bluuebunny/crossref_metadata_2025_split huggingface dataset:
A numerical study of the effects of bell pulsation dynamics and oral arms on the exchange currents generated by the upside-down jellyfish Cassiopea xamachana
Authors: Hamlet Christina , Santhanakrishnan Arvind , Miller Laura A. 
Published: May 2011

SUMMARY
Mathematical and experimental studies of the flows generated by jellyfish have focused primarily on mechanisms of swimming. More recent work has also considered the fluid dynamics of feeding from currents generated during swimming. Here we capitalize on the benthic lifestyle of the upside-down jellyfish (Cassiopea xamachana) to explore the fluid dynamics of feeding uncoupled from swimming. A two-dimensional mathematical model is developed to capture the fundamental characteristics of the motion of the unique concave bell shape. Given the prominence of the oral arms, this structure is included and modeled as a porous layer that perturbs the flow generated by bell contractions. The immersed boundary method is used to solve the fluid–structure interaction problem. Velocity fields obtained from live organisms using digital particle image velocimetry were used to validate the numerical simulations. Parameter sweeps were used to numerically explore the effects of changes in pulse dynamics and the properties of the oral arms independently. Numerical experiments allow the opportunity to examine physical effects and limits within and beyond the biologically relevant range to develop a better understanding of the system. The presence of the prominent oral arm structures in the field of flow increased the flux of new fluid from along the substrate to the bell. The numerical simulations also showed that the presence of pauses between bell expansion and the next contraction alters the flow of the fluid over the bell and through the oral arms.
Coordination of cytochrome c oxidase gene expression in the remodelling of skeletal muscle
Authors: Duggan Ana T. , Kocha Katrinka M. , Monk Christopher T. , Bremer Katharina , Moyes Christopher D. 
Published: May 2011

SUMMARY
Many fish species respond to low temperature by inducing mitochondrial biogenesis, reflected in an increase in activity of the mitochondrial enzyme cytochrome c oxidase (COX). COX is composed of 13 subunits, three encoded by mitochondrial (mt)DNA and 10 encoded by nuclear genes. We used real-time PCR to measure mRNA levels for the 10 nuclear-encoded genes that are highly expressed in muscle. We measured mRNA levels in white muscle of three minnow species, each at two temperatures: zebrafish (Danio rerio) acclimated to 11 and 30°C, goldfish (Carassius auratus) acclimated to 4 and 35°C, and northern redbelly dace (Chrosomus eos) collected in winter and summer. We hypothesized that temperature-induced changes in COX activity would be paralleled by COX nuclear-encoded subunit transcript abundance. However, we found mRNA for COX subunits showed pronounced differences in thermal responses. Though zebrafish COX activity did not change in the cold, the transcript levels of four subunits decreased significantly (COX5A1, 60% decrease; COX6A2, 70% decrease; COX6C, 50% decrease; COX7B, 55% decrease). Treatments induced changes in COX activity in both dace (2.9 times in winter fish) and goldfish (2.5 times in cold fish), but the response in transcript levels was highly variable. Some subunits failed to increase in one (goldfish COX7A2, dace COX6A2) or both (COX7B, COX6B2) species. Other transcripts increased 1.7–100 times. The most cold-responsive subunits were COX4-1 (7 and 21.3 times higher in dace and goldfish, respectively), COX5A1 (13.9 and 5 times higher), COX6B1 (6 and 10 times higher), COX6C (11 and 4 times higher) and COX7C (13.3 and 100 times higher). The subunits that most closely paralleled COX increases in the cold were COX5B2 (dace 2.5 times, goldfish 1.7 times) and COX6A2 (dace 4.1 times, goldfish 1.7 times). Collectively, these studies suggest that COX gene expression is not tightly coordinated during cold-induced mitochondrial remodelling in fish muscle. Further, they caution against arguments about the importance of transcriptional regulation based on measurement of mRNA levels of select subunits of multimeric proteins.
Hydrodynamic discrimination of wakes caused by objects of different size or shape in a harbour seal (Phoca vitulina)
Authors: Wieskotten Sven , Mauck Björn , Miersch Lars , Dehnhardt Guido , Hanke Wolf 
Published: May 2011

SUMMARYHarbour seals can use their mystacial vibrissae to detect and track hydrodynamic wakes. We investigated the ability of a harbour seal to discriminate objects of different size or shape by their hydrodynamic signature and used particle image velocimetry to identify the hydrodynamic parameters that a seal may be using to do so. Hydrodynamic trails were generated by different sized or shaped paddles that were moved in the calm water of an experimental box to produce a characteristic signal. In a two-alternative forced-choice procedure the blindfolded subject was able to discriminate size differences of down to 3.6 cm (Weber fraction 0.6) when paddles were moved at the same speed. Furthermore the subject distinguished hydrodynamic signals generated by flat, cylindrical, triangular or undulated paddles of the same width. Particle image velocimetry measurements demonstrated that the seal could have used the highest velocities and the steepness of the gradients within the wake to discriminate object size, beside the size of counter-rotating vortices and the spatial extension of a wake. For shape discrimination the subject could have used the spatial extension of the whole wake, in addition to the arrangement of the vortices. We tested whether the seal used highest velocities, the steepness of the gradients and the spatial extension of the wake in a second set of experiments by varying moving speed and paddle size, respectively. The subject was still able to discriminate between the respective object sizes, but the minimum detectable size difference increased to 4.4 cm (Weber fraction 3.6). For the shape discrimination task, the seal was only able to distinguish flat from triangular paddles. Our results indicate that the seal's discrimination abilities depend on more than one hydrodynamic parameter.
Synthesis and Stereochemical Behavior of (E)-Cyclononene Derivatives
Authors: Tomooka Katsuhiko , Inoue Hiroko , Igawa Kazunobu 
Published: May 2011

Abstract
A versatile synthetic approach to planar chiral molecules from (E)-5-cyclononen-1-one (1) has been developed; these molecules have multifunctionalities with (E)-cyclononene skeleton. The newly synthesized keto-ester 3 having central chirality shows labile planar chirality. In contrast, enol derivative 4 and enyne 5 show robust planar chirality.
Photoisomerization and Fluorescence Characteristics of Tetramethoxystilbene in Ionic Liquid
Authors: Tamura Hiroyasu , Arai Tatsuo 
Published: May 2011

Abstract
Photochemical behavior of 3,3′,5,5′-tetramethoxystilbene (TMST) has been explored in ionic liquid. Two fluorescence components with the lifetime of 4.3 and 23.0 ns were observed for trans-TMST in ionic liquid solution. From this experimental evidence one could propose that ionic liquid may provide two different environments with highly different polarity, nonpolar and highly polar environments.
Prevalence of HIV in the Mthatha area of South Africa, as estimated from the testing of rape victims
Authors: Meel Banwari , Kwizera Enoch 
Published: May 2011

Background Tremendous challenges remain in the field of HIV education, prevention and care in South Africa. There is conflicting data on the prevalence of HIV in South Africa from two major studies. Antenatal surveillance showed 29.5% prevalence whereas a household HIV survey showed a prevalence nearly half of that, at 16.2%. There is therefore a need for a third estimate in this situation. Objective To estimate HIV prevalence in the Mthatha area of South Africa. Methods Retrospective review of HIV testing results among victims of sexual assault who presented for the first time to the Sinawe Referral Centre, Mthatha General Hospital, for the period 2001–2005 (inclusive). Results Between 2001 and 2005, 1691 victims of sexual assault presented to the Sinawe Referral Centre. Of these 1435 (84.8%) were tested for HIV at the time of first consultation. One hundred and ninety-seven were found to be HIV positive on the screening test. In a space of five years (2001–2005), there was an increase in HIV prevalence from 0.9% to 6.4%. The highest HIV positive rate (3.7%) was found in the 16–20 year age group. Conclusion The HIV prevalence rate is 13.7% in the Mthatha area, and just over a half (7%) of HIV-positive rape survivors were aged 16–25 years.
Improved Reflexive Testing Algorithm for Hepatitis C Infection Using Signal-to-Cutoff Ratios of a Hepatitis C Virus Antibody Assay
Authors: Lai Keane KY , Jin Ming , Yuan Shan , Larson Meaghan F , Dominitz Jason A , Bankson Daniel D 
Published: May 2011

BACKGROUND
Chemiluminescence immunoassay (CIA) is used to detect hepatitis C virus (HCV) antibody status on the basis of signal-to-cutoff (S/Co) ratios. Positive results of antibody to HCV (anti-HCV) are followed by either recombinant immunoblot assay (RIBA) to confirm anti-HCV positivity or reverse transcription (RT)-PCR to detect viremia. We hypothesized that by analyzing S/Co ratios, we could determine a strategy to reduce unnecessary supplementary testing in our population.

METHODS
CIA was performed to screen for anti-HCV, and positive results were followed up with RT-PCR testing. Negative RT-PCR results were followed up with RIBA, whereas positive RT-PCR results were assumed to be RIBA positive. ROC curves were analyzed to determine the optimal S/Co ratios to predict HCV infection.

RESULTS
We determined the S/Co ratios on 34 243 veteran patient samples. We found that with the CIA method 9.0% of patients had positive test results for anti-HCV. An S/Co ratio &lt;3.0 ruled out active HCV infection and exposure with 100% negative predictive value. When the S/Co ratio was ≥20.0, positive predictive values were 98.5% compared with RIBA results, and 81.0% compared with RT-PCR results.

CONCLUSIONS
RIBA is not necessary to confirm negative or positive CIA anti-HCV if the S/Co ratio is &lt;3.0 or ≥20.0, respectively. To confirm HCV exposure, samples with an S/Co ratio between 3.0 and 19.9 should be followed up with RIBA unless PCR testing has been performed and the result is positive. Samples with an S/Co ratio ≥20.0 or positive RIBA results should be further tested by RT-PCR to determine HCV viremia status.
Multi-steps degradation method for β-O-4 linkage in lignins: γ-TTSA method. Part 1: Reaction of non-phenolic dimeric β-O-4 model compounds
Authors: Ando Daisuke , Takano Toshiyuki , Nakatsubo Fumiaki 
Published: May 2011

Abstract
The so-called γ-TTSA method has been developed for the cleavage of β-O-4 linkages in lignin. It consists of four steps: (1) γ-tosylation, (2) thioetherification (substitution reaction with 1-dodecanethiol to γ-thioether), (3) sulfonylation (oxidation from γ-thioether to γ-sulfone), and (4) mild alkali degradation of γ-sulfone. The method was tested on non-phenolic dimeric β-O-4 lignin model compounds: 1G (4-benzyloxy-3-methoxyphenylglycerol-β-guaiacyl ether), 1S (4-benzyloxy-3,5-dimethoxyphenylglycerol-β-syringyl ether), and 1H (4-benzyloxyphenylglycerol-β-phenyl ether). It is demonstrated that the mild alkali degradation of the γ-sulfone group proceeds efficiently, i.e., the electron-withdrawing sulfone group at γ-position contributes to the cleavage of β-O-4 linkages. The γ-TTSA method may be especially useful for the elucidation of lignin-carbohydrate complex structures containing benzylether bonds.
Merkmal(s?)analyse, Seminar(s?)arbeit und Essen(s?)ausgabe: Zweifelsfälle der Verfugung als Indikatoren für Sprachwandel
Authors: Nübling Damaris , Szczepaniak Renata 
Published: May 2011

Abstract
Contemporary German abounds in doubtful cases where linking elements alternate with zero elements, such as Seminar(+s?+)arbeit ‘term paper’, Respekt(+s?+)person ‘person who commands respect”. This variation indicates a profound language change in the course of which the linking +s+ has spread continuously since Early New High German and is replacing the zero element more and more often. Today, +s+ is the most productive, progressive and most frequently occurring linking element. In this paper, we provide an explanation for the doubtful cases. Most often, the linking +s+ depends directly on the phonological quality of the first part of the compound: the worse its phonological structure, the more likely the occurrence of the linking +s+. It occurs most regularly after first parts of compounds containing a suffix or an unstressed prefix (Verkáuf+s+gespräch ‘sales conversation’), while words with an ideal phonological structure (monosyllabic or trochaic words) rarely attract the linking +s+. The variation concentrates on compounds whose first parts feature a stressed prefix (Éinkauf(+s?+)führer ‘shopping guide’). There is, however, a further factor which leads to fluctuation in the occurrence of the linking +s+. In cases where the second part of synthetic compounds such as Auftrag(+s?+)geber ‘client’ contain a high degree of verbality, the linking +s+ blurs the syntactic relation between the immediate constituents, strengthening the morphological character of the compound.
Towards Social Crowd Environments Using Service-Oriented Architectures
Authors: Skopik Florian , Schall Daniel , Psaier Harald , Treiber Martin , Dustdar Scharam 
Published: May 2011

Abstract
Crowdsourcing has emerged as an important paradigm of human problem solving techniques on the Web. More often than noticed, organizations outsource tasks to humans which cannot be processed by software. In this work we demonstrate the application of service-oriented architectures (SOA) for enterprise crowdsourcing. Crowdsourcing applications typically utilize the capabilities of people in open and dynamic Web-based systems. We extend this concept and introduce knowledge crowds where crowd members collaborate in context of joint tasks. Interactions in such environments are performed using software services. Such highly dynamic socio-technical environments, however, demand for flexible interaction models due to varying interaction styles of people and services. Our main contribution centers around the convergence of process artifacts and emerging social structures. Here, we present the implementation of a real world example, a human assisted image processing service that is provided by a knowledge crowd. We discuss the foundational building blocks for realizing the design, execution, and adaptation of service-oriented crowdsourcing applications.
Broadening Participation in Knowledge Management in Enterprise 2.0
Authors: Back Andrea , Koch Michael 
Published: May 2011

Abstract
Enterprise 2.0 is an approach to broaden participation of employees in enterprise knowledge management. Building on concepts and tools from the Web 2.0, the effort to participate is minimized and a broad audience is provided. This has positive effects on the motivation of employees to participate. In this article we present an overview of the ideas and tools behind Enterprise 2.0, and discuss challenges and approaches for management.
Thin coatings of ceramics: some new developments in France and in Europe
Authors: Sciau Ph. , Leon Y. 
Published: May 2011

ABSTRACTThe aim of this paper is to focus attention on some current developments in the physical examination of decorative ceramic thin coatings performed in France and in Europe. Thanks to the recent progress in instrumentation and the implication of material science teams, significant new results were obtained concerning the finishing coatings of ceramic ware, and specially regarding the luster decorations of Islamic medieval potteries and the high gloss coatings of Greek and Roman ceramics.
Science at the Interface with Art
Authors: Madsen Lynnette D. , Rosenzweig Zeev , Cook Kelsey D. , Scott Michael J. , Jacobson Amy M. 
Published: May 2011

ABSTRACTThe Cultural Heritage Science (CHS, formerly SCIART) Program seeks to enhance opportunities for chemistry and materials research at the interface between science and art. The objective is to promote collaboration between cultural heritage scientists, mainly located in US museums and chemists and/or materials scientists in US academic institutions to address grand challenges in the science of cultural heritage. Through the first competition, eight projects, two to three years in duration, were funded at $270,000 to 495,000 each. Every successful proposal demonstrated a clear need for collaboration with good synergy between the collaborating groups, and provided plans for meaningful training experiences for students and/or postdoctoral researchers in the field of cultural heritage science. It is anticipated that the CHS Program will continue for two additional years in a similar fashion. During this period, researchers should be able to more easily identify the disciplinary programs in materials research or chemistry relevant to their work, and their proposals will be reviewed together in panels. Proposals falling outside of the CHS specifications may be submitted directly to the relevant program/s of interest at the National Science Foundation (NSF) as unsolicited proposals. After the CHS Program ends, unsolicited proposals will remain the key mechanism for obtaining NSF funding in this research area.
Deterioration in Abstract Expressionist Paintings: Analysis of Zinc Oxide Paint Layers in Works from the Collection of the Hirshhorn Museum and Sculpture Garden, Smithsonian Institution
Authors: Maines Christopher A. , Rogala Dawn , Lake Susan , Mecklenburg Marion 
Published: May 2011

ABSTRACTA recent visual survey of Abstract Expressionist-era paintings in the collection of the Hirshhorn Museum and Sculpture Garden (HMSG), Smithsonian Institution revealed a particular type of paint layer separation. Earlier work by the authors showed that zinc oxide in oil paint is a contributing factor to the problem. Ten samples from five Abstract Expressionist-era paintings as well as twenty-three samples eight years or older from the Smithsonian Institution’s (SI) Materials Study Collection were analyzed by pyrolysis – gas chromatography – mass spectrometry (Py-GC-MS), and unexpectedly significant amounts of oleic (cis-octadecenoic) acid were detected in samples containing high proportions of zinc oxide (25 % or greater by weight). In a typical fully cured oil paint, the oleic acid is oxidized to azelaic (nonanedioic) acid. Although the formation of zinc soaps in oil paints is well-known, the detection of zinc oleate in paints by Py-GC-MS has never been described. The close-packing of the oleate chains in the plate-like structure of zinc oleate prevents the oxidation of the cis-double bond, and therefore prevents the formation of azelaic acid. The detection of zinc oleate in paintings is an indication that the paint layers are at risk for future separation.
Metallography, Microanalysis & Corrosion of the Athlit Ram
Authors: Notis M. R. , Hoban M. , Wang D-N. 
Published: May 2011

ABSTRACTThe Athlit ram, a bronze warship ram from a 2nd Century BCE Roman-era galley, was found in 1980 off the coast of Israel at Athlit, and is now displayed at the National Maritime Museum, Haifa, Israel. It meant to fit on the prow of a medium-sized oared warship. This ram is the only known surviving example of this ancient naval weapon. Inside the bronze ram some of the ship’s wood is still preserved. We have recently studied a piece of the ram removed during early conservation. Remnant metal, corrosion products, and mineralized and pseudomorphed wood have all been found and examined by light optical metallography, x-ray diffraction, scanning electron microscopy, and microanalysis using energy dispersive x-ray mapping. The main corrosion product on the Athlit Ram is identified as covellite (CuS), and the entrained material is pseudomorphed cedar wood. Analysis indicates the lumen to be replaced by calcium carbonate and the cell walls to be replaced by covellite, consistent with the matrix.
Influences of Internal Tapered Abutment Designs on Bone Stresses Around a Dental Implant: Three‐Dimensional Finite Element Method With Statistical Evaluation
Authors: Chu Chun‐Ming , Huang Heng‐Li , Hsu Jui‐Ting , Fuh Lih‐Jyh 
Published: May 2011

Background: The aim of this study is to determine the effects of various designs of internal tapered abutment joints on the stress induced in peri‐implant crestal bone by using the three‐dimensional finite element method and statistical analyses.Methods: Thirty‐six models with various internal tapered abutment–implant interface designs including different abutment diameters (3.0, 3.5, and 4.0 mm), connection depths (4, 6, and 8 mm), and tapers (2°, 4°, 6°, and 8°) were constructed. A force of 170 N was applied to the top surface of the abutment either vertically or 45° obliquely. The maximum von Mises bone‐stress values in the crestal bone surrounding the implant were statistically analyzed using analysis of variance. In addition, patterns of bone stress around the implant were examined.Results: The results demonstrate that a smaller abutment diameter and a longer abutment connection significantly reduced the bone stresses (P <0.0001) in vertical and oblique loading conditions. Moreover, when the tapered abutment–implant interfaced connection was more parallel, bone stresses under vertical loading were less (P = 0.0002), whereas the abutment taper did not show significant effects on bone stresses under oblique loading (P = 0.83). Bone stresses were mainly influenced by the abutment diameter, followed by the abutment connection depth and the abutment taper.Conclusion: For an internal tapered abutment design, it was suggested that a narrower and deeper abutment–implant interface produced the biomechanical advantage of reducing the stress concentration in the crestal region around an implant.
Intraoperative Bleeding During Open Flap Debridement and Regenerative Periodontal Surgery
Authors: Zigdon Hadar , Levin Liran , Filatov Margarita , Oettinger‐Barak Orit , Machtei Eli E. 
Published: May 2011

Background: The objective of this study was to measure the intraoperative bleeding during periodontal flap surgery.Methods: Patients scheduled for periodontal surgery were recruited for this study. Data regarding smoking habits, general health, and medications were collected. The amount of the local anesthetic that was injected was then recorded, as well as the number of teeth in the operative field and the duration of the procedure. During surgery, the liquids from the oral cavity were suctioned and collected into a sterile empty vial. To calculate the net amount of blood volume in the liquids, colorimetric assay using capillary blood fructosamine as a reference molecule was used.Results: Twenty‐six patients were included in this study. The amount of blood lost during the procedure ranged from 6.0 to 145.1 mL, with an overall mean of 59.47 ± 38.2 mL. Patients taking aspirin (acetylsalicylic acid) showed mean blood loss of 43.26 ± 31.5 mL, whereas the mean blood loss among patients that did not use this medication was higher (65.4 ± 39.4 mL) but not statistically significant. Local anesthetic amount, surgical field size, and the operation duration did not relate to blood‐loss volume. The mean blood loss among current smokers was significantly higher (96.47 ± 44.2 mL) compared to former (12 ± 8.4 mL) or never (54.74 ± 30.5 mL, P = 0.011) smokers.Conclusion: The results of the current study support previous papers and confirm that blood loss during periodontal surgery is minimal.