bluuebunny/crossref_metadata_2025 huggingface dataset:
Fibrolase: Trials and Tribulations
Authors: Markland Francis S. , Swenson Steve
Published: April 2010

Fibrolase is the fibrinolytic enzyme isolated from Agkistrodon contortrix contortrix (southern copperhead snake) venom. The enzyme was purified by a three-step HPLC procedure and was shown to be homogeneous by standard criteria including reverse phase HPLC, molecular sieve chromatography and SDS-PAGE. The purified enzyme is a zinc metalloproteinase containing one mole of zinc. It is composed of 203 amino acids with a blocked amino-terminus due to cyclization of the terminal Gln residue. Fibrolase shares a significant degree of homology with enzymes of the reprolysin sub-family of metalloproteinases including an active site homology of close to 100%; it is rapidly inhibited by chelating agents such as EDTA, and by alpha2-macroglobulin (α2M). The enzyme is a direct-acting thrombolytic agent and does not rely on plasminogen for clot dissolution. Fibrolase rapidly cleaves the A(α)-chain of fibrinogen and the B(β)-chain at a slower rate; it has no activity on the γ-chain. The enzyme exhibits the same specificity with fibrin, cleaving the α-chain more rapidly than the β-chain. Fibrolase was shown to have very effective thrombolytic activity in a reoccluding carotid arterial thrombosis model in the canine. A recombinant version of the enzyme was made in yeast by Amgen, Inc. (Thousand Oaks, CA, USA) and called alfimeprase. Alfimeprase is identical to fibrolase except for a two amino acid truncation at the amino-terminus and the insertion of a new amino-terminal amino acid in the truncated protein; these changes lead to a more stable enzyme for prolonged storage. Alfimeprase was taken into clinical trials by Nuvelo, Inc. (San Carlos, CA), which licensed the enzyme from Amgen. Alfimeprase was successful in Phase I and II clinical trials for peripheral arterial occlusion (PAO) and central venous access device (CVAD) occlusion. However, in Phase III trials alfimeprase did not meet the expected end points in either PAO or CVAD occlusion and in a Phaase II stroke trial, and Nuvelo dropped further development in 2008.
Training Health Professionals in Bioinformatics
Authors: López-Campos G. , López-Alonso V. , Martin-Sanchez F.
Published: April 2010

Background: Genomic technologies and particularly bioinformatics have significantly changed biomedical research along the last decade and are being recognized as potential methods for application also in medical practice and public health. There exists a growing need for different collectives of the healthcare sector to receive training in the methods, tools and databases related with these new areas.

Objectives: This paper describes the teaching experience of our department during the last ten years and analyzes past activities designed for teaching bioinformatics to different groups of health professionals. We aim to illustrate the main lessons learned and offer useful clues to other groups interested in setting up training initiatives in bioinformatics for health professionals.

Methods: The group selected several methodologies for the training activities (“face-to-face”, online/e-learning) on the basis of three criteria: 1) the target collective, 2) the contents of the course, and 3) its length. Courses were evaluated and the results are hereby presented and discussed.

Results: National and international training courses on bioinformatics, biomedical informatics and genomics were developed according to specific requirements defined by the profile of each of the targeted health professional group. These activities provided the students with the necessary skills for better understanding the use of bioinformatics tools and databases and the appropriate way of applying them into specific health domains.

Conclusions: The increasing demand of training courses in new technologies related to genomics and bioinformatics by health professionals provides a good opportunity for the development of tailored courses based on their specific needs, expectations and demands geared to bridge the gap between research and practice and facilitating their everyday work.
A Medical Informatics Distance-learning Course for Latin America
Authors: Hersh W. , Luna D. , González Bernaldo de Quirós F. , Otero P.
Published: April 2010

Background: There is a growing need and interest worldwide for healthcare and information technology professionals trained in medical informatics. Distance learning technologies are increasingly used to deliver such education, but have mainly been limited to the English language.

Objective: Describe the implementation and student satisfaction of a medical informatics course delivered in Spanish for a Latin American audience.

Methods: The course was based on the 10 x 10 program of the American Medical Informatics Association and Oregon Health & Science University that was translated and adapted to the Latin American setting. The initial course consisted of ten one-week units, currently the course has 15 modules that are delivered in 16 weeks with topics that address the needs of medical informatics in the region. We also administered an anonymous questionnaire of student satisfaction.

Results: A total of 499 individuals have enrolled in the course, and 70% have completed it. Most of the students have been healthcare professionals (86%), with the largest proportion from Argentina. Student satisfaction with all aspects of the course was high. After the initial experience and feedback from the students, the course has been adapted to better meet regional needs.

Conclusion: The initial experience obtained in training healthcare professionals in medical informatics in Latin America in their own language demonstrated that it could be used across the region, and this could represent a model for disseminating knowledge of medical informatics across other languages and cultures.
Testing Conformance and Interoperability of eHealth Applications
Authors: Namli T. , Dogac A.
Published: April 2010

Objective: To explain the common conformance and interoperability testing requirements of eHealth applications through two case studies; one using a prominent eHealth messaging standard, namely HL7 v3 [1], and the other using Integrating the Healthcare Enterprise (IHE) [2] Profiles and to describe how these testing requirements can be addressed through an automated, modular and scenario-based testing framework, namely Test BATN.

Methods: Summarizing the conformance testing requirements of HL7 v3 messages. Illustrating the interoperability testing requirements of IHE Profiles through a scenario based on the IHE XDS, IHE XDS-MS and IHE PIX profiles. Explaining how these requirements can be handled through a dynamic and configurable test framework addressing all the layers in the interoperability stack within a single test scenario.

Results: Conformance and interoperability testing are necessary to maintain correct information exchange as the correctness of the exchanged data is essential in the healthcare domain. There are many standards used in eHealth that the applications need to conform. Additionally, there are profiling initiatives such as IHE and Continua Health Alliance which publish integration profiles addressing a specific clinical need or a use case and describe how to combine or use the existing standards to provide interoperability. However, as the results of our case studies demonstrate, there are many commonalities in the conformance and interoperability testing requirements of these standards and profiles and therefore an integrated testing environment is needed.

Conclusion: Our main conclusion is that rather than having individual testing tools for each standard or initiative, a generic and modular test framework exploiting the commonalities in the testing processes and fostering reusability of modular, pluggable testing components will improve the efficiency of testing. Through the TestBATN framework, we describe how this modularity can be achieved by providing common interfaces facilitating the development of adaptors which allows different testing components to be plugged into the system.
Lower selfing rate at higher altitudes in the alpine plant Eritrichium nanum (Boraginaceae)
Authors: Wirth Lea Rahel , Graf René , Gugerli Felix , Landergott Urs , Holderegger Rolf
Published: April 2010

A general hypothesis on mating patterns in alpine plants states that self‐fertilization should increase with increasing altitude as a result of pollinator limitation at higher altitudes. However, realized selfing rates under natural conditions, as based on genetic progeny analysis, have not yet been determined for any alpine species across altitude. We therefore assessed the realized selfing rates in about 100 open‐pollinated families of the high‐alpine cushion plant Eritrichium nanum, sampled along an altitudinal gradient in the Swiss Alps, by using progeny analysis based on six microsatellites. In marked contrast to the general hypothesis, realized selfing rates in E. nanum significantly decreased with increasing altitude, and only progenies from low altitudes were predominantly selfed. However, the higher selfing rates of individuals at lower altitudes could have been caused by unfavorable weather conditions during early growing season when low‐elevation plants flowered. In summary, our results on selfing rates in an alpine plant across altitude as well as the results of other studies using experimental hand‐pollinations and/or population genetic methods generally do not support the expectation of higher selfing rates at higher altitudes. We therefore ask for further critical examination of realized mating systems in alpine plants.
Characterization of nuclear microsatellite loci in the Neotropical tree Parkia panurensis (Fabaceae)
Authors: Luettmann Kathrin , Michalczyk Inga M. , Mengel Christina , Ziegenhagen Birgit , Heymann Eckhard W. , Pinedo Saboya Pedro P. , Bialozyt Ronald
Published: April 2010

• Premise of the study: We present here a set of nine polymorphic nuclear microsatellite loci, identified for the first time within the neotropical legume tree species Parkia panurensis Benth. ex H. C. Hopkins, which is widespread in western and central Amazonia.

• Methods and Results: To characterize these loci, 33 Parkia panurensis adult trees were analyzed. The number of alleles ranged from eight to 32, with an average of 14.4 alleles per locus. Mean expected heterozygosity ranged from 0.74 to 0.955.

• Conclusions: All nine loci could also be verified in six other Parkia species and polymorphic fragments amplified. The new marker set can be used for future studies of genetic diversity and differentiation, as well as estimation of gene flow and parentage analyses in various Parkia species.
Synthesis of gem-difluoromethylenated analogues of boronolide
Authors: Lin Jing , Qiu Xiao-Long , Qing Feng-Ling
Published: April 2010

The straightforward synthesis of four gem-difluoromethylenated analogues 4–7 of boronolide is described. The key steps of the synthesis include the concise preparation of the key intermediates 12a–b through the indium-mediated gem-difluoropropargylation of aldehyde 9 with the fluorine-containing building block 11 and the efficient construction of α,β-unsaturated-δ-lactones 15a–b via BAIB/TEMPO-procedure.
Preparation, structures and preliminary host–guest studies of fluorinated syn-bis-quinoxaline molecular tweezers
Authors: Etzkorn Markus , Timmerman Jacob C , Brooker Matthew D , Yu Xin , Gerken Michael
Published: April 2010

A series of polycyclic frameworks with fluorinated syn-facial quinoxaline sidewalls has been prepared as potential molecular tweezers for electron-rich guest compounds. Our synthetic route to the cyclooctadiene-derived scaffolds 16a–d takes advantage of the facile isolation of a novel spirocyclic precursor 9b with the crucial syn-orientation of its two alkene moieties. The crystal structure of 16c displays two features typical of a molecular tweezer: inclusion of a solvent molecule in the molecular cleft and self-association of the self-complementary scaffolds. Furthermore, host–guest NMR studies of compound 16c in solution show chemical exchange between the unbound and bound electron-rich guest, N,N,N′,N′-tetramethyl-p-phenylenediamine.
Chemical aminoacylation of tRNAs with fluorinated amino acids for in vitro protein mutagenesis
Authors: Ye Shijie , Ann Berger Allison , Petzold Dominique , Reimann Oliver , Matt Benjamin , Koksch Beate
Published: April 2010

This article describes the chemical aminoacylation of the yeast phenylalanine suppressor tRNA with a series of amino acids bearing fluorinated side chains via the hybrid dinucleotide pdCpA and ligation to the corresponding truncated tRNA species. Aminoacyl-tRNAs can be used to synthesize biologically relevant proteins which contain fluorinated amino acids at specific sites by means of a cell-free translation system. Such engineered proteins are expected to contribute to our understanding of discrete fluorines’ interaction with canonical amino acids in a native protein environment and to enable the design of fluorinated proteins with arbitrary desired properties.
Predicción basada en redes neuronales del tiempo de procesamiento de los trenes desbastador y laminador en una instalación de laminación en caliente
Authors: Colla V. , Vannucci M. , Valentini R.
Published: April 2010

En este artículo se presenta un modelo basado en redes neuronales capaz de predecir el tiempo necesario para pasar las diferentes galgas de un tren desbastador y acabador en función de ciertas características del desbaste y parámetros de proceso. El objetivo final es aumentar la eficacia de la laminación evitando colisiones y colas que provoquen pérdidas de tiempo y energía. Se propone utilizar para esta tarea redes neuronales por su capacidad de predicción en aquellos casos en los que existen relaciones no lineales desconocidas entre las variables de entrada y las de salida. Además, son capaces de aprender de datos industriales reales y, por tanto, no requieren suposiciones previas o modelos matemáticos del proceso, estando la transferibilidad asegurada ya que es posible utilizar distintas bases de datos procedentes de diferentes trenes de laminación.
Algunos aspectos cinéticos de las reacciones de sólidos con cloro
Authors: Kanari N. , Mishra D. , Mochón J. , Verdeja L. F. , Diot F. , Allain E.
Published: April 2010

Este trabajo describe detalladas investigaciones cinéticas en algunas reacciones seleccionadas de cloro-sólido a través de medidas termogravimétricas. Los sólidos estudiados en este artículo incluyen óxidos químicos puros y sulfuros, así como sus materiales naturales de soporte. Los agentes de cloración empleados son mezclas de gases de Cl2+N2 (cloración), Cl2+O2 (oxicloración) y Cl2+O2 (carbocloración). Los resultados se presentan como efecto de varios parámetros en el porcentaje de reacción de estos sólidos con los agentes de cloración. Se ha observado que la reactividad de estos sólidos a través de diferentes agentes de cloración varía ampliamente. Los sulfuros se pudieron clorar a temperatura ambiente mientras que la carbocloración del óxido de cromo (III) sólo fue posible por encima de los 500 °C. La variación del porcentaje de cloración de estos materiales complejos con respecto a la velocidad del gas, composición y temperatura permitió arrojar alguna luz en los posibles mecanismos de reacción y estequiometrías. Los resultados obtenidos se han usado para la eliminación selectiva del hierro de concentrados de cromo, extracción de metales valiosos de materiales sulfhídricos, purificación de muestras de MgO, etc.
Efecto de la recirculación de polvo de fundición de cobre de Chile con altos contenidos de impurezas en la distribución de impurezas durante el proceso de fusión
Authors: Montenegro V. , Sano H. , Fujisawa T.
Published: April 2010

Usualmente, el polvo generado durante el proceso de fusión de concentrado de cobre por el Convertidor Teniente y el Horno Flash en Chile, contienen altos contenidos de cobre, zinc, arsénico y antimonio, entre otros metales. En general, el polvo se recircula al proceso de fusión o se envía a procesos hidrometalúrgicos para recuperación y estabilización. Sin embargo, en los años recientes, la generación de polvo ha aumentado debido a la baja en la calidad del concentrado. Adicionalmente, las normas ambientales se han vuelto más estrictas. Por lo tanto, es deseable entender el comportamiento de estos elementos cuando el proceso opera con recirculación de polvos. En este estudio, el efecto de la recirculación de polvo al proceso de fusión de cobre en la distribución entre la mata, escoria y gas fue evaluado como una función del grado de la mata, cantidad de polvo recirculado, enriquecimiento de oxígeno y temperatura. Se encontró que la concentración en el eje, de metales tales como, arsénico, antimonio y bismuto aumentaron levemente con el polvo recirculado. Por otro lado, la concentración de plomo y zinc depende fuertemente de la recirculación directa de polvo al proceso. Adicionalmente, se encontró que altos niveles de arsénico y antimonio en el polvo, pueden provocar formación y precipitación de arseniatos de cobre y otros metales (speiss), los cuales pueden provocar problemas operacionales de importancia.
Efecto del contenido de aluminio sobre la temperatura de transformación austenita-ferrita en aceros de bajo carbono (Al-Si) eléctricos de grano no-orientado laminados en caliente
Authors: Equihua F. , Salinas A. , Nava E.
Published: April 2010

El objetivo del presente trabajo es investigar el efecto del contenido de aluminio y silicio sobre la temperatura critica de transformación, durante el enfriamiento, en aceros eléctricos de grano no-orientado (GNO) de bajo carbono laminados en caliente. Dos muestras, con diferentes contenidos de aluminio: A=0,22 y B=0,61 % en peso, fueron analizadas mediante la técnica in-situ de difracción de rayos X a alta temperatura. Las muestras fueron austenizadas a 1.050 °C durante 5 min y, subsecuentemente, enfriadas de manera escalonada cada –10 °C dentro de la cámara de alta temperatura instalada en un difractometro Philips X’pert. Los patrones de difracción fueron registrados cada –10 °C durante el enfriamiento desde 1.000 hasta 720 °C. La temperatura de transformación austenita – ferrita, Ar3, fue estimada a partir de los cambios en la intensidad de los picos (110)-α y (111)-γ en función de la temperatura. Los resultados de dichos experimentos mostraron que la temperatura de transformación, Ar3, aumenta con el incremento del contenido de aluminio, desde 0,22 a 0,61 % en peso. Adicionalmente, el rango bifásico (austenita + ferrita) en el sistema Fe-C disminuye con el incremento de aluminio y silicio en los aceros experimentales. Los resultados de difracción de rayos X fueron sustentados por observaciones microestructurales en muestras del acero B, el cual fue sometido tratamientos térmicos similares a los empleados en los experimentos de DR-X. Se observaron finas capas de ferrita a temperaturas cercanas a la temperatura Ar3 obtenida experimentalmente en el acero B.
SMAD4 Is Required for Development of Maximal Endotoxin Tolerance
Authors: Pan Hongjie , Ding Enyu , Hu Mai , Lagoo Anand S. , Datto Michael B. , Lagoo-Deenadayalan Sandhya A.
Published: April 2010

Initial exposure of monocytes/macrophages to LPS induces hyporesponsiveness to a second challenge with LPS, a phenomenon termed LPS tolerance. Molecular mechanisms responsible for endotoxin tolerance are not well defined. We and others have shown that IL-1R–associated kinase (IRAK)-M and SHIP-1 proteins, negative regulators of TLR4 signaling, increase in tolerized cells. TGF-β1, an anti-inflammatory cytokine, is upregulated following LPS stimulation, mediating its effect through SMAD family proteins. Using a monocytic cell line, THP1, we show that LPS activates endogenous SMAD4, inducing its migration into the nucleus and increasing its expression. Secondary challenge with high dose LPS following initial low-dose LPS exposure does not increase IRAK-M or SHIP1 protein expression in small hairpin (sh)SMAD4 THP-1 cells compared with control shLUC THP1 cells. TNF-α concentrations in culture supernatants after second LPS challenge are higher in shSMAD4 THP-1 cells than shLUC THP1 cells, indicating failure to induce maximal tolerance in absence of SMAD4 signaling. Identical results are seen in primary murine macrophages and mouse embryonic fibroblasts, demonstrating the biological significance of our findings. TGF-β1 treatment does not increase IRAK-M or SHIP1 protein expression in shSMAD4 THP-1 cells, whereas it does so in shLUC THP1 cells, indicating that TGF-β1 regulates IRAK-M and SHIP1 expression through a SMAD4-dependent pathway. Knockdown of endogenous SHIP1 by shSHIP1 RNA decreases native and inducible IRAK-M protein expression and prevents development of endotoxin tolerance in THP1 cells. We conclude that in THP-1 cells and primary murine cells, SMAD4 signaling is required for maximal induction of endotoxin tolerance via modulation of SHIP1 and IRAK-M.
Link concordance, homology cobordism, and Hirzebruch-type defects from iterated $p$-covers
Authors: Cha Jae Choon
Published: April 2010

We obtain new invariants of topological link concordance and homology cobordism of 3-manifolds from Hirzebruch-type intersection form defects of towers of iterated
p
-covers. Our invariants can extract geometric information from an arbitrary depth of the derived series of the fundamental group, and can detect torsion which is invisible via signature invariants. Applications illustrating these features include the following: (1) There are infinitely many homology equivalent rational 3-spheres which are indistinguishable via multisignatures,
η
-invariants, and
L2
-signatures but have distinct homology cobordism types. (2) There is an infinite family of 2-torsion (amphichiral) knots with non-slice iterated Bing doubles; as a special case, we give the first proof of the conjecture that the Bing double of the figure eight knot is not slice. (3) There exist infinitely many torsion elements at any depth of the Cochran–Orr–Teichner filtration of link concordance.
Maximum principles and the method of moving planes for a class of degenerate elliptic linear operators
Authors: Monticelli Dario D.
Published: April 2010

In this paper we deal with maximum principles for a class of linear, degenerate elliptic differential operators of the second order. In particular the Weak and Strong Maximum Principles are shown to hold for this class of operators in bounded domains, as well as a Hopf type lemma, under suitable hypothesis on the degeneracy set of the operator. We derive, as consequences of these principles, some generalized maximum principles and an a priori estimate on the solutions of the Dirichlet problem for the linear equation. A good example of such an operator is the Grushin operator on

ℝ^{d+k}

, to which we devote particular attention. As an application of these tools in the degenerate elliptic setting, we prove a partial symmetry result for classical solutions of semilinear problems on bounded, symmetric and suitably convex domains, which is a generalization of the result of Gidas–Ni–Nirenberg [12, 13] and a nonexistence result for classical solutions of semilinear equations with subcritical growth defined on the whole space, which is a generalization of the result of Gidas–Spruck [14] and Chen–Li [6]. The method we use to obtain these results is the method of moving planes, implemented just in the directions parallel to the degeneracy set of the Grushin operator.
Cohomology of coherent sheaves and series of supernatural bundles
Authors: Eisenbud David , Schreyer Frank-Olaf
Published: April 2010

We show that the cohomology table of any coherent sheaf on projective space is a convergent—but possibly infinite—sum of positive real multiples of the cohomology tables of what we call
supernatural
sheaves.
The Kodaira dimension of the moduli space of Prym varieties
Authors: Farkas Gavril , Ludwig Katharina
Published: April 2010

We study the enumerative geometry of the moduli space

\mathcal R_g

of Prym varieties of dimension

g–1

. Our main result is that the compactication of

\mathcal R_g

is of general type as soon as

g > 13

and

g

is different from

15

. We achieve this by computing the class of two types of cycles on

\mathcal R_g

: one defined in terms of Koszul cohomology of Prym curves, the other defined in terms of Raynaud theta divisors associated to certain vector bundles on curves. We formulate a Prym–Green conjecture on syzygies of Prym-canonical curves. We also perform a detailed study of the singularities of the Prym moduli space, and show that for

g ≥4

, pluricanonical forms extend to any desingularization of the moduli space.
NMR‐Based Screening and Drug Discovery
Authors: Craik David J. , Smith Phillippa A. , Clark Richard J.
Published: April 2010

NMR spectroscopy is a powerful technique for determining the structures of molecules in solution. It involves placing a sample in a strong homogeneous magnetic field and irradiating it with radiowaves of defined frequency. The emitted signals provide information about the local molecular environments of nuclei in the sample, from which structures can be derived. NMR can also be used for determining interactions between molecules and is particularly useful for determining the nature of binding interactions between ligands and macromolecules. This information is very important in drug design: by understanding how bioactive molecules interact with a target protein or nucleic acid it is, in principle, possible to design ligands with improved affinity and specificity that may make useful drug leads. In addition to this structure‐based approach to drug design NMR is also useful as a screening tool in drug discovery programs to identify ligands that bind to target macromolecules.
The
FDA
and Drug Regulatory Issues
Authors: Randad Ramnarayan S.
Published: April 2010

The U.S. Food and Drug Administration (FDA) is a part of the U.S. Department of Health and Human Services (HHS). It is responsible for protecting the public health by assuring the safety, efficacy, and security of human and veterinary drugs, biological products, medical devices, our nation's food supply, cosmetics, and products that emit radiation. The FDA is also responsible for advancing the public health by helping to speed innovations that make medicines and foods more effective, safer, and more affordable; and helping the public get the accurate, science‐based information they need to use medicines and foods to improve their health (
http://www.fda.gov/opacom/morechoices/mission.html
).
GPCRHomology Model Development and Application
Authors: Garland Stephen L. , Blaney Frank E.
Published: April 2010

G‐protein‐coupled receptors (GPCRs) are a very important class of proteins for drug discovery. Exciting progress has been made recently in the determination of X‐ray crystal structures. However, despite this, structural coverage of the receptor family is still thin. We lack direct structural knowledge of many important subfamilies, we have only modest detail of the conformational changes associated with receptor activation and we lack robust crystallographic systems for the rapid determination of ligand binding modes. As a consequence, the ability to build and apply homology models for drug discovery at these targets is very valuable. The accuracy of the models has improved in parallel with the increase in available structural data and the models have been successfully applied to a wide range of lead generation and optimization problems.
Ethical Elders: Campus Role Models for Moral Development
Authors: Liddell Debora L. , Cooper Diane L. , Healy Margaret A. , Stewart Dafina Lazarus
Published: April 2010

Dana is a graduate assistant in the second year of a master's program in student personnel. In a class discussion of assistantship issues, Dana reveals that he has decided not to enforce the university's policy of “writing up” all underage students who are in a residence hall room where alcohol is present. He says that in his opinion the punitive nature of the policy, which imposes a $200 fine, flies in the face of any opportunity for learning and drives the targeted behavior further underground. Dana says that the residence hall supervisors know about the decision and that they have discussed the possible ramifications and consequences. As an educator, what is your responsibility to both Dana and to others in the campus community? What are the obligations of others?

The purpose of this article is to explore the layered dimensions of learning in the context of everyday ethical dilemmas and to examine the ways in which student affairs educators, classroom faculty, and institutional leaders can serve as ethical elders on campus. We believe that educators are obligated to serve as ethical role models, especially for students and younger colleagues who aspire to serve as educators themselves.
Electronic and Magnetic Properties of SrTiO3/LaAlO3 Interfaces from First Principles
Authors: Chen Hanghui , Kolpak Alexie M. , Ismail‐Beigi Sohrab
Published: April 2010

A number of intriguing properties emerge upon the formation of the epitaxial interface between the insulating oxides LaAlO3 and SrTiO3. These properties, which include a quasi two‐dimensional conducting electron gas, low temperature superconductivity, and magnetism, are not present in the bulk materials, generating a great deal of interest in the fundamental physics of their origins. While it is generally accepted that the novel behavior arises as a result of a combination of electronic and atomic reconstructions and growth‐induced defects, the complex interplay between these effects remains unclear. In this report, we review the progress that has been made towards unraveling the complete picture of the SrTiO3/LaAlO3 interface, focusing primarily on present ab initio theoretical work and its relation to the experimental data. In the process, we highlight some key unresolved issues and discuss how they might be addressed by future experimental and theoretical studies.
Spatial distributions of mean age and higher moments in steady continuous flows
Authors: Liu M. , Tilton J.N.
Published: April 2010

Transport equations and boundary conditions for spatial distribution of age moments in steady continuous flows are derived. Mean age is the first moment. The coefficient of variation is obtained from the second moment. Mixing‐cup averaged mean age and higher moments across the exit plane are identical to the corresponding moments of the residence‐time distribution. Numerical solutions for a 2‐D (two‐dimensional) reactor are studied and compared with those from a transient tracer equation. Agreement is excellent. Local tracer distribution function curves reveal that mean age is located on the long tail for both convection dominated short circuiting paths and diffusion dominated dead zones. Computing cost for the mean age and higher moment equations is orders of magnitude lower than that for the transient tracer concentration equation, making this mean age method an efficient tool to study mixing in steady continuous flow systems. © 2010 American Institute of Chemical Engineers AIChE J, 2010
Analysis of Cardiac Development in the TurtleEmys orbicularis(Testudines: Emidydae) using 3‐D Computer Modeling from Histological Sections
Authors: Bertens Laura M.F. , Richardson M.K. , Verbeek F.J.
Published: April 2010

In this article we present a 3‐D modeling study of cardiac development in the European pond turtle,Emys orbicularis(of the reptilian order Testudines). The study is aimed at elucidating the embryonic development of the horizontal septum in the ventricle and underscoring the importance of 3‐D reconstructions in studying morphogenesis. Turtles possess one common ventricle, partly divided into three cava by a vertical and a horizontal septum, of which the embryonic origins have so far not been described. We used serial sectioning and computerized high‐resolution 3‐D reconstructions of different developmental stages to create a chronological overview of cardiogenesis, in order to study this process. This has yielded a new understanding of the development of the horizontal septum and (directly related) the looping of the heart tube. This looping is found to be markedly different from that in the human heart, with the turtle having two clear bends in the part of the heart tube leaving the primitive ventricle, as opposed to one in humans. It is this particular looping that is reponsible for the formation of the horizontal septum. In addition to our findings on the ventricular septation this study has also yielded new insights into the developmental origins of the pulmonary vein. The 3‐D reconstructions were built using our platform TDR‐3‐D base and enabled us to study the developmental processes in specific parts of the turtle heart separately and in three dimensions, over time. The complete 3‐D reconstructions have been made available to the reader via internet using our 3‐D model browser application, which allows interactive viewing of the models. The browser application can be found on bio‐imaging.liacs.nl/galleries/emysorbicularis/TurtleGallery.html, along with additional images of both models and histological sections and animation sequences of the models. By allowing the reader to view the material in such an interactive way, we hope to make optimal use of the new 3‐D reconstruction techniques and to engage the reader in a more direct manner. Anat Rec 239:1101–1114, 2010. © 2010 Wiley‐Liss, Inc.
Conformational Studies on Peptides of α‐Aminoxy Acids with Functionalized Side‐Chains
Authors: Yang Dan , Liu Guo‐Jun , Hao Yu , Li Wei , Dong Ze‐Min , Zhang Dan‐Wei , Zhu Nian‐Yong
Published: April 2010

Peptides of homochiral α‐aminoxy acids of nonpolar side chains can form a 1.88‐helix. In this paper, we report the conformational studies of α‐aminoxy peptides 1, 2, 3, which have functionalized side chains, in both nonpolar and polar solvents. 1H NMR, XRD, and FTIR absorption studies confirm the presence of the eight‐membered‐ring intramolecular hydrogen bonds (the N‐O turns) in nonpolar solvents as well as in methanol. CD studies of peptides 1, 2, 3 in different solvents indicate that a substantial degree of helical content is retained in methanol and acidic aqueous buffers. The introduction of functionalized side chains in α‐aminoxy peptides provides opportunities for designing biologically active peptides.
Environmental dependence of five photometric band concentration indexes for luminous red galaxies from the SDSS Data Release 7
Authors: Deng X.F. , Zou S.‐Y.
Published: April 2010

Using the Luminous Red Galaxy (LRG) sample of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), we explore the environmental dependence of five photometric band concentration indexes of LRGs. It turns out that the trends for all the five band concentration indexes to change with the local density are the same: galaxies with higher concentration reside preferentially in overdense environments, while galaxies with lower concentration are located preferentially in underdense environments (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The exceptional Herbig Ae star HD 101412: The first detection of resolved magnetically split lines and the presence of chemical spots in a Herbig star
Authors: Hubrig S. , Schöller M. , Savanov I. , Gonzälez J.F. , Cowley C.R. , Schütz O. , Arlt R. , Rüdiger G.
Published: April 2010

In our previous search for magnetic fields in Herbig Ae stars, we pointed out that HD 101412 possesses the strongest magnetic field among the Herbig Ae stars and hence is of special interest for follow‐up studies of magnetism among young pre‐main‐sequence stars. We obtained high‐resolution, high signal‐to‐noise UVES and a few lower quality HARPS spectra revealing the presence of resolved magnetically split lines. HD 101412 is the first Herbig Ae star for which the rotational Doppler effect was found to be small in comparison to the magnetic splitting and several spectral lines observed in unpolarized light at high dispersion are resolved into magnetically split components. The measured mean magnetic field modulus varies from 2.5 to 3.5kG, while the mean quadratic field was found to vary in the range of 3.5 to 4.8 kG. To determine the period of variations, we used radial velocity, equivalent width, line width, and line asymmetry measurements of variable spectral lines of several elements, as well as magnetic field measurements. The period determination was done using the Lomb‐Scargle method. The most pronounced variability was detected for spectral lines of He I and the iron peak elements, whereas the spectral lines of CNO elements are only slightly variable. From spectral variations and magnetic field measurements we derived a potential rotation period Prot = 13.86 d, which has to be proven in future studies with a larger number of observations. It is the first time that the presence of element spots is detected on the surface of a Herbig Ae/Be star. Our previous study of Herbig Ae stars revealed a trend towards stronger magnetic fields for younger Herbig Ae stars, confirmed by statistical tests. This is in contrast to a few other (non‐statistical) studies claiming that magnetic Herbig Ae stars are progenitors of the magnetic Ap stars. New developments in MHD theory show that the measured magnetic field strengths are compatible with a current‐driven instability of toroidal fields generated by differential rotation in the stellar interior. This explanation for magnetic intermediate‐mass stars could be an alternative to a frozen‐in fossil field (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Eclipsing binaries in the MOST satellite fields
Authors: Pribulla T. , Rucinski S.M. , Latham D.W. , Quinn S.N. , Siwak M. , Matthews J.M. , Kuschnig R. , Rowe J.F. , Guenther D.B. , Moffat A.F.J. , Sasselov D. , Walker G.A.H. , Weiss W.W.
Published: April 2010

Sixteen new eclipsing binaries have been discovered by the MOST satellite among guide stars used to point its telescope in various fields. Several previously known eclipsing binaries were also observed by MOST with unprecedented quality. Among the objects we discuss in more detail are short‐period eclipsing binaries with eccentric orbits in young open clusters: V578 Mon in NGC 2244 and HD 47934 in NGC 2264. Long nearly‐continuous photometric runs made it possible to discover three long‐period eclipsing binaries with orbits seen almost edge‐on: HD 45972 with P = 28.1 days and two systems (GSC 154 1247 and GSC 2141 526) with P > 25 days. The high precision of the satellite data led to discoveries of binaries with very shallow eclipses (e.g., HD 46180 with A = 0.016 mag, and HD 47934 with A = 0.025 mag). Ground‐based spectroscopy to support the space‐based photometry was used to refine the models of several of the systems (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chemical recycling of polyhydroxyalkanoates as a method towards sustainable development
Authors: Ariffin Hidayah , Nishida Haruo , Hassan Mohd Ali , Shirai Yoshihito
Published: April 2010

Chemical recycling of bio‐based polymers polyhydroxyalkanoates (PHAs) by thermal degradation was investigated from the viewpoint of biorefinery. The thermal degradation resulted in successful transformation of PHAs into vinyl monomers using alkali earth compound (AEC) catalysts. Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)s (PHBVs) were smoothly and selectively depolymerized into crotonic (CA) and 2‐pentenoic (2‐PA) acids at lower degradation temperatures in the presence of CaO and Mg(OH)2 as catalysts. Obtained CA from 3‐hydroxybutyrate sequences in PHBV was copolymerized with acrylic acid to produce useful water‐soluble copolymers, poly(crotonic acid‐co‐acrylic acid) that have high glass‐transition temperatures. The copolymerization of CA derived from PHA pyrolysis is an example of cascade utilization of PHAs, which meets the idea of sustainable development.
Physicochemical properties of thiol proteinase inhibitor isolated from goat pancreas
Authors: Priyadarshini Medha , Khan Rizwan H. , Bano Bilqees
Published: April 2010

Thiol proteinase inhibitors are crucial to proper functioning of all living tissues consequent to their cathepsin regulatory and myriad important biologic properties. Equilibrium denaturation of dimeric goat pancreas thiol proteinase inhibitor (PTPI), a cystatin superfamily variant has been studied by monitoring changes in the protein's spectroscopic and functional characteristics. Denaturation of PTPI in guanidine hydrochloride and urea resulted in altered intrinsic fluorescence emission spectrum, diminished negative circular dichroism, and loss of its papain inhibitory potential. Native like spectroscopic properties and inhibitory activity are only partially restored when denaturant is diluted from guanidine hydrochloride unfolded samples demonstrating that process is partially reversible. Coincidence of transition curves and dependence of transition midpoint (3.2M) on protein concentration in guanidine hydrochloride‐induced denaturation are consistent with a two‐state model involving a native like dimer and denatured monomer. On the contrary, urea‐induced unfolding of PTPI is a multiphasic process with indiscernible intermediates. The studies demonstrate that functional conformation and stability are governed by both ionic and hydrophobic interactions. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 708–717, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Triple Hyp→Pro replacement in integramide A, a peptaib inhibitor of HIV‐1 integrase: Effect on conformation and bioactivity
Authors: De Zotti Marta , De Borggraeve Wim , Kaptein Bernard , Broxterman Quirinus B. , Singh Sheo B. , Felock Peter J. , Hazuda Daria J. , Formaggio Fernando , Toniolo Claudio
Published: April 2010

AIDS is produced by HIV‐induced infections. HIV integrase is an important enzyme as it is critical for the integration of the HIV genome into that of the host cell. This complex process is exclusively carried out by a viral enzyme not found in the host cell. Therefore, this protein represents a safe target for the development of single or combined anti‐HIV therapy. Integramide A is a 16‐mer long, effective peptaib inhibitor of HIV‐1 integrase. We have previously described a versatile synthetic strategy in solution to afford this natural compound and its diastereomer at positions 14 and 15. We also found that both peptides display a significant inhibitory activity. Here, we present our data on the synthesis in solution, in‐depth conformational analysis, and biological activity against HIV‐integrase of the analogs of the two above mentioned peptides in which all of the three (2S,4R)‐Hyp residues at positions 2, 9, and 13 are replaced by L‐Pro. This study definitely confirms that the mixed α‐/310‐ helical conformation of natural integramide A plays a key role in its mechanism of inhibition. Moreover, our data provide evidence that the amphipathic character of this helical structure is not required for the activity of integramide A against HIV‐1 integrase. These observations will hopefully help us to further clarify the precise mechanism of inhibition of this interesting peptaib and to identify shorter peptide sequences active against HIV‐1 integrase. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 96: 49–59, 2011.
Terahertz time‐domain spectroscopy of poly‐L‐lysine
Authors: Kambara Ohki , Tamura Atsuo , Uchino Takashi , Yamamoto Kohji , Tominaga Keisuke
Published: April 2010

Poly‐L‐lysine is known to have three different secondary structures depending on solvent conditions because of its flexible nature. In previous work (Kambara et al., Phys Chem Chem Phys 2008, 10, 5042‐5044), we observed two different types of structural changes in poly‐L‐lysine. In the present study, we investigated the low‐frequency spectrum of poly‐L‐lysine with a β‐sheet structure in the solid state by terahertz time‐domain spectroscopy. On the basis of this spectroscopic analysis, we found that the low‐frequency dynamics differed from those of other polypeptides. Furthermore, we performed powder X‐ray diffraction measurement on poly‐L‐lysine, which was found to be highly amorphous compared with other polypeptides. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 735–739, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Systematic review and meta-analysis of the relationship between hospital volume and outcome for lower limb arterial surgery
Authors: Awopetu A I , Moxey P , Hinchliffe R J , Jones K G , Thompson M M , Holt P J E
Published: April 2010

Background

The aim was to investigate whether a relationship existed between case volume and outcome for lower limb vascular surgical procedures.

Methods

PubMed, Embase, the Cochrane Library and Google Scholar were searched for all articles on population-based studies on the volume–outcome relationship for lower limb vascular surgery at hospital level. Outcomes were mortality and subsequent amputation after lower limb vascular surgery. The data were subjected to meta-analysis by outcome.

Results

Some 452 093 patients from ten studies were included in the systematic review and five studies were included in meta-analyses. Seven of these articles found a significant positive hospital–volume outcome relationship. The pooled effect estimate for mortality was odds ratio (OR) 0·81 (95 per cent confidence interval 0·71 to 0·91) and that for amputation was OR 0·88 (0·79 to 0·98), with better results being found after surgery at higher-volume hospitals. Significant heterogeneity was seen in the data.

Conclusion

Higher-volume hospitals were associated with reduced amputation and mortality rates after lower limb vascular surgery. These data were not as conclusive as those for other vascular surgical procedures owing to significant heterogeneity.
An educational tool for wireless sensor networks
Authors: Losilla F. , Sánchez P. , Alvarez B. , Iborra A.
Published: April 2010

The present paper introduces a tool, which simplifies the description of Wireless Sensor Networks (WSN) applications by means of a visual language and automatic generation of executable code. The tool has been used to provide non‐experienced students with a practical introduction to WSN concepts in a short period of time. Using the tool allowed students to quickly develop their own applications and test with them, focusing on their functional aspects rather than on programming and platform‐dependent matters. This has yielded good results in the adaptation to the new European Higher Education Area (EHEA) envisaged by the Bologna Process, promoting an increased role of students in education as well as improving their motivation. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 692–701, 2012
On‐line algorithm for optimal 3D path planning
Authors: Hun Chien‐Wan , Chen Hun‐Chen , Hwang Ming‐Fung
Published: April 2010

The issues of automatic car operation aiming at in an unknown complex terrain are the most effective path planning and the obstacles avoiding in this complex terrain. For that, an on‐line algorithm for guiding a mobile object in an unexplored terrain filled with convex polygonal obstacles is presented. The mobile object was taken as a point‐size auto equipped with a sensor system, which is used to detect previously all visible parts of the obstacles surrounding it. Both the visibility and the tangent graph were modified and used in this algorithm to construct the basic concept. At each stage, the next subgoal was selected from local information provided by the sensor. Furthermore, in order to expand the algorithm to handle nonconvex polygonal obstacles and mazes, it was modified by adding backtracking and by removing visited vertices. The algorithm was implemented in MATLAB language, and several numerical examples are shown to evaluate its feasibility. Moreover, the convergence of the algorithm was examined using the visibility graph, and the performance of the algorithm was evaluated by simply comparing with other algorithms for both the length of the path and the traveling time from the initial point to the target point. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 713–720, 2012