bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of radixin in altered localization of canalicular conjugate export pump Mrp2 in cholestatic rat liver
Authors: Kojima Hideyuki , Sakurai Shinya , Yoshiji Hitoshi , Uemura Masahito , Yoshikawa Masahide , Fukui Hiroshi
Published: August 2007

Aim:  Cholestasis has been associated with the endocytic retrieval of multidrug resistance protein 2 (Mrp2), but its mechanism is still unclear. Recent studies have indicated that radixin, a cross‐linker between the actin filaments and membrane proteins, may be activated by phosphorylation and may be required for the canalicular localization of Mrp2.

Methods:  We investigated the role of radixin in the altered localization of Mrp2 in rat models of intrahepatic (ethinyl estradiol treatment) and extrahepatic (bile duct ligation) cholestasis using immunofluorescence microscopy. The changes in localization and expression were analyzed using Scion Image for Windows.

Results:  In both models, Mrp2 was localized outside as well as inside the ZO‐1 staining, indicating partial dislocation from the canalicular membrane. In contrast to the steep elevation of the immunostaining intensity curves for Mrp2 in the controls, the corresponding curves in both models were broadened and flattened, confirming endocytic retrieval into the hepatocytes. Mrp2 and radixin were colocalized at the canalicular domain in the controls, whereas in both cholestatic rats they were dissociated at some canaliculi, indicating the disturbed colocalization of Mrp2 and radixin in cholestasis. The fluorescence of phosphorylated radixin, an active form of radixin, markedly decreased in both cholestatic models, which was supported by the reduced peak fluorescence intensities.

Conclusion:  The disturbed colocalization of Mrp2 and radixin may contribute to the endocytic retrieval of Mrp2 in cholestasis due to the failure to anchor Mrp2 in the canalicular membrane, in which the phosphorylated radixin may play a major role.
Caring and Internality
Authors: JAWORSKA AGNIESZKA
Published: August 2007

In his work on internality, identification, and caring, Harry Frankfurt attempts to delineate the organization of agency peculiar to human beings, while avoiding the traditional overintellectualized emphasis on the human capacity to reason about action. The focal point of Frankfurt’s alternative picture is our capacity to make our own motivation the object of reflection. Building upon the observation that marginal agents (such as young children and Alzheimer’s patients) are capable of caring, I show that neither caring nor internality need to depend on the phenomena of reflectiveness. I develop alternative interlocking accounts of caring and internality that are independent of both reflectiveness and evaluation, but that can still do justice to the central role of carings in the organization of agency characteristic of human persons.
Pulmonary versus Systemic Delivery of Antibiotics: Comparison of Vancomycin Dispositions in the Isolated Rat Lung
Authors: de Jesús Valle María José , López Francisco González , Hurlé Alfonso Domínguez-Gil , Navarro Amparo Sánchez
Published: August 2007

Vancomycin dispositions in the respiratory system were compared after systemic and inhalatory administration under two respiratory conditions using the isolated-lung model. Inhalatory delivery led to much higher drug levels in pulmonary tissue and fluids. The respiratory pattern affects vancomycin disposition in the pulmonary system regardless of the administration route.
Genetic Analysis of the Dihydrofolate Reductase-Thymidylate Synthase Gene from Geographically Diverse Isolates of
Plasmodium malariae
Authors: Tanomsing Naowarat , Imwong Mallika , Pukrittayakamee Sasithon , Chotivanich Kesinee , Looareesuwan Sornchai , Mayxay Mayfong , Dolecek Christiane , Hien Tran Tinh , do Rosario Virgilio E. , Arez Ana Paula , Michon Pascal , Snounou Georges , White Nicholas J. , Day Nicholas P. J.
Published: August 2007

Plasmodium malariae
, the parasite responsible for quartan malaria, is transmitted in most areas of malaria endemicity and is associated with significant morbidity. The sequence of the gene coding for the enzyme dihydrofolate reductase-thymidylate synthase (DHFR-TS) was obtained from field isolates of
P. malariae
and from the closely related simian parasite
Plasmodium brasilianum
. The two sequences were nearly 100% homologous, adding weight to the notion that they represent genetically distinct lines of the same species. A survey of polymorphisms of the
dhfr
sequences in 35 isolates of
P. malariae
collected from five countries in Asia and Africa revealed a low number of nonsynonymous mutations in five codons. In five of the isolates collected from southeast Asia, a nonsynonymous mutation was found at one of the three positions known to be associated with antifolate resistance in other
Plasmodium
species. Five isolates with the wild-type DHFR could be assayed for drug susceptibility in vitro and were found to be sensitive to pyrimethamine (mean 50% inhibitory concentration, 2.24 ng/ml [95% confidence interval, 0.4 to 3.1]).
Antiproliferative Effect of Dihydroxyacetone on
Trypanosoma brucei
Bloodstream Forms: Cell Cycle Progression, Subcellular Alterations, and Cell Death
Authors: Uzcátegui Néstor L. , Carmona-Gutiérrez Didac , Denninger Viola , Schoenfeld Caroline , Lang Florian , Figarella Katherine , Duszenko Michael
Published: August 2007

We evaluated the effects of dihydroxyacetone (DHA) on
Trypanosoma brucei
bloodstream forms. DHA is considered an energy source for many different cell types.
T. brucei
takes up DHA readily due to the presence of aquaglyceroporins. However, the parasite is unable to use it as a carbon source because of the absence of DHA kinase (DHAK). We could not find a homolog of the relevant gene in the genomic database of
T. brucei
and have been unable to detect DHAK activity in cell lysates of the parasite, and the parasite died quickly if DHA was the sole energy source in the medium. In addition, during trypanosome cultivation, DHA induced growth inhibition with a 50% inhibitory concentration of about 1 mM, a concentration that is completely innocuous to mammals. DHA caused cell cycle arrest in the G
2
/M phase of up to 70% at a concentration of 2 mM. Also, DHA-treated parasites showed profound ultrastructural alterations, including an increase of vesicular structures within the cytosol and the presence of multivesicular bodies, myelin-like structures, and autophagy-like vacuoles, as well as a marked disorder of the characteristic mitochondrion structure. Based on the toxicity of DHA for trypanosomes compared with mammals, we consider DHA a starting point for a rational design of new trypanocidal drugs.
Phase 2 Study of Ceftaroline versus Standard Therapy in Treatment of Complicated Skin and Skin Structure Infections
Authors: Talbot George H. , Thye Dirk , Das Anita , Ge Yigong
Published: August 2007

Ceftaroline, the bioactive metabolite of ceftaroline fosamil (previously PPI-0903, TAK-599), is a broad-spectrum cephalosporin with potent in vitro activity against multidrug-resistant gram-positive aerobic pathogens, including methicillin-resistant
Staphylococcus aureus
. A randomized, observer-blinded study to evaluate the safety and efficacy of ceftaroline versus standard therapy in treating complicated skin and skin structure infections (cSSSI) was performed. Adults with cSSSI, including at least one systemic marker of inflammation, were randomized (2:1) to receive intravenous (i.v.) ceftaroline (600 mg every 12 h) or i.v. vancomycin (1 g every 12 h) with or without adjunctive i.v. aztreonam (1 g every 8 h) for 7 to 14 days. The primary outcome measure was the clinical cure rate at a test-of-cure (TOC) visit 8 to 14 days after treatment. Secondary outcomes included the microbiological success rate (eradication or presumed eradication) at TOC and the clinical relapse rate 21 to 28 days following treatment. Of 100 subjects enrolled, 88 were clinically evaluable; the clinical cure rate was 96.7% (59/61) for ceftaroline versus 88.9% (24/27) for standard therapy. Among the microbiologically evaluable subjects (i.e., clinically evaluable and having had at least one susceptible pathogen isolated at baseline), the microbiological success rate was 95.2% (40/42) for ceftaroline versus 85.7% (18/21) for standard therapy. Relapse occurred in one subject in each group (ceftaroline, 1.8%; standard therapy, 4.3%). Ceftaroline exhibited a very favorable safety and tolerability profile, consistent with that of marketed cephalosporins. Most adverse events from ceftaroline were mild and not related to treatment. Ceftaroline holds promise as a new therapy for treatment of cSSSI and other serious polymicrobial infections.
Contributions of the Combined Effects of Topoisomerase Mutations toward Fluoroquinolone Resistance in
Escherichia coli
Authors: Morgan-Linnell Sonia K. , Zechiedrich Lynn
Published: August 2007

In defined, isogenic strains, at least three mutations, two of which must be in
gyrA
, were required to exceed the CLSI breakpoint for fluoroquinolone resistance. Strains with double mutations in both
gyrA
and
parC
had even higher MICs of fluoroquinolones than strains with totals of three mutations.
Targeted Intranasal Mupirocin To Prevent Colonization and Infection by Community-Associated Methicillin-Resistant
Staphylococcus aureus
Strains in Soldiers: a Cluster Randomized Controlled Trial
Authors: Ellis Michael W. , Griffith Matthew E. , Dooley David P. , McLean Joseph C. , Jorgensen James H. , Patterson Jan E. , Davis Kepler A. , Hawley Joshua S. , Regules Jason A. , Rivard Robert G. , Gray Paula J. , Ceremuga Julia M. , DeJoseph Mary A. , Hospenthal Duane R.
Published: August 2007

Community-associated methicillin-resistant
Staphylococcus aureus
(CA-MRSA) is an emerging pathogen that primarily manifests as uncomplicated skin and soft tissue infections. We conducted a cluster randomized, double-blind, placebo-controlled trial to determine whether targeted intranasal mupirocin therapy in CA-MRSA-colonized soldiers could prevent infection in the treated individual and prevent new colonization and infection within their study groups. We screened 3,447 soldiers comprising 14 training classes for CA-MRSA colonization from January to December 2005. Each training class was randomized to either the mupirocin or placebo study group, and the participants identified as CA-MRSA colonized were treated with either mupirocin or placebo. All participants underwent repeat screening after 8 to 10 weeks and were monitored for 16 weeks for development of infection. Of 3,447 participants screened, 134 (3.9%) were initially colonized with CA-MRSA. Five of 65 (7.7%; 95% confidence interval [95% CI], 4.0% to 11.4%) placebo-treated participants and 7 of 66 (10.6%; 95% CI, 7.9% to 13.3%) mupirocin-treated participants developed infections; the difference in the infection rate of the placebo- and mupirocin-treated groups was −2.9% (95% CI, −7.5% to 1.7%). Of those not initially colonized with CA-MRSA, 63 of 1,459 (4.3%; 95% CI, 2.7% to 5.9%) of the placebo group and 56 of 1,607 (3.5%; 95% CI, 2.6% to 5.2%) of the mupirocin group developed infections; the difference in the infection rate of the placebo and mupirocin groups was 0.8% (95% CI, −1.0% to 2.7%). Of 3,447 participants, 3,066 (89%) were available for the second sampling and completed follow-up. New CA-MRSA colonization occurred in 24 of 1,459 (1.6%; 95% CI, 0.05% to 2.8%) of the placebo group participants and 23 of 1,607 (1.4%; 95% CI, 0.05% to 2.3%) of the mupirocin group participants; the difference in the infection rate of the placebo and mupirocin groups was 0.2% (95% CI, −1.3% to 1.7%). Despite CA-MRSA eradication in colonized participants, this study showed no decrease in infections in either the mupirocin-treated individuals or within their study group. Furthermore, CA-MRSA eradication did not prevent new colonization within the study group.
Identification ofFrancisella tularensis Himar1-Based Transposon Mutants Defective for Replication in Macrophages
Authors: Maier Tamara M. , Casey Monika S. , Becker Rachel H. , Dorsey Caleb W. , Glass Elizabeth M. , Maltsev Natalia , Zahrt Thomas C. , Frank Dara W.
Published: August 2007

Francisella tularensis, the etiologic agent of tularemia in humans, is a potential biological threat due to its low infectious dose and multiple routes of entry.F. tularensisreplicates within several cell types, eventually causing cell death by inducing apoptosis. In this study, a modifiedHimar1transposon (HimarFT) was used to mutagenizeF. tularensisLVS. Approximately 7,000 Kmrclones were screened using J774A.1 macrophages for reduction in cytopathogenicity based on retention of the cell monolayer. A total of 441 candidates with significant host cell retention compared to the parent were identified following screening in a high-throughput format. Retesting at a defined multiplicity of infection followed by in vitro growth analyses resulted in identification of approximately 70 candidates representing 26 unique loci involved in macrophage replication and/or cytotoxicity. Mutants carrying insertions in seven hypothetical genes were screened in a mouse model of infection, and all strains tested appeared to be attenuated, which validated the initial in vitro results obtained with cultured macrophages. Complementation and reverse transcription-PCR experiments suggested that the expression of genes adjacent to theHimarFTinsertion may be affected depending on the orientation of the constitutivegroELpromoter region used to ensure transcription of the selective marker in the transposon. A hypothetical gene, FTL_0706, postulated to be important for lipopolysaccharide biosynthesis, was confirmed to be a gene involved in O-antigen expression inF. tularensisLVS and Schu S4. These and other studies demonstrate that therapeutic targets, vaccine candidates, or virulence-related genes may be discovered utilizing classical genetic approaches inFrancisella.
Overproduction of DNA Adenine Methyltransferase Alters Motility, Invasion, and the Lipopolysaccharide O-Antigen Composition of
Yersinia enterocolitica
Authors: Fälker Stefan , Schilling Jennifer , Schmidt M. Alexander , Heusipp Gerhard
Published: August 2007

DNA adenine methyltransferase (Dam) not only regulates basic cellular functions but also interferes with the proper expression of virulence factors in various pathogens. We showed previously that for the human pathogen
Yersinia enterocolitica
, overproduction of Dam results in increased invasion of epithelial cells. Since invasion and motility are coordinately regulated in
Y. enterocolitica
, we analyzed the motility of a Dam-overproducing (Dam
OP
) strain and found it to be highly motile. In Dam
OP
strains, the operon encoding the master regulator of flagellum biosynthesis,
flhDC
, is upregulated. We show that the increased invasion is not due to enhanced expression of known and putative
Y. enterocolitica
invasion and adhesion factors, such as Inv, YadA, Ail, Myf fibrils, Pil, or Flp pili. However, overproduction of Dam no longer results in increased invasion for an
inv
mutant strain, indicating that Inv is necessary for increased invasion after overproduction of Dam. Since we show that overproduction of Dam results in an increased amount of rough lipopolysaccharide (LPS) molecules lacking O-antigen side chains, this implies that reduced steric hindrance by LPS might contribute to increased invasion by a
Y. enterocolitica
Dam
OP
strain. Our data add an important new aspect to the various virulence-associated phenotypes influenced by DNA methylation in
Y. enterocolitica
and indicate that Dam targets regulatory processes modulating the composition and function of the bacterial surface.
Mannheimia haemolytica
Leukotoxin Binds to Lipid Rafts in Bovine Lymphoblastoid Cells and Is Internalized in a Dynamin-2- and Clathrin-Dependent Manner
Authors: Atapattu Dhammika N. , Czuprynski Charles J.
Published: August 2007

Mannheimia haemolytica
is the principal bacterial pathogen of the bovine respiratory disease complex. Its most important virulence factor is a leukotoxin (LKT), which is a member of the RTX family of exotoxins produced by many gram-negative bacteria. Previous studies demonstrated that LKT binds to the β
2
-integrin LFA-1 (CD11a/CD18) on bovine leukocytes, resulting in cell death. In this study, we demonstrated that depletion of lipid rafts significantly decreases LKT-induced bovine lymphoblastoid cell (BL-3) death. After binding to BL-3 cells, some of the LKT relocated to lipid rafts in an LFA-1-independent manner. We hypothesized that after binding to LFA-1 on BL-3 cells, LKT moves to lipid rafts and clathrin-coated pits via a dynamic process that results in LKT internalization and cytotoxicity. Knocking down dynamin-2 by small interfering RNA reduced both LKT internalization and cytotoxicity. Similarly, expression of dominant negative Eps15 protein expression, which is required for clathrin coat formation, reduced LKT internalization and LKT-mediated cytotoxicity to BL-3 cells. Finally, we demonstrated that inhibiting actin polymerization reduced both LKT internalization and LKT-mediated cytotoxicity. These results suggest that both lipid rafts and clathrin-mediated mechanisms are important for LKT internalization and cytotoxicity in BL-3 cells and illustrate the complex nature of LKT internalization by the cytoskeletal network.
Rapid Elimination ofToxoplasma gondiiby Gamma Interferon-Primed Mouse Macrophages Is Independent of CD40 Signaling
Authors: Zhao Yanlin , Wilson Douglas , Matthews Suzanne , Yap George S.
Published: August 2007

Autophagy has been implicated in the intracellular destruction ofToxoplasma gondiiby primed macrophages following gamma interferon (IFN-γ) activation of p47 GTPases. CD40 ligation has also been shown to trigger autophagic elimination ofT. gondiiindependent of IFN-γ and p47 GTPases. Here we demonstrate that IFN-γ/p47 GTPase-dependent elimination ofT. gondiiby strain CPS vaccine-primed macrophages is independent of CD40/tumor necrosis factor signaling. Similar to wild-type controls, both CD40-deficient and tumor necrosis factor receptor 1/2 (TNFR1/2)-deficient macrophages can efficiently eliminate invaded strain GFP-PTG and restrain its replication following priming. In contrast, macrophages from mice lacking the IFN-γ receptor gene neither clear the parasites nor repress their proliferation. Thus, CD40 and IFN-γ-induced pathogen elimination might represent two independent resistance pathways, the latter of which plays a primary role in anti-Toxoplasmaimmunity in mice.
Quantification of the physiological and performance characteristics of on-court tennis drills
Authors: Reid M , Duffield R , Dawson B , Baker J , Crespo M
Published: August 2007

Objective:

To determine the physiological responses and stroke characteristics of common on-court tennis training drills.

Methods:

Six high-performance players performed 1×6 repetitions of four common on-court training drills on two separate occasions; once with 30:30 seconds work:rest, and once with 60:30 seconds work:rest. Heart rate (HR), blood lactate [La−], distance covered by the player (GPS) and rate of perceived exertion (RPE) were measured before the start of each drill and after the first and last repetition. Measures of shot count and accuracy and post-impact ball velocity per drill were also recorded.

Results:

Significant differences were observed between drills in measures of [La−] and RPE both during ([La−] 2.1–4.4 mmol/l; RPE 2.6–5.1) and after ([La−] 4.4–10.6 mmol/l; RPE 4.3–7.6) drills, yet individual HR responses (160–182 beats/minute) were similar. Increased work times (60v30 seconds) also produced consistently raised [La−] and RPE responses, yet players’ average movement velocities and forehand ball speed and accuracy remained consistent. Significant decreases in forehand ball speed and accuracy were observed during higher-intensity training drills, whereas significantly lower mean movement velocities underpinned performance of less intensive drills.

Conclusions:

The four drills produced physiological responses that reflect previously reported normal or maximal matchplay demands. These results point to the adaptations possible with adjustment of training drill type and load specific to matchplay demands or training phase.
Mortality, morbidity and occupational exposure to airway-irritating agents among men with a respiratory diagnosis in adolescence
Authors: Wiebert P , Svartengren M , Lindberg M , Hemmingsson T , Lundberg I , Nise G
Published: August 2007

Objectives:

To examine the influence of an airway diagnosis in adolescence on future health and occupation in Swedish men.

Methods:

Data were collected from the linkage of four Swedish national registers: the Military Service Conscription Register, the Population and Housing Censuses, the Inpatient Care Register and the National Cause of Death Register. A job-exposure matrix for airway-irritating substances was developed for application on the conscription cohort. The cohort included 49 321 Swedish men born 1949–51. Three groups—(1) healthy, (2) asthmatics (mild and severe asthma) and (3) subjects with allergic rhinitis without concurrent asthma—were identified at conscription and analysed for mortality, in-patient care and strategies for choice of occupation with emphasis on airway-irritating job exposure. Analyses were adjusted for smoking and childhood socioeconomic position.

Results:

The prevalence of total asthma was 1.8%, severe asthma 0.45% and allergic rhinitis 2.7%. Mortality for all causes was significantly higher in total asthma, hazard ratio (HR) 1.49 (95% CI 1.00 to 2.23), and lower in allergic rhinitis, HR 0.52 (95% CI 0.30 to 0.91). Asthma was a risk factor for inpatient care while allergic rhinitis was associated with less in-patient care (odds ratio (OR) for total asthma 1.16 (95% CI 1.00 to 1.34), severe asthma 1.38 (95% CI 1.04 to 1.85), allergic rhinitis 0.92 (95% CI 0.82 to 1.03)). Those with asthma tended to avoid jobs with a high probability for airway-irritating exposure (OR 0.88, 95% CI 0.71 to 1.09), but not to the same extent as subjects with allergic rhinitis (OR 0.58, 95% CI 0.47 to 0.70) (ORs from 1990).

Conclusion:

Subjects with asthma did not change their exposure situation to the same extent as subjects with allergic rhinitis. Further, asthmatics had an increased risk for morbidity and mortality compared to healthy subjects and subjects with allergic rhinitis.
The effectiveness of two occupational health intervention programmes in reducing sickness absence among employees at risk. Two randomised controlled trials
Authors: Taimela S , Malmivaara A , Justén S , Läärä E , Sintonen H , Tiekso J , Aro T
Published: August 2007

Objectives:

To evaluate the effectiveness of two occupational health intervention programmes, both compared with usual care.

Methods:

Based on a health survey, 1341 employees (88% males) in construction, service and maintenance work were classified into three groups: “low risk” (n = 386), “intermediate risk” (n = 537) and “high risk” (n = 418) of sickness absence. Two separate randomised trials were performed in the groups “high risk” and “intermediate risk”, respectively. Those high risk subjects that were allocated to the intervention group (n = 209) were invited to occupational health service for a consultation. The intervention included, if appropriate, a referral to specialist treatment. Among the intermediate risk employees those in the intervention group (n = 268) were invited to call a phone advice centre. In both trials the control group received usual occupational health care. The primary outcome was sickness absence during a 12-month follow-up (register data).

Results:

The high risk group, representing 31% of the cohort, accounted for 62% of sickness absence days. In the trial for the high risk group the mean sickness absence was 30 days in the usual care group and 19 days in the intervention group; the mean difference was 11 days (95% CI 1 to 20 days). In the trial for the intermediate risk group the mean sickness absence was 7 days in both arms (95% CI of the mean difference –2.3 to 2.4 days).

Conclusions:

The identification of high risk of work disability was successful. The occupational health intervention was effective in controlling work loss to a degree that is likely to be economically advantageous within the high risk group. The phone advice intervention for the intermediate risk group was not effective in controlling work loss primarily due to poor adherence.
Computer mouse use predicts acute pain but not prolonged or chronic pain in the neck and shoulder
Authors: Andersen J H , Harhoff M , Grimstrup S , Vilstrup I , Lassen C F , Brandt L P A , Kryger A I , Overgaard E , Hansen K D , Mikkelsen S
Published: August 2007

Background:

Computer use may have an adverse effect on musculoskeletal outcomes. This study assessed the risk of neck and shoulder pain associated with objectively recorded professional computer use.

Methods:

A computer programme was used to collect data on mouse and keyboard usage and weekly reports of neck and shoulder pain among 2146 technical assistants. Questionnaires were also completed at baseline and at 12 months. The three outcome measures were: (1) acute pain (measured as weekly pain); (2) prolonged pain (no or minor pain in the neck and shoulder region over four consecutive weeks followed by three consecutive weeks with a high pain score); and (3) chronic pain (reported pain or discomfort lasting more than 30 days and “quite a lot of trouble” during the past 12 months).

Results:

Risk for acute neck pain and shoulder pain increased linearly by 4% and 10%, respectively, for each quartile increase in weekly mouse usage time. Mouse and keyboard usage time did not predict the onset of prolonged or chronic pain in the neck or shoulder. Women had higher risks for neck and shoulder pain. Number of keystrokes and mouse clicks, length of the average activity period, and micro-pauses did not influence reports of acute or prolonged pain. A few psychosocial factors predicted the risk of prolonged pain.

Conclusions:

Most computer workers have no or minor neck and shoulder pain, few experience prolonged pain, and even fewer, chronic neck and shoulder pain. Moreover, there seems to be no relationship between computer use and prolonged and chronic neck and shoulder pain.
A DYNAMICAL MODEL WITH NEXT-NEAREST-NEIGHBOR INTERACTION IN RELATIVE VELOCITY
Authors: LI ZHIPENG , LIU YUNCAI , LIU FUQIANG
Published: August 2007

By introducing the velocity difference between the preceding car and the car before the preceding one into the optimal velocity model (OVM), we present an extended dynamical model which takes into account the next-nearest-neighbor interaction in relative velocity. The stability condition of this model is derived by considering a small perturbation around the uniform flow solution and the validity of our theoretical analysis is also confirmed by direct simulations. The analytic and simulation results indicate that traffic congestion is suppressed efficiently by incorporating the effect of new consideration. Moreover, the effect of the new consideration is investigated by numerical simulation. In particular, the jamming flow, the current-density relation, and the propagation speed of small disturbance are examined in detail by varying various values of the parameter.
OPINION FORMATION IN SZNAJD MODEL WITH MORE COMPLEX SOCIAL IMPACT
Authors: LIU ZI-RAN , YAN JIA-REN
Published: August 2007

Based on the Ising spin system and the Sznajd Model (SM), we introduce a new model to study the opinion evolving in SM on square lattices by numerical simulations. In the model, a panel of four neighboring sites are randomly selected at each Monte Carlo step (MCS), around the panel there are eight nearest neighbors. To be more realistic, two basic impacts are considered in the process of the eight individuals' decision-making, i.e., the information governed by the panel of four neighboring sites and the average opinion of the whole community. It is found that our model show many useful and interesting statistical results.
AN ACTIVE CONTROL FOR CHAOS SYNCHRONIZATION OF REAL AND COMPLEX VAN DER POL OSCILLATORS
Authors: FARGHALY AHMED A. M.
Published: August 2007

In a recent paper [Chaos, Solitons Fractals21, 915 (2004)], both real and complex Van der Pol oscillators were introduced and shown to exhibit chaotic limit cycles. In the present work these oscillators are synchronized by applying an active control technique. Based on Lyapunov function, the control input vectors are chosen and activated to achieve synchronization. The feasibility and effectiveness of the proposed technique are verified through numerical simulations.
PSEUDO RANDOM NUMBER GENERATION WITH THE AID OF ITERATED FUNCTION SYSTEMS ON ℝ2
Authors: BOUBOULIS P.
Published: August 2007

Two new pseudorandom number generators, based on iterated function systems (IFS), are introduced. An IFS is created based on an arbitrary seed and a set is constructed using the deterministic iteration algorithm (DIA). From this set pseudo random numbers have been constructed. The generators have big periods and pass all major statistical tests, indicating that they can be used in any application requiring random numbers, such as cryptography.
MODELING THE DYNAMICS OF DISASTER SPREADING FROM KEY NODES IN COMPLEX NETWORKS
Authors: WENG WEN GUO , NI SHUN JIANG , YUAN HONG YONG , FAN WEI CHENG
Published: August 2007

In this paper, we present the dynamics of disaster spreading from key nodes in complex networks. The key nodes have maximum and minimum out-degree nodes, which show important in spreading disaster. This paper considers directed Erdös–Rényi, scale-free and small-world networks. Using the model considering the common characteristics of infrastructure and lifeline networks, i.e., self-healing function and disaster spreading mechanism, we carry out simulations for the effects of the recovery time parameter and the time delay on the recovery rate and the number of damaged nodes. Simulation results show some typical disaster spreading characteristics, e.g., a non-equilibrium phase transition in the parameter space, disturbance from the maximum out-degree nodes resulting in more damaged effect, etc.
MODELING DRIVER BEHAVIOR ON URBAN STREETS
Authors: WANG RUILI , LIU MINGZHE , KEMP RAY , ZHOU MIN
Published: August 2007

Traffic flow on straight roads is the most common traffic phenomenon in urban road traffic networks. In this paper, a realistic cellular automaton (CA) model is proposed to investigate driver behavior on urban straight roads based on our field observations. Two types of driver behavior, free and car-following, are simulated. Free driving behavior is modeled by a novel five-stage speeding model (two acceleration stages, one steady stage and two deceleration stages). Car-following processes are simulated by using 1.5-s as the average headway (1.5-s rule), which is observed in local urban networks. Vehicular mechanical restrictions (acceleration and deceleration capabilities) are appropriately reflected by a five-stage speeding model, which has the dual-regimes of acceleration and deceleration. A fine grid (the length of each cell corresponds to 1 m) is used. Our simulation results demonstrate that the introduction of the dual-regimes of acceleration and deceleration, 1.5-s rule and fine grid matches actual driver behavior well on urban straight roads.
PROPERTY τ AND COUNTABLE BOREL EQUIVALENCE RELATIONS
Authors: THOMAS SIMON
Published: August 2007

We prove Borel superrigidity results for suitably chosen actions of groups of the form SL2(ℤ[1/p1, … , 1/pt]), where {p1, …, pt} is a finite nonempty set of primes, and present a number of applications to the theory of countable Borel equivalence relations. In particular, for each prime q, we prove that the orbit equivalence relations arising from the natural actions of SL2(ℤ[1/q]) on the projective lines ℚp∪ {∞}, p ≠ q, over the various p-adic fields are pairwise incomparable with respect to Borel reducibility.
EFFECTIVE CARDINALS OF BOLDFACE POINTCLASSES
Authors: ANDRETTA ALESSANDRO , HJORTH GREG , NEEMAN ITAY
Published: August 2007

Assuming AD + DC(ℝ), we characterize the self-dual boldface pointclasses which are strictly larger (in terms of cardinality) than the pointclasses contained in them: these are exactly the clopen sets, the collections of all sets of Wadge rank [Formula: see text], and those of Wadge rank [Formula: see text] when ξ is limit.
Intraportal GLP-1 infusion increases nonhepatic glucose utilization without changing pancreatic hormone levels
Authors: Johnson Kathryn M. S. , Edgerton Dale S. , Rodewald Tiffany , Scott Melanie , Farmer Ben , Neal Doss , Cherrington Alan D.
Published: August 2007

After a meal, glucagon-like peptide-1 (GLP-1) levels in the hepatic portal vein are elevated and are twice those in peripheral blood. The aim of this study was to determine whether any of GLP-1's acute metabolic effects are initiated within the hepatic portal vein. Experiments consisted of a 40-min basal period, followed by a 240-min experimental period, during which conscious 42-h-fasted dogs received glucose intraportally (4 mg·kg−1·min−1) and peripherally (as needed) to maintain arterial plasma glucose levels at ∼160 mg/dl. In addition, saline was given intraportally (CON; n = 8) or GLP-1 (1 pmol·kg−1·min−1) was given into the hepatic portal vein (POR; n = 11) or the hepatic artery (HAT; n = 8). Portal vein plasma GLP-1 levels were basal in CON, 20× basal in POR, and 10× basal in HAT, whereas levels in the periphery and liver were the same in HAT and CON. The glucose infusion rate required to maintain hyperglycemia was significantly greater in POR (8.5 ± 0.7 mg·kg−1·min−1, final 2 h) than in either CON or HAT (6.0 ± 0.5 or 6.7 ± 1.0 mg·kg−1·min−1, respectively). There were no differences among groups in either arterial plasma insulin (24 ± 2, 23 ± 3, and 23 ± 3 μU/ml for CON, POR, and HAT, respectively) or glucagon (23 ± 2, 30 ± 3, and 25 ± 2 pg/ml) levels during the experimental period. The increased need for glucose infusion reflected greater nonhepatic as opposed to liver glucose uptake. GLP-1 infusion increased glucose disposal independently of changes in pancreatic hormone secretion but only when the peptide was delivered intraportally.
Statistical Modeling and Analysis of Laser-Evoked Potentials of Electrocorticogram Recordings from Awake Humans
Authors: Chen Zhe , Ohara Shinji , Cao Jianting , Vialatte François , Lenz Fred A. , Cichocki Andrzej
Published: August 2007

This article is devoted to statistical modeling and analysis of electrocorticogram (ECoG) signals induced by painful cutaneous laser stimuli, which were recorded from implanted electrodes in awake humans. Specifically, with statistical tools of factor analysis and independent component analysis, the pain-induced laser-evoked potentials (LEPs) were extracted and investigated under different controlled conditions. With the help of wavelet analysis, quantitative and qualitative analyses were conducted regarding the LEPs' attributes of power, amplitude, and latency, in both averaging and single-trial experiments. Statistical hypothesis tests were also applied in various experimental setups. Experimental results reported herein also confirm previous findings in the neurophysiology literature. In addition, single-trial analysis has also revealed many new observations that might be interesting to the neuroscientists or clinical neurophysiologists. These promising results show convincing validation that advanced signal processing and statistical analysis may open new avenues for future studies of such ECoG or other relevant biomedical recordings.
Connecting Neurons to a Mobile Robot: An In Vitro Bidirectional Neural Interface
Authors: Novellino A. , D'Angelo P. , Cozzi L. , Chiappalone M. , Sanguineti V. , Martinoia S.
Published: August 2007

One of the key properties of intelligent behaviors is the capability to learn and adapt to changing environmental conditions. These features are the result of the continuous and intense interaction of the brain with the external world, mediated by the body. For this reason x201C;embodiment” represents an innovative and very suitable experimental paradigm when studying the neural processes underlying learning new behaviors and adapting to unpredicted situations. To this purpose, we developed a novel bidirectional neural interface. We interconnected in vitro neurons, extracted from rat embryos and plated on a microelectrode array (MEA), to external devices, thus allowing real-time closed-loop interaction. The novelty of this experimental approach entails the necessity to explore different computational schemes and experimental hypotheses. In this paper, we present an open, scalable architecture, which allows fast prototyping of different modules and where coding and decoding schemes and different experimental configurations can be tested. This hybrid system can be used for studying the computational properties and information coding in biological neuronal networks with far-reaching implications for the future development of advanced neuroprostheses.
A Novel Constrained Topographic Independent Component Analysis for Separation of Epileptic Seizure Signals
Authors: Jing Min , Sanei Saeid
Published: August 2007

Blind separation of the electroencephalogram signals (EEGs) using topographic independent component analysis (TICA) is an effective tool to group the geometrically nearby source signals. The TICA algorithm further improves the results if the desired signal sources have particular properties which can be exploited in the separation process as constraints. Here, the spatial-frequency information of the seizure signals is used to design a constrained TICA for the separation of epileptic seizure signal sources from the multichannel EEGs. The performance is compared with those from the TICA and other conventional ICA algorithms. The superiority of the new constrained TICA has been validated in terms of signal-to-interference ratio and correlation measurement.
RAR/RXR and PPAR/RXR Signaling in Spinal Cord Injury
Authors: van Neerven Sabien , Mey Jörg
Published: August 2007

The retinoid acid receptors (RAR) and peroxisome proliferator-activated receptors (PPAR) have been implicated in the regulation of inflammatory reactions. Both receptor families contain ligand-activated transcription factors which form heterodimers with retinoid X receptors (RXR). We review data that imply RAR/RXR and PPAR/RXR pathways in physiological reactions after spinal cord injury. Experiments show how RAR signaling may improve axonal regeneration and modulate reactions of glia cells. While anti-inflammatory properties of PPAR are well documented in the periphery, their possible roles in the central nervous system have only recently become evident. Due to its anti-inflammatory function this transcription factor family promises to be a useful target after spinal cord or brain lesions.
Natural Circulation in the ATUCHA-I PHWR Nuclear Power Plant
Authors: Mazzantini O. , Ferreri J. C. , D'Auria F. , Camusso C. P.
Published: August 2007

A systematic study of natural circulation (NC) in a postulated, varying primary mass inventory scenario at residual power fractions has been performed for a nuclear power plant operating in Argentina. It is a pressurized heavy water reactor, cooled and moderated by heavy water. The analysis seems particularly relevant at present, because a second nuclear power plant (NPP), of similar design and nearly 745 MWe, is now under finalization. NRC-RELAP5/MOD3.3 was the code used to perform the simulations. Results obtained are presented in the form of natural circulation flow maps. The trends obtained fit in the expected limits for integral test facilities representative of PWRs. In addition, the validity of a simplified analysis to scale single and two-phase core flow has been verified. A set of constants has been obtained, which permits predicting NC core mass flow rate (CMFR) for this NPP. Results are partially validated, for single-phase NC flow, using a documented plant transient, showing reasonable agreement. Also, the effect of pressurizer size on the predicted evolution curve in the NC flow map (NCFM) is discussed.
The Importance of Cognitive Phenotypes in Experimental Modeling of Animal Anxiety and Depression
Authors: Kalueff Allan V. , Murphy Dennis L.
Published: August 2007

Cognitive dysfunctions are commonly seen in many stress-related disorders, including anxiety and depression—the world's most common neuropsychiatric illnesses. Various genetic, pharmacological, and behavioral animal models have long been used to establish animal anxiety-like and depression-like phenotypes, as well as to assess their memory, learning, and other cognitive functions. Mounting clinical and animal evidences strongly supports the notion that disturbed cognitions represent an important pathogenetic factor in anxiety and depression, and may also play a role inintegratingthe two disorders within a common stress-precipitated developmental pathway. This paper evaluates why and how the assessment of cognitive and emotional domains may improve our understanding of animal behaviors via different high-throughput tests and enable a better translation of animal phenotypes into human brain disorders.
The Polyol Pathway as a Mechanism for Diabetic Retinopathy: Attractive, Elusive, and Resilient
Authors: Lorenzi Mara
Published: August 2007

The polyol pathway is a two‐step metabolic pathway in which glucose is reduced to sorbitol, which is then converted to fructose. It is one of the most attractive candidate mechanisms to explain, at least in part, the cellular toxicity of diabetic hyperglycemia because (i) it becomes active when intracellular glucose concentrations are elevated, (ii) the two enzymes are present in human tissues and organs that are sites of diabetic complications, and (iii) the products of the pathway and the altered balance of cofactors generate the types of cellular stress that occur at the sites of diabetic complications. Inhibition (or ablation) of aldose reductase, the first and rate‐limiting enzyme in the pathway, reproducibly prevents diabetic retinopathy in diabetic rodent models, but the results of a major clinical trial have been disappointing. Since then, it has become evident that truly informative indicators of polyol pathway activity and/or inhibition are elusive, but are likely to be other than sorbitol levels if meant to predict accurately tissue consequences. The spectrum of abnormalities known to occur in human diabetic retinopathy has enlarged to include glial and neuronal abnormalities, which in experimental animals are mediated by the polyol pathway. The endothelial cells of human retinal vessels have been noted to have aldose reductase. Specific polymorphisms in the promoter region of the aldose reductase gene have been found associated with susceptibility or progression of diabetic retinopathy. This new knowledge has rekindled interest in a possible role of the polyol pathway in diabetic retinopathy and in methodological investigation that may prepare new clinical trials. Only new drugs that inhibit aldose reductase with higher efficacy and safety than older drugs will make possible to learn if the resilience of the polyol pathway means that it has a role in human diabetic retinopathy that should not have gone undiscovered.
Canonical Source Reconstruction for MEG
Authors: Mattout Jérémie , Henson Richard N. , Friston Karl J.
Published: August 2007

We describe a simple and efficient solution to the problem of reconstructing electromagnetic sources into a canonical or standard anatomical space. Its simplicity rests upon incorporating subject-specific anatomy into the forward model in a way that eschews the need for cortical surface extraction. The forward model starts with a canonical cortical mesh, defined in a standard stereotactic space. The mesh is warped, in a nonlinear fashion, to match the subject's anatomy. This warping is the inverse of the transformation derived from spatial normalization of the subject's structural MRI image, using fully automated procedures that have been established for other imaging modalities. Electromagnetic lead fields are computed using the warped mesh, in conjunction with a spherical head model (which does not rely on individual anatomy). The ensuing forward model is inverted using an empirical Bayesian scheme that we have described previously in several publications. Critically, because anatomical information enters the forward model, there is no need to spatially normalize the reconstructed source activity. In other words, each source, comprising the mesh, has a predetermined and unique anatomical attribution within standard stereotactic space. This enables the pooling of data from multiple subjects and the reporting of results in stereotactic coordinates. Furthermore, it allows the graceful fusion of fMRI and MEG data within the same anatomical framework.
Successive Bifurcation Conditions of a Lorenz-Type Equation for the Fluid Convection Due to the Transient Thermal Field
Authors: He Xiaoling
Published: August 2007

This paper investigates the convection flow between the two parallel plates in a fluid cell subject to the transient thermal field. We use the modal approximations similar to that of the original Lorenz model to obtain a generalized Lorenz-type model for the flow induced by the transient thermal field at the bottom plate. This study examines the convection flow bifurcation conditions in relation to the transient temperature variations and the flow properties. We formulated successive bifurcation conditions and illustrated the various flow behaviors and their steady-state attractors affected by the thermal field functions and fluid properties.
Dunkl Translation and Uncentered Maximal Operator on the Real Line
Authors: Abdelkefi Chokri , Sifi Mohamed
Published: August 2007

We establish estimates of the Dunkl translation of the characteristic functionχ[−ɛ,ɛ],ɛ>0, and we prove that the uncentered maximal operator associated with the Dunkl operator is of weak type(1,1). As a consequence, we obtain theLp-boundedness of this operator for1<p≤+∞.
A Family of Non-Gaussian Martingales with Gaussian Marginals
Authors: Hamza Kais , Klebaner Fima C.
Published: August 2007

We construct a family of martingales with Gaussian marginal distributions. We give a weak construction as Markov, inhomogeneous in time processes, and compute their infinitesimal generators. We give the predictable quadratic variation and show that the paths are not continuous. The construction uses distributions Gσ having a log-convolution semigroup property. Further, we categorize these
processes as belonging to one of two classes, one of which is made up of piecewise deterministic pure jump processes. This class includes the case where Gσ is an inverse log-Poisson distribution. The processes in the second
class include the case where Gσ is an inverse log-gamma distribution. The richness of the family has the potential to allow for the imposition of specifications other than the marginal distributions.
Fully Online Multicommand Brain-Computer Interface with Visual Neurofeedback Using SSVEP Paradigm
Authors: Martinez Pablo , Bakardjian Hovagim , Cichocki Andrzej
Published: August 2007

We propose a new multistage procedure for a real-time brain-machine/computer interface (BCI). The developed system allows a BCI user to navigate a small car (or any other object) on the computer screen in real time, in any of the four directions, and to stop it if necessary. Extensive experiments with five young healthy subjects confirmed the high performance of the proposed online BCI system. The modular structure, high speed, and the optimal frequency band characteristics of the BCI platform are features which allow an extension to a substantially higher number of commands in the near future.