bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemokine profile of disc degeneration with acute or chronic pain
Authors: Schroeder Malte , Viezens Lennart , Schaefer Christian , Friedrichs Barbara , Algenstaedt Petra , Rüther Wolfgang , Wiesner Lothar , Hansen-Algenstaedt Nils
Published: March 2013

Object

Disc-related disorders such as herniation and chronic degenerative disc disease (DDD) are often accompanied by acute or chronic pain. Different mediators have been identified in the development of radicular pain and DDD. Previous studies have not analyzed individual cytokine profiles discriminating between acute sciatic and chronic painful conditions, nor have they distinguished between different anatomical locations within the disc. The aim of this study was to elucidate the protein biochemical mechanisms in DDD.

Methods

The authors determined expression levels of matrix metalloproteinase–3, transforming growth factor–β (TGF-β), tumor necrosis factor–α, interleukin-1α, and pro-substance P using enzyme-linked immunosorbent assay and Western blot analyses in patients suffering from DDD (n = 7), acute back pain due to herniated discs with radiculopathy (n = 7), and a control group (n = 7). Disc tissue samples from the anulus fibrosus (AF) and nucleus pulposus (NP) were analyzed. Statistical analysis was performed using nonparametric tests.

Results

A distinct distribution of cytokines was found in different anatomical regions of intervertebral discs in patients with DDD and herniated NP. Increased TGF-β levels were predominantly found in DDD. Matrix metalloproteinase–3 was increased in acute herniated disc material. Increased levels of substance P were found in patients suffering from DDD but not in patients with disc herniation. The data showed significantly higher levels of proinflammatory cytokines in the AF and NP of patients with DDD, and the expression levels in the AF were even higher than in the NP, suggesting that the inflammatory response initiates from the AF.

Conclusions

These results highlight the complex mechanisms involved during disc degeneration and the need to distinguish between acute and chronic processes as well as different anatomical regions, namely the AF and NP. They also highlight potential problems in disc nucleus replacement therapies because the results suggest a biochemical link between AF and NP cytokine expression.
State Space System Identification of 3-Degree-of-Freedom (DOF) Piezo-Actuator-Driven Stages with Unknown Configuration
Authors: Cao Yu , Chen Xiongbiao
Published: March 2013

Due to their fast response, high accuracy and non-friction force, piezo-actuators have been widely employed in multiple degree-of-freedom (DOF) stages for various nano-positioning applications. The use of flexible hinges in these piezo-actuator-driven stages allows the elimination of the influence of friction and backlash clearance, as observed in other configurations; meanwhile it also causes more complicated stage performance in terms of dynamics and the cross-coupling effect between different axes. Based on the system identification technique, this paper presents the development of a model for the 3-DOF piezo-actuator-driven stages with unknown configuration, with its parameters estimated from the Hankel matrix by means of the maximum a posteriori (MAP) online estimation. Experiments were carried out on a commercially-available piezo-actuator-driven stage to verify the effectiveness of the developed model, as compared to other methods. The results show that the developed model is able to predict the stage performance with improved accuracy, while the model parameters can be well updated online by using the MAP estimation. These capabilities allow investigation of the complicated stage performance and also provide a starting point from which the mode-based control scheme can be established for improved performance.
Emission of β+ Particles Via Internal Pair Production in the 0+ – 0+ Transition of 90Zr: Historical Background and Current Applications in Nuclear Medicine Imaging
Authors: D'Arienzo Marco
Published: March 2013

90Y is traditionally considered as a pure β– emitter. However, the decay of this radionuclide has a minor branch to the 0+ first excited state of 90Zr at 1.76 MeV, that is followed by a β+/β– emission. This internal pair production has been largely studied in the past because it is generated by a rare electric monopole transition (E0) between the states 0+/0+ of 90Zr. The positronic emission has been recently exploited for nuclear medicine applications, i.e. positron emission tomography (PET) acquisitions of 90Y-labelled radiopharmaceuticals, widely used as therapeutic agents in internal radiation therapy. To date, this topic is gaining increasing interest in the radiation dosimetry community, as the possibility of detecting β+ emissions from 90Y by PET scanners may pave the way for an accurate patient-specific dosimetry. This could lead to an explosion in scientific production in this field. In the present paper the historical background behind the study of the internal pair production of the 0+/0+ transition of 90Zr is presented along with most up to date measured branch ratio values. An overview of most recent studies that exploit β+ particles emitted from 90Y for PET acquisitions is also provided.
Mirk/dyrk1B Kinase in Ovarian Cancer
Authors: Friedman Eileen
Published: March 2013

Mirk/dyrk1B kinase is expressed in about 75% of resected human ovarian cancers and in most ovarian cancer cell lines with amplification in the OVCAR3 line. Mirk (minibrain-related kinase) is a member of the Minibrain/dyrk family of related serine/threonine kinases. Mirk maintains cells in a quiescent state by stabilizing the CDK inhibitor p27 and by inducing the breakdown of cyclin D isoforms. Mirk also stabilizes the DREAM complex, which maintains G0 quiescence by sequestering transcription factors needed to enter cycle. By entering a quiescent state, tumor cells can resist the nutrient deficiencies, hypoxic and acidic conditions within the tumor mass. Mirk maintains the viability of quiescent ovarian cancer cells by reducing intracellular levels of reactive oxygen species. CDKN2A-negative ovarian cancer cells treated with a Mirk kinase inhibitor escaped G0/G1 quiescence, entered cycle with high ROS levels and underwent apoptosis. The ROS scavenger N-acetyl cysteine reduced the extent of cancer cell loss. In contrast, the Mirk kinase inhibitor slightly reduced the fraction of G0 quiescent diploid epithelial cells and fibroblasts, and the majority of the cells pushed into cycle accumulated in G2 + M. Apoptotic sub-G0/G1 cells were not detected. Thus, normal cells were spared because of their expression of CDK inhibitors that blocked unregulated cycling and Mirk kinase inhibitor-treated normal diploid cells were about as viable as untreated controls.
Recent Advances in the Discovery and Development of Marine Microbial Natural Products
Authors: Xiong Zhi-Qiang , Wang Jian-Feng , Hao Yu-You , Wang Yong
Published: March 2013

Marine microbial natural products (MMNPs) have attracted increasing attention from microbiologists, taxonomists, ecologists, agronomists, chemists and evolutionary biologists during the last few decades. Numerous studies have indicated that diverse marine microbes appear to have the capacity to produce an impressive array of MMNPs exhibiting a wide variety of biological activities such as antimicrobial, anti-tumor, anti-inflammatory and anti-cardiovascular agents. Marine microorganisms represent an underexplored reservoir for the discovery of MMNPs with unique scaffolds and for exploitation in the pharmaceutical and agricultural industries. This review focuses on MMNPs discovery and development over the past decades, including innovative isolation and culture methods, strategies for discovering novel MMNPs via routine screenings, metagenomics, genomics, combinatorial biosynthesis, and synthetic biology. The potential problems and future directions for exploring MMNPs are also discussed.
The Deep-Sea Natural Products, Biogenic Polyphosphate (Bio-PolyP) and Biogenic Silica (Bio-Silica), as Biomimetic Scaffolds for Bone Tissue Engineering: Fabrication of a Morphogenetically-Active Polymer
Authors: Wang Xiaohong , Schröder Heinz , Feng Qingling , Draenert Florian , Müller Werner
Published: March 2013

Bone defects in human, caused by fractures/nonunions or trauma, gain increasing impact and have become a medical challenge in the present-day aging population. Frequently, those fractures require surgical intervention which ideally relies on autografts or suboptimally on allografts. Therefore, it is pressing and likewise challenging to develop bone substitution materials to heal bone defects. During the differentiation of osteoblasts from their mesenchymal progenitor/stem cells and of osteoclasts from their hemopoietic precursor cells, a lineage-specific release of growth factors and a trans-lineage homeostatic cross-talk via signaling molecules take place. Hence, the major hurdle is to fabricate a template that is functioning in a way mimicking the morphogenetic, inductive role(s) of the native extracellular matrix. In the last few years, two naturally occurring polymers that are produced by deep-sea sponges, the biogenic polyphosphate (bio-polyP) and biogenic silica (bio-silica) have also been identified as promoting morphogenetic on both osteoblasts and osteoclasts. These polymers elicit cytokines that affect bone mineralization (hydroxyapatite formation). In this manner, bio-silica and bio-polyP cause an increased release of BMP-2, the key mediator activating the anabolic arm of the hydroxyapatite forming cells, and of RANKL. In addition, bio-polyP inhibits the progression of the pre-osteoclasts to functionally active osteoclasts. Based on these findings, new bioinspired strategies for the fabrication of bone biomimetic templates have been developed applying 3D-printing techniques. Finally, a strategy is outlined by which these two morphogenetically active polymers might be used to develop a novel functionally active polymer.
The Relationship between Lutein and Zeaxanthin Status and Body Fat
Authors: Bovier Emily , Lewis Richard , Hammond Billy
Published: March 2013

The objective of this project was to investigate the relationships between total and regional distribution of body fat and tissue lutein (L) and zeaxanthin (Z) status. Healthy men and women (N = 100; average age: 22.5 year, average BMI: 23.4 kg/m2) were evaluated. Total body and regional fat mass were assessed by dual-energy X-ray absorptiometry (Hologic Delphi A). Serum LZ was measured using reverse phase high-performance liquid chromatography, and retinal LZ (referred to as macular pigment optical density; MPOD) was measured using heterochromatic flicker photometry. Body fat percentage (total and regional) was inversely related to MPOD (p < 0.01) but no significant relationship was found for serum LZ. Higher body fat percentage, even within relatively healthy limits, is associated with lower tissue LZ status. The results indicate that adiposity may affect the nutritional state of the retina. Such links may be one of the reasons that obesity promotes age-related degenerative conditions of the retina.
An unusual case of isolated, serial metastases of gallbladder carcinoma involving the chest wall, axilla, breast and lung parenchyma
Authors: Jeyaraj Pamela , Sio Terence T. , Iott Matthew J.
Published: March 2013

In the English literature, only 9 cases of adenocarcinoma of the gallbladder with cutaneous metastasis have been reported so far. One case of multiple cutaneous metastases along with deposits in the breast tissue has been reported. We present a case of incidental metastatic gallbladder carcinoma with no intra-abdominal disease presenting as a series of four isolated cutaneous right chest wall, axillary nodal, breast, and pulmonary metastases following resection and adjuvant chemoradiation for her primary tumor. In spite of the metastatic disease coupled with the aggressive nature of the cancer, this patient reported that her energy level had returned to baseline with a good appetite and a stable weight indicating a good performance status and now is alive at 25 months since diagnosis. Her serially-presented, oligometastatic diseases were well-controlled by concurrent chemoradiotherapy and stereotactic radiation therapy. We report this case study because of its rarity and for the purpose of complementing current literature with an additional example of cutaneous metastasis from adenocarcinoma of the gallbladder.
A eurypterid from the lacustrine facies of the Early Devonian Campbellton Formation, New Brunswick, Canada
Authors: Miller Randall , Kennedy Kirsten , Gibling Martin
Published: March 2013

The Early Devonian Campbellton Formation in northern New Brunswick, Canada, yielded its first eurypterid fossils in 1881. Based on recent taxonomic work, all known specimens have been assigned to Pterygotus anglicus, a large pterygotid first described from Scotland. These previously discovered eurypterids are from the western exposure of the Campbellton Formation and are believed to have inhabited a coastal deltaic setting, along with a rich vertebrate assemblage that included cephalaspids, placoderms, acanthodians, and sharks. The single eurypterid abdominal fragment described here as cf. Parahughmilleria was found in beds near the eastern exposure of the formation from a lacustrine facies. These beds are from classic plant-rich localities of the Camp-bellton Formation and, in addition to plants, have yielded the oldest land-animal assemblage in North America.
The spectral radius in $\mathcal{C}_0(X)$-Banach algebras
Authors: Paravicini Walther
Published: March 2013

The spectral radius of an element of a

\mathcal{C}_0(X)

-Banach algebra can be calculated as the supremum of the spectral radii in the fibres. As a consequence, calculations in K-theory for such algebras can potentially be carried out fibrewise.
The Bost conjecture and proper Banach algebras
Authors: Paravicini Walther
Published: March 2013

For proper Banach algebra coefficients, the Bost assembly map is split surjective and the right-hand side of the conjecture does not depend on the choice of the unconditional completion involved. These results hold for a large class of unconditional completions.
Some ‘homological’ properties of the stable Higson corona
Authors: Willett Rufus
Published: March 2013

We establish certain ‘homological properties’ of the
stable Higson corona
used by Emerson and Meyer to study the Dirac-dual-Dirac approach to the Baum–Connes conjecture [5]. These are used to obtain explicit isomorphisms between the K-theory groups of stable Higson coronas, and the K-theory groups of certain geometrically defined boundaries. This is sufficient to give a simple proof of the strong Novikov conjecture for torsion-free hyperbolic groups and torsion-free groups acting properly and cocompactly on CAT(0) spaces, and also provides an input into an index theorem in single operator theory [15], [16].
Idempotent states on compact quantum groups and their classification on $\mathrm{U}_q(2)$, $\mathrm{SU}_q(2)$, and $\mathrm{SO}_q(3)$
Authors: Franz Uwe , Skalski Adam , Tomatsu Reiji
Published: March 2013

Unlike for locally compact groups, idempotent states on locally compact quantum groups do not necessarily arise as Haar states of compact quantum subgroups. We give a simple characterisation of those idempotent states on compact quantum groups that do arise as Haar states on quantum subgroups. We also show that all idempotent states on the quantum groups

\mathrm{U}_q(2)

,

\mathrm{SU}_q(2)

, and

\mathrm{SO}_q(3)

(

q \in (-1,0)\cup (0,1]

) arise in this manner and list the idempotent states on the compact quantum semigroups

\mathrm{U}_0(2)

,

\mathrm{SU}_0(2)

, and

\mathrm{SO}_0(3)

. In the Appendix we provide a short new proof of the coamenability of deformations of classical compact Lie groups based on their representation theory.
Combinatorial Dyson–Schwinger equations in noncommutative field theory
Authors: Tanasă Adrian , Kreimer Dirk
Published: March 2013

We introduce here the Hopf algebra structure describing the noncommutative renormalization of a recently introduced translation-invariant model on Moyal space. We define Hochschild one-cocyles

B_+^\gamma

which allows us to write down the combinatorial Dyson–Schwinger equations for noncommutative quantum field theory. One- and two-loops examples are explicitly worked out.
The Bost–Connes phase transition and unitary representations
Authors: Crisp Tyrone
Published: March 2013

We construct a family of unitary representations of the

ax+b

group

\mathbb{Q}\rtimes\mathbb{Q}_+^\times

. We show that this family of representations exhibits a “phase transition” analogous to that observed by Bost and Connes [2] and then explain how these representations are related to the equilibrium states of Bost and Connes.
Toward a New Algorithm for Nonlinear Fractional Differential Equations
Authors: Awawdeh Fadi , Abbasbandy S.
Published: March 2013

This paper is concerned with the development of an efficient algorithm for the analytic solutions of nonlinear fractional differential equations. The proposed algorithm Laplace homotopy analysis method (LHAM) is a combined form of the Laplace transform method with the homotopy analysis method. The biggest advantage the LHAM has over the existing standard analytical techniques is that it overcomes the difficulty arising in calculating complicated terms. Moreover, the solution procedure is easier, more effective and straightforward. Numerical examples are examined to demonstrate the accuracy and efficiency of the proposed algorithm.
Formigas de solo e de bromélias em uma área de Mata Atlântica, Ilha de Santa Catarina, sul do Brasil: Levantamento de espécies e novos registros
Authors: Rosumek Félix Baumgarten , Ulysséa Mônica Antunes , Lopes Benedito Cortês , Steiner Josefina , Zillikens Anne
Published: March 2013

A mirmecofauna em uma área de Mata Atlântica da Ilha de Santa Catarina foi inventariada utilizando métodos diversos para formigas de solo e de bromélias. Foram feitas amostragens mensais entre março de 2002 e agosto de 2004, utilizando o extrator de Winkler, armadilhas de interceptação e queda, além de coleta de bromélias. Foram encontradas 124 espécies, divididas em nove subfamílias e 33 gêneros. Os gêneros com maior riqueza foram Pheidole, Solenopsis, Crematogaster, Acromyrmex e Camponotus. Encontrou-se mais espécies no solo que nas bromélias, com 8% do total ocorrendo nos dois hábitats. Foram obtidos 11 registros novos para o estado de Santa Catarina e 20 para a região da Grande Florianópolis. Tais resultados estão relacionados com o uso de metodologias novas para a região, e mostram que a fauna de formigas desta ainda precisa ser mais bem estudada.
The magnitude and causes of uncertainty in global model simulations of cloud condensation nuclei
Authors: Lee L. A. , Pringle K. J. , Reddington C. L. , Mann G. W. , Stier P. , Spracklen D. V. , Pierce J. R. , Carslaw K. S.
Published: March 2013

Abstract. The global distribution of cloud condensation nuclei (CCN) is the fundamental quantity that determines how changes in aerosols affect climate through changes in cloud drop concentrations, cloud albedo and precipitation. Aerosol-cloud interaction effects are a major source of uncertainty in climate models so it is important to quantify the sources of uncertainty and thereby direct research efforts. However, the computational expense of global aerosol models has prevented a full statistical analysis of their outputs. Here we perform a variance-based analysis of a global 3-D aerosol microphysics model to quantify the magnitude and leading causes of parametric uncertainty in model-estimated present-day CCN concentrations. Twenty-eight model parameters covering essentially all important aerosol processes, emissions and representation of aerosol size distributions were defined based on expert elicitation. An uncertainty analysis was then performed based on a Monte Carlo-type sampling of an emulator built for each monthly-mean model grid cell from an ensemble of 168 one-year model simulations covering the uncertainty space of the 28 parameters. The standard deviation around the mean CCN varies globally between about ±30% of the mean over some marine regions to ±40–100% over most land areas and high latitudes. The results imply that aerosol processes and emissions are likely to be a significant source of uncertainty in model simulations of aerosol-cloud effects on climate. Variance decomposition enables the importance of the parameters for CCN uncertainty to be quantified and ranked from local to global scales. Among the most important contributors to CCN uncertainty are the sizes of emitted primary particles, including carbonaceous combustion particles from wildfires, biomass burning and fossil fuel use, as well as sulphate particles formed on sub-grid scales. Emissions of carbonaceous combustion particles affect CCN uncertainty more than sulphur emissions. Aerosol emission-related parameters dominate the uncertainty close to sources, while uncertainty in aerosol microphysical processes becomes increasingly important in remote regions, being dominated by deposition and aerosol sulphate formation during cloud-processing. Most of the 28 parameters are important for CCN uncertainty somewhere on the globe. The results lead to several recommendations for research that would result in improved modelling of cloud-active aerosol on a global scale.
Temperature dependence of coastal wetland ecosystem respiration confounded by tidal activities: a temporal perspective
Authors: Xie X. , Zhang M.-Q. , Zhao B. , Guo H.-Q.
Published: March 2013

Abstract. Variations of temperature and hydrological conditions result in the fluctuation of ecosystem respiration (ER). Temperature sensitivity is widely used to describe ER-temperature relationship, but hydrological condition with similar dynamics as temperature could cause confounding effect. Many researchers have made comparisons between long-term and short-term models to show the confounding effect. However, how temperature sensitivity is confounded by hydrological condition in different time scales remains unknown. In this study, data from two coastal wetland sites were used. By comparing the variations of temperature and tidal influence at three time scales (monthly, seasonal and half-yearly), we found that: (1) the co-variation of temperature and other environmental factors accounted for the long-term confounding effect, and (2) the small variances of temperature in short time scale explained the short-term confounding effect. As a result of the long-term confounding effect, greater system errors were introduced in long-term model than short-term did. As the temperature sensitivity derived from long-term "ignored" the alternation of main driving factor of ER, temperature influence on ER was overestimated while the tidal influence was underestimated. Tidal activities had great influences on ER when the variances of temperature were small. If short-term model without tidal effect was applied, short-term confounding effect was inevitable. Compared to the long-term model (half-yearly), short-term model (monthly without tidal effect) performed better that helped reduce the long-term confounding effect, and integrating a proper secondary factor like tide would further reduce the short-term confounding effect.
Terpenoid emissions from fully grown East Siberian Larix cajanderi trees
Authors: Kajos M. K. , Hakola H. , Holst T. , Nieminen T. , Tarvainen V. , Maximov T. , Petäjä T. , Arneth A. , Rinne J.
Published: March 2013

Abstract. While emissions of many volatile compounds, such as terpenoids, have been studied quite intensively in North American and Scandinavian boreal forests, the vast Siberian boreal forests have remained largely unexplored by experimental emission studies. In this study the shoot scale terpenoid emission rates from mature Larix cajanderi trees growing in their natural habitat in Eastern Siberia were measured. Dynamic flow-through enclosure technique was applied for adsorbent sampling (Tenax-TA and Carbopack-B used as adsorbents), and the samples were analysed offline with a gas chromatograph. The emissions were dominated by monoterpenes, which constituted between 61 and 92% of the total emission. About half of the monoterpene emissions comprised of Δ3-carene; α- and β-pinene had significant emissions as well. Linalool emissions were also substantial, especially in June. Sesquiterpenes accounted for less than 3% and isoprene less than 1% of the total emissions. Based on the measured emission rates, the relative atmospheric concentration of each compound was estimated. Monoterpenes were the species with the highest relative concentration, while linalool and sesquiterpenes had a notably smaller contribution to the estimated atmospheric concentration than to the emission rates. Temperature dependent pool algorithm with a constant β (0.09 °C−1 for monoterpenes and 0.143 °C−1 for sesquiterpenes) was used to normalize the measured emission data. For monoterpenes the emission potential varied between 0.5–18.5 μg gdw−1 h−1 and for sesquiterpenes between 0.02 and 0.4 μg gdw−1 h−1.
Technical Note: Dissolved organic matter fluorescence – a finite mixture approach to deconvolve excitation-emission matrices
Authors: Butturini A. , Ejarque E.
Published: March 2013

Abstract. The analysis of the shape of excitation-emission matrices (EEMs) is a relevant tool for exploring the origin, transport and fate of dissolved organic matter (DOM) in aquatic ecosystems. Within this context, the decomposition of EEMs is acquiring a notable relevance. A simple mathematical algorithm that automatically deconvolves single EEM is described, creating new possibilities for the comparison of DOM fluorescence properties and EEMs that are very different from each other. A mixture model approach is adopted to decompose complex surfaces into sub-peaks. The laplacian operator and the Nelder–Mead optimization algorithm are implemented to individuate and automatically locate potential peaks in the EEM landscape. A small heterogeneous data set of 21 EEMs from a human-impacted Mediterranean river is used to describe the model application and to illustrate a strategy that optimises the search for the optimal output.
Iron fluxes to Talos Dome, Antarctica, over the past 200 kyr
Authors: Vallelonga P. , Barbante C. , Cozzi G. , Gabrieli J. , Schüpbach S. , Spolaor A. , Turetta C.
Published: March 2013

Abstract. Atmospheric fluxes of iron (Fe) over the past 200 kyr are reported for the coastal Antarctic Talos Dome ice core, based on acid leachable Fe concentrations. Fluxes of Fe to Talos Dome were consistently greater than those at Dome C, with the greatest difference observed during interglacial climates. We observe different Fe flux trends at Dome C and Talos Dome during the deglaciation and early Holocene, attributed to a combination of deglacial activation of dust sources local to Talos Dome and the reorganisation of atmospheric transport pathways with the retreat of the Ross Sea ice shelf. This supports similar findings based on dust particle sizes and fluxes and Rare Earth Element fluxes. We show that Ca and Fe should not be used as quantitative proxies for mineral dust, as they all demonstrate different deglacial trends at Talos Dome and Dome C. Considering that a 20 ppmv decrease in atmospheric CO2 at the coldest part of the last glacial maximum occurs contemporaneously with the period of greatest Fe and dust flux to Antarctica, we confirm that the maximum contribution of aeolian dust deposition to Southern Ocean sequestration of atmospheric CO2 is approximately 20 ppmv.
Atmospheric dissolved iron deposition to the global oceans: effects of oxalate-promoted Fe dissolution, photochemical redox cycling, and dust mineralogy
Authors: Johnson M. S. , Meskhidze N.
Published: March 2013

Abstract. Mineral dust deposition is suggested to be a significant atmospheric supply pathway of bioavailable iron (Fe) to Fe-depleted surface oceans. In this study, mineral dust and dissolved Fe (Fed) deposition rates are predicted for March 2009 to February 2010 using the 3-D chemical transport model GEOS-Chem implemented with a comprehensive dust-Fe dissolution scheme. The model simulates Fed production during the atmospheric transport of mineral dust taking into account inorganic and organic (oxalate)-promoted Fe dissolution processes, photochemical redox cycling between ferric (Fe(III)) and ferrous (Fe(II)) forms of Fe, dissolution of three different Fe-containing minerals (hematite, goethite, and aluminosilicates), and detailed mineralogy of wind-blown dust from the major desert regions. Our calculations suggest that during the yearlong simulation ~ 0.26 Tg (1 Tg = 1012 g) of Fed was deposited to global oceanic regions. Compared to simulations only taking into account proton-promoted Fe dissolution, the addition of oxalate to the dust-Fe mobilization scheme increased total annual model-predicted Fed deposition to global oceanic regions by ~ 75%. The implementation of Fe(II)/Fe(III) photochemical redox cycling in the model allows for the distinction between different oxidation states of deposited Fed. Our calculations suggest that during the daytime, large fractions of Fed deposited to the global oceans is likely to be in Fe(II) form, while nocturnal fluxes of Fed are largely in Fe(III) form. Model simulations also show that atmospheric fluxes of Fed can be strongly influenced by the mineralogy of Fe-containing compounds. This study indicates that Fed deposition to the oceans is controlled by total dust-Fe mass concentrations, mineralogy, the surface area of dust particles, atmospheric chemical composition, cloud processing, and meteorological parameters and exhibits complex and spatiotemporally variable patterns. Our study suggests that the explicit model representation of individual processes leading to Fed production within mineral dust are needed to improve the understanding of the atmospheric Fe cycle, and quantify the effect of dust-Fe on ocean biological productivity, carbon cycle, and climate.
MEDSLIK-II, a Lagrangian marine oil spill model for short-term forecasting – Part 2: Numerical simulations and validations
Authors: De Dominicis M. , Pinardi N. , Zodiatis G. , Archetti R.
Published: March 2013

Abstract. In this paper we use MEDSLIK-II, a Lagrangian marine oil spill model described in Part 1 of this paper (De Dominicis et al., 2013), to simulate oil slick transport and transformation processes for realistic oceanic cases where satellite or drifting buoys data are available for verification. The model is coupled with operational oceanographic currents, atmospheric analyses winds and remote-sensing data for initialization. The sensitivity of the oil spill simulations to several model parameterizations is analyzed and the results are validated using surface drifters and SAR (Synthetic Aperture Radar) images in different regions of the Mediterranean Sea. It is found that the forecast skill of Lagrangian trajectories largely depends on the accuracy of the Eulerian ocean currents: the operational models give useful estimates of currents, but high-frequency (hourly) and high spatial resolution is required, and the Stokes drift velocity has to be often added, especially in coastal areas. From a numerical point of view, it is found that a realistic oil concentration reconstruction is obtained using an oil tracer grid resolution of about 100 m, with at least 100 000 Lagrangian particles. Moreover, sensitivity experiments to uncertain model parameters show that the knowledge of oil type and slick thickness are, among all the others, key model parameters affecting the simulation results. Considering acceptable for the simulated trajectories a maximum spatial error of the order of three times the horizontal resolution of the Eulerian ocean currents, the predictability skill for particle trajectories is from 1 to 2.5 days depending on the specific current regime. This suggests that re-initialization of the simulations is required every day.
La preceptiva sobre la narratio en los rétores latinos
Authors: Olmos Gómez Paula
Published: March 2013

This paper reviews and comments different texts containing the theories and doctrines developed by ancient Latin rhetoricians on the argumentative and persuasive characteristics of narrative discourse as opposed to explicitly argumentative discourse. As stated in the introduction and the conclusion, these theories became a source of inspiration to Rodophus Agricola’s study of the distinction expositio/argumentatio, a particularly interesting piece of his dialectic which may still be theoretically and philosophically valuable. We will review texts on narratio, most especially legal narratio, by Cicero (1st c. BCE), Quintilian (1st c.), Julius Severianus (2nd c.), Fortunatianus, Marius Víctorinus, Gaius Julius Víctor, Sulpicius Víctor (4th c.) and Martianus Capella (5th c.).
Desde el umbral de las palabras: sobre lo sublime a partir de Pseudo-Longino
Authors: Acosta López María del Rosario
Published: March 2013

The category of the sublime, which has been amply discussed but not well defined and which is a central category to modern and contemporary aesthetics, was first exposed in detail in a treatise on rhetoric dating from the first century, AD. This document, written by an anonymous author – probably a Pseudo-Longinus, a Greek exiled from Rome – would become, after its translation into French by Bileau (1674), a determinant starting point for the introduction to modern aesthetic reflections on the experience of the sublime. This paper presents a journey that seeks to analyze the rhetoric treatise “On the Sublime [Peri hypsos]” by Pseudo-Longinus, highlighting those places where the sublime, in its most classical presentation, is already related to some of the most interesting traits of its rise as a modern aesthetic category, foreshadowing the twist it will acquire in contemporary interpretation. The motivation is to corroborate, from a specific interpretative reading of Pseudo-Longinus’ text, how the path towards aesthetics originates in classical rhetoric and to show that the history of aesthetics has inherited a question that has particular resonance in contemporary thought: the question surrounding how language, image, and work of art can only be presented or represented in the vague limit between what is shown and what is hidden, making evident, and transforming into experience, the limits of their own communicability.
Charge‐Tunable Autoclaved Silk‐Tropoelastin Protein Alloys That Control Neuron Cell Responses
Authors: Hu Xiao , Tang‐Schomer Min D. , Huang Wenwen , Xia Xiao‐Xia , Weiss Anthony S. , Kaplan David L.
Published: March 2013

Tunable protein composites are important for constructing extracellular matrix mimics of human nerve tissues with control of charge, structural, and mechanical properties. Molecular interaction mechanisms between silk fibroin protein and recombinant human tropoelastin, based on charge, are utilized to generate a new group of multifunctional protein alloys with different net charges. These new biomaterials are then utilized as a biomaterial platform to control neuron cell response. With a +38 net charge in water, tropoelastin molecules provide extraordinary elasticity and selective interactions with cell surface integrins. In contrast, negatively charged silk fibroin protein (net charge −36) provides remarkable toughness and stiffness with morphologic stability in material formats via autoclaving‐induced beta‐sheet crystal physical crosslinks. The combination of these properties in alloy format extends the versatility of both structural proteins, providing a new biocompatible, biodegradable, and charge‐tunable biomaterial platform for neural repair. The data point to these protein alloys as an alternative to commonly used charged synthetic polymers, particularly with regard to the versatility of material formats (e.g., gels, sponges, films, fibers). The results also provide a practical example of physically designed protein materials with control of net charge to direct biological outcomes, in this case for neuronal tissue engineering.
Biomimetic Structural Electrochemistry from Conducting Polymers: Processes, Charges, and Energies. Coulovoltammetric Results from Films on Metals Revisited
Authors: Otero Toribio F. , Alfaro Mercedes , Martinez Venancio , Perez Maria A. , Martinez Jose G.
Published: March 2013

Oxidation/reduction reactions in films of conducting polymers exchanging anions and solvent during reactions are revisited here and explored by voltammetric and coulovoltammetric results using Pt electrodes coated with films of different polymers, in different solvents and salts. The reactions induce molecular (conformational) and macroscopic (relaxation, swelling, shrinking, and compaction) structural changes. Coulovoltammetric loops constitute a direct graphical tool to identify, separate, and quantify the structural components of the reversible film reactions together the potential domains and the charges involved in irreversible reactions. Any abrupt slope variation is related to abrupt changes of the reaction rate associated with each of the structural induced processes. Charges, energies, and characteristic potentials for any of the structural or irreversible process are obtained. Reversible film reactions are present from –1.5 to 0.35 V versus Ag/AgCl, overlapping the irreversible hydrogen evolution at the metal/polymer interface below –1.1 V. Structural reduction energies are higher than structural oxidation energies and structural changes are energetically asymmetric. 3D reactive structural memories are envisaged stepping up storage density by orders of magnitude. Conducting polymers are 3D structural gel reactors at the polymer chain level: large anions in solution cannot penetrate inside the film. Composition changes and structural processes mimic intracellular matrix (ICM) biological reactions.
Bulk Manufacture of Concentrated Oxygen Gas‐Filled Microparticles for Intravenous Oxygen Delivery
Authors: Kheir John N. , Polizzotti Brian D. , Thomson Lindsay M. , O'Connell Daniel W. , Black Katherine J. , Lee Robert W. , Wilking James N. , Graham Adam C. , Bell David C. , McGowan Francis X.
Published: March 2013

Self‐assembling, concentrated, lipid‐based oxygen microparticles (LOMs) have been developed to administer oxygen gas when injected intravenously, preventing organ injury and death from systemic hypoxemia in animal models. Distinct from blood substitutes, LOMs are a one‐way oxygen carrier designed to rescue patients who experience life‐threatening hypoxemia, as caused by airway obstruction or severe lung injury. Here, we describe methods to manufacture large quantities of LOMs using an in‐line, recycling, high‐shear homogenizer, which can create up to 4 liters of microparticle emulsion in 10 minutes, with particles containing a median diameter of 0.93 microns and 60 volume% of gas phase. Using this process, we screen 30 combinations of commonly used excipients for their ability to form stable LOMs. LOMs composed of DSPC and cholesterol in a 1:1 molar ratio are stable for a 100 day observation period, and the number of particles exceeding 10 microns in diameter does not increase over time. When mixed with blood in vitro, LOMs fully oxygenate blood within 3.95 seconds of contact, and do not cause hemolysis or complement activation. LOMs can be manufactured in bulk by high shear homogenization, and appear to have a stability and size profile which merit further testing.
Genetic characterization of central Mediterranean stocks of the loggerhead turtle (Caretta caretta) using mitochondrial and nuclear markers, and conservation implications
Authors: Garofalo Luisa , Mastrogiacomo Angela , Casale Paolo , Carlini Rossella , Eleni Claudia , Freggi Daniela , Gelli Donatella , Knittweis Leyla , Mifsud Carmen , Mingozzi Toni , Novarini Nicola , Scaravelli Dino , Scillitani Giovanni , Oliverio Marco , Novelletto Andrea
Published: March 2013

In migratory species female‐ and male‐mediated gene flow are important for defining relevant Management Units, and for evaluating connectivity between these and their respective foraging grounds.

The stock composition at five Mediterranean foraging areas was investigated by analysing variation in the mitochondrial D‐loop and six microsatellite loci in a sample of 268 loggerhead turtles (Caretta caretta) stranded or accidentally caught by fisheries. This involved a comprehensive Mixed Stock Analysis which considers also recent data from major rookeries in Libya and Turkey, and the generation of a standardized nomenclature of allele sizes at the microsatellite loci.

The results indicate:

that the north Adriatic, the Tunisian continental shelf, the waters around Malta and the Italian Ionian Sea represent important areas for the conservation of rookeries in Greece, Libya and Turkey, respectively;

that waters off the Italian peninsula and the islands of Lampedusa and Malta are mainly inhabited by individuals of Mediterranean origin, with a major contribution from the nearest and largest colonies, while Atlantic turtles are restricted to the western areas;

that specific migratory routes exist from rookeries to foraging grounds;

a poor bi‐parental genetic structuring, which suggests a high male‐mediated gene flow in the Mediterranean;

mixing of small turtles in waters distant from natal rookeries, and recovery of structuring for large‐sized individuals; and

that uncommon mtDNA haplotypes are more powerful markers than microsatellite alleles in assessing an individual's origin, owing to their higher geographic specificity.

Copyright © 2013 John Wiley & Sons, Ltd.
Scale‐up and intensification of (S)‐1‐(2‐chlorophenyl)ethanol bioproduction: Economic evaluation of whole cell‐catalyzed reduction of o‐Chloroacetophenone
Authors: Eixelsberger Thomas , Woodley John M. , Nidetzky Bernd , Kratzer Regina
Published: March 2013

Escherichia coli cells co‐expressing genes coding for Candida tenuis xylose reductase and Candida boidinii formate dehydrogenase were used for the bioreduction of o‐chloroacetophenone with in situ coenzyme recycling. The product, (S)‐1‐(2‐chlorophenyl)ethanol, is a key chiral intermediate in the synthesis of polo‐like kinase 1 inhibitors, a new class of chemotherapeutic drugs. Production of the alcohol in multi‐gram scale requires intensification and scale‐up of the biocatalyst production, biotransformation, and downstream processing. Cell cultivation in a 6.9‐L bioreactor led to a more than tenfold increase in cell concentration compared to shaken flask cultivation. The resultant cells were used in conversions of 300 mM substrate to (S)‐1‐(2‐chlorophenyl)ethanol (e.e. >99.9%) in high yield (96%). Results obtained in a reaction volume of 500 mL were identical to biotransformations carried out in 1 mL (analytical) and 15 mL (preparative) scale. Optimization of product isolation based on hexane extraction yielded 86% isolated product. Biotransformation and extraction were accomplished in a stirred tank reactor equipped with pH and temperature control. The developed process lowered production costs by 80% and enabled (S)‐1‐(2‐chlorophenyl)ethanol production within previously defined economic boundaries. A simple and efficient way to synthesize (S)‐1‐(2‐chlorophenyl)ethanol in an isolated amount of 20 g product per reaction batch was demonstrated. Biotechnol. Bioeng. 2013; 110: 2311–2315. © 2013 Wiley Periodicals, Inc.
Surface and mechanical analysis of explanted Poly Implant Prosthèse silicone breast implants
Authors: Yildirimer L , Seifalian A M , Butler P E
Published: March 2013

Background

The recent events surrounding Poly Implant Prosthèse (PIP) breast implants have renewed the debate about the safety profile of silicone implants. The intentional use of industrial-grade instead of certified medical-grade silicone is thought to be responsible for reportedly higher frequencies of implant rupture in vivo. The differences in mechanical and viscoelastic properties between PIP and medical-grade silicone implant shells were investigated. Surface characterization of shells and gels was carried out to determine structural changes occurring after implantation.

Methods

Breast implants were obtained from women at the Royal Free Hospital (London, UK). PIP implants were compared with medical-grade control silicone implants. Tensile strength, tear resistance and elongation at break were assessed using a tensile tester. Surfaces were analysed using attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy. Spearman correlation analyses and Kruskal–Wallis one-way statistical tests were performed for mechanical data.

Results

There were 18 PIP and four medical-grade silicone implants. PIP silicone shells had significantly weaker mechanical strength than control shells (P < 0·009). There were negative correlations between mechanical properties of PIP shells and implantation times, indicative of deterioration of PIP shells over time in vivo (rs = –0·75, P = 0·009 for tensile strength; rs = –0·76, P = 0·001 for maximal strain). Comparison of ATR-FTIR spectra of PIP and control silicones demonstrated changes in material characteristics during the period of implantation suggestive of time-dependent bond breakage and degradation of the material.

Conclusion

This study demonstrated an increased weakness of PIP shells with time and therefore supports the argument for prophylactic removal of PIP breast implants.
A comparison of the femoral and radial crossover techniques for vascular access management in transcatheter aortic valve implantation: The milan experience
Authors: Curran Helen , Chieffo Alaide , Buchanan Gill Louise , Bernelli Chiara , Montorfano Matteo , Maisano Francesco , Latib Azeem , Maccagni Davide , Carlino Mauro , Figini Filippo , Cioni Micaela , Canna Giovanni La , Covello Remo Daniel , Franco Annalisa , Gerli Chiara , Alfieri Ottavio , Colombo Antonio
Published: March 2013

Objective

To compare radial and femoral crossover techniques (CT) for vascular access management in transcatheter aortic valve implantation (TAVI).

Background

Femoral crossover for controlled angiography and balloon inflation of the therapeutic access site to facilitate safe vascular closure is beneficial but technically challenging in patients with complex femoral anatomy. An alternative approach should be available.

Methods

Between June 2011 and March 2012, 41 transfemoral TAVI patients receiving the femoral CT were compared to 46 transfemoral TAVI patients receiving the radial CT. Outcomes were 30‐day valve academic research consortium (VARC) endpoints.

Results

Patients undergoing the radial CT received higher median contrast volumes (150 interquartile range [IQR]: 105–180 vs. 111 IQR: 90–139 ml; P = 0.025) but procedural radiation dose and fluoroscopy times were comparable. Thirty day all cause and cardiovascular death were similar between radial and femoral CT groups (respectively 2.4% vs. 7.9%, P = 0.258 and 0% vs. 7.9%, P = 0.063). There were no differences in major vascular complications (4.3% vs. 7.3%, P = 0.553), life threatening or major bleeding events (respectively 9.1% vs. 19.5%, P = 0.168 and 13.6% vs. 22%, P = 0.315).

Conclusion

In TAVI cases with unfavorable contralateral femoral anatomy, radial CT for vascular access management is a reasonable alternative to the femoral CT. © 2013 Wiley Periodicals, Inc.
Stent exteriorization facilitates surgical repair for large‐bore sheath complications
Authors: George Isaac , Shrikhande Gautam , Williams Mathew R.
Published: March 2013

Endovascular therapy for peripheral vascular and valvular disease has rapidly expanded and yet also produced new challenges for vascular access and closure. Current generation thoracic endograft (TEVAR) outer diameter sheath sizes range from 18 to 25 French, and the options for vascular access closure include off‐label use of a closure device versus surgical cutdown. We describe a patient with a complex, post‐dissection, descending aortic aneurysm who required TEVAR and had a vascular access complication repaired with stent exteriorization with open repair. © 2013 Wiley Periodicals, Inc.
ChemInform Abstract: Alkyne and Alkene Insertion into Metal—Heteroatom and Metal—Hydrogen Bonds. The Key Stages of a Hydrofunctionalization Process
Authors: Ananikov Valentine P. , Beletskaya Irina P.
Published: March 2013

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