bluuebunny/crossref_metadata_2025 huggingface dataset:
Imagining Life Under the Long Shadow of 9/11: Backlash, Media Discourse, Identity and Citizenship of the Bangladeshi Diaspora in the United States
Authors: Rahman Shafiqur
Published: May 2010

In this article I examine how the Bangladeshi diaspora in the United States, a predominantly first-generation Muslim immigrant group, reacted to the post-9/11 backlash, and articulated their identity and citizenship. Although in the wake of 9/11 backlash the Bangladeshi-Americans felt the pressure to think their life and identity in a binary Muslim vs American term, they refused to accept that identity not only because they do not fit into that fixed categorization, but also because it curtails their ability to engage in society in multiple terms and exert their citizenship rights. The ‘forced’ awakening of religious identity eventually turned into a political awareness, invoking critical questions about citizenship in the post-9/11 environment.
“Let Them Eat Harmony”
Authors: Dixon John , Tropp Linda R. , Durrheim Kevin , Tredoux Colin
Published: May 2010

Research on intergroup prejudice has generally adopted a model of social change that is based around the psychological rehabilitation of members of advantaged groups in order to foster intergroup harmony. Recent studies of prejudice-reduction interventions among members of disadvantaged groups, however, have complicated psychologists’ understanding of the consequences of inducing harmonious relations in historically unequal societies. Interventions encouraging disadvantaged-group members to like advantaged-group members may also prompt the disadvantaged to underestimate the injustice suffered by their group and to become less motivated to support action to challenge social inequality. Thus, psychologists’ tendency to equate intergroup harmony with “good relations” and conflict with “bad relations” is limited.
Representations in Visual Cognition
Authors: van Zoest Wieske , Hunt Amelia R. , Kingstone Alan
Published: May 2010

Visual cognition relies on changing representations of visual information. The dynamic nature of representations is demonstrated by new findings in human perception and attention showing that the influence of specific aspects of a stimulus on behavior changes dramatically over time. As a consequence, performance depends on what point in time responses are measured. Specifically, quick responses to early representations of a new scene are heavily influenced by the relative salience of different stimuli in the visual field. Slow responses based on later representations of the same scene are informed by more complex information that integrates prior knowledge and observer goals. Thus, as a result of the dynamic nature of representations, the kind of information that is prioritized depends on the moment in time the representation is accessed. Examining how representations change over time can lead to new and important insights in a wide range of domains of human cognition.
The Motivation–Cognition Interface in Learning and Decision Making
Authors: Todd Maddox W. , Markman Arthur B.
Published: May 2010

In this article we discuss how incentive motivations and task demands affect performance. We present a three-factor framework that suggests that performance is determined from the interaction of global incentives, local incentives, and the psychological processes needed to achieve optimal task performance. We review work that examines the implications of the motivation–cognition interface in classification and choice and on phenomena such as stereotype threat and performance pressure. We show that, under some conditions, stereotype threat and pressure accentuate performance. We discuss the implications of this work for neuropsychological assessment and outline a number of challenges for future research.
Preschool Depression
Authors: Luby Joan L.
Published: May 2010

The empirical finding that school-aged children could suffer clinical depression refuted the widely held assumption that this age group would be too developmentally immature to experience depressive symptoms. Currently childhood depression is a well-recognized and widely treated clinical disorder. Following more recent developmental findings emphasizing the emotional sophistication of very young children, scientific studies have demonstrated that depression can arise early in life, during the preschool period of development. Preschool depression is characterized by typical symptoms of depression such as anhedonia; changes in sleep, appetite, and activity level; and excessive guilt. Further, longitudinal continuity of preschool depression into school age has been established, suggesting that preschool depression is an early manifestation of the later childhood disorder. Based on the known efficacy of early developmental intervention in a number of domains and disorders related to the greater neuroplasticity of the brain earlier rather than later in childhood, it is important to identify depression at the earliest possible point. Early intervention strategies for preschool depression that focus on enhancing emotional development are currently being tested.
A Cognitive Experimental Approach to Understanding and Reducing Food Cravings
Authors: Kemps Eva , Tiggemann Marika
Published: May 2010

Food cravings are a common everyday experience. Yet, they can pose significant health risks for some people. Following initial investigations into the phenomenology, antecedents, and consequences of food cravings, recent scientific interest has turned to the underpinnings of the actual craving experience. In this article, we outline a conceptual framework for studying food cravings that is grounded in cognitive experimental psychology and describe our corresponding program of research. In particular, we present converging evidence from a number of seemingly disparate lines of research into the cognitive processes that underlie food cravings with a view to developing a craving-reduction technique.
The Time Course of Interpretation in Speech Comprehension
Authors: Dahan Delphine
Published: May 2010

Determining how language comprehension proceeds over time has been central to theories of human language use. Early research on the comprehension of speech in real time put special emphasis on the sequential property of speech, by assuming that the interpretation of what is said proceeds at the same rate that information in the speech signal reaches the senses. The picture that is emerging from recent work suggests a more complex process, one in which information from speech has an immediate influence while enabling later-arriving information to modulate initial hypotheses. “Right-context” effects, in which the later portion of a spoken stimulus can affect the interpretation of an earlier portion, are pervasive and can span several syllables or words. Thus, the interpretation of a segment of speech appears to result from the accumulation of information and integration of linguistic constraints over a larger temporal window than the duration of the speech segment itself. This helps explain how human listeners can understand language so efficiently, despite massive perceptual uncertainty in the speech signal.
Health Care, Aviation, and Ecosystems
Authors: Durso Francis T. , Drews Frank A.
Published: May 2010

Efforts to improve the delivery of health care have led scholars to look to other safety-critical industries for comparisons that may serve as models. We flesh out one popular comparison: aviation, an industry made exceptionally safe in large part due to the efforts of applied experimental and applied social psychologists. A number of aspects of the aviation industry are similar to those of health care. However, there are also limitations of the analogy, and we suggest that any analogy to an engineered system like that of aviation will capture only some aspects of the health-care system. We suggest health care is a socio-natural system and thus invites interventions appropriate for ecosystems.
Chronic Depression
Authors: Klein Daniel N.
Published: May 2010

Traditionally, non-bipolar depression has been viewed as an episodic, remitting condition. However, with the recognition that depressions can persist for many years, the current diagnostic classification system includes various forms of chronic depression. The distinction between chronic and nonchronic depressions is useful for reducing the heterogeneity of the disorder. Individuals with chronic depression differ from those with nonchronic depression on a variety of clinically and etiologically significant variables, including comorbidity, impairment, suicidality, history of childhood maltreatment, familial psychopathology, and long-term course. In contrast, there is little support for current distinctions between different forms of chronic depression. This suggests that it may be simpler to collapse the existing forms of chronic depression in the current classification system into a single category. However, there is growing evidence that other characteristics, such as age of onset and a childhood history of early adversity, may provide meaningful approaches to subtyping chronic depression.
The British navy’s 1888 budgetary reforms
Authors: Cobbin Phillip E. , Burrows Geoff H.
Published: May 2010

Reforms to the British navy’s estimates for 1888—9 radically changed the way that budgetary information was presented to parliament. Motivated by a desire to facilitate efficiency judgments about public expenditure, in the new-style estimates expenditure was classified according to object or purpose rather than on the basis of the traditional subjective categorizations. These reforms were instituted, in the face of strong Treasury opposition, almost as a fait accompli, by Mr Arthur Forwood (later Sir Arthur Forwood, Bt), Parliamentary and Financial Secretary to the Navy, supported by his senior minister, Lord George Hamilton, First Lord of the Admiralty, both of whom possessed unusually advanced ideas about public-sector efficiency and management. The article examines the background to and nature of the reforms and the unusual dynamics of the reform process, as well as attempting to ascertain their wider place in the history of governmental budgeting and accounting.
So many controls; so little control: The case of Isaac Henderson, Navy Agent at New York, 1861-4
Authors: Mayer-Sommer Alan P.
Published: May 2010

The experience of one man, Isaac Henderson, provides the lens through which this study examines the operation during the Civil War of the federal expenditure control system of the USA. This system’s requisitioning, disbursing and auditing activities cannot be disentangled from the patronage system and profiteering that inevitably accompany war. Surging activity levels brought on by the war only aggravated the existing weaknesses. Rigidities, redundancies and formalities within the Treasury Department delayed disbursement processing and the subsequent auditing of those disbursements. Clerks who approved disbursements also audited the same disbursements. The focus on appropriation accounting — rather than on information for planning and control purposes — reflected the view that controls existed primarily to assure Congress and the public that money was spent in conformity with laws and regulations. Improper charges were sometimes intentionally placed against appropriations with available balances. Thus the most significant contribution of the federal expenditure control system may well have been to help legitimize wartime spending to Congress and the American people.
Colonel William Henry Sykes: His contribution to statistical accounting
Authors: Talbot Philip A.
Published: May 2010

In “Genealogies of Calculation”, Miller and Napier (1993) engaged with the alternative boundaries of calculation beyond traditional accounting histories. This was justified because not all forms of calculation are to be found in accounting. The removal of this accounting limitation encouraged investigation into other calculative technologies in order to widen the accounting history agenda. This challenge is now taken up through the genealogical examination of the mutation of political arithmetic into statistics and then as accounting statistics as employed by the British military and its relationship with the British brewing industry. In particular, the focus is on the work of Colonel William Henry Sykes, a seminal member of the early Victorian Statistical Movement with his statistical accounting analysis of the British and French Armies of 1864 and later employment of this technique in the financial management of the Bass Rifle Volunteers.
Cost-benefit analysis in correspondence related to building the Rideau Canal
Authors: Bujaki Merridee L.
Published: May 2010

The relationship between government and the military is examined through the use of cost-benefit analysis (CBA) statements included in correspondence related to building the Rideau Canal. Discourse analysis is used to identify and evaluate CBA statements. CBA statements are used for rhetorical, technical and reporting purposes. Rhetorical uses of CBA predominate in the period leading up to the construction of the Rideau Canal. CBA as a tool for decision-making of a technical nature is common during the construction of the canal. CBA serves both rhetorical and technical purposes in progress reports. Patterns in the use of CBA in correspondence between government and military are also analysed and reveal a number of communication channels where communication using CBA statements between government and the military is either common or is lacking.
Considering the fetish value of EOD robots
Authors: Roderick Ian
Published: May 2010

This article explores how the Explosive Ordnance Disposal (EOD) robot is represented to the mass media by the US military as a ‘life-saving device’. Such descriptions of the EOD robot discursively organize it in relation to other objects and actors, endow them with values and capacities, and ultimately situate them in social action. Drawing from US newspaper articles and Department of Defense press releases, the article highlights how the robot descriptions create a sense of automation and agency on the part of the remote-controlled devices that is actually beyond the technology. It is then argued that the IED-combating robot functions as a kind of fetish. Following Baudrillard, the fetish value of the robot stems not from a misunderstanding of its actual or ‘real’ capacities but rather its positive valuation according to a code of functionality that rests upon the risk-transfer labour of the robot.
Azteca America’s performance of Mexicanness in the pan-Hispanic television market
Authors: Beck Chad Thomas
Published: May 2010

The US Spanish-language television and advertising industries have assimilated their audiences into a homogeneous pan-ethnic market, yet this article argues that the newest network, Azteca America, has contested this homogenization by pursuing Mexican viewers. Surveying network practices, this article shows how the market’s pan-Hispanic paradigm has restrained Azteca America from positioning itself as decidedly Mexican. Drawing upon ethnographic evidence and performance theory, this article particularly examines how the network accomplishes its cultural positioning through its ‘upfront’ events, the annual pre-broadcast happenings for advertising clients. Azteca America’s performance of Mexicanness displays Mexican immigrants as domestic consumers but cultural foreigners and, hence, non-citizens. Nevertheless, the network’s practices register a hybrid, transborder Mexican culture and occasionally critique sociopolitical disenfranchisement of Mexican immigrants.
Influence of petrophysical and geotechnical engineering properties on the electrical response of unconsolidated earth materials
Authors: Boadu Fred Kofi , Owusu-Nimo Frederick
Published: May 2010

We have investigated the influence of petrophysical and geotechnical engineering properties of unconsolidated near-surface geomaterials (soils) on their electrical responses or measurements. Complex resistivity measurements were performed at a constant effective stress on 32 samples of varying textures and compositions. Petrophysical and engineering properties that inherently affect the mechanical and strength behavior of the samples — that is, fines content, pore-size parameter, specific surface area, and fractal dimension of the grain-size distributions — were obtained from geotechnical analysis. The electrical parameters that describe the electrical response of the samples — that is, resistivity amplitude [Formula: see text], phase shift [Formula: see text], percent frequency effect (PFE), loss tangent [Formula: see text], and the normalized phase [Formula: see text] — are computed from the electrical measurements. Crossplots of the electrical and engineering parameters provide useful infor-mation on how the geotechnical properties of the soil material influence the electrical measurements. In particular, [Formula: see text] and [Formula: see text] values are strongly influenced by variations in the petrophysical and engineering properties [Formula: see text] in comparison with the other electrical parameters. Soils become more dissipative as their specific surface area increases. The PFE values are less sensitive [Formula: see text] to the petrophysical and engineering properties. Analysis of the correlations also indicates that characteristic or transitional values of the fines content (18%) and pore size [Formula: see text] exist, beyond which the phase and normalized phase values are insensitive to their respective increases. The characteristic value of 18% fines content is close to values reported in previous studies, which signifies transition in strength behavior of soils and, thus, such relations could be important in noninvasive strength assessment and monitoring of soils. Normalized phase values were used to assess the relative amount of fines in the studied soils.
HOW YOU GUYS Doin'? STAGED ORALITY AND EMERGING PLURAL ADDRESS IN THE TELEVISION SERIESFRIENDS
Authors: Heyd Theresa
Published: May 2010

This study explores the sociolinguistics of mediated discourse and the use of “staged orality” in such genres. It involves a corpus-driven approximation of you guys as an emerging quasi pronoun for second-person plural address based on dialogue transcriptions of the sitcom Friends. With its 10-year time span and close interactions between its six young New Yorkers, the Friends corpus is a good locus to monitor linguistic variation and change. An overall analysis reveals that you guys is much more frequent here than in other genres and shows a modest increase over time. Syntactically, you guys is found to increase in more involved constructions. In terms of gender, you guys is shown to be equally distributed between men and women—both with regard to the speakers' identity and to the semantic referent. In sum, these findings shed light both on you guys as a candidate for second-person plural address and on the specific discursive conditions of the staged orality found in genres such as television sitcoms.
Detection of the Heterochirality of a 1:2 Metal/Ph-pybox Complex Ion by ESIMS
Authors: Sato Hirofumi , Suzuki Yoshitomo , Takai Yoshio , Kawasaki Hideya , Arakawa Ryuichi , Shizuma Motohiro
Published: May 2010

The heterochirality of a 1:2 metal/Ph-pybox complex ion was encyclopedically evaluated by ESIMS using pseudo-racemic (R,R)- and (S,S)-Ph-pybox pair, which were unlabeled/labeled by deuterium atoms, respectively. The heterochiral complex was predominantly formed in all investigated 1:2 metal/Ph-pybox complex ions.
Kinetic Analysis of Reduction of Formyl Groups in Chlorophyll d and Pheophytin d
Authors: Sadaoka Kana , Hirai Yuki , Kashimura Shigenori , Saga Yoshitaka
Published: May 2010

Reduction of formyl groups in natural chlorophyll (Chl) d purified from a cyanobacterium, Acaryochloris marina, and its demetalation product, pheophytin (Phe) d, was kinetically analyzed. Chl d exhibited slower reduction kinetics of the formyl group to the hydroxymethyl group by tert-butylamine borane complex than Phe d.
A Novel Protein Gel Route to Synthesize Luminescent Lu3Al5O12:Ce3+ Powders Calcined at Lower Temperature
Authors: Yu Dao , Liu Qingfeng , Liu Qian
Published: May 2010

A novel protein gel method was developed to synthesize composite oxide phosphors, in which ovalbumin was used as gelling agent. By this route, Lu3Al5O12:Ce3+ powders were obtained at 700 °C with a size of less than 50 nm. Under ultraviolet excitation, the emission peak is located around 510 nm. This simple method is applicable to high-throughput synthesis.
Extraordinary Effect of Microwave Irradiation on Asymmetric Catalysis
Authors: Kikuchi Satoshi , Tsubo Tatsuyuki , Ashizawa Tomoko , Yamada Tohru
Published: May 2010

We here report the effect of microwave irradiation on the atropo-enantioselective ring-opening reaction of biaryl lactones with dynamic–kinetic resolution catalyzed by AgBF4–phosphine complexes. The multimode microwave reactor with a cooling system was employed and the fiber-optic sensor was used for measurement of the accurate internal reaction temperature. It was found that the reaction was accelerated by microwave irradiation without any loss of enantioselectivity at almost the same internal temperature as the conventional conditions.
Amino Acid Spin Labels. An Application of Chelation Ability to a Nickel(II) Ion
Authors: Osada Sayaka , Igarashi Kazuki , Nogami Takashi , Ishida Takayuki
Published: May 2010

NN–CH2-substituted l-alanine methyl ester (NNCH2–l-Ala–OMe) and β-alanine ethyl ester (NNCH2–β-Ala–OEt) were prepared, where NN stands for 4,4,5,5-tetramethylimidazolin-1-oxyl 3-oxide. Their nickel(II) perchlorate complexes with a metal/ligand ratio of 1/2 were structurally and magnetically characterized.
Thermodynamic Study of the Solvation States of Acid and Base in a Protic Ionic Liquid, Ethylammonium Nitrate, and Its Aqueous Mixtures
Authors: Kanzaki Ryo , Song Xuedan , Umebayashi Yasuhiro , Ishiguro Shin-ichi
Published: May 2010

Ethylammonium nitrate (EAN) is a typical protic ionic liquid (PIL) known for a long time. In order to investigate acid–base reaction mechanisms in PIL, thermodynamic quantities of a reaction, which corresponds to autoprotolysis in amphoteric solvents, has been determined in neat EAN. Unlike H3O+ and OH− in water, proton donor and acceptor species in EAN are both neutral; this makes acid–base reaction mechanisms in EAN distinct from that in water. EAN–water mixtures have also been studied.
Aspects of the Nonlinear Optical Properties as a Guide to Protonation Sites: A Theoretical Study upon α-Keggin [SiW12O40]4− and [SiV3W9O40]7−
Authors: Yao Chan , Liu Chun-Guang , Yan Li-Kai , Guan Wei , Song Ping , Su Zhong-Min
Published: May 2010

The present study focuses on probing the extent to which nonlinear optical effects act as a guide to protonation sites of α-Keggin heteropolyanions [SiW12O40]4− and [SiV3W9O40]7−. The second-harmonic generation (SHG) values of differently protonated forms predict that the molecular nonlinear optical activity has a close relationship with protonation sites and provides a new potential experimental probe.
Synthesis of Hollow Silica Nanospheres Templated by Micelles of Poly{styrene-b-[3-(methacryloylamino)propyl]trimethylammonium chloride-b-ethylene oxide}
Authors: Liu Jingjing , Liu Dian , Manickam Sasidharan , Yokoyama Yuuichi , Yusa Shin-ichi , Nakashima Kenichi
Published: May 2010

A micelle of poly{styrene-b-[3-(methacryloylamino)propyl]trimethylammonium chloride-b-ethylene oxide} with core–shell–corona architecture in aqueous solutions has been successfully applied to the synthesis of hollow silica nanospheres as a new template. Tetramethoxysilane, phenyltrimethoxysilane, and their mixtures were used as silica precursors and the ratio of the precursor to the template influences the shell thickness of the obtained hollow silica.
Solid-state Solvatochromic Behavior of Reichardt’s Dye Crystals Hybridized with Silica Nanoparticles
Authors: Ichimura Kunihiro , Funabiki Akira , Aoki Ken’ichi
Published: May 2010

The dry bead milling of solvatochromic ET30 with silica nanoparticles gave powdery nanohybrids, which exhibited color changes depending on environmental conditions.
Facile Fabrication and Magnetic Properties of Macroporous Spinel Microspheres from Layered Double Hydroxide Microsphere Precursor
Authors: Zhang Fazhi , Xie Yaru , Xu Sailong , Zhao Xiaofei , Lei Xiaodong
Published: May 2010

Macroporous CoFe2O4 spinel microspheres have been fabricated by a simple process involving calcination of layered double hydroxide microsphere precursor, which was originally prepared by spray drying with polystyrene as template.
Erratum to “Buy Now and Match Later: Impact of Posterior Price Matching on Profit with Strategic Consumers”
Authors: Lai Guoming , Debo Laurens G. , Sycara Katia
Published: May 2010

On page 37 of the article “Buy Now and Match Later: Impact of Posterior Price Matching on Profit with Strategic Consumers” by Guoming Lai, Laurens Debo, and Katia Sycara Manufacturing & Service Operations Management, Winter 2010, Vol. 12, No. 1, 33–55) , to the beginning of §3.4 Purchasing Behavior, the following sentence should be added:

“Similar to Png (1991), we assume that the consumers will make no purchase if the price is higher than VH and thus the seller will not set the first-period price above VH in our model. Furthermore….”

The assumption that p1 ≤ VH was made, but was not stated explicitly in the model set-up section.
Dynamics of seagrass and macroalgal assemblages in Saipan Lagoon, Western Pacific Ocean: disturbances, pollution, and seasonal cycles
Authors: Houk Peter , Camacho Rodney
Published: May 2010

Despite a wealth of laboratory experiments describing seagrass growth and competitive interactions with macroalgae under varying nutrient concentrations, there is limited information available from field studies conducted in complex natural environments. We examined ecological change over time in the Saipan Lagoon, Western Pacific Ocean. Here, seagrass (Halodule uninervis) canopy cover was quantified monthly at relatively small spatial scales over a 3-year period. Where watershed size and human population were low, there was a significant relationship with seasonal environmental cycles; cooler temperatures correlated with increased drift, red algal abundance and freshwater input increased green algae. Following cyclical macroalgal overgrowth, however, seagrass again became the dominant canopy. Conversely, in the presence of high human population and urbanization, seasonal cycles were absent and a seagrass-to-macroalgal transition was evident. Adjacent to a large watershed with moderate pollution, significant ties were found between seagrass emergence and winter-time disturbance events (large swells), as detached macroalgae that formed during summer months were removed annually. In summary, seagrass systems associated with Saipan Lagoon appear to be hierarchically controlled, following: 1) disturbances, 2) land-based pollution, and 3) seasonal environmental cycles.
Salinity tolerance of Rhizophora mucronata Lam. from Gujarat coasts of India
Authors: Patel Neha T. , Yadav Dipak R. , Ghosh Dilipkumar , Pandey Amar N.
Published: May 2010

Greenhouse experiments were conducted to assess the effects of soil salinity on germination, growth, water status, proline content and mineral accumulation of seedlings of Rhizophora mucronata (Rhizophoraceae). NaCl was added to the soil and salinity was maintained at 0.2, 2.5, 5.1, 7.7, 10.3, 12.6, 15.4, 17.9, 20.5, 23.0 and 25.6 psu. This plant is highly salt tolerant at the germination stage. Growth of seedlings was significantly promoted by low salinity and optimum growth was obtained at 20.5 psu. Moreover, higher salinities inhibited plant growth. Water potential of tissues became significantly more negative with increase in salinity. Proline content in tissues significantly increased as salinity increased. The concentration of Na in tissues increased, whereas K, Ca, N and P content decreased with increase in salinity. We discuss changes in tissues and whole-plant accumulation patterns of other nutrients, as well as possible mechanisms for avoidance of Na toxicity in this plant in response to salinity.
Mechanical Conditioning of Superelastic Nitinol Wire for Improved Fatigue Resistance
Authors: Schaffer Jeremy E.
Published: May 2010

Metallic wire used in medical devices contains small defects that must be accounted for in design to guard against failure. Sites of probable failure are often constituent inclusion particles, pores, or surface defects that behave as crack-like, stress concentrators. The aim of this research is to examine the effects of mechanical overload conditioning applied to medical-grade nitinol wire on fatigue performance. A mechanical overload conditioning treatment comprising a single axial tensile strain cycle of 11.5 % was applied at room temperature (300 K) to nominally Ti 50.9 at. % Ni wires with active Af 280 K. The conditioning strain cycle was applied to both plain wire samples with only process and melt-intrinsic defects and to samples which were milled by focused ion beam to produce a transverse 10×0.5×3 μm notch. Transmission electron microscopy was used to probe the root of the milled notch before and after overload conditioning in order to ascertain microstructural parameters responsible for property changes. Evidence of a plasticity-locked, mixed-phase, microstructure at the sharp defect root was found after conditioning. Samples were loaded in a rotary beam fatigue apparatus and cycled in air at 60 s−1 to a maximum of 109 cycles. The fatigue strain limit was increased by more than 20 % at 107 cycles in the conditioned versus non-conditioned plain wire.
Regelung von rotierenden Blutpumpen zur Linksherzunterstützung
Authors: Arndt Andreas , Nüsser Peter , Lampe Bernhard P.
Published: May 2010

Es wird ein physiologischer Regelalgorithmus für ein kontinuierlich förderndes Herzunterstützungssystem vorgestellt. Die Regelung erfolgt auf der Basis der vom System INCOR gelieferten Messwerte des Differenzdruckes. Dabei wird die Pulsatilität des Differenzdruckes auf einen Sollwert geregelt. Die Vorgabe des Sollwertes erfolgt automatisch durch Identifikation und Einstellung eines der klinischen Indikation entsprechenden Arbeitspunktes.
Intraoperative Navigation bei Bypassoperationen am offenen Herzen
Authors: Dietmayer Klaus , Hartung Christine , Quester Claudia , Hoffmann Martin , Friedl Reinhard
Published: May 2010

Bypassoperationen am offenen Herzen werden als Standardtherapie bei fortgeschrittener koronarer Herzkrankheit durchgeführt. Ziel eines solchen Eingriffes ist es, Engstellen der Herzkranzgefäße mit Gefäßtransplantaten zu überbrücken. Eine der Herausforderungen während der Operation ist die optimale Positionierung des Bypasses auf dem erkrankten Gefäß. Um den Chirurgen bei dieser Aufgabe zu unterstützen, wurden im Rahmen des Cardio-Pointer Projekts Verfahren für computergestützte Bypasschirurgie am offenen Herzen entwickelt, die die intraoperative Navigation mit einem Zeigeinstrument (Cardio-Pointer) zu einer präoperativ geplanten optimalen Bypassstelle sowohl am schlagenden als auch am stillgelegten Herzen ermöglichen. Das entwickelte Gesamtsystem wurde an zwölf Patienten im Rahmen einer klinischen Studie evaluiert.
Adaptive Patientenunterstützung für Rehabilitationsroboter
Authors: Duschau-Wicke Alexander , Morger André , Vallery Heike , Riener Robert
Published: May 2010

Rehabilitationsroboter unterstützen die Rehabilitation von Patienten mit Bewegungsstörungen aufgrund von Schädigungen des Nervensystems. Neu entwickelte, patientenkooperative Regelungsansätze sollen es diesen Robotern ermöglichen, individuell an die Patienten angepasste, effektivere Trainingseinheiten durchzuführen, als dies bislang möglich war. Dieser Beitrag beschreibt zwei Ansätze zur automatischen Anpassung der Roboterunterstützung: Die iterativ lernende Vorsteuerung ermöglicht die Unterstützung von Bewegungen mit definiertem zeitlichem Ablauf. Das iterativ lernende, konservative Kraftfeld ermöglicht die Unterstützung von Bewegungen mit freiem zeitlichem Ablauf. Das Verhalten beider Verfahren wird an einer Beispielanwendung mit dem Gang-Rehabilitationsroboter Lokomat demonstriert.
Automatisierung und Fehlerdiagnose bei der extrakorporalen Membranoxygenierung
Authors: Walter Marian , Stollenwerk André , Wartzek Tobias , Arens Jutta , Kopp Rüdiger , Leonhardt Steffen
Published: May 2010

Die Extrakorporale Membranoxygenierung ist eine der letzten Therapieoptionen für schwere Fälle eines akuten Lungenversagens. Hierzu wird Blut in einem externen Kreislauf ähnlich einer Herz-Lungen-Maschine durch einen Oxygenator gepumpt. In diesem findet ein zusätzlicher Gasaustausch statt. Im Gegensatz zum Einsatz im Operationssaal wird die länger andauernde Therapie auf der Intensivstation in der Regel nicht kontinuierlich durch einen Kardiotechniker überwacht. Die in diesem Beitrag vorgestellten Konzepte für Automatisierung und Fehlerdiagnose sind ein wichtiger Schritt hin zu einem sicheren und zuverlässigen teil-autonomen Betrieb eines Systems, das sich den individuellen Bedürfnissen des Patienten kontinuierlich anpasst.
Development of gamma spectrometric method for the determination of thorium in phosphoric acid solution
Authors: Mirashi N. N. , Chaudhury Satyajeet , Aggarwal S. K.
Published: May 2010

Gamma spectrometric determination of thorium in sintered thoria dissolved in strong phosphoric acid was studied using a high purity germanium (HPGe) detector. 232Th was determined using the highly abundant (27%) gamma ray (911.4 keV) emitted by its daughter 228Ac. The count rates in peak regions were plotted against the amount of thorium present in thorium nitrate working standard solution to obtain a calibration curve and the extent of thoria dissolved in 88% phosphoric acid was determined. Further studies on determination of thorium were carried out using thorium phosphate solutions, instead of using thorium nitrate working standard solutions. The solution of thorium phosphate obtained after quantitative dissolution of thoria in 88% phosphoric acid was also found to give a linear calibration curve at 911.4 keV. Using the calibration curves, expected count rates for thorium in sintered thoria dissolved in 88% phosphoric acid were calculated and were in good agreement (±3%) with the observed count rates.
An Additive Long-range Potential to Correct for the Charge-transfer Failure of Time-dependent Density Functional Theory
Authors: Dreuw Andreas , Plötner Jürgen , Wormit Michael , Head-Gordon Martin , Dutoi Anthony Dean
Published: May 2010

Time-dependent density functional theory is one of the most widely used methods for the calculation of excited states of large molecules. However, it exhibits substantial problems with charge-transfer excited states when conventional exchange-correlation functionals are employed. Here, we introduce an additive long-range potential that can, in principle, be directly employed with any existing local, GGA or hybrid-functional, without re-fitting of the original functionals. The additive potential shifts the excitation energies to higher values and corrects for the wrong asymptotic behavior of their potential energy surfaces with respect to charge-separating coordinates. First examples of its successful application are shown.
Density-Functional Theory with Orbital-Dependent Functionals: Exact-exchange Kohn-Sham and Density-Functional Response Methods
Authors: Görling Andreas , Ipatov Andrey , Götz Andreas W. , Heßelmann Andreas
Published: May 2010

Kohn-Sham methods with orbital-dependent exchange-correlation functionals, in particular exact-exchange methods, are discussed. The numerical stability of optimized-effective-potential methods to construct the exchange-correlation potential in the case of orbital-dependent energy functionals is considered. A numerically stable exact-exchange Kohn-Sham method is briefly presented. A new ansatz for time-dependent density-functional methods in the response regime is considered and an exact-exchange time-dependent density-functional method based on it is discussed and it is demonstrated that this methods is able to treat qualitatively correctly charge-transfer excitations.
Recent Advances in Explicitly Correlated Coupled-Cluster Response Theory for Excited States and Optical Properties
Authors: Hättig Christof , Yang Jun
Published: May 2010

The derivation of coupled-cluster response theory for explicitly correlated wavefunctions with terms linear in the interelectronic distance r
12 (CC-R12) or a function f
12 thereof (CC-F12) is reviewed and an implementation at the CCSD(R12) and CCSD(F12) for excitation energies and the linear, quadratic and cubic reponse functions is reported for ansätze 1 and 2. We discuss the results of first applications for vertical excitation energies, excited state equilibrium structures and vibrational frequencies, polarizabilities and first and second hyperpolarizabilities with focus on present limitations and future prospects of the approach. We show in particular that the standard choice of the geminal functions and wavefunction expansion can in certain cases lead to a bias towards the unperturbed ground state and how this can be avoided by extending the geminal space. If taken care of this, in particular CCSD(F12)/ansatz 2 shows for the potential energy curves of excited states and for optical properties a similar enhanced basis set convergence of the correlation contribution due to connected double excitations as for ground state energies. For diffuse excited states and hyperpolarizbilities the correlation contribution converges with CCSD(F12)/ansatz 2 often faster than orbital relaxation contributions. The convergence of the latter can be improved by allowing single excitations into a space spanned by a complementary auxiliary basis set.
A Linear-Scaling MP2 Method for Large Molecules by Rigorous Integral-Screening Criteria
Authors: Doser Bernd , Zienau Jan , Clin Lucien , Lambrecht Daniel S. , Ochsenfeld Christian
Published: May 2010

A brief review of our linear-scaling method for atomic-orbital (AO) second-order Møller-Plesset perturbation theory (MP2) is given. The key feature of our method is the rigorous preselection of numerically significant four-center two-electron integrals based on multipole-based integral estimates (MBIE) that do not only account for the exponential coupling between the Gaussian-type basis functions forming charge distributions, but also for the 1/R coupling between the charge distributions. This coupling turns for the required integral products in AO-MP2 into at least a 1/R4 or even a 1/R6 decay behavior. Using MBIE we attain linear scaling, which is illustrated for DNA fragments with up to 1052 atoms and 10 674 basis functions as computed on a single processor. The largest molecule calculated in our present work at the scaled-opposite spin (SOS-) AO-MP2 level is an RNA system comprising 1664 atoms and 19 182 basis functions. Furthermore, we present results for the use of Cholesky-decomposed pseudo-density matrices in Laplace-based MP2, that offers the advantage of exploiting occupied/virtual blocking both with and without auxiliary basis sets.
A Quasirelativistic Two-component Density Functional and Hartree-Fock Program
Authors: Wüllen Christoph van
Published: May 2010

This work describes the implementation of an efficient two-component quasirelativistic density functional and Hartree-Fock program. The fact that the basis functions are real can be exploited if a special internal representation of operators and density matrices is used. This also leads to a considerable reduction of the effort in the closed shell case. While in most applications to open shell molecules, the noncollinear approach to define a relativistic spin density is preferable, the collinear approach finds its application in the calculation of magnetic anisotropy energies. Linear algebra steps in the SCF procedure have a higher relative weight compared to the nonrelativistic case, therefore some care was necessary to make them fast when parallelizing the code. The quasirelativistic Hamiltonians that have been implemented are the ´zeroth-order regular approximation´ (ZORA) Hamiltonian, the Douglas-Kroll-Hess Hamiltonian up to the sixth order, together with an accurate approximation to treat the picture change effect of the electron interaction, and effective core potential (ECP) matrix elements. Geometry gradients are available for the ZORA and ECP methods.
Second Order Local Møller-Plesset Perturbation Theory for Periodic Systems: the CRYSCOR Code
Authors: Usvyat Denis , Maschio Lorenzo , Pisani Cesare , Schütz Martin
Published: May 2010

This article reviews the periodic LMP2 method and its implementation in the CRYSCOR code. The main steps of the LMP2 calculations and the techniques employed are briefly described. Illustrative single-point calculations for three TiO2 polymorphs: rutile, anatase and brookite in their experimental geometry are performed. It is shown that the method scales linearly with respect to the number of atoms per unit cell, and can be applied to relatively complex periodic systems. The LMP2 method in contrast to DFT positions rutile slightly lower in the energy than anatase. Brookite is found to be the most stable. However, since the energy differences are relatively small, a further investigation of the influence of the domain-sizes, geometry, zero-point vibrations, etc. on the relative stability of these systems is required.
Orbital-dependent Representation of Correlation Energy Functional
Authors: Jiang H. , Engel E.
Published: May 2010

Exchange-correlation energy functionals depending on the Kohn-Sham orbitals and eigenvalues resolve some of the well-known deficiencies of the local density and generalized gradient approximations. Such functionals can be derived in first-principles fashion by use of standard many-body techniques, if the Kohn-Sham Hamiltonian is utilized as non-interacting reference Hamiltonian. In this way one can establish an exact relation for the exchange-correlation functional, which opens several routes for the derivation of approximate functionals. Straightforward expansion in powers of the electron-electron coupling constant gives, to first order, the exact exchange of density functional theory and, to second order, a correlation functional which has the same structure as the second order Møller-Plesset term. This simplest first-principles correlation functional reproduces both the shell structure in the exact correlation potential and dispersion forces. On the other hand, it overestimates all correlation effects and is variationally instable for systems with a very small HOMO-LUMO gap. Both deficiences can be resolved by partial resummation of the Kohn-Sham perturbation expansion. In this contribution two such resummations are discussed, a minimum form designed to address the variational instability at no computational cost (based on the Epstein-Nesbet diagrams) and a more systematic variant (based on the ring diagrams).
Coupling of Short-range Density-functional with Long-range Post-Hartree-Fock Methods
Authors: Goll Erich , Werner Hans-Joachim , Stoll Hermann
Published: May 2010

A review is given on recent work with range-separated hybrid density-functional approaches, using accurate wavefunction-based ab initio methods for the treatment of the long-range inter-electronic interaction. It is shown that in many cases results can be improved with respect to the borderline methods, since the hybrid approach is less basis-set dependent than in the pure ab initio case, and deficiencies of pure DFT for weak interactions are efficiently removed. However, there is still need for improvement of currently available short-range density functionals.
Benchmark Studies for Explicitly Correlated Perturbation- and Coupled Cluster Theories. javascript:filterformular(´3´)
Authors: Werner Hans-Joachim , Knizia Gerald , Adler Thomas B. , Marchetti Oliver
Published: May 2010

The recently developed explicitly correlated MP2-F12 and CCSD(T)-F12x (x = a,b) methods are reviewed. The explicit correlation treatment leads to a dramatic improvement of the basis set convergence. Extensive benchmarks for reaction energies, atomization energies, electron affinities, ionization potentials, equilibrium structures, vibrational frequencies, and intermolecular interaction energies are presented which show that for many molecular properties the intrinsic accuracy of the CCSD(T) method is already reached with double-zeta (VDZ-F12) basis sets, while triple-zeta (VTZ-F12) basis sets yield results that are very close to the complete basis set limit. The steep scaling of the MP2-F12 method with molecular size can be reduced by local approximations. This has made it possible to carry out MP2-F12 calculations for molecules with up to 100 atoms. The errors caused bjavascript:filterformular(´3´)y the local domain approximation are largely removed by the explicitly correlated terms, which account for the neglected configurations in an approximate way. Extensions to LCCSD(T)-F12 are discussed and preliminary results for LCCSD-F12 are presented.
Fully Automated Implementation of the Incremental Scheme for Correlation Energies
Authors: Friedrich Joachim , Hanrath Michael , Dolg Michael
Published: May 2010

The applicability and performance of a fully automated implementation of the incremental scheme for the evaluation of correlation contributions in wavefunction-based quantum chemical calculations on large molecules is briefly reviewed and a typical example from organic chemistry is discussed in more detail. The accuracy of relative energies is analyzed for various water hexamers at the CCSD(T)/aug-cc-pVDZ level. Furthermore the accuracy of the potential energy surface of octane is analyzed at the CCSD level of theory. Finally, CCSD(T)/aug-cc-pVTZ calculations with 1656 basis functions in C1 symmetry are reported for (H2O)18, where a full calculation is infeasible within reasonable time.
On Occupied-orbital Dependent Exchange-correlation Functionals: From Local Hybrids to Becke’s B05 Model
Authors: Kaupp Martin , Arbuznikov Alexei , Bahmann Hilke
Published: May 2010

Recent work in the field of occupied-orbital dependent (OOD) exchange-correlation functionals in density functional theory is reviewed. The main emphasis is put on the development of so-called local hybrid functionals, and on the nontrivial self-consistent implementation of complex OOD functionals. Local hybrids employ a so-called local mixing function (LMF) to govern their position-dependent exact-exchange admixture. Recently proposed LMFs have provided local hybrids of remarkable accuracy in the computation of thermochemical data and classical reaction barriers, and with good performance for some magnetic-resonance parameters. These local hybrids mix only local and exact exchange and exhibit very few semi-empirical parameters. Further refinement and the efficient implementation of local hybrids offers the prospect of a new level of accuracy in Kohn-Sham density functional calculations. Two levels of the self-consistent implementation of OOD functional are discussed: one may either stop after the derivation of the functional derivatives with respect to the orbitals (FDOs), leading to nonlocal potentials. This is discussed for local hybrids and for general OOD functionals up to and including the complicated B05 real-space model of nondynamical correlation. Alternatively, one may append an additional transformation to local and multiplicative potentials based on the optimized effective potential (OEP) approach or of approximations to the OEP. Numerical results for various properties are reviewed briefly, ranging from nonself-consistent energies via FDO-based calculations to OEP-transformed potentials.
The Density Matrix Renormalization Group Algorithm in Quantum Chemistry
Authors: Marti Konrad Heinrich , Reiher Markus
Published: May 2010

In this work, we derive the density matrix renormalization group (DMRG) algorithm in the language of configuration interaction. Furthermore, the development of DMRG in quantum chemistry is reviewed and DMRG-specific peculiarities are discussed. Finally, we discuss new results for a dinuclear μ-oxo bridged copper cluster, which is an important active-site structure in transition-metal chemistry, an area in which we pioneered the application of DMRG.