bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Applied Volume on Efficacy of 3-Minute Surgical Reference Disinfection Method prEN 12791
Authors: Kampf Günter , Ostermeyer Christiane
Published: December 2004

For assessment of the efficacy of surgical hand disinfection, European reference method prEN 12791 prescribes that the hands must be kept wet with the reference alcohol for 3 min regardless of the applied volume. The aim of this study was to determine whether the applied volume of the reference disinfectant
n
-propanol (60%, vol/vol) influences the effect on the resident hand flora. Ten experiments with 200 reference disinfections were analyzed. Hands were washed for 1 min with soap. The bacterial prevalue was obtained by rubbing fingertips in tryptic soy broth for 1 min. After this, each subject treated the hands with
n
-propanol (60%, vol/vol) by using as many portions as necessary to keep hands wet for a total of 3 min. Bacterial postvalues (immediate effect) were obtained for one hand, and the other hand was gloved for 3 h. After the gloves were taken off, a second postvalue was obtained (sustained effect). Most surgical reference disinfections (73%) were achieved with 9 ml of the reference alcohol, followed by 12 ml (24%) and 6 ml (3%). There was no significant difference between the mean log
10
reduction values for the three treatment groups, both in terms of the immediate effect (
P
= 0.333, as determined by analysis of variance) and in terms of the sustained effect (
P
= 0.442). A higher number of portions did not correlate with a higher reduction factor (for immediate effect, Pearson's correlation coefficient = −0.028 [
P
= 0.689]; for sustained effect, Pearson's correlation coefficient = 0.059 [
P
= 0.404]). If the hands were kept wet with the reference alcohol for the total application time, the applied volume could vary, but this did not alter the efficacy.
Survival of Cold-Stressed
Campylobacter jejuni
on Ground Chicken and Chicken Skin during Frozen Storage
Authors: Bhaduri Saumya , Cottrell Bryan
Published: December 2004

Campylobacter jejuni
is prevalent in poultry, but the effect of combined refrigerated and frozen storage on its survival, conditions relevant to poultry processing and storage, has not been evaluated. Therefore, the effects of refrigeration at 4°C, freezing at −20°C, and a combination of refrigeration and freezing on the survival of
C. jejuni
in ground chicken and on chicken skin were examined. Samples were enumerated using tryptic soy agar containing sheep's blood and modified cefoperazone charcoal deoxycholate agar. Refrigerated storage alone for 3 to 7 days produced a reduction in cell counts of 0.34 to 0.81 log
10
CFU/g in ground chicken and a reduction in cell counts of 0.31 to 0.63 log
10
CFU/g on chicken skin. Declines were comparable for each sample type using either plating medium. Frozen storage, alone and with prerefrigeration, produced a reduction in cell counts of 0.56 to 1.57 log
10
CFU/g in ground chicken and a reduction in cell counts of 1.38 to 3.39 log
10
CFU/g on chicken skin over a 2-week period. The recovery of
C. jejuni
following freezing was similar on both plating media. The survival following frozen storage was greater in ground chicken than on chicken skin with or without prerefrigeration. Cell counts after freezing were lower on chicken skin samples that had been prerefrigerated for 7 days than in those that had been prerefrigerated for 0, 1, or 3 days. This was not observed for ground chicken samples, possibly due to their composition.
C. jejuni
survived storage at 4 and −20°C with either sample type. This study indicates that, individually or in combination, refrigeration and freezing are not a substitute for safe handling and proper cooking of poultry.
Restoration of Gene Function by Homologous Recombination: from PCR to Gene Expression in One Step
Authors: Yosef Ido , Bloushtain Noga , Shapira Michal , Qimron Udi
Published: December 2004

We have developed a simple method for single-step cloning of any PCR product into a plasmid. A novel selection principle has been applied, in which activation of a drug selection marker is achieved following homologous recombination. In this method a DNA fragment is amplified by PCR with standard oligonucleotides that contain flanking tails derived from the host plasmid and the complete λP
R
or
rrnA1
promoter regions. The resulting PCR product is then electroporated into an
Escherichia coli
strain harboring both the phage λ Red functions and the host plasmid. Upon homologous recombination of the PCR fragment into the plasmid, expression of a drug selection marker is fully induced due to restoration of its truncated promoter, thus allowing appropriate selection. Recombinant plasmid vectors encoding β-galactosidase and neomycin phosphotransferase were constructed by using this method in two well-known Red systems. This cloning strategy significantly reduces both the time and costs associated with cloning procedures.
Development of a Universal Microarray Based on the Ligation Detection Reaction and 16S rRNA Gene Polymorphism To Target Diversity of Cyanobacteria
Authors: Castiglioni Bianca , Rizzi Ermanno , Frosini Andrea , Sivonen Kaarina , Rajaniemi Pirjo , Rantala Anne , Mugnai Maria Angela , Ventura Stefano , Wilmotte Annick , Boutte Christophe , Grubisic Stana , Balthasart Pierre , Consolandi Clarissa , Bordoni Roberta , Mezzelani Alessandra , Battaglia Cristina , De Bellis Gianluca
Published: December 2004

The cyanobacteria are photosynthetic prokaryotes of significant ecological and biotechnological interest, since they strongly contribute to primary production and are a rich source of bioactive compounds. In eutrophic fresh and brackish waters, their mass occurrences (water blooms) are often toxic and constitute a high potential risk for human health. Therefore, rapid and reliable identification of cyanobacterial species in complex environmental samples is important. Here we describe the development and validation of a microarray for the identification of cyanobacteria in aquatic environments. Our approach is based on the use of a ligation detection reaction coupled to a universal array. Probes were designed for detecting 19 cyanobacterial groups including
Anabaena
/
Aphanizomenon
,
Calothrix
,
Cylindrospermopsis
,
Cylindrospermum
,
Gloeothece
, halotolerants,
Leptolyngbya
, Palau
Lyngbya
,
Microcystis
,
Nodularia
,
Nostoc
,
Planktothrix
, Antarctic
Phormidium
,
Prochlorococcus
,
Spirulina
,
Synechococcus
,
Synechocystis
,
Trichodesmium
, and
Woronichinia
. These groups were identified based on an alignment of over 300 cyanobacterial 16S rRNA sequences. For validation of the microarrays, 95 samples (24 axenic strains from culture collections, 27 isolated strains, and 44 cloned fragments recovered from environmental samples) were tested. The results demonstrated a high discriminative power and sensitivity to 1 fmol of the PCR-amplified 16S rRNA gene. Accurate identification of target strains was also achieved with unbalanced mixes of PCR amplicons from different cyanobacteria and an environmental sample. Our universal array method shows great potential for rapid and reliable identification of cyanobacteria. It can be easily adapted to future development and could thus be applied both in research and environmental monitoring.
Prevalence and Characterization of Shiga Toxin-Producing
Escherichia coli
in Swine Feces Recovered in the National Animal Health Monitoring System's Swine 2000 Study
Authors: Fratamico Pina M. , Bagi Lori K. , Bush Eric J. , Solow Barbara T.
Published: December 2004

A study was conducted to determine the prevalence of Shiga toxin-producing
Escherichia coli
(STEC) in swine feces in the United States as part of the National Animal Health Monitoring System's Swine 2000 study. Fecal samples collected from swine operations from 13 of the top 17 swine-producing states were tested for the presence of STEC. After enrichment of swine fecal samples in tryptic soy broth, the samples were tested for the presence of
stx
1
and
stx
2
by use of the TaqMan
E. coli
STX1 and STX2 PCR assays. Enrichments of samples positive for
stx
1
and/or
stx
2
were plated, and colony hybridization was performed using digoxigenin-labeled probes complementary to the
stx
1
and
stx
2
genes. Positive colonies were picked and confirmed by PCR for the presence of the
stx
1
,
stx
2
, or
stx
2e
genes, and the isolates were serotyped. Out of 687 fecal samples tested using the TaqMan assays, 70% (484 of 687) were positive for Shiga toxin genes, and 54% (370 of 687), 64% (436 of 687), and 38% (261 of 687) were positive for
stx
1
,
stx
2
, and both toxin genes, respectively. Out of 219 isolates that were characterized, 29 (13%) produced
stx
1
, 14 (6%) produced
stx
2
, and 176 (80%) produced
stx
2e
. Twenty-three fecal samples contained at least two STEC strains that had different serotypes but that had the same toxin genes or included a strain that possessed
stx
1
in addition to a strain that possessed
stx
2
or
stx
2e
. The STEC isolates belonged to various serogroups, including O2, O5, O7, O8, O9, OX10, O11, O15, OX18, O20, O57, O65, O68, O69, O78, O91, O96, O100, O101, O120, O121, O152, O159, O160, O163, and O untypeable. It is noteworthy that no isolates of serogroup O157 were recovered. Results of this study indicate that swine in the United States harbor STEC that can potentially cause human illness.
Prevalence and Seasonal Variations of Six Bee Viruses in
Apis mellifera
L. and
Varroa destructor
Mite Populations in France
Authors: Tentcheva Diana , Gauthier Laurent , Zappulla Nathalie , Dainat Benjamin , Cousserans François , Colin Marc Edouard , Bergoin Max
Published: December 2004

A survey of six bee viruses on a large geographic scale was undertaken by using seemingly healthy bee colonies and the PCR technique. Samples of adult bees and pupae were collected from 36 apiaries in the spring, summer, and autumn during 2002.
Varroa destructor
samples were collected at the end of summer following acaricide treatment. In adult bees, during the year deformed wing virus (DWV) was found at least once in 97% of the apiaries, sacbrood virus (SBV) was found in 86% of the apiaries, chronic bee paralysis virus (CBPV) was found in 28% of the apiaries, acute bee paralysis virus (ABPV) was found in 58% of the apiaries, black queen cell virus (BQCV) was found in 86% of the apiaries, and Kashmir bee virus (KBV) was found in 17% of the apiaries. For pupae, the following frequencies were obtained: DWV, 94% of the apiaries; SBV, 80% of the apiaries; CBPV, none of the apiaries; ABPV, 23% of the apiaries; BQCV, 23% of the apiaries; and KBV, 6% of the apiaries. In
Varroa
samples, the following four viruses were identified: DWV (100% of the apiaries), SBV (45% of the apiaries), ABPV (36% of the apiaries), and KBV (5% of the apiaries). The latter findings support the putative role of mites in transmitting these viruses. Taken together, these data indicate that bee virus infections occur persistently in bee populations despite the lack of clinical signs, suggesting that colony disease outbreaks might result from environmental factors that lead to activation of viral replication in bees.
Differentiation of the Gene Clusters Encoding Botulinum Neurotoxin Type A Complexes in
Clostridium botulinum
Type A, Ab, and A(B) Strains
Authors: Franciosa Giovanna , Floridi Francesca , Maugliani Antonella , Aureli Paolo
Published: December 2004

We describe a strategy to identify the clusters of genes encoding components of the botulinum toxin type A (boNT/A) complexes in 57 strains of
Clostridium botulinum
types A, Ab, and A(B) isolated in Italy and in the United States from different sources. Specifically, we combined the results of PCR for detecting the
ha33
and/or
p47
genes with those of
boNT/A
PCR-restriction fragment length polymorphism analysis. Three different type A toxin gene clusters were revealed; type A1 was predominant among the strains from the United States, whereas type A2 predominated among the Italian strains, suggesting a geographic distinction between strains. By contrast, no relationship between the toxin gene clusters and the clinical or food source of strains was evident. In two
C. botulinum
type A isolates from the United States, we recognized a third type A toxin gene cluster (designated type A3) which was similar to that previously described only for
C. botulinum
type A(B) and Ab strains. Total genomic DNA from the strains was subjected to pulsed-filed gel electrophoresis and randomly amplified polymorphic DNA analyses, and the results were consistent with the
boNT/A
gene clusters obtained.
Occurrence of Microbial Indicators and
Clostridium perfringens
in Wastewater, Water Column Samples, Sediments, Drinking Water, and Weddell Seal Feces Collected at McMurdo Station, Antarctica
Authors: Lisle John T. , Smith James J. , Edwards Diane D. , McFeters Gordon A.
Published: December 2004

McMurdo Station, Antarctica, has discharged untreated sewage into McMurdo Sound for decades. Previous studies delineated the impacted area, which included the drinking water intake, by using total coliform and
Clostridium perfringens
concentrations. The estimation of risk to humans in contact with the impacted and potable waters may be greater than presumed, as these microbial indicators may not be the most appropriate for this environment. To address these concerns, concentrations of these and additional indicators (fecal coliforms,
Escherichia coli
, enterococci, coliphage, and enteroviruses) in the untreated wastewater, water column, and sediments of the impacted area and drinking water treatment facility and distribution system at McMurdo Station were determined. Fecal samples from Weddell seals in this area were also collected and analyzed for indicators. All drinking water samples were negative for indicators except for a single total coliform-positive sample. Total coliforms were present in water column samples at higher concentrations than other indicators. Fecal coliform and enterococcus concentrations were similar to each other and greater than those of other indicators in sediment samples closer to the discharge site.
C. perfringens
concentrations were higher in sediments at greater distances from the discharge site. Seal fecal samples contained concentrations of fecal coliforms,
E. coli
, enterococci, and
C. perfringens
similar to those found in untreated sewage. All samples were negative for enteroviruses. A wastewater treatment facility at McMurdo Station has started operation, and these data provide a baseline data set for monitoring the recovery of the impacted area. The contribution of seal feces to indicator concentrations in this area should be considered.
Molecular Characterization of a Dechlorinating Community Resulting from In Situ Biostimulation in a Trichloroethene-Contaminated Deep, Fractured Basalt Aquifer and Comparison to a Derivative Laboratory Culture
Authors: Macbeth Tamzen W. , Cummings David E. , Spring Stefan , Petzke Lynn M. , Sorenson Kent S.
Published: December 2004

Sodium lactate additions to a trichloroethene (TCE) residual source area in deep, fractured basalt at a U.S. Department of Energy site have resulted in the enrichment of the indigenous microbial community, the complete dechlorination of nearly all aqueous-phase TCE to ethene, and the continued depletion of the residual source since 1999. The bacterial and archaeal consortia in groundwater obtained from the residual source were assessed by using PCR-amplified 16S rRNA genes. A clone library of bacterial amplicons was predominated by those from members of the classClostridia(57 of 93 clones), of which a phylotype most similar to that of the homoacetogenAcetobacteriumsp. strain HAAP-1 was most abundant (32 of 93 clones). The remainingBacteriaconsisted of phylotypes affiliated withSphingobacteria,Bacteroides,Spirochaetes,Mollicutes, andProteobacteriaand candidate divisions OP11 and OP3. The two proteobacterial phylotypes were most similar to those of the known dechlorinatorsTrichlorobacter thiogenesandSulfurospirillum multivorans. Although not represented by the bacterial clones generated with broad-specificity bacterial primers, aDehalococcoides-like phylotype was identified with genus-specific primers. Only four distinct phylotypes were detected in the groundwater archaeal library, including predominantly a clone affiliated with the strictly acetoclastic methanogenMethanosaeta concilii(24 of 43 clones). A mixed culture that completely dechlorinates TCE to ethene was enriched from this groundwater, and both communities were characterized by terminal restriction fragment length polymorphism (T-RFLP). According to T-RFLP, the laboratory enrichment community was less diverse overall than the groundwater community, with 22 unique phylotypes as opposed to 43 and a higher percentage ofClostridia, including theAcetobacteriumpopulation. Bioreactor archaeal structure was very similar to that of the groundwater community, suggesting that methane is generated primarily via the acetoclastic pathway, using acetate generated by lactate fermentation and acetogenesis in both systems.
Complete Nucleotide Sequence of the Conjugative Tetracycline Resistance Plasmid pFBAOT6, a Member of a Group of IncU Plasmids with Global Ubiquity
Authors: Rhodes Glenn , Parkhill Julian , Bird Christine , Ambrose Kerrie , Jones Matthew C. , Huys Geert , Swings Jean , Pickup Roger W.
Published: December 2004

This study presents the first complete sequence of an IncU plasmid, pFBAOT6. This plasmid was originally isolated from a strain of
Aeromonas caviae
from hospital effluent (Westmorland General Hospital, Kendal, United Kingdom) in September 1997 (G. Rhodes, G. Huys, J. Swings, P. McGann, M. Hiney, P. Smith, and R. W. Pickup, Appl. Environ. Microbiol.
66:
3883-3890, 2000) and belongs to a group of related plasmids with global ubiquity. pFBAOT6 is 84,748 bp long and has 94 predicted coding sequences, only 12 of which do not have a possible function that has been attributed. Putative replication, maintenance, and transfer functions have been identified and are located in a region in the first 31 kb of the plasmid. The replication region is poorly understood but exhibits some identity at the protein level with replication proteins from the gram-positive bacteria
Bacillus
and
Clostridium
. The mating pair formation system is a
virB
homologue, type IV secretory pathway that is similar in its structural organization to the mating pair formation systems of the related broad-host-range (BHR) environmental plasmids pIPO2, pXF51, and pSB102 from plant-associated bacteria. Partitioning and maintenance genes are homologues of genes in IncP plasmids. The DNA transfer genes and the putative
oriT
site also exhibit high levels of similarity with those of plasmids pIPO2, pXF51, and pSB102. The genetic load region encompasses 54 kb, comprises the resistance genes, and includes a class I integron, an IS
630
relative, and other transposable elements in a 43-kb region that may be a novel Tn
1721
-flanked composite transposon. This region also contains 24 genes that exhibit the highest levels of identity to chromosomal genes of several plant-associated bacteria. The features of the backbone of pFBAOT6 that are shared with this newly defined group of environmental BHR plasmids suggest that pFBAOT6 may be a relative of this group, but a relative that was isolated from a clinical bacterial environment rather than a plant-associated bacterial environment.
Flow Cytometry-Assisted Cloning of Specific Sequence Motifs from Complex 16S rRNA Gene Libraries
Authors: Nielsen Jeppe L. , Schramm Andreas , Bernhard Anne E. , van den Engh Gerrit J. , Stahl David A.
Published: December 2004

A flow cytometry method was developed for rapid screening and recovery of cloned DNA containing common sequence motifs. This approach, termed fluorescence-activated cell sorting-assisted cloning, was used to recover sequences affiliated with a unique lineage within the
Bacteroidetes
not abundant in a clone library of environmental 16S rRNA genes.
Reproductive and therapeutic cloning, germline therapy, and purchase of gametes and embryos: comments on Canadian legislation governing reproduction technologies
Authors: Bernier L , Grégoire D
Published: December 2004

In Canada, the Assisted Human Reproduction Act received royal assent on 29 March 2004. The approach proposed by the federal government responds to Canadians’ strong desire for an enforceable legislative framework in the field of reproduction technologies through criminal law. As a result of the widening gap between the rapid pace of technological change and governing legislation, a distinct need was perceived to create a regulatory framework to guide decisions regarding reproductive technologies.

In this article the three main topics covered in the new legislation are commented on: cloning, germline therapy, and purchase of gametes and embryos. Some important issues also covered in the new legislation, such as privacy and access to information, data protection, identity of donors, and inspection, will not be addressed.
Presenting behavioural genetics: spin, ideology, and our narrative interests
Authors: Manson N C
Published: December 2004

A short review is given of the Nuffield Council’s report on behavioural genetics. This review is used as an entry point to a discussion of the factors that influence the presentation of behavioural genetics in the media and in the popular scientific press. It is argued that our interest in formulating narrative explanations of our individual lives puts pressure on publishers and editors to present behavioural genetics in a selective, misleading, way. Some other influences on presentation are discussed and it is suggested that the Nuffield report is particularly useful in so far as it lacks these distorting influences.
Obtaining explicit consent for the use of archival tissue samples: practical issues
Authors: Furness P N , Nicholson M L
Published: December 2004

Background::Over the past few years, research ethics committees have increasingly demanded explicit consent before archival tissue samples can be used in research projects. Current UK guidance in this area requires an assessment of whether it is “practical” to obtain explicit consent. Ethics committees have little experience or evidence to help them to judge what is “practical” in this context.

Methods::We attempted to obtain general consent for research use of surplus tissue from renal transplant biopsies from the entire patient population of the renal transplant unit in Leicester. The nature of this patient population would be expected to facilitate this task.

Results::A total of 495 letters were sent. Attempts were made to contact non-responders when they attended the outpatient clinic. One year after the initiation of the project, the opinions of 26% of the patients had still not been ascertained.

Conclusions::The results confirm that the vast majority of patients are happy for “surplus” biopsy material to be used for research; the situation does not parallel the use of autopsy tissue. A requirement to obtain explicit consent for the study of archival tissue is likely, however, to block or at least seriously delay research, which is contrary to the public interest and specifically may harm the interests of the patients concerned. In the UK, the problem of tissue being used against the wishes of the donor has now been largely replaced by the problem ofprohibitionof tissue use against the wishes of the donor.
Bioterrorism and smallpox planning: information and voluntary vaccination
Authors: Selgelid M J
Published: December 2004

Although smallpox was declared eradicated in 1980, there are fears that stocks of the virus manufactured for military purposes by the Soviet Union may have fallen into the hands of “rogue nations” or terrorists. Worries about bioterrorism have thus sparked debate about whether or not the smallpox vaccine, which can be dangerous, should be offered to the general public. Meaningful public debate on this issue requires expert information about the likelihood that the virus will in fact be used as a weapon. Informed voluntary individual decision making, about whether to get vaccinated if vaccine is made available to the public, would similarly require appreciation of the likelihood of attack. Public deliberation and private deliberation thus both require briefing by the intelligence community.
OPEN-LOOP AND CLOSED-LOOP MODELS OF DYNAMIC OLIGOPOLY IN THE CRUISE LINE INDUSTRY
Authors: WIE BYUNG-WOOK
Published: December 2004

In this paper, the competition of dynamic oligopoly in the cruise line industry is modeled as an N-person nonzero-sum noncooperative dynamic game where a finite number of cruise lines compete to maximize their profits over a fixed planning horizon. The noncooperative Nash equilibrium capacity investment strategies of cruise lines are theoretically analyzed under the open-loop and closed-loop information structures. The optimality conditions for open-loop and closed-loop Nash equilibrium solutions are derived using a Pontryagin-type maximum principle and given economic interpretations so as to demonstrate the differences between the open-loop and closed-loop Nash equilibrium solutions. The dynamic oligopolistic competition of three cruise lines in a hypothetical setting is numerically analyzed by using the iterative algorithms for open-loop and closed-loop models. Numerical results provide a number of important managerial guidelines for cruise capacity investment decisions. The paper concludes with a discussion on future research directions.
OPTIMIZATION OF COMPLEX SYSTEM RELIABILITY BY A MODIFIED GREAT DELUGE ALGORITHM
Authors: RAVI VADLAMANI
Published: December 2004

In this paper, a global optimization meta-heuristic, the great deluge algorithm, is extended and applied to optimize the reliability of complex systems. Two different kinds of optimization problems (i) Reliability optimization of a complex system with constraints on cost and weight (ii) Optimal redundancy allocation in a multi-stage mixed system with constraints on cost and weight are solved to demonstrate the effectiveness of the algorithm. A software developed in ANSI C, implements the algorithm. In terms of both accuracy and speed, it is observed that the present algorithm, the modified great deluge algorithm (MGDA) yielded far superior results compared to those obtained by the simulated annealing, the improved non-equilibrium simulated annealing and other optimization algorithms. Further, when both accuracy and speed are considered simultaneously, both MGDA and another meta-heuristic, ant colony optimization (ACO) yielded comparable results. In conclusion, the MGDA, can be used as an efficient alternative to ACO and other existing optimization techniques.
APPLYING METAHEURISTICS TO FEEDER BUS NETWORK DESIGN PROBLEM
Authors: KUAN S. N. , ONG H. L. , NG K. M.
Published: December 2004

This paper proposes the design and analysis of two metaheuristics, simulated annealing (SA) and tabu search (TS), for solving the feeder bus network design problem. The results are compared to those published in the literature. A comparative study is also carried out on several test problems generated at random to evaluate the performance of these heuristics in terms of their computational efficiency and solution quality. Computational experiments have shown that TS is a more effective metaheuristic in solving the problem than SA.
THE STRONG MAGNETIC FIELD DECAY AND EVOLUTION OF RADIO PULSARS ON THE P–Ṗ DIAGRAM
Authors: GUSEINOV OKTAY H. , ANKAY AŞKIN , TAGIEVA SEVINÇ O.
Published: December 2004

In this work we have analysed various data on radio pulsars and we have shown that magnetic field decay of a factor about 10–20 is necessary to explain their evolution, in particular to remove the discrepancy between the characteristic and the real ages. The character of the field decay is exponential with a characteristic time of about 3×106 year. Observational data on single X-ray pulsars which radiate due to cooling also support this result.
WMAP BOUNDS ON BRANEWORLD TACHYONIC INFLATION
Authors: BENTO M. C. , SANTOS N. M. C. , SEN A. A.
Published: December 2004

We analyze the implications of the Wilkinson Microwave Anisotropy Probe (WMAP) results for a braneworld tachyonic model of inflation. We find that WMAP bounds on ns allow us to constrain significantly the parameter space of the model; in particular, extremely weak string coupling is required, gs~10-15. Moreover, our analysis shows that the running of the scalar spectral index is within the bounds determined by WMAP for the allowed range of model parameters; however, it is not possible to obtain ns>1 on large scales and ns<1 on small scales.
PROPERTIES OF ACCRETION SHOCKS IN VISCOUS FLOWS WITH COOLING EFFECTS
Authors: DAS SANTABRATA , CHAKRABARTI SANDIP K.
Published: December 2004

Low angular momentum accretion flows can have standing and oscillating shock waves. We study the region of the parameter space in which multiple sonic points occur in viscous flows in presence of various cooling effects such as bremsstrahlung and Comptonization. We also quantify the parameter space in which shocks are steady or oscillating. We find that cooling induces effects opposite to heating by viscosity even in modifying the topology of the solutions, though one can never be exactly balanced by the other due to their dissimilar dependence on dynamic and thermodynamic parameters. We show that beyond a critical value of cooling, the flow ceases to contain a shock wave.
COSMOLOGY WITH NEGATIVE POTENTIALS WITH wϕ<-1
Authors: DE LA MACORRA A. , GERMÁN G.
Published: December 2004

We study the cosmology of canonically normalized scalar fields that lead to an equation of state parameter of wϕ=pϕ/ρϕ<-1 without violating the weak energy condition: ρ=Σiρi≥0 and ρi+pi≥0. This kind of behavior requires a negative scalar potential V, widely predicted in particle physics. We show that the energy density ρϕ=Ek+V takes negative values with an equation of state with wϕ<-1. However, the net effect of the ϕ field on the scale factor is to decelerate it giving a total equation of state parameter w=p/ρ>wb=pb/ρb, where ρb stands for any kind of energy density with -1≤wb≤1, such as radiation, matter, cosmological constant or other scalar field with a potential V≥0. The fact that ρϕ<0 allows, at least in principle, to have a small cosmological constant or quintessence today as the cancellation of high energy scales such as the electroweak or susy breaking scale. While V is negative |ρϕ| is smaller than the sum of all other energy densities regardless of the functional form of the potential V. We show that the existence of a negative potential leads, inevitable, to a collapsing universe, i.e. to a would be "big crunch." In this picture we would still be living in the expanding universe.
FLUCTUATIONS OF THE METRIC ENTROPY FOR MIXING MEASURES
Authors: HAYDN NICOLAI , VAIENTI SANDRO
Published: December 2004

It is known from the theorem of Shannon–McMillan–Breiman that the measure of cylinder sets decays in the limit exponentially with a rate which is given by the metric entropy. Here we prove that the measure of cylinders satisfies a Central Limit Theorem for a wide class of mixing measures which do not necessarily have the Gibbs property. We, moreover, provide the rate of convergence (which is algebraic). As a consequence we can then also prove that the distribution of the first return time in cylinder sets is log-normally distributed and give the speed of convergence. We also show that the weak invariance principle and the law of the iterated logarithm hold for the convergence to the entropy in the Shannon–McMillan–Breiman and for the distribution of the first return time.
AN OPTIMAL MARKOVIAN QUANTIZATION ALGORITHM FOR MULTI-DIMENSIONAL STOCHASTIC CONTROL PROBLEMS
Authors: PAGÈS GILLES , PHAM HUYÊN , PRINTEMS JACQUES
Published: December 2004

We propose a probabilistic numerical method based on optimal quantization to solve some multi-dimensional stochastic control problems that arise, for example, in mathematical finance for portfolio optimization. We then consider some controlled diffusions with most components control free. The Euler scheme of the uncontrolled diffusion part is approximated by a discrete time process obtained by a nearest neighbor projection on some grids optimally fitted to its dynamics. The resulting process is also designed to preserve the Markov property with respect to the filtration of the Euler scheme. This Markovian quantization approach leads to an approximate control problem that can be solved numerically by the dynamic programming formula. This approach seems promising in higher dimension. A prioriLp-error bounds are stated and we show that the spatial discretization error term is minimal at some specific grids. A simple recursive algorithm is devised to compute these optimal grids by induction based on a Monte Carlo simulation. Some numerical illustrations are processed for solving a mean-variance hedging problem.
VARIATIONAL ASYMPTOTIC DERIVATION OF AN ELASTIC MODEL ARISING FROM THE PROBLEM OF 3D AUTOMATIC SEGMENTATION OF CARDIAC IMAGES
Authors: FAUGERAS BLAISE , POUSIN JÉRÔME
Published: December 2004

Segmentation of 3D cardiac images using a deformable elastic model of the heart proved to be significantly improved by applying special boundary conditions on the elastic model [15]. The purpose of this paper is to derive those boundary conditions by means of a rigourous convergence result. We consider a simplified two-layer elastic shell model and show that when the thickness ε of the thin external fibrous layer tends to 0 it can be replaced by the above mentioned boundary conditions on the internal layer. A mixed variational formulation of the problem in curvilinear coordinates is introduced. This formulation is then scaled in order to be defined over an ε-independent domain. Finally, several a priori estimations on the solution are obtained which enable us to pass to the limit and prove our result.
THE N-WIDTHS OF HARDY–SOBOLEV AND BERGMAN–SOBOLEV SPACES OF COMPLEX VARIABLES
Authors: DING HONGMING
Published: December 2004

Let D be a bounded symmetric domain and Σ be the Shilov boundary of D. For R≥1, l∈ℤ+ and 1≤p≤∞, let DR=RD, Hp,l(DR) and Ap,l(DR) be the Hardy–Sobolev and Bergman–Sobolev spaces on DR, respectively. In this paper we show that the Kolmogorov, linear, Gel'fand, and Bernstein N-widths of Hp,l(DR) in Lp(Σ) all coincide, calculate the exact value, and identify optimal subspaces or optimal linear operators. We also do the same for N-widths of Ap,l(DR) in Lp(D). Moreover, we obtain new asymptotic estimates for the linear and Gel'fand N-widths of [Formula: see text] and [Formula: see text] in Lq(Sn) and Lq(Bn), where R>1, l∈ℤ+, 2≤p≤q≤∞, [Formula: see text], [Formula: see text] are the unit ball and unit sphere in [Formula: see text], respectively, and [Formula: see text]. Furthermore, we obtain asymptotic estimates for the linear and Gel'fand N-widths of Hp,l(DR) in Lq(Σ), where R>1, l∈ℤ+ and 2≤p≤q≤∞.
EXISTENCE OF BOUNDARY LAYER SOLUTIONS TO THE BOLTZMANN EQUATION
Authors: CHEN CHIUN-CHUAN , LIU TAI-PING , YANG TONG
Published: December 2004

In this paper, we consider the existence of boundary layer solutions to the Boltzmann equation for a hard potential with angular cut-off. The boundary condition is imposed for incoming particles of Dirichlet type and the solution tends to a global Maxwellian in the far field. Similar to the problem on the hard sphere model studied in [17], the existence of a solution is shown to depend on the Mach number of the far field Maxwellian, and there is an implicit solvability conditions yielding the co-dimensions of the boundary data. For hard potential models, the shape of the boundary layers is richer. This compels the introduction of a new norm which is a function of both position and velocity.
BROKEN AREA MODELING FOR REPAIR AUTOMATION
Authors: ZHENG JIANMING , LI ZHONGGUO , CHEN XI
Published: December 2004

Current repairing process for worn-out blades and blisks of aeroengines and industrial gas turbines is highly manual, labor experience-based and hence error-prone. It requires more sophisticated CNC-driven laser equipment to replace manual welding for the repair. This paper presents an innovative strategy that will lead to the automation of laser welding and cladding. The project makes use of reverse engineering techniques to capture the geometric shape of the broken area by a digitized point cloud and nominal geometry. The core software technologies include four aspects: (i) point-to-surface-best-fitting technology that puts the point cloud coordinate system nominal CAD coordinate system, (ii) a procedure to extract a broken boundary that automatically separates the broken area and the unbroken area, (iii) geometric model representation for the broken area, and (iv) generation of a STL file to drive CNC laser machine. The tool has been implemented with UG API. Some experimental results have shown that the presented strategy is efficient for repair automation.
MINIMIZING TOOL CHANGEOVERS IN THREE PARALLEL AND IDENTICAL CNC MACHINING CENTRES
Authors: KUMAR K. D. , KHAN B. KANT
Published: December 2004

This paper considers the problems of scheduling N jobs of the same family, each manufactured in a number of operations, in order, on three CNC machining centres which are equipped with automatic tool changers. A generalized procedure to minimize tool changeovers has been developed and tested on real industrial problems considering a set of possible constraints. The procedure suggested in this paper results in minimal changeovers. Validity of the heuristics suggested is borne out of the fact that when the same case-problem is considered as a Travelling Salesman problem and solved using Hungarian Method, identical result is attained. The procedure is simple and easy to implement in a CNC environment.
EMPIRICAL MODE DECOMPOSITIONS AS DATA-DRIVEN WAVELET-LIKE EXPANSIONS
Authors: FLANDRIN PATRICK , GONÇALVÈS PAULO
Published: December 2004

Huang's data-driven technique of Empirical Mode Decomposition (EMD) is applied to the versatile, broadband, model of fractional Gaussian noise (fGn). The experimental spectral analysis and statistical characterization of the obtained modes reveal an equivalent filter bank structure which shares most properties of a wavelet decomposition in the same context, in terms of self-similarity, quasi-decorrelation and variance progression. Furthermore, the spontaneous adaptation of EMD to "natural" dyadic scales is shown, rationalizing the method as an alternative way for estimating the fGn Hurst exponent.
NEW INSIGHTS INTO THE ESTIMATION OF SCALING EXPONENTS
Authors: LASHERMES B. , ABRY P. , CHAINAIS P.
Published: December 2004

We study the statistical performance of multiresolution-based estimation procedures for the scaling exponents of multifractal processes. These estimators rely on the computation of multiresolution quantities such as wavelet, increment or aggregation coefficients. Estimates are obtained by linear fits performed in log of structure functions of order q versus log of scale plots. Using various and recent types of multiplicative cascades and a large variety of multifractal processes, we study and benchmark, by means of numerical simulations, the statistical performance of these estimation procedures. We show that they all undergo a systematic linearisation effect: for a range of orders q, the estimates account correctly for the scaling exponents; outside that range, the estimates significantly depart from the correct values and systematically behave as linear functions of q. The definition and characterisation of this effect are thoroughly studied. In contradiction with interpretations proposed in the literature, we provide numerical evidence leading to the conclusion that this linearisation effect is neither a finite size effect nor an infiniteness of moments effect, but that its origin should be related to the deep nature of the process itself. We comment on its importance and consequences for the practical analysis of the multifractal properties of empirical data.
ON ADAPTIVE ESTIMATION FOR LOCALLY STATIONARY WAVELET PROCESSES AND ITS APPLICATIONS
Authors: VAN BELLEGEM SÉBASTIEN , VON SACHS RAINER
Published: December 2004

The class of locally stationary wavelet processes is a wavelet-based model for covariance nonstationary zero mean time series. This paper presents an algorithm for the pointwise adaptive estimation of their time-varying spectral density. The performance of the procedure is evaluated on simulated and real time series. Two applications of the procedure are also presented and evaluated on real data. The first is a test of local existence for the coefficients of the so-called wavelet periodogram. The second is a new test of covariance stationarity.
BEAMLAB AND REPRODUCIBLE RESEARCH
Authors: DONOHO DAVID L. , HUO XIAOMING
Published: December 2004

In the first 'Wavelets and Statistics' conference proceedings1, our group published 'Wavelab and Reproducible Research', in which we advocated using the internet for publication of software and data so that research results could be duplicated by others. Much has happened in the last decade that bears on the notion of reproducibility, and we will review our experience. We will also describe a new software package BEAMLAB containing routines for multiscale geometric analysis, and describe some of its capabilities.

BEAMLAB makes available, in one package, all the code to reproduce all the figures in our recently published articles on beamlets, curvelets and ridgelets. The interested reader can inspect the source code to see what algorithms were used, and how parameters were set to produce the figures, and will then be able to modify the source codes to produce variations of our results.

Some new examples of numerical studies based on BEAMLAB are provided here.
MULTIVARIATE SPECTRAL ANALYSIS USING HILBERT WAVELET PAIRS
Authors: WHITCHER BRANDON , CRAIGMILE PETER F.
Published: December 2004

We investigate the use of Hilbert wavelet pairs (HWPs) in the non-decimated discrete wavelet transform for the time-varying spectral analysis of multivariate time series. HWPs consist of two high-pass and two low-pass compactly supported filters, such that one high-pass filter is the Hilbert transform (approximately) of the other. Thus, common quantities in the spectral analysis of time series (e.g., power spectrum, coherence, phase) may be estimated in both time and frequency. Compact support of the wavelet filters ensures that the frequency axis will be partitioned dyadically as with the usual discrete wavelet transform. The proposed methodology is used to analyze a bivariate time series of zonal (u) and meridional (v) winds over Truk Island.
DEGREE OF ENTANGLEMENT FOR QUANTUM STATES
Authors: ZHAO HUI , WANG ZHI-XI
Published: December 2004

A measure to quantify the degree of entanglement for two qubits (2×2) in a pure state is presented in Phys. Rev.A65, 044303 (2002). We generalize their results to 2×n quantum systems. An analytical expression of the entanglement of formation for quantum mixed states of 2×n quantum systems is obtained. Moreover for multipartite quantum systems a generalized "measure" is presented to judge if a pure state is separable or maximally entangled.
EXAMPLES OF NON-UNIFORM LIMITING DISTRIBUTIONS FOR THE QUANTUM WALK ON EVEN CYCLES
Authors: BEDNARSKA MAŁGORZATA , GRUDKA ANDRZEJ , KURZYŃSKI PAWEŁ , ŁUCZAK TOMASZ , WÓJCIK ANTONI
Published: December 2004

We present three different types of the evolution of a time-averaged probability distribution of the quantum walk on even cycles. We concentrate on initial states which lead to non-uniform limiting distributions.
DESTRUCTION OF QUANTUM STATES OVER DISCRETE AND CONTINUOUS VARIABLES
Authors: CABAN PAWEŁ , REMBIELIŃSKI JAKUB , SMOLIŃSKI KORDIAN A. , WALCZAK ZBIGNIEW
Published: December 2004

Prediction of the correlation between the data does not cause any problems in an ideal Einstein–Podolsky–Rosen (EPR) experiment, but if both measurements are not really performed at the same time one should take into account that a particle is irreversibly absorbed by a detector during the measurement. We calculate with full details the destruction of quantum states during the spin measurement of a particle involving localization of a particle in a detector in a system of two distinguishable particles of spin-½ and consider an example of the destruction in the configuration typical for EPR experiments.
THE HSW CHANNEL CAPACITY FOR THE DIAGONAL UNITAL QUDIT CHANNELS
Authors: WU YU-CHUN , ZHOU ZHENG-WEI , GUO GUANG-CAN
Published: December 2004

The Holevo–Schumacher–Westermoreland (HSW) channel capacity for the diagonal unital qudit channels is considered. In Phys. Rev.A69, 022302, the HSW channel capacity for the diagonal unital qudit channels Φ is given as χ(Φ)=1- min ρH(Φ(ρ)), where minimization is over the input states of the channel. In this paper, using the concavity of von Neumann entropy, we show that using only pure states we can work out its HSW channel capacity. Hence, our result simplifies the computation.
A NOTE ON THE LOSS OF COHERENCE IN WAVE PACKETS SQUEEZED SYSTEMS
Authors: LANDOLFI G. , RUGGERI G. , SOLIANI G.
Published: December 2004

Time-dependent dynamical systems with a particular emphasis on models attaining the minimum value of uncertainty formula are considered. The role of the Bogolubov coefficients, in general and in the context of the loss of minimum uncertainty, is analyzed. Different fluctuation values on squeezed states are performed. The decoherence energy is parametrized by an angle ϕ and turns out to vanish whenever ϕ=π. An application to the Paul trap theory is discussed.
Myofibrillar and collagen protein synthesis in human skeletal muscle in young men after maximal shortening and lengthening contractions
Authors: Moore Daniel R. , Phillips Stuart M. , Babraj John A. , Smith Kenneth , Rennie Michael J.
Published: December 2004

We aimed to determine whether there were differences in the extent and time course of skeletal muscle myofibrillar protein synthesis (MPS) and muscle collagen protein synthesis (CPS) in human skeletal muscle in an 8.5-h period after bouts of maximal muscle shortening (SC; average peak torque = 225 ± 7 N·m, means ± SE) or lengthening contractions (LC; average peak torque = 299 ± 18 N·m) with equivalent work performed in each mode. Eight healthy young men (21.9 ± 0.6 yr, body mass index 24.9 ± 1.3 kg/m2) performed 6 sets of 10 maximal unilateral LC of the knee extensors on an isokinetic dynamometer. With the contralateral leg, they then performed 6 sets of maximal unilateral SC with work matched to the total work performed during LC (10.9 ± 0.7 vs. 10.9 ± 0.8 kJ, P = 0.83). After exercise, the participants consumed small intermittent meals to provide 0.1 g·kg−1·h−1 of protein and carbohydrate. Prior exercise elevated MPS above rest in both conditions, but there was a more rapid rise after LC ( P < 0.01). The increases ( P < 0.001) in CPS above rest were identical for both SC and LC and likely represent a remodeling of the myofibrillar basement membrane. Therefore, a more rapid rise in MPS after maximal LC could translate into greater protein accretion and muscle hypertrophy during chronic resistance training utilizing maximal LC.