bluuebunny/crossref_metadata_2025 huggingface dataset:
Ki‐67 labeling: A more sensitive indicator of malignant phenotype than mitotic count or tumor size?
Authors: Lowe Kevin , Khithani Amit , Liu Elizabeth , Winston Tanyss , Christian Derrick , Saad Joe , Jeyarajah Dhiresh Rohan
Published: May 2012

Background and Objectives

The Ki‐67 index has been incorporated into The World Health Organization's classification system of pancreatic neuroendocrine tumors. However, pathologists continue to question the utility of Ki‐67 index over that of mitotic count as an indicator of proliferative activity. The intent of the current study is to compare K‐i67 index with tumor size and mitotic rate for the association of each with lymph node metastasis and survival.

Methods

The current study is a review of 24 patients with pancreatic neuroendocrine tumors.

Results

Regional LNM were present in 100% of tumors with Ki‐67 index >10%, while only 25% of tumors with <10% Ki‐67 had LNM (P = 0.003). No tumors <2 cm had >10% Ki‐67 labeling. Of patients with tumors showing ≥10% Ki‐67 labeling, 80% died during the observation period of this study, while during the same time period, no patients with <10% Ki‐67 labeling died.

Conclusion

Ki‐67 index of >10% is a sensitive indicator of malignant behavior and mortality. Future advances in management of pNETs will require development of staging guidelines with higher predictive value. Inclusion of Ki‐67 labeling >10% as an indicator of aggressive disease may contribute to such improvements. J. Surg. Oncol. 2012; 106:724–727. © 2012 Wiley Periodicals, Inc.
Olfactory identification testing as a predictor of the development of Alzheimer's dementia: A systematic review
Authors: Sun Gordon H. , Raji Cyrus A. , MacEachern Mark P. , Burke James F.
Published: May 2012

Objectives/Hypothesis:

To evaluate the utility of olfactory identification tests as prognostic instruments for Alzheimer's dementia (AD).

Study Design:

Systematic review.

Methods:

In accordance with PRISMA guidelines, PubMed and Ovid MEDLINE, EMBASE, ISI Web of Science, PsycINFO, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched to determine the quality and quantity of longitudinal and cross‐sectional research on this topic.

Results:

Two prospective longitudinal cohort studies and 30 cross‐sectional studies met inclusion criteria. The prospective longitudinal studies evaluated subjects with or without mild cognitive impairment (MCI) while also using olfactory identification testing as part of a neurocognitive evaluation. The first study reported an increased risk of later onset of AD in subjects with baseline hyposmia, whereas the second study suggested a possible relationship between decreased olfaction in participants with MCI and conversion to AD but was inconclusive due to low follow‐up rates. Wide variability in the type of olfactory identification test used and the reporting of results precluded meta‐analysis. The cross‐sectional studies demonstrated a positive association between poorer performance on olfactory identification testing and AD.

Conclusions:

Although there is evidence suggesting an association between decreased olfaction and AD, rigorously designed longitudinal cohort studies are necessary to clarify the value of olfactory identification testing in predicting the onset of AD.
Selective Laser Melting
Authors: Bremen Sebastian , Meiners Wilhelm , Diatlov Andrei
Published: May 2012

Manufacturing enterprises in highwage countries such as Germany are increasingly being exposed to global competition. These enterprises are confronted by an increasing demand for individualized, high quality as well as low‐cost products [1]. Additive manufacturing methods have accelerated their technological capability in the last few years and provide great potential to fulfill these challenges. The most common additive manufacturing method is called Selective Laser Melting (SLM), developed at the Fraunhofer Institute for Laser Technology ILT [2].
Language adaptation and learning: Getting explicit about implicit learning
Authors: Chang Franklin , Janciauskas Marius , Fitz Hartmut
Published: May 2012

Linguistic adaptation is a phenomenon where language representations change in response to linguistic input. Adaptation can occur on multiple linguistic levels such as phonology (tuning of phonotactic constraints), words (repetition priming), and syntax (structural priming). The persistent nature of these adaptations suggests that they may be a form of implicit learning and connectionist models have been developed which instantiate this hypothesis. Research on implicit learning, however, has also produced evidence that explicit chunk knowledge is involved in the performance of these tasks. In this review, we examine how these interacting implicit and explicit processes may change our understanding of language learning and processing.
Typological Universals as Reflections of Biased Learning: Evidence from Artificial Language Learning
Authors: Culbertson Jennifer
Published: May 2012

The study of language typology has played a critical role in revealing potential constraints on possible linguistic systems. Such constraints, often called “typological universals” have long been used to support a foundational premise of generative linguistics—that languages share a set of underlying commonalities. However, recent research has challenged the idea that typological universals—which (at least on the surface) are often statistical tendencies rather than absolute laws—reflect meaningful biases in the linguistic or cognitive system. In part as a response to these critiques, new behavior methods have been developed to probe the link between recurrent typological patterns and the linguistic (and broader cognitive) system. This article focuses on the novel findings which have resulted from this trend, in particular those which use Artificial Language Learning (ALL) paradigms. This exciting strand of research suggests the viability of experimental methods for investigating constraints on human language, and points to new ways of gaining traction on critical questions in cognitive science.
Friction and wear in sliding contact of cast iron against phenolic resin composites reinforced with carbonaceous fibres from plantain fibre bundles
Authors: Betancourt S. , Cruz J. , Toro A.
Published: May 2012

Carbonaceous fibres from Colombian plantain crops residues were obtained by slow pyrolysis process to preserve the morphological aspects of the natural fibres. Composite materials were manufactured by thermal press process using carbonaceous fibres and commercial phenolic resin as reinforcement and matrix, respectively. Different reinforcement contents (0–12.5% v/v) were evaluated in a pin‐on‐disc tribometer to determine the effect on wear and coefficient of friction of this kind of carbonaceous fibres as a potential reinforcement or lubricant filler for tribological applications. Cast iron brake discs were used as counter bodies in all the tests. Worn surfaces of composite pins and metallic discs were analysed in optical and scanning electron microscopes.

A decrease in both friction coefficient and mass loss of composites was observed with the increase in fibre volume fraction. The reduction was associated to a beneficial effect of the detachment of carbonaceous material from the worn surface, which remains at the interface between the composite and the cast iron and acts as a solid lubricant. Although adhesion marks were observed, surface fatigue and polymer crazing were identified as principal wear mechanisms of the composites. Copyright © 2012 John Wiley & Sons, Ltd.
Atorvastatin inhibits pancreatic carcinogenesis and increases survival in LSL‐KrasG12D‐LSL‐Trp53R172H‐Pdx1‐Cre mice
Authors: Liao Jie , Chung Yeon T. , Yang Allison L. , Zhang Meng , Li Haonan , Zhang Wanying , Yan Liang , Yang Guang‐Yu
Published: May 2012

There are several studies supporting the role of HMG‐CoA reductase inhibitors such as atorvastatin against carcinogenesis, in which inhibiting the generation of prenyl intermediates involved in protein prenylation plays the crucial role. Mutation of Kras gene is the most common genetic alteration in pancreatic cancer and the Ras protein requires prenylation for its membrane localization and activity. In the present study, the effectiveness of atorvastatin against pancreatic carcinogenesis and its effect on protein prenylation were determined using the LSL‐KrasG12D‐LSL‐Trp53R172H‐Pdx1‐Cre mouse model (called Pankras/p53 mice). Five‐week‐old Pankras/p53 mice were fed either an AIN93M diet or a diet supplemented with 100 ppm atorvastatin. Kaplan–Meier survival analysis with Log‐Rank test revealed a significant increase in survival in mice fed 100 ppm atorvastatin (171.9 ± 6.2 d) compared to the control mice (144.9 ± 8.4 d, P < 0.05). Histologic and immunohistochemical analysis showed that atorvastatin treatment resulted in a significant reduction in tumor volume and Ki‐67‐labeled cell proliferation. Mechanistic studies on primary pancreatic tumors and the cultured murine pancreatic carcinoma cells revealed that atorvastatin inhibited prenylation in several key proteins, including Kras protein and its activities, and similar effect was observed in pancreatic carcinoma cells treated with farnesyltransferase inhibitor R115777. Microarray assay on the global gene expression profile demonstrated that a total of 132 genes were significantly modulated by atorvastatin; and Waf1p21, cyp51A1, and soluble epoxide hydrolase were crucial atorvastatin‐targeted genes which involve in inflammation and carcinogenesis. This study indicates that atorvastatin has the potential to serve as a chemopreventive agent against pancreatic carcinogenesis. © 2012 Wiley Periodicals, Inc.
Suppression of AMF/PGI‐mediated tumorigenic activities by ursolic acid in cultured hepatoma cells and in a mouse model
Authors: Shih Wen‐Ling , Yu Feng‐Ling , Chang Ching‐Dong , Liao Ming‐Huei , Wu Hung‐Yi , Lin Ping‐Yuan
Published: May 2012

Our previous studies demonstrated that autocrine motility factor/phosphoglucose isomerase (AMF/PGI) possesses tumorigenic activities through the modulation of intracellular signaling. We then investigated the effects of ursolic acid (UA), oleanolic acid (OA), tangeretin, and nobiletin against AMF/PGI‐mediated oncogenesis in cultured stable Huh7 and Hep3B cells expressing wild‐type or mutated AMF/PGI and in a mouse model in this study. The working concentrations of the tested compounds were lower than their IC10, which was determined by Brdu incorporation and colony formation assay. Only UA efficiently suppressed the AMF/PGI‐induced Huh7 cell migration and MMP‐3 secretion. Additionally, UA inhibited the AMF/PGI‐mediated protection against TGF‐β‐induced apoptosis in Hep3B cells, whereas OA, tangeretin, and nobiletin had no effect. In Huh7 cells and tumor tissues, UA disrupted the Src/RhoA/PI 3‐kinase signaling and complex formation induced by AMF/PGI. In the Hep3B system, UA dramatically suppressed AMF/PGI‐induced anti‐apoptotic signaling transmission, including Akt, p85, Bad, and Stat3 phosphorylation. AMF/PGI enhances tumor growth, angiogenesis, and pulmonary metastasis in mice, which is correlated with its enzymatic activity, and critically, UA intraperitoneal injection reduces the tumorigenesis in vivo, enhances apoptosis in tumor tissues and also prolongs mouse survival. Combination of sub‐optimal dose of UA and cisplatin, a synergistic tumor cell‐killing effects was found. Thus, UA modulates intracellular signaling and might serve as a functional natural compound for preventing or alleviating hepatocellular carcinoma. © 2012 Wiley Periodicals, Inc.
Highlights in Antiviral Drug Research: Antivirals at the Horizon
Authors: Clercq Erik De
Published: May 2012

This review highlights ten “hot topics” in current antiviral research: (i) new nucleoside derivatives (i.e., PSI‐352938) showing high potential as a direct antiviral against hepatitis C virus (HCV); (ii) cyclopropavir, which should be further pursued for treatment of human cytomegalovirus (HCMV) infections; (iii) North‐methanocarbathymidine (N‐MCT), with a N‐locked conformation, showing promising activity against both α‐ and γ‐herpesviruses; (iv) CMX001, an orally bioavailable prodrug of cidofovir with broad‐spectrum activity against DNA viruses, including polyoma, adeno, herpes, and pox; (v) favipiravir, which is primarily pursued for the treatment of influenza virus infections, but also inhibits the replication of other RNA viruses, particularly (‐)RNA viruses such as arena, bunya, and hanta; (vi) newly emerging antiarenaviral compounds which should be more effective (and less toxic) than the ubiquitously used ribavirin; (vii) antipicornavirus agents in clinical development (pleconaril, BTA‐798, and V‐073); (viii) natural products receiving increased attention as potential antiviral drugs; (ix) antivirals such as U0126 targeted at specific cellular kinase pathways [i.e., mitogen extracellular kinase (MEK)], showing activity against influenza and other viruses; and (x) two structurally unrelated compounds (i.e., LJ‐001 and dUY11) with broad‐spectrum activity against virtually all enveloped RNA and DNA viruses. © 2012 Wiley Periodicals, Inc. Med. Res. Rev., 00, No. 0, 1–34, 2012
A Novel QSPR Model for Prediction of Gas to Dimethyl Sulfoxide Solvation Enthalpy of Organic Compounds Based on Support Vector Machine
Authors: Golmohammadi Hassan , Dashtbozorgi Zahra , Acree William E.
Published: May 2012

In this study, a quantitative structureproperty relationship (QSPR) study is developed for the prediction of gas to dimethyl sulfoxide solvation enthalpy (ΔHSolv) of organic compounds based on molecular descriptors calculated solely from molecular structure considerations. Diverse types of molecular descriptors were calculated to represent the molecular structures of the various compounds studied. Multiple linear regression (MLR) was employed to select an optimal subset of descriptors that have significant contributions to the ΔHSolv overall property. Our investigation revealed that the dependence of physicochemical properties on solvation enthalpy is a nonlinear observable fact and that MLR method is unable to model the solvation enthalpy accurately. It has been observed that support vector machine (SVM) and artificial neural network (ANN) demonstrates better performance compared with MLR. The standard error value of the test set for SVM is 1.731 kJ mol−1, while it is 2.303 kJ mol−1 and 5.146 kJ mol−1 for ANN and MLR, respectively. The results showed that the calculated ΔHSolv values by SVM were in good agreement with the experimental data, and the performance of the SVM model was superior to those of MLR and ANN ones.
Blast‐induced neurotrauma leads to neurochemical changes and neuronal degeneration in the rat hippocampus
Authors: Sajja Venkata Siva Sai Sujith , Galloway Matthew P. , Ghoddoussi Farhad , Thiruthalinathan Dhananjeyan , Kepsel Andrea , Hay Kathryn , Bir Cynthia A. , VandeVord Pamela J.
Published: May 2012

Blast‐induced neurotrauma is a major concern because of the complex expression of neuropsychiatric disorders after exposure. Disruptions in neuronal function, proximal in time to blast exposure, may eventually contribute to the late emergence of clinical deficits. Using magic angle spinning 1H MRS and a rodent model of blast‐induced neurotrauma, we found acute (24–48 h) decreases in succinate, glutathione, glutamate, phosphorylethanolamine and γ‐aminobutyric acid, no change in N‐acetylaspartate and increased glycerophosphorylcholine, alterations consistent with mitochondrial distress, altered neurochemical transmission and increased membrane turnover. Increased levels of the apoptotic markers Bax and caspase‐3 suggested active cell death, consistent with increased FluoroJade B staining in the hippocampus. Elevated levels of glial fibrillary acidic protein suggested ongoing inflammation without diffuse axonal injury measured by no change in β‐amyloid precursor protein. In conclusion, blast‐induced neurotrauma induces a metabolic cascade associated with neuronal loss in the hippocampus in the acute period following exposure. Copyright © 2012 John Wiley & Sons, Ltd.
High Precision Freeform Polymer Optics
Authors: Dick Lars
Published: May 2012

Injection molding offers a cost efficient method for manufacturing high precision plastic optics for high volume applications. Beside classical optical surfaces like planes, spheres and also aspheres the demand for surfaces without symmetric properties, so called freeform surfaces, continues to rise. To push the surface accuracy for high volume applications for the molded freeform lens, new 3D iteration cycles to compensate systematically residual errors have to be developed. This paper will illustrate a new way for the manufacturing of ultra precision mold tool inserts with submicron precision and show the manufacturing of replicated freeform surfaces with micrometer range shape accuracy at diameters up to 40 mm. Furthermore, two examples for molded, energy and material efficient freeform optics adapted to the green photonics philosophy are shown and explained.
gSTED Microscopy with an OPSL: Cutting Edge Super‐Resolution
Authors: Eggeling Christian , Honigmann Alf , Schulze Matthias
Published: May 2012

In order to probe cell biology at the molecular level and correlate single molecule activity with macroscopic cellular behavior in real‐time, biologists need farfield microscopy techniques with the highest possible spatial as well as temporal resolution. Driven by this need, the use of lasers in confocal microscopy has taken fluorescence microscopy to the diffraction limit, which was long considered the theoretical and practical limit on spatial resolution of this technique. In the 1990's novel super‐resolution far‐field microscopy (or nanoscopy) approaches based on the reversible modulation of the fluorescence signal have evolved which pushed the spatial resolution to the nanoscale [1]. And Stimulated Emission Depletion (STED) nanoscopy has been developed [2] as a broadly applicable method and can be used with both fixed and live tissue samples [1]. The combination of a continuous‐wave (CW) laser [3] with a gated detection (gSTED) [4] and the availability of a yellow (577 nm) low‐noise laser has enabled further optimization.
Ion Beam Figuring Technology in Optics Manufacturing
Authors: Zeuner Michael , Kiontke Sven
Published: May 2012

Ion beam technologies have become an established alternative to common mechanical polishing methods in manufacturing optics. Ion Beam Figuring (IBF) is increasingly being used for the precise figuring and finishing of optical elements, such as spheres, aspheres and free forms on lenses and mirrors. Next to the finishing of optical components, an IBF process can also be employed on the molds that are used to produce optical lenses. The mold pins that are employed in the consumer goods market usually require a fairly high financial investment. As the quality of a lens ultimately depends on the surface of the optical mold, an error correction process on the mold itself may proof a more cost effective exercise than the polishing of the lenses post‐production.
Leukämie
Authors: Marschalek Rolf , Zündorf Ilse , Dingermann Theo
Published: May 2012

Obwohl der erste Krankheitsfall bereits 1827 beschrieben wurde, dauerte es bis 1845, dass Rudolf Virchow den Begriff “Leukämie” einführte. Zeitgleich beschrieben der Schotte John Hughes Bennett und der Franzose Alfred Donné ebenfalls das Krankheitsbild einer chronischen myeloischen Leukämie (CML).
Genetische Grundlagen von Leukämie‐Erkrankungen
Authors: Marschalek Rolf
Published: May 2012

Zusammenfassend lässt sich resümieren, dass viele pädiatrische Leukämie‐Erkrankungen durch bestimmte chromosomale Translokationen klassifizierbar sind. Zudem finden sich kaum weitere Mutationen (Sekundärmutationen). Dies wird auch durch Studien an ganzen Krebsgenomen bestätigt. Das lässt den Schluss zu, dass chromosomale Translokationen gravierende Folgen für betroffene Zellen haben, die Wachstum, Apoptose und Stammzelleigenschaften beeinflussen. Die entstehenden Fusionsgene kodieren für onkogene Fusionsproteine, die Zellen in Tumorzellen verwandeln können. Damit unterscheiden sich diese pädiatrischen Tumoren in genetischer Hinsicht deutlich von anderen soliden Tumoren, wie z.B. Brustkrebs oder Dickdarmkrebs bei Erwachsenen, die zwischen 60 und 80 Einzelmutationen pro Patient aufweisen.
Behandlung von Kindern und Jugendlichen mit Rezidiv einer ALL
Authors: Tallen Gesche , Henze Günter , von Stackelberg Arend
Published: May 2012

Leukämien sind mit einem Anteil von etwa 30 % die häufigsten bösartigen Erkrankungen bei Kindern und Jugendlichen. Noch in den 1960er Jahren kam die Botschaft “Ihr Kind hat eine Leukämie” einem Todesurteil gleich, denn zu dieser Zeit galten Leukämien bei Kindern und Jugendlichen noch als unheilbar. Heute überleben in den westlichen Industrieländern etwa vier von fünf Kindern mit einer akuten lymphoblastischen Leukämie (ALL). Und das fünfte? – Leider gehört zu den jungen Menschen, die auch heute noch an der Erkrankung versterben, die Mehrzahl der Rezidivpatienten.
Infektiöse Komplikationen bei akuter lymphatischer Leukämie
Authors: Lehrnbecher Thomas
Published: May 2012

Mit immer intensiveren Therapien versucht man die Heilungsrate bei Kindern mit Leukämien zu verbessern. Durch die Therapie‐Intensivierung wird jedoch gleichzeitig auch eine zunehmende Immunsuppression hervorgerufen, sodass infektiöse Komplikationen trotz Verbesserungen in der Supportivtherapie noch immer eine wichtige Ursache für Morbidität und Mortalität bei Kindern mit akuter lymphatischer Leukämie (ALL) darstellen.
A case study of a child with chronic hemolytic anemia due to a Donath–Landsteiner positive, IgM anti‐I autoantibody
Authors: Karafin Matthew S. , Shirey R. Sue , Ness Paul M. , King Karen E. , Keefer Jeffrey
Published: May 2012

In children, paroxysmal cold hemoglobinuria (PCH) is generally considered an acute self‐limited autoimmune hemolytic anemia caused by an IgG biphasic auto‐anti‐P antibody identified by the Donath–Landsteiner (D‐L) test. We report a case of a 5‐year‐old female with a chronic hemolytic anemia. The etiology of the hemolysis appears to be an unusual D‐L positive, IgM antibody with specificity for the I antigen. The clinical course is described and a discussion of PCH and the D‐L antibody is presented. We also discuss intravenous immunoglobulin infusions as a therapy for children with this form of severe chronic autoimmune hemolytic anemia. Pediatr Blood Cancer 2012; 59: 953–955. © 2012 Wiley Periodicals, Inc.
Synthesis, characterization of poly‐2‐ (2‐hydroxybenzylideneamino)‐6‐phenyl‐4,5,6, 7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile: Investigation of antibacterial activity and optical properties
Authors: Kaya Esin , Turan Nevin , Gündüz Bayram , Çolak Naki , Körkoca Hanifi
Published: May 2012

The oxidative polycondensation reaction conditions of 2‐(2‐hydroxybenzylideneamino)‐6‐phenyl‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile were examined. The magnitude of the reflectance of the polymer decreases sharply with increasing of wavelength up to 524 nm, then reflectance of the polymer increases slowly with increasing of wavelength. The refractive index values of the polymer vary from 1.474 to 2.350. The Ep and Ed values of the polymer were found to be 4.56 and 7.068 eV, respectively. Absorption coefficient K of the polymer is of the order 817.062–1434.77 m−1. Angle values of incidence and refraction of the polymer vary from 57.36 to 66.95° and from 23.05 to 32.65°, respectively. The film‐phase thickness of the polymer increases with increasing photon energy. The thickness, d, of the polymer was of the order 439.3–4184.7 Å for 190 and 1100 nm, respectively. The real part of dielectric constant of the polymer decreases slowly with increasing of frequency up to about 600 THz, then the real part of dielectric constant of the polymer increases sharply with increasing of frequency. The real and imaginary parts of dielectric constant of the polymer vary from 2.17 to 5.52 and from 5.81 × 10−5 to 3.58 × 10−4, respectively. Finally, polymer was tested for antibacterial activities against some bacteria. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Viscoelastic behaviors of shell‐crosslinked core–shell nanoparticles suspended in polystyrene solutions
Authors: Yin Xianze , Tan Yeqiang , Chen Yuyin , Song Yihu , Zheng Qiang
Published: May 2012

Shell‐crosslinked core–shell nanoparticles (SCCSNs) were prepared via miniemulsion polymerization of styrene in the presence of silane‐modified inorganic silica. The polystyrene (PS) shell of 58.6% in weight fraction was crosslinked using divinylbenzene. SCCSNs were spherical with a diameter distribution from 32 to 98 nm determined by dynamic light scattering. Dynamic rheology of SCCSNs suspended in PS/toluene solution was compared with that of suspensions of naked silica. The critical strain for onset of rheological nonlinearity was independent of SCCSN concentration above a concentration threshold, which differs from the silica suspensions. Linear dynamic rheological investigation revealed that SCCSN suspensions with a PS volume fraction of 20% were fluid‐like at low particle concentrations while suspensions containing 4.2 vol% SCCSNs formed a gel‐like structure. On the contrary, the silica suspensions with 20.0 vol% PS underwent a fluid‐to‐solid‐like transition with increasing silica concentration. Reasons for the different rheological behaviors of the naked silica and SCCSN suspensions are discussed. Copyright © 2012 Society of Chemical Industry
Was leistet die Erde?
Authors: Kleidon Axel
Published: May 2012

Die Erde als thermodynamisches System betrachtet arbeitet als planetare Wärmekraftmaschine. Sie erzeugt Leistung, verrichtet Arbeit und erhält damit die Dynamik. Die Grenzen beschreibt die Thermodynamik, insbesondere der zweite Hauptsatz, der die Umsetzung von Wärme zu Leistung limitiert. Diese Betrachtungsweise erschließt eine grundsätzliche Perspektive über die Zusammenhänge und Wechselwirkungen von planetaren Antrieben und Erdsystemprozessen. Sie macht deutlich, wie die physikalische Leistung im Erdsystem limitiert ist. Zudem zeigt sie, welche zentrale Bedeutung das Leben auf der Erde für die Erzeugung von chemischer freier Energie hat. Allerdings verbraucht die menschliche Aktivität bereits auf planetarer Skala erheblich an freier Energie. Eine nachhaltige Planung der Zukunft sollte darauf zielen, durch effizientere Nutzung der Solarstrahlung die Gesamtleistung des Erdsystems zu erhöhen.
Mond, Erde und Sonne als Antrieb
Authors: Ruprecht Albert , Weilepp Jochen
Published: May 2012

Für den Klimaschutz und eine nachhaltige Energieversorgung erfährt die Nutzung der Meeresströmungen zunehmendes Interesse. Bis heute wurden eine große Anzahl an Konzepten und Technologien entwickelt und an einigen Pilotanlagen auch erste Erfahrungen gesammelt. Es zeigt sich, dass die raue, technikfeindliche Umgebung des Meeres eine große Herausforderung darstellt und besondere Entwicklungen erfordert. Am Beispiel der Technologieentwicklung von Voith Hydro werden die notwendigen Anstrengungen erläutert, die einen langjährigen, zuverlässigen Betrieb gewährleisten.
Ultraschnelle Bewegungen im magnetischen Phasenübergang
Authors: Staub Urs , Johnson Steven L.
Published: May 2012

Das Wissen, wie die Ausrichtung magnetischer Momente (Spins) in ultrakurzen Zeitspannen geändert werden kann, ist von großem Interesse in der modernen Datenspeicherung. Mit welcher Geschwindigkeit sich die Spins neu ausrichten, nachdem sie angeregt wurden, ist bis heute jedoch fast völlig unbekannt. Experimente mit dem ersten harten Röntgen‐Freie‐Elektronen‐Laser, der Linear Coherent Light Source am Stanford National Accelerator Laboratory SLAC (USA), brachten jetzt Einblicke in das ultraschnelle Verhalten magnetischer Phasenübergänge.
Quantenoptik mit Röntgenlicht: Eisen wird transparent
Authors: Röhlsberger Ralf
Published: May 2012

Mit Hilfe von intensivem Laserlicht lassen sich bestimmte Materialien für Licht einer bestimmten Wellenlänge durchsichtig machen. Dieser Effekt der elektromagnetisch induzierten Transparenz spielt eine große Rolle auf dem Weg zu optischen Quantencomputern, da man auf diese Weise Licht mit Licht steuern kann. An der Synchrotronstrahlungsquelle PETRA III am DESY in Hamburg demonstrierte unsere Forschergruppe erstmals elektromagnetisch induzierte Transparenz mit Röntgenlicht.
Pionier im Silicon Valley
Authors: Loos Andreas
Published: May 2012

Geboren wird er in London als Sohn eines amerikanischen Bergbauingenieurs. Als er drei Jahre alt ist, kehrt die Familie in die USA zurück. Doch die Eltern halten wenig von den dortigen öffentlichen Schulen, und daher übernimmt Mommy selbst für ein paar Jahre den Mathe‐ und Leseunterricht. Jahre später promoviert er am Massachusetts Institute of Technology über die “Berechnung von Elektronenwellenfunktionen in Natrium‐Chlorid‐Kristallen.” Die Festkörperphysik wird ihn Zeit seines Lebens nicht mehr loslassen.
The influence of admission characteristics on outcome: Evidence from a medium secure forensic cohort
Authors: Gibbon Simon , Huband Nick , Bujkiewicz Sylwia , Hollin Clive R. , Clarke Martin , Davies Steffan , Duggan Conor
Published: May 2012

Objective

Outcomes for any mental health service will vary with the characteristics of those admitted as well as with the clinical provision of the service itself. This study aims to explore, for a medium secure forensic service in England, temporal changes in (1) characteristics of those admitted and (2) outcome after discharge and (3) to examine whether such changes are related.

Method

Baseline characteristics and reconviction outcomes were derived from multiple data sources for 550 first admissions to a medium secure forensic unit for a 20‐year period. Time to reconviction was examined using Kaplan–Meier analysis and Cox regression.

Results

Over time, severity of admissions increased, as did discharges to prison; discharges to non‐secure hospitals reduced. Risk of reconviction increased by 3.9%–4.2% for each year of admission from 1983, which was explained by the increased admission of higher‐risk patients.

Conclusion

This medium secure service admitted patients with increasing levels of risk; reoffending rates reflect admission characteristics. Service funding decisions should take account of the characteristics of those admitted.

Significant outcomes

This study indicates that the profile of patients admitted over a 20‐year period increased in severity.

Over time, reconviction after discharge occurred earlier after release.

This increase in reconviction was explained by the type of patient admitted.

Limitations

Examination of a cohort from a single medium secure unit limits the generalizability of the findings.

The study focuses on a criminological outcome measure (i.e. reconviction); other domains may be equally relevant (e.g. the relief of psychological distress).

Examining an entire series of admissions introduces heterogeneity by, for example, considering the outcome of men and women together. Copyright © 2012 John Wiley & Sons, Ltd.
Counteracting Free-Riding with Team Morale—An Experimental Study
Authors: He Jun
Published: May 2012

This study focuses on a behavioral perspective to examine the detrimental effects of free-riding on team performance, and investigates team morale as a key factor that counteracts the tendency of free-riding among team members. Results of the empirical test imply that enhancing team morale can effectively reduce the scale of free-riding behavior in project teams; in addition, controlling team size also provides help to constrain the undesired behavior. The two means can be carefully applied to project management during early stages of project development before the commitment of significant resources. Implications for both research and team practices are discussed.
Impaired mental health among the bereaved spouses of cancer patients
Authors: Asai Mariko , Akizuki Nobuya , Fujimori Maiko , Shimizu Ken , Ogawa Asao , Matsui Yutaka , Akechi Tatsuo , Itoh Kuniaki , Ikeda Masafumi , Hayashi Ryuichi , Kinoshita Taira , Ohtsu Atsushi , Nagai Kanji , Kinoshita Hiroya , Uchitomi Yosuke
Published: May 2012

Objective

Few cancer physicians routinely provide bereavement follow‐up in clinical practice. The purpose of this study was to identify the prevalence of impaired mental health among the bereaved spouses over several years and explore the indicators for early detection of high‐risk spouses during end‐of life (EOL) care.

Methods

A cross‐sectional mail survey was conducted for the bereaved spouses of patients who had died at the National Cancer Center Hospital of Japan. Bereaved spouses with potential psychiatric disorders were identified by the cut‐off score of the 28‐item General Health Questionnaire. Associated factors of potential psychiatric disorders were explored by logistic regression analysis.

Results

A total of 821 spouses experiencing bereavement from 7 months to 7 years returned the questionnaires. Overall mean prevalence of potential psychiatric disorders was 44% (360/821). Bereaved spouses ‘under 55 years’ (71%) or ‘2 years after bereavement’ (59%) revealed a significantly higher prevalence (p < 0.01). Associated factors during EOL care were several characteristics such as ‘spouses’ history of psychiatric disorder (odds ratio (OR) = 3.19), ‘patients’ with stomach cancer (OR = 1.87), and ‘patients’ using psychiatric consultation services (OR = 1.52) as well as spouses’ dissatisfaction with EOL care such as ‘physicians’ treatment of physical symptoms’ (OR = 3.44) and ‘time spent communicating with patients’ (OR = 1.55).

Conclusions

Nearly half the bereaved spouses showed potential psychiatric disorders even 7 years after bereavement. Patients' psychological distress, spouses' history of psychiatric disorder, and dissatisfaction with EOL care were indicators of high‐risk spouses. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of a supervised, outpatient exercise and physiotherapy programme in children with cystic fibrosis
Authors: Urquhart Donald , Sell Zoe , Dhouieb Elaine , Bell Gillian , Oliver Sarah , Black Ryan , Tallis Matthew
Published: May 2012

Previous work suggests benefit from outpatient exercise and physiotherapy in children with cystic fibrosis (CF), namely improved exercise capacity and lung function measures, as well reduced intravenous (IV) antibiotic needs. Our study aim was to investigate the effect of a year‐long supervised outpatient exercise and physiotherapy programme in children with CF. Subjects with CF aged ≥10 years who had received ≥4 courses of IV antibiotics in 2009 were enrolled and seen fortnightly for supervised exercise and physiotherapy throughout 2010. In addition, they were expected to exercise three times weekly, and if unwell complete additional physiotherapy sessions extra to usual chest physiotherapy. Assessments of exercise capacity using the Modified Shuttle Test (MST) and quality of life (QOL; CFQ‐UK) were recorded at baseline and after 1 year. Regular spirometry was performed before and throughout the study. Data were collected on IV antibiotic days. 12 subjects (6 female) were enrolled with mean (95% CI) age of 13.3 (11.8–14.6) years at study entry. A significant reduction in IV antibiotic days from 60 (56–64) days in 2009 to 50 (44–56) in 2010 (P = 0.02) was noted, along with improved MST distance (m) [735 (603–867) vs. 943 (725–1,161), P = 0.04] and level attained [9.4 (8.4–10.5) vs. 11.1 (9.6–12.6), P = 0.04]. Significant improvements in CFQ‐UK scores for physical [59 (47–72) vs. 83 (74–92), P = 0.001], emotional [63 (55–72) vs. 84 (74–93), P < 0.001], treatment [41 (30–51) vs. 61 (48–73), P = 0.002], and respiratory [54 (42–66) vs. 76 (70–82), P = 0.002] domains were noted. The mean (95% CI) rate of change of FEV1 was −4 (−18, +10)% in 2009, but was +6 (−2, +13)% in 2010, although this did not reach statistical significance. Supervised, outpatient exercise and physiotherapy are associated with improvements in QOL and exercise tolerance, a reduction in IV antibiotic days, and a trend towards reducing lung function decline in children with CF. The cost of IV antibiotics was reduced by £66,384 ($104,000) in 2010 when compared with 2009. Such cost‐benefit may have implications for workforce planning and service provision. Pediatr Pulmonol. 2012; 47:1235–1241. © 2012 Wiley Periodicals, Inc.
Nasopharyngeal oxygen with intermittent nose‐close and abdomen‐compression: A novel resuscitation technique in a piglet model
Authors: Soong Wen‐Jue , Jeng Mei‐Jy , Lee Yu‐Sheng , Tsao Pei‐Chen , Soong Yen‐Hui Matthew
Published: May 2012

Objective: To evaluate the efficacy of a simple and novel cardiopulmonary resuscitation (CPR) technique, nasopharyngeal oxygen with intermittent nose‐close and abdomen‐compression (NPO2‐NC‐AC) in an animal model. Design: Prospective piglet study. Setting: In an animal physiology laboratory of a medical university. Piglets: Six healthy piglets <14 days old. Interventions: Spontaneous breathing of the anesthetized piglets (n = 6) was medically ceased until severe bradycardia (<20 beat/min). NPO2‐NC‐AC CPR trial was then initiated by delivering NPO2 at 1.0–1.5 L/kg/min and intermittently performing the NC‐AC maneuver: (1) NC for inspiration, occluded nostrils for 1 sec; and (2) AC for expiration, released nostrils, and compressed the abdomen for 1 sec. NC‐AC was repeated at a rate of 30/min for 5 min. This CPR trial was repeated three times in each piglet. Cardiopulmonary variables were monitored, recorded, and compared. Measurements and Main Results: A total of 18 CPR trials were performed. All of these acute life‐threatening asphyxia events rapidly improved within 1 min of CPR. Cardiopulmonary variables recovered to the baseline levels and oxygenation continually increased. The intratracheal pressure (Ptr) values of positive end expiratory pressure and peak inspiratory pressure values were 4.3 ± 0.8 cmH2O and 26.2 ± 4.1 cmH2O, respectively. Chest wall movement was observed when the Ptr reached 17.5 ± 3.1 cmH2O. All six piglets fully recovered after 63.8 ± 7.2 min of experiment without additional support. Conclusions: NPO2‐NC‐AC is a simple and effective CPR technique for severe acute cardiopulmonary asphyxia in piglets. It may be clinically applicable for supportive or rescue use. Pediatr Pulmonol. 2013; 48:288–294. © 2012 Wiley Periodicals, Inc.
Transient interactions of a slow‐folding protein with the Hsp70 chaperone machinery
Authors: Sekhar Ashok , Santiago Margarita , Lam Hon Nam , Lee Jung Ho , Cavagnero Silvia
Published: May 2012

Most known proteins have at least one local Hsp70 chaperone binding site. Does this mean that all proteins interact with Hsp70 as they fold? This study makes an initial step to address the above question by examining the interaction of the E.coli Hsp70 chaperone (known as DnaK) and its co‐chaperones DnaJ and GrpE with a slow‐folding E.coli substrate, RNase HD. Importantly, this protein is a nonobligatory client, and it is able to fold in vitro even in the absence of chaperones. We employ stopped‐flow mixing, chromatography, and activity assays to analyze the kinetic perturbations induced by DnaK/DnaJ/GrpE (K/J/E) on the folding of RNase HD. We find that K/J/E slows down RNase HD's apparent folding, consistent with the presence of transient chaperone‐substrate interactions. However, kinetic retardation is moderate for this slow‐folding client and it is expected to be even smaller for faster‐folding substrates. Given that the interaction of folding‐competent substrates such as RNase HD with the K/J/E chaperones is relatively short‐lived, it does not significantly interfere with the timely production of folded biologically active substrate. The above mode of action is important because it preserves K/J/E bioavailability, enabling this chaperone system to act primarily by assisting the folding of other misfolded and (or) aggregation‐prone cellular proteins that are unable to fold independently. When refolding is carried out in the presence of K/J and absence of the nucleotide exchange factor GrpE, some of the substrate population becomes trapped as a chaperone‐bound partially unfolded state.
Genetic polymorphism and prostate cancer aggressiveness: A case‐only study of 1,536 GWAS and candidate SNPs in African‐Americans and European‐Americans
Authors: Bensen Jeannette T. , Xu Zongli , Smith Gary J. , Mohler James L. , Fontham Elizabeth T.H. , Taylor Jack A.
Published: May 2012

BACKGROUND

Genome‐wide association studies have established a number of replicated single nucleotide polymorphisms (SNPs) for susceptibility to prostate cancer (CaP), but it is unclear whether these susceptibility SNPs are also associated with disease aggressiveness. This study evaluates whether such replication SNPs or other candidate SNPs are associated with CaP aggressiveness in African‐American (AA) and European‐American (EA) men.

METHODS

A 1,536 SNP panel which included 34 genome‐wide association study (GWAS) replication SNPs, 38 flanking SNPs, a set of ancestry informative markers, and SNPs in candidate genes and other areas was genotyped in 1,060 AA and 1,087 EA men with incident CaP from the North Carolina‐Louisiana Prostate Cancer Project (PCaP). Tests for association were conducted using ordinal logistic regression with a log‐additive genotype model and a 3‐category CaP aggressiveness variable.

RESULTS

Four GWAS replication SNPs (rs2660753, rs13254738, rs10090154, rs2735839) and seven flanking SNPs were associated with CaP aggressiveness (P < 0.05) in three genomic regions: One at 3p12 (EA), seven at 8q24 (5 AA, 2 EA), and three at 19q13 at the kallilkrein‐related peptidase 3 (KLK3) locus (two AA, one AA and EA). The KLK3 SNPs also were associated with serum prostate‐specific antigen (PSA) levels in AA (P < 0.001) but not in EA. A number of the other SNPs showed some evidence of association but none met study‐wide significance levels after adjusting for multiple comparisons.

CONCLUSIONS

Some replicated GWAS susceptibility SNPs may play a role in CaP aggressiveness. However, like susceptibility, these associations are not consistent between racial groups. Prostate 73: 11–22, 2013. © 2012 Wiley Periodicals, Inc.
The crystal structure of dihydrodipicolinate synthase from Escherichia coli with bound pyruvate and succinic acid semialdehyde: Unambiguous resolution of the stereochemistry of the condensation product
Authors: Boughton Berin A. , Dobson Renwick C. J. , Hutton Craig A.
Published: May 2012

The crystal structure of Escherichia coli dihydrodipicolinate synthase with pyruvate and substrate analogue succinic acid semialdehyde condensed with the active site lysine‐161 was solved to a resolution of 2.3 Å. Comparative analysis to a previously reported structure both resolves the configuration at the aldol addition center, where the final addition product clearly displays the (S)‐configuration, and the final conformation of the adduct within the active site. Direct comparison to two other crystal structures found in the Protein Data Bank, 1YXC, and 3DU0, demonstrates significant similarity between the active site residues of these structures. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Electrical characterization of 4H‐SiC Schottky diodes with RuWOx Schottky contacts before and after irradiation by fast electrons
Authors: Benkovska Jana , Stuchlikova Lubica , Buc Dalibor , Čaplovic Lubomir
Published: May 2012

The impact of radiation damage on the device performance of 4H‐SiC Schottky barrier diodes (SBDs) with RuWOx Schottky contacts, which were irradiated at room temperature with 9 MeV electrons (absorbed dose of 50 Gy), is studied by current–voltage (I–V) and capacitance–voltage (C–V) methods measured in the temperature range of 85–400 K. We have observed the radiation‐induced decrease of the Schottky barrier height (SBH) from original Φb = 1.13–1.06 eV, increase of the ideality factor from n = 1.14 to 1.39 and the noticeable increase of the saturation current from IS = 7.29 to 77.31 pA and the series resistance from RS = 2.9 to 7.9 Ω calculated from I–V measurements at T = 300 K. As a result of electron irradiation deep energy levels originated in the structure and caused the increase of serial resistance and leakage current. The DLTS results have shown several deep energy levels, e.g., EC – 0.637 eV pointing to radiation‐induced Z1/2 structural defects in SiC. No degradation is observed from the measured C–V curves. The experimental value of the effective Richardson constant A* = 50.68 A/cm2/K2 for the irradiated sample was calculated from the modified Richardson plot.
Formation of aluminum tris (8‐hydroxyquinoline) solution in methanol and fabrication of thin films by ultrasonic spray‐assisted vapor deposition
Authors: Piao Jinchun , Katori Shigetaka , Ikenoue Takumi , Fujita Shizuo
Published: May 2012

Small molecular material, aluminum tris (8‐hydroxyquinoline) (AlQ3), was found to be soluble in methanol under application of high ultrasonic power, and this has opened safe and environmental‐friendly solution‐based deposition of thin films. The chemical state of AlQ3 was analyzed by nuclear magnetic resonance study and the results showed there was no severe damage on AlQ3 atoms applied by high ultrasonic power. The AlQ3 films were fabricated by ultrasonic‐assisted mist deposition method on indium‐tin‐oxide. The low leakage current suggested well‐defined AlQ3 thin films without significant electrical defects such as pinholes.
Unusual behaviour of wave propagation in auxetic structures: P‐waves on free surface and S‐waves in chiral lattices with piezoelectrics
Authors: Malischewsky Peter G. , Lorato Andrea , Scarpa Fabrizio , Ruzzene Massimo
Published: May 2012

We examine some unusual wave propagation characteristics related to auxetic systems represented by continuum isotropic materials and hexagonal chiral lattices with and without active piezoelectric actuation. We show for the first time a peculiar singularity in the ratio between reflected P and S waves in Rayleigh‐wave type propagation for auxetic isotropic materials, which has been otherwise observed only in at least bi‐phase material systems. The other unusual phenomenon is a strong increase of the pass‐stop band frequencies in hexachiral lattices with piezoelectric materials, with no change of the shear‐wave type otherwise occurring in pristine lattice with no piezoelectric contribution.
Magnetic properties of Ni3B2O6 and Co3B2O6 single crystals
Authors: Bezmaternykh L. N. , Sofronova S. N. , Volkov N. V. , Eremin E. V. , Bayukov O. A. , Nazarenko I. I. , Velikanov D. A.
Published: May 2012

Orthorhombic Me3B2O6 (Me = Co, Ni) single crystals of the kotoite family are grown from the fluxes based on a mixture of bismuth trimolybdate and sodium oxide upon spontaneous nucleation. The field and temperature dependences of magnetization of the single crystals with the magnetic field oriented along the principal crystallographic directions are obtained. Unlike Ni3B2O6, Co3B2O6 exhibits strong anisotropy of the magnetic properties. At the temperature T = 10 K, the magnetization curves of Co3B2O6 reveal an anomaly attributed to the spin‐reorientation transition. Strong anisotropy of the magnetic properties of Co3B2O6 is also confirmed by the calculation of the exchange interactions within a simple indirect coupling model.
Effects of purification on the diameter separation of metallic single‐walled carbon nanotubes by gel column chromatography
Authors: Zhang Jing , Tan Furui , Li Hongbo , Jin Hehua , Li Qingwen
Published: May 2012

Metallic single‐walled carbon nanotubes (m‐SWCNTs) with excellent conductivity and transparency are considered to be eminent electrode materials. However, it still remains a challenge to separate m‐SWCNTs by their diameters. As reported in this Letter, by effective purification treatment of SWCNTs, we succeeded in achieving diameter separation of m‐SWCNTs using gel column chromatography. TEM and Raman characterizations revealed that metal catalysts and amorphous carbon on tube surfaces were largely reduced, which contributed to the diameter separation of m‐SWCNTs.

magnified image

The separation process of m‐SWCNTs by gel column chromatography and their corresponding optical absorption spectra.

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