bluuebunny/crossref_metadata_2025 huggingface dataset:
Exercise and immune function: effect of ageing and nutrition
Authors: Pedersen Bente Klarlund , Bruunsgaard Helle , Jensen Marianne , Krzywkowski Karen , Ostrowski Kenneth
Published: February 2011

Strenuous exercise is followed by lymphopenia, neutrophilia, impaired natural immunity, decreased lymphocyte proliferative responses to mitogens, a low level of secretory immunoglobulin A in saliva, but high circulating levels of pro- and anti-inflammatory cytokines. These exercise-induced immune changes may provide the physiological basis of altered resistance to infections. The mechanisms underlying exercise-induced immune changes are multifactorial and include neuroendocrinological and metabolic mechanisms. Nutritional supplementation with glutamine abolishes the exercise-induced decline in plasma glutamine, but does not influence post-exercise immune impairment. However, carbohydrate loading diminishes most exercise effects of cytokines, lymphocyte and neutrophils. The diminished neutrophilia and elastase (EC3.4.21.37) responses to eccentric exercise in elderly subjects were enhanced to levels comparable with those of young subjects by fish oil or vitamin E supplements. However, although vitamin C supplementation may diminish the risk of contracting an infection after strenuous exercise, it is not obvious that this effect is linked to an effect of vitamin C on exercise-induced immune changes. In conclusion, it is premature to make recommendations regarding nutritional supplementation to avoid post-exercise impairment of the immune system.
Diversity in the 18S SSU rRNA V4 hyper-variable region ofTheileriaspp. in Cape buffalo (Syncerus caffer) and cattle from southern Africa
Authors: MANS BEN J. , PIENAAR RONEL , LATIF ABDALLA A. , POTGIETER FRED T.
Published: February 2011

Sequence variation within the 18S SSU rRNA V4 hyper-variable region can affect the accuracy of real-time hybridization probe-based diagnostics for the detection ofTheileriaspp. infections. This is relevant for assays that use non-specific primers, such as the real-time hybridization assay forT. parva(Sibekoet al.2008). To assess the effect of sequence variation on this test, theTheileria18S gene from 62 buffalo and 49 cattle samples was cloned and ∼1000 clones sequenced. Twenty-six genotypes were detected which included known and novel genotypes for theT. buffeli, T. mutans, T. taurotragiandT. veliferaclades. A novel genotype related toT.sp. (sable) was also detected in 1 bovine sample.Theileriagenotypic diversity was higher in buffalo compared to cattle. Polymorphism within theT. parvahyper-variable region was confirmed by aberrant real-time melting peaks and supported by sequencing of the S5 ribosomal gene. Analysis of the S5 gene suggests that this gene can be a marker for species differentiation.T. parva, T.sp. (buffalo) andT.sp. (bougasvlei) remain the only genotypes amplified by the primer set of the hybridization assay. Therefore, the 18S sequence diversity observed does not seem to affect the current real-time hybridization assay forT. parva.
Trajectory tracking compensation for teleoperation with transmission delays
Authors: Hu Lingyan , Liu Xiaoping P. , Liu Guoping , Xu Shaoping
Published: February 2011

The proper transmission of wave variables rather than power variables in teleoperation with time delays ensures system passivity – rendering the entire system stable, but the introduction of wave variables leads to distortion between the velocities/positions of the master and slave, and the performance deteriorates significantly with the increase of time delays. This paper presents a new compensating scheme implemented at the slave side to remove or cancel partially the distortion. The system passivity can still be maintained by tuning a properly designed low-pass filter. Compared with previous work, the main contribution of this work exists in two points: first, it is the actual velocity/trajectory of the slave rather than the reference velocity/trajectory of the slave that tracks the master one, so the quality of tracking is better and converges faster; second, the proposed compensator does not require any additional signal from the master side, minimizing the amount of data transmitted over the channel, which is very important from the practical point of view. The simulation and experiment results show that the velocity (or trajectory) tracking is significantly improved under the condition of stability, and the force presented to the user is close to the environment one, meaning a high degree of system transparency is achieved.
Inter-island dispersal of flightlessBothrometopus huntleyi(Coleoptera: Curculionidae) from the sub-Antarctic Prince Edward Island archipelago
Authors: Grobler G.C. , Bastos A.D.S. , Chimimba C.T. , Chown S.L.
Published: February 2011

Bothrometopus huntleyiis a flightless weevil endemic to the volcanically-formed sub-Antarctic Prince Edward Islands archipelago that arose approximately 0.5 million years ago (m.y.a.). Since emergence, a series of volcanic and glaciation events have occurred on Marion Island, whilst Prince Edward Island, the second island constituting the archipelago, has remained largely unaffected by glaciation. Cytochrome oxidase I gene analyses indicate that major historical dispersal events in this species are linked to the geologically discrete histories of these islands and underlie the high haplotype diversity (0.995) recovered for the Prince Edward Islands archipelago. The estimated time to haplotype coalescence of ∼ 0.723 m.y.a. is in keeping with estimated dates of island emergence, and the majority of individuals appear to have descended from a relict, high-altitude population that is still present on Marion Island. The first major inter-island dispersal event occurred ∼ 0.507 m.y.a., coinciding with the oldest dated rocks on Marion Island. Apart from this early inter-island colonization, only one other between-island dispersal event was detected. The genetically discreteB. huntleyicomplexes on each of the islands of the Prince Edward Islands archipelago together with the low levels of inter-island gene flow reaffirm the need to control alien invasive mice, which are restricted to Marion Island, and which prey on this weevil species.
Protein-losing enteropathy: integrating a new disease paradigm into recommendations for prevention and treatment
Authors: Meadows Jeffery , Jenkins Kathy
Published: February 2011

Protein-losing enteropathy is a relatively uncommon complication of Fontan procedures for palliation of complex congenital cardiac disease. However, the relative infrequency of protein-losing enteropathy belies the tremendous medical, psychosocial and financial burdens it places upon afflicted patients, their families and the healthcare system that supports them. Unfortunately, because of the complexity and rarity of this disease process, the pathogenesis and pathophysiology of protein-losing enteropathy remain poorly understood, and attempts at treatment seldom yield long-term success. The most comprehensive analyses of protein-losing enteropathy in this patient population are now over a decade old, and re-evaluation of the prevalence and progress in treatment of this disease is needed. This report describes a single institution experience with the evaluation, management, and treatment of protein-losing enteropathy in patients with congenital cardiac disease in the current era, follows with a comprehensive review of protein-losing enteropathy, focused upon what is known and not known about the pathophysiology of protein-losing enteropathy in this patient population, and concludes with suggestions for prevention and treatment.
Neuropsychological Comparison of Children with Heavy Prenatal Alcohol Exposure and an IQ-Matched Comparison Group
Authors: Vaurio Linnea , Riley Edward P. , Mattson Sarah N.
Published: February 2011

An objective in current research on children with fetal alcohol spectrum disorders (FASD) is to determine neurobehavioral profiles to identify affected individuals. Deficits observed when children with FASD are compared to typically developing controls may be confounded by lower IQ scores in the subjects with FASD. To determine if prenatal alcohol exposure is associated with neurobehavioral deficits after controlling for IQ differences, multivariate analyses were conducted to compare alcohol-exposed (ALC) subjects to a comparison group closely matched on IQ (IQC). The initial analysis included a broad neuropsychological battery with measures of language, executive function, visual–motor integration, motor ability, and academic achievement. Additional, in depth comparisons focused on visual sustained attention, verbal learning and memory and parent/guardian-reported behavior problems. Group differences (ALC < IQC) were found on verbal learning and parent-rated behavior problems. Group differences were marginally significant (measures within the broad neuropsychological comparison) or not significant (visual attention, retention of verbal material) on the remaining comparisons. Therefore, some deficits (e.g., verbal learning and behavior problems) in children with heavy prenatal alcohol exposure cannot be explained by the lower FSIQ observed in the population. These areas of relative weakness could be useful in distinguishing children with FASD from other children with lowered IQ. (JINS, 2011, 17, 463–473)
The Visual Sound-Shapes of Spectromorphology: an illustrative guide to composition
Authors: Blackburn Manuella
Published: February 2011

Since its conception, Denis Smalley's spectromorphology has equipped listeners and practitioners of electroacoustic music with appropriate and relevant vocabulary to describe the sound-shapes, sensations and evocations associated with experiences of acousmatic sound. This liberation has facilitated and permitted much-needed discussion about sound events, structures and other significant sonic detail. More than 20 years on, it is safe to assume that within the electroacoustic music community there is an agreed and collective understanding of spectromorphological vocabulary and its descriptive application. Spectromorphology's influence has been far reaching, inciting approaches to electroacoustic music analysis (Thoresen 2007), notation (Patton 2007), composition and education through its flexible functionality and accessible pool of vocabulary.
Music Composition as an Act of Cognition: ENACTIV – interactive multi-modal composing system
Authors: Spasov Miroslav
Published: February 2011

ENACTIV is a project that addresses, explores and offers solutions for converting a performer/composer's expressive sonic and kinetic patterns into continuous variables for driving sound synthesis and processing in real-time interactive composition. The investigation is inspired by the achievements in cognitive science, in particular Umberto Maturana and Francisco Varela's Santiago Theory (1980, 1987), in which the authors explain how the process of cognition arises through ‘structural coupling’ – a mutual influence among living beings, and living beings (humans in particular) and the environment, and how this process stipulates certain patterns of organisation driving the individual's behaviour.

The project investigates how a composer/performer's cognitive archetypes, which have been developed via his or her ‘structural coupling’ with the social and natural environment and expressed through voice and unwitting hand gestures, can be associated with or ‘mapped’ onto sound synthesis and processing parameters in such a way that the system will play an active role and act reciprocally, involving a certain degree of variation and unpredictability at its output. The aim of the project is to develop a creative tool which will allow professional musicians, multi-media artists and non-expert participants to engage with multi-modal improvisation in an intuitive way.
Assessment of self-efficacy for caregiving: The critical role of self-care in caregiver stress and burden
Authors: Merluzzi Thomas V. , Philip Errol J. , Vachon Dominic O. , Heitzmann Carolyn A.
Published: February 2011

Objective:

Little attention has been given to assessing the importance of self-care and communication in the caregiving setting, especially caregiving for those who are terminally ill. The Caregiver Inventory (CGI), a measure of self-efficacy for caregiving that includes these two dimensions, was subjected to psychometric analyses.

Method:

One hundred and thirty-three primary caregivers completed the CGI; of those, 81 also completed the Perceived Stress Scale (PSS), Caregiver Burden Inventory (CBI), and a measure of caregiver tasks (ADLR-CG). Based on home visits, social workers also rated the caregiver tasks required (ADLR-SW). Exploratory Factor Analysis, as well as reliability and validity analyses were conducted.

Results:

Fit indices in M + I (V. 5.1) indicated a four factors solution: Managing Medical Information (α = 0.64), Caring for Care Recipient (α = 0.78), Caring for Oneself (α = 0.88), and Managing Difficult Interactions/Emotions (α = 0.76). The CGI was highly negatively related to stress (PSS, r = −0.54, p = 0.001) and burden (CBI, p = −0.37, p = 0.001); ADLR-CG was related to burden (r =  0.43, p = 0.001) but not stress. In regression and relative importance analyses, Care of Oneself and Managing Difficult Interactions/Emotions emerged as equal in terms of having the strongest and most robust negative relationships with stress and burden.

Significance of Results:

Results suggest that the CGI is a reliable and valid measure of self-efficacy for caregiving, and indicate the importance of self-efficacy for self-care and for managing difficult communication in successfully navigating the demands of caregiving for terminally ill persons.
Prevalence of depression among relatives of cancer patients in Jordan: A cross-sectional survey
Authors: Mhaidat Nizar M. , Ai-Sweedan Suleiman A. , Alzoubi Karem H. , Alazzam Sayer I. , Banihani Mohammed N. , Yasin Muneer O. Bani , Massadeh Majed M
Published: February 2011

Objective:

Depression is common among chronically ill patients and their relatives. In this article, we investigated the prevalence of depression among relatives of cancer patients in Jordan, and studied the relation between several socio-demographic, disease- and treatment-related factors, together with the occurrence of depression among those relatives.

Method:

A cross-sectional survey study was conducted at a major university hospital in Jordan. Relatives of cancer patients were interviewed for socio-demographic information, and medical records were checked for information about disease and treatment of patient. Psychological status of the relative was assessed using the Hospital Anxiety & Depression Scale (HADS).

Results:

The prevalence of depression in our sample was 81.9%. Age and degree of relatedness were significantly correlated with the occurrence of depression among relatives of cancer patients. Significant correlations were also detected between depression among patient's relatives and the stage of the disease. Positive predictive factors for depression included relatives being middle aged, close relatedness, patients being in advanced disease stage, and on chemotherapy or undergoing surgery for cancer treatment.

Significance of results:

Depression is prevalent among relatives of cancer patients. Therefore, more attention is needed to detect changes in the psychological state of vulnerable relatives of cancer patients, in an effort to reduce the occurrence of depression.
Where do our patients die? A review of the place of death of cancer patients in Cape Town, South Africa
Authors: Manicom Clare
Published: February 2011

Objective: A 3-year review of the place of death of patients from a private oncology unit in Cape Town explores the length of time patients spent in acute care hospital beds, under the oncologist's care, prior to their death. Implications for improved staff training, patient support, and family education are identified.

Method: This is an exploratory quantitative study that captures details of place of death and particulars of length of acute care hospital stay for cancer patients of a private oncology unit. Data was gathered from 424 patient files, from January 2006 to December 2008, and is interpreted using simple descriptive statistics.

Results: Of the 424 recorded deaths, the average age at death was 66.09 years, with lung and bronchial cancer accounting for the leading diagnosis at death (23.82%). Most of patient deaths recorded (42.92%) occurred at home, with death under the oncologist's care in an acute medical ward comprising the second largest category (34.20%). The majority of the patients who died in this ward (38%) died within 3 days of admission.

Significance of results: Although medical and community support for end-of-life care at home are not uniformly available to all South Africans, the patients and families in this study had good access to hospice care, and achieved a higher “death at home” rate than that seen in several more developed countries. The review of place of death and length of hospitalization prior to death highlights the need for staff at private oncology units to be trained in and comfortable with palliative care. Attention is also drawn to the very real needs of carers and family members of patients, if death is planned to occur in the patient's home.
Factors affecting hope in a sample of fatigued breast cancer outpatients
Authors: Schjolberg Tore Kr. , Dodd Marylin , Henriksen Nils , Rustoen Tone
Published: February 2011

Objective:

The aims of this study of women with breast cancer were: to describe the levels of hope and compare hope scores for these patients with a sample from the general Norwegian population; to describe the relationship between hope and fatigue; and finally to evaluate the effect of demographic and clinical characteristics and fatigue on hope.

Method:

A total of 160 Norwegian outpatients with cancer and fatigue (>2.5 on a 0–10 scale) completed the Herth Hope Index (HHI), Fatigue Questionnaire (FQ), and Self-administered Comorbidity Questionnaire (SCQ).

Results:

The mean age of the women was 55.3 years (SD = 9.4), 81% lived with someone, and 67% were employed. The most common comorbidities were back pain (42%), osteoarthritis (26%), and headache (19%). The fatigued breast cancer patients reported significantly higher total hope scores than the general Norwegian population (p < .0001). The difference was largest in the individual item “I can see a light in the tunnel,” to which the cancer sample reported the highest scores, but they also felt more “scared about the future.” Total hope score was negatively correlated with total fatigue (TF), mental fatigue (MF), and chronic fatigue (CF), but not with physical fatigue (PF). Demographic and clinical characteristics were not significantly related to hope, except that patients who were married or living with someone showed significantly higher total hope scores.

Significance of results:

The higher levels of hope in breast cancer patients compared with the general Norwegian population may reflect a response shift in patients after getting a cancer diagnosis. The fact that a significant relationship was found between total hope scores and living arrangements may indicate that hope is easier to establish when patients have someone to relate to or receive support from. Hope and total fatigue were significantly, but weakly correlated.
Culture, institutions and economic growth
Authors: DE JONG EELKE
Published: February 2011

In his article ‘Institutions and Economic Development: Theory, Policy and History’, Ha-Joon Chang rightly argues that historical evidence does not irrefutably suggest that countries characterized by free markets perform better than those in which the state plays a much more prominent role. However, his method of substantiating his claims by means of examples from different sources and periods does not convince. A more systematic and theoretically founded approach is needed. This comment focuses on the cross-section versus time-series approach and the relation between culture, institutions and economic development.
A Trend-Change Extension of the Cairns-Blake-Dowd Model
Authors: Sweeting P. J.
Published: February 2011

This paper builds on the two-factor mortality model known as the Cairns-Blake-Dowd (CBD) model, which is used to project future mortality. It is shown that these two factors do not follow a random walk, as proposed in the original model, but that each should instead be modelled as a random fluctuation around a trend, the trend changing periodically. The paper uses statistical techniques to determine the points at which there are statistically significant changes in each trend. The frequency of change in each trend is then used to project the frequency of future changes, and the sizes of historical changes are used to project the sizes of future changes. The results are then presented as fan charts, and used to estimate the range of possible future outcomes for period life expectancies. These projections show that modelling mortality rates in this way leaves much greater uncertainty over future life expectancy in the long term.
Conditions of intergovernmental armaments cooperation in Western Europe, 1996–2006
Authors: Thiem Alrik
Published: February 2011

Defence cooperation between Western European countries has increased considerably since the end of the Cold War. An analytical distinction can be made between political and economic cooperation, the latter having been neglected by political scientists. This study advances the debate on economic cooperation by identifying sources of variation in the European Union (EU)-15 countries’ membership rate in cooperative armamentsforaaimed at restructuring the demand side of European defence from 1996 to 2006. By combining six models from three different schools of thought, the risk of confirmation bias through intra-paradigmatic reasoning is reduced. At the same time, fuzzy-set analysis opens up the space for data-driven combination effects. Two distinct combinations form sufficient paths leading to high rates of membership. Most importantly, intentions to create collective defence technological and industrial benefits combine with trust in partners’ ability and integrity to form an essential combination of conditions for governments to pursue cooperation on armaments.
Education and the Zeitgeist: government positions and public opinion on income distribution
Authors: Jakobsen Tor G.
Published: February 2011

Despite a sizable literature on the elite mass linkage, few of these studies are cross-national. In this paper, I apply multilevel ordered logit models to investigate public opinion toward redistribution in 23 European countries. I test whether these views depend on: (1) the policies of the government (i.e. the bandwagon effect) and (2) personal interest, as indicated by income and education. Briefly, the bandwagon effect appears when people’s perception of strong support for one line of thinking leads to their adopting this reasoning. The self-interest argument states that those who would benefit from a redistributive policy are likely to support it. In addition, I argue that higher education has a dual nature, consisting of an interest in providing one’s own self-interest as well as a critical thinking component. Elite opinion is quantified from the party manifestos of incumbent parties and tested against data from the European Social Survey. I find no significant direct effect of political elite views on public opinion. On the other hand, there is strong support for the self-interest argument, and yet the rightist tendency for higher educated persons is significantly smaller if their government is economically conservative. This finding is attributed to the critical thinking argument as well as to the reasoning that higher education makes people better able to filter political information, thus countering the bandwagon effect.
Devolution and EU policy-shaping: bridging the gap between multi-level governance and liberal intergovernmentalism
Authors: Tatham Michaël
Published: February 2011

This paper argues that the impact of devolution has been largely misperceived in both liberal intergovernmentalist (LI) and multi-level governance (MLG) accounts of European Union (EU) politics. To address the shortcomings of both LI and MLG, a new data set measuring institutionalized regional involvement in the domestic EU policy-shaping process in the EU-27 is presented. Analysis shows that the relationship between devolution and institutionalized regional involvement is overall positive but non-linear, with a strong threshold effect that is best captured by a quadratic function. The causal nature of the link between devolution and institutionalized regional involvement is ascertained through qualitative means using process tracing and Mill’s method of difference. The article concludes with the necessary updating of MLG and LI frameworks to account for the impact of devolution on EU policy-shaping.
Paradigm man vs. the bricoleur: bricolage as an alternative vision of agency in ideational change
Authors: Carstensen Martin B.
Published: February 2011

The status of ideational explanations in political science has been strengthened by the argument that institutionalized ideas structure actors’ identification of their interests as well as the interests of their political adversaries. Despite its utility, the focus on the institutionalization of ideas has had the unfortunate consequence that actors are often, implicitly or explicitly, believed to internalize ideas, making it difficult to understand how actors are able to change their ideas and institutions. Drawing on cultural sociology and ideational theory, the paper introduces the ‘bricoleur’ as an alternative vision of agency. It is argued, first, that actors cannot cognitively internalize highly structured symbolic systems, and ideas are thus ‘outside the minds of actors’. Second, using the cognitive schemas at their disposal, actors construct strategies of action based on pre-constructed ideational and political institutions. Third, actors must work actively and creatively with the ideas and institutions they use, because the structure within which actors work does not determine their response to new circumstances. Fourth, as a vast number of ideational studies have shown, actors face a complex array of challenges in getting their ideas to the top of the policy agenda, which makes it all the more important to act pragmatically, putting ideas together that may not be logically compatible but rather answer political and cultural logics. In sum, agency often takes the form of bricolage, where bits and pieces of the existing ideational and institutional legacy are put together in new forms leading to significant political transformation.
Global river temperatures and sensitivity to atmospheric warming and changes in river flow
Authors: van Vliet M. T. H. , Ludwig F. , Zwolsman J. J. G. , Weedon G. P. , Kabat P.
Published: February 2011

This study investigates the impact of both air temperature and river discharge changes on daily water temperatures for river stations globally. A nonlinear water temperature regression model was adapted to include discharge as a variable in addition to air temperature, and a time lag was incorporated to apply the model on a daily basis. The performance of the model was tested for a selection of study basin stations and 157 river temperature stations globally using historical series of daily river temperature, air temperature, and river discharge for the 1980–1999 period. For the study basin stations and for 87% of the global river stations, the performance of the model improved by including discharge as an input variable. Greatest improvements were found during heat wave and drought (low flow) conditions, when water temperatures are most sensitive to atmospheric influences and can reach critically high values. A sensitivity analysis showed increases in annual mean river temperatures of +1.3 °C, +2.6 °C, and +3.8 °C under air temperature increases of +2 °C, +4 °C, and +6 °C, respectively. Discharge decreases of 20% and 40% exacerbated water temperature increases by +0.3 °C and +0.8 °C on average. For several stations, maximum water temperatures on a daily basis were higher under an air temperature increase of +4 °C combined with a 40% discharge decrease compared to an air temperature increase of +6 °C (without discharge changes). Impacts of river discharge on water temperatures should therefore be incorporated to provide more accurate estimations of river temperatures during historical and future projected dry and warm periods.
How Do Oceanic Plateaus Form? Clues From Drilling at Shatsky Rise
Authors: Sager William W. , Sano Takashi , Geldmacher Jörg
Published: February 2011

Oceanic plateaus are huge basaltic constructions whose eruptions may briefly outstrip even global mid‐ocean ridge magma production. Although they form great undersea mountains, their origins are poorly understood. A widely accepted explanation is that oceanic plateaus are built by massive eruptions from the head of nascent thermal mantle plumes that rise from deep in the mantle to the surface [e.g., Duncan and Richards, 1991]. An alternative is that plateaus erupt by decompression melting of fusible patches in the upper mantle at plate edges or zones of extension [Foulger, 2007].
New Software for Plotting and Analyzing Stratigraphic Data
Authors: Lewis K. W. , Keeler T. L. , Maloof A. C.
Published: February 2011

Stratigraphy, the study of layering in rock, ice, and sediment records, lies at the heart of the geological sciences. The lithology, grain size, and texture of layered successions, along with a host of measurable geochemical and geophysical parameters, record information about past environmental and geographic conditions. Despite the importance of stratigraphic records to Earth history, there is a dearth of accessible, user‐friendly open‐source software for generating stratigraphic plots and analyzing stratigraphic data. Often, stratigraphic logs and associated geochemical and geophysical data are assembled and plotted manually using multiple software packages. The integrated stratigraphic data can then be cumbersome to analyze quantitatively.
U.S. Interior Department Issues Scientific Integrity Guidelines and Strategic Plan
Authors: Showstack Randy
Published: February 2011

U.S. Department of the Interior (DOI) issued detailed scientific integrity guidelines on 1 February, becoming the first federal agency to do so following a 9 July 2009 White House memorandum on the subject and 17 December 2010 White House guidelines for federal agencies. DOI's guidelines indicate that the department “will not tolerate loss of integrity in the performance of scientific and scholarly activities or in the application of science and scholarship in decision making.”
Internal rotation of methyl group in electronically excited o- and m-ethynyltoluene: New correlation between the Hammett substituent constant σm and rotational barrier change
Authors: Tanaka Sei-ichi , Okuyama Katsuhiko
Published: February 2011

We have determined the potential-energy function for the internal rotation of the methyl group for o- and m-ethynyltoluene in the electronic excited (S1) and ground (S0) states by measuring the fluorescence excitation and single-vibronic-level dispersed fluorescence spectra in a jet. The 0−0 bands were observed at 35 444 and 35 416 cm−1, respectively. The methyl group in o-ethynyltoluene is shown to be a rigid rotor with a potential barrier to rotation of 190 ± 10 cm−1 in both states. No change in the conformation occurred upon excitation. Barrier heights of m-ethynyltoluene in the S0 and S1 states are shown to be 19 ± 3 and 101 ± 1 cm−1, respectively. A conformational change occurred with rotation by 60º upon excitation. The potential parameters were as follows: reduced rotational constant (B) of 5.323 cm−1, centrifugal-distortion constant (D) of 6.481 × 10−5 cm−1, V3 = 19 cm−1, V6 = −6 cm−1, and V9 = 0 cm−1 in the S0 state, and B = 5.015 cm−1, D = 5.392 × 10−5 cm−1, V3 = 101 cm−1, V6 = −22 cm−1, and V9 = −2 cm−1 in the S1 state. For m-methylstyrene, m-tolunitrile, and m-ethynyltoluene, which all have a multiple-bonded carbon in the substituent, we found a new correlation between the Hammett substituent constant σm and the change in the barrier of the methyl group upon excitation.
Design, fabrication, and implementation of thermally driven outdoor testing devices for building joint sealants
Authors: White C. C. , Tan K. T. , O'Brien E. P. , Hunston D. L. , Chin J. W. , Williams R. S.
Published: February 2011

The paper describes the development, implementation, and testing of two thermally driven outdoor exposure instruments. These devices are unique in their ability to impose field generated thermally induced strain on sealant specimens while monitoring their resulting load and displacement. The instruments combine a fixed wood and steel supporting frame with a moving polyvinyl chloride frame, and employ differences in the coefficients of thermal expansion between the supporting frame and moving frame to induce strain on the sealant specimens. Two different kinds of instruments have been fabricated, “winter/tension” and “winter/compression” designs. In the winter/tension design, the thermally induced dimensional change is directly transferred to the specimens; while in the winter/compression design, the samples are loaded in an opposite direction with the dimensional change. Both designs are instrumented to monitor load and displacement and are built so that the strain on the specimen does not exceed ±25% over the range of temperatures expected in Gaithersburg, MD. Additionally, a weather station is colocated with the device to record environmental conditions in 1 min intervals. This combination of weather information with mechanical property data enables a direct link between environmental conditions and the corresponding sealant response. The reliability and effectiveness of these instruments are demonstrated with a typical sealant material. The results show that the instruments work according to the design criteria and provide a meaningful quantitative platform to monitor the mechanical response of sealant exposed to outdoor weathering
Hybrid functional investigations of band gaps and band alignments for AlN, GaN, InN, and InGaN
Authors: Moses Poul Georg , Miao Maosheng , Yan Qimin , Van de Walle Chris G.
Published: February 2011

Band gaps and band alignments for AlN, GaN, InN, and InGaN alloys are investigated using density functional theory with the with the Heyd–Scuseria–Ernzerhof {HSE06 [J. Heyd, G. E. Scuseria, and M. Ernzerhof, J. Chem. Phys. 134, 8207 (2003)10.1063/1.3548872; 124, 219906 (2006)]} XC functional. The band gap of InGaN alloys as a function of In content is calculated and a strong bowing at low In content is found, described by bowing parameters 2.29 eV at 6.25% and 1.79 eV at 12.5%, indicating the band gap cannot be described by a single composition-independent bowing parameter. Valence-band maxima (VBM) and conduction-band minima (CBM) are aligned by combining bulk calculations with surface calculations for nonpolar surfaces. The influence of surface termination [(1$\bar 1$1¯00) m-plane or (11$\bar 2$2¯0) a-plane] is thoroughly investigated. We find that for the relaxed surfaces of the binary nitrides the difference in electron affinities between m- and a-plane is less than 0.1 eV. The absolute electron affinities are found to strongly depend on the choice of XC functional. However, we find that relative alignments are less sensitive to the choice of XC functional. In particular, we find that relative alignments may be calculated based on Perdew–Becke–Ernzerhof [J. P. Perdew, K. Burke, and M. Ernzerhof, Phys. Rev. Lett. 134, 3865 (1996)] surface calculations with the HSE06 lattice parameters. For InGaN we find that the VBM is a linear function of In content and that the majority of the band-gap bowing is located in the CBM. Based on the calculated electron affinities we predict that InGaN will be suited for water splitting up to 50% In content.
On a class of n-Leibniz deformations of the simple Filippov algebras
Authors: de Azcárraga José A. , Izquierdo José M.
Published: February 2011

We study the problem of infinitesimal deformations of all real, simple, finite-dimensional Filippov (or n-Lie) algebras, considered as a class of n-Leibniz algebras characterized by having an n-bracket skewsymmetric in its n − 1 first arguments. We prove that all n > 3 simple finite-dimensional Filippov algebras (FAs) are rigid as n-Leibniz algebras of this class. This rigidity also holds for the Leibniz deformations of the semisimple n = 2 Filippov (i.e., Lie) algebras. The n = 3 simple FAs, however, admit a nontrivial one-parameter infinitesimal 3-Leibniz algebra deformation. We also show that the n ⩾ 3 simple Filippov algebras do not admit nontrivial central extensions as n-Leibniz algebras of the above class.
High-pressure x-ray diffraction study of CdMoO4 and EuMoO4
Authors: Errandonea D. , Santamaria-Perez D. , Achary S. N. , Tyagi A. K. , Gall P. , Gougeon P.
Published: February 2011

We studied the effects of high pressure on the crystalline structure of scheelite-type CdMoO4 and EuMoO4. We found that the compressibility of the materials is highly nonisotropic, with the c-axis being the most compressible one. We also observed clear evidence of a structural phase transition at 12 GPa (CdMoO4) and 8.8 GPa (EuMoO4). The high-pressure phase has a monoclinic structure similar to M-fergusonite. The transition is reversible, and no volume change is detected between the low- and high-pressure phases. The results contradict early x-ray diffraction studies carried out in CdMoO4 and are compared with those obtained previously in isomorphic molybdates. Finally, the equation of state for both compounds is also determined.
Exact averaging of laminar dispersion
Authors: Ratnakar Ram R. , Balakotaiah Vemuri
Published: February 2011

We use the Liapunov–Schmidt (LS) technique of bifurcation theory to derive a low-dimensional model for laminar dispersion of a nonreactive solute in a tube. The LS formalism leads to an exact averaged model, consisting of the governing equation for the cross-section averaged concentration, along with the initial and inlet conditions, to all orders in the transverse diffusion time. We use the averaged model to analyze the temporal evolution of the spatial moments of the solute and show that they do not have the centroid displacement or variance deficit predicted by the coarse-grained models derived by other methods. We also present a detailed analysis of the first three spatial moments for short and long times as a function of the radial Peclet number and identify three clearly defined time intervals for the evolution of the solute concentration profile. By examining the skewness in some detail, we show that the skewness increases initially, attains a maximum for time scales of the order of transverse diffusion time, and the solute concentration profile never attains the Gaussian shape at any finite time. Finally, we reason that there is a fundamental physical inconsistency in representing laminar (Taylor) dispersion phenomena using truncated averaged models in terms of a single cross-section averaged concentration and its large scale gradient. Our approach evaluates the dispersion flux using a local gradient between the dominant diffusive and convective modes. We present and analyze a truncated regularized hyperbolic model in terms of the cup-mixing concentration for the classical Taylor–Aris dispersion that has a larger domain of validity compared to the traditional parabolic model. By analyzing the temporal moments, we show that the hyperbolic model has no physical inconsistencies that are associated with the parabolic model and can describe the dispersion process to first order accuracy in the transverse diffusion time.
Quantum Monte Carlo with Jastrow-valence-bond wave functions
Authors: Braïda Benoît , Toulouse Julien , Caffarel Michel , Umrigar C. J.
Published: February 2011

We consider the use in quantum Monte Carlo calculations of two types of valence bond wave functions based on strictly localized active orbitals, namely valence bond self-consistent-field and breathing-orbital valence bond wave functions. Complemented by a Jastrow factor, these Jastrow-valence-bond wave functions are tested by computing the equilibrium well depths of the four diatomic molecules C2, N2, O2, and F2 in both variational Monte Carlo and diffusion Monte Carlo. We show that it is possible to design compact wave functions based on chemical grounds that are capable of describing both static and dynamic electron correlations. These wave functions can be systematically improved by inclusion of valence bond structures corresponding to additional bonding patterns.
The crystallinity and mechanical properties of indium tin oxide coatings on polymer substrates
Authors: Kim Eun-Hye , Yang Chan-Woo , Park Jin-Woo
Published: February 2011

We present the relationship between the microstructure and mechanical strength of indium tin oxide (ITO) on flexible substrates. With varying thickness (hf), ITO is deposited on polyethylene terephthalate (PET) by dc magnetron sputtering. The microstructure of ITO is controlled by substrate surface conditions and sputtering parameters. The maximum substrate temperature during deposition is limited to 80 °C due to the low glass transition temperature (Tg) of PET. The crystallinity and surface roughness (Rrms) are analyzed by high resolution x-ray diffraction, high resolution transmission electron microscopy, and AFM. The crack resistance of ITO is evaluated by uniaxial tension test. The experimental results reveal that, at a fixed hf, the degree and quality of crystallinity of ITO are highly improved by increasing sputtering power and the substrate temperature. As the crystallinity is improved, the ratio of preferred growth orientations of (222) to (400) is increased and the degree of peak shifts to lower 2θ is decreased. They indicate that the crystallinity is improved as the lattice damage is reduced and film density is increased. The tension test results confirm that, up to a certain hf, the strength of ITO can be significantly enhanced by improving the microstructures.
Communication: Shifted forces in molecular dynamics
Authors: Toxvaerd Søren , Dyre Jeppe C.
Published: February 2011

Simulations involving the Lennard-Jones potential usually employ a cutoff at r = 2.5σ. This communication investigates the possibility of reducing the cutoff. Two different cutoff implementations are compared, the standard shifted potential cutoff and the less commonly used shifted forces cutoff. The first has correct forces below the cutoff, whereas the shifted forces cutoff modifies Newton's equations at all distances. The latter is nevertheless superior; we find that for most purposes realistic simulations may be obtained using a shifted forces cutoff at r = 1.5σ, even though the pair force is here 30 times larger than at r = 2.5σ.
Unzipped graphene nanoribbons as sensitive O2 sensors: Electron spin resonance probing and dissociation kinetics
Authors: Rao S. S. , Stesmans A. , Keunen K. , Kosynkin D. V. , Higginbotham A. , Tour J. M.
Published: February 2011

Electron spin resonance study of unzipped graphene nanoribbons (GNRs) reveals a specific carbon-related signal, denoted GC, at g=2.0032, attributed to GNRs periphery centers. The signal is observed to be readily quenched upon O2 adsorption, which appears to be fully reversible upon room temperature vacuum treatment. Its depassivation behavior, observed from 130 K onward, is well described by first-order kinetics, characterized by the dissociation energy of 0.58±0.04 eV of spread 0.11±0.02 eV. The GC signal is not sensitive to other gases, such as H2, He, N2, and Ar, pointing to a GC–O2 physisorption interaction unique for GNRs, in agreement with theoretical insight. The GC center thus emerges as a highly selective, sensitive, and reversible O2 sensor.
Thermal rectification in bulk materials with asymmetric shape
Authors: Sawaki D. , Kobayashi W. , Moritomo Y. , Terasaki I.
Published: February 2011

We investigate thermal rectification in a bulk material with a pyramid shape to elucidate shape dependence of the thermal rectification, and find that rectifying coefficient R is 1.35 for this shape, which is smaller than R=1.43 for a rectangular shape. This result is fully duplicated by our numerical calculation based on Fourier’s law. We also apply this calculation to a given shape, and show a possible way to increase R depending on the shape.
Improvement of voltage and charge balance in inverted top-emitting organic electroluminescent diodes comprising doped transport layers by thermal annealing
Authors: Thomschke Michael , Hofmann Simone , Olthof Selina , Anderson Merve , Kleemann Hans , Schober Matthias , Lüssem Björn , Leo Karl
Published: February 2011

We present investigations of top emitting organic light emitting devices (OLED) comprising n- and p-doped organic charge transport layers. It has been found previously that in comparison to noninverted p-i-n OLEDs, inverted n-i-p OLEDs show reduced device performances after fabrication. These differences can be eliminated by subsequent thermal annealing of the whole n-i-p OLED. After this process, the n-i-p OLED exhibits a superior low driving voltage of 2.9 V at 1000 cd/m2 and shows an increase in external quantum efficiency from 11% to almost 15% which we ascribe to a modified charge balance within the intrinsic organic emission layer.
Asymmetric acoustic gratings
Authors: He Zhaojian , Peng Shasha , Ye Yangtao , Dai Zhongwei , Qiu Chunyin , Ke Manzhu , Liu Zhengyou
Published: February 2011

The unidirectional transmission of acoustic waves is realized by a simple geometrically asymmetric steel grating structure. This exotic phenomenon stems from the one-way diffraction effect induced by the different periods of the slits on the both surfaces of the sample. And the frequency range of unidirectional transmission is simply determined by the structure periods. The experimental results agree well with the theoretical simulation. This remarkable effect is expected potential applications in ultrasonic devices, such as acoustic rectifiers and acoustic diodes.
Subacute casemix classification for stroke rehabilitation in Australia. How well does AN-SNAP v2 explain variance in outcomes?
Authors: Kohler Friedbert , Renton Roger , Dickson Hugh G. , Estell John , Connolly Carol E.
Published: February 2011

Objective. We sought the best predictors for length of stay, discharge destination and functional improvement for inpatients undergoing rehabilitation following a stroke and compared these predictors against AN-SNAP v2. Method. The Oxfordshire classification subgroup, sociodemographic data and functional data were collected for patients admitted between 1997 and 2007, with a diagnosis of recent stroke. The data were factor analysed using Principal Components Analysis for categorical data (CATPCA). Categorical regression analyses was performed to determine the best predictors of length of stay, discharge destination, and functional improvement. Results. A total of 1154 patients were included in the study. Principal components analysis indicated that the data were effectively unidimensional, with length of stay being the most important component. Regression analysis demonstrated that the best predictor was the admission motor FIM score, explaining 38.9% of variance for length of stay, 37.4%.of variance for functional improvement and 16% of variance for discharge destination. Conclusion. The best explanatory variable in our inpatient rehabilitation service is the admission motor FIM. AN- SNAP v2 classification is a less effective explanatory variable. This needs to be taken into account when using AN-SNAP v2 classification for clinical or funding purposes. What is known about the topic? AN-SNAP v2, a major classification tool for inpatient rehabilitation units has been described and used in a small number of published studies. The ability to predict variance by AN-SNAP v2 has not been previously described. What does this paper add? This paper indicates that AN-SNAP v2 is not a good predictor of outcomes in patients in medical rehabilitation units, challenging its utility as a classification tool. What are the implications for practitioners? Practitioners will have a broader understanding of the strengths and weaknesses of the AN-SNAP v2 classification.