bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of pyridine treatment on phase Q: Orgueil and Allende
Authors: MATSUDA Jun‐ichi , AMARI Sachiko , MORISHITA Kazuhiko , NAGASHIMA Kana , NARA Masayuki
Published: October 2010

Abstract–

Marrocchi et al. (2005) reported that low‐temperature fractions of heavy noble gases were largely removed upon pyridine treatment of the Orgueil CI meteorite. As pyridine is known to induce the swelling of the macromolecular network of organic matter, they concluded that the low‐temperature phase Q is macromolecular organic carbon. However, Busemann et al. (2008) showed that pyridine had no significant effect on the noble gas contents for other very primitive meteorites, such as CM and CR. Therefore, we prepared an HF–HCl residue and the pyridine‐treated residue of Orgueil, and re‐examined the results of Marrocchi et al. (2005) by analyzing all noble gases. We confirmed that heavy noble gases are surely removed by the pyridine treatment, but the degree of the loss of heavy noble gases is generally small, and is even smaller for the lighter noble gases. Furthermore, we could not observe the evidence of Xe isotopic ratios by removing only phase Q after the pyridine treatment. We further prepared the HF–HCl residue and the pyridine‐treated residue of the Allende CV3 meteorite and performed noble gas analyses. For Allende, there is no significant change in the elemental abundances after the pyridine treatment. These results suggest that only Orgueil is special, and it is likely that the gas loss of the Orgueil residue is due to the loss of some kind of organic matter that was formed and that adsorbed the fractionated Q and HL gases during the aqueous alteration within the parent body of Orgueil.
NGOs' Strategies and the Challenge of Development and Democracy in Bangladesh
Authors: Kabeer Naila , Mahmud Simeen , Isaza Castro Jairo Guillermo
Published: October 2010

Recent research Bangladesh has come to embody an interesting paradox. On the one hand, it has experienced rising rates of growth, a slow but steady decline in poverty and impressive progress in terms of social development, outperforming some of its richer neighbours on a number of Millennium Development Goals. On the other hand, it has an abysmal record on governance and was ranked as the world's most corrupt country for five consecutive years by Transparency International. There is an emerging view that the country's extremely active development NGO sector has contributed to some of the more positive achievements. The question that this paper sets out to address is why these organisations have not made an equivalent contribution on the governance front. The paper argues that while Bangladesh is reported to have more NGOs per capita than other developing countries, those organisations have gradually abandoned social mobilising and collective action strategies for a narrower focus on service delivery and microcredit provision. Our research with the members of six organisations that straddle the continuum between microfinance and social mobilisation suggests that the specific developmental strategies of these membership‐based groups do indeed have consequences for both development and democracy in the country.
Adaptive Social Protection: Mapping the Evidence and Policy Context in the Agriculture Sector in South Asia
Authors: Arnall Alex , Oswald Katy , Davies Mark , Mitchell Tom , Coirolo Cristina
Published: October 2010

An aim of government and the international community is to respond to global processes and crises through a range of policy and practical approaches that help limit damage from shocks and stresses. Three approaches to vulnerability reduction that have become particularly prominent in recent years are social protection (SP), disaster risk reduction (DRR) and climate change adaptation (CCA). Although these approaches have much in common, they have developed separately over the last two decades. However, given the increasingly complex and interlinked array of risks that poor and vulnerable people face, it is likely that they will not be sufficient in the long run if they continue to be applied in isolation from one another.

In recognition of this challenge, the concept of Adaptive Social Protection (ASP) has been developed. ASP refers to a series of measures which aims to build resilience of the poorest and most vulnerable people to climate change by combining elements of SP, DRR and CCA in programmes and projects. The aim of this paper is to provide an initial assessment of the ways in which these elements are being brought together in development policy and practice. It does this by conducting a meta‐analysis of 124 agricultural programmes implemented in five countries in south Asia. These are Afghanistan, Bangladesh, India, Nepal and Pakistan.

The findings show that full integration of SP, DRR and CCA is relatively limited in south Asia, although there has been significant progress in combining SP and DRR in the last ten years. Projects that combine elements of SP, DRR and CCA tend to emphasise broad poverty and vulnerability reduction goals relative to those that do not. Such approaches can provide valuable lessons and insights for the promotion of climate resilient livelihoods amongst policymakers and practitioners.
PiggyBac
Transposon Mutagenesis: A Tool for Cancer Gene Discovery in Mice
Authors: Rad Roland , Rad Lena , Wang Wei , Cadinanos Juan , Vassiliou George , Rice Stephen , Campos Lia S. , Yusa Kosuke , Banerjee Ruby , Li Meng Amy , de la Rosa Jorge , Strong Alexander , Lu Dong , Ellis Peter , Conte Nathalie , Yang Fang Tang , Liu Pentao , Bradley Allan
Published: October 2010

Piggybacking on Cancer Genes

Transposons are mobile segments of DNA that can insert in or near important genes to cause mutations that disrupt gene function.

Rad
et al.

(p.
1104
, published online 14 October) adapted a mutagenic transposon called Piggybac, originally derived from a moth, into a tool for discovery of cancer-causing genes in mice. Mobilization of Piggybac in mice was associated with the development of leukemias and solid tumors. In many instances the causative mutations, which were identified by mapping the Piggybac integration sites, were within genes not previously implicated in cancer.
Broken-Symmetry States in Doubly Gated Suspended Bilayer Graphene
Authors: Weitz R. T. , Allen M. T. , Feldman B. E. , Martin J. , Yacoby A.
Published: October 2010

Broken Symmetries

Bilayer graphene samples are expected exhibit quantum Hall states that are ferromagnetic with different types of spin ordering.

Weitz
et al.

(p.
812
, published online 14 October) studied the conductance of high-quality suspended bilayer graphene samples. They used an applied perpendicular electric field to induce transitions between the different broken-symmetry states that appear at low carrier densities and deduced their order parameters. These states appeared in both the absence of a magnetic field, as well as in the presence of a symmetry-breaking magnetic field. They also showed that, even in absence of both an applied magnetic or electric field, the bilayer exhibits an energy gap, which indicates that electron-electron interactions contribute to the band structure.
A Low-Magnetic-Field Soft Gamma Repeater
Authors: Rea N. , Esposito P. , Turolla R. , Israel G. L. , Zane S. , Stella L. , Mereghetti S. , Tiengo A. , Götz D. , Göğüş E. , Kouveliotou C.
Published: October 2010

Odd Magnetar

Magnetars are neutron stars that are widely thought to be powered by extremely high magnetic fields. Using data from three different x-ray observatories,

Rea
et al.

(p.
944
, published online 14 October) show that a previously known magnetar has a magnetic field that is much smaller than those of other magnetars. A strong magnetic field is thus not a necessary requirement for a neutron star to show magnetar-like behavior, implying that this population is wider than was previously thought.
Limited lymph-node recovery based on lymph-node localisation is sufficient for accurate staging: Table 1
Authors: Cserni Gábor , Bori Rita , Sejben István
Published: October 2010

Aims

To assess the reliability of nodal staging in colorectal carcinomas (CRCs) when only lymph nodes close to the tumour are recovered and examined histologically.

Methods

Lymph nodes from CRC resection specimens were recovered into two fractions: one from around the tumour and the 3 cm sidelong bowel segment associated with it in the proximal and distal directions, and another from the remaining part of the resection specimen.

Results

Of the 762 CRCs (239 right colon, 251 left colon, 257 rectum, 15 unspecified localisation) there were 393 node-negative and 369 node-positive cases. The median number of LNs examined was 18. The assessment of the LNs located in the close fraction (median 13) yielded an adequate qualitative nodal status in 756 patients (99.2%). In four cases (two rectal and two right colic), no LN metastases could be identified in the close-fraction lymph nodes, but nodes from the distant fraction contained metastases. Of the node-positive carcinomas which had at least one positive lymph node in the close fraction, 203 belonged to the pN1 category and 162 to the pN2 category of the Tumour Node Metastasis staging system. Only 14 cases (10 rectal, two right and two left colic tumours) were misclassified as pN1 (on the basis of lymph nodes recovered from the close fraction) although they were of the pN2 category.

Conclusions

In general, nodal status of CRCs may be adequately assessed by examining the lymph nodes from the close fraction around the tumour and the 3 cm sidelong bowel segment in both directions.
Lymphatic vessel density and its prognostic value in stage I colorectal carcinoma
Authors: Barresi V , Reggiani-Bonetti L , Di Gregorio C , Ponz De Leon M , Barresi G
Published: October 2010

Aims

The assessment of lymphatic vessel density (LVD) has been suggested as a tool to determine the metastatic risk of neoplasias. On this premise, the authors aimed to verify whether progression risk of stage I colorectal cancer may be related to LVD. The authors also evaluated and correlated vascular endothelial growth factor (VEGF)-A expression with LVD revealed in the same cases in order to investigate its potential lymphangiogenic role in the early stage colorectal cancer.

Methods

LVD and VEGF immunoexpression were analysed and compared in series of 29 stage I surgically resected colorectal carcinomas obtained from patients showing disease progression and in a cohort of 23 stage I colorectal cancers from patients with no evidence of disease progression. The prognostic value of LVD and of VEGF expression on the progression-free survival to colorectal cancer was investigated.

Results

A high density of peritumoural lymphatics (P-LVD) was significantly associated with high VEGF expression and disease progression. Moreover, high P-LVD and high VEGF expression were significant negative prognostic parameters associated with a shorter disease-free interval in stage I colorectal cancer.

Conclusions

If our findings are further confirmed in other studies, the assessment of P-LVD on surgical specimens might be used as a tool to identify patients with stage I colorectal cancer at higher risk of progression in order to submit them to adjuvant therapies. Since P-LVD seems to show a VEGF-A mediated regulation in stage I colorectal cancer, therapies targeting this factor might be exploited to reduce lymphangiogenesis and the progression risk of this neoplasia.
European field study of the efficacy and safety of the novel anthelmintic monepantel in sheep
Authors: Jones M. D. , Hunter R. P. , Dobson D. P. , Reymond N. , Strehlau G. A. , Kubacki P. , Tranchard E. S. N. , Walters M. E.
Published: October 2010

During 2007, a large‐scale controlled, multicentre, blinded and randomised field study was conducted in Scotland, England and France to assess the efficacy and safety of monepantel, the first molecule to be developed from the recently discovered amino‐acetonitrile derivatives class of anthelmintics, in sheep. Monepantel was administered orally, at a minimum dose of 2.5 mg/kg bodyweight, for the control of gastrointestinal nematodes in sheep maintained at pasture in a range of commercial production systems. Efficacy was measured by faecal egg count (FEC) reduction tests seven days after treatment and was demonstrated to be over 98 per cent against mixed‐genus infections. The reduction in FEC of monepantel‐treated sheep was statistically significantly greater than in untreated control sheep (P<0.0001). The efficacy of monepantel against mixed‐genus natural field infections of the major gastrointestinal nematodes was in agreement with similar studies conducted in Australia and New Zealand. There were no treatment‐related adverse events during the study, which included the use of a range of concomitant treatments.
Diagnosis of feline polycystic kidney disease by a combination of ultrasonographic examination and PKD1 gene analysis
Authors: Lee Y‐J. , Chen H‐Y. , Hsu W‐L. , Ou C‐M. , Wong M‐L.
Published: October 2010

Persian‐related and non‐Persian‐related cats were examined by ultrasonography and/or molecular testing to determine the prevalence of feline polycystic kidney disease (PKD) and the presence of a PKD1 gene mutation. PCR was used to amplify exon 29 of the PKD1 gene using genomic DNA extracted from blood samples, and the PCR products were analysed by direct DNA sequencing. Among the 111 cats included in the study, 54 were examined by both ultrasonography and gene testing for a point mutation in exon 29 of the PKD1 gene. The prevalence of PKD diagnosed by ultrasonography was 25.9 per cent in all the cats and 24.2 per cent in Persian‐related cats. The prevalence of the transversion mutation in exon 29 of the PKD1 gene was 13.5 per cent in all cats and 15.7 per cent in Persian‐related cats. Three cats that were diagnosed with PKD by ultrasonography did not have the mutation within exon 29. Nucleotide analysis of exon 29 indicated that male cats had a higher point mutation rate than female cats.
EXACT SOLUTIONS OF DIRAC EQUATION FOR A NEW SPHERICALLY ASYMMETRICAL SINGULAR OSCILLATOR
Authors: SUN GUO-HUA , DONG SHI-HAI
Published: October 2010

In this work we solve the Dirac equation by constructing the exact bound state solutions for a mixing of scalar and vector spherically asymmetrical singular oscillators. This is done provided that the vector potential is equal to the scalar potential. The spinor wave functions and bound state energy levels are presented. The case V(r) = -S(r) is also considered.
SURFACE GRAVITY AND HAWKING TEMPERATURE FROM ENTROPIC FORCE VIEWPOINT
Authors: EE CHANG-YOUNG , EUNE MYUNGSEOK , KIMM KYOUNGTAE , LEE DAEHO
Published: October 2010

We consider a freely falling holographic screen for the Schwarzschild and Reissner–Nordström black holes and evaluate the entropic force à la Verlinde. When the screen crosses the event horizon, the temperature of the screen agrees to the Hawking temperature and the entropic force gives rise to the surface gravity for both of the black holes.
REAL OR IMAGINARY? ON PAIR CREATION IN DE SITTER SPACE
Authors: AKHMEDOV EMIL T.
Published: October 2010

Using properly defined Feynman propagator we obtain nonzero imaginary contribution to the scalar field effective action in even-dimensional de Sitter space. Such a propagator follows from the path integral in de Sitter space and obeys composition principle proposed in arXiv:0709.2899. The obtained expression for the effective action shows particle production with the Gibbons–Hawking rate.
PARTICLE PRODUCTION AND TRANSPLANCKIAN PROBLEM ON THE NONCOMMUTATIVE PLANE
Authors: RINALDI MASSIMILIANO
Published: October 2010

We consider the coherent state approach to noncommutativity and we derive from it an effective quantum scalar field theory. We show how the noncommutativity can be taken into account by a suitable modification of the Klein–Gordon product, and of the equal-time commutation relations. We prove that, in curved space, the Bogoliubov coefficients are unchanged, hence the number density of the produced particle is the same as for the commutative case. What changes though is the associated energy density, and this offers a simple solution to the transplanckian problem.
GAUGE THEORY OF GRAVITY WITH DE SITTER SYMMETRY AS A SOLUTION TO THE COSMOLOGICAL CONSTANT PROBLEM AND THE DARK ENERGY PUZZLE
Authors: CHEN PISIN
Published: October 2010

We propose a solution to the longstanding cosmological constant (CC) problem which is based on the fusion of two existing concepts. The first is the suggestion that the proper description of classical gravitational effects is the gauge theory of gravity in which the connection instead of the metric acts as the dynamical variable. The resulting field equation does not then contain the CC term. This removes the connection between the CC and the quantum vacuum energy, and therefore addresses the old CC problem of why quantum vacuum energy does not gravitate. The CC-equivalent in this approach arises from the constant of integration when reducing the field equation to the Einstein equation. The second is the assumption that the universe obeys de Sitter symmetry, with the observed accelerating expansion as its manifestation. We combine these ideas and identify the constant of integration with the inverse-square of the radius of curvature of the de Sitter space. The origin of dark energy (DE) is therefore associated with the inherent spacetime geometry, with the smallness of DE protected by symmetry. This addresses the new CC problem, or the DE puzzle. This approach, however, faces major challenges from quantum considerations. These are the ghost problem associated with higher order gravity theories and the quantum instability of the de Sitter spacetime. We discuss their possible remedies.
LEARNING SVM WITH COMPLEX MULTIPLE KERNELS EVOLVED BY GENETIC PROGRAMMING
Authors: DIOŞAN LAURA , ROGOZAN ALEXANDRINA , PECUCHET JEAN-PIERRE
Published: October 2010

Classic kernel-based classifiers use only a single kernel, but the real-world applications have emphasized the need to consider a combination of kernels — also known as a multiple kernel (MK) — in order to boost the classification accuracy by adapting better to the characteristics of the data. Our purpose is to automatically design a complex multiple kernel by evolutionary means. In order to achieve this purpose we propose a hybrid model that combines a Genetic Programming (GP) algorithm and a kernel-based Support Vector Machine (SVM) classifier. In our model, each GP chromosome is a tree that encodes the mathematical expression of a multiple kernel. The evolutionary search process of the optimal MK is guided by the fitness function (or efficiency) of each possible MK. The complex multiple kernels which are evolved in this manner (eCMKs) are compared to several classic simple kernels (SKs), to a convex linear multiple kernel (cLMK) and to an evolutionary linear multiple kernel (eLMK) on several real-world data sets from UCI repository. The numerical experiments show that the SVM involving the evolutionary complex multiple kernels perform better than the classic simple kernels. Moreover, on the considered data sets, the new multiple kernels outperform both the cLMK and eLMK — linear multiple kernels. These results emphasize the fact that the SVM algorithm requires a combination of kernels more complex than a linear one in order to boost its performance.
NUMERICAL NEGATIVE SELECTION ALGORITHM
Authors: CAI TAO , JU SHIGUANG , NIU DEJIAO
Published: October 2010

The artificial immune algorithm is the hot topic in much research such as the intrusion detection system, the information retrieval system and the data mining system. The negative selection algorithm is the typical artificial immune algorithm. A common representation of binary strings for antibody (detector) and antigen have been associated with inefficiencies when generating detector and inspecting antigen. We use a single integer to represent the detector and provide the basis of improving negative selection algorithm efficiency. In the detector generation algorithm, extracting sub-strings in self that its length is larger than threshold and converting them to single integer in numerical interval, then the rest integers in numerical interval are selected as numerical detectors. It can reduce the time and space overhead of detector generation and provide the facility to analyze the positive and negative errors when antigen inspection. The numerical matching rule is given. The B-tree is used to create index of numerical detector. Extracting sub-strings in antigen that its length is larger than threshold and converting them to some integers. If there is the same value as those integers in the index of numerical detector, then the antigen matches one numerical detector. It can improve the efficiency of antigen inspection. Finally the prototype of the numerical negative selection algorithm and negative selection algorithm are realized to test the overhead of the detector generation and antigen inspection using the live data set. The results show that the numerical negative selection algorithm can reduce the time and space overhead and avoid fluctuation of the overhead.
LAGRANGIAN FEYNMAN FORMULAS FOR SECOND-ORDER PARABOLIC EQUATIONS IN BOUNDED AND UNBOUNDED DOMAINS
Authors: BUTKO YANA A. , GROTHAUS MARTIN , SMOLYANOV OLEG G.
Published: October 2010

In this note a class of second-order parabolic equations with variable coefficients, depending on coordinate, is considered in bounded and unbounded domains. Solutions of the Cauchy–Dirichlet and the Cauchy problems are represented in the form of a limit of finite-dimensional integrals of elementary functions (such representations are called Feynman formulas). Finite-dimensional integrals in the Feynman formulas give approximations for functional integrals in the corresponding Feynman–Kac formulas, representing solutions of these problems. Hence, these Feynman formulas give an effective tool to calculate functional integrals with respect to probability measures generated by diffusion processes with a variable diffusion coefficient and absorption on the boundary.
WHITE NOISE LÉVY–MEIXNER PROCESSES THROUGH A TRANSFER PRINCIPAL FROM ONE-MODE TO ONE-MODE TYPE INTERACTING FOCK SPACES
Authors: ACCARDI LUIGI , BARHOUMI ABDESSATAR , RIAHI ANIS
Published: October 2010

Consider the Lévy–Meixner one-mode interacting Fock space {ΓLM, 〈 ⋅, ⋅ 〉LM}. Inspired by a derivative formula appearing in 〈 ⋅, ⋅ 〉LM, we define scalar products 〈 ⋅, ⋅ 〉LM , nin symmetric n-particle spaces. Then, we introduce a class of one-mode type interacting Fock spaces [Formula: see text] naturally associated to the one-dimensional infinitely divisible distributions with Lévy–Meixner type {μr; r > 0}. The Fourier transform in generalized joint eigenvectors of a family [Formula: see text] of Lévy–Meixner Jacobi fields provides a way to explicit a unitary isomorphism 𝔘LMbetween [Formula: see text] and the so-called Lévy–Meixner white noise space [Formula: see text]. We derive a chaotic decomposition property of the quadratic integrable functionals of the Lévy–Meixner white noise processes in terms of an appropriate Wick tensor product. For their stochastic regularity, we give explicit form and sharp estimate of the associated Donsker's delta function.
bm-INDEPENDENCE AND bm-CENTRAL LIMIT THEOREMS ASSOCIATED WITH SYMMETRIC CONES
Authors: WYSOCZAŃSKI JANUSZ
Published: October 2010

We study the properties of the (noncommutative) bm-independence of algebras, indexed by partially ordered sets. The index sets are given by positive cones, in particular the symmetric cones, which include the positive-definite Hermitian matrices with complex or quaternionic entries. We formulate and prove the general versions of the bm-Central Limit Theorems for bm-independent random variables, indexed by lattices in such positive cones. The limit measures we obtain are symmetric and compactly supported on the real line. Their (even) moment sequences (gn)n≥0satisfy the generalized recurrence for the Catalan numbers: [Formula: see text], where the coefficients γ(r) are computed by the Euler's beta-function of the first kind, related to the given positive cone. Example of a nonsymmetric cone, the Vinberg's cone, is also studied in this context.
THE DECOHERENCE-FREE SUBALGEBRA OF A QUANTUM MARKOV SEMIGROUP WITH UNBOUNDED GENERATOR
Authors: DHAHRI AMEUR , FAGNOLA FRANCO , REBOLLEDO ROLANDO
Published: October 2010

Let [Formula: see text] be a quantum Markov semigroup on [Formula: see text] with a faithful normal invariant state ρ. The decoherence-free subalgebra [Formula: see text] of [Formula: see text] is the biggest subalgebra of [Formula: see text] where the completely positive maps [Formula: see text] act as homomorphisms. When [Formula: see text] is the minimal semigroup whose generator is represented in a generalised GKSL form [Formula: see text], with possibly unbounded H, Lℓ, we show that [Formula: see text] coincides with the generalised commutator of [Formula: see text] under some natural regularity conditions.

As a corollary we derive simple sufficient algebraic conditions for convergence towards a steady state based on multiple commutators of H and Lℓ.

We give examples of quantum Markov semigroups [Formula: see text], with h infinite-dimensional, having a non-trivial decoherence-free subalgebra.
An Electrochemical Engineering Perspective of Nitric Oxide in Tumors: Why the Combination of an Allosteric Effector of Hemoglobin with Dietary Sodium Nitrite Should Be Effective in Treating Vascularized Tumors?
Authors: Heller Adam
Published: October 2010

At high (~10-6 M) concentrations nitric oxide (NO), over-expressed in many tumors, induces apoptosis (controlled suicide of cells), which is of essence in avoiding cell proliferation. The excess NO in vascularized tumors is, however, depleted by out-diffusion to blood, where it S-nitrosates proteins and peptides. The out-diffusion explains the observations of Judah Folkman of the dormancy of tumors until their vascularization and their virulence after vascularization. The export of NO from tumors to blood could be slowed by converting part of the nitrite stored in erythrocytes to NO and nitrate in a reaction catalyzed by deoxyhemoglobin. As shown by Max Perutz, oxyhemoglobin is converted to deoxyhemoglobin upon binding an allosteric effector, such as inositol hexaphosphate, bezafibrate or efaproxiral. Local administration the effector, in combination with dietary intake of NaNO2, should raise the tumor-passing blood NO concentration, reduce the tumor to blood NO flux and increase the likelihood of apoptosis.
Combined Chitosan Nano-Bead with Microfluidic-Microelectric Traps of Lead (II) Chelation in Continuous Bloodstream Flow
Authors: Wang Ming-Wen
Published: October 2010

The selective sorting of Pb2+ ions in bloodstream flow has been carried out via mixed chitosan nano-beads aqua-solution and then selectively sponge up the Pb2+ ions by a chelating mechanism. To obtain an efficient chelating reaction and a chelating nanobead that can be attracted and separated from the bloodstream flow, a microfluidic component of a microchannel with electrodes has been designed and fabricated by micro-electromechanical process. A local dielectrophoretic force obtained from nonuniform electric fields was elected to manipulate the chelating nanobeads in a continuous bloodstream flow. The experimental studies indicate that the chelating nanobeads undergoes positive dielectrophoresis when suspended in a continuous flow (Re=5.0) and exposed to RF/AC fields at 13.56 MHz frequency. Through this device, the microchannel with electrodes provides a local dielectrophrosis field which is strong enough to manipulate and separate the chelating nanobeads in a continuous bloodstream flow.
The Biological Compatibility of Porous Surface of Titanium Oxide
Authors: Hsieh Pei-Huan , Chen Min-Hua
Published: October 2010

In this study, porous surface structure of Ti/TiO2 is development for the tooth implant. This kind of structure is made by anode treatment processes with various conditions. The optimized porous surface structure of Ti/TiO2 is treated in the electrolyte within SO42- and PO43- ions. The pH value of electrolyte is the parameter to modify the roughness of the surface. By the conditions of the experiment, the roughness keeps on sub-micro level. Moreover, the biological compatibility test, an important experiment of medical devices, is done to confirm the performance of the implant. The results showed that the treated surface feature is suitable for cells growth, and the cell proliferation performance is better than the raw material, machined Ti surface, about 10%.
Bone-Like Apatite Formed on the Surface of Titanium via a Simulated Body Fluid by the Electro-Chemical Deposit Processing
Authors: Kuo Tzu H. , Chen Min-Hua
Published: October 2010

A simple chemical method was established for inducing bioactivity of Ti and its alloys. In this study, the chemical treatment with alkaline aqueous solution was attempted to Ti implant to form TiO2 on its surface. Thus, treated substrates formed a dense and uniform bonelike apatite layer on their surfaces in the simulated body fluid (SBF) with ion concentrations nearly equal to those of human blood plasma. The forming time of apatite layer on the surface of Ti implant by the electro-chemical deposit process with different current and loading time was decreased.
In Vitro Evaluation of Osteoblast-Like Cell Adhesion and Proliferation on Titanium Oxide Film Formed by Sand-Blasted Titanium Anode Treatment Process
Authors: Lin Yi , Hsieh Pei-Huan
Published: October 2010

The aim of the present study was to evaluate the in vitro cyto-compatibility of titanium oxide layers which were formed by electrochemical anode treatment on sand-blasted titanium plates. The in vitro biological response was characterized by cell morphology, adhesion, proliferation activity. We investigate those responses of MG-63 cells, one kind of human osteoblast-like cell lines, cultivated on these TiO2 films of sandblasted titanium plates formed by different electrochemical anode treatment conditions. The results showed that surface roughness was affected by the sandblasting condition majorly. The higher voltages of anodic treatment were applied, the thicker titanium oxide layers were formed. These thicker titanium oxide layers also reduced the surface roughness slightly. The cell adhesion and proliferation performance of MG63 osteoblast-like cells revealed that the surface which was sandblasted by φ106-125 μm alumina was the better condition for osteoblast-like cell growth.
Synthesis of Birnessite Type MnO2 Nanotubes and Their Application in Aqueous Supercapacitors
Authors: Roberts Alexander J. , Slade Robert C. T.
Published: October 2010

Potassium birnessite nanotubes have been made through a templated hydrothermal route with specific surface areas and pore volumes as high as 110 m2 g-1 and 0.54 cm3 g-1 respectively. After casting into electrode films and assembling into hybrid supercapacitor cells, good cyclability has been demonstrated, with high coulombic efficiencies, with changes in the electrodes during cycling being monitored through electrochemical impedance spectroscopy. High specific capacitances have been observed, with values approaching 350 F g-1 at current densities of 0.1 A g-1. Energy densities approaching 90 W h g-1 have been achieved at low current densities, with power densities over 75000 W kg-1 at high current densities.
Perfluoro Aryl Boronic Esters as Redox Shuttle Additives in Lithium-Ion Batteries
Authors: Patterson Mary L. , Taggougui Mohamed
Published: October 2010

A new family of redox shuttle additives is being developed at Argonne National Laboratories and tested at EnerDel for eventual application in large format batteries that will be used in military, vehicular, and grid storage applications. Perfluoro aryl boronic esters are redox active in the 4.4 to 4.6 V range, making them ideal for use in lithium ion batteries employing high voltage cathodes. Electrochemical testing has been performed on the initial candidate from this family, namely 2-(pentafluorophenyl)-tetrafluoro-1,3,2-benzodioxaborole (BDB), to determine the E0 value of 4.43 V vs. Li/Li+ and the diffusion coefficient of 1.38 x 10-5 cm2/sec in standard electrolyte. Initial battery testing has been performed using a lithium nickel cobalt manganese oxide cathode and a carbonaceous anode. The shuttle molecule has little or no detrimental effect on the cell performance; however, the overcharge protection is not robust and this may be due to contaminants.
Parametric Studies of the Direct Alcohol Phosphoric Acid Fuel Cell
Authors: Fan Simon , Wilkinson David , Wang Haijiang
Published: October 2010

Higher temperature alcohol fuel cells have been shown to have higher activity and increased performance output when compared to lower temperature alcohol fuel cells. In this work, the Direct Alcohol Phosphoric Acid Fuel Cell (DAPAFC) with Pt Black as catalyst and Phosphoric Acid/Silicon Cabride (SiC) as an electrolyte/separator is investigated. Parametric studies are conducted to demonstrate the effects of such parameters as the stream pressures, higher temperature operation (120-180ºC), and the thickness of the SiC separator, etc. Results show that the cell performance is comparable to that of a vapour fed fuel cell with Nafion® membrane at the same operating conditions. However the DAPAFC has the ability to go to a higher temperature range because its conductivity is independent of water content. This type of fuel cell demonstrates stability with performance degradation less than 7 mV/hr and performance improvement in a higher temperature range when compared to the conventional PEMFC.
Two-Phase Flow Pressure Drop Hysteresis under Typical Operating Conditions for a Proton Exchange Membrane Fuel Cell
Authors: Anderson Ryan , Wilkinson David , Bi Xiaotao , Zhang Lifeng
Published: October 2010

Two-phase flow pressure drop hysteresis was studied under conditions typical of an operating PEM fuel cell. Two-phase flow hysteresis occurs when the gas and liquid flow rates are increased and decreased along the same path but exhibit different pressure drops. Variables studied include temperature (30-90oC), air stoichiometry (1-4), and gas diffusion layer. The results were analyzed relative to a baseline of fully humidified air at 75oC and a stoichiometry of 2 with a SGL Carbon 25 BC GDL. The percentage change between ascending and descending pressure drop is used to quantify the relative magnitude of the hysteresis. It was found that a sufficient air stoichiometry ({greater than or equal to}4) can reduce the hysteresis, the GDL properties affect the water breakthrough mechanism and shift the onset of the hysteresis zone, and higher temperatures reduce the relative magnitude of the hysteresis effect. These results correlate well with photographs of the cathode channel two-phase flow.
Electrocatalytic Properties of PdCu Oxygen Reduction for PEM Fuel Cell
Authors: Marti´nez-Casillas Diana C. , Va´zquez-Huerta Gerardo , Solorza-Feria Omar
Published: October 2010

A study of the oxygen reduction reaction on PdCu electrocatalyst synthesized by a NaBH4 reduction of PdCl2 and CuCl in a THF solution was examined in a 0.5 M H2SO4 electrolyte, at 25 °C. The electrochemical techniques used were cyclic voltammetry (CV) and rotating disc electrode (RDE). The electrocatalyst was characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The physical characterization showed that the method of synthesis allows the formation of spherical agglomerated nanocrystalline particles about 11 nm in size. The PdCu catalyst exhibited high current densities for the ORR compared to that obtained on nanometric Pd catalyst synthesized by the same method.
Long-Term Stability of Nafion Hybrid Membranes for Use in Vanadium Redox-Flow Batteries
Authors: Drillkens Julia , Schulte Dominik , Sauer Dirk Uwe
Published: October 2010

The membrane is the key component of a redox-flow system. It should possess high proton conductivity and should avoid cross contamination due to the diffusion of ions of the active material through membrane pores. A membrane with drastically reduced cross contamination ability would overcome the main problem of several redox couples and in consequence it would allow redoxflow systems with higher energy density and lower material costs. In previous works cross contamination of Nafion membranes could have been reduces significantly by several modification methods with SiO2 nano particles. This work deals with the long-term stability of this improvement that was investigated by cycling modified membranes for several weeks and analyzing the electrical performance in dependency of time. Nafion membrane modified with TEOS/DEDMS/NH3 showed a very good long-term stability.
Electrodeposition of CoMn onto Stainless Steels Interconnects for Increased Lifetimes in SOFCs
Authors: Hall Timothy , McCrabb Heather , Wu Junwei , Zhang Hui , Liu Xingbo , Taylor E. J.
Published: October 2010

A pulse and pulse reverse electrochemical deposition process is being developed for cost effective coating of solid oxide fuel cell (SOFC) interconnects. Faraday Technology and WVU demonstrated that the developed process could produce uniform dense, crack-free, well-adhered CoMn alloy coatings of various compositions on a 5cm x 5cm 441 stainless steel interconnect surface. The post-deposition thermal treatment converted the CoMn alloy coatings to (Mn,Co)3O4 spinels in which a coating thickness of ~3µm was shown to be sufficient to mitigate chromia diffusion and oxidation. Various electrochemical deposition processing parameters are examined to determine their affect on the coatings performance, while the coatings thickness and composition are also varied in order to obtain preliminary coating performance limits.
Fabrication and Properties of SnO2-Based Inert Gas Anodes for Electrowinning
Authors: Mokkelbost Tommy , Paulsen Ove , Xiao Saijun , Haarberg Geir M. , Ratvik Arne P.
Published: October 2010

Porous inert SnO2-based anodes rammed inside a mullite tube, for an initial study of their depolarization effect applying reducing gas, have been prepared. The anodes were prepared by using commercial SnO2 materials which were crushed down and mixed with a SnO2-CuO-Sb2O3 binder phase and sintered at 1200-1300 ° C in air. The anodes were characterized for electrical and mechanical properties and used as depolarizing inert anodes applying H2 as reducing gas in electrowinning of Ag in NaCl-CaCl2 melts at 680 ° C. The mechanical and electrical properties were found suitable for applications as inert anodes. The depolarizing effect was confirmed by a reduction of cell voltage and electrode potentials while introducing H2 through the inert anodes. However, reactions between the melt and anode resulted in a Ca-SnO2 phase reducing the electrical conductivity of the anodes and increasing the anode potential during electrolysis compared to the initial potential.
Development of a Lithium Air Rechargeable Battery
Authors: Stevens Philippe , Toussaint Gwenaëlle , Caillon Georges , Viaud Patrick , Vinatier Philippe , Cantau Christophe , Fichet Odile , Sarrazin Christian , Mallouki Mohamed
Published: October 2010

Rechargeable aqueous lithium-air cells have been developed and manufactured with the objective of analysing the limitations of the technology. The barriers to the technology have been identified and solutions to some of them have been successfully demonstrated in this study.
Development of a Novel Zinc/Air Fuel Cell with a Zn Foam Anode, a PVA/KOH Membrane and a MnO2/SiOC-Based Air Cathode
Authors: Drillet Jean-Francois , Adam Michael , Barg Suelen , Herter Alexander , Koch Dietmar , Schmidt Volkmar , Wilhelm Michaela
Published: October 2010

A new type of zinc/air fuel cell comprising a Hg/Pb free Zn foam anode, a PVA/KOH electrolyte membrane and a MnO2/SiOC-based cathode was developed in this work. The electrochemical activity of the zinc foam and air electrode was investigated in 6 M KOH under half-cell conditions. The pristine ZnO layer of the foam matrix favoured direct oxidation of the zinc particles to zinc oxide in 6 M KOH. In the laboratory cell, a specific energy of about 500 mWh g-1zinc was measured at 5 mA discharging current with a zinc foam, a PVA/KOH/H2O membrane and a MnO2+Vulcan/carbon paper cathode. A correlation between cell performances and porosity of the zinc foam was found. However, stability of the Zn foam and SiOC GDL materials towards KOH should be improved.
Development of a Rechargeable Zinc-Air Battery
Authors: Toussaint Gwenaëlle , Stevens Philippe , Akrour Laurent , Rouget Robert , Fourgeot Fabrice
Published: October 2010

An electrically rechargeable zinc-air cell was developed and demonstrated using a bi-electrode on the cathode side and a 3D zinc electrode. About 200 cycles corresponding to 5000h of operation was achieved with this configuration. An innovating hybrid bi-electrode was evaluated which significantly increase the energy efficiency of our system to about 70% with an energy density close to 110 wh/kg and also improves the power response of the zinc air battery for punctual power demand application.
Random mutagenesis of the mouse genome: a strategy for discovering gene function and the molecular basis of disease
Authors: Nguyen Nhung , Judd Louise M. , Kalantzis Anastasia , Whittle Belinda , Giraud Andrew S. , van Driel Ian R.
Published: October 2010

Mutagenesis of mice with N-ethyl- N-nitrosourea (ENU) is a phenotype-driven approach to unravel gene function and discover new biological pathways. Phenotype-driven approaches have the advantage of making no assumptions about the function of genes and their products and have been successfully applied to the discovery of novel gene-phenotype relationships in many physiological systems. ENU mutagenesis of mice is used in many large-scale and more focused projects to generate and identify novel mouse models for the study of gene functions and human disease. This review examines the strategies and tools used in ENU mutagenesis screens to efficiently generate and identify functional mutations.
Differential immune and genetic responses in rat models of Crohn's colitis and ulcerative colitis
Authors: Shi Xuan-Zheng , Winston John H. , Sarna Sushil K.
Published: October 2010

Crohn's disease and ulcerative colitis are clinically, immunologically, and morphologically distinct forms of inflammatory bowel disease (IBD). However, smooth muscle function is impaired similarly in both diseases, resulting in diarrhea. We tested the hypothesis that differential cellular, genetic, and immunological mechanisms mediate smooth muscle dysfunction in two animal models believed to represent the two diseases. We used the rat models of trinitrobenzene sulfonic acid (TNBS)- and dextran sodium sulfate (DSS)-induced colonic inflammations, which closely mimic the clinical and morphological features of Crohn's disease and ulcerative colitis, respectively. DSS inflammation induced oxidative stress initially in mucosa/submucosa, which then propagated to the muscularis externa to impair smooth muscle function. The muscularis externa showed no increase of cytokines/chemokines. On the other hand, TNBS inflammation almost simultaneously induced oxidative stress, recruited or activated immune cells, and generated cytokines/chemokines in both mucosa/submucosa and muscularis externa. The generation of cytokines/chemokines did not correlate with the recruitment and activation of immune cells. Consequently, the impairment of smooth muscle function in DSS inflammation was primarily due to oxidative stress, whereas that in TNBS inflammation was due to both oxidative stress and proinflammatory cytokines. The impairment of smooth muscle function in DSS inflammation was due to suppression of Gαq protein of the excitation-contraction coupling. In TNBS inflammation, it was due to suppression of the α1C1b subunit of Cav1.2b channels, CPI-17 and Gαq. TNBS inflammation increased IGF-1 and TGF-β time dependently in the muscularis externa. IGF-1 induced smooth muscle hyperplasia; both IGF-1 and TGF-β induced hypertrophy. In conclusion, both TNBS and DSS induce transmural inflammation, albeit with different types of inflammatory mediators. The recruitment or activation of immune cells does not correlate directly with the intensity of generation of inflammatory mediators. The inflammatory mediators in TNBS and DSS inflammations target different genes to impair smooth muscle function.
Differential organization of excitatory and inhibitory synapses within the rat dorsal vagal complex
Authors: Babic Tanja , Browning Kirsteen N. , Travagli R. Alberto
Published: October 2010

The dorsal motor nucleus of the vagus (DMV) is pivotal in the regulation of upper gastrointestinal functions, including motility and both gastric and pancreatic secretion. DMV neurons receive robust GABA- and glutamatergic inputs. Microinjection of the GABAA antagonist bicuculline (BIC) into the DMV increases pancreatic secretion and gastric motility, whereas the glutamatergic antagonist kynurenic acid (KYN) is ineffective unless preceded by microinjection of BIC. We used whole cell patch-clamp recordings with the aim of unveiling the brain stem neurocircuitry that uses tonic GABA- and glutamatergic synapses to control the activity of DMV neurons in a brain stem slice preparation. Perfusion with BIC altered the firing frequency of 71% of DMV neurons, increasing firing frequency in 80% of the responsive neurons and decreasing firing frequency in 20%. Addition of KYN to the perfusate either decreased (52%) or increased (25%) the firing frequency of BIC-sensitive neurons. When KYN was applied first, the firing rate was decreased in 43% and increased in 21% of the neurons; further perfusion with BIC had no additional effect in the majority of neurons. Our results indicate that there are several permutations in the arrangements of GABA- and glutamatergic inputs controlling the activity of DMV neurons. Our data support the concept of brain stem neuronal circuitry that may be wired in a finely tuned organ- or function-specific manner that permits precise and discrete modulation of the vagal motor output to the gastrointestinal tract.
A novel approach to in vivo mitral valve stress analysis
Authors: Xu Chun , Brinster Clay J. , Jassar Arminder S. , Vergnat Mathieu , Eperjesi Thomas J. , Gorman Robert C. , Gorman Joseph H. , Jackson Benjamin M.
Published: October 2010

Three-dimensional (3-D) echocardiography allows the generation of anatomically correct and time-resolved geometric mitral valve (MV) models. However, as imaged in vivo, the MV assumes its systolic geometric configuration only when loaded. Customarily, finite element analysis (FEA) is used to predict material stress and strain fields rendered by applying a load on an initially unloaded model. Therefore, this study endeavors to provide a framework for the application of in vivo MV geometry and FEA to MV physiology, pathophysiology, and surgical repair. We hypothesize that in vivo MV geometry can be reasonably used as a surrogate for the unloaded valve in computational (FEA) simulations, yielding reasonable and meaningful stress and strain magnitudes and distributions. Three experiments were undertaken to demonstrate that the MV leaflets are relatively nondeformed during systolic loading: 1) leaflet strain in vivo was measured using sonomicrometry in an ovine model, 2) hybrid models of normal human MVs as constructed using transesophageal real-time 3-D echocardiography (rt-3DE) were repeatedly loaded using FEA, and 3) serial rt-3DE images of normal human MVs were used to construct models at end diastole and end isovolumic contraction to detect any deformation during isovolumic contraction. The average linear strain associated with isovolumic contraction was 0.02 ± 0.01, measured in vivo with sonomicrometry. Repeated loading of the hybrid normal human MV demonstrated little change in stress or geometry: peak von Mises stress changed by <4% at all locations on the anterior and posterior leaflets. Finally, the in vivo human MV deformed minimally during isovolumic contraction, as measured by the mean absolute difference calculated over the surfaces of both leaflets between serial MV models: 0.53 ± 0.19 mm. FEA modeling of MV models derived from in vivo high-resolution truly 3-D imaging is reasonable and useful for stress prediction in MV pathologies and repairs.