bluuebunny/crossref_metadata_2025 huggingface dataset:
A content analysis of advertisements related to oral health in children’s Tamil television channels – a preliminary report
Authors: SUKUMARAN APARNA , DIWAKAR MADANKUMAR P. , SHASTRY SHIVAKUMAR M.
Published: October 2011

International Journal of Paediatric Dentistry 2012; 22: 232–238

Aims.  This study was conducted to examine the nature, content, and duration of advertisements broadcasted during children’s Tamil television channels and to determine the extent to which television advertising changes during school holiday and non‐holiday periods and between prime time and non‐prime time broadcast.

Methods.  Television broadcasts on two main children’s Tamil television channels were video‐recorded over 16 days between 17.00–19.00 hours (non‐prime time) and 19.00–21.00 hours (prime time). For each commercial, the type of product advertised, as well as the duration (in seconds), was recorded. Advertisements were categorized as ‘food’ and ‘non‐food’. The former category was further subdivided into ‘sugar‐rich foods’ and ‘other foods’. The sugar‐rich foods were further categorized as liquid, solid and sticky, and slowly dissolving sugars. Commercials related to the promotion of oral health products and non‐food products were also recorded.

Results.  Among the total of 128 h of television programmes recorded, advertising accounted for 10.15% (13.01 hours). The advertisement of sugar‐rich food products, non‐food and oral hygiene products occupied 50.36%, 38.41% and 1.90%, respectively, of the total advertising time. Solid and sticky products made up 100% of advertisements in this category on Chithiram television channel, compared with 62.5% of advertisements on Chutti television channel.

Conclusion.  It was concluded that the advertising of sugar‐rich foods, particularly solid and sticky food products, was broadcasted more in Chithiram television channel, during school holidays and during prime time.
Health‐related quality of life in subjects with and without Type 2 diabetes: pooled analysis of five population‐based surveys in Germany
Authors: Schunk M. , Reitmeir P. , Schipf S. , Völzke H. , Meisinger C. , Thorand B. , Kluttig A. , Greiser K.‐H. , Berger K. , Müller G. , Ellert U. , Neuhauser H. , Tamayo T. , Rathmann W. , Holle R.
Published: October 2011

Diabet. Med. 29, 646–653 (2012)

Aims  To estimate population values of health‐related quality of life (HRQL) in subjects with and without Type 2 diabetes mellitus across several large population‐based survey studies in Germany. Systematic differences in relation to age and sex were of particular interest.

Methods  Individual data from four population‐based studies from different regions throughout Germany and the nationwide German National Health Interview and Examination Survey (GNHIES98) were included in a pooled analysis of primary data (N = 9579). HRQL was assessed using the generic index instrument SF‐36 (36‐item Short Form Health Survey) or its shorter version, the SF‐12 (12 items). Regression analysis was carried out to examine the association between Type 2 diabetes and the two component scores derived from the SF‐36/SF‐12, the physical component summary score (PCS‐12) and the mental component summary score (MCS‐12), as well as interaction effects with age and sex.

Results  The PCS‐12 differed significantly by −4.1 points in subjects with Type 2 diabetes in comparison with subjects without Type 2 diabetes. Type 2 diabetes was associated with significantly lower MCS‐12 in women only. Higher age was associated with lower PCS‐12, but with an increase in MCS‐12, for subjects with and without Type 2 diabetes.

Conclusions  Pooled analysis of population‐based primary data offers HRQL values for subjects with Type 2 diabetes in Germany, stratified by age and sex. Type 2 diabetes has negative consequences for HRQL, particularly for women. This underlines the burden of disease and the importance of diabetes prevention. Factors that disadvantage women with Type 2 diabetes need to be researched more thoroughly.
Another View from the Ground: How Laws Like SB1070 and HB2281 Erode the Intergroup Fabric of Our Community
Authors: Bean Meghan G. , Stone Jeff
Published: October 2011

In this commentary, we discuss the articles included in ASAP's special issue on Arizona's Senate Bill 1070 and explore the means by which intergroup bias related to the support and implementation of this law may be reduced. Specifically, we briefly discuss the overall conclusions that can be drawn from the articles included in this volume and address questions that still remain regarding the potential effects of this law. Next, we explore potential strategies for reducing bias between Whites and Latinos, and we discuss the limitations Arizona's House Bill 2281 will impose on our ability to successfully improve intergroup relations in Arizona.
Utilization Survey of a Rural Creek Fishery in Central Alabama
Authors: Ebert Ellen S. , Wilson Natalie , Wacksman Mitch , Loper John R. , Schell John D. , Fowler Alan
Published: October 2011

A one‐year angler intercept survey was conducted on Choccolocco Creek, a rural, limited access tributary to the Coosa River in northeastern Alabama. The purpose of the survey was to collect data and information about the behaviors and fish consumption habits of the recreational anglers who fish there. Nine survey locations were included in the stratified sampling plan, and sampling occurred throughout daylight hours, on weekdays and weekends/holidays, during all four seasons of the year. Surveys were completed on a total of 101 survey days between June 28, 2008 and June 27, 2009.6 Seventy‐two anglers were observed fishing during the survey period, and 52 (72%) of those individuals agreed to participate in the survey. Based on the information collected by the survey clerks, the angler population fishes the Creek between 1 and 54 times per year, with an average frequency of seven trips per year. The average number of months fished was three months per year, with a range of one to nine months. Only 15% of the anglers who participated in the survey (eight individuals) had succeeded in catching fish by the end of their trips, and only four of those individuals (8%) had retained any of the fish they had caught for consumption. Reasons provided for not retaining fish were that they either only fished for sport, did not catch enough fish to eat, or the fish they caught were too small to keep. Because so few anglers used and harvested fish from the resource, fish consumption rates could not be determined with a high degree of confidence. However, from these limited data it was estimated that the three anglers for whom consumption rates could be estimated had annualized average daily fish consumption rates of 0.14, 0.44, and 7.9 grams per day (g/day). The majority of anglers traveled less than 10 miles to fish the Creek. It was estimated that a total population of 173 anglers use the Creek each year. The results of this survey indicated that Choccolocco Creek is a local fishery that is not heavily used by area residents.
Foodborne Exposure to Pesticides and Methylmercury in the United Arab Emirates
Authors: Davidson Christopher A. , Krometis Leigh‐Anne H. , Al‐Harthi Suaad S. , Gibson Jacqueline MacDonald
Published: October 2011

As part of a comprehensive environmental health strategic planning project initiated by the government of Abu Dhabi, we assessed potential dietary exposure in the United Arab Emirates (UAE) to methylmercury (in seafood) and pesticides (in fruits and vegetables) above international guideline levels. We present results for the UAE population by age, gender, and body mass index. Our results show very low daily risks of exposure to pesticides in fruits and vegetables at levels exceeding WHO guidelines even under the conservative assumption that no pesticides are removed during washing and food preparation. Thus, exposure to pesticides on fruits and vegetables does not appear to be a major public health concern in the UAE. The chances of exposure to methylmercury in seafood are much higher; our model estimates a mean 1 in 5 daily risk of exceeding the FAO/WHO provisional tolerable weekly intake. However, great caution should be used in interpreting these results, as we analyzed only the risks and not the substantial benefits of fish consumption. In fact, previous studies have demonstrated that exposure to the n‐3 polyunsaturated fatty acids in fish can increase IQ in developing children, and it can substantially decrease the risk in adults of coronary heart disease and stroke. Further research is warranted to compare the risk of Me‐Hg exposure from fish to the nutritional benefits of fish consumption in the UAE and to determine appropriate methods to communicate risk and benefit information to the UAE population.
The Federal Reserve and the 2007–2009 Financial Crisis: Treating a Virus with Antibiotics? Evidence from the Commercial Paper Market
Authors: Griffiths Mark D. , Kotomin Vladimir , Winters Drew B.
Published: October 2011

The two main explanations for the crisis in the commercial paper (CP) market are credit concerns and liquidity issues. The CP market is not homogeneous in terms of credit quality, maturities and types of issues. We find that lower credit‐quality CP suffered more during the crisis. Additionally, we find little evidence that Federal Reserve (Fed) liquidity facilities reduced the impact of the crisis, but that when the Fed became a lender in the CP market, the crisis pressures were dramatically reduced. We conclude that the crisis in the money markets is related more to increases in credit risk. Liquidity is a secondary issue.
Tax Calendar Effects in the Municipal Bond Market: Tax‐Loss Selling and Cherry Picking by Investors and Market Timing by Fund Managers
Authors: Chen Haiwei , Estes Jim , Ngo Thanh
Published: October 2011

Examining municipal bond returns, bond fund flows and buying activities by fund managers over the period 1990–2009, we find evidence of tax calendar‐related rational opportunistic trading patterns by fund investors and fund managers. Specifically, fund shareholders conduct tax‐loss selling in December and re‐invest in January. In April, June, and September, fund investors rationally cherry pick to sell their shares of short‐term bond funds instead of their shares of long‐term bond funds to raise cash to pay estimated taxes. Unlike fund shareholders, fund managers adopt a contrarian strategy of buying in December and selling in January.
Recombinant BCG coexpressing Ag85B, CFP10, and interleukin‐12 induces multifunctional Th1 and memory T cells in mice
Authors: LIN CHIH‐WEI , SU IH‐JEN , CHANG JIA‐RU , CHEN YIH‐YUAN , LU JANG‐JIH , DOU HORNG‐YUNN
Published: October 2011

Lin C‐W, Su I‐J, Chang J‐R, Chen Y‐Y, Lu J‐J, Dou H‐Y. Recombinant BCG coexpressing Ag85B, CFP10, and interleukin‐12 induces multifunctional Th1 and memory T cells in mice. APMIS 2012; 120: 72–82.

Mycobacterium tuberculosis (MTB) continues to be a leading cause of human deaths due to an infectious agent. Current efforts are focused on making better TB vaccines. We describe the generation and immunological characterization of recombinant BCG (rBCG). This rBCG was generated by incorporating an expression plasmid encoding two mycobacterial antigens (Ag85B and CFP10) and human interleukin (IL)‐12 into a BCG strain. Immunogenicity studies in mice showed that rBCG coexpressing Ag85B, CFP10, and IL‐12 (rBCG::Ag85B–CFP10–IL‐12) induces a robust immune response in mice. The rBCG vaccine promotes a T‐cell response against MTB that is characterized by a high proportion of polyfunctional and memory T cells in spleen and lung. Our results showed strong immunogenicity and mycobacterial growth inhibition of rBCG::Ag85B–CFP10 plus IL‐12 than that of BCG vaccine.
Role of c‐Jun N‐terminal kinase and p38/activation protein‐1 in interleukin‐1β‐mediated type I collagen synthesis in rat hepatic stellate cells
Authors: ZHANG YAPING , YAO XIXIAN
Published: October 2011

Zhang Y, Yao X. Role of c‐Jun N‐terminal kinase and p38/activation protein‐1 in interleukin‐1β‐mediated type I collagen synthesis in rat hepatic stellate cells. APMIS 2011.

Interleukin‐1 (IL‐1) may play a role in maintaining hepatic stellate cell (HSC) in activated state that is responsible for hepatic fibrogenesis. However, the signal transduction pathway that is stimulated by IL‐1 in HSC remains to be fully elucidated. The aims of this study were to investigate the role of c‐Jun N‐terminal kinase (JNK) and p38/activation protein (AP‐1) in IL‐1β‐mediated type I collagen synthesis in rat HSCs. Here, we show that IL‐1β could activate JNK and p38 in a time‐dependent manner, and that inhibition of the JNK pathway could increase collagen synthesis; however, inhibition of the p38 pathway could inhibit collagen synthesis. Furthermore, IL‐1β activated AP‐1 in a time‐dependent manner in rat HSCs. These data demonstrate that L‐1β could promote the synthesis of type I collagen in rat HSCs, and the JNK and p38/AP‐1 pathways were involved in this process. In summary, IL‐1β‐induced collagen synthesis is possibly mediated by cytoplasmic JNK and p38/AP‐1 pathways. Therefore, drugs that block the p38/AP‐1 pathway may inhibit liver extracellular matrix synthesis and suppress liver fibrosis.
High‐resolution mapping of a novel genetic locus regulating voluntary physical activity in mice
Authors: Yang H. S. , Shimomura K. , Vitaterna M. H. , Turek F. W.
Published: October 2011

Both human beings and animals exhibit substantial inter‐individual variation in voluntary physical activity, and evidence indicates that a significant component of this variation is because of genetic factors. However, little is known of the genetic basis underlying central regulation of voluntary physical activity in mammals. In this study, using an F2 intercross population and interval‐specific congenic strains (ISCS) derived from the C57BL/6J strain and a chromosome 13 substitution strain, C57BL/6J‐Chr13A/J/NA/J, we identified a 3.76‐Mb interval on chromosome 13 containing 25 genes with a significant impact on daily voluntary wheel running activity in mice. Brain expression and polymorphisms between the C57BL/6J and A/J strains were examined to prioritize candidate genes. As the dopaminergic pathway regulates motor movement and motivational behaviors, we tested its function by examining cocaine‐induced locomotor responses in ISCS with different levels of activity. The low‐activity ISCS exhibited a significantly higher response to acute cocaine administration than the high‐activity ISCS. Expression analysis of key dopamine‐related genes (dopamine transporter and D1, D2, D3, D4 and D5 receptors) revealed that expression of D1 receptor was higher in the low‐activity ISCS than in the high‐activity ISCS in both the dorsal striatum and nucleus accumbens. Pathway analysis implicated Tcfap2a, a gene found within the 3.76‐Mb interval, involved in the D1 receptor pathway. Using a luciferase reporter assay, we confirmed that the transcriptional factor, Tcfap2a, regulates the promoter activity of the D1 receptor gene. Thus, Tcfap2a is proposed as a candidate genetic regulator of the level of voluntary physical activity through its influence on a dopaminergic pathway.
Liming induces changes in the macrophyte vegetation of Norwegian softwater lakes by mitigating carbon limitation: results from a field experiment
Authors: Lucassen Esther C.H.E.T. , Smolders Alfons J.P. , Roelofs Jan G.M.
Published: October 2011

Question

Does liming mitigate carbon limitation to the original submerged vegetation of Norwegian softwater lakes?

Location

Dybingsvatn (Dalane region, Southern Norway).

Methods

Eight plots (1 m2) were permanently marked in the deeper part (1.5 m) of the littoral zone of Dybingsvatn in 1994. Half of the plots were limed four times with dolocal (1 kg m−2) in the period 1994–1998. Pore water, surface water chemistry and the occurrence of new plant species were monitored until 2008. In 2008, the composition and cover of the vegetation were estimated and the dominant isoetid plant species were harvested for determination of additional plant characteristics.

Results

Liming lowered the redox potential of the sediment and led to higher concentrations of dissolved inorganic carbon, Ca2+, Mg2+, Fe2+ and Mn2+ in the sediment pore water. Submerged macrophytes that could in some way profit from the higher carbon dioxide concentrations developing in the pore water (e.g. Juncus bulbosus, Sparganium angustifolium and Callitriche hamulata) expanded or colonized the limed plots at different time‐points. Four years of liming did not affect the cover and composition of the original isoetid vegetation, but led to development of taller and heavier plants with higher molar carbon to nitrogen ratios in the shoots, indicating a higher availability and uptake of carbon dioxide from the sediment.

Conclusions

Liming leads to a higher availability of carbon dioxide in the sediment, partly owing to dissolution of carbonates, and partly by inducing anaerobic decomposition of organic matter and the consequent reduction of iron (IIII) hydroxides in the iron‐rich sediment (in‐lake alkalinity generation). All observed changes in the vegetation indicate that liming leads to mitigation of carbon dioxide limitation in Norwegian softwater lakes. Liming may be beneficial for fish populations by reducing concentrations of labile aluminium, but it does not preserve the characteristic chemical sediment properties and original vegetation of softwater lakes. We wish to point out that liming may, in the worst case, lead to an alternative stable lake state with anaerobic sediments as relatively highly productive isoetid plant species have a risk of uprooting.
Addressing social barriers and closing the gender knowledge gap: exposure to road shows is associated with more knowledge and more positive beliefs, attitudes and social norms regarding exclusive breastfeeding in rural Zimbabwe
Authors: Jenkins Alison L. , Tavengwa Naume V. , Chasekwa Bernard , Chatora Kumbirai , Taruberekera Noah , Mushayi Wellington , Madzima Rufaro C. , Mbuya Mduduzi N.N.
Published: October 2011

Exclusive breastfeeding (EBF) is rarely practiced despite its significant child survival benefits. A key constraint to increasing EBF rates in Zimbabwe and most of the developing world is that key decision makers (fathers/partners and other family members) are often poorly informed about EBF and do not attend antenatal clinics where health information is routinely provided. Informed by formative research, a district‐wide campaign was conducted in rural Zimbabwe to encourage EBF and expressing and heat treating (EHT) breast milk as a means to maintain EBF. The campaign combined traditional strategies of education, counselling and outreach through health service delivery with a novel road show ‘edutainment’ intervention to reach men and other community members. A post campaign evaluation measured the association of road show exposure with 20 knowledge items and summative scores of social norms, beliefs and attitudes obtained through exploratory factor analysis. In adjusted models, road show exposure was associated with correct EBF knowledge (β = 1.0, 0.001), EHT knowledge (β = 1.3, P < 0.001) and greater perceived benefits of condom use during pregnancy and breastfeeding (β = 0.5, P < 0.001), and more positive EBF social norms (β = 0.6, P < 0.001), EBF beliefs and attitudes (β = 1.0, P < 0.001) and attitudes towards condom use during breastfeeding (β = 0.6, P < 0.001). Road show exposure was more strongly associated with EBF knowledge among men (P‐value for gender × exposure group interaction = 0.03), suggesting that it also closed the knowledge gap between men and women. Longitudinal studies will determine whether road shows were associated with changes in EBF practices.
Development on drought‐stressed host plants affects life history, flight morphology and reproductive output relative to landscape structure
Authors: Gibbs Melanie , Van Dyck Hans , Breuker Casper J.
Published: October 2011

With global climate change, rainfall is becoming more variable. Predicting the responses of species to changing rainfall levels is difficult because, for example in herbivorous species, these effects may be mediated indirectly through changes in host plant quality. Furthermore, species responses may result from a simultaneous interaction between rainfall levels and other environmental variables such as anthropogenic land use or habitat quality. In this eco‐evolutionary study, we examined how male and female Pararge aegeria (L.) from woodland and agricultural landscape populations were affected by the development on drought‐stressed host plants. Compared with individuals from woodland landscapes, when reared on drought‐stressed plants agricultural individuals had longer development times, reduced survival rates and lower adult body masses. Across both landscape types, growth on drought‐stressed plants resulted in males and females with low forewing aspect ratios and in females with lower wing loading and reduced fecundity. Development on drought‐stressed plants also had a landscape‐specific effect on reproductive output; agricultural females laid eggs that had a significantly lower hatching success. Overall, our results highlight several potential mechanisms by which low water availability, via changes in host plant quality, may differentially influence P. aegeria populations relative to landscape structure.
Need satisfaction, work–school interference and school dropout: An application of self‐determination theory
Authors: Taylor Geneviève , Lekes Natasha , Gagnon Hugo , Kwan Lisa , Koestner Richard
Published: October 2011

Background. In many parts of the world, it is common for secondary school students to be involved in part‐time employment. Research shows that working can have a negative impact on school engagement. However, the majority of studies have focused on the amount of time that students spend working rather than on the quality of work experience and its influence on school engagement.

Aims. This study explored the relation of part‐time work and school experiences to dropout intentions among secondary school and junior college students. The study was conceptualized from a self‐determination theory perspective (Deci & Ryan, 2000).

Sample. Participants were 3,248 students from rural and suburban schools in the greater region of Montreal, Canada.

Method. Questionnaires were used to assess the number of hours worked, the extent to which work interfered with or facilitated school functioning, autonomy, competence, and relatedness experienced in the work and school domains. School performance and school dropout intentions were also assessed.

Results. A curvilinear relation between work hours and dropout intentions was found, reflecting that part‐time work began to be associated with higher dropout intentions only when students worked more than 7 hr per week. Analyses also showed that work–school interference was related to dropout intentions, and that this variable served to mediate the relation of employer autonomy support to dropout intentions.

Conclusions. These results suggest that both the quantity and the quality of students’ part‐time work experiences need to be considered when examining the relation of work to school engagement.
Dioramas as Depictions of Reality and Opportunities for Learning in Biology
Authors: Reiss Michael J. , Tunnicliffe Sue Dale
Published: October 2011

Abstract   A diorama is a careful positioning of a number of museum objects in a naturalistic setting. While expensive to construct, dioramas offer tremendous potential as educational tools. The education literature on dioramas, while growing, is still slight. Here we focus on dioramas as sites for learning science, specifically biology. We examine the extent to which dioramas reflect or construct reality and the effect on visitors. We suggest that a useful perspective can be to see dioramas as telling stories. Visitors respond well to stories and bring their own experiences, hopes, and fears to them. But to maximize the educational impact of dioramas, the stories they tell need to be constructed with some care. Younger visitors, for example, can benefit from scaffolding, an approach often used when introducing children to literature that is at the upper end of, or beyond, their present unaided capabilities.
Digital Storytelling in Museums: Observations and Best Practices
Authors: Wyman Bruce , Smith Scott , Meyers Daniel , Godfrey Michael
Published: October 2011

Abstract The museum landscape has changed dramatically over the last 20 years. Technology has made possible new kinds of interactions, visitor expectations have broadened, competition for time and resources has become increasingly intense, and the buildings serve ever‐more‐complex roles. As a result, interactive designers, including those of us at Second Story, have evolved our skills and approaches to keep pace. This article summarizes many of our observations while sharing some of the best practices that we have evolved to create engaging interactive installations, websites, and experiences. Despite changes in technology and user behavior, a core focus on great storytelling should drive interactive design and serve as the critical element for museums communication and connecting with their visitors.
Multiscale Analysis on Two Dimensional Nanoscale Sliding Contacts of Textured Surfaces
Authors: Tong Ruiting , Liu Geng , Liu Tianxiang
Published: October 2011

Nanoscale sliding contacts are the major factors that influence the friction and result in wear in micro/nanoelectromechanical systems. Many experimental studies indicated that some surface textures could help improve the contact characteristics and reduce friction forces. However, the experimental results may be biased, due to the contamination of the sample surface or substantial defects in the materials. Numerical methods, such as continuum mechanics, meet great challenges when they are applied at length of nanoscale, and the time cost of molecular dynamics (MD) simulation can be extremely high. Therefore, multiscale method, which can capture atomistic behaviors in the region underlying micro/nano physical processes by MD simulations and models other regions by continuum mechanics, offers a great promise. Coupling MD simulation and finite element method, the multiscale method is used to investigate two dimensional nanoscale sliding contacts between a rigid cylindrical tip and an elastic substrate with textured surface, in which adhesive effects are considered. Two series of nanoscale surface textures with different asperity shapes, different asperity heights, and different spacings between asperities are designed. For different heights of asperities or different spacings between asperities, average potential energy, normal forces, mean normal forces, friction forces, and mean friction forces are compared to observe how these parameters influence friction characteristics; then, the optimal asperity height or spacing is discovered. Through the average potential energy, normal forces, mean normal forces, friction forces, and mean friction forces comparisons between smooth surface and textured surfaces, a better shape is advised to indicate that asperity shape plays an important role in friction force reduction. The influences of the indentation depth and radius of the rigid cylindrical tip are analyzed to find out the sensitivity of surface textures to these two parameters. Effects of sliding speed on the characteristics of nanoscale sliding contacts are also discussed. The results show that, with proper asperity height and proper spacing between asperities, surface textures can reduce friction forces effectively. Coefficients of friction (COFs) of all the cases are calculated and compared. Some negative COFs caused by significant adhesive effects are discovered, which are different from traditional macroscopic phenomena.
Detailed State of the Art Review for the Different Online/Inline Oil Analysis Techniques in Context of Wind Turbine Gearboxes
Authors: Hamilton Andrew , Quail Francis
Published: October 2011

The main driver behind developing advanced condition monitoring (CM) systems for the wind energy industry is the delivery of improved asset management regarding the operation and maintenance of the gearbox and other wind turbine components and systems. Current gearbox CM systems mainly detect faults by identifying ferrous materials, water, and air within oil by changes in certain properties such as electrical fields. In order to detect oil degradation and identify particles, more advanced devices are required to allow a better maintenance regime to be established. Current technologies available specifically for this purpose include Fourier transform infrared (FTIR) spectroscopy and ferrography. There are also several technologies that have not yet been or have been recently applied to CM problems. After reviewing the current state of the art, it is recommended that a combination of sensors would be used that analyze different characteristics of the oil. The information individually would not be highly accurate but combined it is fully expected that greater accuracy can be obtained. The technologies that are suitable in terms of cost, size, accuracy, and development are online ferrography, selective fluorescence spectroscopy, scattering measurements, FTIR, photoacoustic spectroscopy, and solid state viscometers.
Cone-partitioned-plate geometry for the ARES rheometer with temperature control
Authors: Snijkers Frank , Vlassopoulos Dimitris
Published: October 2011

A cone-partitioned-plate fixture for the ARES rheometer (TA instruments, DE) has been designed, implemented, and validated. This geometry allows measuring the nonlinear shear flow properties of samples, which display edge fracture in regular cone-and-plate geometries, such as polymer melts and concentrated solutions. Reliable bulk shear flow data can be obtained with these systems at high rates and strains, using very small sample quantities. Measurements can be performed at temperatures ranging from at least − 50 °C up to over 200 °C in a controlled nitrogen environment. An extensive set of start-up shear measurements on moderately entangled linear monodisperse polyisoprene (60 kg/mol) and polystyrene (182 kg/mol) melts to validate the design are presented and discussed with focus on the Cox–Merz rule and the characteristics of the stress overshoot. With this new geometry, the range of artifact-free data is extended by a decade in Weissenberg number (WiD). It is shown that the obtained results compared well with the limited experimental data available from the literature on monodisperse polymer melts. Furthermore, we show that, for the investigated range of WiD in start-up shear, the two monodisperse linear polymers of different chemistry with nearly the same number of entanglements, scale identically.
Effects of weak elasticity on the stability of high Reynolds number co- and counter-rotating Taylor-Couette flows
Authors: Dutcher Cari S. , Muller Susan J.
Published: October 2011

This study examines the impact of dilute polymer solutions on the unique isolated secondary flows between concentric, rotating cylinders, namely Taylor-Couette (TC) flow. We mapped the stability of flow states using Newtonian and dilute polyethylene oxide (PEO) solutions over the Reynolds number range of − 100 < Reo < 500 and 0 < Rei < O(103), where subscripts ‘o’ and ‘i’ refer to outer and inner cylinders, respectively. Elasticity number (El) of the PEO fluids, defined as the ratio of elastic to inertial forces, ranges from O(10− 4) to O(10− 2). This work expands on previous studies by (a) significantly expanding the range of Rei, Reo, and El examined, (b) use of a consistent, conservative protocol for reaching flow states, and (c) rheological characterization of the solutions via shear and capillary breakup extensional rheometry. Using spectral analysis of flow visualization of the r-z or z-θ planes, we find the effect of El on the critical conditions for laminar and chaotic axisymmetric and nonaxisymmetric flow states is nonmonotonic and mode-dependent, with greater modification of higher order transitions involving small-scale features. While the critical conditions are modified by low El for all transitions, the flow states vary from those for Newtonian fluids at higher Rei and for the more elastic fluids.
Evaluation of molecular linear viscoelastic models for polydisperse H polybutadienes
Authors: Li Si Wan , Park Heon E. , Dealy John M.
Published: October 2011

Two tube-based molecular models, the hierarchical 3.0 model and the branch-on-branch model were evaluated for their abilities to predict the behavior of a series of polydisperse, H-shaped, 1,4-polybutadienes. The samples had been synthesized using a novel technique designed to suppress the generation of high molar mass by-products. While size exclusion chromatography data indicated that the samples were monodisperse, low molar mass by-products were later revealed by temperature gradient interaction chromatography. Viscoelastic data were obtained at temperatures ranging from −75 °C to 25 °C, and the samples were found to be thermorheologically simple. Sensitivity and uncertainty analyses revealed that among the model parameters, the value of plateau modulus has the strongest effect on model predictions. As molecular models improve, it will become ever more essential to evaluate them using accurate data on materials whose microstructures have been reliably established. This is especially important for materials that are structurally polydisperse.
Cardiotrophin-1 Promotes a High Survival Rate in Rabbits with Lethal Fulminant Hepatitis of Viral Origin
Authors: Tuñon Maria Jesus , San Miguel Beatriz , Crespo Irene , Riezu-Boj Jose Ignacio , Larrea Esther , Álvarez Marcelino , González Iranzu , Bustos Matilde , González-Gallego Javier , Prieto Jesus
Published: October 2011

Rabbit hemorrhagic disease virus (RHDV) causes lethal fulminant hepatitis closely resembling acute liver failure (ALF) in humans. In this study, we investigated whether cardiotrophin-1 (CT-1), a cytokine with hepatoprotective properties, could attenuate liver damage and prolong survival in virus-induced ALF. Twenty-four rabbits were infected with 2 × 10
4
hemagglutination units of RHDV. Twelve received five doses of CT-1 (100 μg/kg) starting at 12 h postinfection (hpi) (the first three doses every 6 h and then two additional doses at 48 and 72 hpi), while the rest received saline. The animals were analyzed for survival, serum biochemistry, and viral load. Another cohort (
n
= 22) was infected and treated similarly, but animals were sacrificed at 30 and 36 hpi to analyze liver histology, viral load, and the expression of factors implicated in liver damage and repair. All infected rabbits that received saline died by 60 hpi, while 67% of the CT-1-treated animals survived until the end of the study. Treated animals showed improved liver function and histology, while the viral loads were similar. In the livers of CT-1-treated rabbits we observed reduction of oxidative stress, diminished PARP1/2 and JNK activation, and decreased inflammatory reaction, as reflected by reduced expression of tumor necrosis factor alpha,
interleukin-1β
, Toll-like receptor 4, VCAM-1, and MMP-9. In addition, CT-1-treated rabbits exhibited marked upregulation of TIMP-1 and increased expression of cytoprotective and proregenerative growth factors, including platelet-derived growth factor B, epidermal growth factor, platelet-derived growth factor receptor β, and c-Met. In conclusion, in a lethal form of acute viral hepatitis, CT-1 increases animal survival by attenuating inflammation and activating cytoprotective mechanisms, thus representing a promising therapy for ALF of viral origin.
Infection with Seasonal Influenza Virus Elicits CD4 T Cells Specific for Genetically Conserved Epitopes That Can Be Rapidly Mobilized for Protective Immunity to Pandemic H1N1 Influenza Virus
Authors: Alam Shabnam , Sant Andrea J.
Published: October 2011

In recent years, influenza viruses with pandemic potential have been a major concern worldwide. One unresolved issue is how infection or vaccination with seasonal influenza virus strains influences the ability to mount a protective immune response to novel pandemic strains. In this study, we developed a mouse model of primary and secondary influenza infection by using a widely circulating seasonal H1N1 virus and the pandemic strain of H1N1 that emerged in Mexico in 2009, and we evaluated several key issues. First, using overlapping peptide libraries encompassing the entire translated sequences of 5 major influenza virus proteins, we assessed the specificity of CD4 T cell reactivity toward epitopes conserved among H1N1 viruses or unique to the seasonal or pandemic strain by enzyme-linked immunospot (ELISpot) assays. Our data show that CD4 T cells reactive to both virus-specific and genetically conserved epitopes are elicited, allowing separate tracking of these responses. Populations of cross-reactive CD4 T cells generated from seasonal influenza infection were found to expand earlier after secondary infection with the pandemic H1N1 virus than CD4 T cell populations specific for new epitopes. Coincident with this rapid CD4 T cell response was a potentiated neutralizing-antibody response to the pandemic strain and protection from the pathological effects of infection with the pandemic virus. This protection was not dependent on CD8 T cells. Together, our results indicate that exposure to seasonal vaccines and infection elicits CD4 T cells that promote the ability of the mammalian host to mount a protective immune response to pandemic strains of influenza virus.
New insights into ion regulation of cephalopod molluscs: a role of epidermal ionocytes in acid-base regulation during embryogenesis
Authors: Hu Marian Y. , Tseng Yung-Che , Lin Li-Yih , Chen Po-Yen , Charmantier-Daures Mireille , Hwang Pung-Pung , Melzner Frank
Published: October 2011

The constraints of an active life in a pelagic habitat led to numerous convergent morphological and physiological adaptations that enable cephalopod molluscs and teleost fishes to compete for similar resources. Here, we show for the first time that such convergent developments are also found in the ontogenetic progression of ion regulatory tissues; as in teleost fish, epidermal ionocytes scattered on skin and yolk sac of cephalopod embryos appear to be responsible for ionic and acid-base regulation before gill epithelia become functional. Ion and acid-base regulation is crucial in cephalopod embryos, as they are surrounded by a hypercapnic egg fluid with a Pco2between 0.2 and 0.4 kPa. Epidermal ionocytes were characterized via immunohistochemistry, in situ hybridization, and vital dye-staining techniques. We found one group of cells that is recognized by concavalin A and MitoTracker, which also expresses Na+/H+exchangers (NHE3) and Na+-K+-ATPase. Similar to findings obtained in teleosts, these NHE3-rich cells take up sodium in exchange for protons, illustrating the energetic superiority of NHE-based proton excretion in marine systems. In vivo electrophysiological techniques demonstrated that acid equivalents are secreted by the yolk and skin integument. Intriguingly, epidermal ionocytes of cephalopod embryos are ciliated as demonstrated by scanning electron microscopy, suggesting a dual function of epithelial cells in water convection and ion regulation. These findings add significant knowledge to our mechanistic understanding of hypercapnia tolerance in marine organisms, as it demonstrates that marine taxa, which were identified as powerful acid-base regulators during hypercapnic challenges, already exhibit strong acid-base regulatory abilities during embryogenesis.
Increase of sodium delivery stimulates the mitochondrial respiratory chain H2O2production in rat renal medullary thick ascending limb
Authors: Ohsaki Yusuke , O'Connor Paul , Mori Takefumi , Ryan Robert P. , Dickinson Bryan C. , Chang Christopher J. , Lu Yi , Ito Sadayoshi , Cowley Allen W.
Published: October 2011

The mitochondria-rich epithelial cells of the renal medullary thick ascending limb (mTAL) reabsorb nearly 25% of filtered sodium (Na+) and are a major source of cellular reactive oxygen species. Although we have shown that delivery of Na+to the mTAL of rats increases superoxide (O2·−) production in mTAL, little is known about H2O2production, given the lack of robust and selective fluorescent indicators for determining changes within the whole cell, specifically in the mitochondria. The present study determined the effect of increased tubular flow and Na+delivery to mTAL on the production of mitochondrial H2O2in mTAL. H2O2responses were determined in isolated, perfused mTAL of Sprague-Dawley rats using a novel mitochondrial selective fluorescent H2O2indicator, mitochondria peroxy yellow 1, and a novel, highly sensitive and stable cytosolic-localized H2O2indicator, peroxyfluor-6 acetoxymethyl ester. The results showed that mitochondrial H2O2and cellular fluorescent signals increased progressively over a period of 30 min following increased tubular perfusion (5–20 nl/min), reaching levels of statistical significance at ∼10–12 min. Responses were inhibited with rotenone or antimycin A (inhibitors of the electron-transport chain), polyethylene glycol-catalase and by reducing Na+transport with furosemide or ouabain. Inhibition of membrane NADPH-oxidase with apocynin had no effect on mitochondrial H2O2production. Cytoplasmic H2O2(peroxyfluor-6 acetoxymethyl ester) increased in parallel with mitochondrial H2O2(mitochondria peroxy yellow 1) and was partially attenuated (∼65%) by rotenone and completely inhibited by apocynin. The present data provide clear evidence that H2O2is produced in the mitochondria in response to increased flow and delivery of Na+to the mTAL, and that whole cell H2O2levels are triggered by the mitochondrial reactive oxygen species production. The mitochondrial production of H2O2may represent an important target for development of more effective antioxidant therapies.
(In)activity-dependent alterations in resting and reflex control of splanchnic sympathetic nerve activity
Authors: Mischel Nicholas A. , Mueller Patrick J.
Published: October 2011

The negative effects of sympathetic overactivity on long-term cardiovascular health are becoming increasingly clear. Moreover, recent work done in animal models of cardiovascular disease suggests that sympathetic tone to the splanchnic vasculature may play an important role in the development and maintenance of these disease states. Work from our laboratory and others led us to hypothesize that a lack of chronic physical activity increases resting and reflex-mediated splanchnic sympathetic nerve activity, possibly through changes occurring in a key brain stem center involved in sympathetic regulation, the rostral ventrolateral medulla (RVLM). To address this hypothesis, we recorded mean arterial pressure (MAP) and splanchnic sympathetic nerve activity (SSNA) in a group of active and sedentary animals that had been housed for 10–13 wk with or without running wheels, respectively. In experiments performed under Inactin anesthesia, we tested responses to RVLM microinjections of glutamate, responses to baroreceptor unloading, and vascular reactivity, the latter of which was performed under conditions of autonomic blockade. Sedentary animals exhibited enhanced resting SSNA and MAP, augmented increases in SSNA to RVLM activation and baroreceptor unloading, and enhanced vascular reactivity to α1-receptor mediated vasoconstriction. Our results suggest that a sedentary lifestyle increases the risk of cardiovascular disease by augmenting resting and reflex-mediated sympathetic output to the splanchnic circulation and also by increasing vascular sensitivity to adrenergic stimulation. We speculate that regular physical exercise offsets or reverses the progression of these disease processes via similar or disparate mechanisms and warrant further examination into physical (in)activity-induced sympathetic nervous system plasticity.
Contribution of execution noise to arm movement variability in three-dimensional space
Authors: Apker Gregory A. , Buneo Christopher A.
Published: October 2011

Reaching movements are subject to noise associated with planning and execution, but precisely how these noise sources interact to determine patterns of endpoint variability in three-dimensional space is not well understood. For frontal plane movements, variability is largest along the depth axis (the axis along which visual planning noise is greatest), with execution noise contributing to this variability along the movement direction. Here we tested whether these noise sources interact in a similar way for movements directed in depth. Subjects performed sequences of two movements from a single starting position to targets that were either both contained within a frontal plane (“frontal sequences”) or where the first was within the frontal plane and the second was directed in depth (“depth sequences”). For both sequence types, movements were performed with or without visual feedback of the hand. When visual feedback was available, endpoint distributions for frontal and depth sequences were generally anisotropic, with the principal axes of variability being strongly aligned with the depth axis. Without visual feedback, endpoint distributions for frontal sequences were relatively isotropic and movement direction dependent, while those for depth sequences were similar to those with visual feedback. Overall, the results suggest that in the presence of visual feedback, endpoint variability is dominated by uncertainty associated with planning and updating visually guided movements. In addition, the results suggest that without visual feedback, increased uncertainty in hand position estimation effectively unmasks the effect of execution-related noise, resulting in patterns of endpoint variability that are highly movement direction dependent.
Prestin in HEK cells is an obligate tetramer
Authors: Hallworth Richard , Nichols Michael G.
Published: October 2011

The unusual membrane motor protein prestin is essential for mammalian hearing and for the survival of cochlear outer hair cells. While prestin has been demonstrated to be a homooligomer, by Western blot and FRET analyses, the stoichiometry of self association is unclear. Prestin, coupled to the enhanced green fluorescent protein, was synthesized and membrane targeted in human embryonic kidney cells by plasmid transfection. Fragments of membrane containing immobilized fluorescent molecules were isolated by osmotic lysis. Diffraction-limited fluorescent spots consistent in size with single molecules were observed. Under continuous excitation, the spots bleached to background in sequential and approximately equal-amplitude steps. The average step count to background levels was 2.7. A binomial model of prestin oligomerization indicated that prestin was most likely a tetramer, and that a fraction of the green fluorescent protein molecules was dark. As a positive control, the same procedure was applied to cells transfected with plasmids coding for the human cyclic nucleotide-gated ion channel A3 subunit (again coupled to the enhanced green fluorescent protein), which is an obligate tetramer. The average step count for this molecule was also 2.7. This result implies that in cell membranes prestin oligomerizes to a tetramer.