bluuebunny/crossref_metadata_2025 huggingface dataset:
Lessons from TGN1412 and TARGET: implications for observational studies and meta‐analysis
Authors: Senn Stephen
Published: April 2008

Two very different studies are examined: the first, a very large trial in osteoarthritis (the so‐called TARGET study) and the second a very small ‘first‐in‐man’ study of the monoclonal antibody TGN1412. In each trial the unbiased estimate of the treatment effect is not efficient and in con sequence the efficient estimate is not unbiased. In the case of the large trial it seems reasonable that unbiased estimation is desirable but in the case of the small trial it leads to absurd conclusions. These two cases are examined in detail and some general lessons for the analysis of clinical trials and observational studies and collections of studies are drawn. Copyright © 2008 John Wiley & Sons, Ltd.
Antioxidant and antiinflammatory activities of Sideritis perfoliata subsp. perfoliata (Lamiaceae)
Authors: Charami Maria‐Thiresia , Lazari Diamanto , Karioti Anastasia , Skaltsa Helen , Hadjipavlou‐Litina Dimitra , Souleles Christos
Published: April 2008

Sideritis perfoliata L. subsp. perfoliata is a plant widely used in folk medicine in Greece since antiquity because of its antiinflammatory, antirheumatic, antiulcer, digestive and vasoprotective properties.

Phytochemical investigations of the polar extracts afforded four flavonoid glycosides, four phenylpropanoic glycosides, caffeic acid and one iridoid, ajugoside. Reactive oxygen species (ROS) are implicated in the aetiology of several inflammatory processes. In the present study polar fractions and isolated compounds from S. perfoliata subsp. perfoliata were evaluated for their antioxidant activity using DPPH spectrophotometric and TBA lipid peroxidation assays, as well as for their antiinflammatory activity using the soybean lipoxygenase bioassay.

All extracts and isolated compounds showed significant antioxidant and inhibitory activity against soybean lipoxygenase. These findings give support to the ethnopharmacological use of the plant in the treatment of several inflammatory ailments. Copyright © 2008 John Wiley & Sons, Ltd.
Inhibitory effects of Angelicae Gigantis Radix on osteoclast formation
Authors: Kil Jong‐Seob , Kim Myung‐Gyou , Choi Hye Mi , Lim Jong‐Pil , Boo Yungmin , Kim Ee‐Hwa , Kim Jeung‐Beum , Kim Hye Kyung , Leem Kang‐Hyun
Published: April 2008

Angelicae Gigantis Radix (AGR) is one of the most widely used herbal medications. AGR is the dried root of Angelica gigas Nakai (Umbelliferae), which is known as Korean angelica. This study investigated the effects of AGR on osteoclast formation using primary bone marrow cells. TNF‐α treatment increased tartrate‐resistant acid phosphatase (Trap) positive cells and Trap activity in bone marrow cells. However, AGR significantly decreased both TNF‐α‐induced Trap positive cells and Trap activity. RT‐PCR analyses revealed that AGR decreased mRNA levels of Trap and matrix metalloproteinase‐9 in TNF‐α‐treated bone marrow cells. In addition, AGR decreased TNF‐α‐induced activation of NF‐κB. These results suggest that AGR has an inhibitory effect on the formation of osteoclasts and its effect is partially related to the NF‐κB pathway. Copyright © 2008 John Wiley & Sons, Ltd.
Antioxidative activity of geranium (Pelargonium inquinans Ait) and its active component, 1,2,3,4,6‐Penta‐O‐galloyl‐β‐d‐glucose
Authors: Piao Xiangshu , Piao Xiang‐Lan , Kim Hyun Young , Cho Eun Ju
Published: April 2008

The antioxidative activity of geranium (Pelargonium inquinans Ait) and its active component was investigated under in vitro and cellular oxidative stress models. The MeOH extract, and n‐hexane, EtOAc, BuOH and H2O fractions from geranium showed strong 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging effects and protective potential from oxidative damage by the radical generator, 2,2′‐azobis (2‐amidinopropane) dihydrochloride (AAPH) in renal epithelial LLC‐PK1 cells. In particular, the EtOAc fraction exerted the strongest antioxidative potential in not only the in vitro but also in the cellular system. It suggests that the antioxidative activity of geranium is attributed mainly to components from the EtOAc fraction. Furthermore, the active component, 1,2,3,4,6‐penta‐O‐galloyl‐β‐d‐glucose (PGG), was identified from the EtOAc fraction by the bioassay‐linked fractionation method. It displayed a potent antioxidant effect against the DPPH radical, showing an IC50 value of 1.14 µg/mL. Moreover, the compound recovered the cell viability declined by AAPH treatment significantly and dose‐dependently, implying a protective role against cellular oxidative damage. The present study suggests that geranium has an excellent antioxidative potential and that PGG from geranium is considered to be the active component with an antioxidative effect. Copyright © 2008 John Wiley & Sons, Ltd.
On the use of shear‐dependent turbulent length‐scales
Authors: Mauritsen Thorsten , Enger Leif
Published: April 2008

We investigate the behaviour of the recently proposed shear‐dependent turbulent length‐scale in the neutrally stratified surface layer. It is found that close to ground, this shear‐dependent length‐scale is proportional to height, and thus, equivalent to the law of the wall. We speculate that the law of the wall could be just a special case of applying the shear‐length to near‐surface flows. Copyright © 2008 Royal Meteorological Society
The influence of formamide (model of protein unit) on the intramolecular proton transfer in the DNA simple base guanine: A density functional theory study
Authors: Zhang An‐Guo , Zhang Hui , Zhou Zheng‐Yu , Jia Zhao‐Kun , Hou Rui‐Yan
Published: April 2008

For the purpose of investigating the influence of protein unit on the intramolecular proton transfer (IPT) reactions in the simple base guanine, a simple model (formamide) of peptides is designed to biological system investigations, and five complexes of formamide–guanine (FG1, FG2, FG3, FG4, and FG5) are determined at the B3LYP/6‐311++G(d,p) level of theory. For comparison, HF and MP2 methods are also used in this paper. The proton transfer (PT) reaction processes of guanine and FGs have been investigated employing the B3LYP/6‐311++G(d,p) level of theory. The selected thermodynamic and kinetic parameters, such as the activation energies (Ea), changes of enthalpy (ΔH) and changes of free energies (ΔG), as well as the equilibrium constants (Kp) for those reaction processes, have also been obtained by calculational means. The calculated results indicate that the assisted and protected effects of formamide on IPT in guanine are site‐dependent. CH1 is the lowest activation energy needed PT process no matter where the formamide molecule is located in. The activation energy of CH1 with formamide in S2 is the lowest one (153.3 KJ/mol), whereas the one of CH5 with formamide in S5 is the highest (318.3 KJ/mol). © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Representation of Kohn–Sham free atom eigenfunctions by Slater‐type orbitals
Authors: Romanowski Zbigniew , Jalbout Abraham F.
Published: April 2008

Slater‐type orbitals are applied to represent the numerically obtained Kohn–Sham eigenfunction of free atom. The algorithm evaluating the nonlinear expansion coefficients of this approximation is described. Standard iterative solution of Kohn–Sham equation to obtain the nonlinear expansion coefficients is avoided and replaced by the projection method. First, the eigenfunction is obtained in the B‐spline space based on the Galerkin formulation of the finite element method. Then, based on the density functional theory, the conditions are formulated, which leads to the set of nonlinear equations. The proposed algorithm is general and can be applied for any atomic Kohn–Sham eigenfunction. As an examplary application of the proposed algorithm, the set of nonlinear equations is derived for occupied states of N, Al, Ga, and In atoms. The expansion coefficients, obtained for these atoms, are evaluated numerically by Newton procedure and listed in the tables. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Test and modification of the van der Waals' radii employed in the default PCM model
Authors: Mu Wei‐Hua , Chasse Gregory Adam , Fang De‐Cai
Published: April 2008

High level ab initio calculations at the B3LYP/6‐311++G(d,p) and MP2(full)/6‐311++G(d,p) levels employing PCM/UA0 model with different van der Waals' radii for the systems that contain lithium atoms have been carried out, in order to see if the van der Waal's radius for lithium atom employed in the default PCM/UA0 model is proper or not. Comparative analysis indicated that the van der Waals' radius for alkali metals, especially for lithium atom in the default PCM/UA0 model within the Gaussian 03 package, is too small, which causes erroneous redundant imaginary frequencies (RIFs) in the characterization of Li‐containing compounds from moderate to big size. A new set of van der Waals' atomic radii based on QTAIM, proposed by Bader, was suggested for a better choice in the characterization of compounds containing alkali metals, for which it can effectively avoid the erroneous RIFs for corresponding geometries of these Li‐containing systems. © 2008 Wiley Periodicals, Inc. Int. J. Quantum Chem, 2008
How to get more mileage from randomness extractors
Authors: Shaltiel Ronen
Published: April 2008

Let 𝒞 be a class of distributions over Bn. A deterministic randomness extractor for 𝒞 is a function E : BnarBm such that for any X in 𝒞 the distribution E(X) is statistically close to the uniform distribution. A long line of research deals with explicit constructions of such extractors for various classes 𝒞 while trying to maximize m.

In this paper we give a general transformation that transforms a deterministic extractor E which extracts “few” bits into an extractor E′ that extracts “almost all the bits present in the source distribution.” More precisely, we prove a general theorem saying that if E and 𝒞 satisfy certain properties, then we can transform E into an extractor E′.

Our methods build on (and generalize) a technique of Gabizon et al. [FOCS (2004) 394–403] that presents such a transformation for the very restricted class 𝒞 of “oblivious bit‐fixing sources.” The high level idea is to find properties of E and 𝒞 which allow “recycling” the output of E so that it can be “reused” to operate on the source distribution. An obvious obstacle is that the output of E is correlated with the source distribution.

Using our transformation we give an explicit construction of a two‐source extractor E : Bn × BnarBm such that for every two independent distributions X1 and X2 over Bn with min‐entropy at least k = (1/2 + δ)n and eps ≤ 2, E(X1,X2) is eps‐close to the uniform distribution on m = 2k ‐ Cδ log(1/eps) bits. This result is optimal except for the precise constant Cδ and improves previous results by Chor and Goldreich [SICOMP 17 (1988) 230–261], Vazirani [Combinatorica 7 (1987) 375–392], and Dodis et al. [RANDOM (2004) 334–344].

We also give explicit constructions of extractors for samplable distributions that extract many bits even out of “low‐entropy” samplable distributions. These constructions rely on average case hardness assumptions and extend some previous results by Trevisan and Vadhan [FOCS (2000) 32–42] which give such extractors only for distributions with “high entropy.” © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008
Perfect simulation with exponential tails on the running time
Authors: Huber Mark
Published: April 2008

Monte Carlo algorithms typically need to generate random variates from a probability distribution described by an unnormalized density or probability mass function. Perfect simulation algorithms generate random variates exactly from these distributions, but have a running timeTthat is itself an unbounded random variable. This article shows that commonly used protocols for creating perfect simulation algorithms, such as Coupling From the Past can be used in such a fashion that the running time is unlikely to be very much larger than the expected running time. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008
Enquiring into skills development with SSM: a South African experience
Authors: Córdoba José‐Rodrigo , Farquharson Fiona
Published: April 2008

Since the first democratic elections in 1994, vocational education and training (VET) in South Africa has undergone major changes in order to equip the country to enhance its skills base, and to face post apartheid and globalization challenges. Part of the change has involved the adoption (by some players) of ‘Mode 2’ ideas of knowledge production as suggested by Gibbons and those studying the sociology of knowledge in modern societies. Mode 2 production is trans‐disciplinary and uses socially accountable forms to generate scientific knowledge in contrast to ‘Mode 1’ which is mainly based on single scientific disciplines and knowledge generation by the scholarly community. The objective of this adoption in the South African context is to enable a variety of stakeholders to be involved both in enhancing research in South Africa and responding to the needs of different economic sectors. However, the dynamics of stakeholder interaction can be complex. In this paper, we report on a skills capacity building intervention involving the application of Systems Thinking approaches and methodologies in a South African setting. Our intervention was informed by the use of soft systems methodology (SSM) as a means of assisting different groups of researchers firstly to share their perceptions about research in the skills development context, and secondly to collaborate together in generating suggestions for improvements. A key objective was to improve the interactions between researchers and other stakeholders in the organization of skills development research projects. The use of SSM methodology enabled us to ‘qualify’ the nature of these interactions. It also gave us clues about particular issues (e.g. power) that need to be tackled to improve capacity building in this area. Copyright © 2008 John Wiley & Sons, Ltd.
Adapting organizations: the instance of business process re‐engineering
Authors: Dekkers Rob
Published: April 2008

The question whether the often‐radical approach of Business Process Re‐engineering constitutes a viable option for restructuring is at the heart of this study. It appraises the case of Business Process Re‐engineering and its kin—process innovation and the Delft School Approach—from an evolutionary perspective based on an analogy between organisms and organizations. The research introduces a reference model that originates in evolutionary biological theories and models. The study undertaken—archival research for Business Process Re‐engineering and process innovation, and six case studies for the Delft School Approach—confirms that organizations evolve slower than expected, that Business Process Re‐engineering as a radical approach is hardly viable, that it and its kin seem to be directed at optimization and that the initiatives hardly connect to external opportunities. The primary yield of this research is the reference model that makes it possible to describe these (often slower) evolutionary processes. Copyright © 2008 John Wiley & Sons, Ltd.
Toward a property based requirements theory: System requirements structured as a semilattice
Authors: Micouin Patrice
Published: April 2008

In this paper, we outline a property‐based requirement (PBR) theory. After introducing the mathematical notion of semilattice, we express the ontological and epistemological assumptions on which our theory is built. We provide a definition of a “well formed (wf‐)requirement,” based on the property concept, distinguished from that of an “expectation.” Then, we introduce two relationships between wf‐requirements called respectively “conjunction” operation and “stringency” relationship. So, we state that a set of wf‐requirements, assigned to a system, is structured as a semilattice and that the maximum element of this semilattice matches the system specification. The network including all the expectations and wf‐requirements related to a system are linked together through two very unlike categories of relationships. “De dicto” relationships are linguistic dependencies while “de re” relationships among requirements are extralinguistic dependencies among material properties refereed by wf‐requirements. We highlight two types of “de re” relationship among wf‐requirements. The first one is the well known “derivation” relationship that links together a “parent” requirement with its “child” requirements during the system design process. We introduce a second one, called “coupling” relationship. Wf‐requirements are coupled when the change of one of them collides with others. We claim that our PBR theory belongs to the same paradigm as the model‐based systems engineering (MBSE) approaches whereas TBR belongs to the same field as empirical design approaches. Then, we relate our requirements formulation to features of the OMG SysMLTM language. We conclude on our prospects for research, which connect our requirement theory with reflections carried out on the bodies of knowledge and their specification, i.e. ontologies. © 2008 Wiley Periodicals, Inc. Syst Eng
Thirty years of advocacy in San Francisco: Lessons learned and the next generation of leadership
Authors: Lee NTanya
Published: April 2008

Professional advocacy organizations are often challenged by the question of their authentic community representation and their ability to balance short‐term pragmatism with strategic plans for long‐term, systemic change. Coleman Advocates, one of the nation's most effective child advocacy organizations, has taken up this challenge under the leadership of a next‐generation leader of color who followed a dynamic director of the baby boom generation. In this piece, Coleman's thirty years of social change strategies are analyzed from the perspective of this new executive director, who has facilitated the latest organizational shift that deepens its commitment to building bottom‐up grassroots leadership and community power while keeping the best of the professional, staff‐led advocacy model. Issues of race, accountability, power, and movement building are addressed through the lens of one organization's evolution, with the goal of building a long‐term movement that will achieve racial and economic equity for all children and families.
The development of collective moral leadership among parents through education organizing
Authors: Evans Michael P. , Shirley Dennis
Published: April 2008

It is often assumed that parent participation in schools is primarily based on self‐interest and that this is a frequent source of contention between parents and teachers. This article examines the experiences of members of the Jamaica Plain Parent Organizing Project (JP‐POP), a community‐based organization in Boston, and reveals that some parents have learned to act beyond their individual self‐interest and to organize on behalf of the entire community as a result of their participation. The authors present qualitative data from interviews with JP‐POP members to ascertain the motivations behind their initial decisions to become involved in education, the benefits they derive from their participation, and the gradual evolution of narrow definitions of self‐interest to more communal understandings. Finally, they draw out implications for the potential capacity enhancement of community‐based organizations in education at both the institutional and district levels.
Parkin‐co‐regulated gene (PACRG) product interacts with tubulin and microtubules
Authors: Ikeda Takashi
Published: April 2008

MINT‐6439731, MINT‐6439753, MINT‐6439768:

PACRG (genbank_protein_gi:169219363), tubulin alpha (uniprotkb:P02550), tubulin beta (uniprotkb:Q2XVP4) bind (MI:0407) by cosedimentation (MI:0027)

MINT‐6439796:

PACRG (genbank_protein_gi:169219363), tubulin alpha (uniprotkb:P02550), tubulin beta (uniprotkb:Q2XVP4) bind (MI:0407) by pull-down (MI:0096)
Mapping of interaction domains of putative telomere‐binding proteins AtTRB1 and AtPOT1b from Arabidopsis thaliana
Authors: Schrumpfová Petra Procházková , Kuchař Milan , Paleček Jan , Fajkus Jiří
Published: April 2008

MINT‐6440051:

AtTRB1 (uniprotkb:Q8VWK4) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by two‐hybrid (MI:0018)

MINT‐6440068:

AtTRB2 (uniprotkb:Q8VX38) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by two‐hybrid (MI:0018)

MINT‐6440083:

AtTRB3 (uniprotkb:Q9M2X3) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by two‐hybrid (MI:0018)

MINT‐6440099:

AtPOT1b (uniprotkb:Q6Q835) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by two‐hybrid (MI:0018)

MINT‐6440119:

AtPOT1b (uniprotkb:Q6Q835) physically interacts (MI:0218) with AtTRB2 (uniprotkb:Q8VX38) by two‐hybrid (MI:0018)

MINT‐6440138:

AtPOT1b (uniprotkb:Q6Q835) physically interacts (MI:0218) with AtTRB3 (uniprotkb:Q9M2X3) by two‐hybrid (MI:0018)

MINT‐6440216:

AtPOT1b (uniprotkb:Q6Q835) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by coimmunoprecipitation (MI:0019)

MINT‐6440157:

AtTRB2 (uniprotkb:Q8VX38) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by coimmunoprecipitation (MI:0019)

MINT‐6440177:

AtTRB3 (uniprotkb:Q9M2X3) physically interacts (MI:0218) with AtTRB1 (uniprotkb:Q8VWK4) by coimmunoprecipitation (MI:0019)
Epigenetics and cancer, 2nd IARC meeting, Lyon, France, 6 and 7 December 2007
Authors: Lambert Marie-Pierre , Herceg Zdenko
Published: April 2008

It is becoming widely accepted that epigenetic alterations are universally present in human malignancies and that cancer is as much a disease of abnormal epigenetics as it is a genetic disease. The potential utility of epigenetics and epigenomics in cancer research and cancer control is highlighted by the fact that many funding agencies put cancer epigenetics on the priority list. The goal of this meeting, held at the offices of the International Agency for Research on Cancer in Lyon, France, 6 and 7 December 2007, was to discuss recent conceptual and technological advances in cancer epigenetics and epigenomics, the future research needs in the field, and their implications for early detection, risk assessment and prevention of cancer.

While epigenetics has been historically linked to phenomena that do not follow normal genetic principles of heritability, recent mechanistic advances have begun to change our understanding of complex diseases including cancer, traditionally viewed as genetic in origin. It is now known that epigenetic mechanisms play critical roles in regulation of many cellular functions and their deregulation may disrupt the control of fundamental processes leading to tumour formation. A flurry of screening and functional studies revealed that most key processes found in cancer cells, such as silencing of tumour suppressor genes, activation of oncogenes, aberrant cell cycle processes, defects in DNA repair, and deregulation of cell death, can be triggered by epigenetic deregulation. Two important features that distinguish epigenetic changes from genetic alterations are the gradual appearance and reversibility of epigenetic events. These features make epigenetic alterations an attractive target for therapeutic intervention and the development of preventive strategies. For example, aberrant patterns of DNA methylation and histone acetylation and methylation can be targeted by drugs aiming to re‐activate epigenetically silenced genes. Until now, most studies on epigenetic changes in cancer were generally focused on specific genes. However, this meeting also stressed the need to take advantage of recent progress in epigenomics and emergence of powerful technologies for detection of epigenetic changes in high throughput and genome‐wide settings. This may further advance our capacity to evaluate the contribution of epigenetic changes induced by environmental epimutagens to human cancer. This information may prove critical for the design of efficient strategies for early diagnosis, therapy, and prevention of cancer.
Generalized Euler constants
Authors: DIAMOND HAROLD G. , FORD KEVIN
Published: April 2008

We study the distribution of a family $\{\g(\P)\}$ of generalized Euler constants arising from integers sieved by finite sets of primes $\P$. For $\P=\P_r$, the set of the first r primes, $\g(\P_r) \to \exp(-\g)$ as r → ∞. Calculations suggest that $\g(\P_r)$ is monotonic in r, but we prove it is not. Also, we show a connection between the distribution of $\g(\P_r) - \exp(-\g)$ and the Riemann hypothesis.
Coping bei Frauen mit Brustkrebs im perioperativen Bereich – Selbst- und Fremdeinschätzung
Authors: Holtgräwe Martina , Pinkert Christiane , Remmers Hartmut
Published: April 2008

Über die Krankheitsverarbeitung von Frauen mit Brustkrebs in der perioperativen Phase und die Fähigkeit der Pflegenden, diese Verarbeitung einzuschätzen, ist wenig bekannt. Mithilfe der Selbst- und Fremdratingversion der Berner Bewältigungsformen (BEFO) wurde die Krankheitsverarbeitung von 42 Brustkrebspatientinnen noch während des stationären Aufenthalts erhoben. Es wurden zwei Fremdratings durchgeführt, zum einen von betreuenden Pflegenden auf Grundlage ihrer täglichen Pflege und zum anderen von zwei Forscherinnen anhand eines halbstrukturierten Interviews. Die Teilnehmerinnen erhielten den Fragebogen der BEFO- Selbstratingversion. Die Pflegenden und die Projektmitarbeiterinnen schätzten ebenso wie die Patientinnen Zuwendung (H(A) 90,5–100%), Zupacken (H(A) 66,7–100%), Passive Kooperation (H(A) 59,5–100%) und Akzeptieren/Stoizismus (H(A) 64,3–97,6%) als stärkste Copingformen ein. Im Rating der Forscherinnen nehmen Dissimulieren, Isolieren/Unterdrücken und im Pflegerating Altruismus einen höheren Rang ein als im Selbstrating. Einige Bewältigungsformen zeigen eine deutliche Altersabhängigkeit. Die Diskrepanzen in den Rangfolgen der Ratingversionen von Pflegenden und Patientinnen werden anhand von empirischen Befunden zum Kommunikationsgeschehen zwischen Pflegenden und Patientinnen diskutiert.
Präoperative Massnahmen und Abklärungen - Ein Update
Authors: Zalunardo M. P. , Spahn D. R.
Published: April 2008

Die Krankenhausaufenthaltsdauer wird immer kürzer, und immer mehr Patienten werden in der ambulanten Sprechstunde vom Anästhesisten beurteilt und aufgeklärt. Die präoperativen Untersuchungen werden immer häufiger ambulant gemacht, oder die Untersuchungsresultate werden bereits vom Hausarzt mitgebracht. Es besteht nach wie vor ein Trend zu weniger und selektiveren Abklärungsuntersuchungen. Der Wert der viel zitierten Abklärungsalgorithmen ist heute umstritten. Zudem sind diese meist komplexen Schemata im Einzelfall nicht immer hilfreich. Die perioperative medikamentöse Kardioprotektion mittels Betablocker und Statinen und die Weiterführung der Behandlung mit Plättchenhemmern bei Patienten mit koronaren Stents scheinen einen grossen Stellenwert in der Reduktion von kardialen Ereignissen zu haben. Ein sorgfältig erhobener Status praesens und eine gezielte Anamneseerhebung haben auch heute noch nicht an Bedeutung verloren und tragen wesentlich zur Effizienz der präoperativen Abklärung bei.
Die Anatomie eines Miniaturschädelmodells - Visualisierung der Anthropologie Leonardo da Vincis
Authors: Ahner E.
Published: April 2008

Vorgestellt wird ein aussergewöhnliches Exemplar eines Miniaturschädels unbekannter Provenienz. Die anatomische Detaillierungstiefe, ausgeführt in hervorstechender Kunstfertigkeit, erinnert an die Schädelstudien Leonardo da Vincis und verlangt eine über den emblematischen Charakter des «memento mori» hinausgehende Interpretation. In Anlehnung an die vielfältigen Themenfelder seiner Schädelstudien wird eine anatomischanthropologische Deutung vorgeschlagen. Dieses Vorhaben erfordert die Zusammenführung von Kunstgeschichte, Medizingeschichte und Anthropologie. Im Blick auf einige Unstimmigkeiten in der anatomischen Ausführung ist eine mögliche Pathologie in Diskussion, darüber hinaus die Visualisierung eines historischen Konzepts der Hirnfunktion.
Nonlocality of Atlantic tropical cyclone intensities
Authors: Swanson Kyle L.
Published: April 2008

The assumption that tropical cyclones respond primarily to sea surface temperatures (SSTs) local to their main development regions underlies much of the concern regarding the possible impacts of anthropogenic greenhouse warming on tropical cyclone statistics. Here the observed relationship between changes in sea surface temperature and tropical cyclone intensities in the Atlantic basin is explored. Atlantic tropical cyclone intensity fluctuations and storm numbers are shown to depend not only upon SST anomalies local to the Atlantic main development region, but also in a negative sense upon the tropical mean SST. This behavior is shown in part to be consistent with changes in the tropical cyclone potential intensity that provides an upper bound on storm intensity. However, Atlantic tropical cyclone intensity fluctuations are more nonlocal than the potential intensity itself and specifically vary along with Atlantic main development region SST anomalies relative to the tropical mean SST. This suggests that there is no straightforward link between warmer SSTs in the main development region and more intense tropical cyclones.
TREMOrEC: A software utility for automatic classification of volcanic tremor
Authors: Masotti M. , Campanini R. , Mazzacurati L. , Falsaperla S. , Langer H. , Spampinato S.
Published: April 2008

We describe a stand‐alone software utility named TREMOrEC, which carries out training and test of a Support Vector Machine (SVM) classifier. TREMOrEC is developed in Visual C++ and runs under Microsoft Windows operating systems. Ease of use and short time processing, along with the excellent performance of the SVM classifier, make this tool ideal for volcano monitoring. The development of TREMOrEC is motivated by the successful application of the SVM classifier to volcanic tremor data recorded at Mount Etna in 2001. In that application, spectrograms of volcanic tremor were divided according to their recording date into four classes associated with different states of activity, i.e., pre‐eruptive, lava fountain, eruptive, or post‐eruptive. During the training, SVM learned the a priori classification. The classifier's performance was then evaluated on test sets not considered for training. The classification results matched the actual class membership with an error of less than 6%.
Sensitivity of Southern Hemisphere climate to zonal asymmetry in ozone
Authors: Crook Julia A. , Gillett Nathan P. , Keeley Sarah P. E.
Published: April 2008

Climate model simulations of past and future climate invariably contain prescribed zonal mean stratospheric ozone. While the effects of zonal asymmetry in ozone have been examined in the Northern Hemisphere, much greater zonal asymmetry occurs in the Southern Hemisphere during the break up of the Antarctic ozone hole. We prescribe a realistic three‐dimensional distribution of ozone in a high vertical resolution atmospheric model and compare results with a simulation containing zonal mean ozone. Prescribing the three dimensional ozone distribution results in a cooling of the stratosphere and upper troposphere comparable to that caused by ozone depletion itself. Our results suggest that changes in the zonal asymmetry of ozone have had important impacts on Southern Hemisphere climate, and will continue to do so in the future.
On the estimation of seismic intensity in earthquake early warning systems
Authors: Yamamoto Shunroku , Rydelek Paul , Horiuchi Shigeki , Wu Changjiang , Nakamura Hiromitsu
Published: April 2008

The infamous Tokai Earthquake, which by some accounts is overdue, is expected to be a magnitude ≥ 8 event that will cause unprecedented damage in regions of Japan. To mitigate hazards from large earthquakes in Japan, an earthquake early warning (EEW) system was developed that is able to determine hypocentral locations from P‐arrival data within a few seconds and then transmit this information before the onset of large ground motions from the later arrival of S‐waves. We introduced a new source parameter for seismic intensity magnitude that can be estimated from the real‐time P‐wave data during the early stages of fault rupture for most earthquakes M ≥ 6.5. The use of this parameter results in a significant improvement in the uncertainty in the estimated seismic intensity compared to estimates derived from earthquake magnitude. A pre‐established relation between the P‐ and S‐wave seismic intensity therefore enables an EEW system to issue a rapid and reasonably reliable prediction of the amount of ground shaking that may be expected from the damaging S‐waves.
Solar wind excitation of Pc5 fluctuations in the magnetosphere and on the ground
Authors: Kessel R. L.
Published: April 2008

The primary purpose of this paper is to show the importance of solar wind excitation as a source of magnetospheric and ground Pc5 fluctuations. In particular, we show that pressure fluctuations, a nearly ubiquitous feature of the solar wind, drive magnetospheric compressional Pc5, whose amplitude and power increase in direct proportion to the amplitude and power of the solar wind pressure fluctuations. Previous studies of compressional Pc5 have focused primarily on internally generated waves on the dusk flank; here we highlight the pressure fluctuations associated with geoeffective high‐speed streams (HSSs) and interplanetary coronal mass ejections (ICMEs) during a time interval in March and April 2002, in the declining phase of the solar cycle, when there was a favorable alignment of satellites. Using three examples and a statistical survey, we show that for this time interval external forcing due to solar wind dynamic pressure fluctuations was dominant over internal forcing. Fluctuations driven by internal processes, occurring primarily at dusk and on the nightside, accounted for less than 20% of the total power. We also found that multiple external forcing processes were occurring during this interval, including evanescent propagation of compressional waves, field line resonance (FLR), and global mode excitation. We need to enlarge our vision of the source of ULF waves to include excitation by solar wind pressure fluctuations as a significant factor.
Analysis of thermospheric response to magnetospheric inputs
Authors: Deng Yue , Maute Astrid , Richmond Arthur D. , Roble Ray G.
Published: April 2008

The influence of the high‐latitude energy inputs and heating distributions on the global thermosphere are investigated by coupling a new empirical model of the Poynting flux with the NCAR‐TIEGCM. First, in order to show the contribution of the electric field variability to the energy input and thermospheric temperature, model results are compared for simulations where Joule heating is calculated with the average electric field (called “simple Joule heating”) and where Joule heating is adjusted according to the Poynting flux from the empirical model. In the northern (summer) hemisphere, the Poynting flux has a peak in the dayside cusp, which is missing in the altitude‐integrated simple Joule heating. The hemispheric integral of the Poynting flux is approximately 30% larger than the integral of simple Joule heating, and the polar average (poleward of 40°) temperature calculated with the Poynting flux increases by 85–95 K, which is more than 50% of the temperature increase caused by the polar energy inputs. Second, three different methods to distribute the Poynting flux in altitude are investigated. Different heating distributions cause a difference in the polar average of heating per unit mass as high as 40% at 160 km altitude. Consequently, the difference of the polar average temperature among these three cases is close to 30–50 K. These results suggest that not only the total amount of energy input, but the way that the energy is distributed in altitude is significant to the impact of the magnetosphere on the thermosphere and ionosphere.
The 2.5‐D analytical model of steady‐state Hall magnetic reconnection
Authors: Korovinskiy D. B. , Semenov V. S. , Erkaev N. V. , Divin A. V. , Biernat H. K.
Published: April 2008

An analytical model of steady‐state magnetic reconnection in a collisionless incompressible plasma is developed using the electron Hall MHD approximation. It is shown that the initial complicated system of equations may be split into a system of independent equations, and the solution of the problem is based on the solution of the Grad‐Shafranov equation for a magnetic potential. This equation is found to be fundamental for the whole problem analysis. An electric field potential jump across the electron diffusion region and the separatrices is proved to be the necessary condition for steady‐state reconnection. Besides of this fact, it is found that the protons in‐plane motion obeys to Bernoulli law. The solution obtained demonstrates all essential Hall reconnection features, namely proton acceleration up to Alfvén velocities and the formation of Hall current systems and a magnetic field structure as expected.
Stacked jets in the deep equatorial Atlantic Ocean
Authors: Eden Carsten , Dengler Marcus
Published: April 2008

Middepth current measurements in the equatorial Atlantic are characterized by elevated levels of energy contained in zonal flows of high baroclinic mode number. These alternating zonal flows, often called equatorial stacked jets, have amplitudes up to 20 cm s−1and vertical wavelengths of 600 m. The jets are most pronounced in the depth range between 500 and 2500 m. Repeated direct velocity observations at 35°W indicate that the jets are coherent within ±1° of the equator. Individual jets can persist for 1–2 years, but they appear and decay rather irregularly. The equatorial stacked jets are also found in realistic general circulation model simulations. The features grow in amplitude with increasing horizontal and vertical model resolution. However, even at very high model resolutions, their amplitudes are still underestimated. In all model simulations, high levels of energy related to the stacked jets are found in the vicinity of the western boundary currents (WBCs). Depth range and strength of the WBCs in different experiments are related to depth range and strength of the jets. In the interior, stacked jets are characterized by eastward wave propagation suggesting that high baroclinic mode Kelvin waves radiate energy generated in the WBC into the interior and form the stacked jets.
Spatial and temporal variations of the Kuroshio east of Taiwan, 1982–2005: A numerical study
Authors: Hsin Yi‐Chia , Wu Chau‐Ron , Shaw Ping‐Tung
Published: April 2008

A 1/8° East Asian Marginal Seas model nested to a larger‐domain North Pacific Ocean model is implemented over a span of 24 years from 1982 to 2005 to investigate the spatial and temporal variations of the Kuroshio east of Taiwan. Between 22 and 25°N, the mean state and variability of the Kuroshio, such as the two paths observed in the trajectories of surface drifters southeast of Taiwan and the branching of the Kuroshio northeast of Taiwan, are well reproduced by the model. Southeast of Taiwan, the Kuroshio is mostly in the top 300 m in the inshore path but extends to 600 m in the offshore path. Northeast of Taiwan, the Kuroshio follows the shelf edge in the East China Sea but may branch along a path south of the Ryukyu Islands. The latter path often meanders southward, and a significant portion of the Kuroshio transport may be diverted to this path. The Kuroshio extends from the coast to 123–123.5°E between 22 and 25°N with currents reaching a depth of 1000 m at some latitudes. The Kuroshio transports averaged over five sections east of Taiwan are 28.4 ± 5.0 Sv and 32.7 ± 4.4 Sv with and without the contribution from the countercurrent, respectively.
Modeling lava lake heat loss, rheology, and convection
Authors: Harris Andrew J. L.
Published: April 2008

Measurements at Erta Ale's lava lake and theoretical equations for lake rheology, density driven convection and thermally‐driven plume ascent allow the constraint of lake dynamics. Cooling and crystallization expected from surface heat losses imply a viscosity increase from 150 Pa s to 300–1800 Pa s for cooled surface layers. Convection is expected to proceed vigorously under low viscosity conditions driving rapid (0.1–0.4 m s−1) surface motions and sluggishly under moderate‐to‐high viscosity conditions to drive slower motions (<0.08 m s−1). Convection is likely driven by small (∼6 kg m−3) density differences, where surface cooling can influence lake rheology and explain variable rates of surface convective motion.
Ballooning mode waves prior to substorm‐associated dipolarizations: Geotail observations
Authors: Saito M. H. , Miyashita Y. , Fujimoto M. , Shinohara I. , Saito Y. , Liou K. , Mukai T.
Published: April 2008

We present in situ observations consistent with the ballooning mode in the vicinity of the magnetic equator at XGSM = −10 to −13 RE prior to substorm‐associated dipolarization onsets. The ballooning instability is expected to have a wavevector along the Y direction and to give variation to the curvature of the ambient magnetic field lines. The magnetic field fluctuations appearing in the Bx component are transported by the ambient plasma drift in the Y direction. A discrete frequency band would be identified in time series data if the mode has a discrete wavelength. The ballooning mode of this property was identified at the magnetic equator a few min before dipolarization onsets only when the plasma β was large (20 to 70). Using low‐energy ion velocity data, we show that the mode has almost zero frequency in the plasma rest frame so that ωsc ∼ ky · vy, where ωsc is the frequency in the spacecraft frame, and ky and vy are the wavenumber and the ambient plasma flow in the Y direction, respectively. This enables us to estimate the wavelengths of the ballooning mode, which were found to be of the order of the ion Larmor radius.
An improved bathymetric portrayal of the Arctic Ocean: Implications for ocean modeling and geological, geophysical and oceanographic analyses
Authors: Jakobsson Martin , Macnab Ron , Mayer Larry , Anderson Robert , Edwards Margo , Hatzky Jörn , Schenke Hans Werner , Johnson Paul
Published: April 2008

A digital representation of ocean floor topography is essential for a broad variety of geological, geophysical and oceanographic analyses and modeling. In this paper we present a new version of the International Bathymetric Chart of the Arctic Ocean (IBCAO) in the form of a digital grid on a Polar Stereographic projection with grid cell spacing of 2 × 2 km. The new IBCAO, which has been derived from an accumulated database of available bathymetric data including the recent years of multibeam mapping, significantly improves our portrayal of the Arctic Ocean seafloor.
The Epithelial Membrane Protein 1 is a Novel Tight Junction Protein of the Blood—Brain Barrier
Authors: Bangsow Thorsten , Baumann Ewa , Bangsow Carmen , Jaeger Martina H , Pelzer Bernhard , Gruhn Petra , Wolf Sabine , von Melchner Harald , Stanimirovic Danica B
Published: April 2008

In the central nervous system, a constant microenvironment required for neuronal cell activity is maintained by the blood—brain barrier (BBB). The BBB is formed by the brain microvascular endothelial cells (BMEC), which are sealed by tight junctions (TJ). To identify genes that are differentially expressed in BMEC compared with peripheral endothelial cells, we constructed a subtractive cDNA library from porcine BMEC (pBMEC) and aortic endothelial cells (AOEC). Screening the library for differentially expressed genes yielded 26 BMEC-specific transcripts, such as solute carrier family 35 member F2 (SLC35F2), ADP-ribosylation factor-like 5B (ARL5B), TSC22 domain family member 1 (TSC22D1), integral membrane protein 2A (ITM2A), and epithelial membrane protein 1 (EMP1). In this study, we show that EMP1 transcript is enriched in pBMEC compared with brain tissue and that EMP1 protein colocalizes with the TJ protein occludin in mouse BMEC by coimmunoprecipitation and in rat brain vessels by immunohistochemistry. Epithelial membrane protein 1 expression was transiently induced in laser-capture microdissected rat brain vessels after a 20-min global cerebral ischemia, in parallel with the loss of occludin immunoreactivity. The study identifies EMP1 as a novel TJ-associated protein of the BBB and suggests its potential role in the regulation of the BBB function in cerebral ischemia.
Metabolic Origin of Bold Signal Fluctuations in the Absence of Stimuli
Authors: Fukunaga Masaki , Horovitz Silvina G , de Zwart Jacco A , van Gelderen Peter , Balkin Thomas J , Braun Allen R , Duyn Jeff H
Published: April 2008

Blood oxygen level-dependent (BOLD) functional magnetic resonance imaging studies have shown the existence of ongoing blood flow fluctuations in the absence of stimuli. Although this so-called ‘resting-state activity’ appears to be correlated across brain regions with apparent functional relationship, its origin might be predominantly vascular and not directly representing neuronal signaling. To investigate this, we simultaneously measured BOLD and perfusion signals on healthy human subjects ( n = 11) and used their ratio (BOLD/perfusion ratio or BPR) as an indicator of metabolic demand. BPR during rest and sleep was compared with that during a visual task (VT) and a breath-holding task (BH), which are challenges with substantial and little metabolic involvement, respectively. Within the visual cortex, BPR was 3.76 ± 1.23 during BH, which was significantly higher than during the VT (1.76 ± 0.27) and rest (1.56 ± 0.41). Meanwhile, BPR values during VT and rest were not significantly different, suggesting a similar metabolic involvement. Eight subjects showed stage 1 and 2 sleep, during which temporally correlated BOLD and perfusion activity continued. In these subjects, there was no significant difference in BPR between the sleep and waking conditions (1.79 ± 0.54 and 1.66 ± 0.67, respectively), but both were lower than the BPR during BH. These data suggest that resting-state activity, at least in part, represents a metabolic process.
Idiosyncratic evolution of conserved eukaryote proteins that are similar in sequence to archaeal or bacterial proteins
Authors: Britten Roy
Published: April 2008

Sequence comparisons have been made between the proteins of 571 prokaryote species including 46 archaea and 525 bacteria and the set of human proteins. Highly conserved eukaryotic proteins are often strikingly similar in sequence to archaeal and bacterial proteins. Yet in many cases similarity to archaeal proteins is not correlated to the similarity to bacterial proteins. In these comparisons there are hundreds of eukaryote proteins that match well archeal proteins, but do not match recognizably to bacterial proteins, while thousands of proteins match well to bacterial proteins but not recognizably to archeal proteins. Forty percent of the 21,440 human proteins that significantly match prokaryote proteins are in this extreme idiosyncratic category. These relationships have been preserved over billions of years since the last common ancestor or sharing of protein genes between prokaryotes and eukaryotes. For each of the 21,440 members of this set of human proteins (that make significant matches to any of the 1.8 million proteins in this set of prokaryote species protein libraries) it is certain that each protein has important functions both in prokaryotes and eukaryotes and the precursor proteins have been important in the precursor species of both. That is the only explanation for the preservation of amino acid sequence similarity for the billions of years since the last common ancestor or period of sharing of proteins. Comparisons were made between the proteins of Arabidopsis thaliana and Saccharomyces cerevisiae to the proteins of the 571 prokaryote species. The results agreed with the human comparisons indicating that the conclusions apply to eukaryotes generally.