bluuebunny/crossref_metadata_2025 huggingface dataset:
β‐amyloid and postural instability and gait difficulty in Parkinson's disease at risk for dementia
Authors: Müller Martijn L.T.M. , Frey Kirk A. , Petrou Myria , Kotagal Vikas , Koeppe Robert A. , Albin Roger L. , Bohnen Nicolaas I.
Published: December 2012

Although motor impairments in Parkinson's disease (PD) are attributed to nigrostriatal dopaminergic denervation, postural instability and gait difficulty (PIGD) features are less responsive to dopaminergic medications. PIGD features are a risk factor also for the development of dementia in PD (PDD). These observations suggest that nondopaminergic mechanisms may contribute to axial motor impairments. The aim was to perform a correlative PET study to examine the relationship between neocortical β‐amyloid deposition ([11C]‐Pittsburgh Compound B), nigrostriatal dopaminergic denervation ([11C]‐dihydrotetrabenazine), and PIGD feature severity in PD patients at risk for dementia. This was a cross‐sectional study of 44 PD patients (11 female and 33 male; 69.5 ± 6.6 years of age; 7.0 ± 4.8 years motor disease duration; mean H & Y stage: 2.7 ± 0.5) who underwent PET, motor feature severity assessment using the Movement Disorder Society revised UPDRS, and the Dementia Rating Scale (DRS). Linear regression (R2adj = 0.147; F4,39 = 2.85; P = 0.036) showed that increased PIGD feature severity was associated with increased neocortical [11C]‐Pittsburgh Compound B binding (β = 0.346; t39 = 2.13; P = 0.039) while controlling for striatal [11C]‐dihydrotetrabenazine binding, age, and DRS total score. Increased neocortical β‐amyloid deposition, even at low‐range levels, is associated with higher PIGD feature severity in PD patients at risk for dementia. This finding may explain why the PIGD motor phenotype is a risk factor for the development of PDD. © 2012 Movement Disorder Society
Extracting MRS discriminant functional features of brain tumors
Authors: Fuster‐Garcia Elies , Tortajada Salvador , Vicente Javier , Robles Montserrat , García‐Gómez Juan M.
Published: December 2012

The current challenge in automatic brain tumor classification based on MRS is the improvement of the robustness of the classification models that explicitly account for the probable breach of the independent and identically distributed conditions in the MRS data points. To contribute to this purpose, a new algorithm for the extraction of discriminant MRS features of brain tumors based on a functional approach is presented. Functional data analysis based on region segmentation (RSFDA) is based on the functional data analysis formalism using nonuniformly distributed B splines according to spectral regions that are highly correlated. An exhaustive characterization of the method is presented in this work using controlled and real scenarios. The performance of RSFDA was compared with other widely used feature extraction methods. In all simulated conditions, RSFDA was proven to be stable with respect to the number of variables selected and with respect to the classification performance against noise and baseline artifacts. Furthermore, with real multicenter datasets classification, RSFDA and peak integration (PI) obtained better performance than the other feature extraction methods used for comparison. Other advantages of the method proposed are its usefulness in selecting the optimal number of features for classification and its simplified functional representation of the spectra, which contributes to highlight the discriminative regions of the MR spectrum for each classification task. Copyright © 2012 John Wiley & Sons, Ltd.
Transient computational fluid dynamics modeling of pervaporation separation of aromatic/aliphatic hydrocarbon mixtures using polymer composite membrane
Authors: Rezakazemi Mashallah , Iravaninia Mona , Shirazian Saeed , Mohammadi Toraj
Published: December 2012

Pervaporation (PV) separation of toluene/n‐heptane mixtures was studied experimentally and theoretically by means of a molecular surface engineering (MSE) polymer composite membrane. A comprehensive mathematical model was developed to predict unsteady state transport of toluene and n‐heptane (nC7) through the membrane. Conservation equations including continuity, and heat transfer equations were solved using finite element method (FEM). Computational fluid dynamics (CFD) technique was applied to solve the model equations. The model was then verified with PV experimental data. The simulation results were in good agreement with the experimental data. The simulation results revealed that the proposed model could provide a general simulation of transport in the PV process. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Coaxial electrospun encapsulation of epoxy for use in self‐healing materials
Authors: Mitchell Timothy J , Keller Michael W
Published: December 2012

Epoxy was sequestered within a poly(vinyl alcohol) (PVA) shell using a coaxial electrospinning process resulting in fibers suitable for use in self‐healing materials. Electrospinning equipment was designed and built including extensive development of the coaxial spinneret and optimization of the electrical field. Other parameters that were studied and controlled included the viscosity of the shell material and the interfacial tension between the shell and core material. The interfacial tension between the PVA solution and the epoxy was controlled by adding ethanol to the water solvent. A concentration of 8.5 wt% PVA in a combined ethanol and water solution (water:EtOH = 1:0.15) yielded a PVA solution that had interfacial tension and viscosity characteristics that were effective for coaxial electrospinning. The resulting coaxially electrospun fibers assumed a beaded fiber morphology. © 2012 Society of Chemical Industry
Assessing Fear‐avoidance Beliefs in Patients with Cervical Radiculopathy
Authors: Dedering Åsa , Börjesson Tina
Published: December 2012

Background and Purpose

The study sought to evaluate validity and reliability of the Fear Avoidance Beliefs Questionnaire and the Tampa Scale for Kinesiophobia in patients with cervical radiculopathy.

Methods

A test–retest design was used to test stability over time in 46 patients with cervical radiculopathy. Differences between patients and healthy subjects were also evaluated comparing the patients with 41 physically active and healthy subjects. The patients answered the Fear Avoidance Beliefs Questionnaire and the Tampa Scale for Kinesiophobia twice. To test for differences between the patients and the healthy subjects, the latter answered the same questionnaires once. Questionnaires about activity, personal factors and health were also used.

Results

The test–retest reliability assessed with weighted kappa was 0.68 for the Fear Avoidance Beliefs Questionnaire and 0.45 for the Tampa Scale for Kinesiophobia. Only six of the 11 single items of the Fear Avoidance Beliefs Questionnaire and none of the single items of the Tampa Scale of Kinesiophobia showed kappa coefficients exceeding 0.60 (good reliability). Patients with cervical radiculopathy rated significantly worse on the Fear Avoidance Beliefs Questionnaire and the Tampa Scale for Kinesiophobia than the healthy subjects did.

Conclusions

The Fear Avoidance Beliefs Questionnaire may be recommended for test–retest evaluations because ‘good’ reliability was found. The Tampa Scale for Kinesiophobia had only ‘moderate’ test–retest reliability, and this should be considered when using this scale in test–retest evaluations. Both questionnaires can discriminate between patients with cervical radiculopathy and healthy subjects. Copyright © 2012 John Wiley & Sons, Ltd.
Arrays of low‐temperature plasma probes for ambient ionization mass spectrometry
Authors: Dalgleish Jon K. , Wleklinski Michael , Shelley Jacob T. , Mulligan Christopher C. , Ouyang Zheng , Graham Cooks R.
Published: December 2012

RATIONALE

This paper reports the development of arrays of capillary‐based low‐temperature plasma (LTP) probes for direct sample analysis. These probe arrays allow a higher surface area to be analyzed, increasing the throughput in large sample analysis. Validation of these arrays was performed on illicit, cathinone‐based drugs marketed as 'bath salts'.

METHODS

LTP arrays consisting of 1, 7, and 19 probes were constructed with quartz capillaries and held together with silver epoxy resin adhesive. Three drugs, mephedrone, methylone and methylenedioxypyrovalerone, were analyzed with each plasma ion source and an ion trap mass spectrometer in full MS and in MS/MS positive ion mode. Chemical and thermal footprints were determined for each source. A reactive probe design was used to inject trifluoroacetic anhydride directly into the plasma stream for on‐line derivatization.

RESULTS

Small LTP probes and bundled arrays provide low picogram level limits of detection for mephedrone, methylone and methylenedioxypyrovalerone. Bundling the probes together in larger arrays increases the surface area analyzed by a factor of ten, while maintaining surface temperatures below 40 °C. Selectivity towards mephedrone and methylone was increased using trifluoracetylation under ambient ionization conditions.

CONCLUSIONS

Low‐temperature plasma ionization sources allow rapid detection of illicit 'bath salt' drugs in low amounts. The sources have a larger sampling area that allows faster detection of each analyte, and selectivity towards the selected drug is enhanced by adding reagents directly into the plasma stream. Copyright © 2012 John Wiley & Sons, Ltd.
Structure‐fragmentation relationship and rapid dereplication of Buxus steroidal alkaloids by electrospray ionization‐quadrupole time‐of‐flight mass spectrometry
Authors: Musharraf Syed Ghulam , Goher Madiha , Shahnaz Salma , Choudhary M. Iqbal , Atta‐ur‐Rahman
Published: December 2012

RATIONALE

Tandem mass spectrometric studies of natural products revealed the identification of key fragments which can be helpful for their rapid dereplication in plant extracts utilizing a liquid chromatography/tandem mass spectrometry (LC/MS/MS) approach, particularly for the thermally labile compounds. The knowledge of the collision‐induced dissociation (CID) fragmentation pattern of the molecule is essentially required prior to the analysis by LC/MS/MS.

METHODS

The fragmentation patterns of eleven Buxus steroidal alkaloids were studied by using a positive ion electrospray ionization quadrupole time‐of‐flight mass spectrometry (ESI‐QqTOF‐MS/MS) hybrid instrument. Chromatographic separation of a Buxus papillosa extract was achieved using a capillary HPLC system coupled with the mass instrument.

RESULTS

ESI‐QqTOF‐MS (positive ion mode) showed the presence of several characteristic fragments which can be used to rapidly identify various classes of Buxus steroidal alkaloids. The presence of a cyclopropane ring in the cycloartenol skeleton and the hydroxyl group at C‐10 was found to effect on the fragmentation pattern and afford characteristic peaks. This study distinguishes between different types of Buxus steroidal alkaloids based on logical fragmentation pathways. This strategy was successfully applied in LC/ESI‐QqTOF‐MS/MS analysis of Buxus papillosa extract to investigate and characterize Buxus steroidal alkaloids and 14 compounds were identified as steroidal alkaloids.

CONCLUSIONS

The knowledge of the fragmentation pattern was used for the rapid identification of this bioactive group of biosynthetically unique steroidal alkaloids in complex plant extracts of Buxus species, especially in the absence of any reference material, by combining key fragments, exact mass measurements and relative abundances of diagnostic fragment ions. Copyright © 2012 John Wiley & Sons, Ltd.
Determination of 17O‐excess of terrestrial silicate/oxide minerals with respect to Vienna Standard Mean Ocean Water (VSMOW)
Authors: Tanaka Ryoji , Nakamura Eizo
Published: December 2012

RATIONALE

Oxygen triple isotope compositions give key information for understanding physical processes during isotopic fractionation between the geo‐, hydro‐, bio‐, and atmosphere. For detailed discussion of these topics, it is necessary to determine precise 17O‐excess values of terrestrial silicate/oxide minerals with respect to Vienna Standard Mean Ocean Water (VSMOW).

METHODS

Water was fluorinated in an electrically heated Ni‐metal tube into which water and BrF5 were loaded for the quantitative extraction of oxygen. Silicate/oxide minerals were fluorinated by heating with a CO2 laser in an atmosphere of BrF5. The extracted oxygen was purified and isotope ratios of the oxygen triple isotope compositions were determined using a Finnigan MAT253 isotope ratio mass spectrometer.

RESULTS

The oxygen triple isotope compositions of meteoric water and terrestrial silicate/oxide minerals fall on statistically distinguishable fractionation lines, defined as [ln(δ17O + 1) = λln(δ18O + 1) + Δ], where λ and Δ correspond to the slope and intercept, respectively. The fractionation line for meteoric water has λ = 0.5285 ± 0.0005 and Δ = 0.03 ± 0.02‰ and for terrestrial silicate/oxide minerals has λ = 0.5270 ± 0.0005 and Δ = –0.070 ± 0.005‰, at the 95% confidence limit.

CONCLUSIONS

All the analyzed terrestrial silicate/oxide minerals including internationally accepted reference materials (NBS‐28, UWG‐2, and San Carlos olivine) have a negative 17O‐excess with respect to VSMOW. We propose that it is necessary to specify if the determined δ17O values of terrestrial and extraterrestrial samples are expressed as the difference from VSMOW or the terrestrial silicate mineral‐corrected value. Copyright © 2012 John Wiley & Sons, Ltd.
Effective Theories and Theory Choice
Authors: Wells James D.
Published: December 2012

Promoting a theory with a finite number of terms into an effective field theory with an infinite number of terms worsens simplicity, predictability, falsifiability, and other attributes often favored in theory choice. However, the importance of these attributes pales in comparison with consistency, both observational and mathematical consistency, which propels the effective theory to be superior to its simpler truncated version of finite terms, whether that theory be renormalizable (e.g., Standard Model of particle physics) or unrenormalizable (e.g., gravity). Some implications for the Large Hadron Collider and beyond are discussed, including comments on how directly acknowledging the preeminence of consistency can affect future theory work.
Mutations in the AGXT2L2 gene cause phosphohydroxylysinuria
Authors: Veiga‐da‐Cunha Maria , Verhoeven‐Duif Nanda M. , de Koning Tom J. , Duran Marinus , Dorland Bert , Van Schaftingen Emile
Published: December 2012

Phosphohydroxylysinuria has been described in two patients with neurological symptoms, but the deficient enzyme or mutated gene has never been identified. In the present work, we tested the hypothesis that this condition is due to mutations in the AGXT2L2 gene, recently shown to encode phosphohydroxylysine phospholyase. DNA analysis from a third patient, without neurological symptoms, but with an extreme hyperlaxicity of the joints, shows the existence of two mutations, p. Gly240Arg and p.Glu437Val, both in the heterozygous state. Sequencing of cDNA clones derived from fibroblasts mRNA indicated that the two mutations were allelic. Both mutations replace conserved residues. The mutated proteins were produced as recombinant proteins in Escherichia coli and HEK293T cells and shown to be very largely insoluble, whereas the wild‐type one was produced as a soluble and active protein. We conclude that phosphohydroxylysinuria is due to mutations in the AGXT2L2 gene and the resulting lack of activity of phosphohydroxylysine phospholyase in vivo. The finding that the nul alleles of p.Gly240Arg and p.Glu437Val are present at low frequencies in the European and/or North American population suggests that this condition is more common than previously thought. The diversity of the clinical symptoms described in three patients with phosphohydroxylysinuria indicates that this is most likely not a neurometabolic disease.
Assessing Item Fit for Unidimensional Item Response Theory Models Using Residuals from Estimated Item Response Functions
Authors: Haberman Shelby J. , Sinharay Sandip , Chon Kyong Hee
Published: December 2012

Residual analysis (e.g. Hambleton & Swaminathan, Item response theory: principles and applications, Kluwer Academic, Boston, 1985; Hambleton, Swaminathan, & Rogers, Fundamentals of item response theory, Sage, Newbury Park, 1991) is a popular method to assess fit of item response theory (IRT) models. We suggest a form of residual analysis that may be applied to assess item fit for unidimensional IRT models. The residual analysis consists of a comparison of the maximum-likelihood estimate of the item characteristic curve with an alternative ratio estimate of the item characteristic curve. The large sample distribution of the residual is proved to be standardized normal when the IRT model fits the data. We compare the performance of our suggested residual to the standardized residual of Hambleton et al. (Fundamentals of item response theory, Sage, Newbury Park, 1991) in a detailed simulation study. We then calculate our suggested residuals using data from an operational test. The residuals appear to be useful in assessing the item fit for unidimensional IRT models.
Sphingolipid Content in the Human Uterus and Pair‐Matched Uterine Leiomyomas Remains Constant
Authors: Paweł Knapp , Chabowski Adrian , Górski Jan
Published: December 2012

In the present work we sought to investigate the content of sphingolipids (sphingosine, sphinganine, sphingosine‐1‐phosphate and ceramide) in human fibroids and pair‐matched healthy uterus tissue. We demonstrated that, in uterine leiomyomas, the contents of sphingosine, sphinganine, sphingosine‐1‐phosphate and ceramide remains quite constant. However, a trend towards elevation of ceramide and simultaneous reduction of sphingosine‐1 phosphate levels was also noticed. Additionally, in uterine leiomyomas we found relevant activation of both PTEN and MAPK(ERK1/2) signaling pathways with only a minor change in AKT activity and relatively absent HIF‐1α/AMPK activation. In conclusion, rather modest changes in sphingolipids are correlated with the activation of PTEN and MAPK(ERK1/2) signaling proteins in human uterine leiomyomas.
The odd-parity input problem in metrical stress theory
Authors: Hyde Brett
Published: December 2012

Under the weak layering approach to prosodic structure (Itô & Mester 1992), the requirement that output forms be exhaustively parsed into binary feet, even when the input contains an odd-number of syllables, results in the odd-parity input problem, which consists of two sub-problems. The odd heavy problem is a pathological type of quantity-sensitivity where a single odd-numbered heavy syllable in an odd-parity output is parsed as a monosyllabic foot. The even output problem is the systematic conversion of odd-parity inputs to even-parity outputs. The article examines the typology of binary stress patterns predicted by two approaches, symmetrical alignment (McCarthy & Prince 1993) and iterative foot optimisation (Pruitt 2008, 2010), to demonstrate that the odd-parity input problem is pervasive in weak layering accounts. It then demonstrates that the odd-parity input problem can be avoided altogether under the alternative structural assumptions of weak bracketing (Hyde 2002).
A diachronic account of phonological unnaturalness
Authors: Stausland Johnsen Sverre
Published: December 2012

Norwegian retroflexion exhibits some phonetic properties that do not seem to ‘make sense’. In Standard East Norwegian, an alveolar /ɾ/ causes a following alveolar coronal to become postalveolar, and in the Frogner and Arendal dialects of Norwegian, the same postalveolarisation process is triggered by a uvular /ʁ/. Comparative analyses of Norwegian dialects reveal that these properties are the results of historical changes and phonological diffusion across dialects. Theories attempting to analyse Norwegian retroflexion as phonetically ‘natural’ can neither fully account for these properties of Norwegian retroflexion nor capture the typological generalisations found across Norwegian dialects.
The Unwritten Constitution of the United Kingdom
Authors: Baker John
Published: December 2012

There has been much talk of constitutional reform in recent years, but the changes that have actually been taking place have often differed markedly from those that the Government has professed to espouse and have shaken the foundations of the previous system without following any coherent overall plan. Written constitutions are not without shortcomings; the conventions that held the old British constitution in place are in any case difficult to codify or enforce. But a pressing problem with an unwritten constitution is that there is no special mechanism for constitutional change. Recent reforms have therefore become associated with short-term political expediency and spin. The cure is not simple.1

As a tribute to Professor Sir John Baker QC, who has served as a member of the Editorial Board since the Ecclesiastical Law Journal's foundation and energetically continues to do so,2 I am pleased to reproduce the lightly edited text of his British Academy Maccabbaean Lecture.3 Delivered in 2009, though still topical today, it provides a cautionary critique of the direction of travel in the evolution of the United Kingdom's unwritten constitution which I hope will serve as a prelude to an occasional series of articles and comment in the pages of this Journal considering the role of the spiritual within the constitution and the established nature of the Church of England in the twenty-first century. Matters that have been ignored or marginalised in the recent constitutional revolution include the role of the Prime Minister in the appointment of bishops and archbishops and the ecclesiastical patronage exercised by the Lord Chancellor. [Editor]
Recent Legal Developments in Germany: Infant Circumcision and Church Tax
Authors: Robbers Gerhard
Published: December 2012

During the course of 2012 two significant developments occurred in Germany that are of wider interest for those who study law and religion internationally. This brief note draws attention to a decision from Cologne that was probably wrongly decided, the effect of which will be reversed by amended legislation, and to a directive from the Catholic Bishops' Conference concerning the excommunication of those Catholics who decline to pay their church tax.
Parliamentary Report
Authors: Cranmer Frank
Published: December 2012

After the Administrative Court (Toulson LJ, Royce and Macur JJ) had rejected the applications of the late Mr Tony Nicklinson and an anonymous claimant, AM, to allow doctors to end their lives without fear of prosecution, The Times reported that Anna Soubry, Conservative MP for Broxtowe and a newly appointed minister at the Department of Health, was supporting ‘the right to kill yourself’. She was subsequently supported in turn by her Liberal Democrat ministerial colleague Norman Lamb, who told the BBC that, though the issue was one for the individual's conscience and there was no Government policy on it, there was a case for looking at reform. The Ministry of Justice subsequently let it be known that there were no plans to change the existing law.
General Synod of the Church of England
Authors: Slack Stephen
Published: December 2012

The most significant legislative business considered by the Synod in 2012 was again that relating to the consecration of women to the episcopate.
General Assembly of the Church of Scotland
Authors: Cranmer Frank
Published: December 2012

General Assemblies normally address a wide range of issues and the Assembly of 2012 was no exception. On 23 May the Archbishop of Canterbury addressed the General Assembly on the challenges facing both the Church of Scotland and his own Church – and on how they might respond.
Governing Body of the Church in Wales
Authors: Morris Philip
Published: December 2012

As always, the 2012 meetings of the Governing Body addressed issues of relevance both to wider society in Wales and to the domestic life of the Church. The Archbishop's Presidential Address to the April meeting focused on the likelihood of the extension of civil marriage to same-sex partners and the issues raised by Equal Civil Marriage: a consultation. If the legislation to allow same-sex civil marriage were passed, said the Archbishop, ‘I cannot see how we, as a Church, will be able to ignore the legality of the status of such partnerships and we ought not to want to do so’. In September, on the other hand, he concentrated on what he described as ‘musings on the underlying philosophy of The Church in Wales Review Report’ and, in particular, on what the Report had to say about the Gospel and the Church as an institution.
Psychological impact of working with patients with cystic fibrosis at end-of-life, pre-transplant stage
Authors: Clisby Nicola , Shaw Samantha , Cormack Maggie
Published: December 2012

Objective:

Multidisciplinary staff who work with end-of-life, pre-transplant patients with cystic fibrosis (CF) have to juggle two seemingly opposing care approaches; active care to maintain their patients’ health and condition in anticipation of a transplant, and sensitive palliative care that takes their end-of-life wishes into consideration should they not receive a transplant. Little is known about the psychological impact on staff working within this care dichotomy. The aim of this study is to explore staff's experiences and understand more about the psychological impact of this work on them professionally and personally, and how this affects their ability to provide appropriate care for their patients.

Method:

A qualitative explorative research design was used. Ten semistructured interviews with multidisciplinary staff working in cystic fibrosis centers and units across the United Kingdom were analyzed using interpretative phenomenological analysis (IPA).

Results:

Two superordinate themes emerged from the analysis: factors contributing to the “juggle” of active and palliative care, and extent of emotional impact on staff.

Significance of results:

The study indicates that there is an emotional impact on staff working with patients with CF at end-of-life, pre-transplant stages. Specifically, it reveals the extent of the unpredictability that staff work with, and the range of emotions that staff experience, including uncertainty about professional identity and anxiety about working practices. The depth and intimacy of professional–patient relationships is highlighted, particularly for staff in close contact with and similar in age to their patients. Additionally, the strength of staff's commitment and desire to care for patients within broader humanistic terms that mesh with their own personal values is brought to light. Despite the difficulties with their work, the majority of staff adopted numerous coping strategies to manage their emotions, many of which emphasized the link between their professional and personal values in undertaking their roles.
Die Bedeutung von Berufserfahrung für den Zusammenhang zwischen Alter, entwicklungsbezogener Selbstwirksamkeit und Anpassung an organisationale Veränderungen
Authors: Molter Beate , Noefer Katrin , Stegmaier Ralf , Sonntag Karlheinz
Published: December 2012

Die vorliegende Studie untersucht den Zusammenhang zwischen Alter und adaptiver Leistung und zugrunde liegende Mechanismen. Als bedeutsam für den Zusammenhang werden die Variablen Berufserfahrung sowie das anpassungsrelevante Personmerkmal entwicklungsbezogene Selbstwirksamkeit berücksichtigt. Als adaptive Leistung werden Lernen neuer Technologien, Arbeitsaufgaben und Prozeduren, Umgang mit unsicheren/unvorhersehbaren Arbeitssituationen und interpersonelle Anpassung erfasst. Auf Basis der Theorie der Self-efficacy ( Bandura, 1977 ) wird ein Modell überprüft, bei dem Berufserfahrung den negativen Zusammenhang zwischen Alter und entwicklungsbezogener Selbstwirksamkeit zumindest teilweise mediiert und sich negativ auf adaptive Leistungen auswirkt. 858 Arbeitnehmer zwischen 18 und 65 Jahren aus unterschiedlichen Unternehmen und Branchen nahmen an der Fragebogenstudie teil. Mittels der Berechnung von Strukturgleichungsmodellen können signifikant negative indirekte Effekte von Alter über Berufserfahrung auf entwicklungsbezogene Selbstwirksamkeit nachgewiesen werden. Weiterhin lassen sich signifikant negative indirekte Effekte von Berufserfahrung auf die drei Dimensionen adaptiver Leistung über entwicklungsbezogene Selbstwirksamkeit zeigen.
ERP Responses to Facial Affect and Temperament Types in Eysenckian and Strelauvian Theories
Authors: Fajkowska Małgorzata , Zagórska Anna , Strelau Jan , Jaśkowski Piotr
Published: December 2012

Eysenck’s PEN and Strelau’s RTT theories are considered interrelated on the level of traits and translatable on the level of four ancient temperament types. However, they refer to different ways of regulation stimulation, by content (emotional and social) and by the formal (energetic and temporal) characteristics of activity, respectively. Thus, by indexing behavioral and cortical patterns of response, it was predicted that PEN- and RTT-relevant pairs of temperaments would be associated with specific attentional mechanisms. One week after administration of the FCB-TI and EPQ-R, subjects (260) performed the Emotional Go/No Go task while a 32-channel EEG was being recorded. They were instructed to respond to threatening, sad, or friendly faces, respectively, but not to any other facial expression. A range of ERP components responsive to facial stimuli were investigated. According to behavioral and cortical patterns of response, it was shown that PEN- and RTT-related pairs of temperament types were connected with effective functioning of the anterior and posterior attentional system, respectively. On the behavioral level, significant differences in attentional processing of facial affect were registered in PEN sanguines versus RTT sanguines and PEN melancholics versus RTT melancholics, while on the cortical level significant differences were registered in PEN melancholics versus RTT melancholics and PEN phlegmatics versus RTT phlegmatics. Given these results, the theoretical relations between the PEN and RTT – with particular respect to cognitive and cortical mechanisms underlying temperament types – are discussed.
Airborne observations of aerosol extinction by in situ and remote‐sensing techniques: Evaluation of particle hygroscopicity
Authors: Ziemba Luke D. , Lee Thornhill K. , Ferrare Rich , Barrick John , Beyersdorf Andreas J. , Chen Gao , Crumeyrolle Suzanne N. , Hair John , Hostetler Chris , Hudgins Charlie , Obland Michael , Rogers Raymond , Scarino Amy Jo , Winstead Edward L. , Anderson Bruce E.
Published: December 2012

Extensive profiling of aerosol optical, chemical, and microphysical properties was performed in the Washington DC/Baltimore MD region in July 2011 during NASA DISCOVER‐AQ. In situ extinction coefficient (σext,in‐situ) measurements were made aboard the NASA P3‐B aircraft coincident with remote‐sensing observations by the High‐Spectral Resolution Lidar (HSRL; σext,HSRL) aboard the NASA UC‐12 aircraft. A statistical comparison revealed good agreement within instrumental uncertainty (σext,in‐situ = 1.1 σext,HSRL − 3.2 Mm−1, r2 = 0.88) and demonstrated the robust nature of hygroscopicity measurements (f(RH)) necessary to correct observations at dry relative humidity (RH) to ambient conditions. The average liquid‐water contribution to ambient visible‐light extinction was as much as 43% in this urban region. f(RH) values were observed to vary significantly from 1.1 to 2.1 on a day‐to‐day basis suggesting influence from both local and transported sources. Results emphasize the importance of accounting for the RH dependence of optical‐ and mass‐based aerosol air‐quality measurements (e.g., of PM2.5), especially in relation to satellite and remote‐sensing retrievals.
Impact of cold O+ ions on the generation and evolution of EMIC waves
Authors: Omidi N. , Bortnik J. , Thorne R. , Chen L.
Published: December 2012

We explore the effect of cool O+ ions (~11 eV) on the generation and nonlinear evolution of electromagnetic ion cyclotron (EMIC) waves in the magnetosphere, using hybrid (kinetic ions, fluid electrons) simulations with a dipolar magnetic field. The instability is driven by the temperature anisotropy of the hot (keV), ring current protons whose density is a few percent of the background plasma consisting of cold (eV) protons and O+ ions with concentrations varying between 0 and 30% of the cold protons. The results show that for O+ ion concentration of 7% or less, the properties of the EMIC waves are similar to those in the absence of O+ ions where waves are generated at low latitudes and propagate all the way to the ionospheric boundary. Further increases in O+ density (~15%) result in waves being confined in latitude due to processes explored in this paper. At O+ densities of 30% and higher, the growth of EMIC waves is weak or non‐existent due to cyclotron resonant damping by the O+ ions. Comparing the results of the runs with no and 15% O+ ions shows that the propagation properties of the EMIC waves change dramatically in the presence of O+ ions. Specifically, they show that waves are propagating parallel and anti‐parallel to the magnetic field in both hemispheres due to reflection at points that move to higher latitudes with time. This in turn results in the nonlinear generation of field aligned electrostatic waves with large perturbations in the density of the cold protons and O+ ions and also local heating of these ions. Examination of the wave properties also shows that EMIC waves are only present in regions of space where the density of the hot protons is larger than 1% of the background level. In other words, the propagation properties of the EMIC waves are controlled by the density of the hot protons. This finding is further confirmed by performing a test hybrid simulation in which hot protons reaching latitude of 22° are removed from the run resulting in the confinement of the waves to this and lower latitudes.
Modeling the wave normal distribution of chorus waves
Authors: Chen Lunjin , Thorne Richard M. , Li Wen , Bortnik Jacob
Published: December 2012

The propagation and attenuation characteristics of lower band and upper band chorus waves are investigated by ray tracing, and the evaluation of Landau damping based on an empirical suprathermal electron model derived from Time History of Events and Macroscale Interactions during Substorms (THEMIS) data. The rate of Landau damping is found to increase at larger L‐shell, for more oblique wave normal angles, and for higher geomagnetic activity. Damping is also larger on the nightside than on the dayside and is more pronounced in the upper band than in the lower band. These features can account for the statistical pattern of chorus waves observed away from the equatorial source region. A physical model of the wave normal angle distribution along a field line is presented, which provides insight on how the wave normal angle distribution varies as chorus waves propagate away from the equatorial source region. Our modeling shows that wave emissions at low latitudes (λ ≲ 30°) come predominately from the equatorial source at the same L‐shell and that their wave normal angles increase with increasing latitude due to wave refraction caused by magnetic gradients and curvature. However, at high latitudes (λ ≳ 30°), the wave normal angle distribution along a particular field line is affected by chorus waves that arrive from an equatorial source at lower L because of significant cross‐L propagation. As a consequence, the lower band wave normal angle tends to decrease with increasing latitudes, while the upper band wave normal angle can either increase or decrease depending on the equatorial source at lower L. The effect of cross‐L propagation might also explain why observed wave normal angle distribution tends to become more field‐aligned at high latitudes. Interestingly, the upper band chorus at such high latitudes originates from lower band waves originating near the equator at lower L. A global model of wave normal variation along a field line constructed in this study is not currently available from observations but is nonetheless critically important for evaluating bounce‐averaged diffusion coefficients for future radiation belt modeling.
Hydrous minerals on Mars as seen by the CRISM and OMEGA imaging spectrometers: Updated global view
Authors: Carter J. , Poulet F. , Bibring J.‐P. , Mangold N. , Murchie S.
Published: December 2012

The surface of Mars has preserved the record of early environments in which its basaltic crust was altered by liquid water. These aqueous environments have survived in the form of hydrological morphologies and alteration minerals, including clays and hydrated salts. Because these minerals probe on Earth aqueous environments compatible with biotic activity, understanding their formation processes on Mars is of great exobiological relevance and also offers insight into Earth's now erased ancient water environments. Using remote sensing, we conducted a large‐scale investigation of the distribution, composition, age, and geomorphic settings of hydrous minerals on Mars, providing a sharpened global view of the early aqueous environments and their evolution with time. Aqueous alteration seems to have produced clays on a planetary scale but these are found to be restricted to the oldest observable terrains on Mars (∼4 Gyr). However, very diverse aqueous environments have also been found which suggest widespread, complex aqueous settings from the surface to kilometric depths, and spanning over 1 Gyr. By building a robust statistical sample of detections, the global trends inferred here attempt to provide a broad view of our current understanding of hydrous minerals on Mars and provide context for more localized, in‐depth analyses. Collectively, these trends suggest that at least transient conditions have existed on Mars which may have been favorable for pre‐biotic to biotic activity.
Sediment microbial communities in Great Boiling Spring are controlled by temperature and distinct from water communities
Authors: Cole Jessica K , Peacock Joseph P , Dodsworth Jeremy A , Williams Amanda J , Thompson Daniel B , Dong Hailiang , Wu Geng , Hedlund Brian P
Published: December 2012

Great Boiling Spring is a large, circumneutral, geothermal spring in the US Great Basin. Twelve samples were collected from water and four different sediment sites on four different dates. Microbial community composition and diversity were assessed by PCR amplification of a portion of the small subunit rRNA gene using a universal primer set followed by pyrosequencing of the V8 region. Analysis of 164 178 quality-filtered pyrotags clearly distinguished sediment and water microbial communities. Water communities were extremely uneven and dominated by the bacterium Thermocrinis. Sediment microbial communities grouped according to temperature and sampling location, with a strong, negative, linear relationship between temperature and richness at all taxonomic levels. Two sediment locations, Site A (87–80 °C) and Site B (79 °C), were predominantly composed of single phylotypes of the bacterial lineage GAL35 (p̄=36.1%), Aeropyrum (p̄=16.6%), the archaeal lineage pSL4 (p̄=15.9%), the archaeal lineage NAG1 (p̄=10.6%) and Thermocrinis (p̄=7.6%). The ammonia-oxidizing archaeon ‘Candidatus Nitrosocaldus’ was relatively abundant in all sediment samples <82 °C (p̄=9.51%), delineating the upper temperature limit for chemolithotrophic ammonia oxidation in this spring. This study underscores the distinctness of water and sediment communities in GBS and the importance of temperature in driving microbial diversity, composition and, ultimately, the functioning of biogeochemical cycles.
Advanced Thomson scattering system for high-flux linear plasma generator
Authors: van der Meiden H. J. , Lof A. R. , van den Berg M. A. , Brons S. , Donné A. J. H. , van Eck H. J. N. , Koelman P. M. J. , Koppers W. R. , Kruijt O. G. , Naumenko N. N. , Oyevaar T. , Prins P. R. , Rapp J. , Scholten J. , Schram D. C. , Smeets P. H. M. , van der Star G. , Tugarinov S. N. , Zeijlmans van Emmichoven P. A.
Published: December 2012

An advanced Thomson scattering system has been built for a linear plasma generator for plasma surface interaction studies. The Thomson scattering system is based on a Nd:YAG laser operating at the second harmonic and a detection branch featuring a high etendue (f /3) transmission grating spectrometer equipped with an intensified charged coupled device camera. The system is able to measure electron density (ne) and temperature (Te) profiles close to the output of the plasma source and, at a distance of 1.25 m, just in front of a target. The detection system enables to measure 50 spatial channels of about 2 mm each, along a laser chord of 95 mm. By summing a total of 30 laser pulses (0.6 J, 10 Hz), an observational error of 3% in ne and 6% in Te (at ne = 9.4 × 1018 m−3) can be obtained. Single pulse Thomson scattering measurements can be performed with the same accuracy for ne > 2.8 × 1020 m−3. The minimum measurable density and temperature are ne < 1 × 1017 m−3 and Te < 0.07 eV, respectively. In addition, using the Rayleigh peak, superimposed on the Thomson scattered spectrum, the neutral density (n0) of the plasma can be measured with an accuracy of 25% (at n0 = 1 × 1020 m−3). In this report, the performance of the Thomson scattering system will be shown along with unprecedented accurate Thomson-Rayleigh scattering measurements on a low-temperature argon plasma expansion into a low-pressure background.
Ferromagnetism, hysteresis and enhanced heat dissipation in assemblies of superparamagnetic nanoparticles
Authors: Singh Vanchna , Banerjee Varsha
Published: December 2012

In this paper, we develop theoretical frameworks to explain the emergence of ferromagnetism in suspensions and agglomerates of superparamagnetic (SPM) nanoparticles. In the limit of strong anisotropy, the super moments can be treated as a collection of two-state Ising spins. When adequate in number, they interact via dipole-dipole coupling to produce a dipolar field and subsequently a permanent dipole moment. As a result, this effectual ferromagnet exhibits hysteresis on the application of an oscillating magnetic field yielding heat dissipation that is several orders of magnitude larger than in a paramagnet. Using our frameworks, we provide a design for a magnetite-blood suspension that yields heat dissipation in the mW range. Its important physical application is in remedial procedures for destroying tumor and cancer cells. We are also able to explain many experiments reporting manifestations of ferromagnetism in the form of hysteresis loops, return point memory and large heat dissipation in suspensions and aggregates of SPM nanoparticles. Our frameworks can be used to manipulate heat dissipation in variety of combinations of particles and their embedding mediums. They impart a basis to the often used ad-hoc methodologies in this subject.
Effect of near atmospheric pressure nitrogen plasma treatment on Pt/ZnO interface
Authors: Nagata Takahiro , Yamashita Yoshiyuki , Yoshikawa Hideki , Uehara Tsuyoshi , Haemori Masamitsu , Kobayashi Keisuke , Chikyow Toyohiro
Published: December 2012

The effect of near atmospheric pressure nitrogen plasma (NAP) treatment of platinum (Pt)/zinc oxide (ZnO) interface was investigated. NAP can nitride the ZnO surface at even room temperature. Hard x-ray photoelectron spectroscopy revealed that NAP treatment reduced the surface electron accumulation at the ZnO surface and inhibited the Zn diffusion into the Pt electrode, which are critical issues affecting the Schottky barrier height and the ideality factor of the Pt/ZnO structure. After NAP treatment, the Pt Schottky contact indicated an improvement of electrical properties. NAP treatment is effective for the surface passivation and the Schottky contact formation of ZnO.
Compressible spherical dipolar glass model of relaxor ferroelectrics
Authors: Pirc R. , Kutnjak Z. , Novak N.
Published: December 2012

The interactions between the dielectric polarization and the fluctuations of the strain (stress) tensor in relaxor ferroelectrics are shown to give rise to the anisotropy of the anharmonic P4-term in the Landau-type free energy; however, the harmonic P2-term is still properly described by the rigid spherical random bond–random field model. These are the essential features of the compressible spherical dipolar glass model, which is used to calculate the singularities of the specific heat near field-induced critical points. The results agree with recent high-resolution calorimetric experiments in PMN [110].
Studying periodic nanostructures by probing the in-sample optical far-field using coherent phonons
Authors: Brüggemann C. , Jäger J. , Glavin B. A. , Belotelov V. I. , Akimov I. A. , Kasture S. , Gopal A. V. , Vengurlekar A. S. , Yakovlev D. R. , Akimov A. V. , Bayer M.
Published: December 2012

Optical femtosecond laser pulses diffracted into a crystalline substrate by a gold grating on top interact with gigahertz coherent phonons propagating towards the grating from the opposite side. As a result, Brillouin oscillations are detected for diffracted light. The experiment and theoretical analysis show that the amplitude of the oscillations for the first order diffracted light exceeds that of the zero order signal by more than ten times. The results provide a method for internal probing of the optical far-field inside materials containing periodic nanostructures.
Analysis of micro-Raman spectra combined with electromagnetic simulation and stress simulation for local stress distribution in Si devices
Authors: Tada Tetsuya , Poborchii Vladimir , Kanayama Toshihiko
Published: December 2012

We have developed a Raman simulation method using a finite-difference time-domain electromagnetic simulation and a finite element method stress simulation for precise local stress analysis of Si devices. This method accounts for the modification of light distribution by the sample structure, which significantly affects the Raman spectra near a metal gate structure with high refractive index and extinction coefficient. The precise stress estimation by this method is verified by analyzing polarized UV Raman measurements of a metal-oxide semiconductor field-effect transistor structure with a metal gate.