bluuebunny/crossref_metadata_2025 huggingface dataset:
Absorption spectra of e-beam-excited Ne, Ar, and Kr, pure and in binary mixtures
Authors: Levchenko A. O. , Ustinovskii N. N. , Zvorykin V. D.
Published: October 2010

A technique using the broadband emission of a laser plume as probe radiation is applied to record UV-visible (190–510 nm) absorption spectra of Ne, Ar, and Kr, pure and in binary mixtures under moderate e-beam excitation up to 1 MW/cm3. In all the rare gases and mixtures, the absorption spectra show continuum related to Rg2+ homonuclear ions [peaking at λ∼285, 295, and 320 nm in Ne, Ar, and Kr(Ar/Kr), respectively] and a number of atomic lines related mainly to Rg∗(ms) levels, where m is the lowest principal quantum number of the valence electron. In argon, a continuum related to Ar2∗ (λ∼325 nm) is also recorded. There are also trains of narrow bands corresponding to Rg2∗(npπ Π3g)←Rg2∗(msσ Σu+3) transitions. All the spectral features mentioned above were reported in literature but have never been observed simultaneously. Although charge transfer to a homonuclear ion of the heavier additive is commonly believed to dominate in binary rare-gas mixtures, it is found in this study that in Ne/Kr mixture, the charge is finally transferred from the buffer gas Ne2+ ion not to Kr2+ but to heteronuclear NeKr+ ion.
Restricted numerical range: A versatile tool in the theory of quantum information
Authors: Gawron Piotr , Puchała Zbigniew , Miszczak Jarosław Adam , Skowronek Łukasz , Życzkowski Karol
Published: October 2010

Numerical range of a Hermitian operator X is defined as the set of all possible expectation values of this observable among a normalized quantum state. We analyze a modification of this definition in which the expectation value is taken among a certain subset of the set of all quantum states. One considers, for instance, the set of real states, the set of product states, separable states, or the set of maximally entangled states. We show exemplary applications of these algebraic tools in the theory of quantum information: analysis of k-positive maps and entanglement witnesses, as well as study of the minimal output entropy of a quantum channel. Product numerical range of a unitary operator is used to solve the problem of local distinguishability of a family of two unitary gates.
Solid state dye sensitized solar cells based on supersonic beam deposition of organic, inorganic cluster assembled, and nanohybrid materials
Authors: Coppedè N. , Nardi M. , Toccoli T. , Tonezzer M. , Siviero F. , Micheli V. , Mayer A. C. , Iannotta S.
Published: October 2010

The growth of nanohybrids synthesized by supersonic beam codeposition of metal oxide clusters, produced by microplasma cluster source, and of aerodynamically accelerated molecules has been explored as a novel approach to the preparation of controlled dye sensitized materials for photovoltaic applications. The hybrid nanostructures are formed through deposition via supersonic expansion processes, controlling the kinetic energy of the precursors. With this approach, we developed prototype dye sensitized solar cells based on nanostructured TiO2 and CuPc with different architectures. To explore the viability of this approach, we compare cells made layer by layer with those where an intermediate codeposited layer is inserted between the two raw materials. This latter type of cells presents an enhancement of the photocurrent of a factor of 45 and of the efficiency of a factor of 40. This work opens a new viable perspective in the growth and in the control of the interfacial properties of nanohybrid materials, by direct codeposition of molecules and oxide nanostructures, with demonstrated useful applications in photovoltaic devices.
Generalized simulated tempering for exploring strong phase transitions
Authors: Kim Jaegil , Straub John E.
Published: October 2010

An extension of the simulation tempering algorithm is proposed. It is shown to be particularly suited to the exploration of first-order phase transition systems characterized by the backbending or S-loop in the statistical temperature or a microcanonical caloric curve. A guided Markov process in an auxiliary parameter space systematically combines a set of parametrized Tsallis-weight ensemble simulations, which are targeted to transform unstable or metastable energy states of canonical ensembles into stable ones and smoothly join ordered and disordered phases across phase transition regions via a succession of unimodal energy distributions. The inverse mapping between the sampling weight and the effective temperature enables an optimal selection of relevant Tsallis-weight parameters. A semianalytic expression for the biasing weight in parameter space is adaptively updated “on the fly” during the simulation to achieve rapid convergence. Accelerated tunneling transitions with a comprehensive sampling for phase-coexistent states are explicitly demonstrated in systems subject to strong hysteresis including Potts and Ising spin models and a 147 atom Lennard-Jones cluster.
A Review and Evaluation of the Phase Equilibria, Liquid-Phase Heats of Mixing and Excess Volumes, and Gas-Phase P
V
T Measurements for Nitrogen+Methane
Authors: Kidnay A. J. , Miller R. C. , Sloan E. D. , Hiza M. J.
Published: October 2010

The available experimental data for vapor–liquid equilibria, heat of mixing, change in volume on mixing for liquid mixtures, and gas-phase PVT measurements for nitrogen+methane have been reviewed and where possible evaluated for consistency. The derived properties chosen for analysis and correlation were liquid mixture excess Gibbs free energies, and Henry’s constants.
Energy Levels of Phosphorus, P i through P xv
Authors: Martin W. C. , Zalubas Romuald , Musgrove Arlene
Published: October 2010

Energy level data are given for the atom and all positive ions of phosphorus (Z=15). These data have been critically compiled, mainly from published and unpublished material on measurements and analyses of the optical spectra. We have derived or recalculated the levels for a number of the ions. In addition to the level values in cm−1 and the parity, the J value and the configuration and term assignments are listed if known. Leading percentages from the calculated eigenvectors are tabulated or quoted wherever available. Ionization energies are given for all spectra.
Assessing drought tolerance and regional patterns of genetic diversity among spring and winter bread wheat using simple sequence repeats and phenotypic data
Authors: Dodig Dejan , Zorić Miroslav , Kobiljski Borislav , Šurlan-Momirović Gordana , Quarrie Steve A.
Published: October 2010

This study was conducted to assess drought tolerance and regional-based patterns of diversity of bread wheat accessions and to identify new sources of diversity that could accelerate the development of improved wheat varieties better suited to meeting the challenges posed by changing climate in Southern and Eastern Europe. For this, genetic diversity assessed by simple sequence repeats (SSR) markers was compared with diversity evaluated using 19 phenotypic traits averaged over irrigated and drought-stress field conditions. Thirty-six SSR were used to profile 96 wheat genotypes from the collection of genetic resources at the Institute of Field and Vegetable Crops, Novi Sad, Serbia. A total of 46 loci and 366 alleles were detected, with a range of 3–21 alleles per locus. The polymorphic information content was estimated to be 0.61. The genetic distance for all possible 4560 pairs of genotypes ranged from 0.06 to 0.91 with an average of 0.65. Genotypes were grouped according to their drought tolerance (high, medium, low) and region of origin. Analysis of molecular variance showed that over 96% of the total variation could be explained by the variance within the drought tolerance and geographical groups. As a whole, genetic diversity among the high drought tolerance genotypes was considerably higher than that among low drought tolerance genotypes. Comparative analysis of SSR diversity among six regional groups revealed that the genotypes from North America exhibited more genetic diversity than those from other regions. Two dendrograms were constructed based on phenotypic and molecular analyses using the Unweighted Pair Group Method with Arithmetic Mean method and were found to be topologically different. Genotypes characterised as highly drought tolerant were distributed among all SSR-based cluster groups. This implied that the genetic basis of drought tolerance in these genotypes was different, thereby enabling wheat breeders to combine these diverse sources of genetic variability to improve drought tolerance in their breeding programs.
Genotypic variation in domesticated and wild accessions of the tropical tuberous legume Vigna vexillata (L.) A. Rich.
Authors: Damayanti F. , Lawn R. J. , Bielig L. M.
Published: October 2010

Vigna vexillata is an underutilised perennial tuberous legume with several multipurpose uses. In a comparative study to identify sources of potentially useful genetic variation, six cultivated accessions from two regions in Bali, a var. macrosperma accession and 12 wild accessions from Africa, Australia and Indonesia were evaluated for selected morphological, agronomic and phenological traits. Measurements were made of qualitative and quantitative traits on plants grown over the spring–autumn period in large pots on benches outdoors at Townsville, Australia (19°19.7′S, 146°45.7′E). Variation among the genotypes was assessed between the three main groups of accessions, between provenances within groups, and between accessions within provenances. Large variation was observed for most traits, with clear differentiation evident between the three main groups of accession. There was minimal variation within the Bali accessions for all except tuber attributes, while within the wild accessions there were some small differences due to provenance. The Bali accessions and var. macrosperma shared many attributes often associated with domestication, distinguishing them from the wild accessions. For example, the Bali accessions and var. macrosperma had broad-ovate leaflets, uniform-coloured seed testa, and non-dehiscent pods, and larger pods and seeds, seed yield per plant and seed harvest index than the wild accessions. Nonetheless, there were distinct differences between the Bali accessions and var. macrosperma. The Bali accessions had a larger seed size but fewer seeds per pod than var. macrosperma and were unique in having more than twice as many flowers per peduncle and a much longer duration of seed development than either var. macrosperma or the wild accessions. Whereas the Bali accessions were photoperiod-sensitive and as a consequence, late flowering and vegetatively vigorous, var. macrosperma was early flowering, more bush-like in habit and had higher seed yield and seed harvest index, all traits associated with domestication. Across all the accessions, there were significant correlations between many pairs of traits. While the present study identified sources of potentially useful variation, it was concluded that the lack of variation within the Bali accessions, combined with the paucity of both cultivated and var. macrosperma accessions in current germplasm collections, pose constraints to the future genetic improvement of V. vexillata.
Phosphorus and potassium nutrition of cotton: interaction with sodium
Authors: Rochester Ian J.
Published: October 2010

Poor phosphorus (P) and potassium (K) nutrition limits the growth and yield of many cotton (Gossypium hirsutum L.) crops in Australia. The demand for nutrients from cotton crops has risen as yields have increased over the past 40 years, and some soils have become depleted in these nutrients. Cotton is commonly grown on sodic soils that are more prone to nutritional problems. A survey of thirty-one sites over four years in northern NSW, Australia included twelve sites that had sodic topsoil. However, available soil P and K at all sites were above established critical values for cotton crops. Soil sodicity was negatively correlated with available soil P and K, and positively with soil salinity and chloride. Cotton leaf P and K concentrations at flowering were negatively correlated with leaf sodium (Na) concentration. The cotton crops growing in sodic soils produced 20% less dry matter (3 weeks before crop defoliation) and crop P and K uptake was reduced by 23% and 25%, respectively, whereas Na uptake was 107% higher. High soil sodicity also reduced the uptake of micro-nutrients. Two field experiments in adjacent sodic and non-sodic areas on one farm showed a yield response to P fertiliser application at the non-sodic site only, but where soil P availability was above the accepted critical value. Application of K fertiliser did not increase crop K uptake or yield. The lower yield and poorer growth of irrigated cotton on sodic soils was related to higher Na uptake and lower P and K uptake, possibly due to restricted root growth in sodic soils.
Source - sink balance and manipulating sink - source relations of wheat indicate that the yield potential of wheat is sink-limited in high-rainfall zones
Authors: Zhang Heping , Turner Neil C. , Poole Michael L.
Published: October 2010

Grain yield depends on the number of grains per unit area (sink) and the availability of assimilates (source) to fill these grains. The aim of the current work was to determine whether wheat yield in the high-rainfall zone of south-western Australia is limited in current cultivars by the size of the sink or by the assimilates available for grain filling. Three wheat cultivars (Calingiri, Chara and Wyalkatchem) and two breeding lines (HRZ216 and HRZ203) were grown in four replicates in the field from 2005 to 2007. Dry matter and water soluble carbohydrates (WSC) at anthesis and maturity were measured and used to determine the source and sink balance of the crop. In 2007, three further treatments were applied to manipulate the sink–source relationships: (i) spikelets were removed on main stems to increase the source : sink ratio; (ii) incoming solar radiation was reduced by 40% by shading after anthesis to reduce the availability of assimilates to grains; and (iii) supplemental irrigation was used to maintain the capacity for photosynthesis by an improved water supply during grain filling. The source–sink balance of the crops showed that the potential source was 25% greater than the actual grain yield in average and above-average seasons (2005 and 2007), suggesting that sink size, represented by the number of grain per unit area, was a limiting factor to yield potential. However, the source may have become a limiting factor in a drought season (2006). The grain yield increased with increased number of grains/m2 and kernel weight remained relatively stable even when grain number increased from 7000 to 16 000 per m2. The removal of half of the spikelets on the main stem did not increase kernel mass of the remaining grains and an additional 33 mm of irrigation water did not increase grain yield, but significantly (P < 0.05) increased WSC left in stems and leaf sheaths at maturity. Shading after anthesis did not significantly reduce grain yield of the current cultivars Calingiri and Wyalkatchem, but it reduced grain yield by 23–25% (P < 0.05) in Chara and HRZ203. The source–sink balance over three seasons and three independent experiments in 2007 suggested that the yield of the current wheat cultivars is more sink- than source-limited and that breeding wheat with a larger sink size than in the current cultivars may lift the yield potential of wheat in the high-rainfall zone of south-western Australia.
Nationalism and socialism: “Phase D” in the Belarusian nation-building
Authors: Bekus Nelly
Published: October 2010

This article presents the history of Belarusian national development in the light of Miroslav Hroch's theory and demonstrates how the initial process of national awakening typical for small nations in eastern and central Europe in the late nineteenth and early twentieth century described by M. Hroch continued under Soviet rule after the Bolshevik revolution. Changes which were brought to Belarusian society together with socialist modernization in the Soviet state constituted “Phase D” (a term coined by Terry Martin) in Belarusian nation-building. As the history of Belarusian nation-formation illustrates, Hroch's scheme of three phases of national movements within small nations ignored a specific mode of small nations’ development in a multiethnic state and within the socialist formation. At the same time, the question about the status of the Soviet era's achievements in Belarusian national development appears to be an important issue for understanding the current political development in the country.
Nation-formation and national movement(s) in Pakistan: a critical estimation of Hroch's stage theory
Authors: Siddiqi Farhan
Published: October 2010

The present article critically evaluates Hroch's theory in light of the Sindhi and Baloch national movements in Pakistan. At the heart of the issue are the social preconditions and the stage theory which Hroch posits to comprehend both the formation of nations and origins of the national movement. As far as social preconditions are concerned, the article contests the overarching notion in Hroch's theory that only when a complete class structure develops that the nation comes into being and the national movement itself is successful. With respect to the stage theory, the article brings into contention the variable of “intra-ethnic conflict” or the conflicts which inheres within nations. This makes the linear progression from Stage A to B to C, as Hroch identifies, difficult to achieve because within a single nation multiple national movements exist. In such a scenario, one can depict a stage theory for each national movement within a single nation. Finally, I argue, that in order to understand nation formation and national movements, it is imperative that the ideological orientation of national movements, or in other words, nationalism should also be put in proper perspective.
Comments
Authors: Hroch Miroslav
Published: October 2010

After having published a book, an author must take into account that his text remains unprotected, and becomes an object of new readings which reflect different social and political conditions, and the interests of subsequent generations of readers. Consequently, an author's concepts and opinions are open to various reflections and can be used as arguments or tools of analysis, as inspirations, models, or targets of criticism. These processes occur independently of an author's expectations and original goals. In a broader sense, we can agree with antiquity: “Habent sua fata libelli.” My book on the “Social Preconditions of National Revival” has been no exception, and it is a great pleasure for me to realize that this book has survived so many decades to live its “second life,” and that its original meanings and concepts inspire new interpretations, even if they have sometimes been misunderstood or exploited as arguments in totally different conditions and settings. It is a pleasant surprise to observe that my methods, typologies and generalizations can be (successfully?) discussed and used, naturally in a modified version, as tools to analyze developments and conflicts in very distant countries and times. Alexander Maxwell has given an excellent and well-informed overview of this differentiated and sometimes controversial second life. All other contributions to this issue, analyzing concrete cases, could be understood as indications that my scientific efforts have made sense, and sometimes inspired researchers up to the present day.
Transplant or graft? Hroch and the Mexican patriotic movements
Authors: Hoyo Henio
Published: October 2010

In his highly influential work on the “small,” stateless European nations, Hroch seems to assume that patriotic movements have a homogeneous view about the core relations or “ties” that constitute and identify their nations. This assumption seems generally correct for the cases Hroch studies. However, is it correct if applied to the study of those patriotic movements developing in comparatively larger, heterogeneous and underdeveloped societies, comprising several ethnic groups bound together by the colonialist rule of an autocratic empire? I argue that, while the colonial experience can lead to the creation of some ties among the dominated populations, it also affects the way patriotic movements perceive their own nations. As a result, the phase of patriotic agitation can involve diverse movements addressing the same nation, but each having a particular view on the features and history of it. Such contested patriotic doctrines can lead to very important variations in the political agendas and goals of those movements, especially when they reach the mass phase. To exemplify this, the nineteenth century movements in New Spain/Mexico will be used as an example.
A Gap Hazard Analysis: Initiating Policy Development with Mountainous Communities
Authors: Strickert G. , Smarasinghe S. , Doscher C. , Davies T.
Published: October 2010

We present a conceptual framework and methodology for policy development research in complex, uncertain, and data-poor environments with the objective of sustainable hazard mitigation. Creating effective policies for improving resilience to natural catastrophes in general and developing policy initiatives to help manage earthquakes in particular requires a conceptual framework whose formulation should engage lay-experts and experts as essential members of the research process. This paper outlines a framework and applied case study as a starting point for identifying policies that increase resilience to earthquakes or other low probability high consequences events. The methodology integrates geomorphic assessments, qualitative interviews, and fuzzy cognitive maps with three stakeholder groups for simulating policies scenarios. The results indicate that an integrated gap hazard analysis embedded in a policy framework for increasing resilience to earthquakes in New Zealand ski areas does identify ‘gaps’ in stakeholders' hazard perceptions and awareness. Furthermore, the framework is a useful first step toward policy development for hazards beyond current horizons.
Early Antiplatelet Therapy in Coronary Artery Bypass Grafting a Calculated Benefit
Authors: Trachiotis Gregory D.
Published: October 2010

Studies have demonstrated that antagonists of platelet activity, including aspirin and clopidogrel, reduce the risk of major adverse events in patients with acute coronary syndromes. Although antiplatelet agents also convey an increased risk of bleeding, particularly in patients proceeding to coronary artery bypass graft surgery, in most cases, the benefits of early initiation of antiplatelet therapy outweigh the risks. The purpose of this review is to distinguish perceived and actual risk versus the benefit associated with early antiplatelet therapy to help clinicians make informed decisions on using these agents in an acute setting where patients may require coronary artery bypass grafting.
A Novel Technology for Large Vessel Recanalization
Authors: Weitzman Yosi , Ben-Porath Ariel , Levitsky Michael , Jonas Michael , Gross Yossi , Osiroff Ricardo , Kirshenbaum Izik
Published: October 2010

Large vessels recanalization is a challenge for mechanical atherectomy devices, where the lumen debulked is close in diameter to the device crossing profile, which may be only 25% to 30% of the original lumen size; so, the procedure can restore only a fraction of the original blood flow. Moreover, small diameter lumens are prone to be repeatedly occluded after a relatively short period of time. In this article, we present a novel technology of recanalization, using a catheter-based microjet system to deliver a flux of biocompatible abrasive particles to the lesion site, resulting in microchipping of the plaque, while minimizing trauma to the vessel wall. Plaque debris is removed from the blood flow, and blood flow is restored. In contrast to rotating mechanical devices, plaque debulking can be performed up to diameters that are substantially larger than the device crossing profile, supporting superior long-term patency. As a case study, we evaluated the technology for use in the superficial femoral artery where the lesions tend to be very long and heavily calcified with high restenosis rates.
Minimally Invasive Video-Assisted Epicardial Lead Cardiac Resynchronization Therapy for the Dilated Cardiomyopathy Heart Failure Cases
Authors: Zhang Hai-Bo , Meng Xu , Han Jie , Li Yan , Zeng Ya-Ping , Zhang Ye
Published: October 2010

Objective

Cardiac resynchronization therapy (CRT) with biventricular pacing has demonstrated cardiac function improvement in treating congestive heart failure. Traditional CRT through coronary sinus lead method is difficult to perform. Minimally invasive video-assisted epicardial lead (Epi-lead) CRT for the dilated cardiomyopathy heart failure cases was explored.

Methods

From April 2007 to June 2009, a total of 12 patients (age, 63 ± 9 years) with depressed systolic left ventricular (LV) function (ejection fraction, <35%), left bundle branch block (mean QRS [Q wave, R wave, S wave], 158 ± 15 milliseconds), and congestive heart failure of New York Heart Association class III/IV were enrolled. The patients received minimally invasive video-assisted epicardial steroid-eluting LV lead implantation for the CRT. The right atrial and right ventricle leads were implanted, guided by x-ray. The mean follow-up time was 13.7 months (range, 7–27 months).

Results

All patients received LV lead implantation at the most late-activated site. The mean QRS duration decreased significantly from 158 ± 15 to 124 ± 11 milliseconds (P < 0.05). There was no surgical or hospital mortality in the entire series. The mean procedure duration (skin to skin) of the LV lead implantation was 52.4 ± 15.8 minutes. The mean postoperative stay was 7.1 ± 2.7 days. During the follow-up, cardiac function improved significantly in 11 patients. Threshold capture of the Epi-leads remained stable at 1.12 ± 0.3 V/0.5 ms during the follow-up. None died during the follow-up.

Conclusions

Surgical Epi-lead placement for the resynchronization therapy is a safe and reliable technique and should be considered as an equal alternative.
Stentless Aortic Valve Implantation through an Upper Manubrium-Limited V-Type Ministernotomy
Authors: Karimov Jamshid H. , Cerillo Alfredo Giuseppe , Gasbarri Tommaso , Solinas Marco , Bevilacqua Stefano , Glauber Mattia
Published: October 2010

In this piece of work, we attempt to highlight our approach and early experience with minimally invasive aortic valve replacement with aortic Freedom Solo stentless bioprosthesis performed through an upper manubrium-limited ministernotomy in the second intercostal space. The novel suturing technique is required for stentless aortic bioprosthesis implantation, and this, in its turn, will predetermine and influence the surgeon's choice for operative access. In our department, the feasibility of the approach was first assessed; aortic valve was replaced by stentless bioprosthesis in a total of 23 patients (mean age 57 ± 12 years). In all cases, a cardiopulmonary bypass was established by a central ascending aorta cannulation and peripheral percutaneous venous cannula insertion. This approach was found to be technically reproducible and safe. The surgical technique used is described in this article.
Refractory Bartonella quintana bacillary angiomatosis following chemotherapy for chronic lymphocytic leukaemia
Authors: Holmes Natasha E. , Opat Stephen , Kelman Anthony , Korman Tony M.
Published: October 2010

Bacillary angiomatosis is a well-recognized infection with cutaneous and systemic manifestations caused byBartonella henselaeorBartonella quintanaand occurs in immunocompromised patients. We report a case ofB. quintanabacillary angiomatosis following fludarabine-based chemotherapy for chronic lymphocytic leukaemia that was refractory to standard treatment and was complicated by lymphadenopathy and osteomyelitis.
Increased human pathogenic potential of Escherichia coli from polymicrobial urinary tract infections in comparison to isolates from monomicrobial culture samples
Authors: Croxall Gemma , Weston Vivienne , Joseph Susan , Manning Georgina , Cheetham Phil , McNally Alan
Published: October 2010

The current diagnostic standard procedure outlined by the Health Protection Agency for urinary tract infections (UTIs) in clinical laboratories does not report bacteria isolated from samples containing three or more different bacterial species. As a result many UTIs go unreported and untreated, particularly in elderly patients, where polymicrobial UTI samples are especially prevalent. This study reports the presence of the major uropathogenic species in mixed culture urine samples from elderly patients, and of resistance to front-line antibiotics, with potentially increased levels of resistance to ciprofloxacin and trimethoprim. Most importantly, the study highlights that Escherichia
coli present in polymicrobial UTI samples are statistically more invasive (P<0.001) in in vitro epithelial cell infection assays than those isolated from monomicrobial culture samples. In summary, the results of this study suggest that the current diagnostic standard procedure for polymicrobial UTI samples needs to be reassessed, and that E. coli present in polymicrobial UTI samples may pose an increased risk to human health.
Molecular analysis of faecal and duodenal samples reveals significantly higher prevalence and numbers of Pseudomonas aeruginosa in irritable bowel syndrome
Authors: Kerckhoffs Angèle P. M. , Ben-Amor Kaouther , Samsom Melvin , van der Rest Michel E. , de Vogel Joris , Knol Jan , Akkermans Louis M. A.
Published: October 2010

Intestinal microbiota may play a role in the pathophysiology of irritable bowel syndrome (IBS). In this case–control study, mucosa-associated small intestinal and faecal microbiota of IBS patients and healthy subjects were analysed using molecular-based methods. Duodenal mucosal brush and faecal samples were collected from 37 IBS patients and 20 healthy subjects. The bacterial 16S rRNA gene was amplified and analysed using PCR denaturing gradient gel electrophoresis (DGGE). Pooled average DGGE profiles of all IBS patients and all healthy subjects from both sampling sites were generated and fingerprints of both groups were compared. The DGGE band fragments which were confined to one group were further characterized by sequence analysis. Quantitative real-time PCR (q-PCR) was used to quantify the disease-associated microbiota. Averaged DGGE profiles of both groups were identical for 78.2 % in the small intestinal samples and for 86.25 % in the faecal samples. Cloning and sequencing of the specific bands isolated from small intestinal and faecal DGGE patterns of IBS patients showed that 45.8 % of the clones belonged to the genus Pseudomonas, of which Pseudomonas aeruginosa was the predominant species. q-PCR analysis revealed higher levels (P<0.001) of P. aeruginosa in the small intestine of IBS patients (8.3 %±0.950) than in the small intestine of healthy subjects (0.1 %±0.069). P. aeruginosa was also significantly (P<0.001) more abundant (2.34 %±0.31) in faeces of IBS patients than in faeces of healthy subjects (0.003 %±0.0027). This study shows that P. aeruginosa is detected more frequently and at higher levels in IBS patients than in healthy subjects, suggesting its potential role in the pathophysiology of IBS.
Application of quantitative PCR to the diagnosis and monitoring of Pseudomonas aeruginosa colonization in 5–18-year-old cystic fibrosis patients
Authors: Billard-Pomares Typhaine , Herwegh Stéphanie , Wizla-Derambure Nathalie , Turck Dominique , Courcol René , Husson Marie-Odile
Published: October 2010

Early detection of Pseudomonas aeruginosa and early aggressive treatment are recommended to delay chronic infection in cystic fibrosis (CF) patients. The aim of this study was to assess a quantitative PCR (q-PCR) assay for the diagnosis of early P. aeruginosa colonization in 23 young CF patients (group A, age range 7–18 years) and to survey the eradication of P. aeruginosa in 10 young CF patients (group B, age range 5–18 years) after an initial antibiotic treatment. q-PCR results for consecutive sputum samples from each patient during a period of 18 months were compared with bacterial cultures during the same period plus an additional period of 12 months, and with concomitant clinical signs of pulmonary exacerbation. The q-PCR and bacterial cultures were negative for 17 of the 23 patients in group A and six of the 10 patients in group B during the study period. However, consecutive positive q-PCR results were observed for one patient in group A and three patients in group B, while the bacterial cultures for the same sputum sample remained negative. They preceded positive P. aeruginosa bacterial cultures at 7 and 8 months for two patients in group B. These positive results were associated with a worsening of the clinical status of patients, but pulmonary exacerbation appeared non-specific for the diagnosis of early P. aeruginosa colonization since pulmonary exacerbations were observed in patients in whom q-PCR or bacterial culture remained negative. In conclusion, q-PCR may be a useful additional tool to provide information on the P. aeruginosa status of CF patients.
Caspofungin primes the immune response of the larvae of Galleria mellonella and induces a non-specific antimicrobial response
Authors: Kelly Judy , Kavanagh Kevin
Published: October 2010

The echinocandins (e.g. caspofungin) function by inhibiting the synthesis of 1,3-β-glucan in the fungal cell wall. While the potent antifungal activity of caspofungin has been well characterized in mammals, this study investigated the in vivo antifungal effect of caspofungin using larvae of the insect Galleria mellonella. Caspofungin was successful in increasing the survival of larvae that were inoculated with Candida albicans 1 h before the drug was administered, particularly when a concentration of 0.19 μg ml−1 was used. Pre-injecting larvae with caspofungin also increased their survival when they were inoculated with either Staphylococcus aureus or C. albicans. Caspofungin administration resulted in an increase in the number of circulating immune cells (haemocytes), an increase in the expression of the genes encoding IMPI and transferrin, and an increase in the expression of a number of proteins (identified by liquid chromatography–mass spectrometry) some of which have immune functions. This work indicates that administration of caspofungin can increase the survival of infected G. mellonella larvae, and this is due to the antifungal properties of caspofungin and also to the ability of caspofungin to prime the insect's immune response.
Control of melanocyte differentiation by a MITF–PDE4D3 homeostatic circuit
Authors: Khaled Mehdi , Levy Carmit , Fisher David E.
Published: October 2010

Cyclic AMP (cAMP) is a ubiquitous second messenger that regulates a variety of biological processes. The magnitude and duration of cAMP expression are regulated by both production and hydrolysis. Melanocyte-stimulating hormone (MSH) plays a crucial role in pigment cell differentiation via cAMP-regulated expression of the master transcription factor MITF. We report the identification of phosphodiesterase 4D3 as a direct target of the MSH/cAMP/MITF pathway. This creates a negative feedback loop that induces refractoriness to chronic stimulation of the cAMP pathway in melanocytes. This homeostatic pathway highlights a potent mechanism controlling melanocyte differentiation that may be amenable to pharmacologic manipulation for skin cancer prevention.
Induced pluripotency: history, mechanisms, and applications
Authors: Stadtfeld Matthias , Hochedlinger Konrad
Published: October 2010

The generation of induced pluripotent stem cells (iPSCs) from somatic cells demonstrated that adult mammalian cells can be reprogrammed to a pluripotent state by the enforced expression of a few embryonic transcription factors. This discovery has raised fundamental questions about the mechanisms by which transcription factors influence the epigenetic conformation and differentiation potential of cells during reprogramming and normal development. In addition, iPSC technology has provided researchers with a unique tool to derive disease-specific stem cells for the study and possible treatment of degenerative disorders with autologous cells. In this review, we summarize the progress that has been made in the iPSC field over the last 4 years, with an emphasis on understanding the mechanisms of cellular reprogramming and its potential applications in cell therapy.
Sept4/ARTS is required for stem cell apoptosis and tumor suppression
Authors: García-Fernández María , Kissel Holger , Brown Samara , Gorenc Travis , Schile Andrew J. , Rafii Shahin , Larisch Sarit , Steller Hermann
Published: October 2010

Inhibitor of Apoptosis Proteins (IAPs) are frequently overexpressed in tumors and have become promising targets for developing anti-cancer drugs. IAPs can be inhibited by natural antagonists, but a physiological requirement of mammalian IAP antagonists remains to be established. Here we show that deletion of the mouse Sept4 gene, which encodes the IAP antagonist ARTS, promotes tumor development. Sept4-null mice have increased numbers of hematopoietic stem and progenitor cells, elevated XIAP protein, increased resistance to cell death, and accelerated tumor development in an Eμ-Myc background. These phenotypes are partially suppressed by inactivation of XIAP. Our results suggest that apoptosis plays an important role as a frontline defense against cancer by restricting the number of normal stem cells.
Evidence for and against regional differences in neural stem and progenitor cells of the CNS: Figure 1.
Authors: Becher Oren J. , Holland Eric C.
Published: October 2010

Neural stem and progenitor cells (NSCs) give rise to the cellular diversity of the CNS. There is evidence both for and against differences in these cells based on the region of the brain in which they reside. Primary brain tumors mimic many aspects of NSC behavior. Recent data suggest that some of the variability in glioma biology may be, in part, a reflection of regional differences in the NSCs from which they arise. In this issue of Genes & Development, Lee and colleagues (pp. 2317–2329) examine how NF1 regulates NSC proliferation and glial differentiation in the brainstem and cortex of the postnatal mouse brain.
Building p53: Figure 1.
Authors: Terzian Tamara , Lozano Guillermina
Published: October 2010

The intricacies of p53 regulation just got more complex. While much is known about the transcriptional regulation of p53 target genes, Chen and Kastan (pp. 2146–2156) uncovered a new mechanism regarding the making of the p53 protein itself. In the October 1, 2010, issue of Genes & Development, they introduced us to a novel mechanism of p53 translational control, by which a 5′–3′ cap-independent, poly(A)-independent, RNA–RNA interaction enhances p53 translation by binding the ribosomal protein RPL26 following DNA damage. Oligonucleotides designed against this 5′–3′ untranslated region (UTR) duplex disrupted the binding of RPL26 to p53 mRNA and reduced p53 synthesis and, therefore, function. This study reveals an alternate mechanism of translational control to regulate p53 levels.
Dependence of recruitment on parent stock of the spiny lobster, Panulirus argus, in Florida
Authors: EHRHARDT NELSON M. , FITCHETT MARK D.
Published: October 2010

Despite management practices to achieve sustainability, commercial landings for Florida spiny lobster (Panulirus argus) have experienced a drastic decline (57%) since 2000. This is cause for concern not only for economic reasons, but for issues of sustainability. An annual index of P. argus post‐larval (puerulus) abundance, estimated with a generalized linear model with significant mean sea‐level effects, shows a 36% decrease in annual puerulus supply since 1988. In addition, local Florida spawning stock biomass estimated from an age‐structured sequential population analysis decreased 57% since 1988. Puerulus abundance follows a highly correlated (R = 0.76) trend with a 12‐month delayed spawning stock abundance, which supports the contention that the Florida spawning population is a significant contributing factor to post‐larval recruitment in Florida. Residuals about the puerulus on spawning stock abundance function follow closely an interannual North Atlantic Oscillation Index signal. This residual effect is thought of as a secondary regional population effect on Florida puerulus recruitment. The Florida spiny lobster stock is exploited with no fishing mortality controls due to the Pan Caribbean recruitment concept adopted in Florida spiny lobster management. Therefore, the potential of recruitment overfishing exists if fishing mortality controls to protect local spawning stock abundance, such as catch quotas, are not introduced.
Ocean scale hypoxia‐based habitat compression of Atlantic istiophorid billfishes
Authors: PRINCE ERIC D. , LUO JIANGANG , PHILLIP GOODYEAR C. , HOOLIHAN JOHN P. , SNODGRASS DERKE , ORBESEN ERIC S. , SERAFY JOSEPH E. , ORTIZ MAURICIO , SCHIRRIPA MICHAEL J.
Published: October 2010

Oxygen minimum zones (OMZs) below near‐surface optimums in the eastern tropical seas are among the largest contiguous areas of naturally occurring hypoxia in the world oceans, and are predicted to expand and shoal with global warming. In the eastern tropical Pacific (ETP), the surface mixed layer is defined by a shallow thermocline above a barrier of cold hypoxic water, where dissolved oxygen levels are ≤3.5 mL L−1. This thermocline (∼25–50 m) constitutes a lower hypoxic habitat boundary for high oxygen demand tropical pelagic billfish and tunas (i.e., habitat compression). To evaluate similar oceanographic conditions found in the eastern tropical Atlantic (ETA), we compared vertical habitat use of 32 sailfish (Istiophorus platypterus) and 47 blue marlin (Makaira nigricans) monitored with pop‐up satellite archival tags in the ETA and western North Atlantic (WNA). Both species spent significantly greater proportions of their time in near‐surface waters when inside the ETA than when in the WNA. We contend that the near‐surface density of billfish and tunas increases as a consequence of the ETA OMZ, therefore increasing their vulnerability to overexploitation by surface gears. Because the ETA OMZ encompasses nearly all Atlantic equatorial waters, the potential impacts of overexploitation are a concern. Considering the obvious differences in catchability inside and outside the compression zones, it seems essential to standardize these catch rates separately to minimize inaccuracies in stock assessments for these species. This is especially true in light of global warming, which will likely exacerbate future compression impacts.
Measuring copepod abundance in deep‐water winter habitats in the NE Norwegian Sea: intercomparison of results from laser optical plankton counter and multinet
Authors: GAARDSTED FRANK , TANDE KURT S. , BASEDOW SÜNNJE L.
Published: October 2010

The main purpose of this study was to assess the usefulness of the laser optical plankton counter (LOPC) as a Calanus finmarchicus monitoring tool in the NE Norwegian Sea in winter. To test this, a multinet and an LOPC were used simultaneously to sample overwintering copepods in the Lofoten basin in January 2007. Additional data from an LOPC laboratory experiment were also analyzed to help the interpretation of the field data. Both the laboratory data and the field data indicated that the presence of particles other than zooplankton generally contaminated the zooplankton signal in the LOPC data. However, reliable abundance estimates could be made from the LOPC data by choosing an appropriate size range in the LOPC size distribution. This size range was determined by comparing LOPC abundance estimates from systematically varying size ranges to multinet zooplankton abundance data. The average difference was smallest for a size range of about 900–1500 μm. As C. finmarchicus, stages IV and V, was by far the most abundant species in the NE Norwegian Sea, abundance estimates from the LOPC in this size range were in practice estimates of C. finmarchicus abundance, making the LOPC suitable as a tool for providing high resolution winter data in the NE Norwegian Sea.
Meridional patterns in the deep scattering layers and top predator distribution in the central equatorial Pacific
Authors: HAZEN ELLIOTT L. , JOHNSTON DAVID W.
Published: October 2010

The deep scattering layers (DSL) in the central equatorial Pacific form an important prey resource in a relatively oligotrophic habitat. In March of 2006, we used a calibrated 38‐kHz SIMRAD EK60 scientific sonar to assess the spatial distribution of the deep scattering layer relative to broad‐scale oceanographic features and fine‐scale physical and biological measurements. We conducted a single continuous transect from approximately 10°S to 20°N at 170°W while measuring acoustic backscatter, current velocity and direction, temperature, salinity, oxygen, and fluorescence with depth, coincident with marine mammal occurrence. These data were combined with remotely sensed sea surface height, chlorophyll, and sea surface temperature data to examine patterns in DSL distribution. To analyze DSL density with depth, acoustic backscatter was binned into surface (<200 m), mid (200–550 m) and deep (550–1000 m) layers. Backscatter was highly correlated with chlorophyll‐a and low sea surface height anomalies and was greatest near the equator. We found high diel variability in DSL depth and scattering intensity between the mid and surface layers as well as a shallowing of the deep layer moving northward across the equator. Marine mammal sightings consisted primarily of odontocetes with their distribution coincident with higher acoustic densities of their forage base. Shifts in DSL distribution and scattering intensity are an important component towards understanding the behavior and distribution of highly migratory predator species.
Predicting the occurrence of Atlantic bluefin tuna (Thunnus thynnus) larvae in the northern Gulf of Mexico: building a classification model from archival data
Authors: MUHLING BARBARA A. , LAMKIN JOHN T. , ROFFER MITCHELL A.
Published: October 2010

Although bluefin tuna are found throughout the Atlantic Ocean, spawning in the western Atlantic has been recorded predominantly in the Gulf of Mexico (GOM) in spring. Larval bluefin tuna abundances from the northern GOM are formulated into an index used to tune the adult stock assessment, and the variability of this index is currently high. This study investigated whether some of the variability in larval bluefin tuna abundances was related to environmental conditions, by defining associations between larval bluefin tuna catch locations, and a suite of environmental variables. We hypothesized that certain habitat types, as defined by environmental variables, would be more likely to contain bluefin tuna larvae. Favorable habitat for bluefin tuna larvae was defined using a classification tree approach. Habitat within the Loop Current was generally less favorable, as were warm‐core rings, and cooler waters on the continental shelf. The location and size of favorable habitat was highly variable among years, which was reflected in the locations of larval bluefin tuna catches. The model successfully placed bluefin tuna larvae in favorable habitat with nearly 90% accuracy, but many negative stations were also located within theoretically favorable habitat. The probability of collecting larval bluefin tuna in favorable habitat was nearly twice the probability of collecting bluefin tuna larvae across all habitats (35.5 versus 21.0%). This model is a useful addition to knowledge of larval bluefin tuna distributions; however, the incorporation of variables describing finer‐scale features, such as thermal fronts, may significantly improve the model’s predictive power.