bluuebunny/crossref_metadata_2025 huggingface dataset:
Shedding Patterns of Verocytotoxin-ProducingEscherichia coliStrains in a Cohort of Calves and Their Dams on a Scottish Beef Farm
Authors: Shaw D. J. , Jenkins C. , Pearce M. C. , Cheasty T. , Gunn G. J. , Dougan G. , Smith H. R. , Woolhouse M. E. J. , Frankel G.
Published: December 2004

Rectal fecal samples were taken once a week from 49 calves on the same farm. In addition, the dams of the calves were sampled at the time of calf birth and at the end of the study. Strains of verocytotoxin-producingEscherichia coli(VTEC) were isolated from these samples by using PCR and DNA probe hybridization tests and were characterized with respect to serotype, verocytotoxin gene (vtx) type, and the presence of the intimin (eae) and hemolysin (ehxA) genes. A total of 170 VTEC strains were isolated during 21 weeks from 130 (20%) of 664 samples from calves and from 40 (47%) of 86 samples from their dams. The characteristics of the calf strains differed from those strains isolated from the dams with respect to verocytotoxin 2 and the presence of theeaegene. In addition, no calf shed the same VTEC serogroup (excluding O?) as its dam at birth or at the end of the study. The most frequently detected serogroups in calves were serogroup O26 and provisional serogroup E40874 (VTEC O26 was found in 25 calves), whereas in dams serogroup O91 and provisional serogroup E54071 were the most common serogroups. VTEC O26 shedding appeared to be associated with very young calves and declined as the calves aged, whereas VTEC O2 shedding was associated with housing of the animals. VTEC O26 strains from calves were characterized by the presence of thevtx1,eae, andehxAgenes, whereasvtx2was associated with VTEC O2 and provisional serogroup E40874. The high prevalence of VTEC O26 and of VTEC strains harboring theeaegene in this calf cohort is notable because of the association of the O26 serogroup and the presence of theeaegene with human disease. No association between calf diarrhea and any of the VTEC serogroups was identified.
Cyclo(l-Leucyl-l-Prolyl) Produced byAchromobacter xylosoxidansInhibits Aflatoxin Production byAspergillus parasiticus
Authors: Yan Pei-Sheng , Song Yuan , Sakuno Emi , Nakajima Hiromitsu , Nakagawa Hiroyuki , Yabe Kimiko
Published: December 2004

Aflatoxins are potent carcinogenic and toxic substances that are produced primarily byAspergillus flavusandAspergillus parasiticus. We found that a bacterium remarkably inhibited production of norsolorinic acid, a precursor of aflatoxin, byA. parasiticus. This bacterium was identified asAchromobacter xylosoxidansbased on its 16S ribosomal DNA sequence and was designatedA. xylosoxidansNFRI-A1.A. xylosoxidansstrains commonly showed similar inhibition. The inhibitory substance(s) was excreted into the medium and was stable after heat, acid, or alkaline treatment. Although the bacterium appeared to produce several inhibitory substances, we finally succeeded in purifying a major inhibitory substance from the culture medium using Diaion HP20 column chromatography, thin-layer chromatography, and high-performance liquid chromatography. The purified inhibitory substance was identified as cyclo(l-leucyl-l-prolyl) based on physicochemical methods. The 50% inhibitory concentration for aflatoxin production byA. parasiticusSYS-4 (= NRRL2999) was 0.20 mg ml−1, as determined by the tip culture method. High concentrations (more than 6.0 mg ml−1) of cyclo(l-leucyl-l-prolyl) further inhibited fungal growth. Similar inhibitory activities were observed with cyclo(d-leucyl-d-prolyl) and cyclo(l-valyl-l-prolyl), whereas cyclo(d-prolyl-l-leucyl) and cyclo(l-prolyl-d-leucyl) showed weaker activities. Reverse transcription-PCR analyses showed that cyclo(l-leucyl-l-prolyl) repressed transcription of the aflatoxin-related genesaflR,hexB,pksL1, anddmtA. This is the first report of a cyclodipeptide that affects aflatoxin production.
Effects of Climate on Incidence of
Campylobacter
spp. in Humans and Prevalence in Broiler Flocks in Denmark
Authors: Patrick Mary Evans , Christiansen Lasse Engbo , Wainø Michael , Ethelberg Steen , Madsen Henrik , Wegener Henrik Caspar
Published: December 2004

Campylobacter
infections are increasing and pose a serious public health problem in Denmark. Infections in humans and broiler flocks show similar seasonality, suggesting that climate may play a role in infection. We examined the effects of temperature, precipitation, relative humidity, and hours of sunlight on
Campylobacter
incidence in humans and broiler flocks by using lag dependence functions, locally fitted linear models, and cross validation methods. For humans, the best model included average temperature and sunlight 4 weeks prior to infection; the maximum temperature lagged at 4 weeks was the best single predictor. For broilers, the average and maximum temperatures 3 weeks prior to slaughter gave the best estimate; the average temperature lagged at 3 weeks was the best single predictor. The combined effects of temperature and sunlight or the combined effects of temperature and relative humidity predicted the incidence in humans equally well. For broiler flock incidence these factors explained considerably less. Future research should focus on elements within the broiler environment that may be affected by climate, as well as the interaction of microclimatic factors on and around broiler farms. There is a need to quantify the contribution of broilers as a source of campylobacteriosis in humans and to further examine the effect of temperature on human incidence after this contribution is accounted for. Investigations should be conducted into food consumption and preparation practices and poultry sales that may vary by season.
Novel, Attached, Sulfur-Oxidizing Bacteria at Shallow Hydrothermal Vents Possess Vacuoles Not Involved in Respiratory Nitrate Accumulation
Authors: Kalanetra Karen M. , Huston Sherry L. , Nelson Douglas C.
Published: December 2004

Novel, vacuolate sulfur bacteria occur at shallow hydrothermal vents near White Point, Calif. There, these filaments are attached densely to diverse biotic and abiotic substrates and extend one to several centimeters into the surrounding environment, where they are alternately exposed to sulfidic and oxygenated seawater. Characterizations of native filaments collected from this location indicate that these filaments possess novel morphological and physiological properties compared to all other vacuolate bacteria characterized to date. Attached filaments, ranging in diameter from 4 to 100 μm or more, were composed of cylindrical cells, each containing a thin annulus of sulfur globule-filled cytoplasm surrounding a large central vacuole. A near-complete 16S rRNA gene sequence was obtained and confirmed by fluorescent in situ hybridization to be associated only with filaments having a diameter of 10 μm or more. Phylogenetic analysis indicates that these wider, attached filaments form within the gamma proteobacteria a monophyletic group that includes all previously described vacuolate sulfur bacteria (the genera
Beggiatoa
,
Thioploca
, and
Thiomargarita
) and no nonvacuolate genera. However, unlike for all previously described vacuolate bacteria, repeated measurements of cell lysates from samples collected over 2 years indicate that the attached White Point filaments do not store internal nitrate. It is possible that these vacuoles are involved in transient storage of oxygen or contribute to the relative buoyancy of these filaments.
Isolation and Characterization of Novel Marine-Derived Actinomycete Taxa Rich in Bioactive Metabolites
Authors: Magarvey Nathan A. , Keller Jessica M. , Bernan Valerie , Dworkin Martin , Sherman David H.
Published: December 2004

A unique selective enrichment procedure has resulted in the isolation and identification of two new genera of marine-derived actinobacteria. Approximately 90% of the microorganisms cultured by using the presented method were from the prospective new genera, a result indicative of its high selectivity. In this study, 102 actinomycetes were isolated from subtidal marine sediments collected from the Bismarck Sea and the Solomon Sea off the coast of Papua New Guinea. A combination of physiological parameters, chemotaxonomic characteristics, distinguishing 16S rRNA gene sequences, and phylogenetic analysis based on 16S rRNA genes provided strong evidence for the two new genera (represented by strains of the PNG1 clade and strain UMM518) within the family
Micromonosporaceae
. Biological activity testing of fermentation products from the new marine-derived actinomycetes revealed that several had activities against multidrug-resistant gram-positive pathogens, malignant cells, and vaccinia virus replication.
Analysis of Proteasome-Dependent Proteolysis in
Haloferax volcanii
Cells, Using Short-Lived Green Fluorescent Proteins
Authors: Reuter Christopher J. , Maupin-Furlow Julie A.
Published: December 2004

Proteasomes are energy-dependent proteases that are central to the quality control and regulated turnover of proteins in eukaryotic cells. Dissection of this proteolytic pathway in archaea, however, has been hampered by the lack of substrates that are easily detected in whole cells. In the present study, we developed a convenient reporter system by functional expression of a green fluorescent protein variant with C-terminal fusions in the haloarchaeon
Haloferax volcanii
. The levels of this reporter protein correlated with whole-cell fluorescence that was readily detected in culture. Accumulation of the reporter protein was dependent on the sequence of the C-terminal amino acid fusion, as well as the presence of an irreversible, proteasome-specific inhibitor (
clasto
-lactacystin β-lactone). This inhibitor was highly specific for
H. volcanii
20S proteasomes, with a

K
i

of ∼40 nM. In contrast, phenylmethanesulfonyl fluoride did not influence the levels of fluorescent reporter protein or inhibit 20S proteasomes. Together, these findings provide a powerful tool for the elucidation of protein substrate recognition motifs and the identification of new genes which may be involved in the proteasome pathway of archaea.
Nucleotide Sequences, Genetic Organization, and Distribution of pEU30 and pEL60 from
Erwinia amylovora
Authors: Foster Gayle C. , McGhee Gayle C. , Jones Alan L. , Sundin George W.
Published: December 2004

The nucleotide sequences, genetic organization, and distribution of plasmids pEU30 (30,314 bp) and pEL60 (60,145 bp) from the plant pathogen
Erwinia amylovora
are described. The newly characterized pEU30 and pEL60 plasmids inhabited strains isolated in the western United States and Lebanon, respectively. The gene content of pEU30 resembled plasmids found in plant-associated bacteria, while that of pEL60 was most similar to IncL/M plasmids inhabiting enteric bacteria.
Reevaluation and Reduction of a PCR Bias Caused by Reannealing of Templates
Authors: Kurata Shinya , Kanagawa Takahiro , Magariyama Yukio , Takatsu Kyoko , Yamada Kazutaka , Yokomaku Toyokazu , Kamagata Yoichi
Published: December 2004

We reevaluated the bias toward a 1:1 ratio of products in multitemplate PCR used in ecological studies and showed that the template reannealing at the annealing step would not cause the bias; however, the preferential homoduplex formation during temperature decrease from denaturation to annealing step would cause the bias.
Role for Compatible Solutes Glycine Betaine and
l
-Carnitine in Listerial Barotolerance
Authors: Smiddy Mary , Sleator Roy D. , Patterson Margaret F. , Hill Colin , Kelly Alan L.
Published: December 2004

Increased listerial barotolerance at elevated osmolarity is attributed, in part, to the presence of accumulated betaine and
l
-carnitine. The percentage of listerial survival following exposure to 400 MPa for 5 min increased from 0.008 to 0.02% with added
l
-carnitine (5 mM) and to 0.05% with added betaine (5 mM). Furthermore, listerial cells incapable of transporting compatible solutes fail to adapt to high pressure at elevated osmolarity.
Resistance of Solid-Phase U(VI) to Microbial Reduction during In Situ Bioremediation of Uranium-Contaminated Groundwater
Authors: Ortiz-Bernad Irene , Anderson Robert T. , Vrionis Helen A. , Lovley Derek R.
Published: December 2004

Speciation of solid-phase uranium in uranium-contaminated subsurface sediments undergoing uranium bioremediation demonstrated that although microbial reduction of soluble U(VI) readily immobilized uranium as U(IV), a substantial portion of the U(VI) in the aquifer was strongly associated with the sediments and was not microbially reducible. These results have important implications for in situ uranium bioremediation strategies.
Effects of Expression of
hemA
and
hemB
Genes on Production of Porphyrin in
Propionibacterium freudenreichii
Authors: Piao Yongzhe , Kiatpapan Pornpimon , Yamashita Mitsuo , Murooka Yoshikatsu
Published: December 2004

The genus
Propionibacterium
has a wide range of probiotic activities that are exploited in dairy and fermentation systems such as cheeses, propionic acid, and tetrapyrrole compounds. In order to improve production of tetrapyrrole compounds, we expressed the
hemA
gene, which encodes δ-aminolevulinic acid (ALA) synthase from
Rhodobacter sphaeroides
, and the
hemB
gene, which encodes porphobilinogen (PBG) synthase from
Propionibacterium freudenreichii
subsp.
shermanii
IFO12424, either monocistronically or polycistronically in strain IFO12426. The recombinant strains accumulated larger amounts of ALA and PBG, with resultant 28- to 33-fold-higher production of porphyrinogens, such as uroporphyrinogen and coproporphyrinogen, than those observed in strain IFO12426, which harbored the shuttle vector pPK705.
Doctors’ views about the importance of shared values in HIV positive patient care: a qualitative study
Authors: Lawlor A , Braunack-Mayer A
Published: December 2004

Robert Veatch has proposed a model of the doctor-patient relationship that has as its foundation the sharing of values between the doctor and the patient. This paper uses qualitative research conducted with six doctors involved in the long term, specialised care of HIV positive patients in South Australia to explore the practical application of Veatch’s value sharing model in that setting. The research found that the doctors in this study linked “values” with sexual identity such that they defined value sharing, in part, as a shared set of values and beliefs about sexual identity and practices. They voluntarily identified themselves as either homosexual or heterosexual and they regarded the relation between their own sexual identity and that of their patients as important for the provision of quality care. None of the doctors thought that value sharing, in the way they defined it, wasessentialto the clinical relationship, but the homosexual doctors attributed a greater degree of importance to it than their heterosexual colleagues.
Genes and equality: Figure 1
Authors: Farrelly C
Published: December 2004

The way people think about equality as a value will influence how they think genetic interventions should be regulated. In this paper the author uses the taxonomy of equality put forth by Derek Parfit and applies this to the issue of genetic interventions. It is argued that telic egalitarianism is untenable and that deontic egalitarianism collapses into prioritarianism. The priority view maintains that it is morally more important to benefit the people who are worse off. Once this precision has been given to the concerns egalitarians have, a number of diverse issues must be considered before determining what the just regulation of genetic interventions would be. Consideration must be given to the current situation of the least advantaged, the fiscal realities behind genetic interventions, the budget constraints on other social programmes egalitarians believe should receive scarce public funds, and the interconnected nature of genetic information. These considerations might lead egalitarians to abandon what they take to be the obvious policy recommendations for them to endorse regarding the regulation of gene therapies and enhancements.
Surveys on attitudes towards legalisation of euthanasia: importance of question phrasing
Authors: Hagelin J , Nilstun T , Hau J , Carlsson H-E
Published: December 2004

Aim:To explore whether the phrasing of the questions and the response alternatives would influence the answers to questions about legalisation of euthanasia.

Methods:Results were compared from two different surveys in populations with similar characteristics. The alternatives “positive”, “negative”, and “don’t know” (first questionnaire) were replaced with an explanatory text, “no legal sanction”, four types of legal sanctions, and no possibility to answer “don’t know” (second questionnaire). Four undergraduate student groups (engineering, law, medicine, and nursing) answered.

Results:In the first questionnaire (n = 684) 43% accepted euthanasia (range 28–50%), 14% (8–33%) did not, and 43% (39–59%) answered “don’t know”. Two per cent of the respondents declined to answer. In comparison with previous surveys on attitudes to euthanasia the proportion of “don’t know” was large. The results of the second questionnaire (n = 639), showed that 38% favoured “no legal prosecution” (26–50%). However, 62% (50–74%) opted for different kinds of legal sanctions, and two of four groups expressed significantly different views in the two surveys. A proportion of 10% declined to answer the second questionnaire.

Conclusion:An introduction of an explanatory text and a wider range of response alternatives produced differences between the results of the two surveys conducted.
The ethics of the placebo in clinical practice
Authors: Lichtenberg P , Heresco-Levy U , Nitzan U
Published: December 2004

While discussions of the ethics of the placebo have usually dealt with their use in a research context, the authors address here the question of the placebo in clinical practice. It is argued, firstly, that the placebo can be an effective treatment. Secondly, it is demonstrated that its use does not always entail deception. Finally guidelines are presented according to which the placebo may be used for clinical purposes. It is suggested that in select cases, use of the placebo may even be morally imperative. The argument is illustrated by three case vignettes.
The person, the soul, and genetic engineering
Authors: Polkinghorne J C
Published: December 2004

Argument about the ethical possibility of the therapeutic use of embryonic stem cells depends critically on the evaluation of the moral status of the very early embryo. Some assert that at the blastocyst stage it is only potentially human, not yet possessing the full ethical status of personhood, while others assert that from its formation the embryo possesses all the moral rights of a human person. It is shown that a decision on this issue is closely related to how human nature is to be understood. The idea of a person as a dual combination of body and spirit correlates naturally with the assertion of absolute personhood from conception, while an idea of human psychosomatic unity encourages a development picture in which the embryo only grows gradually into personhood. The latter view is seen to be encouraged by new advances in science which emphasise the importance of the concept of information in the discussion of complex systems. Other ethical issues related to human genetics are also briefly reviewed.
Cell phoney: human cloning afterQuintavalle
Authors: Morgan Derek , Ford Mary
Published: December 2004

Reproductive cloning has thrown up new scientific possibilities, ethical conundrums, and legal challenges. An initial question, considered by the English courts in 2003, was whether the technique presently available, that of cell nucleus replacement, falls outside the provisions of theHuman Fertilisation and Embryology Act1990. If it does, the creation and use, including use in research protocols, of human embryos would be unregulated, disclosing a need to consider remedial legislation. The resolution by the courts of this legal question dramatically engages them in a resolution of fundamental ethical dilemmas, and discloses the possibilities and limitation of negotiating science policy through the processes of litigation.
Attitudes of healthcare professionals and parents regarding genetic testing for violent traits in childhood
Authors: Campbell E , Ross L F
Published: December 2004

Objectives:Although no genetic tests for violent behaviour are currently available, research is ongoing to isolate genes related to a propensity for violence. We explored the attitudes of parents and healthcare professionals toward behavioural genetic testing for violence.

Design:The attitudes of healthcare professionals and the lay public about genetic testing of children were elicited for a range of conditions through interviews with healthcare professionals and focus groups with parents. All participants were informed that behavioural genetic testing was the only hypothetical genetic test in our script and it was presented as the last condition.

Participants:The healthcare professionals included both genetic professionals and paediatricians. Focus group participants were recruited through various community institutions in the southside of Chicago and nearby suburbs.

Results:The healthcare professionals tended to medicalise behavioural genetics, and were opposed to testing unless treatment was available. They were also uniformly concerned about the potential harms of this information, including unintentional adverse effects from environmental changes. In contrast, parents wanted genetic testing for behavioural traits to be available even in the absence of proved medical treatments. Not all parents wanted to test their own children, and some parents were concerned about self-fulfilling prophecies. Some parents, however, felt the information was important for their understanding, and could be used to support environmental changes.

Conclusions:While healthcare professionals medicalised behavioural genetics, parents focused on environmental causes and influences. Consequently, healthcare professionals do not want to offer testing if there is no clear treatment, while parents may want this information to shape environmental influences.
Rights of patients in developing countries: the case of Turkey
Authors: Aydin E
Published: December 2004

Patient rights are universal values which we have to adopt. It is not so easy, however, to put such values and principles into effect. As approaches and attitudes differ from individual to individual, from society to society, and from country to country, a uniform application of these values is difficult. If we want to reach a general conclusion about the status of patient rights in the world as whole, we should examine the situation in individual countries. As far as Turkey is concerned, we can say that, although the idea of patient rights is accepted in principle, patient rights have yet to be adequately implemented.
THE ELECTRIC AND MAGNETIC BEHAVIOR OF THE EuBa2(Cu1-xGax)3O7-d COMPOUNDS COMPARED WITH Eu1-xGaxBa2Cu3O7-d
Authors: REDAC TEODOR-RADU
Published: December 2004

The paper presents experimental electrical and magnetic data concerning the EuBa 2( Cu 1-x Ga x)3 O 7-d and Eu 1-x Ga x Ba 2 Cu 3 O 7-d compounds. We emphasized the effect of the substitution of copper and europium for gallium, as well as the effect of the thermal treatment on the compound.
REMARKS ON PAPAPETROU CLASS OF VACUUM SOLUTIONS OF EINSTEIN EQUATIONS
Authors: KHUGAEV A. V. , AHMEDOV B. J.
Published: December 2004

Class of axially symmetric solutions of vacuum Einstein field equations including the Papapetrou solution as particular case has been found. It has been shown that the derived solution describes the external axial symmetric gravitational field of the source with nonvanishing mass. The general solution is obtained for this class of functions. As an example of physical application, the spacetime metric outside a line gravitomagnetic monopole has been obtained from Papapetrou solution of vacuum equations of gravitational field.
GENERALIZED UNCERTAINTY PRINCIPLE AND THE QUANTUM ENTROPY OF A KERR BLACK HOLE
Authors: LI CHEN , XIANG LI , SHEN YOU-GEN
Published: December 2004

Taking into account the generalized uncertainty principle (GUP), we calculate the entropy of a scalar field in a Kerr spacetime. Different to previous work, we have used an new equation of the density of quantum states, which arises from the modified commutation relation [Formula: see text]. The divergence in the brick wall model is removed, without the cutoff.
LINEAR FORM OF 3-SCALE SPECIAL RELATIVITY ALGEBRA AND THE RELEVANCE OF STABILITY
Authors: CHRYSSOMALAKOS C. , OKON E.
Published: December 2004

We show that the algebra of the recently proposed Triply Special Relativity can be brought to a linear (i.e., Lie) form by a correct identification of its generators. The resulting Lie algebra is the stable form proposed by Vilela Mendes a decade ago, itself a reapparition, up to some important sign, of Yang's algebra, dating from 1947. As a corollary we assure that, within the Lie algebra framework, there is no Quadruply Special Relativity.
P-STARS
Authors: CEA PAOLO
Published: December 2004

P-Stars are a new class of compact stars made of up and down quarks in β-equilibrium with electrons in an Abelian chromomagnetic condensate. We show that P-Stars are able to account for compact stars with R≲6 Km , as well as stars with radius comparable with canonical Neutron Stars. We find that cooling curves of P-Stars compare rather well with observational data. We suggest that P-Matter produced at the primordial deconfinement transition is a viable candidate for baryonic Cold Dark Matter. Finally, we show that P-Stars are able to overcome the gravitational collapse even for masses much greater than 106 M⊙.
THE VIRGO ALIGNMENT PUZZLE IN PROPAGATION OF RADIATION ON COSMOLOGICAL SCALES
Authors: RALSTON JOHN P. , JAIN PANKAJ
Published: December 2004

We reconsider analysis of data on the cosmic microwave background on the largest angular scales. Temperature multipoles of any order factor naturally into a direct product of axial quantities and cosets. Striking coincidences exist among the axes associated with the dipole, quadrupole, and octupole CMB moments. These axes also coincide well with two other axes independently determined from polarizations at radio and optical frequencies propagating on cosmological scales. The five coincident axes indicate physical correlation and anisotropic properties of the cosmic medium not predicted by the conventional Big Bang scenario. We consider various mechanisms, including foreground corrections, as candidates for the observed correlations. We also consider whether the propagation anomalies may be a signal of "dark energy" in the form of a condensed background field. Perhaps light propagation will prove to be an effective way to look for the effects of dark energy.
MICROLENSING SIGNATURE OF A WHITE DWARF POPULATION IN THE GALACTIC HALO
Authors: HAFIZI M. , DE PAOLIS F. , INGROSSO G. , NUCITA A. A.
Published: December 2004

Microlensing and pixel-lensing surveys play a fundamental role in the searches for galactic dark matter and in the study of the galactic structure. Recent observations suggest the presence of a population of old white dwarfs with high proper motion, probably in the galactic halo, with local mass density in the range 1.3×10-4-4.4×10-3 M⊙ pc -3, in addition to the standard galactic stellar disk and dark halo components. Investigation of the signatures on microlensing results towards the LMC of these different lens populations, with particular emphasis to white dwarfs, is the main purpose of the present paper. This is done by evaluating optical depth and microlensing rate of the various lens populations and then calculating through a Monte Carlo program, the probability that a lens which has caused a microlensing event of duration t E belongs to a certain galactic population. Data obtained by the MACHO Collaboration allow us to set an upper bound of 1.6×10-3 M⊙ pc -3 to the local mass density of white dwarfs distributed in spheroidal models, while for white dwarfs in disk models all values for the local mass density are in agreement with observational results.
ON A STOCHASTIC CAPTURE–RECAPTURE PREDATOR–PREY MODEL
Authors: AGGOUN LAKHDAR
Published: December 2004

A stochastic version of the classical Lotka–Volterra predator–prey model is considered. Using hidden Markov models techniques, we derive a Zakai equation driven by Poisson martingales related to the distribution of the number of individuals in a two-species (predator–prey) animal population. Partial information is provided by a continuous-time version of the so-called capture–recapture sampling technique. By using a gauge transformation a stochastic differential equation is transformed into a linear ordinary differential equations.
A NOVEL INTEGRATED SYSTEM FOR RAPID PRODUCT DEVELOPMENT
Authors: LAN HONGBO , DING YUCHENG , HONG JUN , WU DIANLIANG
Published: December 2004

This paper presents a novel integrated system of rapid product development for reducing the time and cost of product development. The system is composed of four building blocks — digital prototype, virtual prototype, physical prototype and rapid tooling manufacturing system. It can aid effectively in product design, analysis, prototype, mould, and manufacturing process development by integrating closely the various advanced manufacturing technologies which involve the 3D CAD, CAE, reverse engineering, rapid prototyping and rapid tooling. Furthermore, two actual examples are provided to illustrate the application of this integrated system. The results indicate that the system has a high potential to reduce further the cycle and cost of product development.
ALGORITHMIC COOLING OF SPINS: A PRACTICABLE METHOD FOR INCREASING POLARIZATION
Authors: FERNANDEZ JOSÉ M. , LLOYD SETH , MOR TAL , ROYCHOWDHURY VWANI
Published: December 2004

An efficient technique to generate ensembles of spins that are highly polarized by external magnetic fields is the Holy Grail in Nuclear Magnetic Resonance (NMR) spectroscopy. Since spin-half nuclei have steady-state polarization biases that increase inversely with temperature, spins exhibiting high polarization biases are considered cool, even when their environment is warm. Existing spin-cooling techniques are highly limited in their efficiency and usefulness. Algorithmic cooling is a promising new spin-cooling approach that employs data compression methods in open systems. It reduces the entropy of spins on long molecules to a point far beyond Shannon's bound on reversible entropy manipulations, thus increasing their polarization. Here we present an efficient and experimentally feasible algorithmic cooling technique that cools spins to very low temperatures even on short molecules. This practicable algorithmic cooling could lead to breakthroughs in high-sensitivity NMR spectroscopy in the near future, and to the development of scalable NMR quantum computers in the far future. Moreover, while the cooling algorithm itself is classical, it uses quantum gates in its implementation, thus representing the first short-term application of quantum computing devices.
ON THE ADIABATIC QUANTUM EVOLUTION OF A SINGLE QUBIT
Authors: ANDRECUT M. , ALI M. K.
Published: December 2004

The adiabatic quantum evolution method has generally been studied for the case where the linear interpolation from an initial to a final Hamiltonian is taken. However, this approach fails even for the case of a single qubit, when the initial and final states are orthogonal or almost orthogonal. In this case, the evolution time becomes infinite. We show that by using a simple nonlinear interpolation method the adiabatic evolution can be done in finite time, regardless of the orthogonality of the initial and final states.
BEST SEPARABLE APPROXIMATION WITH SEMI-DEFINITE PROGRAMMING METHOD
Authors: JAFARIZADEH M. A. , MIRZAEE M. , REZAEE M.
Published: December 2004

The present methods for obtaining the optimal Lewenestein–Sanpera decomposition of a mixed state are difficult to handle analytically. We provide a simple analytical expression for the optimal Lewenstein–Sanpera decomposition by using semi-definite programming. In particular, we obtain the optimal Lewenstein–Sanpera decomposition for some examples such as: the Bell decomposable state, the iso-concurrence state, the generic two-qubit state in the Wootters basis, the 2⊗3 Bell decomposable state, the d⊗d Werner and isotropic states, a one parameter 3⊗3 state, and finally a multi-partite isotropic state.
1,25(OH)2D3 acts as a bone-forming agent in the hormone-independent senescence-accelerated mouse (SAM-P/6)
Authors: Duque Gustavo , Macoritto Michael , Dion Natalie , Ste-Marie Louis-Georges , Kremer Richard
Published: December 2004

Recent studies suggest that vitamin D signaling regulates bone formation. However, the overall effect of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on bone turnover in vivo is still unclear. In this study, our aim was to examine the effect of 1,25(OH)2D3 on bone turnover in SAM-P/6, a hormone-independent mouse model of senile osteoporosis characterized by a decrease in bone formation. Male and female 4-mo-old SAM-P/6 mice were treated with 1,25(OH)2D3 (18 pmol/24 h) or vehicle for a period of 6 wk, and a group of age- and sex-matched nonosteoporotic animals was used as control. Bone mineral density (BMD) at the lumbar spine increased rapidly by >30 ± 5% ( P < 0.001) in 1,25(OH)2D3-treated SAM-P/6 animals, whereas BMD decreased significantly by 18 ± 2% ( P < 0.01) in vehicle-treated SAM-P/6 animals and remained stable in control animals during the same period. Static and dynamic bone histomorphometry indicated that 1,25(OH)2D3 significantly increased bone volume and other parameters of bone quality as well as subperiosteal bone formation rate compared with vehicle-treated SAM-P/6 mice. However, no effect on trabecular bone formation was observed. This was accompanied by a marked decrease in the number of osteoclasts and eroded surfaces. A significant increase in circulating bone formation markers and a decrease in bone resorption markers was also observed. Finally, bone marrow cells, obtained from 1,25(OH)2D3-treated animals and cultured in the absence of 1,25(OH)2D3, differentiated more intensely into osteoblasts compared with those derived from vehicle-treated mice cultured in the same conditions. Taken together, these findings demonstrate that 1,25(OH)2D3 acts simultaneously on bone formation and resorption to prevent the development of senile osteoporosis.
Age diminishes the testicular steroidogenic response to repeated intravenous pulses of recombinant human LH during acute GnRH-receptor blockade in healthy men
Authors: Veldhuis Johannes D. , Veldhuis Nathan J. D. , Keenan Daniel M. , Iranmanesh Ali
Published: December 2004

Testosterone (Te) concentrations fall gradually in healthy aging men. Postulated mechanisms include relative failure of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), and/or gonadal Te secretion. Available methods to test Leydig cell Te production include pharmacological stimulation with human chorionic gonadotropin (hCG). We reasoned that physiological lutropic signaling could be mimicked by pulsatile infusion of recombinant human (rh) LH during acute suppression of LH secretion. To this end, we studied eight young (ages 19–30 yr) and seven older (ages 61–73 yr) men in an experimental paradigm comprising 1) inhibition of overnight LH secretion with a potent selective GnRH-receptor antagonist (ganirelix, 2 mg sc), 2) intravenous infusion of consecutive pulses of rh LH (50 IU every 2 h), and 3) chemiluminometric assay of LH and Te concentrations sampled every 10 min for 26 h. Statistical analyses revealed that 1) ganirelix suppressed LH and Te equally (> 75% median inhibition) in young and older men, 2) infused LH pulse profiles did not differ by age, and 3) successive intravenous pulses of rh LH increased concentrations of free Te (ng/dl) to 4.6 ± 0.38 (young) and 2.1 ± 0.14 (older; P < 0.001) and bioavailable Te (ng/dl) to 337 ± 20 (young) and 209 ± 16 (older; P = 0.002). Thus controlled pulsatile rh LH drive that emulates physiological LH pulses unmasks significant impairment of short-term Leydig cell steroidogenesis in aging men. Whether more prolonged pulsatile LH stimulation would normalize this inferred defect is unknown.
Lithium activates the Wnt and phosphatidylinositol 3-kinase Akt signaling pathways to promote cell survival in the absence of soluble survival factors
Authors: Sinha Diviya , Wang Zhiyong , Ruchalski Kathleen L. , Levine Jerrold S. , Krishnan Selvi , Lieberthal Wilfred , Schwartz John H. , Borkan Steven C.
Published: December 2004

Mouse proximal tubular cells (BUMPT), when cultured in the absence of growth factors, activate a default apoptotic pathway. Although Wnt signaling antagonizes the effect of proapoptotic triggers, its role in regulating the default pathway of apoptosis is less well defined. The present study examines the hypothesis that lithium (Li+) and (2′Z,3′E)-6-bromoindirubin-3′-oxime (BIO), two glycogen synthase kinase-3β (GSK3β) inhibitors, promote survival of growth factor-deprived renal epithelial cells by activating the Wnt pathway. These studies demonstrate that Li+and BIO activate Wnt signaling as indicated by the following changes: phosphorylation (inhibition) of GSK3β; decreased phosphorylation of β-catenin (a GSK3β substrate); nuclear translocation of β-catenin; specific transcriptional activation of Tcf/catenin-responsive pTopflash constructs; and an increase in the expression of cyclin D1 (indicative of a promitogenic cell response). In addition, Li+or BIO significantly increases the phosphorylation (activation) of Akt, an anti-apoptotic protein, and inhibits apoptosis (decreases both annexin-V staining and caspase-3 activation), during serum deprivation. Inhibition of phosphatidylinositol 3-kinase (responsible for Akt activation) either by wortmanin or LY-294002 prevented Li+- or BIO-induced Akt phosphorylation and reduces cell survival without altering the phosphorylation state of GSK3β. Li+or BIO also increases the expression of insulin-like growth factor-II (IGF-II), a potent proliferative signaling protein. Li+or BIO-free conditioned medium harvested from Li+- or BIO-exposed cells also induced Akt phosphorylation, mimicking the protective effect of the two GSK3β inhibitors on serum-starved cells. Furthermore, the effect of conditioned medium on Akt phosphorylation could be inhibited by either LY-294002 or IGF-binding protein. BIO, a specific GSK3β inhibitor, replicated the protective effect of Li+on cell viability, suggesting that GSK3β activation is important for initiating the apoptotic pathway. Taken together, these data suggest that Li+or BIO promotes renal epithelial cell survival by inhibiting apoptosis through GSK3β-dependent activation of the Wnt pathway and subsequent release of IGF-II. Extracellular IGF-II serves as an autocrine survival factor that is responsible, in part, for activating the anti-apoptotic phosphatidylinositol-3-kinase-Akt pathway during serum deprivation.
Src family kinase involvement in rat preglomerular microvascular contractile and [Ca2+]iresponses to ANG II
Authors: Che Qi , Carmines Pamela K.
Published: December 2004

Experiments were performed to investigate the potential role of Src family kinase(s) in the rat afferent arteriolar contractile response to ANG II. The in vitro blood-perfused juxtamedullary nephron technique was employed to monitor afferent arteriolar lumen diameter responses to 1–100 nM ANG II before and during Src family kinase inhibition (10 μM PP2). PP2 did not alter baseline diameter but attenuated ANG II-induced contractile responses by 33 ± 6%. An inactive analog of PP2 (PP3) had no effect on ANG II-induced afferent arteriolar contraction. The effect of Src kinase inhibition on ANG II-induced intracellular free Ca2+concentration ([Ca2+]i) responses was probed in fura 2-loaded preglomerular microvascular smooth muscle cells (PVSMCs) obtained from explants and studied after 3–5 days in culture. In untreated PVSMCs, ANG II evoked peak (Δ = 293 ± 66 nM) and plateau (Δ = 23 ± 8 nM) increases in [Ca2+]i. In PVSMCs pretreated with PP2, baseline [Ca2+]iwas unaltered, but both the peak (Δ = 140 ± 22 nM) and plateau (Δ = 3 ± 2 nM) phases of the ANG II response were significantly reduced compared with untreated cells. PP3 did not alter [Ca2+]iresponses to ANG II. Immunoprecipitation and Western blot analysis confirmed that 100 nM ANG II increased phosphorylation of c-Src (at Y416) in PVSMCs. The phosphorylation response was maximal 1 min after ANG II exposure and was prevented by PP2. We conclude that the preglomerular vasoconstriction evoked by ANG II involves rapid c-Src activation with subsequent effects that contribute to the [Ca2+]iresponse to the peptide.
Time Course of Changes in Brain Activity and Functional Connectivity Associated With Long-Term Adaptation to a Rotational Transformation
Authors: Della-Maggiore Valeria , McIntosh Anthony R.
Published: December 2004

The purpose of this study was to examine the time course of changes in cerebral activity and functional connectivity during long-term adaptation to a visuomotor transformation. Positron emission tomography was used to measure changes in brain activity as subjects tracked a target under the influence of a rotational transformation that distorted visual feedback. The experiment was 1 week long and consisted of two scanning sessions (obtained on days 2 and 7), aimed at examining early and late stages of learning. On average, visuomotor adaptation was achieved within 3 days. During early stages of adaptation, better performance was associated with greater activity in brain areas related to attention including bilateral dorso- and ventrolateral prefrontal cortices, frontal eye fields, and the human homologue of area MT. However, as adaptation proceeded, improvements in performance were associated with greater activity in motor regions such as the left (contralateral) sensorimotor cortex, bilateral anterior cerebellum, left cingulate motor area, right putamen, and a nonmotor region within the middle temporal gyrus. This learning-specific shift in brain activity was associated with a progressive change in the functional connectivity of these regions toward the end of the first session. Interestingly, only the functional connections between the anterior cerebellum, left middle temporal gyrus, and left sensorimotor cortex remained strong once visuomotor adaptation was achieved. Our findings suggest that visuomotor adaptation is not only reflected in persistent changes in activity in motor-related regions, but also in the strengthening and maintenance of specific functional connections.
7 to 12 Hz Activity in Rat Gustatory Cortex Reflects Disengagement From a Fluid Self-Administration Task
Authors: Fontanini Alfredo , Katz Donald B.
Published: December 2004

The 7 to 12 Hz rhythm is a high-voltage oscillatory phenomenon recorded in many rat neocortical regions, largely analogous to the rodent and human somatosensory μ rhythm. Central to any interpretation of the functional significance of this pattern is the analysis of the behavioral context associated with it. Much of the debate on the function of μ, variously believed to represent either an environment-oriented or -isolated state, has relied primarily on its association with quiet immobility. In this report, we describe the relationship between the 7 to 12 Hz rhythm and a more complex behavioral setting, in which we were able to dissociated task orientation from disengagement. We trained head-restrained, water-restricted rats to perform a simple variant of a timed fluid self-administration task, while recording local field potentials from gustatory cortex (GC). Rats progressed through two behavioral states that were clearly distinguishable on the basis of lever-pressing regimes: a task-oriented state and a second state that reflected disengagement from the task. Concurrent GC neural recordings revealed bilaterally coherent oscillations in the 7 to 12 Hz range associated solely with the latter state. Consistent with published recordings of μ rhythm from somatosensory cortex, these rhythmic episodes were endogenously quenched when the rats prepared to lever-press; this inhibition of rhythmic episodes lasted through fluid delivery and consumption, making it clear that GC rhythms are not related to gustatory processing itself. By showing a direct relationship between the 7 to 12 Hz rhythm and disengagement from a task, these data provide strong and novel evidence that this gustatory rhythm in rats is associated with withdrawal from experimental contingencies.
Effect of Light on Anthocyanin Levels in Submerged, Harvested Cranberry Fruit
Authors: Zhou Yu , Singh Bal Ram
Published: December 2004

Anthocyanins are a group of plant antioxidants known for their therapeutic use. The effects of natural light, red light, and far‐red light on individual as well as total anthocyanin content in cranberry fruit (Vaccinium macrocarpon Ait) were examined in an experimental setting designed to mimic water‐harvesting conditions. The reversed‐phase high performance liquid chromatography (HPLC) method was used to separate and analyze the anthocyanins. In contrast to the case of the control sample that was kept in the dark, natural light increased the total anthocyanin level by 75.3% and 87.2% after 24 and 48 hours water immersion, respectively. Red light and far‐red light increased the total anthocyanin level by 41.5% and 34.7%, respectively. The amount of each individual anthocyanin increased differently under natural light, red light, and far‐red light, suggesting that expressions of enzymes that catalyze the anthocyanin biosynthesis are regulated differently by environments.
Molecular Mechanisms Behind the Chemopreventive Effects of Anthocyanidins
Authors: Hou De-Xing , Fujii Makoto , Terahara Norihiko , Yoshimoto Makoto
Published: December 2004

Anthocyanins are polyphenolic ring‐based flavonoids, and are widespread in fruits and vegetables of red‐blue color. Epidemiological investigations and animal experiments have indicated that anthocyanins may contribute to cancer chemoprevention. The studies on the mechanism have been done recently at molecular level. This review summarizes current molecular bases for anthocyanidins on several key steps involved in cancer chemoprevention: (i) inhibition of anthocyanidins in cell transformation through targeting mitogen‐activated protein kinase (MAPK) pathway and activator protein 1 (AP‐1) factor; (ii) suppression of anthocyanidins in inflammation and carcinogenesis through targeting nuclear factor kappa B (NF‐κB) pathway and cyclooxygenase 2 (COX‐2) gene; (iii) apoptotic induction of cancer cells by anthocyanidins through reactive oxygen species (ROS) / c‐Jun NH 2‐terminal kinase (JNK)‐mediated caspase activation. These data provide a first molecular view of anthocyanidins contributing to cancer chemoprevention.
Bioavailability and Biokinetics of Anthocyanins From Red Grape Juice and Red Wine
Authors: Bitsch Roland , Netzel Michael , Frank Thomas , Strass Gabriele , Bitsch Irmgard
Published: December 2004

In a comparative study, 9 healthy volunteers ingested a single oral dose of 400 mL red grape juice or red wine with dose‐adjusted anthocyanin content (283.5 mg or 279.6 mg, resp.) in crossover. The content of anthocyanin glucosides was detected in plasma and urinary excretion. Additionally, the plasmatic antioxidant activity was assessed after intake. Based on the plasma content, biokinetic criteria of the single anthocyanins were calculated, such as AUC, cmax, tmax, and the elimination rate t1/2. The urinary excretion of total anthocyanins differed significantly and amounted to 0.18% (red wine) and 0.23% (red grape juice) of the administered dose. Additionally, the plasmatic antioxidant activity increased to higher levels after juice ingestion compared to wine. The intestinal absorption of the anthocyanins of red grape juice seemed to be improved compared to red wine, suggesting a possible synergistic effect of the glucose content of the juice. The improved absorption resulted in an enhanced plasmatic bioactivity.