bluuebunny/crossref_metadata_2025 huggingface dataset:
Change in intramuscular inorganic phosphate during multiple sets of blood flow‐restricted low‐intensity exercise
Authors: Sugaya Masato , Yasuda Tomohiro , Suga Tadashi , Okita Koichi , Abe Takashi
Published: June 2011

Muscular blood flow reduction (BFR) during multiple sets of low‐intensity exercise training has been shown to elicit muscle hypertrophy and strength gain. Several hypotheses have been proposed to explain the hypertrophic adaptations to low‐intensity BFR exercise, which include muscle fatigue with metabolic stress. However, the change in intramuscular inorganic phosphate (Pi, an index of muscle fatigue) during multiple sets of low‐intensity exercise with BFR is poorly understood. Eight men performed four sets of unilateral plantar flexion exercise (20% 1‐RM) on a 31P‐magnetic resonance spectroscopy. Each subject wore a cuff (5‐cm wide) on the most proximal portion of the thigh; the cuff was inflated during the exercise session at three different pressures [0 mmHg as the control ± (CON), 180 mmHg as moderate restriction (BFR‐M) and 230 mmHg as high restriction (BFR‐H)]. During the first and second exercise sets, the increase in Pi was higher (P<0·05) with BFR‐H than with BFR‐M and CON. On the other hand, the decrease in Pi was lower with BFR‐H than with CON during the second and third rest periods between sets. As a result, the Pi concentration increased progressively (P<0·05) with BFR‐H, while the Pi was relatively constant with BFR‐M and CON during the exercise session. Our results suggest that intramuscular Pi accumulation during multiple sets of low‐intensity exercise can be produced only by a high level of BFR, but not by moderate reduction. The Pi accumulation was associated both with exercise and with the rest period between sets.
Anti‐tumour effects of small interfering RNA targeting anion exchanger 1 in experimental gastric cancer
Authors: Suo Wen‐Hao , Zhang Ning , Wu Ping‐Ping , Zhao Lei , Song Ling‐Jun , Shen Wei‐Wei , Zheng Lin , Tao Jing , Long Xi‐Dai , Fu Guo‐Hui
Published: June 2011

BACKGROUND AND PURPOSE Anion exchanger 1 (AE1) is an integral membrane protein found in erythrocytes. Our previous studies have demonstrated that AE1 is expressed in human gastric cancer cells and may be involved in the carcinogenesis of cancer. In this study, we further investigated the role of AE1 in gastric carcinogenesis and the anti‐tumour effects of AE1‐targeted small interfering RNAs (siRNAs) in two experimental models of gastric cancer.

EXPERIMENTAL APPROACH Molecular and cellular experiments were performed to elucidate the role of AE1 in the malignant transformation of gastric epithelium and the effects of AE1‐targeted siRNAs on gastric cancer cells. The anti‐tumour effect of the siRNA was evaluated in vivo in two mouse models, nude mice implanted with human gastric cancer xenografts (Model I) and mice with gastric cancer induced by N‐methyl‐N‐nitrosourea (MNU) and Helicobacter pylori (Model II).

KEY RESULTS AE1 was found to increase gastric carcinogenesis by promoting cell proliferation. AE1‐targeted siRNA significantly suppressed AE1 expression and hindered tumour growth. Furthermore, the siRNA markedly decreased the detection rate of gastric cancer, in parallel with an increase in atypical hyperplasia at the end of the experiment in Model II.

CONCLUSIONS AND IMPLICATIONS Knockdown of AE1 expression in gastric mucosa by administration of synthetic siRNAs significantly inhibits the growth of gastric cancer and decreases the detection rate of this tumour in experimental mice. These results suggest that AE1 is potentially a key therapeutic target and the silencing of AE1 expression in gastric mucosa could provide a new therapeutic approach for treating gastric cancer.
Complementary and Alternative Medicine Use Among Adults With Migraines/Severe Headaches
Authors: Wells Rebecca Erwin , Bertisch Suzanne M. , Buettner Catherine , Phillips Russell S. , McCarthy Ellen P.
Published: June 2011

(Headache 2011;51:1087‐1097)

Objective.— Our objective was to determine patterns, reasons for, and correlates of complementary and alternative medicine (CAM) use by US adults with migraines/severe headaches.

Background.— While many patients with chronic conditions use CAM, little is known about CAM use by adults with migraines/severe headaches.

Methods.— We compared CAM use between adults with and without self‐reported migraines/severe headaches using the 2007 National Health Interview Survey (n = 23,393), a national cross‐sectional survey.

Results.— Adults with migraines/severe headaches used CAM more frequently than those without (49.5% vs 33.9%, P < .0001); differences persisted after adjustment (adjusted odds ratio = 1.29, 95% confidence interval [1.15, 1.45]). Mind–body therapies (eg, deep breathing exercises, meditation, yoga) were used most commonly. More than 50% of adults with migraines/severe headaches reporting CAM use had not discussed it with their health care provider. Nonetheless, those with migraines/severe headaches used CAM more often than those without because of provider recommendation and because conventional treatments were perceived as ineffective or too costly. Correlates of CAM use among adults with migraines/severe headaches included anxiety, joint or low back pain, alcohol use, higher education, and living in the western USA. Only 4.5% of adults with migraines/severe headaches reported using CAM to specifically treat their migraines/severe headaches.

Conclusions.— CAM is used more often among adults with migraines/severe headaches than those without. However, few report using CAM to specifically treat migraines/severe headaches. Mind–body therapies are used most frequently. Further research is needed to understand the effectiveness and mechanisms of CAM treatments in adults with migraines/severe headaches.
Migraine and Vestibular Symptoms—Identifying Clinical Features That Predict “Vestibular Migraine”
Authors: Cohen Joshua M. , Bigal Marcelo E. , Newman Lawrence C.
Published: June 2011

Background.— Migraine and symptoms that may suggest a vestibular disorder (referred to herein broadly as vestibular symptoms—VS) often co‐exist. In part due to a lack of standardized diagnostic criteria, this relationship remains unknown to many physicians.

Objective.— To determine common clinical features that may be associated with “vestibular migraine” (VM).

Methods.— We retrospectively reviewed charts of patients diagnosed with VM at a headache center. In this group we recorded certain demographic and clinical features related to their disorder, including the most common triggers of the VS and the specific characteristics of the symptoms that suggested VM.

Results.— Our sample consisted of 147 patients (68% women, mean age = 45 years, 39% with aura). Migraine onset preceded the onset of VS by a mean of 8 years. A total of 62 patients (42%) had gradual onset of VS, while in 48 (33%) symptoms began suddenly. The most commonly reported symptoms that led to the diagnosis of VM were: unsteadiness (134; 91%), balance disturbance (120; 82%), “light‐headedness” (113; 77%), and vertigo (84; 57%). VS and headache occurred concomitantly in 48% of patients. A total of 67 (47%) patients had VS that were chronic from onset, 29 (21%) had episodic symptoms, and in 46 (32%) the VS had evolved from episodic to chronic (with an average duration of 7.04 years required for this evolution to occur).

Conclusions.— Vestibular migraine is a heterogeneous condition with varying symptomatology. As with migraine itself, symptomatic expression varies along a spectrum that extends from episodic to chronic. As the histories of many of the patients we evaluated would not meet current International Classification of Headache Disorders criteria, we suggest that new criteria which account for the heterogeneity and natural history of the disorder may be required to adequately diagnose and treat those who suffer from VM.
Effect of a Pharmacist‐Led Multicomponent Intervention Focusing on the Medication Monitoring Phase to Prevent Potential Adverse Drug Events in Nursing Homes
Authors: Lapane Kate L. , Hughes Carmel M. , Daiello Lori A. , Cameron Kathleen A. , Feinberg Janice
Published: June 2011

OBJECTIVES: To determine the extent to which the use of a clinical informatics tool that implements prospective monitoring plans reduces the incidence of potential delirium, falls, hospitalizations potentially due to adverse drug events, and mortality.

DESIGN: Randomized cluster trial.

SETTING: Twenty‐five nursing homes serviced by two long‐term care pharmacies.

PARTICIPANTS: Residents living in nursing homes during 2003 (1,711 in 12 intervention; 1,491 in 13 usual care) and 2004 (1,769 in 12 intervention; 1,552 in 13 usual care).

INTERVENTION: The pharmacy automatically generated Geriatric Risk Assessment MedGuide (GRAM) reports and automated monitoring plans for falls and delirium within 24 hours of admission or as part of the normal time frame of federally mandated drug regimen review.

MEASUREMENTS: Incidence of potential delirium, falls, hospitalizations potentially due to adverse drug events, and mortality.

RESULTS: GRAM triggered monitoring plans for 491 residents. Newly admitted residents in the intervention homes experienced a lower rate of potential delirium onset than those in usual care homes (adjusted hazard ratio (HR)=0.42, 95% confidence interval (CI)=0.35–0.52), overall hospitalization (adjusted HR=0.89, 95% CI=0.72–1.09), and mortality (adjusted HR=0.88, 95% CI=0.66–1.16). In longer stay residents, the effects of the intervention were attenuated, and all estimates included unity.

CONCLUSION: Using health information technology in long‐term care pharmacies to identify residents who might benefit from the implementation of prospective medication monitoring care plans when complex medication regimens carry potential risks for falls and delirium may reduce adverse effects associated with appropriate medication use.
Power within Parties: The Strength of the Local Party and MP Independence in Postcommunist Europe
Authors: Tavits Margit
Published: June 2011

This study argues that organizationally stronger local party branches are more powerful within the party than organizationally weaker branches: they can better perform the tasks central to the party, which include communication with, and mobilization of, voters. I further argue that this subunit power should be manifested in the parliamentary behavior and status of MPs: those from districts where the local party organization is strong are more likely (1) to behave independently in parliament and break party unity and (2) to hold leadership positions in parliamentary committees. I find support for these propositions in the analysis of 12 legislatures from four postcommunist democracies—Czech Republic, Estonia, Hungary, and Poland. The results remain robust against various alternative explanations.
Morphology and Small Subunit (SSU) rRNA Gene Sequence of the New Brackish Water Ciliate Neobakuella flava n. g., n. sp. (Ciliophora, Spirotricha, Bakuellidae) and SSU rRNA Gene Sequences of Six Additional Hypotrichs from Korea
Authors: LI LIQIONG , KHAN SADIA NAWROZ , JI DAODE , SHIN MANN KYOON , BERGER HELMUT
Published: June 2011

ABSTRACT. The morphology and the small subunit (SSU) rRNA gene sequence of the hypotrich Neobakuella flava n. g., n. sp. from the estuary of the Taehwagang River (Ulsan, South Korea) were investigated. The three frontal cirri, the composition of the midventral complex of cirral pairs and rows, and the simple dorsal kinety pattern of three bipolar kineties assign it to the urostyloid taxon Bakuellidae. The increased number of buccal and parabuccal cirri, the presence of transverse cirri, and more than one left marginal row, as well as the lack of caudal cirri separate Neobakuella n. g. from the other bakuellids. Neobakuella flava n. sp. has many 0.3 μm sized green and/or yellow usually dark‐green cortical granules and some sparsely distributed, 2 × 1 μm sized grass green with yellowish shimmer granules. The gene sequence data indicate a close relationship with Diaxonella and a distinct separation from the bakuellid Metaurostylopsis and parabirojimid Parabirojimia. The SSU rRNA gene sequences of four further urostyloids (i.e. Diaxonella pseudorubra, Anteholosticha monilata, Metaurostylopsis struederkypkeae, Pseudourostyla cristata) and two stylonychines (i.e. Sterkiella cavicola, Sterkiella histriomuscorum) from Korea were analyzed. Anteholosticha monilata, type of the genus, is clearly separated from the Holosticha clade, supporting the morphological separation from Holosticha. Sterkiella cavicola, type of Sterkiella, clusters within the stylonychines and is obviously closely related with S. histriomuscorum.
B‐site Dopant Effect on the Thermal Expansion in the (1‐x)PbTiO3‐xBiMeO3 Solid Solution (Me = Fe, In, Sc)
Authors: Hu Penghao , Chen Jun , Sun Ce , Deng Jinxia , Xing Xianran
Published: June 2011

The (1‐x)PbTiO3‐xBiMeO3 (Me = Fe, In, Sc) solid solutions were prepared and investigated using high‐temperature X‐ray diffraction for the B‐site dopant effect on their thermal expansion behaviors. Compared with PbTiO3, the negative thermal expansion of (1‐x)PbTiO3‐xBiFeO3 was enhanced, whereas that of (1‐x)PbTiO3‐xBiInO3 was a little weakened and was much weakened in (1‐x)PbTiO3‐xBiScO3. An empirical linear correlation between the average effective radius of the B‐site cations and the unit cell volumes at Curie point of the solid solutions was concluded. The relationship was also observed in other PbTiO3‐BiMeO3‐type solid solutions and was supposed to be widely useful in predicting the thermal expansion coefficient of compounds of this sort. Above the Curie point, the unit cell volumes of the compounds were determined by the radii of the doped B‐site cations. The weaking and vanishing of the lattice distortion caused by spontaneous polarization displacements was proved by Raman scatting spectrum, which supported the relationship in the lattice dynamic aspect.
Plasma membrane microdomains regulate TACE‐dependent TNFR1 shedding in human endothelial cells
Authors: D.’Alessio Alessio , Esposito Bianca , Giampietri Claudia , Ziparo Elio , Pober Jordan S. , Filippini Antonio
Published: June 2011

Upon stimulation by histamine, human vascular endothelial cells (EC) shed a soluble form of tumour necrosis factor receptor 1 (sTNFR1) that binds up free TNF, dampening the inflammatory response. Shedding occurs through proteolytic cleavage of plasma membrane‐expressed TNFR1 catalysed by TNF‐α converting enzyme (TACE). Surface expressed TNFR1 on EC is largely sequestered into specific plasma membrane microdomains, the lipid rafts/caveolae. The purpose of this study was to determine the role of these domains in TACE‐mediated TNFR1 shedding in response to histamine. Human umbilical vein endothelial cells derived EA.hy926 cells respond to histamine via H1 receptors to shed TNFR1. Both depletion of cholesterol by methyl‐β‐cyclodextrin and small interfering RNA knockdown of the scaffolding protein caveolin‐1 (cav‐1), treatments that disrupt caveolae, reduce histamine‐induced shedding of membrane‐bound TNFR1. Moreover, immunoblotting of discontinuous sucrose gradient fractions show that TACE, such as TNFR1, is present within low‐density membrane fractions, concentrated within caveolae, in unstimulated EA.hy926 endothelial cells and co‐immunoprecipitates with cav‐1. Silencing of cav‐1 reduces the levels of both TACE and TNFR1 protein and displaces TACE, from low‐density membrane fractions where TNFR1 remains. In summary, we show that endothelial lipid rafts/caveolae co‐localize TACE to surface expressed TNFR1, promoting efficient shedding of sTNFR1 in response to histamine.
Induced psychosis after withdrawal of varenicline: a case report
Authors: López Arteaga María T. , Amo Carlos , Sánchez Morla Eva M. , Sánchez Román Marina
Published: June 2011

López Arteaga MT, Amo C, Sánchez Morla EM, Sánchez Román M. Induced psychosis after withdrawal of varenicline: a case report.

Objective: Varenicline has been associated with psychiatric side effects, and cases with psychotic symptoms during treatment have been reported, few of them after the withdrawal. We describe a case with no current or previous medical or psychiatric history.

Method: A single case report.

Results: The patient without previous psychiatric pathology, following the withdrawal of treatment with varenicline, experiences delirium and behavioural disturbances. There was a remission of symptoms after 3 weeks of treatment with risperidone.

Conclusion: Discontinuation of treatment with varenicline due to poor tolerance for side effects (nausea and insomnia) could trigger psychotic symptoms in subjects with no personal or family psychiatric history.
Preferred Information Sources for Clinical Decision Making: Critical Care Nurses’ Perceptions of Information Accessibility and Usefulness
Authors: Marshall Andrea P. , West Sandra H. , Aitken Leanne M.
Published: June 2011

Background: Variability in clinical practice may result from the use of diverse information sources to guide clinical decisions. In routine clinical practice, nurses privilege information from colleagues over more formal information sources. It is not clear whether similar information‐seeking behaviour is exhibited when critical care nurses make decisions about a specific clinical practice, where extensive practice variability exists alongside a developing research base.

Purpose: This study explored the preferred sources of information intensive care nurses used and their perceptions of the accessibility and usefulness of this information for making decisions in clinically uncertain situations specific to enteral feeding practice.

Methods: An instrumental case study design, incorporating concurrent verbal protocols, Q methodology and focus groups, was used to determine intensive care nurses’ perspectives of information use in the resolution of clinical uncertainty.

Findings: A preference for information from colleagues to support clinical decisions was observed. People as information sources were considered most useful and most accessible in the clinical setting. Text and electronic information sources were seen as less accessible, mainly because of the time required to access the information within the documents.

Discussion: When faced with clinical uncertainty, obtaining information from colleagues allows information to be quickly accessed and applied within the context of a specific clinical presentation. Seeking information from others also provides opportunities for shared decision‐making and potential validation of clinical judgment, although differing views may exacerbate clinical uncertainty.

Conclusions and Implications for Practice: The social exchange of clinical information may meet the needs of nurses working in a complex, time‐pressured environment but the extent of the evidence base for information passed through verbal communication is unclear. The perceived usefulness and accessibility of information is premised on the ease of use and access and thus the variability in information may be contributing to clinical uncertainty.
Emission sparks around M 81 and in some dwarf spheroidal galaxies
Authors: Karachentsev Igor , Kaisina Elena , Kaisin Serafim , Makarova Lidia
Published: June 2011

We use Hα images of three clumps of young stars situated between M 81 and NGC 3077 to estimate their star formation rate. Radial velocities of the clumps measured by us, as well as the velocity of the H ii region in the dwarf spheroidal (dSph) galaxy KDG 61, are compatible with their location at the outskirts of a large rotating gaseous disc around M 81. In contrast to KDG 61, the radial velocity of the emission knot in the dSph galaxy DDO 44, +213 ± 25 km s-1, tells us that this Hα spark belongs to the dSph galaxy itself. F475W and F814W images of DDO 44 extracted from the Hubble Space Telescope archive reveal eight bluish (B − I < 0.8) stars apparently associated with the Hα knot.
ESO 546-G34: the most-metal-poor, low surface brightness galaxy?
Authors: Mattsson Lars , Pilyugin Leonid S. , Bergvall Nils
Published: June 2011

We present a re-analysis of spectroscopic data for 23 H ii regions in 12 blue, metal-poor, low surface brightness galaxies (LSBGs), taking advantage of recent developments in calibrating strong-line methods. In doing so, we have identified a galaxy (ESO 546−G34) which may be the most-metal-poor LSBG found in the local Universe. Furthermore, we find evidence that blue, metal-poor LSBGs, together with blue compact galaxies (BCGs) and many other H ii galaxies, fall outside the regular luminosity—metallicity relation. This suggests that there might be an evolutionary connection between LSBGs and BCGs. In such cases, several very metal poor LSBGs should exist in the local Universe.
The G‐protein on cholesterol‐rich membrane microdomains mediates mucosal sensing of short‐ chain fatty acid and secretory response in rat colon
Authors: Yajima T. , Inoue R. , Yajima M. , Tsuruta T. , Karaki S. , Hira T. , Kuwahara A.
Published: June 2011

Aim:  Short‐chain fatty acids (SCFA) stimulate colonic contraction and secretion, which are mediated by an enteric reflex via a mucosal sensing and cholinergic mechanisms. The involvement of G‐protein signal transduction was examined in the secretory response to luminal propionate sensing in rat distal colon.

Methods:  Mucosa–submucosa and mucosa preparations were used to measure short‐circuit current (Isc) and acetylcholine (ACh) release respectively. Cholesterol‐rich membrane microdomains, lipid rafts/caveolae, were fractionated using a sucrose gradient ultra‐centrifugation after detergent‐free extraction of the isolated colonic crypt.

Results:  Luminal addition of methyl‐β‐cyclodextrin (10 mm) and mastoparan (30 μm), lipid rafts/caveolae disruptors, significantly inhibited luminal propionate‐induced (0.5 mm) increases in Isc, but did not affect increases in Isc induced by serosal ACh (0.05 mm) or electrical field stimulation (EFS). Luminal addition of YM–254890 (10 μm), a Gαq/11‐selective inhibitor, markedly inhibited propionate‐induced increase in Isc, but did not affect Isc responses to ACh and EFS. Both methyl‐β‐cyclodextrin and YM‐254890 significantly inhibited luminal propionate‐induced non‐neuronal release of ACh from colonocytes. Real‐time PCR demonstrated that in mRNA expression of SCFA receptors, GPR 43 was far higher than that of GPR41 in the colon. Western blotting analysis revealed that the cholesterol‐rich membrane microdomains that fractionated from colonic crypt cells were associated with caveolin‐1, flotillin‐1 and Gαq/11, but not GPR43. Uncoupling of Gαq/11 from flotillin‐1 in lipid rafts occurred under desensitization of the Isc response to propionate.

Conclusions:  These data demonstrate that the secretory response to luminal propionate in rat colon is mediated by G‐protein on cholesterol‐rich membrane microdomains, provably via Gαq/11.
Commonalities and Differences in the Research on Children’s Effortful Control and Executive Function: A Call for an Integrated Model of Self‐Regulation
Authors: Zhou Qing , Chen Stephen H. , Main Alexandra
Published: June 2011

Abstract— Effortful control (EC) and executive function (EF) are 2 constructs related to children’s self‐regulation that have historically been the subject of research in separate fields, with EC primarily the focus of temperament research and EF the focus of cognitive neuroscience and clinical psychology. This article selectively reviews and compares the EC and EF literature. The review indicates considerable similarities and overlaps in the definitions, core components, and measurement of EC and EF. Differences between the 2 literatures seem to primarily reflect differences in research focus as influenced by each field’s “tradition” rather than “real” differences in EC and EF as developmental constructs. Thus, developing an integrated theory of self‐regulation encompassing the EC and EF perspectives is critical for reducing overlap and confusion in future research. The article provides a number of recommendations on how to integrate the theory and methodology of EC and EF in future research for (a) the components and organization of self‐regulation, (b) the relation of self‐regulation to children’s adaptive functions, (c) the neurological basis of self‐regulation and its development, and (d) the development and evaluation of interventions targeting children’s self‐regulation.
Patient Diaries As a Clinical Endpoint in Parkinson's Disease Clinical Trials
Authors: Papapetropoulos Spyridon (Spyros)
Published: June 2011

Parkinson's disease (PD) is the second most common neurodegenerative disorder with an estimated 4 million patients worldwide. L‐dopa is standard, and often initial, therapy for patients with this condition; however, with continued dopaminergic treatment and as the disease progresses, the majority of patients experience complications such as “wearing‐off” symptoms, dyskinesias, and other motor complications. These complications may become disabling and profoundly affect quality of life. Treatment modification and combination therapies with L‐dopa, dopamine agonists, monoamine oxidase type B inhibitors, and catechol‐O‐methyltransferase inhibitors are commonly used to manage complications. In recent years regulatory agencies, clinical researchers, and sponsors have widely accepted and utilized changes in “ON” and “OFF” time measured by Patient Hauser Diaries as endpoints for measuring efficacy of therapeutics seeking approval for symptomatic treatment of PD. Successful antiparkinsonian medications have been associated with treatment effects of more than 1 h in either reduction of “OFF” time of increase in “ON” time. Accurate “ON” and “OFF” time registration during clinical studies requires rigorous patient training. Reduced compliance, recall bias and diary fatigue are common problems seen with patient diary reported measures. Electronic diaries may help reducing some of these problems but may be associated with other challenges in large, multicenter studies.
On the contribution of group III and IV muscle afferents to the circulatory response to rhythmic exercise in humans
Authors: Amann Markus , Runnels Sean , Morgan David E. , Trinity Joel D. , Fjeldstad Anette S. , Wray D. Walter , Reese Van R. , Richardson Russell S.
Published: June 2011

Non‐technical summary We investigated the role of thin fibre muscle afferents in the circulatory response to exercise in humans. The results not only document the importance of continuous afferent feedback from working human skeletal muscle to achieve appropriate haemodynamic and ventilatory responses to exercise but also suggest that the relative contribution of this mechanism is larger than traditionally accepted.
Application of Carbon Nanotubes to Thermal Interface Materials
Authors: Fabris Drazen , Rosshirt Michael , Cardenas Christopher , Wilhite Patrick , Yamada Toshishige , Yang Cary Y.
Published: June 2011

Improvements in thermal interface materials (TIMs) can enhance heat transfer in electronics packages and reduce high temperatures. TIMs are generally composed of highly conductive particle fillers and a matrix that allows for good surface wetting and compliance of the material during application. Two types of TIMs are tested based on the addition of carbon nanotubes (CNTs): one mixed with a commercial TIM product and the other only CNTs and silicone oil. The materials are tested using an in-house apparatus that allows for the simultaneous measurement of temperature, pressure, heat flux, and TIM thickness. Results show that addition of large quantities of CNTs degrades the performance of the commercial TIM, while the CNT-silicone oil mixtures showed improved performance at high pressures. Thickness and pressure measurements indicate that the CNT-thermal grease mixtures are more compliant, with a small increase in bulk thermal conductivity over the range of tested pressures.
Experimental Study of Near-Field Entrainment of Moderately Overpressured Jets
Authors: Solovitz Stephen A. , Mastin Larry G. , Saffaraval Farhad
Published: June 2011

Particle image velocimetry (PIV) experiments have been conducted to study the velocity flow fields in the developing flow region of high-speed jets. These velocity distributions were examined to determine the entrained mass flow over a range of geometric and flow conditions, including overpressured cases up to an overpressure ratio of 2.83. In the region near the jet exit, all measured flows exhibited the same entrainment up until the location of the first shock when overpressured. Beyond this location, the entrainment was reduced with increasing overpressure ratio, falling to approximately 60% of the magnitudes seen when subsonic. Since entrainment ratios based on lower speed, subsonic results are typically used in one-dimensional volcanological models of plume development, the current analytical methods will underestimate the likelihood of column collapse. In addition, the concept of the entrainment ratio normalization is examined in detail, as several key assumptions in this methodology do not apply when overpressured.
Experimental Evidence of Rotating Stall in a Pump-Turbine at Off-Design Conditions in Generating Mode
Authors: Hasmatuchi Vlad , Farhat Mohamed , Roth Steven , Botero Francisco , Avellan François
Published: June 2011

An experimental investigation of the rotating stall in reduced scale model of a low specific speed radial pump-turbine at runaway and turbine brake conditions in generating mode is achieved. Measurements of wall pressure in the stator are performed along with high-speed flow visualizations in the vaneless gap with the help of air bubbles injection. When starting from the best efficiency point (BEP) and increasing the impeller speed, a significant increase of the pressure fluctuations is observed mainly in the wicket gates channels. The spectral analysis shows a rise of a low frequency component (about 70% of the impeller rotational frequency) at runaway, which further increases as the zero discharge condition is approached. Analysis of the instantaneous pressure peripheral distribution in the vaneless gap reveals one stall cell rotating with the impeller at sub-synchronous speed. High-speed movies reveal a quite uniform flow pattern in the guide vanes channels at the normal operating range, whereas at runaway the flow is highly disturbed by the rotating stall passage. The situation is even more critical at very low positive discharge, where backflow and vortices in the guide vanes channels develop during the stall cell passage. A specific image processing technique is applied to reconstruct the rotating stall evolution in the entire guide vanes circumference for a low positive discharge operating point. The findings of this study suggest that one stall cell rotates with the impeller at sub-synchronous velocity in the vaneless gap between the impeller and the guide vanes. It is the result of rotating flow separations developed in several consecutive impeller channels which lead to their blockage.
The cis-Regulatory Logic of Hedgehog Gradient Responses: Key Roles for Gli Binding Affinity, Competition, and Cooperativity
Authors: Parker David S. , White Michael A. , Ramos Andrea I. , Cohen Barak A. , Barolo Scott
Published: June 2011

Reporter gene assays in
Drosophila
and modeling reveal mechanisms that control transcriptional responses to gradients of Hedgehog ligands.
Novel Pentadecenyl Tetrazole Enhances Susceptibility of Methicillin-Resistant
Staphylococcus aureus
Biofilms to Gentamicin
Authors: Olson Krista M. , Starks Courtney M. , Williams Russell B. , O'Neil-Johnson Mark , Huang Zhongping , Ellis Michael , Reilly John E. , Eldridge Gary R.
Published: June 2011

One method that bacteria employ to reduce their susceptibility to antibiotics is the formation of biofilms. We developed a robust 6-well plate biofilm assay to evaluate early-stage discovery compounds against methicillin-resistant
Staphylococcus aureus
(MRSA). Tissue culture-treated 6-well plates were selected for this assay because they facilitate the adherence of MRSA and enable accurate determination of the number of CFU in each well. The MRSA biofilms formed in this assay exhibit increased tolerances to clinically used antibiotics. Using this biofilm assay, we identified a novel potentiator of gentamicin against MRSA biofilms. The combination of gentamicin and pentadecenyl tetrazole is superior to clinically used MRSA antibiotics against these MRSA biofilms. This novel combination also exhibits synergistic effects on MRSA planktonic cells. This plant-derived compound reveals promise for its effectiveness and warrants further lead optimization as an antibiotic and aminoglycoside potentiator.
Expression of a Clostridium perfringens Type IV Pilin by Neisseria gonorrhoeae Mediates Adherence to Muscle Cells
Authors: Rodgers Katherine , Arvidson Cindy Grove , Melville Stephen
Published: June 2011

Clostridium perfringens
is an anaerobic, Gram-positive bacterium that causes a range of diseases in humans, including lethal gas gangrene. We have recently shown that strains of
C. perfringens
move across the surface of agar plates by a unique type IV pilus (TFP)-mediated social motility that had not been previously described. Based on sequence homology to pilins in Gram-negative bacteria,
C. perfringens
appears to have two pilin subunits, PilA1 and PilA2. Structural prediction analysis indicated PilA1 is similar to the pseudopilin found in
Klebsiella oxytoca
, while PilA2 is more similar to true pilins found in the Gram-negative pathogens
Pseudomonas aeruginosa
and
Neisseria gonorrhoeae
. Strains of
N. gonorrhoeae
that were genetically deficient in the native pilin, PilE, but supplemented with inducible expression of PilA1 and PilA2 of
C. perfringens
were constructed. Genetic competence, wild-type twitching motility, and attachment to human urogenital epithelial cells were not restored by expression of either pilin. However, attachment to mouse and rat myoblast (muscle) cell lines was observed with the
N. gonorrhoeae
strain expressing PilA2. Significantly, wild-type
C. perfringens
cells adhered to mouse myoblasts under anaerobic conditions, and adherence was 10-fold lower in a
pilT
mutant that lacked functional TFP. These findings implicate
C. perfringens
TFP in the ability of
C. perfringens
to adhere to and move along muscle fibers
in vivo
, which may provide a therapeutic approach to limiting this rapidly spreading and highly lethal infection.
Relative Efficacy of Uptake and Presentation of Mycobacterium bovis BCG Antigens by Type I Mouse Lung Epithelial Cells and Peritoneal Macrophages
Authors: Kumari Mandavi , Saxena Rajiv K.
Published: June 2011

Flow cytometric studies indicated that both peritoneal macrophages (PMs) and primary lung epithelial (PLE) cells isolated from mouse lungs could take up fluorescence-taggedMycobacterium bovisBCG. BCG uptake in both cases was significantly inhibited by cytochalasin D, indicating active internalization of BCG by these cells. Confocal microscopy data further confirmed that BCG was internalized by PLE cells. BCG sonicate antigen (sBCG) had marked toxicity toward PMs but was relatively nontoxic to PLE cells. Accordingly, BCG sonicate antigen induced a significantly higher apoptotic and necrotic response in PMs compared to that in PLE cells. Both PMs and PLE cells exposed to BCG antigens and fixed thereafter could efficiently present antigens to purified BCG-sensitized T helper cells, as assessed by the release of interleukin-2 (IL-2) and gamma interferon (IFN-γ). If, however, PLE cells were fixed before exposure to BCG, antigen presentation was abrogated, indicating that the PLE cells may in some way process the BCG antigen. A comparison of efficacies of BCG-pulsed PLE cells and PMs to present antigen at various antigen-presenting cell (APC)/T cell ratios indicated that PMs had only marginally greater APC function than that of PLE cells. Staining with specific monoclonal antibodies indicated that the cultured PLE cells used for antigen presentation essentially comprised type I epithelial cells. Our results suggest that type I lung epithelial cells may present BCG antigens to sensitized T helper cells and that their performance as APCs is comparable with that of PMs.
Capturing paediatric injury in Ontario: differences in injury incidence using self-reported survey and health service utilisation data
Authors: White Heather L , Macpherson Alison K
Published: June 2011

Objective

Population-based health surveys are increasingly popular sources of data on injury occurrence. Self-reported surveys can yield estimates of the total incidence of non-fatal injuries while simultaneously capturing a rich repository of contextual data that may be informative for exploring determinants of injury risk. Although survey data are rarely recognised as complete, several researchers have expressed concerns about the sensitivity and validity of self-reported injury data, questioning whether captured cases are representative of the population experience of injury, particularly among children and youth. The present study sought to compare the population incidence of paediatric injury estimated from self-reported survey responses to those documented by a complete-capture health service utilisation database among Ontario children.

Methods

Injury incidence rates documented from the National Longitudinal Survey of Children and Youth and the National Population Health Survey were compared with those reported in Canada's National Ambulatory Care Reporting System for Ontario youth aged 0–19 years for fiscal year 2002/3, stratified by the child's age and geographical location of residence.

Results

The two self-reported health surveys underestimated the population incidence of injury among Ontario children by at least 49% and 53%, respectively. Systematic errors exist in survey data capture such that injuries in infants and preschoolers (<4 years of age) and urban residents were most likely to be missed by the population health surveys.

Conclusion

Injury incidence estimated through self-report is not representative of the population burden and experience of paediatric injury for Ontario children, and may produce biased estimates of risk when analysed as independent sources of data.
FINITE DIMENSIONAL STRUCTURE OF THE GPI DISCHARGE IN PATIENTS WITH PARKINSON'S DISEASE
Authors: ANDRES DANIELA SABRINA , CERQUETTI DANIEL , MERELLO MARCELO
Published: June 2011

Stochastic systems are infinitely dimensional and deterministic systems are low dimensional, while real systems lie somewhere between these two limit cases. If the calculation of a low (finite) dimension is in fact possible, one could conclude that the system under study is not purely random. In the present work we calculate the maximal Lyapunov exponent from interspike intervals time series recorded from the internal segment of the Globus Pallidusfrom patients with Parkinson's disease. We show the convergence of the maximal Lyapunov exponent at a dimension equal to 7 or 8, which is therefore our estimation of the embedding dimension for the system. For dimensions below 7 the observed behavior is what would be expected from a stochastic system or a complex system projecting onto lower dimensional spaces. The maximal Lyapunov exponent did not show any differences between tremor and akineto-rigid forms of the disease. However, it did decay with the value of motor Unified Parkinson's Disease Rating Scale -OFF scores. Patients with a more severe disease (higher UPDRS-OFF score) showed a lower value of the maximal Lyapunov exponent. Taken together, both indexes (the maximal Lyapunov exponent and the embedding dimension) remark the importance of taking into consideration the system's non-linear properties for a better understanding of the information transmission in the basal ganglia.
FOREGROUND DETECTION IN VIDEO SEQUENCES WITH PROBABILISTIC SELF-ORGANIZING MAPS
Authors: LÓPEZ-RUBIO EZEQUIEL , LUQUE-BAENA RAFAEL MARCOS , DOMÍNGUEZ ENRIQUE
Published: June 2011

Background modeling and foreground detection are key parts of any computer vision system. These problems have been addressed in literature with several probabilistic approaches based on mixture models. Here we propose a new kind of probabilistic background models which is based on probabilistic self-organising maps. This way, the background pixels are modeled with more flexibility. On the other hand, a statistical correlation measure is used to test the similarity among nearby pixels, so as to enhance the detection performance by providing a feedback to the process. Several well known benchmark videos have been used to assess the relative performance of our proposal with respect to traditional neural and non neural based methods, with favourable results, both qualitatively and quantitatively. A statistical analysis of the differences among methods demonstrates that our method is significantly better than its competitors. This way, a strong alternative to classical methods is presented.
EXPLORATION OF THE MEMORY EFFECT ON THE PHOTON-ASSISTED TUNNELING VIA A SINGLE QUANTUM DOT: A GENERALIZED FLOQUET THEORETICAL APPROACH
Authors: CHEN HSING-TA , HO TAK-SAN , CHU SHIH-I
Published: June 2011

The generalized Floquet approach is developed to study memory effect on electron transport phenomena through a periodically driven single quantum dot in an electrode–multi-level dot–electrode nanoscale quantum device. The memory effect is treated using a multi-function Lorentzian spectral density (LSD) model that mimics the spectral density of each electrode in terms of multiple Lorentzian functions. For the symmetric single-function LSD model involving a single-level dot, the underlying single-particle propagator is shown to be related to a 2×2 effective time-dependent Hamiltonian that includes both the periodic external field and the electrode memory effect. By invoking the generalized Van Vleck (GVV) nearly degenerate perturbation theory, an analytical Tien-Gordon-like expression is derived for arbitrary order multi-photon resonance d.c. tunneling current. Numerically converged simulations and the GVV analytical results are in good agreement, revealing the origin of multi-photon coherent destruction of tunneling and accounting for the suppression of the staircase jumps of d.c. current due to the memory effect. Specially, a novel blockade phenomenon is observed, showing distinctive oscillations in the field-induced current in the large bias voltage limit.
A SELF-ADAPTABLE INDOOR LOCALIZATION SCHEME FOR WIRELESS SENSOR NETWORKS
Authors: YANG CHI-LU , CHANG YEIM-KUAN , CHEN YU-TSO , CHU CHIH-PING , CHEN CHI-CHANG
Published: June 2011

Service systems used for various applications in home automation and security require estimating the locations precisely using certain sensors. Serving a mobile user automatically by sensing his/her locations in an indoor environment is considered as a challenge. However, indoor localization cannot be carried out effectively using the Global Positioning System (GPS). In recent years, the use of Wireless Sensor Networks (WSNs) in locating a mobile object in an indoor environment has become popular. Some physical features have also been discussed to solve localization in WSNs. In this paper, we inquire into received signal strength indication (RSSI)-based solutions and propose a new localization scheme called the closer tracking algorithm (CTA) for indoor localization. Under the proposed CTA, a mechanism on mode-change is designed to switch automatically between the optimal approximately closer approach (ACA) and the real-time tracking (RTT) method according to pre-tuned thresholds. Furthermore, we design a mechanism to move reference nodes dynamically to reduce the uncovered area of the ACA for increasing the estimation accuracy. We evaluate the proposed CTA using ZigBee CC2431 modules. The experimental results show that the proposed CTA can determine the position accurately with an error distance less than 0.9 m. At the same time, the CTA scheme has at least 87% precision when the distance is less than 0.9 m. The proposed CTA can select an adaptive mode properly to improve the localization accuracy with high confidence. Moreover, the experimental results also show that the accuracy can be improved by the deployment and movement of reference nodes.
A TEST CASE PRIORITIZATION BASED ON DEGREE OF RISK EXPOSURE AND ITS EMPIRICAL STUDY
Authors: YOON HOIJIN , CHOI BYOUNGJU
Published: June 2011

We propose a test case prioritization strategy for risk based testing, in which the risk exposure is employed as the key criterion of evaluation. Existing approaches to risk based testing typically employ risk exposure values as assessed by the tester. In contrast, we employ exposure values that have been determined by experts during the risk assessment stage of the risk management process. If a given method produces greater accuracy in fault detection, that approach is considered more valuable for software testing. We demonstrate the value of our proposed risk based testing method in this sense through its application.
ASIAN AMERICAN-FOUNDED VENTURES IN SILICON VALLEY: CHALLENGES, STRATEGIC PARTNERSHIP, AND PERFORMANCE
Authors: CHOI DAVID Y. , CHEN DONG , LEE WOO JIN
Published: June 2011

This paper examines the performance of Silicon Valley ventures with Asian-American founding teams. We review some challenges faced by these ventures, compare their performance with that of other ventures, and analyze the impact of strategic partnerships on their performance. Our results indicate that firms founded by Asian American entrepreneurs tend to require more time to reach initial public offering (IPO) status than do other ventures in Silicon Valley. Our results further show that, despite needing this extra time, Asian American-founded ventures significantly outperformed their counterparts in 12-month post-IPO share price gain. This superior short-term post-IPO performance suggests that Asian American firms, particularly those that lacked relationships with U.S.-based strategic investors, might have been undervalued prior to and at IPO.
CHALLENGES IN FEMALE ENTREPRENEURIAL DEVELOPMENT — A CASE ANALYSIS OF NIGERIAN ENTREPRENEURS
Authors: SINGH SATWINDER , MORDI CHIMA , OKAFOR CHINONYE , SIMPSON RUTH
Published: June 2011

The paper examines the validity of stereotypical image of challenges female entrepreneurs (FE) encounter in the development of their business. The study which is conducted in the context of Nigeria, a large transition economy, throws light on a number of general and culture-dominated issues specific to traditional societies. FE, particularly those coming from self-employed parental households, are good at acquiring education and training in their line of business and work much harder at it. However, they struggle to balance family and work life, a job that is made difficult owing to lack of recognition from spouse and business groups they deal with, gender discrimination and sexual harassment. Religious values and previous work experience comes out a positive factor in dealing with challenges. Policy recommendations for the government lie in the identification of potential FE and providing them with necessary training and assistance and key inputs necessary for the growth of a business.
Function Spaces with a Random Variable Exponent
Authors: Tian Boping , Fu Yongqiang , Xu Bochi
Published: June 2011

The spaces with a random variable exponent Lp(ω)(D × Ω) and
Wk,p(ω)(D × Ω) are introduced. After discussing the properties of the spaces
Lp(ω)(D × Ω) and Wk,p(ω)(D × Ω), we give an application of these spaces to the stochastic partial differential equations with random variable growth.