bluuebunny/crossref_metadata_2025 huggingface dataset:
Educator-Coach as Stranger
Authors: Gearity Brian T. , Denison Jim
Published: June 2012

The recent allegations of widespread child abuse at Penn State add to the already lengthy and never ending litany of scandals and problems associated within and around intercollegiate athletics. We begin this article by briefly situating these abuses within their socio-historical context and the complex power relations of intercollegiate athletics. We surmise that the economic, social, and moral problems associated with intercollegiate athletics (including Penn State) are nothing new, although they are currently receiving greater attention and scrutiny from scholars and the media. While criticizing intercollegiate athletics consistent inability to align itself with educational values and govern its coaches is worthwhile, its constituents comprise a tiny fraction of all sporting participants. We argue that a more prudent way forward for sport, at all levels, is through coach education and increased regulation. Curiously, the preparation and regulation of coaches has been a major omission from American society. In order to rectify these concerns, we conclude that now is the time to make the educator-coach the new norm
All Things in Moderation
Authors: Rinehart Robert E.
Published: June 2012

This piece is about remembrance and forgetting; about shame and forgiveness; about capitalist media and the victimization of vulnerable citizens.
White structure flaking (WSF) in wind turbine gearbox bearings: Effects of ‘butterflies’ and white etching cracks (WECs)
Authors: Evans M-H
Published: June 2012

The actual service life of wind turbine gearboxes is often well below the desired 20 years. One of the prevalent failure modes in gearbox bearing raceways is white structure flaking (WSF) by the formation of butterflies and white etching cracks with associated microstructural change called white etching areas. Despite these failures having been observed for two decades in various industries, the detailed reasons and mechanisms for their formation are not fully understood. In this review, white etching area formation mechanisms are discussed, specifically grain refinement, and effects of carbon/carbide in a range of bearing steels of widely differing carbon content. The review also highlights the severe transient, cyclic loading and tribochemical operating conditions of gearbox bearings and explains how these may act as drivers to produce WSF. Much previous research has focused on the detrimental effects of hydrogen, but other work suggests that hydrogen is not the only cause for WSF. Possible methods for preventing WSF are discussed, with attention paid to special steels such as high chromium steels, low carbon stainless nitrogen alloy steels and carbonitrided steels. Beneficial compressive residual stresses, surface coatings and enhanced lubrication and additive packages are shown to offer degrees of prevention, although the mechanisms leading to improvements are not fully understood.
Bearing steel quality and bearing performance
Authors: Trojahn W , Valentin P
Published: June 2012

For pricing reasons the extent of metallurgical treatment often is questioned about its influence on bearing performance. In this paper steels with three different quality levels are compared with regards to cleanliness and fatigue resistance.
Work hardening response of M50-NiL case hardened bearing steel during shakedown in rolling contact fatigue
Authors: Arakere N K , Subhash G
Published: June 2012

The work hardening response during shakedown phase for case hardened M50-NiL bearing steel in rolling contact fatigue (RCF) is presented. Rolling contact fatigue testing is performed using a ball rod tester for varying cycles and Hertzian stress of 5·5 GPa on multiple test tracks of a case hardened rod. Longitudinal sectioning and polishing of the test rod reveal the RCF affected zones. Micro-Vickers indentation mapping of the subsurface zones is used to measure workhardening. A maximum increase in hardness from 7·4 to 8·3 GPa was observed at ∼13·5×106 cycles, after which hardness saturated. A finite element simulation of the RCF test was performed to predict the increase in hardness. It is hypothesised that plastic strain accumulation around the hard carbide inclusions results in increased hardness. Cyclic hardening likely saturates when the ratchet strain per cycle approaches zero. Plastic shakedown follows with no further accumulation of plastic strain and marks the beginning of steady state response.
Effect of sulphide inclusions on rolling contact fatigue life of bearing steels
Authors: Hashimoto K , Hiraoka K , Kida K , Costa Santos E
Published: June 2012

Flaking failure in rolling contact fatigue (RCF) of hardened bearing steel under well controlled lubrication is known to originate primarily from non-metallic inclusions. Among several different types of defects inevitably present in steels, the influence of sulphides on the RCF performance of steel is an issue that still raises many questions and controversies. In the present study, our objective is to investigate this matter by observing cracks initiating from sulphides after RCF testing. To accelerate bearing failure, high Hertzian stresses of 5·3 GPa were used. It was found that cracks initiated from the elongated tips of sulphides and propagated to a direction parallel to the direction of load movement. This rule was true regardless of the relationship between the direction of load movement and the elongation direction of sulphides. We concluded that sulphides could be a dominant factor in RCF life when the harmful oxide effect was excluded.
Gigacycle fatigue of bearing steels
Authors: Bathias C
Published: June 2012

For a practical point of view, the bearing steels are loaded up to the very high cycle fatigue regime, in service, far away from the Wöhler regime. In the present paper, several approaches are discussed in order to open some ways of investigation, in the range of 109 cycles: accelerated fatigue testing, thermal dissipation, fish-eye formation, inclusion effect, short crack propagation and stability of the microstructure.
Interaction of grain refinement with B and modification with Sr in aluminium foundry alloys
Authors: Birol Y
Published: June 2012

The interaction between modification with Sr and grain refinement with B was investigated to ensure a very fine grained matrix and a very fine fibrous eutectic in the AlSi7Mg alloy. The grain refinement offered by B is remarkable. B (200 ppm) refines the grain structure of the AlSi7Mg alloy at least 10 times in a wide range of cooling rates between 0·1 and 10 K s−1, whether added before or after Sr. While a weak grain refiner, Sr turns the coarse Si plates and needles into fine fibres. However, the modification capacity of Sr is impaired when there is B in the melt, possibly due to the formation of SrB6 compound. The poisoning in the chemical modification of the eutectic phase in grain refined Al–Si alloys can be circumvented by quench modification. It takes cooling rates in the order of 10 K s−1 to adequately modify the eutectic phase in the Sr free grain refined AlSi7Mg alloy. Si fibres are still the predominant feature at lower cooling rates (1–10 K s−1) when modification of the eutectic phase relies not only on rapid solidification but also on Sr. Coarse Si plates and needles form only at very low cooling rates, well below 1 K s−1. It is fair to claim that 200 ppm B may suffice for a sound structure in casting processes, which involve rapid solidification and thin sections, while Sr is needed for an acceptable modification of the eutectic phase when solidification is relatively slower.
HIV-1 infection of human macrophages directly induces viperin which inhibits viral production
Authors: Nasr Najla , Maddocks Susan , Turville Stuart G. , Harman Andrew N. , Woolger Natalie , Helbig Karla J. , Wilkinson John , Bye Chris R. , Wright Thomas K. , Rambukwelle Dharshini , Donaghy Heather , Beard Michael R. , Cunningham Anthony L.
Published: June 2012

Macrophages are key target cells for HIV-1. HIV-1BaL induced a subset of interferon-stimulated genes in monocyte-derived macrophages (MDMs), which differed from that in monocyte-derived dendritic cells and CD4 T cells, without inducing any interferons. Inhibition of type I interferon induction was mediated by HIV-1 inhibition of interferon-regulated factor (IRF3) nuclear translocation. In MDMs, viperin was the most up-regulated interferon-stimulated genes, and it significantly inhibited HIV-1 production. HIV-1 infection disrupted lipid rafts via viperin induction and redistributed viperin to CD81 compartments, the site of HIV-1 egress by budding in MDMs. Exogenous farnesol, which enhances membrane protein prenylation, reversed viperin-mediated inhibition of HIV-1 production. Mutagenesis analysis in transfected cell lines showed that the internal S-adenosyl methionine domains of viperin were essential for its antiviral activity. Thus viperin may contribute to persistent noncytopathic HIV-1 infection of macrophages and possibly to biologic differences with HIV-1–infected T cells.
Chain Shifting and Centralization in California Vowels: An Acoustic Analysis
Authors: Kennedy Robert , Grama James
Published: June 2012

This article documents the acoustic properties of the vowels of young adults from various regions of California, with special attention to a chain shift that lowers short front vowels /I/ (as in kit), /ϵ/ (as in dress), and /æ/ (as in trap). It also tracks the centralization of /ow/ (as in goat). Quantitative analysis of subjects' formants shows a consistently lower set of front vowels and a consistently centralized /ow/ relative to baseline comparisons drawn from Labov, Ash, and boberg's 2006 Atlas of North American English, suggesting a recent diachronic emergence of both phenomena. A small gender effect is observed, suggesting women are further advanced than men in the chain shift. These findings suggest that the chain shift is not clearly a pull-chain brought about by the low-back merger of /Ɔ/ (as in lot) and /ɑ/ (as in thought) and may have occurred independently as a push-train.
Al Qaeda’s Post–9/11 Organizational Structure and Strategy: The Role of Islamist Regional Affiliates
Authors: Celso Anthony N.
Published: June 2012

The political transformations under way in the Arab world and the killing of Osama bin Laden raise serious questions about al Qaeda’s long-term viability. The secular-liberal Arab Spring protest movement appears to be winning the war of ideas over al Qaeda’s violent religious fundamentalism. Civil disobedience campaigns in Tunisia and Egypt succeeded in forcing regime change in ways that a decade of al Qaeda terror attacks failed to accomplish. While it is too soon to write al Qaeda’s obituary, its erosion came well before the death of its historic leader. This essay examines al Qaeda’s post–9/11 evolution, its strategy, and its steady fragmentation. Since the destruction of its Taliban Afghan sanctuary, al Qaeda has been through many mutations, none of which, over time, has been successful. This essay argues that al Qaeda’s failures in Iraq contributed substantially to the organization’s decline.
Information, Animal Spirits, and the Meaning of Innovations in Consumer Confidence
Authors: Barsky Robert B , Sims Eric R
Published: June 2012

Innovations to consumer confidence convey incremental information about economic activity far into the future. Does this reflect a causal effect of animal spirits on economic activity, or news about exogenous future productivity received by consumers? Using indirect inference, we study the impulse responses to confidence innovations in conjunction with an appropriately augmented New Keynesian model. While news, animal spirits, and pure noise all contribute to confidence innovations, the relationship between confidence and subsequent activity is almost entirely reflective of the news component. Confidence innovations are well characterized as noisy measures of changes in expected productivity growth over a relatively long horizon. (JEL D12, D83, D84, E12)
Understanding Bank Runs: The Importance of Depositor-Bank Relationships and Networks
Authors: Iyer Rajkamal , Puri Manju
Published: June 2012

We use unique depositor-level data for a bank that faced a run to understand the factors that affect depositor behavior. We find uninsured depositors are most likely to run. Deposit insurance helps, but is only partially effective. Bank-depositor relationships mitigate runs, suggesting that relationship with depositors help banks reduce fragility. In addition, we also find that social networks matter. Finally, we find long-term effects of a solvent bank run in that depositors who run do not return back to the bank. Our results help understand the underlying dynamics of bank runs and hold important policy implications. (JEL D12, G21, O16, Z13)
On the Timing and Pricing of Dividends
Authors: Binsbergen Jules van , Brandt Michael , Koijen Ralph
Published: June 2012

We present evidence on the term structure of the equity premium. We recover prices of dividend strips, which are short-term assets that pay dividends on the stock index every period up to period T and nothing thereafter. It is short-term relative to the index because the index pays dividends in perpetuity. We find that expected returns, Sharpe ratios, and volatilities on short-term assets are higher than on the index, while their CAPM betas are below one. Short-term assets are more volatile than their realizations, leading to excess volatility and return predictability. Our findings are inconsistent with many leading theories.
The Currency of Reciprocity: Gift Exchange in the Workplace
Authors: Kube Sebastian , Maréchal Michel André , Puppe Clemens
Published: June 2012

What determines reciprocity in employment relations? We conducted a controlled field experiment to measure the extent to which monetary and nonmonetary gifts affect workers' performance. We find that nonmonetary gifts have a much stronger impact than monetary gifts of equivalent value. We also observe that when workers are offered the choice, they prefer receiving money, but reciprocate as if they received a nonmonetary gift. This result is consistent with the common saying, “it's the thought that counts.” We underline this point by showing that monetary gifts can effectively trigger reciprocity if the employer invests more time and effort into the gift's presentation.
Risk Aversion and the Labor Margin in Dynamic Equilibrium Models
Authors: Swanson Eric T
Published: June 2012

The household's labor margin has a substantial effect on risk aversion, and hence asset prices, in dynamic equilibrium models even when utility is additively separable between consumption and labor. This paper derives simple, closed-form expressions for risk aversion that take into account the household's labor margin. Ignoring this margin can dramatically overstate the household's true aversion to risk. Risk premia on assets priced with the stochastic discount factor increase essentially linearly with risk aversion, so measuring risk aversion correctly is crucial for asset pricing in the model.
Choice or Mimetism in the Decision to Migrate? A European Illustration
Authors: Warin Thierry , Blakely Andrew
Published: June 2012

This paper examines how herd behavior (mimetism) and network effects determine bilateral migration flows to thirteen EU-15 countries. Using an adapted gravity model controlling for economic activity, welfare progressivity, as well as geospatial and historic relationships, the results force us to question our explanations for migration flows. Herd behavior positively influences European migration flows, whereas network complementarities in the receiving country do not consistently predict, and may in some cases reduce, the likelihood of immigrant inflows. Moreover, economic activity, particularly labor market conditions, plays a lesser role in the migrants’ choice of destination than was previously thought. The introduction of herd behavior as a determinant of European Migration in our empirical analysis hopefully will change the paradigm for understanding migration.
Have Migrants Bought a "Round Trip Ticket"? Determinants in Probability of Immigrants' Return in Spain
Authors: de Arce Rafael , Mahia Ramon
Published: June 2012

Understanding the extent to which immigration is a predominantly permanent or transitory phenomenon is essential for host countries insofar as it affects the strategic design of their admission, reception, and integration policies. Beyond the determination of the volume of returns, it is crucial to also determine which covariates connect better with a greater or lesser propensity of return. An adequate approach to the dynamics of the return requires considering this decision conditioned by the time elapsed since the arrival of the immigrant. From this perspective, the variable of interest would not be the intention of return, but the elapsed time between the arrival of the immigrant and the moment that return is considered as an option, as well as what are the factors affecting a greater or lesser duration of the stay. In this context, the article explores the relative importance of various personal and migration characteristics in the intention of return of immigrants conditional at the time of residence through the application of a Cox model of duration.
Effects of Temperature and Sugar Concentration on the Colour Development, 5-hydroxymethoxylfurfural Production, and Antioxidative Activity Development in the Caramelisation of Acidic Glucose Solution
Authors: Chen Mei-Ling , Chen Hsin-Yi , Liu* Shih-Chuan
Published: June 2012

Model acidic glucose solution systems (pH 3.0) incubated at 75 - 95°C were utilized for investigating the reaction kinetics of the brown colour development, DPPH radical scavenging activity (SDPPH) and 5-hydroxymethoxylfurfural (HMF) production of caramelisation. The result showed the reaction model of glucose on the caramel brown colour development followed first-order kinetics at 75 and 85˚C, and logarithm-order at 95˚C. The reaction models of glucose on SDPPH development and HMF production followed first-order kinetics through the experimental temperature ranges. The Ea values for glucose on caramel brown colour development, SDPPH development and HMF production were 120, 91 and 134 kJ∙mol-1; while Q10 values were 3.18, 2.34 and 3.52, respectively.
Influence of High Hydrostatic Pressure on the Capsicum Oleoresin Encapsulated by Globular Protein
Authors: Hong Geun-Pyo , Surassmo Suvimol , Chun Ji-Yeon , Min Sang-Gi , Choi Mi-Jung
Published: June 2012

We studied herein the effects of high hydrostatic pressure on the physical properties of capsicum oleoresin encapsulated with globular protein, such as whey protein isolates (WPI), soybean protein isolates (SPI), and casein protein (CSP). After pressurization at 0.1, 100, 200, and 300 MPa with various concentrations (0.1, 1, 2, and 5 wt%) of proteins, the particle size, ζ-potential, and interface tension were evaluated. Furthermore, the encapsulation efficiency (EE), release study, and morphology were investigated to study the effects of high hydrostatic pressurization upon emulsion stability. While the pressurized emulsion droplet size of capsicum oleoresin emulsion with the protein decreased, the 0.1 wt% concentration of SPI presented the smallest size at 257.37 nm. The interface tension of all protein emulsions decreased slightly after high-pressure treatment according to the increment of the pressure level. EE (%) of the WPI, SPI, and CSP emulsions increased when the pressure level increased. The lowest EE 48.91% was presented in pressurized WPI emulsion at 0.1 MPa while CSP emulsion at 300 MPa showed the highest EE about 65.76%. Over twelve hours, the core material of the pressurized protein emulsions was released slowly compared to non-pressurized conditions with the WPI and CSP emulsions. At the end of the storage of the WPI and CSP non-pressured emulsions, the remaining amount of encapsulated capsicum oleoresin was only 10% and 40%, respectively, less than emulsions treated under high pressurization. Thus, the high pressurized protein could be a candidate for the encapsulation of the capsicum oleoresin.
Selected Some Engineering Properties of Peanut and Its Kernel
Authors: Dilmac Mesut , Altuntas Ebubekir
Published: June 2012

Selected some engineering (geometric, volumetric and frictional) properties of peanut (Arachis hypogaea L.) and its kernel were determined at a moisture content of 8.25% and 10.03% (dry basis), respectively. The mean values of length, width, thickness and geometric mean diameter were 40.73 mm, 17.52 mm , 15.61 mm, 22.46 mm for peanut, and 21.08 mm, 10.22 mm, 10.89 mm, 13.22 mm for its kernel, respectively. The sphericity, bulk and true densities, angle of repose, porosity, surface area, mass and volume values were obtained for peanut and its kernel, respectively. The mean values of static and dynamic coefficient of friction against galvanized steel, chipboard and plywood surfaces were determined. The maximum static and dynamic coefficients of friction were found for plywood and galvanized steel surfaces for peanut and its kernel, respectively.
Delayed modifications in plant-water relations in the coastal marsh halophyte Spartina patens following sudden increases in soil salinity
Authors: Salpeter Kara E. , Millemann Daniel R. , Caputo Michael F. , White Brittany L. , Touchette Brant W.
Published: June 2012

Little is known about how upper marsh plants (growing in freshwater) will respond physiologically to sudden increases in salinity. In this study, we used experimental microcosms to evaluate changes in plant-water relations in the halophyte Spartina patens following increases in soil salinity (salinity levels: 15, 30, and 45). There was a delay (by 3–5 weeks) in the lowering of leaf water potential (ψleaf), stomatal conductance (g), and tissue water content (θ) in plants subjected to salinities of 30–45. These physiological delays in plant-water adjustments following sudden increases in salinity may be an adaptation of S. patens that allows it to effectively exploit higher habitat elevations that receive intermittent seawater inundations without promoting costly physiological modifications.
Culture medium optimization and lipid profiling of Cylindrotheca, a lipid- and polyunsaturated fatty acid-rich pennate diatom and potential source of eicosapentaenoic acid
Authors: Suman Keerthi , Kiran Thomas , Devi Uma Koduru , Sarma Nittala S.
Published: June 2012

Cylindrotheca, an epipelic benthic pennate diatom, holds promise as a nutraceutical source and may be useful for aquaculture. Experiments were done on two Cylindrotheca species, Cylindrotheca fusiformis (UTEX 2084) and C. closterium, which was isolated from seawater collected offshore from Visakhapatnam, India. C. closteriumwas identified through microscopy and rDNA typing. Type and concentration of nutrient components in the culture medium that promoted best growth and highest lipid accumulation were identified. Lipid content was gravimetrically estimated. For relative comparison of the effects of different culture media on lipid content, we made estimations through rapid in situ screening method using Nile red staining and spectrofluori\xadmetry. The fatty acid profile of lipid was obtained through gas chromatography-mass spectroscopy. Nualgi, a commercially available micronutrient ready-mix with elements adsorbed as nanoparticles on a modified silica sol, was found to significantly boost growth in both Cylindrotheca species when used in lieu of a conventional micronutrient mix prepared from eight compounds. Among the three nitrogen sources tested – sodium nitrate (NaNO3), urea, and ammonium chloride (NH4Cl) – best growth of C. fusiformis occurred on nitrate and urea, while NH4Cl was best for C. closterium. Lipid productivity was much higher in cultures supplied with NH4Cl for both Cylindrotheca species and compensated for lower biomass in C. fusiformis. Mixotrophy with glycerol or sodium acetate resulted in no significant increase in growth over photoautotrophy. Both Cylindrotheca species were lipid rich; lipid constituted 18–27% of dry biomass in the medium with NaNO3. Among total fatty acids, polyunsaturated fatty acids constituted <40%, eicosapentaenoic acid 25%, and arachidonic acid ∼8% and ∼4% in C. fusiformis and C. closterium, respectively. NH4Cl, phosphate, and Nualgi micronutrient ready-mix in concentrations optimal for each strain contribute to a good culture medium for Cylindrotheca.
Fucoid assemblages on the north coast of Spain: past and present (1977–2007)
Authors: Lamela-Silvarrey Cristina , Fernández Consolación , Anadón Ricardo , Arrontes Julio
Published: June 2012

Fucoid assemblages dominated by Pelvetia canaliculata, Fucus spiralis, F. vesiculosus, and Ascophyllum nodosum located at two sites on the central coast of Asturias (northern Spain) were sampled monthly in 1977. Repeating the same sampling methodology, a resurvey was done in 2007 to detect changes in the abundances of the species using the previous data as a baseline. Annual net primary production was lower for all the species in 2007, and there were differences in the timing of maximum biomass for P. canaliculata and F. vesiculosus, as well as a shortening of the growth period in 2007. Associated fauna also differed between dates. Higher abundances of Gibbula spp. occurred in 2007, whereas littorinid species densities in the upper intertidal were reduced in that year. As a result, the fucoid-grazers balance changed, with P. canaliculata and particularly F. vesiculosus, being the assemblages most sensitive to change. Observed modifications were not merely fluctuations in the biomass patterns of these species, but also responses to increases in air temperature and sea surface temperature and to a shift in the frequency and seasonality of upwelling episodes. Other long-term abiotic fluctuations not directly related to global warming should also be considered as possible drivers for these changes.
Seasonal periodicity and reproduction of brown algae (Phaeophyceae) at Puerto Deseado (Patagonia)
Authors: Asensi Aldo O. , Küpper Frithjof C.
Published: June 2012

Puerto Deseado is a locality on the Atlantic coast of Patagonia (47°45′ S, 65°54′ W) with a ria (fjord-like estuary) several kilometres long that follows the course of Rio Deseado. From 1969 to 1972, we followed the development of 50 species of mostly intertidal brown macroalgae at five sites, one outside the ria and four within. Collections and observations were made at least once monthly to determine species identities, vegetative and reproductive states of the thalli, and variations between the different sites. Several environmental factors were used to describe the sites, including seawater temperature, season, and hydrodynamics. In summer, there were more species, coincident with the highest proportion of plurilocular sporangia. In contrast, unilocular sporangia appeared mostly in autumn. The difference between the five sites was well defined: nine species from the outermost site did not occur inside the ria, and only 13 species were found at all five sites. The number of species gradually declined towards the interior of the ria. The aim of this study was to document brown algal vegetation at the beginning of the 1970s to provide a baseline dataset before the start up of large-scale port activity.
The marine halophytes Carpobrotus edulis L. and Arthrocnemum macrostachyum L. are potential sources of nutritionally important PUFAs and metabolites with antioxidant, metal chelating and anticholinesterase inhibitory activities
Authors: Custódio Luísa , Ferreira Ana Catarina , Pereira Hugo , Silvestre Laura , Vizetto-Duarte Catarina , Barreira Luísa , Rauter Amélia Pilar , Alberício Fernando , Varela João
Published: June 2012

We report antioxidant, metal chelating and anticholinesterase activities of methanol extracts from two edible halophytes, Carpobrotus edulis and Arthrocnemum macrostachyum. We also report a preliminary chemical screening, total contents of phenolic compounds in the extracts and the fatty acid profiles of both species. Arthrocnemum macrostachyum is a potential source of metabolites with free radical scavenging, iron (Fe3+) reducing and copper (Cu2+) chelating activities; it had a high concentration of polyunsaturated fatty acids (46.5%), mainly α-linolenic and linoleic acids. Carpobrotus edulis had dual anti-cholinesterase activity against both acetylcholinesterase and butyrylcholinesterase. Both species had a high content of phenolic compounds. Arthrocnemum macrostachyum is a potential biological source of biochemicals counteracting free radical-induced oxidative damage and also degenerative diseases associated with metabolic stress, such as cancer and neurological disorders. Carpobrotus edulis is a candidate species for future studies on novel and alternative therapies for the treatment of neurological disorders associated with low levels of acetylcholine in the brain.
New record of Sargassum denticarpum Ajisaka (Fucales, Phaeophyceae) from Iriomote Island (Ryukyu Archipelago, Japan)
Authors: Shimabukuro Hiromori , Kawane Masako , Hamaguchi Masami
Published: June 2012

The brown macroalgal genus Sargassum forms beds around the Japanese coast; these beds are important for marine ecosystem functioning and fisheries. In recent years, a northward shift in the distribution patterns of southern Sargassum spp. has been postulated as a result of warming in the western Pacific. To examine this theory, we surveyed species richness and diversity of genus Sargassum algae around the Ryukyu Islands, Japan, which is the northern limit of selected Sargassum species native to tropical and subtropical regions. We collected from Iriomote Island (Ryukyu Archipelago) specimens of a species resembling Sargassum denticarpum, which is endemic to Vietnam. The specimens had the following morphological characteristics in common with S. denticarpum: (1) terete or slightly compressed primary branches, (2) simple lanceolate primary and lateral leaves with dentate margins in all stages, (3) spherical-to-elliptical vesicles with or without spines and wings, (4) monoecious, and (5) compressed receptacles with spines on the margins. In addition, internal transcribed spacer 2 (ITS2) sequences of the Ryukyu specimens and of S. denticarpum collected in Vietnam clearly showed that the two are closely related. On the basis of these morphological and molecular characteristics, we present the first report of S. denticarpum in Japan.
Contribution of 3D power Doppler ultrasound to the evaluation of placental circulation in normal pregnancies and pregnancies complicated by preeclampsia
Authors: Mihu Carmen Mihaela , Drugan Tudor , Mihu Dan
Published: June 2012

Aim: This study assesses the value of intraplacental vascularization indices, determined by three-dimensional (3D) power Doppler ultrasound, in the evaluation of placental circulation. A prospective study has been conducted on two groups of pregnant women. Group I included pregnant women with a normal evolution of the pregnancy, whereas group II consisted of pregnant women with preeclampsia. The subjects were assessed by ultrasound between the 28th and 38th week of amenorrhea. Intraplacental vascularization was studied by 3D and Doppler ultrasound. Intraplacental vascularization indices were calculated using the VOCAL program, whereas statistical processing was completed using descriptive and comparative statistical methods.

Results: The values of the three intraplacental vascularization indices were lower in the group of pregnancies with preeclampsia compared with the group with normal pregnancies. In normal pregnancies, the evolution of umbilical resistivity index (RI) values was statistically proven to be significantly correlated with the values of intraplacental vascularization indices. In the case of pathological pregnancies, RI values could be maintained within normal limits, whereas vascularization, flow, and vascularization-flow index values decreased significantly compared with the group of normal pregnancies.

Conclusions: The determination of intraplacental vascularization indices can play an important role in the monitoring of placental circulation in pregnancies with a normal evolution and those with preeclampsia.
An open-label, randomized efficacy and safety trial of subcutaneous and intramuscular BT088 (Fovepta) human hepatitis B immunoglobulin in neonates of HBV-carrier mothers
Authors: Buxmann Horst , Kamin Wolfgang , Kriván Gergely , Siklós Pál , Mendling Werner , Wartenberg-Demand Andrea , Wolf Daniele M. , Schlösser Rolf L.
Published: June 2012

Objective: The objective of the study was to assess the efficacy and safety of subcutaneously (SC) and intramuscularly (IM) administered BT088 (Fovepta) human hepatitis B immunoglobulin in neonates of hepatitis B surface antigen (HBs/HBsAg)-positive mothers in the prevention of hepatitis B infection.

Methods: This was an open, prospective, multicenter trial, in which infants were randomized to receive a single SC or IM dose of BT088 (200 IU, 0.4 mL) within 12 h of birth simultaneously with active vaccination against hepatitis B. The primary efficacy variable was the response rate, defined as the proportion of infants whose anti-HBs concentration was negative at predose and ≥100 IU/L 48 to 72 h postdose.

Results: The full analysis set included 31 neonates (17 SC and 14 IM). Response was experienced by 30 (96.8%) of 31 infants who received BT088 by either route of administration. The median postdose anti-HBs concentration was 261.2 IU/L. One neonate had a postdose anti-HBs level lower than 100 IU/L (81.0 IU/L). No infant experienced seroconversion during the 7- to 15-month follow-up. BT088 was well tolerated, with no allergic-like, or injection-site reactions observed.

Conclusion: SC and IM administration of 200 IU (0.4 mL) BT088 resulted in protective serum anti-HBs titers within 72 h of administration in newborn infants and was well tolerated and effective.
Bishop score and cervical length at 33–35 weeks of gestation and the risk of intrapartum cesarean delivery of twins
Authors: Park Kyo Hoon , Lee Sung Youn , Jeong Eun Ha , Ryu Aeli , Oh Kyung Joon , Kim Shi Nae
Published: June 2012

Aim: The aim of this study is to determine the association between Bishop score and cervical length measured at 33–35 weeks of gestation and the intrapartum risk of cesarean delivery of twins.

Methods: This prospective observational study recruited women with vertex/vertex twin gestations at 33–35 weeks of gestation. Determination of the Bishop score and ultrasound measurement of the cervical length were performed. A regression model was constructed with control for known intrapartum and postpartum confounders.

Results: One hundred and forty-six women were analyzed; 18 women (12.3%) had cesarean deliveries during labor. Based on univariate nalysis, the Bishop score at 33–35 weeks was significantly associated with the risk of intrapartum cesarean delivery of twins, whereas cervical length, maternal age, height, and weight at 33–35 weeks were not associated. Multivariate logistic regression analysis identified induction of labor and birth weight of the first-born twin, but not Bishop score, as independent predictors of intrapartum cesarean delivery of twins.

Conclusions: A low Bishop score at 33–35 weeks of gestation was associated with an increased risk of intrapartum cesarean delivery of twin gestations. However, this relationship disappeared after adjusting for relevant intrapartum or postpartum confounders. Only labor induction and high birth weight of the first-born twin were independently associated with an increased risk of cesarean delivery in labor.
An evolutionary test of the isoform switching hypothesis of functional progesterone withdrawal for parturition: humans have a weaker repressive effect of PR-A than mice
Authors: Wagner Günter P. , Tong Yingchun , Emera Deena , Romero Roberto
Published: June 2012

Background: A decrease in maternal serum progesterone (P4) concentrations precedes the onset of labor in most placental mammals. Humans differ by maintaining high levels of P4 throughout birth. Parturition in humans probably includes mechanisms that undercut the pregnancy sustaining function of P4. One attractive hypothesis is the isoform switching hypothesis (ISH). ISH is supported by in vitro evidence that progesterone receptor isoform A (PR-A) inhibits PR-B and that the PR-A/PR-B ratio increases towards term.

Materials and methods: Here, we test the hypothesis that isoform switching is an adaptation to high levels of P4 at term, predicting that, in humans, PR-A mediated repression of PR-B is stronger than in mouse. We use reporter assays with human and mouse PRs to detect species differences in the repressive effects of PR-A.

Results: We found that human PR-B is less sensitive to repression by human PR-A than mouse PR-B, contrary to our prediction. The difference between human and mouse PR-B sensitivity is most pronounced at PR-A/PR-B ratios typical for the preterm myometrium.

Conclusions: Our results are inconsistent with the ISH. We speculate that, instead, the lower sensitivity of human PR-B to PR-A may be relevant for the maintenance of pregnancy at high progesterone levels and increasing PR-A concentrations towards term.
Oxidative stress stimulates α-tocopherol transfer protein in human trophoblast tumor cells BeWo
Authors: Etzl Ronny P. , Vrekoussis Thomas , Kuhn Christina , Schulze Sandra , Pöschl Johannes M. , Makrigiannakis Antonis , Jeschke Udo , Rotzoll Daisy E.
Published: June 2012

α-Tocopherol transfer protein (α-TTP) has been identified as the major intracellular transport protein for the antioxidant vitamin E (α-tocopherol). Expression of α-TTP on the reproductive system has been described both in mouse uterus and lately in the human placenta. The aim of this study was to clarify if placental expression of α-TTP can be modified by substances causing oxidative reactions. The human choriocarcinoma cell line BeWo was, therefore, treated with two known pro-oxidants. α-TTP expression was determined with immunocytochemistry and evaluated by applying a semiquantitative score. The presence of pro-oxidants in BeWo cells induced α-TTP expression. We thus hypothesize that stimulation of α-TTP expression by oxidative stress, as this was induced by pro-oxidants, could be part of an antioxidant process occurring in the placenta in the aim of enhancing the supply of α-tocopherol. This process could occur both in normal pregnancies, as well as in pregnancy disorders presented with intensified oxidative stress. In that view, this model is proposed for further oxidative stress studies on trophoblast and placenta, on the grounds of clarifying the role of α-tocopherol in pregnancy physiology and pathophysiology.
Forced vibration of delaminated Timoshenko beams subjected to a moving load
Authors: Kargarnovin Mohammad H. , Ahmadian Mohammad T. , Jafari-Talookolaeia Ramazan Ali
Published: June 2012

A composite beam with single delamination under the action of moving load has been modeled accounting for the Poisson’s effect, shear deformation, and rotary inertia. The existence of the delamination changes the stiffness of the structure, and this affects the dynamic response of the structure. We have used a constrained mode to simulate the behavior between the delaminated surfaces. Based on this mode, eigensolution technique is used to obtain the natural frequencies and their corresponding mode shapes for the delaminated beam. Then, the Ritz method is adopted to derive the dynamic response of the beam subjected to a moving load. The obtained results for the free and forced vibrations of beams are verified against reported similar results in the literature. Moreover, the maximum dynamic response of such beam is compared with an intact beam. The effects of different parameters such as the size, depth, and spanwise location of the delamination, the load velocity, the different ply configurations, and the Poisson’s effect on the dynamic response of the beam are studied.
Determination of displacement and failure loads formed in reinforced concrete construction with overhang and without overhang by ANN modeling
Authors: Donduren Mahmud Sami
Published: June 2012

Determination of fracture load and displacement values that might be formed in a reinforced concrete (RC) construction having different overhang types by artificial neural network (ANN) modeling was investigated in this study. Nonlinear static pushover analysis of the key parameters in change defined in Turkish earthquake code (TEC) [1] for columns and beams was carried out, and the capacity curves, failure loads, and displacements were obtained. In total, 64 RC buildings were analyzed according to the change intervals of the parameters chosen. In addition, regression analysis was performed with Statistical Packages for the Social Sciences (SPSS) statistical program (SPSS Inc., Chicago, IL, USA) by using the same parameters for the same model types. Consequently, separate equations were obtained for displacement and load values, and their R2 values were calculated. As a result of ANN modeling, 91.77% convergence for displacement values and 90.61% convergence for load values were obtained. The graphs between the calculated values and expected values are given.
Failure assessment of a woven E-glass/vinyl ester composite subjected to large deformation loading
Authors: Hufner David R. , Xing Liqun , Accorsi Michael L.
Published: June 2012

Woven polymer-based composites exhibit highly non-linear behavior, which often results in very high strains to failure. A micromechanical model is developed to represent the large deformation kinematics of woven composites, and develop predictions for failure strain components in specific cases of multiaxial loading. Failure functions are proposed for macromechanical analyses of arbitrary cases of large deformation loading. The approach is validated against basic tension experiments performed using both digital image correlation and with specially designed instrumentation for large strain measurement. Predicted failure strains correspond well with experimental observations. The proposed failure functions are well suited for finite element applications involving user-defined material models.
Quantitative evaluation of mineral admixtures on the properties, pore structure, and durability of cement-based composites
Authors: Lee Chinlai , Chi Maochieh , Huang Ran
Published: June 2012

The influence of water/cementitious material ratio, silica fume, and fly ash as partial Portland cement replacement materials on the properties, pore structure, and durability of cement-based composites was evaluated by conducting compressive strength test, mercury intrusion porosimetry test, water absorption, rapid chloride penetration test, and scanning electron microscopy (SEM). Water/cementitious material ratio, and replacement percentage of silica fume and fly ash have significant effects on the pore structure and durability of cement-based composites. Composites with silica fume or fly ash have a denser structure than the control composite on SEM micrographs. Silica fume has about 5–10 times as much effect as fly ash, according to results of multiple linear regression analyses of testing data.
Buckling behaviour of cross-ply laminated plates by a higher-order shear deformation theory
Authors: Neves Ana M.A. , Ferreira António J.M. , Carrera Erasmo , Cinefra Maria , Roque Carla M.C. , Jorge Renato M.N. , Soares Cristóvăo M.M.
Published: June 2012

In this article, Carrera’s Unified Formulation (CUF) is combined with a radial basis function collocation technique. A higher-order theory that considers deformations in the thickness direction was developed under CUF to predict the buckling behaviour of laminated plates. The obtained governing equations and boundary conditions are then interpolated by collocation with radial basis functions. The accuracy and efficiency of the combination of the two techniques for buckling problems of laminated plates are demonstrated through numerical experiments.
Fabrication and characterization of hydroxyapatite/collagen bone-like nanocomposite through a self-assembly method
Authors: Wang Zhenlin , Yan Yuhua , Wan Tao
Published: June 2012

Based on a self-assembly mechanism, a co-precipitation method was utilized to fabricate bone-like biomimetic nanocomposite with a simplified preparation approach and accessible materials to investigate in depth some characteristics of hydroxyapatite/collagen(HAp/Col) nanocomposite for the elucidation of performances in some respects. The as-prepared composite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transformation infrared spectroscopy, and thermal analysis. The results show that HAp nanocrystals formed as preferentially oriented slender needles 50–100 nm in length on a felt-like Col matrix which is composed of large numbers of randomly oriented Col fibers and showed polycrystalline behavior. The as-prepared cellular composites are analogous in both composition and nanostructured architecture to native bone, longer aging time promotes the growth and purification of nano-HAp on Col, and characterization confirms that chemical interaction occurs and causes intimate bonding between HAp and Col.
Psychometric performance of the CushingQoL questionnaire in conditions of real clinical practice
Authors: Santos Alicia , Resmini Eugenia , Martínez-Momblán Ma Antonia , Crespo Iris , Valassi Elena , Roset Montserrat , Badia Xavier , Webb Susan M
Published: June 2012

Objective

To evaluate health-related quality of life (HRQoL) in Cushing's syndrome (CS) with the disease-generated CushingQoL questionnaire and to confirm its psychometric properties of test–retest reliability and sensitivity to change.

Design

Clinical practice conditions in a tertiary referral center.

Methods

The CushingQoL and EuroQoL questionnaires were administered at baseline and during follow-up and correlated with clinical parameters in 59 patients with CS. To check test–retest reliability, stable patients (either biochemically cured or with active hypercortisolism) were evaluated twice. To investigate sensitivity to change, new patients were evaluated at diagnosis and twice more following improvement after successful surgery.

Results

At baseline, patients with active disease scored lower (indicating worse HRQoL) than those cured on the CushingQoL (46±14 vs 58±20,P<0.05) but not on the EuroQoL-visual analog scale (VAS; 64±20 vs 70±16,PNS). Test–retest reliability of CushingQoL was confirmed in stable patients, both in the ‘cured group’ (intraclass correlation coefficient (ICC)=0.78,n=34) and in the ‘active group’ (ICC=0.66,n=14). Sensitivity to change was confirmed in the ‘improvement group’ (n=11), as the CushingQoL score increased 4±1.5 and 9±3 months after surgery (P<0.01 and <0.001 respectively); the EuroQoL-VAS only improved after 9±3 months (P<0.01). Effect sizes were 1.02 and 1.86 for CushingQoL at 4±1.5 and 9±3 months respectively. Finally, scores of both questionnaires were correlated (r=0.504;P<0.001).

Conclusions

The CushingQoL questionnaire shows good test–retest reliability and sensitivity to change in clinical practice conditions.
Material considerations for optical interfacing to the nervous system
Authors: Chernov Mykyta M. , Duke Austin R. , Cayce Jonathan M. , Crowder Spencer W. , Sung Hak-Joon , Jansen E. Duco
Published: June 2012

Optical neural interfaces offer several advantages over electrophysiological methods in both clinical and experimental applications. Optical stimulation techniques exhibit high spatial selectivity, do not create electrical artifacts, and allow for stimulation of specific neuronal populations. Calcium- and voltage-sensitive dyes can probe neuronal and astrocytic signaling at both single cell and network scales, and miniature optical sensors can measure a variety of physiological signalsin situ. However, optical neural interfaces must be robust, safe, and effective over long periods of time in order to be acceptable for use in human patients. In this article, we draw the attention of the materials science community to the need for a new generation of materials that have the necessary optical performance and, at the same time, conform to the constraints placed on implanted devices in terms of size, relevant mechanical properties, and biocompatibility, providing some examples of recent advancements in the field.