bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and Experiments of a Haptic Telemanipulation Environment for a Microrobot Driven by Centripetal Forces
Authors: Vlachos Kostas , Papadopoulos Evangelos
Published: November 2008

This paper presents the analytical and experimental results on a new haptic telemanipulation environment for microrobot control. The proposed environment is comprised of a 5DOF force feedback mechanism, acting as the master, and a 2DOF microrobot, acting as the slave. The fact that the slave microrobot is driven by two centripetal force vibration micromotors makes the presented telemanipulation environment exceptional and challenging. The unique characteristics and challenges that arise during the haptic micromanipulation of the specific device are described and analyzed. The developed solutions are presented and discussed. Several experiments show that, regardless of the disparity between the master and slave, the proposed environment facilitates functional and simple microrobot control during micromanipulation operations.
Analogy of Strain Energy Density Based Bone-Remodeling Algorithm and Structural Topology Optimization
Authors: Jang In Gwun , Kim Il Yong , Kwak Byung Man
Published: November 2008

In bone-remodeling studies, it is believed that the morphology of bone is affected by its internal mechanical loads. From the 1970s, high computing power enabled quantitative studies in the simulation of bone remodeling or bone adaptation. Among them, Huiskes et al. (1987, “Adaptive Bone Remodeling Theory Applied to Prosthetic Design Analysis,” J. Biomech. Eng., 20, pp. 1135–1150) proposed a strain energy density based approach to bone remodeling and used the apparent density for the characterization of internal bone morphology. The fundamental idea was that bone density would increase when strain (or strain energy density) is higher than a certain value and bone resorption would occur when the strain (or strain energy density) quantities are lower than the threshold. Several advanced algorithms were developed based on these studies in an attempt to more accurately simulate physiological bone-remodeling processes. As another approach, topology optimization originally devised in structural optimization has been also used in the computational simulation of the bone-remodeling process. The topology optimization method systematically and iteratively distributes material in a design domain, determining an optimal structure that minimizes an objective function. In this paper, we compared two seemingly different approaches in different fields—the strain energy density based bone-remodeling algorithm (biomechanical approach) and the compliance based structural topology optimization method (mechanical approach)—in terms of mathematical formulations, numerical difficulties, and behavior of their numerical solutions. Two numerical case studies were conducted to demonstrate their similarity and difference, and then the solution convergences were discussed quantitatively.
Adaptive Surrogate Modeling for Efficient Coupling of Musculoskeletal Control and Tissue Deformation Models
Authors: Halloran Jason P. , Erdemir Ahmet , van den Bogert Antonie J.
Published: November 2008

Finite element (FE) modeling and multibody dynamics have traditionally been applied separately to the domains of tissue mechanics and musculoskeletal movements, respectively. Simultaneous simulation of both domains is needed when interactions between tissue and movement are of interest, but this has remained largely impractical due to the high computational cost. Here we present a method for the concurrent simulation of tissue and movement, in which state of the art methods are used in each domain, and communication occurs via a surrogate modeling system based on locally weighted regression. The surrogate model only performs FE simulations when regression from previous results is not within a user-specified tolerance. For proof of concept and to illustrate feasibility, the methods were demonstrated on an optimization of jumping movement using a planar musculoskeletal model coupled to a FE model of the foot. To test the relative accuracy of the surrogate model outputs against those of the FE model, a single forward dynamics simulation was performed with FE calls at every integration step and compared with a corresponding simulation with the surrogate model included. Neural excitations obtained from the jump height optimization were used for this purpose and root mean square (RMS) difference between surrogate and FE model outputs (ankle force and moment, peak contact pressure and peak von Mises stress) were calculated. Optimization of the jump height required 1800 iterations of the movement simulation, each requiring thousands of time steps. The surrogate modeling system only used the FE model in 5% of time steps, i.e., a 95% reduction in computation time. Errors introduced by the surrogate model were less than 1mm in jump height and RMS errors of less than 2N in ground reaction force, 0.25Nm in ankle moment, and 10kPa in peak tissue stress. Adaptive surrogate modeling based on local regression allows efficient concurrent simulations of tissue mechanics and musculoskeletal movement.
Integrating a Grasp Exoskeleton Into a String-Based Interface for Human-Scale Interactions
Authors: Fesharakifard Rasul , Khalili Maryam , Leroy Laure , Paljic Alexis , Fuchs Philippe
Published: November 2008

A grasp exoskeleton actuated by a string-based platform is proposed to provide the force feedback for a user’s hand in human-scale virtual environments. The user of this interface accedes to seven active degrees of freedom in interaction with virtual objects, which comprises three degrees of translation, three degrees of rotation, and one degree of grasping. The exoskeleton has a light and ergonomic structure and provides the grasp gesture for five fingers. The actuation of the exoskeleton is performed by eight strings that are the parallel arms of the platform. Each string is connected to a block of motor, rotary encoder, and force sensor with a novel design to create the necessary force and precision for the interface. A hybrid control method based on the string’s tension measured by the force sensor is developed to resolve the ordinary problems of string-based interface. The blocks could be moved on a cubic frame around the virtual environment. Finally the results of preliminary experimentation of interface are presented to show its practical characteristics. Also the interface is mounted on an automotive model to demonstrate its industrial adaptability.
Reading culture from tobacco advertisements in Indonesia
Authors: Nichter Mimi , Padmawati S , Danardono M , Ng N , Prabandari Y , Nichter Mark
Published: November 2008

Background:

Tobacco advertising in Indonesia is among the most aggressive and innovative in the world, and tobacco advertisements saturate the environment. Tobacco companies are politically and financially powerful in the country because they are one of the largest sources of government revenue. As a result, there are few restrictions on tobacco marketing and advertising. National surveys reveal that 62% of men and 1% to 3% of women are smokers. Over 90% of smokers smoke clove cigarettes (kretek). This paper examines the social and cultural reasons for smoking in Indonesia and discusses how the tobacco industry reads, reproduces and works with culture as a means of selling cigarettes. An analysis is provided of howkretektobacco companies represent themselves as supporters of Indonesian national identity. This analysis is used to identify strategies to break the chains of positive association that currently support widespread smoking.

Methods:

Between November 2001 and March 2007, tobacco advertisements were collected from a variety of sources, including newspapers and magazines. Frequent photographic documentation was made of adverts on billboards and in magazines. Advertisements were segmented into thematic units to facilitate analysis. In all, 30 interviews were conducted with smokers to explore benefits and risks of smoking, perceptions of advertisements and brand preferences. Focus groups (n = 12) were conducted to explore and pretest counter advertisements.

Results:

Key themes were identified in tobacco advertisements including control of emotions, smoking to enhance masculinity and smoking as a means to uphold traditional values while simultaneously emphasising modernity and globalisation. Somekretekadvertisements are comprised of indirect commentaries inviting the viewer to reflect on the political situation and one’s position in society.

Conclusions:

After identifying key cultural themes in cigarette advertisements, our research group is attempting to engage the tobacco industry on “cultural ground” to reduce consumption and social acceptability. To do this, we need to take back social spaces that the tobacco industry has laid claim to through advertising. Active monitoring and surveillance of tobacco advertising strategies is necessary and legislation and enforcement to curb the industry should be put in place.
Analysis of Double-Tagging Experiments: An Update
Authors: Russell Jr. Howard J.
Published: November 2008

A mathematically corrected version of a previously published method for analyzing results of double-tagging experiments is presented. Analytical procedures are exemplified using lobster tag return data.Key words: Double-tagging, analysis, update
Concentrations of Leucine Aminonaphthylamidase (LAN) and Soluble Protein in Tissues of Rainbow Trout, Salmo gairdneri
Authors: Bouck Gerald R.
Published: November 2008

The levels of soluble protein (Biuret-reactive) and levels of leucine aminonaphthylamidase (LAN, 3.4.1.1) were determined quantitatively in extracts of 10 organs from rainbow trout (Salmo gairdneri). Soluble protein had a very discrete distribution and averaged 5.2 times more concentrated in liver than in blood plasma (3.5 g/100 mL). LAN was present in the extract of every tissue except saline-washed brain. LAN activity was highest in hindgut, 36 more times more concentrated than in the plasma of healthy fish. Wasting disorders such as caused by stress, would likely increase the level of necrosis which in turn would increase the amount of LAN in plasma. I propose that a "tissue equivalent" unit of LAN to provide a means of relating increased LAN in plasma to an amount of liver destruction in vitro that would render a similar amount of LAN.Key words: plasma enzymes, stress, plasma protein, rainbow trout, leucine aminonaphthylamidase, fish physiology
Swimming Performance and Behavior of Rainbow Trout (Salmo gairdneri) and White Perch (Morone americana): Effects of Attaching Telemetry Transmitters
Authors: Mellas Ernest J. , Haynes James M.
Published: November 2008

Implicit in biotelemetry studies is the assumption that transmitter attachment does not affect fish behavior or performance. We conducted experiments to determine effects of external, surgical, and stomach tag attachments on the swimming performance and behavior of rainbow trout (Salmo gairdneri) and white perch (Morone americana). Only one rainbow trout changed dominance rank after dummy tag attachment. Subordinate fish had significantly lower weights than subdominant and dominant fish, but there were no significant differences in exhaustion times. Externally tagged trout had significantly lower exhaustion times than other tagged groups and controls. There was no significant difference in exhaustion times among tagged white perch and controls. Externally and surgically tagged perch contracted serious fungal infections during a 45-d survival study; however, few disease and no survival problems among tagged and untagged rainbow trout were noted up to 21 d. With all factors taken into account, it appears that stomach tagging is the best method of transmitter attachment, except when regurgitation and/or stomach atrophy are likely to be encountered.
Physiological Smolt Characteristics of Anadromous and Non-anadromous Brook Trout (Salvelinus fontinalis) and Atlantic Salmon (Salmo salar)
Authors: McCormick Stephen D. , Naiman Robert J. , Montgomery Ellyn T.
Published: November 2008

Anadromous brook trout, Salvelinus fontinalis, of rivière à la Truite, Quebec, were examined for physiological changes associated with smoltification, and compared with non-anadromous brook trout from the adjacent Matamek River. There were no statistical differences in plasma thyroxine concentration, gill Na+, K+-ATPase activity, hematocrit, or osmoregulatory ability between the populations. Moisture content was different between the populations, but both had the same pattern of declining moisture content as summer progressed. Silver coloration of brook trout in rivière à la Truite was associated with larger fish and higher gill Na+, K+-ATPase activity, but not with changes in plasma thyroxine concentrations, moisture content, hematocrit, or condition factor. Brook trout at high-salinity estuarine sites had greater gill Na+, K+-ATPase activity and hypoosmoregulatory ability than those from low-salinity sites. Silvering of Atlantic salmon (Salmo salar) in rivière à la Truite was associated with larger fish, higher gill Na+, K+-ATPase activity, and higher plasma thyroxine. Gill Na+, K+-ATPase activity of highly silvered freshwater Atlantic salmon was greater than that of highly silvered brook trout. Estuarine Atlantic salmon had significantly higher plasma thyroxine concentration and gill Na+, K+-ATPase activity than estuarine brook trout. Based on these physiological factors, we conclude that smoltification is undeveloped in brook trout and that estuarine residence is important for salt water acclimation and eventual seaward migration.
Factors Regulating in situ Filtering Rates of Cladocera
Authors: Chow-Fraser Patricia , Knoechel Roy
Published: November 2008

Individual filtering rates of four species of Daphnia, as well as Holopedium, Diaphanosoma, Ceriodaphnia, and Bosmina, were measured in 10 lakes under various field conditions to identify important factors regulating in situ filter-feeding for these cladocerans. Linear regression analysis indicated that carapace length accounted for almost 60% of the total variance in individual filtering rates when data from all 10 lakes were pooled. We suggest that zooplankton in these lakes filter-feed in proportion to their volume, since the functional slope of this regression approximated 3. Taxonomic affiliation had generally little effect on filtering rates. Temperature, ranging from 12 to 22 °C, had no statistically significant effect on filtering rate; there were also no significant differences between rates measured at dawn and dusk compared with midday rates for animals ranging in size between 0.30 and 1.30 mm. Addition of phytoplankton concentration as a second independent variable to the regression relating filtering rate to length further increased explained variance to 64%. Since the two main determinants of in situ filtering rates were zooplankton carapace length and concentration of edible phytoplankton, both of which are independent of taxonomic affiliation, investigators interested in assessing grazing losses should seriously consider measuring zooplankton in terms of size distribution rather than taxonomic affiliation.
Early Life History of Atlantic Mackerel (Scomber scombrus) in the Southern Gulf of St. Lawrence
Authors: Ware D. M. , Lambert T. C.
Published: November 2008

Results of a 4-yr study of the vertical distribution, development, and mortality of the early life history stages of Atlantic mackerel (Scomber scombrus) in St. Georges Bay, Nova Scotia, are summarized. Adult mackerel migrate to the southern Gulf of St. Lawrence and first appear in St. Georges Bay in the spring when the sea surface temperature is 7–8 °C. Peak spawning occurs about 26 d later, when the water temperature has warmed to 13 °C. Mackerel eggs tend to concentrate near the surface, particularly under light winds, and decline exponentially with depth. The rate of decline was a function of egg diameter and the temperature gradient in the top 5 m. During incubation, which lasts about 6 d, the median depth of the eggs increased at a rate of 1 m/d. This explains why recently hatched larvae were primarily between 5 and 10 m. As the larvae grew they moved progressively closer to the surface during the day; between the 3- to 8-mm stage the median depth decreased at a rate of 0.7 m/d. Mortality in the egg stage was of the order of 41%/d, and increased with respect to the annual rate of warming of the mixed layer. Larval mortality rates (corrected for net avoidance) were about 42%/d and were positively correlated with temperature. Although the mortality rate tended to be higher amongst first-feeding larvae, events during this stage did not change the rank order of abundance of the year classes — mortality was consistently high from fertilization to the 8-mm stage. There is some evidence in 1975, which was the warmest year, and the year with the highest larval mortality rate, that there was a poor spatial match between the size of mackerel larvae, at different depths, and the size of their planktonic food supply.
A Method for Measuring Horizontal Transport of Organic Carbon Over Sediments
Authors: Grant Jonathan
Published: November 2008

Prewashed, precombusted sand from a sheltered beach in Nova Scotia was returned to the beach at low tide in metal pans. Hourly sampling of pans during high tide was used to assess gross deposition of organic carbon to the bed, with sampling at successive low tides to derive net deposition rate. Resuspension was considered to be the difference between gross and net deposition. Short-term burial of carbon was measured by vertically sectioning pan samples. The results indicate that due to resuspension, the rate of net deposition over 2 d (11 gC∙m−1∙h−1) was only 42% of the rate of gross deposition that occurred during a single high tide. The method is useful because it can resolve the short-term particle fluxes that may be trophically important to benthic communities.
El Niño Events and Variability in a Pacific Mackerel (Scomber japonicus) Survival Index: Support for Hjort's Second Hypothesis
Authors: Sinclair M. , Tremblay M. J. , Bernal P.
Published: November 2008

From 1928 to 1965 the higher survival rates to age 1 for Pacific mackerel (Scomber japonicus) in the California Current occurred during years of decreased southward transport (as indicated by sea level), which in turn is related to El Niño events. During such years, plankton biomass was relatively low. Conversely, Pacific mackerel survival rates to age 1 were low during periods of increased southward transport, when plankton biomass was high. We conclude that survival rates during the early life history may be more influenced by hydrographic processes in a direct manner than by biological interactions. This interpretation is consistent with Hjort's (1914. Rapp. P.-V. Réun. Cons. Int. Explor. Mer 20: 1–228) second hypothesis to explain interannual variability in recruitment to fish populations.
Influence of Water Hardness, pH, and Alkalinity on the Mechanisms of Copper Toxicity in Juvenile Rainbow Trout,Salmo gairdneri
Authors: Laurén Darrel Jon , McDonald D. G.
Published: November 2008

Juvenile rainbow trout were exposed to 25–400 μg copper∙L−1for 24 h. Water hardness, pH, and alkalinity were varied independently at a constant [Na+]. Net and unidirectional sodium fluxes were measured in hard and soft, low-alkalinity water and in hard, high-alkalinity water at neutral pH and pH 5.0. In low alkalinity water, Na+uptake (Jin) was inhibited at copper concentrations as low as 25 μg∙L−1, and sodium efflux (Jout) was stimulated above 100 μg∙L−1. High-alkalinity water significantly reduced the effects of copper on Jinand Jout, but there was no significant effect of increasing water hardness. The effects of pH 5.0 and copper were additive from 25 to 100 μg∙L−1, but a pure copper effect was found from 200 to 400 μg∙L−1. Fish died when they had lost about 50–55% of their exchangeable Na+pool. Water hardness and alkalinity had no effect on the apparent uptake of copper, but copper uptake was reduced by about 50% at pH 5.0.
Effects of Clear-cut Logging with and without Buffer Strips on juvenile Salmonids in Alaskan Streams
Authors: Murphy Michael L. , Heifetz Jonathan , Johnson Scott W. , Koski K V. , Thedinga John F.
Published: November 2008

To assess short-term effects of logging on juvenile Oncorhynchus kisutch, Salvelinus malma, Salmo gairdneri, and Salmo clarki in southeastern Alaska, we compared fish density and habitat in summer and winter in 18 streams in old-growth forest and in clearcuts with and without buffer strips. Buffered reaches did not consistently differ from old-growth reaches; clear-cut reaches had more periphyton, lower channel stability, and less canopy, pool volume, large woody debris, and undercut banks than old-growth reaches. In summer, if areas had underlying limestone, clear-cut reaches and buffered reaches with open canopy had more periphyton, benthos, and coho salmon fry (age 0) than old-growth reaches. In winter, abundance of parr (age > 0) depended on amount of debris. If debris was left in clear-cut reaches, or added in buffered reaches, coho salmon parr were abundant (10–22/100 m2). If debris had been removed from clear-cut reaches, parr were scarce (< 2/100 m2). Thus, clear-cutting may increase fry abundance in summer in some streams by increasing primary production, but may reduce abundance of parr in winter if debris is removed. Use of buffer strips maintains or increases debris, protects habitat, allows increased primary production, and can increase abundance of fry and parr.
Food Resource Utilization by Five Species of Benthic Feeding Fish in Passamaquoddy Bay, New Brunswick
Authors: Macdonald J. Stevenson , Green Roger H.
Published: November 2008

Feeding relationships of various fish species, and their relationship to the composition of the surrounding sediments, were observed for 1 yr at two sites in the lower Bay of Fundy region. The fishes were the ocean pout (Macrozoarces americanus, Zoarcidae), winter flounder (Pseudopleuronectes americanus, Pleuronectidae), plaice (Hippoglossoides platessoides, Pleuronectidae), cod (Gadus morhua, Gadidae), and witch flounder (Glyptocephalus cynoglossus, Pleuronectidae). After reducing the size of the data matrix by removing redundant variables, we used discriminant function analysis to assess interspecific diet overlap and the degree to which stomach contents reflect benthic composition. Variables were ranked by their power to discriminate in pairwise comparisons among fish species and between a given fish species and benthic grab samples. Many amphipods are utilized to an equal or greater extent than their abundances in the sediments would suggest. Many annelids are underutilized. Predation by each fish species was a selective process, and interspecific diet differences are related to the morphology of the predator and the behavior and microhabitat of the prey. The fishes diets, however, are also correlated with spatial and temporal changes in the benthic composition. Specific examples are presented. As benthic food abundance increased in the surrounding sediments all predator species increased their food consumption and interspecific diet overlap declined. In some cases the degree of exploitation depended upon the size rather than the abundance of the prey item.
New Method for Ageing Chinook Salmon (Onchorhynchus tshawytscha) Using Dorsal Fin Rays, and Evidence if Its Validity
Authors: Chilton D. E. , Bilton H. T.
Published: November 2008

Age of spawning chinook salmon (Oncorhynchus tshawytscha) was estimated using a combination of thin cross-sections from the dorsal fin rays and scales. The latter were used when freshwater growth could not be interpreted from fin rays. Fish of known age were used when available. Results were compared with ages obtained from scales only. Due to scale resorption a significant proportion of the older fish ages was undetected using only scales. Determinations of freshwater age from fin rays and from scales were in agreement 88.5 ± 8.7 to 92.3 ± 7.2% at the 95% confidence level. Thus, the fin ray method provided virtually the same freshwater age as did the scale method. Also, fin rays provided quite acceptable estimation of ocean age. It is recommended that managers use a combination of scales and fin rays to estimate the total age of spawning chinook salmon.
ABOUT THE ENERGY OF AdS–KERR SOLUTIONS
Authors: FATIBENE L. , FERRARIS M. , FRANCAVIGLIA M.
Published: November 2008

In the framework of augmented variational principles we recover here the conserved quantities proposed by Gibbons et al. for Kerr–AdS solutions.
Protective role of angiotensin II type 2 receptor signaling in a mouse model of pancreatic fibrosis
Authors: Ulmasov Barbara , Xu Zekuan , Tetri Laura H. , Inagami Tadashi , Neuschwander-Tetri Brent A.
Published: November 2008

The renin-angiotensin system contributes to pathological processes in a variety of organs. In the pancreas, blocking the angiotensin II (AII) type 1 receptor (AT1) attenuates pancreatic fibrogenesis in animal models of pancreatitis. Because the role of the AII type 2 receptor (AT2) in modulating pancreatic injury is unknown we investigated the role of AT2 in pancreatic injury and fibrosis. Pancreatic fibrosis was induced by repetitive cerulein administration in C57BL/6 wild-type (WT) or AT2-deficient (AT2−/−) mice and assessed by morphology and gene expression at 10 days. There was no difference between WT and AT2−/− mice in the degree of acute pancreatic injury as assessed by amylase release at 9 and 12 h and by histological examination of the pancreas at 12 h. In contrast, parenchymal atrophy and fibrosis were more pronounced in AT2−/− mice compared with WT mice at 10 days. Fibrosis was accompanied by activation of pancreatic stellate cells (PSC) evaluated by Western blot analysis for α-smooth muscle actin and by immunocytochemistry; PSC activation was further increased in AT2−/− mice compared with WT mice. The level of pancreatic transforming growth factor-β1 mRNA and protein after repetitive cerulein treatment was higher in AT2−/− mice than in WT mice. Our results demonstrate that, in contrast to AT1 receptor signaling, AT2 receptor signaling modulates protective antifibrogenic effects in a mouse model of cerulein-induced pancreatic fibrogenesis. We propose that the effects of AII on injury-induced pancreatic fibrosis may be determined by the balance between AT1 and AT2 receptor signaling.
Apical targeting and Golgi retention signals reside within a 9-amino acid sequence in the copper-ATPase, ATP7B
Authors: Braiterman Lelita , Nyasae Lydia , Guo Yan , Bustos Rodrigo , Lutsenko Svetlana , Hubbard Ann
Published: November 2008

ATP7B is a copper-transporting P-type ATPase present predominantly in liver. In basal copper, hepatic ATP7B is in a post-trans-Golgi network (TGN) compartment where it loads cytoplasmic Cu(I) onto newly synthesized ceruloplasmin. When copper levels rise, the protein redistributes via unique vesicles to the apical periphery where it exports intracellular Cu(I) into bile. We want to understand the mechanisms regulating the copper-sensitive trafficking of ATP7B. Earlier, our laboratory reported the presence of apical targeting/TGN retention information within residues 1–63 of human ATP7B; deletion of these residues resulted in a mutant protein that was not efficiently retained in the post-TGN in low copper and constitutively trafficked to the basolateral membrane of polarized, hepatic WIF-B cells with and without copper ( 13 ). In this study, we used mutagenesis and adenovirus infection of WIF-B cells followed by confocal immunofluorescence microscopy analysis to identify the precise retention/targeting sequences in the context of full-length ATP7B. We also analyzed the expression of selected mutants in livers of copper-deficient and -loaded mice. Our combined results clearly demonstrate that nine amino acids, F37AFDNVGYE45, comprise an essential apical targeting determinant for ATP7B in elevated copper and participate in the TGN retention of the protein under low-copper conditions. The signal is novel, does not require phosphorylation, and is highly conserved in ∼24 species of ATP7B. Furthermore, N41S, which is part of the signal we identified, is the first and only Wilson disease-causing missense mutation in residues 1–63 of ATP7B. Expression of N41S-ATP7B in WIF-B cells severely disabled the targeting and retention of the protein. We present a working model of how this physiologically relevant signal might work.
PKC-dependent stimulation of the human MCT1 promoter involves transcription factor AP2
Authors: Saksena Seema , Dwivedi Alka , Gill Ravinder K. , Singla Amika , Alrefai Waddah A. , Malakooti Jaleh , Ramaswamy Krishnamurthy , Dudeja Pradeep K.
Published: November 2008

Monocarboxylate transporter (MCT1) plays an important role in the absorption of short-chain fatty acids (SCFA) such as butyrate in the human colon. Previous studies from our laboratory have demonstrated that phorbol ester, PMA (1 μM, 24 h), upregulates butyrate transport and MCT1 protein expression in human intestinal Caco-2 cells. However, the molecular mechanisms involved in the transcriptional regulation of MCT1 gene expression by PMA in the intestine are not known. In the present study, we showed that PMA (0.1 μM, 24 h) increased the MCT1 promoter activity (−871/+91) by approximately fourfold. A corresponding increase in MCT1 mRNA abundance in response to PMA was also observed. PMA-induced stimulation of MCT1 promoter activity was observed as early as 1 h and persisted until 24 h, suggesting that the effects of PMA are attributable to initial PKC activation. Kinase inhibitor and phosphorylation studies indicated that these effects may be mediated through activation of the atypical PKC-ζ isoform. 5′-deletion studies demonstrated that the MCT1 core promoter region (−229/+91) is the PMA-responsive region. Site-directed mutagenesis studies showed the predominant involvement of potential activator protein 2 (AP2) binding site in the activation of MCT1 promoter activity by PMA. In addition, overexpression of AP2 in Caco-2 cells significantly increased MCT1 promoter activity in a dose-dependent manner. These findings showing the regulation of MCT1 promoter by PKC and AP2 are of significant importance for an understanding of the molecular regulation of SCFA absorption in the human intestine.
Enhancement of Ammonia Sensitivity in Swift Heavy Ion Irradiated Nanocrystalline SnO2 Thin Films
Authors: Rani Sanju , Roy Somnath C. , Puri N. K. , Bhatnagar M. C. , Kanjilal D.
Published: November 2008

Swift heavy ion irradiation is an effective technique to induce changes in the microstructure and electronic energy levels of materials leading to significant modification of properties. Here we report enhancement of ammonia (NH3) sensitivity of SnO2 thin films subjected to high‐energy Ni+ ion irradiation. Sol‐gel‐derived SnO2 thin films (100 nm thickness) were exposed to 75 MeV Ni+ ion irradiation, and the gas response characteristics of irradiated films were studied as a function of ion fluence. The irradiated films showed p‐type conductivity with a much higher response to NH3 compared to other gases such as ethanol. The observed enhancement of NH3 sensitivity is discussed in context of ion beam generated electronic states in the SnO2 thin films.
Fractal Analysis of Stealthy Pathfinding Aesthetics
Authors: Coleman Ron
Published: November 2008

This paper uses a fractal model to analyze aesthetic values of a new class of obstacle‐prone or “stealthy” pathfinding which seeks to avoid detection, exposure, openness, and so forth in videogames. This study is important since in general the artificial intelligence literature has given relatively little attention to aesthetic outcomes in pathfinding. The data we report, according to the fractal model, suggests that stealthy paths are statistically significantly unique in relative aesthetic value when compared to control paths. We show furthermore that paths generated with different stealth regimes are also statistically significantly unique. These conclusions are supported by statistical analysis of model results on experimental trials involving pathfinding in randomly generated, multiroom virtual worlds.
Lung Sound Analysis in the Diagnosis of Obstructive Airway Disease
Authors: Wang Zhen , Jean Smith , Bartter Thaddeus
Published: November 2008

Background: Dyspnea is prevalent and has a broad differential diagnosis. Difficulty in determining the correct etiology can delay proper treatment. Non-invasively obtained acoustic signals may offer benefit in identifying patients with dyspnea due to obstructive airway disease (OAD). Objectives: The aim of this pilot study was to determine whether patients with acute dyspnea due to OAD had distinguishing features when studied with a computerized acoustic-based imaging technique. Methods: Respiratory sounds from patients with dyspnea due to OAD (n = 32) and those with dyspnea not due to OAD (n = 39) were studied and compared with normal controls (n = 16). Results: In patients without OAD and in controls, the ratios of peak inspiratory to peak expiratory vibration energy values (peak I/E vibration ratio) were remarkably similar, 6.3 ± 5.1 and 5.6 ± 4, respectively. For the OAD patients, the peak I/E vibration ratio was significantly lower at 1.3 ± 0.04 (p < 0.01). In the patients without OAD and the controls, the ratios of inspiratory time to expiratory time (I/E time ratio) were again similar, 1.0 ± 0.1 and 0.99 ± 0.11, respectively. For the OAD patients, the I/E time ratio was significantly lower at 0.72 ± 0.19 (p < 0.01). Conclusions: This modality was useful in identifying patients whose dyspnea was due to OAD. The ability to objectively and non-invasively measure these differences may prove clinically useful in distinguishing the operant physiology in patients presenting with acute dyspnea.
Metoprolol Succinate Combination in the Treatment of Hypertension
Authors: Papadopoulos Dimitris P. , Papademetriou Vasilios
Published: November 2008

Metoprolol is a selective β(l)-adrenergic antagonist extensively used since 1975. Metoprolol has proven its efficacy in reducing cardiovascular events and mortality in patients with hypertension and coronary heart disease. A recently developed controlled release/extended-release formulation of metoprolol succinate was designed to provide relatively constant metoprolol plasma concentrations and β(l)-blockade while retaining the convenience of once daily administration. A 100-mg metoprolol controlled/extended-release tablet contains 95 mg of metoprolol succinate and is considered to have equivalent activity of 100 mg metoprolol tartrate. After ingestion, the tablet disintegrates into individual pellets and each pellet acts as a diffusion cell releasing the drug at a relatively constant rate over a period of approximately 20 hours. The aim of this review was to determine the pharmacokinetic and pharmacodynamic properties of metoprolol succinate and to apply those properties in combination with other drugs mainly diuretics in the treatment of hypertension.
Relationships of Social Context and Identity to Problem Behavior Among High-Risk Hispanic Adolescents
Authors: Schwartz Seth J. , Mason Craig A. , Pantin Hilda , Wei Wang  , Hendricks Brown C. , Campo Ana E. , Szapocznik José
Published: November 2008

The present study was designed to examine (a) family and school functioning and (b) personal and ethnic identity are associated with conduct problems, drug use, and sexual risk taking in a sample of 227 high-risk Hispanic adolescents. Adolescents participated in the study with their primary parents, who were mostly mothers. Adolescents completed measures of family and school functioning, personal and ethnic identity, conduct problems, and drug use. Parents completed measures of family functioning and adolescent conduct problems. Results indicated that school functioning and personal identity confusion are related to alcohol use, illicit drug use, and sexual risk taking indirectly through adolescent reports of conduct problems. Adolescent reports of family functioning are related to alcohol use, illicit drug use, and sexual risk taking through school functioning and conduct problems. Results are discussed in terms of the problem behavior syndrome and in terms of the finding of relative independence of contextual and identity variables vis-à-vis conduct problems, substance use, and sexual risk taking.
Youth Sports Participation and Attitudes Toward Societal Competition, Concern for Material Items, and the Consequences of Manipulative Advertising
Authors: Denham Bryan E.
Published: November 2008

Grounded in social cognitive theory, this study examines how a combination of personal, behavioral and environmental factors among youth populations correspond with attitudes toward competition, concern for material items, and the effects of advertising practices in the United States. Of particular interest was whether school-sponsored sports participation appeared to influence respondent attitudes. Drawing on data gathered from high school seniors in the 2005 Monitoring the Future study ( N = 2,579), ordinary least squares (OLS) and ordinal logistic regression analyses revealed greater support for societal competition, material items, and persuasive advertising appeals among men, those who socialized the most with friends, and those who participated the most in school-sponsored sports. In addition to sex and socializing with friends, controls included race, exposure to print media, and participation in recreational sports.
A New Immunomodulatory Therapy for Severe Sepsis: Ulinastatin Plus Thymosin α 1
Authors: Li Yumin  , Chen Hao  , Li Xun  , Zhou Wence  , He Minyan  , Chiriva-Internati M. , Wachtel M.S. , Frezza E.E.
Published: November 2008

Objectives: To study the effect of immunomodulatory therapy with ulinastatin plus thymosin α 1 on septic patients. Method: A total of 56 sepsis patients were randomized into a treatment group, receiving immunomodulatory therapy, and a placebo group, a placebo. Acute Physiology and Chronic Health Evaluation II scores, clinical data, lymphocyte subsets, immunological indexes, and coagulation parameters were determined before admission and on the 3rd, 8th, and 28th day after admission to the Intensive Care Unit. Results: The treatment group experienced a 78% cumulative survival, the placebo group experienced a 60% cumulative survival; the survival difference was mirrored by Acute Physiology and Chronic Health Evaluation II scores and more quickly improved leukocyte counts, lymphocyte counts, coagulation parameters, and cytokine levels in the treatment. Conclusions: Combined immunomodulatory therapy with ulinastatin plus thymosin α1 appears to yield improved survival for patients with sepsis; this finding should be verified in larger clinical trials.
Acrylic Copolymers as Candidates for Drug-Eluting Coating of Vascular Stents
Authors: Silvestri D. , Cristallini C. , Gagliardi M. , Barbani N. , D'Acunto M. , Ciardelli G. , Giusti P.
Published: November 2008

The aim of the present work is the synthesis and characterization of polymer materials showing good adhesion, drug loading, and delivery properties, for potential cardiovascular application. In particular, poly(methylmethacrylate-co-acrylic acid) copolymers are prepared in different compositions by a radical polymerization and investigated as potential materials to coat metallic stents and to carry out a local drug release. Films obtained by dissolving the copolymer in an appropriate organic solvent (also loaded with an anti-restenosis drug, such as tacrolimus) are investigated: physicochemical properties, adhesiveness to metallic stent material, and kinetics of drug release in physiological environment are studied.
Preparation and Evaluation of Dental Resin Luting Agents with Increasing Content of Bisphenol-A Ethoxylated Dimethacrylate
Authors: Moraes Rafael R. , Sinhoreti Mário A.C. , Correr-Sobrinho Lourenço , Ogliari Fabrício A. , Piva Evandro , Petzhold Cesar L.
Published: November 2008

Resin luting agents in which bisphenol-A glycidyl dimethacrylate (Bis-GMA) and/or triethylene glycol dimethacrylate (TEGDMA) are replaced with increasing amounts of bisphenol-A ethoxylated dimethacrylate are prepared. Degree of conversion (DC), diametral tensile strength (DTS), Young’s modulus (YM), Knoop hardness (KHN), film thickness (FT), water sorption (Wsp ), and solubility are evaluated. Regression analyses investigate the substitution of each monomer. The most appreciable differences are detected when TEGDMA is replaced: decreased DC, DTS, and Wsp, and increased YM, KHN, and FT. For substitution of Bis-GMA, the only significant differences are reduced Wsp and increased YM. An ideal formulation of resin cement would make use of the three monomers.
Preparation, Characterization, and In Vitro and In Vivo Evaluation of Cellulose/Soy Protein Isolate Composite Sponges
Authors: Luo Li-Hua , Zhang Yu-Feng , Wang Xiao-Mei , Wan Yu , Chang Peter R. , Anderson Debbie P. , Chen Yun
Published: November 2008

A series of cellulose/soy protein isolate (SPI) sponges was prepared using a freeze-drying process. The effect of the SPI content on the structure of the sponges was characterized by Fourier transform infrared spectrometry (FT-IR), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). It showed that the sponges were porous in structure, and that the size of the pores increased and the thickness of the pore walls decreased as the SPI content of the sponges increased. The biocompatibility and biodegradability of the sponges were evaluated in vitro and in vivo. The cell culture experiment and SEM observations showed that L929 fibroblast cells grew and spread well on the surface and cross-section of the composite sponges. The results from MTT (3-[4,5-dimethyl-2-thiazoly1]-2,5-diphenyl-2H-tetrazolium bromide) assay indicated that the cell viability of L929 cultured in extracts from SPI-containing sponges was higher than that from the pure cellulose sponge. The historical analysis and SEM observation revealed that the SPI-containing sponges implanted from 1 to 8 months in rats exhibited better in vivo biocompatibility and biodegradability than the pure cellulose sponge. This was due to the incorporation of SPI into cellulose and to the freeze-drying process which formed large pores and thin pore walls in the composite sponges, promoting the migration of cells and tissue into the sponges, leading to gradual fusing with the implants. The new cellulose/SPI sponges thus have potential applications as biomaterials with good biocompatibility and biodegradability.
Novel Polymeric Coatings with the Potential to Control In-stent Restenosis — An In Vitro Study
Authors: Nickson C. M. , Doherty P. J. , Williams R. L.
Published: November 2008

Restenosis following percutaneous coronary intervention (PCI) is a considerable problem in long-term performance of cardiovascular stents, with a functional endothelial cell monolayer being important in its prevention. This study evaluates the influence of polymer coatings on human aortic endothelial cells (HAEC) and coronary artery smooth muscle cells (HCASMC) in vitro, in terms of morphology, cell number, and phenotype. It was demonstrated that the polymer coatings can be tailored to enhance adhesion and growth of HAECs whilst suppressing that of HCASMCs. It is concluded that one of the polymer coatings (BTL 01015) shows potential as a stent coating to enhance re-endothelialization.
The Effect of Plasminogen Activator Inhibitor-1 -675 4G/5G Polymorphism on Familial Mediterranean Fever (FMF) Disease
Authors: Ozel Demiralp Duygu , Ekim Mesiha , Akar Nejat
Published: November 2008

Familial Mediterranean fever (FMF) is an autosomal recessive disease that is the most common of a rare group of disorders collectively termed familial hereditary periodic fever syndromes, also known as autoinflammatory syndromes. FMF is predominantly affecting people of Mediterranean descent and clinically characterized by intermittent attacks of fever with peritonitis and abdominal pain, pleuritis, arthritis, or erysipelas-like rashes. Amyloidosis due to chronic inflammation progressing to renal failure is one of the most serious potential complications of this disease.

Patients with inflammatory diseases, such as systemic lupus erythematosus and rheumatoid arthritis, and conditions with chronic subclinical inflammation, like obesity and diabetes mellitus, are now considered to have an increased risk of atherosclerotic cardiovascular complications. FMF is also an inflammatory disease, and it is accepted that even during attack-free periods significant inflammatory reaction continues. However, whether this inflammatory process causes premature atherosclerosis is not known due to a lack of data.

Different studies have investigated the association between the fibrinolytic and inflammatory process parameters. PAI-1 is paracrine secretion of pro- and antiinflammatory cytokines, thereby playing a possible role in the adiposity-related inflammation and atherosclerosis. The patients with IRS have higher values of fibrinogen, factor VII, VIII, Von Willebrand factor and Plasminogen Activator Inhibitor (PAI) compared to control subjects. So that we aimed in this study to investigate whether FMF patients with/without amyloidosis and with M694V homozygote mutation, have increased risk for atherosclerotic cardiovascular complications and to determine the strength of association between MEFV gene-mutation types. To our knowledge, this is the first case control and cross-sectional study in the pediatric age groups.
New Echocardiographic Techniques for Evaluating Left Ventricular Myocardial Function
Authors: Marcucci Carlo , Lauer Ryan , Mahajan Aman
Published: November 2008

Ultrasound imaging of the heart continues to play an important role in diagnosis and management of patients with cardiovascular diseases. Recent advances in ultrasound technology and introduction of newer imaging modalities have enabled improved assessment of left ventricular myocardial function. Tissue Doppler imaging and 2-dimensional speckle tracking allow more objective quantification of myocardial function in the form of tissue velocities, displacement, strain, and strain rate. Similarly, contrast-enhanced echocardiography and 3-dimensional echocardiography have provided a unique insight into left ventricular form and function that was not possible by unenhanced 2-dimensional echocardiography. In this review, the authors discuss the clinical application of these new imaging techniques in the assessment of left ventricular myocardial function.
Real-Time 3-Dimensional Echocardiography in the Operating Room
Authors: Jungwirth Bettina , Mackensen G. Burkhard
Published: November 2008

Real-time 3-dimensional transesophageal echocardiography (RT-3D-TEE) represents a novel clinical and intuitively educational perioperative cardiovascular imaging modality. The development of RT-3D-TEE allows for live 3D imaging as it circumvents most of the disadvantages of reconstructive 3D methods. RT-3D-TEE will likely revolutionize perioperative assessment of complex 3D structures, such as the mitral valve (MV), as it provides important mechanistic insights into functional and ischemic mitral regurgitation. The MV is particularly suited to live RT-3D-TEE assessment because of the complex interrelationships among the valve, chordae, papillary muscles, and myocardial walls. The 3D en face view of the MV is in accordance with the surgical view and allows to illustrate the unique saddle shape of the MV annulus and to define and localize mitral leaflet lesions in MV prolapse, endocarditis, or congenital MV abnormalities, all potentially important in guiding surgical repair. RT-3D-TEE will soon be integrated into routine perioperative practice. Its unique ability of real-time acquisition, online rendering and cropping capabilities, accurate identification of the precise pathology and location of cardiac disease, together with its ability to promptly quantify 3D data sets using built-in software, will likely help in transitioning this modality into standard of care.