bluuebunny/crossref_metadata_2025 huggingface dataset:
Can organizational climate be managed? Making emotions rational
Authors: Håkonsson Dorthe Døjbak , Obel Børge , Burton Richard M.
Published: February 2008

A leader's job is often to attempt achieving organizational alignment. Many theories propose climate as an effective means to help leaders carry out this task. Nevertheless, our understanding of which exact actions are needed to manage climate remains somewhat diffuse. We present a new cognitiveoriented view on climate, which enables us to discuss the influence of climate on managing the balance between integration and adaptation. In this article, we argue that climate is not as easy to manage as previously argued. In the short run, climate may serve as an effective emotional inertia to maintain the system in fit, as long as it is properly perceived and supported by the leadership style. In the longer run, climate is more influential to change, making it difficult to perceive it properly. This challenge may lead to transformative changes, causing leaders to have little control.
Do all institutions benefit from leadership training? Challenging tradition through systems inquiry
Authors: Nadim Abbas , Singh Parbudyal
Published: February 2008

There is a fascination in the business community with leadership. There is an endless stream of training and development programs on how to become effective leaders to the extent that leadership training is now a big business. But the fascination is not restricted to the business community. People are enthralled by the idea of leadership, search for more information on it, and truly believe that by becoming a leader, they can reach a more desirable future. The purpose of this article is to demonstrate that all organizations do not benefit universally from their investment in employees' leadership training. After reviewing the leadership literature and systems concepts, it is recommended that the redesign of an organization in a social systemic framework will lead to optimization of benefit from leadership training.
Non–contrast‐enhanced MR angiography of the thoracic aorta using cardiac and navigator‐gated magnetization‐prepared three‐dimensional steady‐state free precession
Authors: Amano Yasuo , Takahama Katsuya , Kumita Shinichiro
Published: February 2008

Purpose

To assess the usefulness of non–contrast‐enhanced MR angiography using cardiac and navigator‐gated magnetization‐prepared three‐dimensional (3D) steady‐state free precession (SSFP) imaging for the diagnosis of diseases of the thoracic aorta.

Materials and Methods

Twenty‐two patients with diseases of the thoracic aorta were examined using a 1.5 Tesla unit. Non–contrast‐enhanced MR angiography was done using parasagittal 3D SSFP combined with cardiac‐gating and k‐space weighted navigator‐gating techniques, using T2‐prepared and fat‐suppression pulses. Imaging quality and the diagnostic capability of this technique were compared with the imaging quality of 2D SSFP or contrast‐enhanced 3D MR angiography and with final diagnoses.

Results

Non–contrast‐enhanced 3D MR angiography provided signal‐to‐noise and contrast‐to‐noise ratios of the thoracic aorta comparable to non–contrast‐enhanced 2D or contrast‐enhanced 3D MR angiography (P > 0.17). This imaging technique gave accurate diagnoses in 19 of the 22 patients.

Conclusion

Non–contrast‐enhanced MR angiography using cardiac and navigator‐gated magnetization‐prepared 3D SSFP technique was useful for the diagnosis of diseases of the thoracic aorta. J. Magn. Reson. Imaging 2008. © 2008 Wiley‐Liss, Inc.
Apoptotic insults to human chondrocytes induced by sodium nitroprusside are involved in sequential events, including cytoskeletal remodeling, phosphorylation of mitogen‐activated protein kinase kinase kinase‐1/c‐Jun N‐terminal kinase, and Bax‐Mitochondria‐Mediated caspase activation
Authors: Cherng Yih‐Giun , Chang Hua‐Chia , Lin Yi‐Ling , Kuo Ming‐Liang , Chiu Wen‐Ta , Chen Ruei‐Ming
Published: February 2008

Nitric oxide (NO) can regulate chondrocyte activities. This study was aimed to evaluate the molecular mechanisms of NO donor sodium nitroprusside (SNP)‐induced insults to human chondrocytes. Exposure of human chondrocytes to SNP increased cellular NO levels but decreased cell viability in concentration‐ and time‐dependent manners. SNP time dependently induced DNA fragmentation and cell apoptosis. Treatment with 2‐phenyl‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl 3‐oxide, an NO scavenger, significantly lowered SNP‐induced cell injuries. Administration of SNP interrupted F‐actin and microtubule cytoskeletons and stimulated phosphorylation of mitogen‐activated protein kinase kinase kinase‐1 (MEKK1) and c‐Jun N‐terminal kinase (JNK). Similar to SNP, cytochalasin D, an inhibitor of F‐actin formation, disturbed F‐actin polymerization and increased MEKK1 and JNK activations. Overexpression of a dominant negative mutant of MEKK1 (dnMEK1) in human chondrocytes significantly ameliorated SNP‐induced cell apoptosis. Exposure to SNP promoted Bax translocation from the cytoplasm to mitochondria, but application of dnMEKK1 lowered the translocation. SNP time dependently decreased the mitochondrial membrane potential, complex I NADH dehydrogenase activity, and cellular ATP levels, but increased the release of cytochrome c from mitochondria to the cytoplasm. Activities of caspase‐9, ‐3, and ‐6 were sequentially increased by SNP administration. This study shows that SNP can induce apoptosis of human chondrocytes through sequential events, including cytoskeletal remodeling, activation of MEKK1/JNK, Bax translocation, mitochondrial dysfunction, cytochrome c release, caspase activation, and DNA fragmentation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1018–1026, 2008
Chromatographic separation of cytidine triphosphate from fermentation broth of yeast using anion‐exchange cryogel
Authors: Wang Lianghua , Shen Shaochuan , Yun Junxian , Yao Kejian , Yao Shan‐Jing
Published: February 2008

A novel separation method was developed to isolate directly cytidine triphosphate (CTP) from fermentation broth of yeast using anion‐exchange supermacroporous cryogel. The anion‐exchange cryogel with tertiary amine groups was prepared by graft polymerization. The breakthrough characteristics and elution performance of pure CTP in the cryogel bed were investigated experimentally and the CTP binding capacity was determined. Then the separation experiments of CTP from crude fermentation broth of yeast using the cryogel column were carried out using deionized water and 0.01 M HCl as washing buffer, respectively. The chromatographic behavior was monitored and analyzed. The purity and concentration of the obtained CTP in these processes were determined quantitatively by HPLC. The maximal purity of CTP obtained at the condition of 0.01 M HCl as washing buffer and 0.5 M NaCl in 0.01 M HCl as elution buffer reached 93%.
Investigation of the retention mechanism of naphthol and benzenediol on calix[4]arene stationary phase based on quantum chemistry calculations
Authors: Hu Kai , Qu Kang , Li Yongbo , Ding Chenghua , Wang Xie , Zhang Junqiang , Ye Baoxian , Zhang Shusheng
Published: February 2008

Calixarenes are macrocyclic oligomers having the shape of a conical vase. Their inner cavity can accommodate various guest molecules, i. e. form supramolecules. Thus, calixarenes can be employed to manipulate selectivity in separation sciences. The essential step of separation is the interaction between calixarene and analytes. Therefore, in the present work, the retention mechanisms of benzenediol and naphthol positional isomers on a calix[4]arene column were investigated. The optimized supramolecular structures showed that there exist hydrogen bonding and π–π interactions for benzenediol, and for naphthol the π–π interactions dominate. Thermodynamic results from quantum chemistry calculations using DFT‐B3LYP/STO‐3G** basis set were consistent with the retention behaviors of benzenediol and naphthol positional isomers on the calix[4]arene column. This work will provide theoretical support for the design of new calixarene stationary phases.
Vom Remote‐Schneiden bis Lab on a Chip
Authors: Beyer Eckhard
Published: February 2008

Der 3. Internationale Workshop Faserlaser in Dresden war ein voller Erfolg. Bei der Gelegenheit ergab sich auch die Möglichkeit für ein Gespräch mit dem Direktor des Fraunhofer‐Instituts für Werkstoff‐ und Strahltechnik IWS, Professor Dr. Eckhard Beyer. LTJ Chefredakteur Andreas Thoß nutzte die Gelegenheit, um mit ihm über Zukunft und Vergangenheit des IWS zu sprechen.
Mit Faser‐ und Scheibenlasern zu neuen Anwendungen
Authors: Vollertsen Frank , Buschenhenke Frank , Neumann Steffen , Partes Knut
Published: February 2008

Faser‐ und Scheibenlaser sind heute in einem breiten Leistungsspektrum kommerziell verfügbar. Diese Laser ermöglichen aufgrund einer vergleichsweise hohen Strahlqualität und Leistungsdichte eine Vielzahl neuer Anwendungen, beispielsweise in den Bereichen des Schweißens und der Oberflächenveredelung.
Hochleistungfaserlaser im Schiffbau
Authors: Jasnau Ulf , Gaede Rainer
Published: February 2008

Die Vorteile von Festkörperlasern für den Schiffbau und für ähnliche Branchen, die durch die Herstellung von Großstrukturen geprägt sind, werden schon seit längerem untersucht. Wesentliche Grundlagen für den Einsatz solcher Strahlquellen auf Werften wurden in Rostock erarbeitet. Von dort ging auch der Impuls für den weltweit ersten Einsatz von Festkörperlasern in der Fertigung einer Werft aus: Seit November 2006 wird ein Hochleistungsfaserlaser mit einer Leistung von 6 kW auf der Aker Werft in Turku, Finnland, zum Verschweißen von Blechen zu Paneelen mit dem Laser‐MSG‐Hybridschweißen eingesetzt.
Differences in RBV strategic factors and the need to consider opposing factors in turnaround outcomes
Authors: Arend Richard J.
Published: February 2008

The resource‐based view‐related empirical literature has focused on one‐industry–one‐focal‐resource studies to provide support for its core tenets. We complement that literature with a first empirical analysis of multiple strategic factors, including opposing factors, and covering multiple industries, based on a recent survey of turnaround professionals. We focus on two issues. First, we explore what factor characteristics correlate to differences in the level of impact on firm performance that different types of factors have. Second, we explore the balance between opposing strategic factors (i.e., beneficial versus detrimental factors) relating to which turnaround outcome occurs. Copyright © 2008 John Wiley & Sons, Ltd.
Characterization of two series of nitrogen‐containing dendrimers by natural abundance 15N NMR
Authors: Deloncle Rodolphe , Coppel Yannick , Rebout Cyrille , Majoral Jean‐Pierre , Caminade Anne‐Marie
Published: February 2008

Two series of small generation dendrimers built with phosphorus atoms at each branching point and various types of nitrogen atoms at natural abundance of 15N within the branches are characterized by a gradient enhanced GHNMQC (gradient hydrogen–nitrogen multiple quantum coherence) 1H15N NMR technique. The first series contains two types of nitrogen atoms, included in phosphorhydrazone linkages (CHNNMeP(S)), whereas the second series contains four types of nitrogen atoms included in azobenzene linkages (ArNNAr′) in addition to the phosphorhydrazone. The influence of the trans/cis isomerization of the azo bond on the 15N NMR has also been studied. Despite the low solubility of the azobenzene‐containing dendrimers, which renders the detection of some signals difficult, 15N NMR appears as a very sensitive tool to detect chemical changes in the dendritic structure. Copyright © 2008 John Wiley & Sons, Ltd.
Improved waveform fidelity using local HYPR reconstruction (HYPR LR)
Authors: Johnson Kevin M. , Velikina Julia , Wu Yijing , Kecskemeti Steve , Wieben Oliver , Mistretta Charles A.
Published: February 2008

The recently introduced HYPR (HighlY constrained backPRojection) method allows reconstruction of serial images from highly undersampled data. In HYPR, individual timeframes are obtained via unfiltered backprojections of normalized sinograms using anatomical constraints provided by a composite image. Here we develop the idea of constraining the backprojected data further to a series of local regions of interest in order to decrease the corruption of local information by distant signals. HYPR LR (local reconstruction) permits the use of a longer temporal window in the formation of the composite image, resulting in increased signal‐to‐noise ratio and quantitative reconstruction accuracy. Unlike HYPR, the new HYPR LR method can be applied to images acquired with arbitrary k‐space trajectories. It is suitable for a broad range of medical imaging applications involving serial changes in image sequence, offering exciting new opportunities in the future. Magn Reson Med 59:456–462, 2008. © 2008 Wiley‐Liss, Inc.
31P NMR spectroscopy of phospholipid metabolites in postmortem schizophrenic brain
Authors: Komoroski Richard A. , Pearce John M. , Mrak Robert E.
Published: February 2008

Evidence has been accumulating that schizophrenia involves abnormalities in the composition and metabolism of cell membrane phospholipids (PLs) in the brain. In vivo 31P MRS has been used to measure the metabolic precursors and degradation products of PL metabolism in schizophrenia. Because in vivo line widths are substantially broader than in solution, only the broad phosphomonoester (PME) and phosphodiester bands, or partly resolved resonances of individual metabolites, are typically measured in vivo in the 31P spectrum. In addition to poor resolution, the relatively low signal‐to‐noise ratio (SNR) makes precise quantitation difficult. An alternative with substantially better resolution and precision for quantitation is high‐resolution NMR spectroscopy of extracts of samples from postmortem brain. Here we determine absolute concentrations of the individual PL metabolites phosphocholine (pc), phosphoethanolamine (pe), glycerophosphocholine (gpc), and glycerophosphoethanolamine in aqueous extracts of tissue from frontal, temporal, and occipital cortex of postmortem brain for schizophrenics, controls, and patients with other mental illnesses (psychiatric controls [PC]) using high‐resolution 31P NMR spectroscopy. For the complete groups, which included both males and females, there were no statistically significant differences for schizophrenics vs. controls for any of the four PL metabolites in any of the three brain regions. Trends (0.05 < P < 0.10) were noted for increased gpc in schizophrenia in all three regions. PC differed from both controls and schizophrenics in several measures. When only males were considered, gpc was significantly (P < 0.05) elevated in all three brain regions in schizophrenia. Magn Reson Med 59:469–474, 2008. © 2008 Wiley‐Liss, Inc.
Cartesian SENSE and k‐t SENSE reconstruction using commodity graphics hardware
Authors: Hansen Michael S. , Atkinson David , Sorensen Thomas S.
Published: February 2008

This study demonstrates that modern commodity graphics cards (GPUs) can be used to perform fast Cartesian SENSE and k‐t SENSE reconstruction. Specifically, the SENSE inversion is accelerated by up to two orders of magnitude and is no longer the time‐limiting step. The achieved reconstruction times are now well below the acquisition times, thus enabling real‐time, interactive SENSE imaging, even with a large number of receive coils. The fast GPU reconstruction is also beneficial for datasets that are not acquired in real time. We demonstrate that it can be used for interactive adjustment of regularization parameters for k‐t SENSE in the same way that one would adjust window and level settings. This enables a new way of performing imaging reconstruction, where the user chooses the setting of tunable reconstruction parameters, in real time, depending on the context in which the images are interpreted. Magn Reson Med 59:463–468, 2008. © 2008 Wiley‐Liss, Inc.
Multispectral imaging with three‐dimensional rosette trajectories
Authors: Bucholz Elizabeth K. , Song Jiayu , Johnson G. Allan , Hancu Ileana
Published: February 2008

Two‐dimensional intersecting k‐space trajectories have previously been demonstrated to allow fast multispectral imaging. Repeated sampling of k‐space points leads to destructive interference of the signal coming from the off‐resonance spectral peaks; on‐resonance data reconstruction yields images of the on‐resonance peak, with some of the off‐resonance energy being spread as noise in the image. A shift of the k‐space data by a given off‐resonance frequency brings a second frequency of interest on resonance, allowing the reconstruction of a second spectral peak from the same k‐space data. Given the higher signal‐to‐noise per unit time characteristic of a 3D acquisition, we extended the concept of intersecting trajectories to three dimensions. A 3D, rosette‐like pulse sequence was designed and implemented on a clinical 1.5T scanner. An iterative density compensation function was developed to weight the 3D intersecting trajectories before Fourier transformation. Three volunteers were scanned using this sequence and separate fat and water images were reconstructed from the same imaging dataset. Magn Reson Med 59:581–589, 2008. © 2008 Wiley‐Liss, Inc.
Comparative MR study of hepatic fat quantification using single‐voxel proton spectroscopy, two‐point dixon and three‐point IDEAL
Authors: Kim Hyeonjin , Taksali Sara E. , Dufour Sylvie , Befroy Douglas , Goodman T. Robin , Petersen Kitt Falk , Shulman Gerald I. , Caprio Sonia , Constable R. Todd
Published: February 2008

Hepatic fat fraction (HFF) was measured in 28 lean/obese humans by single‐voxel proton spectroscopy (MRS), a two‐point Dixon (2PD), and a three‐point iterative decomposition of water and fat with echo asymmetry and least‐squares estimation (IDEAL) method (3PI). For the lean, obese, and total subject groups, the range of HFF measured by MRS was 0.3–3.5% (1.1 ± 1.4%), 0.3–41.5% (11.7 ± 12.1), and 0.3–41.5% (10.1 ± 11.6%), respectively. For the same groups, the HFF measured by 2PD was −6.3–2.2% (−2.0 ± 3.7%), −2.4–42.9% (12.9 ± 13.8%), and −6.3–42.9% (10.5 ± 13.7%), respectively, and for 3PI they were 7.9–12.8% (10.1 ± 2.0%), 11.1–49.3% (22.0 ± 12.2%), and 7.9–49.3% (20.0 ± 11.8%), respectively. The HFF measured by MRS was highly correlated with those measured by 2PD (r = 0.954, P < 0.001) and 3PI (r = 0.973, P < 0.001). With the MRS data as a reference, the percentages of correct differentiation between normal and fatty liver with the MRI methods ranged from 68–93% for 2PD and 64–89% for 3PI. Our study demonstrates that the apparent HFF measured by the MRI methods can significantly vary depending on the choice of water–fat separation methods and sequences. Such variability may limit the clinical application of the MRI methods, particularly when a diagnosis of early fatty liver needs to be performed. Therefore, protocol‐specific establishment of cutoffs for liver fat content may be necessary. Magn Reson Med 59:521–527, 2008. © 2008 Wiley‐Liss, Inc.
Poly(phenylene sulfide)/low‐melting‐point metal composites. I. Transient viscoelastic properties and crystallization kinetics
Authors: Wu Defeng , Wu Lanfeng , He Juan , Zhang Ming , Yan Changhao
Published: February 2008

Poly(phenylene sulfide)/low‐melting‐point metal composites (PPSMs) with various loading levels were prepared by melt compounding. The nonisothermal crystallization behavior and transient viscoelastic properties were characterized by the DSC, POM, DMA, and parallel‐plate rheometer. The results reveal that the low‐melting‐point metal (LMPM) particles show nice dispersion at relative low content levels (< 30 wt %). The PPSMs composites present dual characteristics of both the filled polymer composite and polymer blend system in their transient viscoelastic behaviors, which results in occurrence of the stress overshoots with long relaxation time and nonzero residual stress especially at high shear levels. During the crystallization process, the presence of those deformable LMPM droplets facilitates the crystallization kinetics of PPS because of their flow‐promoting action. On the other hand, the LMPM has no heterogeneous nucleating effect and, only plays the role of inert filler, which results in the degradation of the crystal structure of PPS. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 677–690, 2008
Against the proposition: for the diagnosis of viral infections, commercial assays provide more reliable results than do in‐house assays
Authors: James Vivienne
Published: February 2008

There are no differences inherent in the design of commercial or in‐house assays and their early development is similar. The same principles apply and it is on the same criteria of accuracy, reproducibility and clinical relevance of results that all assays are judged. However, if there is sufficient uptake of a commercial assay, its strengths and any flaws soon become apparent and it will only be the best commercial assays that remain in the market. For the in‐house assays it is through comparability studies and external quality assessment (EQA) schemes that the best can be demonstrated, albeit this information is only accessible initially to the EQA provider and the laboratories using the assays. The EQA results described here support my supposition that, for the diagnosis of viral infections, commercial assays do not provide more reliable results than do in‐house assays. Copyright © 2008 John Wiley & Sons, Ltd.
Reconstruction of pristine morphology, flow, nutrient conditions and submerged vegetation of lowland river spree (Germany) from palaeomeanders
Authors: Hilt Sabine , Schönfelder Ilka , Rudnicka Ania , Carls Randi , Nikolaevich Nikolai , Sukhodolov Alexander , Engelhardt Christof
Published: February 2008

The European Water Framework Directive requires the definition of reference conditions for each type of surface waters as a base to establish a classification system in which deviations from this high quality status must be determined. In order to reconstruct pristine conditions in the lower river Spree we investigated palaeomeanders using palaeohydrological and palaeolimnological methods. The settlement history of this region suggests low anthropogenic impact for all periods before ∼700 cal AD. Three palaeomeanders representing the conditions of the late Sub‐boreal/early Sub‐atlantic were investigated. River width and depth at bankfull stage were reconstructed using cross‐sections of the meanders. Based on these data and experiments on the recent river, a parametric model was developed to calculate the bankfull palaeodischarge. Reconstructions show narrower and shallower channels for the undisturbed lower Spree (∼20 m mean width and 0.8 m mean depth at bankfull stage) as compared to recent conditions (35 m and 1.6 m, respectively). Flow velocities and discharge at bankfull stage have been smaller in reconstructed sub‐fossil channels (0.5 m s−1 and 8 m3 s−1 in the pristine lower Spree as compared to 0.9 m s−1 and 52 m3 s−1 in the recent lower Spree) and flow variability was higher. The increase in bankfull discharge was mainly attributed to deforestation and drainage of the catchment as well as channelization, bank protection and river regulation measures. The organic silt at the base of the sediment cores contained well‐preserved fossil diatom assemblages. Diatom‐inferred total phosphorus (DI‐TP) concentrations of 59–73 µg L−1 (median 62 µg L−1) indicate eutrophic to hypertrophic conditions and suggest naturally slightly lower nutrient levels than today. These past nutrient conditions, morphology and large numbers of macrofossil remains indicate optimum growth conditions for submerged macrophytes growth. The combination of palaeohydrological and palaeolimnological parameters proved to be a useful approach for the determination of pristine conditions in a lowland river. Copyright © 2008 John Wiley & Sons, Ltd.
Geomorphic effects of large wood jams on a sub‐antarctic mountain stream
Authors: Mao L. , Andreoli A. , Comiti F. , Lenzi M. A.
Published: February 2008

Dead wood pieces, especially when organized in jams, play an important geomorphic role in streams because of the effects on flow hydraulics, pool formation and sediments storage. The increase in stream morphological diversity and complexity also exerts an important ecological role. This work reports on geomorphic role of large wood (LW) pieces and jams in a third‐order mountain stream located in the Southern Tierra del Fuego (Argentina), and draining an old‐growth Nothofagus‐forested basin not influenced by the beavers damming activity. Even if the in‐stream number of wood pieces (length >1 m; diameter >0.1 m) is comparable to that observed in other climatic areas, the slow growth of the Nothofagus forest causes a lower wood abundance in terms of volumetric load. Because of the relatively small dimensions of the surveyed LW pieces, almost 70% of them demonstrated to have been fluvial transported and also the wood jams reflect the apparent dynamic nature of wood in the channel. Wood jams exert a significant influence on the channel morphology, representing almost half of the drop caused by steps and being responsible for the creation of 30% of the pools. LW‐forced pool volume is strongly and positively correlated to the height of the LW jam. The geomorphic influence of LW jams is also exerted by a considerable sediment storing capacity. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of dietary supplementation with increasing doses of docosahexaenoic acid on neutrophil lipid composition and leukotriene production in human healthy volunteers
Authors: Stanke-Labesque Françoise , Molière Patrick , Bessard Jeanine , Laville Martine , Véricel Evelyne , Lagarde Michel
Published: February 2008

n-3 PUFA supplementation helps in the prevention or treatment of inflammatory diseases and CVD. However, many supplementations reported so far are either a combination of n-3 PUFA or used large daily amounts of n-3 PUFA dosages. The present study investigated the influence of increasing dose intake of DHA on the fatty acid composition of phospholipids in neutrophils and on their capability to produce leukotrienes (LT) B4 and B5in vitro. Twelve healthy volunteers were supplemented with increasing daily doses of DHA (200, 400, 800 and 1600 mg, each dose in TAG containing DHA as the only PUFA and for a 2-week period). At the end of each supplementation period, neutrophil fatty acid composition, and LTB4 and LTB5 production were determined by GC and liquid chromatography–tandem MS, respectively. The DHA/arachidonic acid ratio increased in a dose-dependent manner with respect to the increasing doses of DHA supplementation and was significantly different from baseline after supplementation with either 400, 800 or 1600 mg DHA. The LTB5/LTB4 ratio was significantly increased compared to baseline after supplementation with 800 and 1600 mg DHA. LTB5/LTB4 and DHA/arachidonic acid ratios were correlated (r 0·531, P < 0·0001). The present data suggest that both changes in neutrophil lipid composition and LT production occurred with daily supplementation with 800 and 1600 mg DHA. The clinical benefits associated with these doses of DHA in inflammatory diseases remain to be investigated.
The Nitrogen Hypothesis and the English Agricultural Revolution: A Biological Analysis
Authors: ALLEN ROBERT C.
Published: February 2008

A biological model of nitrogen in agriculture is specified for early modern England and used to analyze the growth in grain yields from the middle ages to the industrial revolution. Nitrogen-fixing plants accounted for about half of the rise in yields; the rest came from better cultivation, seeds, and drainage. The model highlights the slow chemical reactions that governed the release of the nitrogen introduced by convertible husbandry and the cultivation of legumes. However efficient were England's institutions, nitrogen's chemistry implied that the English agricultural revolution would be much more gradual than the Green Revolution of the twentieth century.
Welfare State and Labor Mobility: The Impact of Bismarck's Social Legislation on German Emigration before World War I
Authors: KHOUDOUR-CASTÉRAS DAVID
Published: February 2008

The rapid decline of German emigration before World War I constitutes a puzzle that traditional explanations have difficulty in solving. The article shows that the social legislation implemented by Bismarck during the 1880s—the most developed at the time—played a key role in this process. Indeed, candidates for migration considered not only the gap between “direct wages” (labor earnings) in the United States and Germany, but also the differential in “indirect wages,” that is, social benefits. In that way, Bismarck's insurance system partly offset low wage rates in Germany and furthered the fall of the emigration rate.

O sprecht! warum zogt ihr von dannen?Das Neckartal hat Wein und Korn;Der Schwarzwald steht voll finstrer Tannen,Im Spessart klingt des Ålplers Horn.Wie wird es in den fremden WäldernEuch nach der Heimatberge Grün,Nach Deutschlands gelben Weizenfeldern,Nach seinen Rebenhügeln ziehn!Ferdinand Freiligrath1
Haupt- und Interaktionseffekte von Selbstkontrollanforderungen auf Indikatoren der Arbeitsbeanspruchung
Authors: Neubach Barbara , Schmidt Klaus-Helmut
Published: February 2008

Zusammenfassung. In der modernen Arbeitswelt wird verstärkt gefordert, dass Mitarbeiter ihr Verhalten flexibel an Unternehmenserfordernissen und Kundenwünschen ausrichten. Dies bedeutet gleichzeitig, dass von den Mitarbeitern Selbstkontrolle gefordert wird, um ihr Verhalten zielgerichtet zu steuern. Verschiedene Befunde weisen darauf hin, dass Anforderungen an die Selbstkontrolle eine spezifische Form der Arbeitsbelastung darstellen. In der vorliegenden Studie wurden die Effekte dreier Facetten geforderter Selbstkontrolle in Arbeitskontexten untersucht. Es konnte gezeigt werden, dass in einer Stichprobe von 549 Mitarbeitern einer Verwaltung Anforderungen an das “Überwinden innerer Widerstände”, die “Impulskontrolle” und das “Widerstehen von Ablenkungen” signifikante Zusammenhänge mit Indikatoren psychischer Beanspruchung aufweisen. Die Überprüfung von Wechselwirkungen der verschiedenen Selbstkontrollanforderungen ergab, dass hohe Anforderungen an das “Überwinden innerer Widerstände” die adversen Effekte der Anforderung “Impulskontrolle” verstärken. Dies spricht - im Sinne der Ego-Depletion-Theorie - dafür, dass Selbstkontrollanforderungen ein und dieselbe (Willens-)Ressource beanspruchen.
Spatial variability in the European winter precipitation δ18O‐NAO relationship: Implications for reconstructing NAO‐mode climate variability in the Holocene
Authors: Baldini Lisa M. , McDermott Frank , Foley Aideen M. , Baldini James U. L.
Published: February 2008

This paper investigates the links between precipitation δ18O and the North Atlantic Oscillation (NAO) on decadal timescales to identify the optimum locations within Europe at which to compile δ18O‐based proxy records of past NAO variability. δ18O is a commonly used paleoclimate (rainfall and temperature) proxy preserved in natural archives including stalagmites, ice cores, tree rings, and lake sediments. Precipitation δ18O data (δ18Op), compiled from Global Network of Isotopes in Precipitation (GNIP) stations in the North Atlantic sector reveal the direction and strength of the δ18Op‐NAO relationship in mid‐latitude, high‐latitude, and Mediterranean Europe. The highly significant, positive δ18Op‐NAO relationship in central Europe is attributed to the strong control of air temperature on δ18Op in this region. The δ18Op‐NAO relationship is strongly negative at high‐latitude GNIP sites and weak at Mediterranean sites. Decadal‐scale solar irradiance variations correlate with winter δ18Op at eight mid‐latitude sites.
Key points model for polar region currents
Authors: Xu Wen‐Yao , Chen Geng‐Xiong , Du Ai‐Min , Wu Ying‐Yan , Chen Bo , Liu Xiao‐Can
Published: February 2008

The equivalent ionospheric electric currents in the polar region mainly consist of the DP1 and DP2 systems. The former involves a westward electrojet around midnight, while the later involves a two‐cell system with foci on the morningside and eveningside, respectively. In space weather prediction and nowcasting, sophisticated models of the polar currents are needed, but concise and convenient models are also useful to predict or nowcast the principal characteristics of the current systems, such as intensity and position. In this paper, we propose a “key points model” for outlining the basic features of the polar region current system for different disturbance levels. The “key points model” (or KP model) includes six key points of the current system: the centers of two DP2 cells, the maximum densities of the eastward and westward electrojets, and the maximum densities of the northward and southward currents. Each of six key points is described by three parameters: intensity, local time, and latitude. The AE‐dependences of the 18 parameters are deduced from the equivalent current systems for every 5 min during a 2‐d period (18–19 March 1978). The KP model reveals systematic variations of the current systems. When AE increases, the currents and the current densities are simultaneously enhanced linearly, and most of the key points concentrate towards midnight. In addition, when AE increases, the key points K2 and K4 for the evening current cell move equatorward, while the key points K1 and K3 for morning cell move poleward.
Application of a nested‐grid ocean circulation model to Lunenburg Bay of Nova Scotia: Verification against observations
Authors: Zhai Li , Sheng Jinyu , Greatbatch Richard J.
Published: February 2008

A nested‐grid ocean circulation modeling system is used to study the response of Lunenburg Bay in Nova Scotia, Canada, to local wind‐forcing, tides, remotely generated waves, and buoyancy forcing in the summer and fall of 2003. Quantitative comparisons between observations and model results demonstrate that the modeling system reproduces reasonably well the observed sea level, temperature, salinity, and currents in the bay. Numerical results reveal that the spatial and temporal variability of temperature and salinity in the bay during the study period is mainly forced by the local wind stress and surface heat/freshwater fluxes, with some contribution from tidal circulation. In particular, the local heat balance on the monthly timescale is dominated by cooling due to vertical advection and warming due to horizontal advection and net surface heat flux, while high‐frequency variations (timescales of 1–30 days) are mainly associated with vertical advection, i.e., wind‐induced upwelling and downwelling. There is also a strong baroclinic throughflow over the deep water region outside Lunenburg Bay that is strongly influenced by wind‐forcing. The vertically integrated momentum balance analysis indicates a modified geostrophic balance on the monthly timescale and longer, and is dominated by the pressure term and wind minus bottom stress in the high‐frequency band.
Aerosol direct radiative effects over Kanpur in the Indo‐Gangetic basin, northern India: Long‐term (2001–2005) observations and implications to regional climate
Authors: Dey Sagnik , Tripathi S. N.
Published: February 2008

We present 5‐year (2001–2005) monthly mean estimates of direct radiative effects (DRE) due to aerosols over Kanpur region in the Indo‐Gangetic basin for the first time. Further, the monthly and annual heterogeneity of aerosol DRE has been evaluated on the basis of the anthropogenic and natural aerosol contribution. An optically equivalent model has been formulated on the basis of the surface measurements, altitude profiles of aerosol properties in conjunction with remotely retrieved aerosol parameters, and the optical properties are used to estimate the aerosol DRE at the top‐of‐atmosphere (TOA), surface and atmosphere in the shortwave (SW) and longwave (LW) region. Water‐solubles, black carbon (BC), and dust in fine (dustf) and coarse (dustc) mode are considered to be the main aerosol components on the basis of the chemical composition measurements. Anthropogenic components (scattering water‐solubles and absorbing BC) contribute more than 80% to the composite aerosol optical depth, AOD (at 0.5 μm) in the winter, whereas the natural dusts contribute more than 55% in the summer months. Aerosols induce large negative surface forcing (more than −20 W m−2) with higher values (more than −30 W m−2) during the premonsoon season, when the transported natural dusts add to the anthropogenic aerosol pollution. The SW surface cooling is partially (maximum up to 11%) compensated by LW surface heating. The SW cloudy‐sky aerosol DRE values are +1.4 ± 6.1, −23.3 ± 9.3 and +24.8 ± 9.7 W m−2 for TOA, surface and atmosphere, respectively. Annually ∼5% BC mass fraction contributes ∼9% to total AOD0.5, but ∼40% to the total aerosol surface DRE. The annual mean (±SD) TOA, surface and atmospheric clear‐sky SW anthropogenic aerosol DRE over Kanpur are +0.3 ± 2.5, −19.9 ± 9 and +20.2 ± 9.9 W m−2, respectively. Large negative surface forcing and positive atmospheric forcing in the Kanpur region raise several climatic issues. Anthropogenic aerosols contribute 65.4% to the mean (±SD) annual heating rate of 0.84 ± 0.3 K d−1 over Kanpur. A persistently large reduction of net surface radiation would affect the regional hydrological cycle through changes in evaporation and sensible heat flux. Our study assesses the aerosol direct radiative effects in Kanpur region for a 5 year period, which would provide a baseline to more thoroughly address these climate‐related issues in the future.
A 26 million year gap in the central Arctic record at the greenhouse‐icehouse transition: Looking for clues
Authors: Sangiorgi Francesca , Brumsack Hans‐Jürgen , Willard Debra A. , Schouten Stefan , Stickley Catherine E. , O'Regan Matthew , Reichart Gert‐Jan , Sinninghe Damsté Jaap S. , Brinkhuis Henk
Published: February 2008

The Cenozoic record of the Lomonosov Ridge (central Arctic Ocean) recovered during Integrated Ocean Drilling Program (IODP) Expedition 302 revealed an unexpected 26 Ma hiatus, separating middle Eocene (∼44.4 Ma) from lower Miocene sediments (∼18.2 Ma). To elucidate the nature of this unconformity, we performed a multiproxy palynological (dinoflagellate cysts, pollen, and spores), micropaleontological (siliceous microfossils), inorganic, and organic (Tetra Ether Index of lipids with 86 carbon atoms (TEX86) and Branched and Isoprenoid Tetraether (BIT)) geochemical analysis of the sediments from ∼5 m below to ∼7 m above the hiatus. Four main paleoenvironmental phases (A–D) are recognized in the sediments encompassing the unconformity, two below (A–B) and two above (C–D): (A) Below the hiatus, proxies show relatively warm temperatures, with Sea Surface Temperatures (TEX86‐derived SSTs) of about 8°C and high fresh to brackish water influence. (B) Approaching the hiatus, proxies indicate a cooling trend (TEX86‐derived SSTs of ∼5°C), increased freshwater influence, and progressive shoaling of the Lomonosov Ridge drilling site, located close to or at sea level. (C) The interval directly above the unconformity contains sparse reworked Cretaceous to Oligocene dinoflagellate cysts. Sediments were deposited in a relatively shallow, restricted marine environment. Proxies show the simultaneous influence of both fresh and marine waters, with alternating oxic and anoxic conditions. Pollen indicates a relatively cold climate. Intriguingly, TEX86‐derived SSTs are unexpectedly high, ∼15–19°C. Such warm surface waters may be partially explained by the ingression of warmer North Atlantic waters after the opening of the Fram Strait during the early Miocene. (D) Sediments of the uppermost interval indicate a phase of extreme oxic conditions, and a well‐ventilated environment, which occurred after the complete opening of the Fram Strait. Importantly, and in contrast with classical postrifting thermal subsidence models for passive margins, our data suggest that sediment erosion and/or nondeposition that generated the hiatus was likely due to a progressive shoaling of the Lomonosov Ridge. A shallow water setting both before and after the hiatus suggests that the Lomonosov Ridge remained at or near sea level for the duration of the gap in the sedimentary record. Interacting sea level changes and/or tectonic activity (possibly uplift) must be invoked as possible causes for such a long hiatus.
18.7 GHz tropospheric scintillation and simultaneous rain attenuation measured at Spino d'Adda and Darmstadt with Italsat
Authors: Matricciani Emilio , Riva Carlo
Published: February 2008

We present experimental results on the relationship between rain attenuation and simultaneous scintillation, obtained with measurements of attenuation time series at 18.7 GHz, collected in two slant paths to Italsat (13.2° E): at Spino d'Adda (Italy, a 37.7° slant path, times series of 50 samples/s and 1 sample/s) and Darmstadt (Germany, a 32.7° slant path, 1 sample/s). We have found that the average rain attenuation A (dB) and the average standard deviation σm (dB) in 1‐min intervals (calculated from the 1 sample/s time series), of the scintillation standard deviation σ (dB), are linked by a power law σm = C3aA, or by the more refined model σm = C3bA, that can be due to an effective thin layer of turbulence aloft. The constants C3a,3b can be estimated by applying the ITU−R formula for scintillation predictions. For conservative design, a best fit model of the conditional standard deviation of σ is also provided, as a function of A, as σs = CsAd (dB), where Cs and d are constants.
Racial/ethnic Differences in Body Fatness Among Children and Adolescents
Authors: Freedman David S. , Wang Jack , Thornton John C. , Mei Zuguo , Pierson Richard N. , Dietz William H. , Horlick Mary
Published: February 2008

Background: Although the BMI is widely used as a measure of adiposity, it is a measure of excess weight, and its association with body fatness may differ across racial or ethnic groups.

Objective: To determine whether differences in body fatness between white, black, Hispanic, and Asian children vary by BMI‐for‐age, and whether the accuracy of overweight (BMI‐for‐age ≥ Centers for Disease Control and Prevention (CDC) 95th percentile) as an indicator of excess adiposity varies by race/ethnicity.

Methods and Procedures: Total body dual‐energy X‐ray absorptiometry (DXA) provided estimates of %body fat among 1,104 healthy 5‐ to 18‐year‐olds.

Results: At equivalent levels of BMI‐for‐age, black children had less (mean, 3%) body fatness than white children, and Asian girls had slightly higher (1%) levels of %body fat than white girls. These differences, however, varied by BMI‐for‐age, with the excess body fatness of Asians evident only among relatively thin children. The ability of overweight to identify girls with excess body fatness also varied by race/ethnicity. Of the girls with excess body fatness, 89% (24/27) of black girls, but only 50% (8/16) of Asian girls, were overweight (P = 0.03). Furthermore, the proportion of overweight girls who had excess body fatness varied from 62% (8/13) among Asians to 100% (13/13) among whites.

Discussion: There are racial or ethnic differences in body fatness among children, but these differences vary by BMI‐for‐age. If race/ethnicity differences in body fatness among adults also vary by BMI, it may be difficult to develop race‐specific BMI cut points to identify equivalent levels of %body fat.
Interpolating moving least-squares methods for fitting potential energy surfaces: A strategy for efficient automatic data point placement in high dimensions
Authors: Dawes Richard , Thompson Donald L. , Wagner Albert F. , Minkoff Michael
Published: February 2008

An accurate and efficient method for automated molecular global potential energy surface (PES) construction and fitting is demonstrated. An interpolating moving least-squares (IMLS) method is developed with the flexibility to fit various ab initio data: (1) energies, (2) energies and gradients, or (3) energies, gradients, and Hessian data. The method is automated and flexible so that a PES can be optimally generated for trajectories, spectroscopy, or other applications. High efficiency is achieved by employing local IMLS in which fitting coefficients are stored at a limited number of expansion points, thus eliminating the need to perform weighted least-squares fits each time the potential is evaluated. An automatic point selection scheme based on the difference in two successive orders of IMLS fits is used to determine where new ab initio data need to be calculated for the most efficient fitting of the PES. A simple scan of the coordinate is shown to work well to identify these maxima in one dimension, but this search strategy scales poorly with dimension. We demonstrate the efficacy of using conjugate gradient minimizations on the difference surface to locate optimal data point placement in high dimensions. Results that are indicative of the accuracy, efficiency, and scalability are presented for a one-dimensional model potential (Morse) as well as for three-dimensional (HCN), six-dimensional (HOOH), and nine-dimensional (CH4) molecular PESs.
Density functional study of double ionization energies
Authors: Chong D. P.
Published: February 2008

In this paper, double ionization energies (DIEs) of gas-phase atoms and molecules are calculated by energy difference method with density functional theory. To determine the best functional for double ionization energies, we first study 24 main group atoms in the second, third, and fourth periods. An approximation is used in which the electron density is first obtained from a density functional computation with the exchange-correlation potential Vxc known as statistical average of orbital potentials, after which the energy is computed from that density with 59 different exchange-correlation energy functionals Exc. For the 24 atoms, the two best Exc functional providing DIEs with average absolute deviation (AAD) of only 0.25eV are the Perdew–Burke–Ernzerhof functional modified by Hammer et al. [Phys. Rev. B 59, 6413 (1999)] and one known as the Krieger–Chen–Iafrate–Savin functional modified by Krieger et al. (unpublished). Surprisingly, none of the 20 available hybrid functionals is among the top 15 functionals for the DIEs of the 24 atoms. A similar procedure is then applied to molecules, with opposite results: Only hybrid functionals are among the top 15 functionals for a selection of 29molecules. The best Exc functional for the 29molecules is found to be the Becke 1997 functional modified by Wilson et al. [J. Chem. Phys. 115, 9233 (2001)]. With that functional, the AAD from experiment for DIEs of 29molecules is just under 0.5eV. If the two suspected values for C2H2 and Fe(CO)5 are excluded, the AAD improves to 0.32eV. Many other hybrid functionals perform almost as well.
Effects of surface passivation on the exciton dynamics of CdSe nanocrystals as observed by ultrafast fluorescence upconversion spectroscopy
Authors: Kippeny Tadd C. , Bowers Michael J. , Dukes Albert D. , McBride James R. , Orndorff Rebecca L. , Garrett Maria Danielle , Rosenthal Sandra J.
Published: February 2008

The exciton dynamics of CdSe nanocrystals are intimately linked to the surface morphology. Photo-oxidation of the selenium surfaces of the nanocrystal leads to an increase in radiative decay efficiency from both the band edge and deep trap emission states. The addition of the primary amine hexadecylamine curtails nonradiative excitonic decay attributed to the dangling surface selenium orbitals by passivation of those trap sites by the methylene protons on the amine, leading to enhanced band edge emission and the absence of deep trap emission. Furthermore, CdSe∕ZnSe core/shell nanocrystals are not immune from contributions from surface states because of the alignment of the band structures of the core and shell materials.