of pseudo amino acid composition (PseAAC) descriptors. These features could be generally regarded as different Chou’s PseAAC modes. In addition, it can also easily compute the previous descriptors based on user-defined properties, which are automatically available from the AAindex database.

Availability: The python package, propy, is freely available via http://code.google.com/p/protpy/downloads/list, and it runs on Linux and MS-Windows.

Contact:  yizeng_liang@263.net

Supplementary information:  Supplementary data are available at Bioinformatics online.
Cardiac output response to exercise in relation to metabolic demand in heart failure with preserved ejection fraction
Authors: Abudiab Muaz M. , Redfield Margaret M. , Melenovsky Vojtech , Olson Thomas P. , Kass David A. , Johnson Bruce D. , Borlaug Barry A.
Published: February 2013

Aims

Exercise intolerance is a hallmark of heart failure with preserved ejection fraction (HFpEF), yet its mechanisms remain unclear. The current study sought to determine whether increases in cardiac output (CO) during exercise are appropriately matched to metabolic demands in HFpEF.

Methods and results

Patients with HFpEF (n = 109) and controls (n = 73) exercised to volitional fatigue with simultaneous invasive (n = 96) or non‐invasive (n = 86) haemodynamic assessment and expired gas analysis to determine oxygen consumption (VO2) during upright or supine exercise. At rest, HFpEF patients had higher LV filling pressures but similar heart rate, stroke volume, EF, and CO. During supine and upright exercise, HFpEF patients displayed lower peak VO2 coupled with blunted increases in heart rate, stroke volume, EF, and CO compared with controls. LV filling pressures increased dramatically in HFpEF patients, with secondary elevation in pulmonary artery pressures. Reduced peak VO2 in HFpEF patients was predominantly attributable to CO limitation, as the slope of the increase in CO relative to VO2 was 20% lower in HFpEF patients (5.9 ± 2.5 vs. 7.4 ± 2.6 L blood/L O2, P = 0.0005). While absolute increases in arterial–venous O2 difference with exercise were similar in HFpEF patients and controls, augmentation in arterial–venous O2 difference relative to VO2 was greater in HFpEF patients (8.9 ± 3.4 vs. 5.5 ± 2.0 min/dL, P < 0.0001). These differences were observed in the total cohort and when upright and supine exercise modalities were examined individually.

Conclusion

While diastolic dysfunction promotes congestion and pulmonary hypertension with stress in HFpEF, reduction in exercise capacity is predominantly related to inadequate CO relative to metabolic needs.
Towards an interactive electromechanical model of the heart
Authors: Talbot Hugo , Marchesseau Stéphanie , Duriez Christian , Sermesant Maxime , Cotin Stéphane , Delingette Hervé
Published: February 2013

In this work, we develop an interactive framework for rehearsal of and training in cardiac catheter ablation, and for planning cardiac resynchronization therapy. To this end, an interactive and real-time electrophysiology model of the heart is developed to fit patient-specific data. The proposed interactive framework relies on two main contributions. First, an efficient implementation of cardiac electrophysiology is proposed, using the latest graphics processing unit computing techniques. Second, a mechanical simulation is then coupled to the electrophysiological signals to produce realistic motion of the heart. We demonstrate that pathological mechanical and electrophysiological behaviour can be simulated.
New views on cellular uptake and trafficking of manufactured nanoparticles
Authors: Treuel Lennart , Jiang Xiue , Nienhaus Gerd Ulrich
Published: February 2013

Nanoparticles (NPs) are of similar size to typical cellular components and proteins, and can efficiently intrude living cells. A detailed understanding of the involved processes at the molecular level is important for developing NPs designed for selective uptake by specific cells, for example, for targeted drug delivery. In addition, this knowledge can greatly assist in the engineering of NPs that should not penetrate cells so as to avoid adverse health effects. In recent years, a wide variety of experiments have been performed to elucidate the mechanisms underlying cellular NP uptake. Here, we review some select recent studies, which are often based on fluorescence microscopy and sophisticated strategies for specific labelling of key cellular components. We address the role of the protein corona forming around NPs in biological environments, and describe recent work revealing active endocytosis mechanisms and pathways involved in their cellular uptake. Passive uptake is also discussed. The current state of knowledge is summarized, and we point to issues that still need to be addressed to further advance our understanding of cellular NP uptake.
Newcastle disease virus fusion and haemagglutinin-neuraminidase proteins contribute to its macrophage host range
Authors: Cornax Ingrid , Diel Diego G. , Rue Cary A. , Estevez Carlos , Yu Qingzhong , Miller Patti J. , Afonso Claudio L.
Published: February 2013

The fusion (F) and haemagglutinin-neuraminidase (HN) proteins of Newcastle disease
virus (NDV) are multifunctional proteins that play critical roles during infection. Here, we assessed the ability of NDV to replicate in macrophages and investigated the contribution of the F and HN proteins to NDV infection/replication in these cells. Results of our study revealed that, while presenting similar replication kinetics in a fibroblast cell line (DF1) or in primary non-adherent splenocytes, the NDV strain CA02 replicates better in macrophages (HD11 and primary adherent splenocytes) than the NDV strain Anhinga/93. Notably, exchange of the HN or both F and HN genes of NDV Anhinga/93 by the corresponding genes from NDV CA02 markedly improved the ability of the chimeric viruses to replicate in macrophages. These results indicate that the F and HN proteins are determinants of NDV macrophage host range. This represents the first description of productive NDV infection in macrophages.
Creation of a completely helper cell-dependent recombinant morbillivirus
Authors: Baron Jana , Baron Michael
Published: February 2013

We have created a completely helper cell-dependent morbillivirus by modifying the genome to remove the coding sequence of the phosphoprotein (P) and recovering the recombinant virus in a cell line constitutively expressing the P protein. The P protein-deleted virus (P−) grew very inefficiently unless both of the viral accessory proteins (V and C) were also expressed. Growth of the virus was restricted to the P-expressing cell line. The P− virus grew more slowly than the parental virus and expressed much less viral protein in infected cells. The technique could be used to create virus-like particles for use as a vaccine or as antigen in immunological or serological assays.
Spatiotemporal Seed Development Analysis Provides Insight into Primary Dormancy Induction and Evolution of theLepidium DELAY OF GERMINATION1Genes
Authors: Graeber Kai , Voegele Antje , Büttner-Mainik Annette , Sperber Katja , Mummenhoff Klaus , Leubner-Metzger Gerhard
Published: February 2013

Seed dormancy is a block to the completion of germination of an intact viable seed under favorable conditions and is an adaptive and agronomically important trait. Thus, elucidating conserved features of dormancy mechanisms is of great interest. The worldwide-distributed genus Lepidium (Brassicaceae) is well suited for cross-species comparisons investigating the origin of common or specific early-life-history traits. We show here that homologs of the seed dormancy-specific gene DELAY OF GERMINATION1 (DOG1) from Arabidopsis (Arabidopsis thaliana) are widespread in the genus Lepidium. The highly dormant Lepidium papillosum is a polyploid species and possesses multiple structurally diversified DOG1 genes (LepaDOG1), some being expressed in seeds. We used the largely elongated and well-structured infructescence of L. papillosum for studying primary dormancy induction during seed development and maturation with high temporal resolution. Using simultaneous germination assays and marker protein expression detection, we show that LepaDOG1 proteins are expressed in seeds during maturation prior to dormancy induction. Accumulation of LepaDOG1 takes place in seeds that gain premature germinability before and during the seed-filling stage and declines during the late maturation and desiccation phase when dormancy is induced. These analyses of the Lepidium DOG1 genes and their protein expression patterns highlight similarities and species-specific differences of primary dormancy induction mechanism(s) in the Brassicaceae.
Study on thermoelastohydrodynamic performance of bearing with surface roughness considering shaft deformation under load in shaft‐bearing system
Authors: Zhao Xiaoyong , Sun Jun , Wang Chunmei , Wang Hu , Deng Mei
Published: February 2013

Purpose

Current lubrication analyses of misaligned journal bearings are generally performed under some given preconditions. The purpose of this paper is to calculate the lubrication characteristics of a journal bearing with journal misalignment caused by shaft deformation under load, considering the surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface simultaneously.

Design/methodology/approach

The lubrication of bearing was analyzed by average flow model based generalized Reynolds equation. The deformation of bearing surface under pressure or heat of oil film was calculated by compliance matrix method. The compliance matrix was established by finite element analysis. The temperature distributions of oil film and bearing were calculated by energy equation and heat conduction equation.

Findings

When the thermal deformation of bearing and journal surface is considered, the radius clearance affects not only the value of the maximum oil film pressure and minimum oil film thickness, but also the distribution of oil film pressure and thickness of misaligned bearing. The effect of thermal deformation of bearing on the performance of misaligned bearing is larger than that of elastic deformation of bearing. Whether or not the surface roughness affects the performance of misaligned bearing and the affecting level depends greatly on the condition of deformation of bearing surface.

Originality/value

The surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface were considered simultaneously in the thermoelastohydrodynamic lubrication analysis of bearing with journal misalignment caused by shaft deformation under load. The results of this paper are helpful to the design of the bearing.
Accessibility of academic library web sites in North America
Authors: Comeaux Dave , Schmetzke Axel
Published: February 2013

Purpose

The purpose of this paper is to present longitudinal data on the accessibility of 56 North American academic library web sites, as well as insights into the connection between accessibility and certain design methods and technologies.

Design/methodology/approach

Bobby 3.1.1 was used to evaluate compliance with the Web Content Accessibility Guidelines 1.0. Also studied were the main method of page layout (CSS versus HTML tables), whether a content management system was used, and whether skip‐navigation links were employed.

Findings

The percentage of Bobby‐approved pages has remained consistent around 60 per cent in 2010 and 2012. However, the percentage of errors per page, a metric more sensitive to the pervasiveness of accessibility barriers, has steadily and significantly decreased. Sites whose layouts are built with cascading style sheets have fewer errors per page than those that use tables for layout. Sites that use a CMS have considerably higher percentages of approved pages and fewer errors per page than sites that are not built with a CMS.

Research limitations/implications

The principal tool used, Bobby 3.1.1, is capable of detecting only a subset of accessible design principles. Future studies should examine compliance with the newer WCAG 2.0 guidelines.

Practical implications

The use of a content management system may have a positive impact on accessibility. While this study reveals some promising trends, more education and continued advocacy is needed to increase web accessibility at libraries.

Originality/value

This is the only study that provides up‐to‐date trend information about the accessibility of a broader set of academic library web sites (a set not limited to one state) over an extended time period. It is also the only accessibility study comparing academic library web sites that use a content management system to those that do not.
Who is following us? Data mining a library's Twitter followers
Authors: Sewell Robin R.
Published: February 2013

Purpose

Twitter is an increasingly popular social networking tool for libraries to use to reach out to their patrons, but very little research has been done to determine who is following library tweets. The aim of the paper is to use the existing Twitter follower information for the Sterling Evans Library at Texas A&M as a test bed to determine the composition of Evans Twitter followers. The Medical Sciences Library's primary user groups are made up largely of graduate and professional students, making the difference in the number of graduate and undergraduate followers of particular interest.

Design/methodology/approach

Follower data were gathered from the Evans Twitter page and each user was identified and categorized. Additional data were collected on the number of tweets, and the state of the account, active or inactive.

Findings

A total of 432 follower accounts were examined. A total of 54.37 percent were identified as affiliated with Texas A&M University. The largest group of followers were students (23.61 percent), made up primarily of undergraduates (81.05 percent). Faculty/staff (7.64 percent) showed very little participation. Unaffiliated followers included corporations (19.68 percent), alumni (11.57 percent), and other libraries or librarians (7.64 percent).

Originality/value

Very little can be found in the library literature on Twitter follower analysis. This is the first large and detailed analysis of library Twitter followers.
30 days to first decision: time span in Library Hi Tech from submission to first decision
Authors: Greifeneder Elke
Published: February 2013

Purpose

The purpose of this editorial is to describe how long it takes a manuscript to go through peer review within Library Hi Tech and how (potential) authors can speed up the reviewing time for their article.

Design/methodology/approach

The editorial describes the three distinct time spans during the reviewing process and five rules to make the reviewing process faster and more successful.

Findings

The editorial shows that Library Hi Tech requires on average less than 30 days from submission to a first decision and that the reviewing process can be speed up if authors follow five rules, which are described in the editorial.

Originality/value

The editorial will help to understand why the reviewing process requires so much time and it can serve as guide for submissions for future authors.