bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Environment of 16S rRNA Methylase Gene
rmtD
Authors: Doi Yohei , Adams-Haduch Jennifer M. , Paterson David L.
Published: April 2008

The genetic environment of the 16S rRNA methylase gene
rmtD
was investigated.
rmtD
was flanked by a novel IS
CR
motif located downstream of class I integron In
163
in the original
Pseudomonas aeruginosa
strain.
rmtD
found in
Klebsiella pneumoniae
appeared to have been mobilized from
P. aeruginosa
by an IS
26
-mediated event.
Increasing Incidence of Linezolid-Intermediate or -Resistant, Vancomycin-Resistant
Enterococcus faecium
Strains Parallels Increasing Linezolid Consumption
Authors: Scheetz Marc H. , Knechtel Stephanie A. , Malczynski Michael , Postelnick Michael J. , Qi Chao
Published: April 2008

Clinical enterococcal resistance to linezolid is defined by the presence of the G2576T mutation. We evaluated the incidence of genetically proven linezolid resistance among vancomycin-resistant
Enterococcus faecium
strains and linezolid consumption for a possible association. A relationship was found (
r
2
= 0.73,
P
= 0.03) and predicts increasing resistance with current trends of linezolid use.
Mechanism of Inhibition of Human Immunodeficiency Virus Type 1 Reverse Transcriptase by a Stavudine Analogue, 4′-Ethynyl Stavudine Triphosphate
Authors: Yang Guangwei , Wang Jimin , Cheng Yao , Dutschman Ginger E. , Tanaka Hiromichi , Baba Masanori , Cheng Yung-Chi
Published: April 2008

2′,3′-Didehydro-3′-deoxy-4′-ethynylthymidine (4′-Ed4T), a recently discovered nucleoside reverse transcriptase (RT) inhibitor, exhibits 5- to 10-fold-higher activity against human immunodeficiency virus type 1 (HIV-1) and less cytotoxicity than does its parental compound d4T (stavudine). Using steady-state kinetic approaches, we have previously shown that (i) 4′-ethynyl-d4T triphosphate (4′-Ed4TTP) inhibits HIV-1 RT more efficiently than d4TTP does and (ii) its inhibition efficiency toward the RT M184V mutant is threefold less than that toward wild-type (wt) RT. In this study we used pre-steady-state kinetic approaches in an attempt to understand its mechanism of inhibition. With wt and the M184V mutant RTs, 4′-Ed4TTP has three- to fivefold-lower

K
d

(dissociation constant) values than d4TTP, while d4TTP has up to eightfold-higher

K
d

values than dTTP. Inhibition is more effective in DNA replication with RNA template than with DNA template. In general, the M184V mutant exhibits poorer binding for all three nucleoside triphosphates than does wt RT. The structural basis for the lower binding affinity of d4TTP than of dTTP could be the lack of hydrogen bonds from the missing 3′-hydroxyl group in d4TTP to the backbone amide of Y115 and also to the side chain of Q151. The structural basis for the higher binding affinity of 4′-Ed4TTP than of d4TTP could be the additional binding of the 4′-ethynyl group in a preformed hydrophobic pocket by A114, Y115, M184, F160, and part of D185.
In Vitro Activities of Linezolid against Clinical Isolates of
Mycobacterium tuberculosis
Complex Isolated in Taiwan over 10 Years
Authors: Huang Tsi-Shu , Liu Yung-Ching , Sy Cheng-Len , Chen Yao-Shen , Tu Hui-Zin , Chen Bao-Chen
Published: April 2008

Significant increases in the MIC
90
s of linezolid in multidrug-resistant
Mycobacterium tuberculosis
isolates were seen between the baseline period of 2001 to 2003 (0.5 μg/ml) and 2004 (2 μg/ml). The MICs were 4 μg/ml in three strains. Both fluoroquinolones (except levofloxacin) and kanamycin were found to have statistically significant degrees of concordance with linezolid.
RNAIII-Inhibiting Peptide Enhances Healing of Wounds Infected with Methicillin-Resistant
Staphylococcus aureus
Authors: Simonetti Oriana , Cirioni Oscar , Ghiselli Roberto , Goteri Gaia , Scalise Alessandro , Orlando Fiorenza , Silvestri Carmela , Riva Alessandra , Saba Vittorio , Madanahally Kiran D. , Offidani Annamaria , Balaban Naomi , Scalise Giorgio , Giacometti Andrea
Published: April 2008

Quorum sensing is a mechanism through which a bacterial population receives input from neighboring cells and elicits an appropriate response to enable survival within the host. Inhibiting quorum sensing by RNAIII-inhibiting peptide (RIP) has been demonstrated as a very effective mode of prevention and therapy for device-associated staphylococcal infections and was tested here for healing of wounds that are otherwise resistant to conventional antibiotics. Wounds, established through the panniculus carnosus of BALB/c mice, were inoculated with 5 × 10
7
CFU of methicillin-resistant
Staphylococcus aureus
. Mice were treated with Allevyn, RIP-soaked Allevyn (containing 20 μg RIP), daily intraperitoneal teicoplanin (7 mg/kg of body weight), Allevyn and teicoplanin, and RIP-soaked Allevyn and daily intraperitoneal teicoplanin. The main outcome measures were quantitative bacterial culture and histological examination with assessment of microvessel density and of vascular endothelial growth factor (VEGF) expression in tissue sections. Treatment with RIP-soaked Allevyn together with teicoplanin injection greatly reduced the bacterial load to 13 CFU/g (control untreated animals had 10
8
CFU/g bacteria). All other treatments were also significantly effective but only reduced the bacterial load to about 10
3
CFU/ml. Histological examination indicated that only treatment with RIP-soaked Allevyn with teicoplanin injection restored epithelial, granulation, and collagen scores, as well as microvessel density and VEGF expression, to the levels found with uninfected mice. In conclusion, we observed that RIP may be useful for the management of infected wounds and that it could represent an exciting and future alternative to the conventional antibiotics, at present considered the gold-standard treatments for methicillin-resistant
S. aureus
infections.
Lack of an Effect of Human Immunodeficiency Virus Coinfection on the Pharmacokinetics of Entecavir in Hepatitis B Virus-Infected Patients
Authors: Zhu Min , Bifano Marc , Xu Xu , Wang Yonghua , LaCreta Frank , Grasela Dennis , Pfister Marc
Published: April 2008

Entecavir is a guanosine nucleoside analogue approved for the treatment of chronic hepatitis B virus (HBV) infection. The impact of human immunodeficiency virus (HIV) coinfection on the pharmacokinetics (PK) of entecavir was examined by nonlinear mixed-effects modeling. Plasma concentration data from HIV- and HBV-coinfected patients were analyzed in conjunction with data from HBV-monoinfected patients, and HIV coinfection was tested as a covariate on oral clearance (CL/
F
). The estimated population averages of intercompartmental clearance and the volumes of distribution in the central and peripheral compartments obtained with a 1-mg dose were 34.2 liters/h (interindividual variability, 30.2%), 115 liters (interindividual variability, 39.2%), and 1,830 liters (interindividual variability, 74%), respectively. CL/
F
was found to be a function of creatinine clearance, but HIV confection did not show any effect on CL/
F
. The geometric mean (GM) of individual Bayesian estimates of the steady-state area under the concentration-time curve following 1-mg daily doses were 39.3 and 38.8 ng·h/ml in HIV- and HBV-coinfected and HBV-monoinfected patients, respectively. The adjusted GM ratio (1.01; 90% confidence interval, 0.91 to 1.12) was within the bioequivalence criteria boundary (0.80 to 1.25). In conclusion, the proposed model adequately described the entecavir PK in HBV- and HIV-coinfected patients and HBV-monoinfected patients, and the entecavir exposures were comparable in the two patient populations.
Effects of Mutagenic and Chain-Terminating Nucleotide Analogs on Enzymes Isolated from Hepatitis C Virus Strains of Various Genotypes
Authors: Heck Julie A. , Lam Angela M. I. , Narayanan Nirupama , Frick David N.
Published: April 2008

The development of effective therapies for hepatitis C virus (HCV) must take into account genetic variation among HCV strains. Response rates to interferon-based treatments, including the current preferred treatment of pegylated alpha interferon administered with ribavirin, are genotype specific. Of the numerous HCV inhibitors currently in development as antiviral drugs, nucleoside analogs that target the conserved NS5B active site seem to be quite effective against diverse HCV strains. To test this hypothesis, we examined the effects of a panel of nucleotide analogs, including ribavirin triphosphate (RTP) and several chain-terminating nucleoside triphosphates, on the activities of purified HCV NS5B polymerases derived from genotype 1a, 1b, and 2a strains. Unlike the genotype-specific effects on NS5B activity reported previously for nonnucleoside inhibitors (F. Pauwels, W. Mostmans, L. M. Quirynen, L. van der Helm, C. W. Boutton, A. S. Rueff, E. Cleiren, P. Raboisson, D. Surleraux, O. Nyanguile, and K. A. Simmen, J. Virol.81:6909-6919, 2007), only minor differences in inhibition were observed among the various genotypes; thus, nucleoside analogs that are current drug candidates may be more promising for treatment of a broader variety of HCV strains. We also examined the effects of RTP on the HCV NS3 helicase/ATPase. As with the polymerase, only minor differences were observed among 1a-, 1b-, and 2a-derived enzymes. RTP did not inhibit the rate of NS3 helicase-catalyzed DNA unwinding but served instead as a substrate to fuel unwinding. NS3 added to RNA synthesis reactions relieved inhibition of the polymerase by RTP, presumably due to RTP hydrolysis. These results suggest that NS3 can limit the incorporation of ribavirin into viral RNA, thus reducing its inhibitory or mutagenic effects.
Potency of SMP-601, a Novel Carbapenem, in Hematogenous Murine Bronchopneumonia Caused by Methicillin-Resistant and Vancomycin-Intermediate
Staphylococcus aureus
Authors: Kihara Rie , Yanagihara Katsunori , Morinaga Yoshitomo , Araki Nobuko , Nakamura Shigeki , Seki Masafumi , Izumikawa Koichi , Kakeya Hiroshi , Yamamoto Yoshihiro , Tsukamoto Kazuhiro , Kamihira Shimeru , Kohno Shigeru
Published: April 2008

We compared the potency of SMP-601, a novel carbapenem, with that of vancomycin in a murine model of hematogenous bronchopneumonia infection caused by methicillin-resistant
Staphylococcus aureus
(MRSA) and vancomycin-intermediate
S. aureus
(VISA). The MICs of SMP-601 and vancomycin against MRSA were 2 and 1 μg/ml, respectively, while those against VISA were 2 and 8 μg/ml, respectively. Treatment with SMP-601 resulted in a significant decrease in the number of viable bacteria in the MRSA infection model (control, 100 mg/kg vancomycin, and 100 mg/kg SMP-601, 8.42 ± 0.50, 5.29 ± 0.71, and 5.50 ± 0.58 log CFU/lung, respectively,) and in the VISA infection model (control, 100 mg/kg vancomycin, and 100 mg/kg SMP-601, 9.64 ± 0.63, 8.72 ± 0.45, 7.42 ± 0.14 log CFU/lung) (mean ± standard error of the mean). The survival rate in the VISA infection model treated with SMP-601 (70%) was significantly higher than those in the other two groups (20% for vancomycin and 0% for control;
P
< 0.05). Histopathological examination revealed that inflammatory changes in the SMP-601-treated group were less marked than in the other two groups. The results of pharmacokinetic-pharmacodynamic analysis supported the results of the bacteriological, histopathological and survival studies. Our results demonstrate the potency of SMP-601 against MRSA and VISA in murine hematogenous pulmonary infection.
Nasal Immunization with
Lactococcus lactis
Expressing the Pneumococcal Protective Protein A Induces Protective Immunity in Mice
Authors: Medina Marcela , Villena Julio , Vintiñi Elisa , Hebert Elvira María , Raya Raúl , Alvarez Susana
Published: April 2008

Nisin-controlled gene expression was used to develop a recombinant strain of
Lactococcus lactis
that is able to express the pneumococcal protective protein A (PppA) on its surface. Immunodetection assays confirmed that after the induction with nisin, the PppA antigen was predictably and efficiently displayed on the cell surface of the recombinant strain, which was termed
L. lactis
PppA. The production of mucosal and systemically specific antibodies in adult and young mice was evaluated after mice were nasally immunized with
L. lactis
PppA. Immunoglobulin M (IgM), IgG, and IgA anti-PppA antibodies were detected in the serum and bronchoalveolar lavage fluid of adult and young mice, which showed that PppA expressed in
L. lactis
was able to induce a strong mucosal and systemic immune response. Challenge survival experiments demonstrated that immunization with
L. lactis
PppA was able to increase resistance to systemic and respiratory infection with different pneumococcal serotypes, and passive immunization assays of naïve young mice demonstrated a direct correlation between anti-PppA antibodies and protection. The results presented in this study demonstrate three major characteristics of the effectiveness of nasal immunization with PppA expressed as a protein anchored to the cell wall of
L. lactis
: it elicited cross-protective immunity against different pneumococcal serotypes, it afforded protection against both systemic and respiratory challenges, and it induced protective immunity in mice of different ages.
Extracellular Signal-Regulated Kinase Activation by
Neisseria gonorrhoeae
Downregulates Epithelial Cell Proapoptotic Proteins Bad and Bim
Authors: Howie Heather L. , Shiflett Shelly L. , So Magdalene
Published: April 2008

Neisseria gonorrhoeae
expressing type IV pili (Tfp) activates extracellular signal-regulated kinase (ERK) and induces a cytoprotective state in the epithelial cell in a manner that is enhanced by
pilT
. As the ERK signaling pathway is well-known for its role in cytoprotection and cell survival, we tested the hypothesis that ERK is involved in producing this cytoprotective effect. Inhibiting ERK activation prior to infection attenuated the ability of these bacteria to induce cytoprotection. Activated ERK specifically targeted two proapoptotic Bcl-2 homology domain 3 (BH3)-only proteins, Bim and Bad, for downregulation at the protein level. Bim downregulation occurred through the proteasome. ERK, in addition, inactivated Bad by triggering its phosphorylation at Ser112. Finally, reducing the level of either Bad or Bim alone by small interfering RNA was sufficient to protect uninfected cells from staurosporine-induced apoptosis. We conclude that Tfp-induced cytoprotection is due in part to ERK-dependent modification and/or downregulation of proapoptotic proteins Bad and Bim.
Highly Conserved Surface Proteins of Oral Spirochetes as Adhesins and Potent Inducers of Proinflammatory and Osteoclastogenic Factors
Authors: Jun Hye-Kyoung , Kang Young-Mi , Lee Hae-Ri , Lee Sung-Hoon , Choi Bong-Kyu
Published: April 2008

Oral spirochetes include enormously heterogeneousTreponemaspecies, and some have been implicated in the etiology of periodontitis. In this study, we characterized highly conserved surface proteins in four representative oral spirochetes (Treponema denticola, T. lecithinolyticum, T. maltophilum, andT. socranskiisubsp.socranskii) that are homologs ofT. pallidumTp92, with opsonophagocytic potential and protective capacity against syphilis. Tp92 homologs of oral spirochetes had predicted signal peptides (20 to 31 amino acids) and molecular masses of 88 to 92 kDa for mature proteins. They showed amino acid sequence identities of 37.9 to 49.3% and similarities of 54.5 to 66.9% to Tp92. The sequence identities and similarities of Tp92 homologs of oral treponemes to one another were 41.6 to 71.6% and 59.9 to 85.6%, respectively. Thetp92gene homologs were successfully expressed inEscherichia coli, and the recombinant proteins were capable of binding to KB cells, an epithelial cell line, and inhibited the binding of the whole bacteria to the cells. Antiserum (the immunoglobulin G fraction) raised against a recombinant form of theT. denticolaTp92 homolog cross-reacted with homologs from three other species of treponemes. The Tp92 homologs stimulated various factors involved in inflammation and osteoclastogenesis, like interleukin-1β (IL-1β), tumor necrosis factor alpha, IL-6, prostaglandin E2, and matrix metalloproteinase 9, in host cells like monocytes and fibroblasts. Our results demonstrate that Tp92 homologs of oral spirochetes are highly conserved and may play an important role in cell attachment, inflammation, and tissue destruction. The coexistence of variousTreponemaspecies in a single periodontal pocket and, therefore, the accumulation of multiple Tp92 homologs may amplify the pathological effect in periodontitis.
Borrelia burgdorferi
Surface-Localized Proteins Expressed during Persistent Murine Infection Are Conserved among Diverse
Borrelia
spp
Authors: Hughes Jessica L. , Nolder Christi L. , Nowalk Andrew J. , Clifton Dawn R. , Howison Rebekah R. , Schmit Virginia L. , Gilmore Robert D. , Carroll James A.
Published: April 2008

Borrelia burgdorferi
, the causative agent of Lyme disease in the United States, regulates numerous genes encoding lipoproteins on linear plasmid 54 in response to environmental cues. We analyzed a subset of these genes/proteins that were historically categorized as paralogous gene family 54 (BBA64, BBA65, BBA66, BBA68, BBA69, BBA70, BBA71, and BBA73) and found that the expression of several genes was influenced by the σ
N
-σ
S
regulatory cascade at the level of transcription and protein synthesis. Moreover, we established in this and a previous study that BBA65, BBA66, BBA69, BBA71, and BBA73 are temporally expressed during persistent infection of immunocompetent mice, as determined by quantitative real time-PCR of ear tissue, by enzyme-linked immunosorbent assay, and by immunoblotting. Correspondingly, BBA65, BBA66, BBA71, and BBA73 proteins were detectable in infectious
B. burgdorferi
B31 isolates but undetectable in noninfectious isolates. BBA65, BBA66, BBA71, and BBA73 proteins were also found to partition into the Triton X-114 detergent phase and were sensitive to protease treatment of intact cells, indicating that they are membrane associated and surface localized. Lastly, Southern blotting and PCR with specific gene primer/probes for BBA64, BBA65, BBA66, BBA71, and BBA73 suggest that many of these genes are conserved among the
B. burgdorferi
sensu lato isolates and the relapsing-fever
Borrelia
species. Together, the data presented suggest that these genes may play a part in
Borrelia
infection and/or pathogenicity that could extend beyond the sensu lato group.
In LipL32, the Major Leptospiral Lipoprotein, the C Terminus Is the Primary Immunogenic Domain and Mediates Interaction with Collagen IV and Plasma Fibronectin
Authors: Hauk Pricila , Macedo Felipe , Romero Eliete Caló , Vasconcellos Sílvio Arruda , de Morais Zenaide Maria , Barbosa Angela Silva , Ho Paulo Lee
Published: April 2008

LipL32 is the major leptospiral outer membrane lipoprotein expressed during infection and is the immunodominant antigen recognized during the humoral immune response to leptospirosis in humans. In this study, we investigated novel aspects of LipL32. In order to define the immunodominant domains(s) of the molecule, subfragments corresponding to the N-terminal, intermediate, and C-terminal portions of the LipL32 gene were cloned and the proteins were expressed and purified by metal affinity chromatography. Our immunoblot results indicate that the C-terminal and intermediate domains of LipL32 are recognized by sera of patients with laboratory-confirmed leptospirosis. An immunoglobulin M response was detected exclusively against the LipL32 C-terminal fragment in both the acute and convalescent phases of illness. We also evaluated the capacity of LipL32 to interact with extracellular matrix (ECM) components. Dose-dependent, specific binding of LipL32 to collagen type IV and plasma fibronectin was observed, and the binding capacity could be attributed to the C-terminal portion of this molecule. Both heparin and gelatin could inhibit LipL32 binding to fibronectin in a concentration-dependent manner, indicating that the 30-kDa heparin-binding and 45-kDa gelatin-binding domains of fibronectin are involved in this interaction. Taken together, our results provide evidence that the LipL32 C terminus is recognized early in the course of infection and is the domain responsible for mediating interaction with ECM proteins.
Heart rate and exercise intensity during training: observations from the DREW Study
Authors: Mikus C R , Earnest C P , Blair S N , Church T S
Published: April 2008

Objective:

Cardiovascular drift (CVdrift) is characterised by a continuous, gradual increase in heart rate (HR) after ∼10 min of moderate-intensity aerobic exercise, despite maintenance of a constant work rate. This has important implications for trials that employ HR to monitor exercise intensity, as reducing work rate in order to keep HR constant could result in participants exercising below the intended intensity. Utilising the Dose Response to Exercise in Women (DREW) database, we sought to determine if increases in HR during exercise (CVdrift) resulted in clinically significant reductions in exercise work rate in order to keep HR within a target range.

Design:

Randomised, prospective study.

Setting:

DREW clinical exercise trail, The Cooper Institute, Dallas, Texas.

Participants:

Overweight (body mass index 25–43 kg/m2), previously sedentary postmenopausal women (n  =  326).

Intervention:

Treadmill and cycling exercise (30–90 min, three to five times per week) at a HR corresponding to 50% of peak oxygen uptake (Vo2peak).

Main outcome measure:

Changes in exercise intensity (metabolic equivalents (METS)) during exercise in response to CVdrift.

Results:

We observed small increases in HR (1–4 beats per minute, p<0.001) combined with small increases in intensity (0.01–0.03 METS, p<0.03) during the combined 12 963 exercise training sessions. Further, we identified only 101 (0.78%) sessions in which intensity was reduced during the course of the exercise session, potentially in response to CVdrift.

Conclusions:

We conclude that CVdrift did not contribute to significant reductions in exercise intensity in the DREW study.
Effect of proprioception training on knee joint position sense in female team handball players
Authors: Pánics G , Tállay A , Pavlik A , Berkes I
Published: April 2008

Background:

A number of studies have shown that proprioception training can reduce the risk of injuries in pivoting sports, but the mechanism is not clearly understood.

Aim:

To determine the contributing effects of propioception on knee joint position sense among team handball players.

Study design:

Prospective cohort study.

Methods:

Two professional female handball teams were followed prospectively for the 2005–6 season. 20 players in the intervention team followed a prescribed proprioceptive training programme while 19 players in the control team did not have a specific propioceptive training programme. The coaches recorded all exposures of the individual players. The location and nature of injuries were recorded. Joint position sense (JPS) was measured by a goniometer on both knees in three angle intervals, testing each angle five times. Assessments were performed before and after the season by the same examiner for both teams. In the intervention team a third assessment was also performed during the season. Complete data were obtained for 15 subjects in the intervention team and 16 in the control team. Absolute error score, error of variation score and SEM were calculated and the results of the intervention and control teams were compared.

Results:

The proprioception sensory function of the players in the intervention team was significantly improved between the assessments made at the start and the end of the season (mean (SD) absolute error 9.78–8.21° (7.19–6.08°) vs 3.61–4.04°(3.71–3.20°), p<0.05). No improvement was seen in the sensory function in the control team between the start and the end of the season (mean (SD) absolute error 6.31–6.22°(6.12–3.59°) vs 6.13–6.69°(7.46–6.49°), p>0.05).

Conclusion:

This is the first study to show that proprioception training improves the joint position sense in elite female handball players. This may explain the effect of neuromuscular training in reducing the injury rate.
Consequences of dramatic reductions in state tobacco control funds: Florida, 1998–2000
Authors: Niederdeppe J , Farrelly M C , Hersey J C , Davis K C
Published: April 2008

Objective:

This study assessed whether dramatic funding reductions to the Florida Tobacco Control Program (FTCP) influenced trends in recall of the Florida “truth” anti-smoking media campaign, anti-industry attitudes and non-smoking intentions among Florida teens.

Methods:

We used an interrupted time series technique to test for differences in the rates of change in Florida “truth” recall, anti-industry beliefs and non-smoking intentions before and after the FTCP budget cuts using the Florida Anti-tobacco Media Evaluation (FAME) survey, a repeated cross-sectional telephone survey of Florida teens.

Results:

Recall of the Florida “truth” anti-smoking campaign, anti-industry attitudes, and non-smoking intentions increased dramatically between April 1998 and May 1999. Florida “truth” recall declined after FTCP budget cuts in June 1999. Anti-industry beliefs and non-smoking intentions plateaued or began to decline after the budget cuts. The launch of the national “truth” campaign in February 2000 may have offset otherwise deleterious effects of the budget cuts on anti-industry beliefs, but not smoking intentions.

Conclusion:

Reductions in tobacco control funding have immediate effects on programme exposure and cognitive precursors to smoking initiation. There is a critical need to maintain and enhance funding for state tobacco control programmes to continue nationwide progress in preventing youth from initiating cigarette smoking.
Nitrogen Fixation and Phosphorus Turnover in a Hypertrophic Prairie Lake
Authors: Brownlee B. G. , Murphy T. P.
Published: April 2008

Nitrogen fixation by Aphanizomenon flos-aquae in a prairie lake in southwestern Manitoba was dependent on the light intensity and in situ oxygen concentrations. The mean molar ratio of acetylene reduction to nitrogen reduction was 5.8:1. High external ammonium concentrations did not appear to inhibit nitrogen fixation over the short term. Nitrogen fixation was not directly initiated by the bloom collapse. We propose that the coupled sequence of ammonia volatilization and nitrogen fixation was triggered by the bloom collapse and that the bloom collapse was caused by coprecipitation of orthophosphate with carbonates. 32PO4 turnover was most rapid during periods when the lake was opalescent, presumably due to carbonate precipitaton.
Estimating Population Size from Relative Abundance Data Measured with Error
Authors: Collie Jeremy S. , Sissenwine Michael P.
Published: April 2008

A modified DeLury method to estimate fish population size from relative abundance data was developed. The method may be applied either with or without knowledge of the age composition of catch. In addition to estimating catchability coefficients, the technique accounts for error in the measurement of relative abundance. A general-purpose nonlinear regression subroutine was used to fit the model. The technique is demonstrated using Northeast Fisheries Center bottom trawl survey data as a measure of relative abundance. Fitting was carried out for four fish populations: Georges Bank and Southern New England yellowtail flounder (Limanda ferruginea); Georges Bank and NAFO SA 4X haddock (Melanogrammus aeglefinus). Catchability coefficients calculated in this manner are consistent with prior estimates. In addition, the technique smooths the survey data by filtering measurement error from true fluctuations in population size. Population size estimates for haddock derived by this method agree closely with virtual population analysis (VPA) estimates.
Hydrologic Control of Lake Susceptibility to Acidification
Authors: Eilers J. M. , Glass G. E. , Webster K. E. , Rogalla J. A.
Published: April 2008

Two hundred and seventy-five lakes were sampled in the summer of 1979 to assess the factors controlling susceptibility of northcentral Wisconsin lakes to acidification. In addition to direct evaluation of means and ranges of the physical and chemical characteristics, a cluster analysis was carried out using alkalinity, color, and chlorophyll a data. Three well-defined clusters emerged that appeared to be controlled by hydrology: A — dominated by surface runoff; B — dominated by groundwater; C — dominated by precipitation. Relationships between morphometric, hydrologic, and terrigenous factors that can influence lake water quality and susceptibility were further examined by discriminant analysis of 18 watershed properties across the three lake clusters. Hydrologic factors were most important in differentiating the low alkalinity and high alkalinity lakes. The potentially sensitive low alkalinity lakes in northcentral Wisconsin lack surface inlets or outlets and their chemistry is closely associated with precipitation chemistry.
Effect of Somatic Growth and Reproduction on Biomass Transfer up Pelagic Food Webs as Calculated from Particle-Size-Conversion Efficiency
Authors: Borgmann Uwe
Published: April 2008

Biomass or energy transfer up pelagic food webs to larger sized organisms is a function of (1) direct trophic level transfer through predation, (2) somatic growth, a process that augments biomass transfer through predation, and (3) reproduction, which impedes biomass transfer by moving biomass down the food web to smaller sizes. By assuming that particle-size-conversion efficiency (log (food consumed/biomass produced)/log (predator–prey size ratio)) is relatively constant, I derive simple equations to calculate the effect of somatic growth and reproduction on biomass transfer up the food web. This defines the conditions under which somatic growth and reproduction can be ignored and biomass flow can be calculated from predation alone, using a previously developed model. When these conditions are not met, the effect of somatic growth and reproduction can be calculated from data on cohort growth and mortality rates. It is not necessary to identify the food of any species. This eliminates one of the problems often encountered when modeling food webs. I have applied these equations to production of Mysis relicta. If the estimates of Mysis abundance and growth rates are correct, then size-corrected production is about 25% greater for this species when somatic growth is accounted for in the calculations. This is because mortality of young Mysis appears to be low and most production occurs during somatic growth and not during reproduction.
Sexual Dimorphism in the Adipose Fin of Pacific Salmon (Oncorhynchus)
Authors: Beacham Terry D. , Murray Clyde B.
Published: April 2008

Male adipose fins of Oncorhynchus species were 30–50% larger than those of same-sized females, the actual amount depending on the species. Accuracy of classification of the standards ranged from 87% in chinook salmon (O. tshawytscha) to 98% in pink salmon (O. gorbuscha). Testing the method on new samples usually resulted in an accuracy of at least 90% correct identification of sex for any species. Relative size of the adipose fin should allow for easy and accurate external identification of the sexes of silver-bright Oncorhynchus.
Downstream and Lateral Transport of Nymphs of Two Mayfly Species (Ephemeroptera)
Authors: Ciborowski Jan J. H.
Published: April 2008

By releasing live and dead nymphs of two mayfly species, Baetis tricaudatus Dodds and Ephemerella inermis Eaton, into the water column of a river and catching them downstream in a series of contiguous nets, I estimated settling and lateral dispersal rates. Live animals settled over shorter distances than dead individuals, and became more widely laterally dispersed for any given distance downstream and mean current velocity. Transport of suspended organisms in a river in which mean current velocity increases with increasing distance from shore may produce a skewed cross-river benthic distribution of animals. The degree of skewness will depend on the current velocity gradient and on suspended animals' settling behavior.
Cystidicola farionis (Nematoda) as an Indicator of Lake Trout (Salvelinus namaycush) of Bering Ancestry
Authors: Black Geoff A.
Published: April 2008

Cystidicola farionis Fischer is widely distributed in fishes in northern North America west of the Appalachian Mountains. The swimbladders of lake trout (Salvelinus namaycush) from 225 localities across North America were examined for the parasite but only those from the Alsek, Coppermine, Flat, Peel, Stikine, Upper Liard, and Yukon River systems were infected with mature nematodes. The ancestors of fishes in these watersheds survived glaciation in a Bering refugiurn. Thus, this strain of C. farionis probably had a refugium in Beringia in the unglaciated parts of the Yukon River system and dispersed from there into northern British Columbia and the coastal mainland of the Northwest Territories during glacial retreat.
HEALTH SYSTEM REFORM IN CHINA: AN ASSESSMENT OF RECENT TRENDS
Authors: BLOMQVIST ǺKE , QIAN JIWEI
Published: April 2008

In this paper, we first briefly review the changes that the Chinese health care system has undergone since the early 1980s. We then describe the major current health policy initiatives in urban and rural areas and discuss likely scenarios for their evolution over time. Using comparisons with international experience regarding different institutional arrangements in the health care sector, we also discuss whether the approaches taken in China are likely to strengthen the health care system in terms of efficiency and equity. Our conclusion is that in order to predict how effectively China's future health care system will perform in the future, one must have more information about what role the state (central government) will play, as regulator, partial funder and direct provider in the system. We believe that the best strategy at present is to allow the development of a mixed model with significant roles for both the state and the private sector, in both the supply of health care services and the provision of health insurance.
COST CONTAINMENT AND ACCESS TO CARE: THE SHANGHAI HEALTH CARE FINANCING MODEL
Authors: DONG WEIZHEN
Published: April 2008

The medical savings account (MSA) model of health care financing is viewed as a health care cost containment strategy. Yet, health care expenditure in Shanghai has increased sharply since the adoption of the MSA system. This paper looks into the health care reforms in Shanghai, especially since the introduction of the MSA scheme.

From the Labor Insurance Scheme and Government Insurance Scheme to the Medical Savings Account scheme, ordinary Shanghai residents have not benefited from the most recent health care reforms. They have found medical care much less affordable. Disparity in access to health care access has become more evident than ever. Meanwhile, health care cost has increased sharply. China has benefited from an emphasis on prevention and primary care, but the government's recent policies give a high priority to catastrophic disease. This is not a cost-effective approach. Shanghai's health care system needs to break socioeconomic class boundaries if it is to construct a harmonious society. Shanghai's decision makers and various stakeholders have the resources and wisdom to face the challenge.
LOCATION, LOCATION, LOCATION: SELECTING SITES FOR CONTROVERSIAL FACILITIES
Authors: ALDRICH DANIEL P.
Published: April 2008

While a large literature exists on the siting of controversial facilities, few theories about spatial location have been tested on large samples. Using a new dataset from Japan, this paper demonstrates that state agencies choose localities judged weakest in local civil society as host communities for controversial projects. In some cases, powerful politicians deliberately seek to have facilities such as nuclear power plants, dams and airports placed in their home constituency. This paper then explores new territory: how demographic, political and civil society factors impact the outcomes of siting attempts. It finds that the strength of local civil society impacts the probability that a proposed project will come to fruition; the greater the concentration of local civil society, the less likely state-planned projects will be completed.
A MAP CHARACTERIZING THE FUZZY POINTS AND COLUMNS OF A T-INDISTINGUISHABILITY OPERATOR
Authors: RECASENS J. , BOIXADER D.
Published: April 2008

A new map (ΛE) between fuzzy subsets of a universe X endowed with a T-indistinguishability operator E is introduced. The main feature of ΛE is that it has the columns of E as fixed points, and thus it provides us with a new criterion to decide whether a generator is a column. Two well known maps (φE and ψE) are also reviewed, in order to compare them with ΛE. Interesting properties of the fixed points of φE and [Formula: see text] are studied. Among others, the fixed points of ΛE ( Fix (ΛE)) are proved to be the maximal fuzzy points of (X, E) and the fixed points of [Formula: see text] coincide with the Image of ΛE. An isometric embedding of X into Fix (ΛE) is established and studied.
STRICT FUZZY ORDERINGS WITH A GIVEN CONTEXT OF SIMILARITY
Authors: BODENHOFER ULRICH , DEMIRCI MUSTAFA
Published: April 2008

This paper introduces strict fuzzy orderings in the framework of similarity-based fuzzy orderings, i.e. where a context of similarity/indistinguishability is given by means of a fuzzy equivalence relation. We consider how to construct strict fuzzy orderings from partial fuzzy orderings and vice versa. The appropriateness of the concepts introduced in this paper is underlined by theoretical results and examples. We observe that the strongest results are achieved if the underlying triangular norm induces an involutive residual negation.
FUZZY CLUSTERING OF FEATURE VECTORS WITH SOME ORDINAL VALUED ATTRIBUTES USING GRADIENT DESCENT FOR LEARNING
Authors: BROUWER ROELOF K.
Published: April 2008

There are well established methods for fuzzy clustering especially for the cases where the feature values are numerical of ratio or interval scale. Not so well established are methods to be applied when the feature values are ordinal or nominal. In that case there is no one best method it seems. This paper discusses a method where unknown numeric variables are assigned to the ordinal values. Part of minimizing an objective function for the clustering is to find numeric values for these variables. Thus real numbers of interval scale and even ratio scale for that matter are assigned to the original ordinal values. The method uses the same objective function as used in fuzzy c-means clustering but both the membership function and the ordinal to real mapping are determined by gradient descent. Since the ordinal to real mapping is not known it cannot be verified for its legitimacy. However the ordinal to real mapping that is found is best in terms of the clustering produced. Simulations show the method to be quite effective.
FUZZY LINEAR AND POLYNOMIAL REGRESSION MODELLING OF ‘IF-THEN’ FUZZY RULEBASE
Authors: CHAKRABORTY CHANDAN , CHAKRABORTY DEBJANI
Published: April 2008

In developing so called fuzzy expert systems, fuzzy rule bases have been considered with greater importance. In fact, a fuzzy rule base is a knowledgebase that models human cognitive factors. Fuzzy rules are linguistic ‘IF-THEN’ constructions where ‘IF’ part consists of a set of fuzzy variables and ‘THEN’ part includes a dependent fuzzy variable. In order to identify the underlying mathematical structure in the fuzzy rule base, we develop fuzzy linear and fuzzy polynomial regression techniques in this paper. And the estimation of model parameters is also shown using least-square approach. Finally, examples are illustrated to demonstrate the proposed model.
ESTIMATES ON THE GREEN FUNCTION AND EXISTENCE OF POSITIVE SOLUTIONS FOR SOME NONLINEAR POLYHARMONIC PROBLEMS OUTSIDE THE UNIT BALL
Authors: BACHAR IMED , MÂAGLI HABIB , ZEDDINI NOUREDDINE
Published: April 2008

Let [Formula: see text] be the Green function of (-Δ)m, m ≥ 1, on the complementary D of the unit closed ball in ℝn, n ≥ 2, with Dirichlet boundary conditions [Formula: see text], 0 ≤ j ≤ m - 1. We establish some estimates on [Formula: see text] including the 3G-Inequality given by (1.3). Next, we introduce a polyharmonic Kato class of functions [Formula: see text] and we exploit the properties of this class to study the existence of positive solutions of some polyharmonic nonlinear elliptic problems.
MIXED GEVREY ASYMPTOTICS
Authors: OLDE DAALHUIS A. B.
Published: April 2008

In this paper, we illustrate with two examples that the computation of Stokes multipliers in problems in which the asymptotic expansions are not of Gevrey order one, is much more complicated and that the singularities in the corresponding Borel plane can be essential singularities.
TEMPORALLY GLOBAL SOLUTION TO THE EQUATIONS FOR A SPHERICALLY SYMMETRIC VISCOUS RADIATIVE AND REACTIVE GAS OVER THE RIGID CORE
Authors: UMEHARA MORIMICHI , TANI ATUSI
Published: April 2008

In this paper, we consider a system of classical model equations describing a motion of gaseous star, spherically symmetric, with a free-surface and a rigid core in the center under the influence of gaseous self-gravitation and potential force of the core. In addition to it, we investigate the above model equations in the physically more realistic situation: the presence of radiation and reacting process. By introducing Lagrangian mass coordinate, this free-boundary problem is reduced to the one in a fixed domain. Based on the fundamental local existence result and a priori estimates, we can construct a unique global classical solution.
Reversible logic synthesis with Fredkin and Peres gates
Authors: Donald James , Jha Niraj K.
Published: April 2008

Reversible logic has applications in low-power computing and quantum computing. Most reversible logic synthesis methods are tied to particular gate types, and cannot synthesize large functions. This article extends RMRLS, a reversible logic synthesis tool, to include additional gate types. While classic RMRLS can synthesize functions using NOT, CNOT, and
n
-bit Toffoli gates, our work details the inclusion of
n
-bit Fredkin and Peres gates. We find that these additional gates reduce the average gate count for three-variable functions from 6.10 to 4.56, and improve the synthesis results of many larger functions, both in terms of gate count and quantum cost.
High parallelism, portability, and broad accessibility
Authors: Guiducci Carlotta , Nardini Christine
Published: April 2008

Biotechnology is an area of great innovations that promises to have deep impact on everyday life thanks to profound changes in biology, medicine, and health care. This article will span from the description of the biochemical principles of molecular biology to the definition of the physics that supports the technology and to the devices and algorithms necessary to observe molecular events in a controlled, portable, and highly parallel manner. Throughout this discussion, constant attention will be given to the ultimate goals and applications of these innovations as well as to the related issues.
Detecting cuts in sensor networks
Authors: Shrivastava Nisheeth , Suri Subhash , Tóth Csaba D.
Published: April 2008

We propose a low-overhead scheme for detecting a network partition or cut in a sensor network. Consider a network
S
of
n
sensors, modeled as points in a two-dimensional plane. An ε-
cut
, for any 0 < ε < 1, is a linear separation of ε
n
nodes in
S
from a distinguished node, the
base station
. Our main result is that, by monitoring the status of just
O
(1/ε) nodes in the network, the base station can detect whenever an ε-
cut
occurs. Furthermore, this detection comes with a deterministic guarantee that every reported cut has size at least ε
n
/2. Besides this combinatorial result, we also propose efficient algorithms for finding the
O
(1/ε) nodes that should act as
sentinels
, and report on our simulation results, comparing the sentinel algorithm with two natural schemes based on random sampling.
Developmental stage annotation of Drosophila gene expression pattern images via an entire solution path for LDA
Authors: Ye Jieping , Chen Jianhui , Janardan Ravi , Kumar Sudhir
Published: April 2008

Gene expression in a developing embryo occurs in particular cells (spatial patterns) in a time-specific manner (temporal patterns), which leads to the differentiation of cell fates. Images of aDrosophila melanogasterembryo at a given developmental stage, showing a particular gene expression pattern revealed by a gene-specific probe, can be compared for spatial overlaps. The comparison is fundamentally important to formulating and testing gene interaction hypotheses. Expression pattern comparison is most biologically meaningful when images from a similar time point (developmental stage) are compared. In this paper, we present LdaPath, a novel formulation of Linear Discriminant Analysis (LDA) for automatic developmental stage range classification. It employs multivariate linear regression with theL1-norm penalty controlled by a regularization parameter for feature extraction and visualization. LdaPath computes an entire solution path for all values of regularization parameter with essentially the same computational cost as fitting one LDA model. Thus, it facilitates efficient model selection. It is based on the equivalence relationship between LDA and the least squares method for multiclass classifications. This equivalence relationship is established under a mild condition, which we show empirically to hold for many high-dimensional datasets, such as expression pattern images. Our experiments on a collection of 2705 expression pattern images show the effectiveness of the proposed algorithm. Results also show that the LDA model resulting from LdaPath is sparse, and irrelevant features may be removed. Thus, LdaPath provides a general framework for simultaneous feature selection and feature extraction.
A comprehensive combination framework
Authors: Ghilardi Silvio , Nicolini Enrica , Zucchelli Daniele
Published: April 2008

We define a general notion of a fragment within higher-order type theory; a procedure for constraint satisfiability in combined fragments is outlined, following Nelson-Oppen schema. The procedure is in general only sound, but it becomes terminating and complete when the shared fragment enjoys suitable noetherianity conditions and admits an abstract version of a “Keisler-Shelah-like” isomorphism theorem. We show that this general decidability transfer result covers recent work on combination in first-order theories as well as in various intensional logics such as description, modal, and temporal logics.
Bounds on the automata size for Presburger arithmetic
Authors: Klaedtke Felix
Published: April 2008

Automata provide a decision procedure for Presburger arithmetic. However, until now only crude lower and upper bounds were known on the sizes of the automata produced by the automata-based approach for Presburger arithmetic. In this article, we give an upper bound on the number of states of the minimal deterministic automaton for a Presburger arithmetic formula. This bound depends on the length of the formula and the quantifiers occurring in it. We establish the upper bound by comparing the automata for Presburger arithmetic formulas with the formulas produced by a quantifier-elimination method. We show that our bound is tight, also for nondeterministic automata. Moreover, we provide automata constructions for atomic formulas and establish lower bounds for the automata for linear equations and inequations.