bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo ultra‐fast photoacoustic flow cytometry of circulating human melanoma cells using near‐infrared high‐pulse rate lasers
Authors: Nedosekin Dmitry A. , Sarimollaoglu Mustafa , Ye Jian‐Hui , Galanzha Ekaterina I. , Zharov Vladimir P.
Published: July 2011

The circulating tumor cells (CTCs) appear to be a marker of metastasis development, especially, for highly aggressive and epidemically growing melanoma malignancy that is often metastatic at early stages. Recently, we introduced in vivo photoacoustic (PA) flow cytometry (PAFC) for label‐free detection of mouse B16F10 CTCs in melanoma‐bearing mice using melanin as an intrinsic marker. Here, we significantly improve thespeed of PAFC by using a high‐pulse repetition rate laser operating at 820 and 1064 nm wavelengths. This platform was used in preclinical studies for label‐free PA detection of low‐pigmented human CTCs. Demonstrated label‐free PAFC detection, low level of background signals, and favorable safety standards for near‐infrared irradiation suggest that a fiber laser operating at 1064 nm at pulse repetition rates up to 0.5 MHz could be a promising source for portable clinical PAFC devices. The possible applications can include early diagnosis of melanoma at the parallel progression of primary tumor and CTCs, detection of cancer recurrence, residual disease and real‐time monitoring of therapy efficiency by counting CTCs before, during, and after therapeutic intervention. Herewith, we also address sensitivity of label‐free detection of melanoma CTCs and introduce in vivo CTC targeting by magnetic nanoparticles conjugated with specific antibody and magnetic cells enrichment. © 2011 International Society for Advancement of Cytometry
Modular anti‐EGFR and anti‐Her2 targeting of SK‐BR‐3 and BT474 breast cancer cell lines in the presence of ErbB receptor‐specific growth factors
Authors: Diermeier‐Daucher Simone , Breindl Stefanie , Buchholz Stefan , Ortmann Olaf , Brockhoff Gero
Published: July 2011

Over the last decade, a number of monoclonal antibodies and small molecule inhibitors emerged as potent therapeutic agents in the treatment of Her2/neu overexpressing breast cancer. Numerous patients, however, do not adequately respond to anti‐epidermal growth factor receptor (EGFR)/Her2 receptor targeting. Receptor‐ and, in turn, growth‐stimulating effects, which potentially hamper antiproliferative cell treatment, have barely been investigated. BT474 and SK‐BR‐3 breast cancer cell lines were treated with Trastuzumab, Pertuzumab, and Lapatinib alone using different combinations and concentrations. Moreover, epidermal growth factor (EGF) or heregulin (HRG) was added to reveal potential growth factor‐mediated compensatory effects. Receptor and intracellular signaling were analyzed as a function of cell treatment. Read‐out parameters were cell proliferation and apoptosis. BT474 cells were efficiently driven into quiescence by Trastuzumab, but not by Pertuzumab treatment. Simultaneous EGF or HRG administration, however, restored the BT474 cell proliferation capacity. In contrast, neither therapeutic antibody treatment caused a profound inhibition of SK‐BR‐3 cell‐cycle progress. Lapatinib turned out to be the most potent cell‐cycle inhibitor in both cell lines even though its impact was significantly abrogated in the presence of EGF and HRG. The compensatory effect of EGF on Lapatinib‐induced cell‐cycle inhibition was reversed by Trastuzumab as well as by Pertuzumab treatment. Most importantly, HRG‐caused compensation of Lapatinib‐induced cell‐cycle exit was reversed by Pertuzumab but not by Trastuzumab. Apparently, multiple anti‐EGFR/Her2 targeting by using Trastuzumab, Pertuzumab, and Lapatinib more efficiently affects receptor function (interaction and activation) and consequently enhances their antiproliferative capacity. Growth inhibition by anticancer drugs targeted to Her/ErbB receptors, however, can be significantly undermined in the presence of EGF and in particular by HRG treatment, which suggests that specific therapeutic growth factor sequestration might further enhance anti‐EGFR/Her2 targeting. © 2011 International Society for Advancement of Cytometry
Estimating the future decline of wild coho salmon populations resulting from early spawner die-offs in urbanizing watersheds of the Pacific Northwest, USA
Authors: Spromberg Julann A , Scholz Nathaniel L
Published: July 2011

Since the late 1990s, monitoring efforts evaluating the effectiveness of urban stream restoration projects in the greater metropolitan area of Seattle, Washington, USA, have detected high rates of premature mortality among adult coho salmon (Oncorhynchus kisutch) in restored spawning habitats. Affected animals display a consistent suite of symptoms (e.g., disorientation, lethargy, loss of equilibrium, gaping, fin splaying) that ultimately progresses to death on a timescale of a few hours. Annual rates of prespawn mortality observed over multiple years, across several drainages, have ranged from approximately 20% to 90% of the total fall run within a given watershed. Current weight-of-evidence suggests that coho prespawn mortality is caused by toxic urban stormwater runoff. To evaluate the potential consequences of current and future urbanization on wild coho salmon, we constructed life-history models to estimate the impacts of prespawn mortality on coho populations and metapopulations. At the low (20%) and high (90%) ends of the range of observed mortality, model results indicated the mean time to extinction of localized coho populations in 115 and 8 y, respectively. The presence of productive source populations (i.e., unaffected by prespawn mortality) within a metapopulation reduced local extinction risk. However, as more populations within a metapopulation become affected by spawner die-offs prior to spawning, the source population's productivity declined. These simple models demonstrate the potential for rapid losses from coho populations in urbanizing watersheds. Because the models do not account for possible impacts of toxic runoff to other coho life stages, they likely underestimate the cumulative impacts of nonpoint source pollution on wild populations. Integr Environ Assess Manag 2011;7:648–656. © 2011 SETAC
Development of a self‐report instrument to assess social and emotional development
Authors: Seal Craig R. , Beauchamp Kenneth L. , Miguel Krystal , Scott Amy N.
Published: July 2011

The authors present a revised model and a new measure of social and emotional development in higher education. They describe the psychometric properties of the measure, using a sample of 632 freshman students at a small private university. Social emotional development is defined as the enhancement of individual capacity to recognize and regulate emotional information and behaviors to facilitate desirable social outcomes. The analysis of the Social Emotional Development Inventory indicates the current instrument has an appropriate factor structure and adequate internal consistency. Recommendations for future versions of the instrument are included.
A comparative analysis of affirmative action in the United Kingdom and United States
Authors: Archibong Uduak , Sharps Phyllis W.
Published: July 2011

Based on research conducted during a large‐scale European Commission project on international perspectives on positive/affirmative action measures, the authors provide a comparative analysis of the legal context and perceptions of the impact of positive action in the United Kingdom and the United States. The study adopted participatory methods including consensus workshops, interviews, and legal analysis to obtain data from those individuals responsible for designing and implementing positive action measures. Findings are discussed, conclusions drawn, and wide‐ranging recommendations are made at governmental and organizational levels. The authors conclude by suggesting possible implications for policy and argue for widespread awareness‐raising campaigns of both the need for positive action measures for disadvantaged groups and the benefits of such measures for wider society. They also recommend the adoption of a more coherent and collaborative approach to the utilization and evaluation of the effectiveness of positive or affirmative action.
Leisure, recreation, and play from a developmental context
Authors: Caldwell Linda L. , Witt Peter A.
Published: July 2011

Personally meaningful and positive leisure pursuits are powerful mechanisms for adolescent development. Elements and characteristics of leisure experiences contribute directly to the development of identity, autonomy, competence, initiative, civic duty, and social connections.
Back to the future: The potential relationship between leisure and education
Authors: Fleming David S. , Allen Lawrence R. , Barcelona Robert J.
Published: July 2011

This article describes a developmental series of coordinated stages that can enhance youth development through the integration of recreation and education activities.
Youth development and the camp experience
Authors: Garst Barry A. , Browne Laurie P. , Bialeschki M. Deborah
Published: July 2011

Growth in the volume and rigor of camp research over the past decade has led to improved understanding of the value of the camp experience as a setting for positive youth development and the developmental outcomes of camp experiences for youth and adults, suggesting innovations and opportunities in the exploration of the camp experience.
Outdoor‐based play and reconnection to nature: A neglected pathway to positive youth development
Authors: Mainella Fran P. , Agate Joel R. , Clark Brianna S.
Published: July 2011

For youth today to achieve their full potential, outdoor‐based play and reconnection to nature are essential.
Adventure‐based programming: Exemplary youth development practice
Authors: Sibthorp Jim , Morgan Cass
Published: July 2011

Despite operating on the periphery of academic scholarship, adventure‐based programs can serve as the prototype for how organized and structured youth development programs should function.
Clostridium beijerinckii mutant with high inhibitor tolerance obtained by low-energy ion implantation
Authors: Guo Ting , Tang Yan , Zhang Qiu-yan , Du Teng-fei , Liang Da-feng , Jiang Min , Ouyang Ping-kai
Published: July 2011

Clostridium beijerinckii mutant strain IB4, which has a high level of inhibitor tolerance, was screened by low-energy ion implantation and used for butanol fermentation from a non-detoxified hemicellulosic hydrolysate of corn fiber treated with dilute sulfuric acid (SAHHC). Evaluation of toxicity showed C. beijerinckii IB4 had a higher level of tolerance than parent strain C. beijerinckii NCIMB 8052 for five out of six phenolic compounds tested (the exception was vanillin). Using glucose as carbon source, C. beijerinckii IB4 produced 9.1 g l−1 of butanol with an acetone/butanol/ethanol (ABE) yield of 0.41 g g−1. When non-detoxified SAHHC was used as carbon source, C. beijerinckii NCIMB 8052 grew well but ABE production was inhibited. By contrast, C. beijerinckii IB4 produced 9.5 g l−1 of ABE with a yield of 0.34 g g−1, including 2.2 g l−1 acetone, 6.8 g l−1 butanol, and 0.5 g l−1 ethanol. The remarkable fermentation and inhibitor tolerance of C. beijerinckii IB4 appears promising for ABE production from lignocellulosic materials.
The strong minimum principle for quasisuperminimizers of non-standard growth
Authors: Harjulehto P. , Hästö P. , Latvala V. , Toivanen O.
Published: July 2011

We prove the strong minimum principle for non-negative quasisuperminimizers of the variable exponent Dirichlet energy integral under the assumption that the exponent has modulus of continuity slightly more general than Lipschitz. The proof is based on a new version of the weak Harnack estimate.

Nous prouvons le fort principe du minimum pour des quasisuperminimizeurs non-négatifs de problème de Dirichlet de lʼexposant variable en supposant que lʼexposant a le module de continuité un peu plus général que Lipschitz. La démonstration est fondée sur une nouvelle version de la faible inégalité de Harnack.
Epigenetic, transcriptional and posttranscriptional regulation of the tyrosine hydroxylase gene
Authors: Lenartowski Robert , Goc Anna
Published: July 2011

The activity of tyrosine hydroxylase (TH, EC 1.14.16.2) gene and protein determines the catecholamine level, which, in turn, is crucial for the organism homeostasis. The TH gene expression is regulated by near all possible regulatory mechanisms on epigenetic, transcriptional and posttranscriptional levels. Ongoing molecular characteristic of the TH gene reveals some of the cis and trans elements necessary for its proper expression but most of them especially these responsible for tissue specific expression remain still obscure. This review will focus on some aspects of TH regulation including spatial chromatin organization of the TH locus and TH gene, regulatory elements mediating basal, induced and cell‐specific activity, transcriptional elongation, alternative TH RNA processing, and the regulation of TH RNA stability in the cell.
Modeling Alzheimer's disease progression using the disease system analysis approach
Authors: Gomeni Roberto , Simeoni Monica , Zvartau‐Hind Marina , Irizarry Michael C. , Austin Daren , Gold Michael
Published: July 2011

A novel mechanistic model based on a disease system analysis paradigm was developed to explore the role of homeostatic mechanisms involved in Alzheimer's disease (AD) progression. We used longitudinal AD Assessment Scale‐cognitive subscale (ADAS‐cog) scores from 926 subjects with AD on stable acetylcholinesterase inhibitor therapy randomized to placebo treatment in two 54‐week clinical trials. Alternative mechanistic models were evaluated by assuming that the rate of change of ADAS‐cog over time was jointly regulated by a process characterizing the deterioration of ADAS‐cog and by a process associated with a compensatory regulatory response. The model based on a time‐varying deterioration rate of ADAS‐cog performed better than the model based on a time‐varying homeostatic control. The covariate analysis indicated that baseline Mini‐Mental State Examination score, education, age, and apolipoprotein ε4 genotype had a significant effect on the level and shape of the trajectories of the mean model predicted ADAS‐cog change from baseline.
Enhanced active choice: A new method to motivate behavior change
Authors: Keller Punam Anand , Harlam Bari , Loewenstein George , Volpp Kevin G.
Published: July 2011

High rates of medication non‐adherence have significant public health and economic consequences. In other contexts such as savings behavior, opt‐out policies, in which the alternative preferred by the policy maker is made the default, have gotten great traction but may not be feasible in health care settings. After reviewing previous applications, we present a series of studies, including two field experiments, that test the effectiveness of an alternative, ‘active choice’ policy in which there is no default, but decision makers are required to make a choice (Carroll, Choi, Laibson, Madrian, & Metrick, 2009; Spital, 1993, 1995). In addition, we propose and test a modified version of active choice, that we call ‘enhanced active choice’ that favors one alternative by highlighting losses incumbent in the in the non‐preferred alternative. We recommend Enhanced Active Choice as a complement to automatic enrollment or when automatic enrollment is infeasible or unethical.
Prevalence of Prostate Cancer in Patients With Chronic Spinal Cord Injury
Authors: Patel Nikhil , Ngo Kenneth , Hastings James , Ketchum Nicholas , Sepahpanah Farhad
Published: July 2011

Objective

To determine the prevalence of prostate cancer in patients with chronic spinal cord injury (SCI), with regard to the duration, level, and severity of injury.

Design

Retrospective chart review study.

Setting

Inpatient and outpatient Veterans Affairs spinal cord unit.

Participants

The electronic medical records of 350 veterans with chronic SCI and 344 veterans without SCI as a control group were reviewed.

Main Outcome Measure

Prevalence of prostate cancer in patients with chronic SCI with regard to the duration, level, and severity of injury.

Results

Of 350 veterans with chronic SCI, 7 individuals (2%) had prostate cancer. In comparison, of 344 age‐matched veterans without SCI, 18 (5.2%) had prostate cancer. In SCI group with prostate cancer, 2 patients had motor complete injury (American Spinal Cord Injury Association Impairment Scale [AIS] A and B), and 5 patients had motor incomplete injury (AIS C, D, and E). Patients with SCI and with prostate cancer were slightly older (mean [SD] age, 72.14 ± 8.25 years) than the control group (mean [SD] age, 69.83 ± 8.79 years) with cancer.

Conclusion

Findings from this study indicate a lower prevalence of prostate cancer among veterans with chronic SCI in comparison with age‐matched veterans without SCI. Given the small number of patients with SCI and with prostate cancer in this study, we did not find any statistically significant correlation between the prevalence of prostate cancer and the level, duration, and severity of injury.
Lightning Safety Awareness of Visitors in Three California National Parks
Authors: Weichenthal Lori , Allen Jacoby , Davis Kyle P. , Campagne Danielle , Snowden Brandy , Hughes Susan
Published: July 2011

Objective

To assess the level of lightning safety awareness among visitors at 3 national parks in the Sierra Nevada Mountains of California.

Methods

A 12-question, short answer convenience sample survey was administered to participants 18 years of age and over concerning popular trails and points of interest with known lightning activity. There were 6 identifying questions and 5 knowledge-based questions pertaining to lightning that were scored on a binary value of 0 or 1 for a total of 10 points for the survey instrument. Volunteers in Fresno, California, were used as a control group. Participants were categorized as Sequoia and Kings Canyon National Park (SEKI), frontcountry (FC), or backcountry (BC); Yosemite National Park (YNP) FC or BC; and Fresno. Analysis of variance (ANOVA) was used to test for differences between groups.

Results

467 surveys were included for analysis: 77 in Fresno, 192 in SEKI, and 198 in YNP. National park participants demonstrated greater familiarity with lightning safety than individuals from the metropolitan community (YNP 5.84 and SEKI 5.65 vs Fresno 5.14, P = .0032). There were also differences noted between the BC and FC subgroups (YNP FC 6.07 vs YNP BC 5.62, P = .02; YNP FC 6.07 vs SEKI FC 5.58, P = .02). Overall results showed that participants had certain basic lightning knowledge but lacked familiarity with other key lightning safety recommendations.

Conclusions

While there are statistically significant differences in lightning safety awareness between national parks and metropolitan participants, the clinical impact of these findings are debatable. This study provides a starting point for providing educational outreach to visitors in these national parks.
Signo Dicti Collegii: Instruction for a Fourteenth-century Corporate Badge for the College of Trinity Hall, Cambridge
Authors: Geldof Mark Ryan
Published: July 2011

The 1350 foundation statutes for the College of Trinity Hall, Cambridge, contain unique provisions for a corporate signum or badge. The badge was specifically assigned to the college by its founder, William Bateman, Bishop of Norwich (1289–1355). Over time Bateman's personal arms replaced this signum in identifying the college and its property. The badge is often called Bateman's personal badge, but this is not supported by the statutes of the college or by the evidence of the badge's use in surviving books in the college library. The instructions for the college signum and its specific function in the marking of the college's books represents an interesting development in the indication of corporate, rather than personal, ownership using heraldic insignia. This paper discusses Bateman's instructions for the college signum and the evolution of the Trinity Hall arms.
The Iron Age of the Mun Valley, Thailand
Authors: Higham C F W
Published: July 2011

The archaeological landscape of the Mun River valley in north-east Thailand is dominated by many large, prehistoric settlements. These are easily recognized from the air, since they are encircled by banks and moats. Several of these sites were later occupied under the Angkorian kingdom, and incorporate brick temples. These sites present both an enigma and a challenge. Few have ever been excavated, and then only on a very small scale. This article presents the results of a fifteen-year research programme designed to illuminate the cultural sequences at several sites, investigate the social organization as it changed over time, and to identify the period when the moats and banks were constructed. Three sites have been excavated and a cultural sequence covering more than 2,000 years has been dated. This paper concentrates on the Iron Age (450bc–ad500), a period of effervescent social change that may be linked with population growth, engagement in a maritime trade network that incorporated India and China, the development of militarism and, in due course, the rapid transition into the period of the early states that anticipated the foundation of the kingdom of Angkor.
Cracking the Code: the Warden Abbey Morses, Luxury Metalwork and Patronage at a Cistercian Abbey in the Late Middle Ages
Authors: Carter Michael
Published: July 2011

The three copper-gilt and enamel plaques from Warden Abbey are the most important examples of late medieval metalwork from an English Cistercian abbey. They are currently exhibited at the British Museum and dated to the mid-fifteenth century. A reinterpretation of the monograms decorating the plaques allows their patron to be identified as Abbot Walter Clifton (c1377–97). An analysis of the plaques’ style and iconography also suggests a late fourteenth-century date. Clifton's personal devotions and an unusual aspect of the plaques’ iconography can be explained by reference to the spirituality of the Cistercian Order. The plaques’ closest parallel is a roundel decorated with the badge of Richardii. Evidence from inventories and comparison with Continental material suggests that the Warden plaques were, in all probability, morses, used to fasten a cope.
Molecular and catalytic properties of an arginine kinase from the nematodeAscaris suum
Authors: Nagataki M. , Uda K. , Jarilla B.R. , Tokuhiro S. , Wickramasinghe S. , Suzuki T. , Blair D. , Agatsuma T.
Published: July 2011

We amplified the cDNA coding for arginine kinase (AK) from the parasitic nematodeAscaris suum, cloned it in pMAL plasmid and expressed the enzyme as a fusion protein with the maltose-binding protein. The whole cDNA was 1260 bp, encoding 400 amino acids, and the recombinant protein had a molecular mass of 45,341 Da.Ascaris suumrecombinant AK showed significant activity and strong affinity( K _{m}^{Arg} = 0.126\hairsp mM)for the substratel-arginine. It also exhibited high catalytic efficiency( k _{cat}/ K _{m}^{Arg} = 352)comparable with AKs from other organisms. Sequence analysis revealed high amino acid sequence identity betweenA. suumAK and other nematode AKs, all of which cluster in a phylogenetic tree. However, comparison of gene structures showed thatA. suumAK gene intron/exon organization is quite distinct from that of other nematode AKs. Phosphagen kinases (PKs) from certain parasites have been shown to be potential novel drug targets or tools for detection of infection. The characterization ofA. suumAK will be useful in the development of strategies for control not only ofA. suumbut also of related species infecting humans.
Terramechanics-based wheel–terrain interaction model and its applications to off-road wheeled mobile robots
Authors: Jia Zhenzhong , Smith William , Peng Huei
Published: July 2011

This paper presents a wheel–terrain interaction model, which enables efficient modeling of wheeled locomotion in soft soil and numerical simulations of off-road mobile robots. This modular model is derived based on wheel kinematics and terramechanics and the main focus is on describing the stress distributions along the wheel–terrain interface and the reaction forces exerted on the wheel by the soil. When the wheels are steered, the shear stresses underneath the wheel were modeled based on isotropic assumptions. The forces and torques contributed by the bulldozing effect of the side surfaces is also considered in the proposed model. Furthermore, the influence of grousers, commonly used on smaller mobile robots, was modeled by (1) averaging the normal pressures contributed by the grousers and the wheel concave portion, and (2) assuming that the shear phenomenon takes places along the grouser tips. By integrating the model with multibody system code for vehicle dynamics, simulation studies of various off-road conditions in three-dimensional environments can be conducted. The model was verified by using field experiment data, both for a single-wheel vehicle and a whole vehicle.
State adjustment of redundant robot manipulator based on quadratic programming
Authors: Li Kene , Zhang Yunong
Published: July 2011

To achieve desired configuration, a scheme for state adjustment of a redundant robot manipulator with no end-effector task explicitly assigned and referred to as a state-adjustment scheme is proposed in this paper. Owing to the physical limits in an actual robot manipulator, both joint and joint-velocity limits are incorporated into the proposed scheme for practical purposes. In addition, the proposed state-adjustment scheme is formulated as a quadratic program and resolved at the joint-velocity level. A numerical computing algorithm based on the conversion technique of the quadratic program to linear variational inequalities is presented to address the robot state-adjustment scheme. By employing the state-adjustment scheme, the robot manipulator can automatically move to the desired configuration from any initial configuration with the movement kept within its physical limits. Computer simulation and experimental results using a practical six-link planar robot manipulator with variable joint-velocity limits further verify the realizability, effectiveness, accuracy, and flexibility of the proposed state-adjustment scheme.
Aging and the Body: A Review
Authors: Clarke Laura Hurd , Korotchenko Alexandra
Published: July 2011

Dans cet article, nous examinons les recherches socioculturelles existantes et la théorie concernant le corps vieillissant. En particulier, nous examinons l’image du corps et la littérature de l’incarnation et discutons de ce qui est connu de la façon dont les aînés perçoivent et sentent l’expérience de leur corps vieillissants. Nous analysons comment l’image du corps est influencée par l’âge, la culture, l’origine ethnique, le sexe, l’état de santé, les préferences sexuelles, et la classe sociale. En outre, nous avons élaboré de façon critique la littérature comme mode de réalisation qui a trait aux expériences de la maladie, la sexualité, la gestion quotidienne du corps vieillissante, le travail avec l’apparence et l’identité incarnée. En présentant les principales conclusions, les débats théoriques, et les divergences de fond qui sont présentes dans la recherche et dans la théorie de l’image corporelle et l’incarnation, nous avons identifié les lacunes dans la littérature et avons prévu des axes d’enquête requises à l’avenir.
‘FORGIVE US OUR DEBTS’: VIEWING THE LIFE AND CAREER OF JOHANN FRIEDRICH FASCH (1688–1758) THROUGH THE LENS OF FINANCE
Authors: REUL BARBARA M.
Published: July 2011

This article traces the financial profile of Johann Friedrich Fasch, Kapellmeister of Anhalt-Zerbst from 1722 to 1758, in order to gain a better understanding of how an early eighteenth-century German court musician tried to manage his money. Factors that contributed to his debt problems ranged from personal choices, matters of faith and the need to maintain a certain standard of living as director of music, to the varying degrees of financial support offered by his employers. The period during which he first began incurring debts – his student days in Leipzig – will be examined prior to viewing his professional career path through the lens of finance, beginning with Fasch's first official appointment in Gera in 1715 and ending with his death in Zerbst in 1758. Finally, understanding the extent to which Fasch's personal debts affected his productivity as a composer means not only dealing with the ‘Music-Wechsel’ that he organized and the contents of the court's ‘Concert-Stube’ music inventory from 1743, but also considering Fasch's overall work ethic and integrity as a musician.
Functional derivative of the kinetic energy functional for spherically symmetric systems
Authors: Nagy Á.
Published: July 2011

Ensemble non-interacting kinetic energy functional is constructed for spherically symmetric systems. The differential virial theorem is derived for the ensemble. A first-order differential equation for the functional derivative of the ensemble non-interacting kinetic energy functional and the ensemble Pauli potential is presented. This equation can be solved and a special case of the solution provides the original non-interacting kinetic energy of the density functional theory.
High energy x-ray scattering studies of the local order in liquid Al
Authors: Mauro N. A. , Bendert J. C. , Vogt A. J. , Gewin J. M. , Kelton K. F.
Published: July 2011

The x-ray structure factors and densities for liquid aluminum from 1123 K to 1273 K have been measured using the beamline electrostatic levitator. Atomic structures as a function of temperature have been constructed from the diffraction data with reverse Monte Carlo simulations. An analysis of the local atomic structures in terms of the Honeycutt-Andersen indices indicates a high degree of icosahedral and distorted icosahedral order, a modest amount of body-centered cubic order, and marginal amounts of face-centered cubic and hexagonal close-packed order.
Beneficial and detrimental fatigue effects of dielectric barrier discharges on the piezoelectricity of polypropylene ferroelectrets
Authors: Qiu Xunlin , Wirges Werner , Gerhard Reimund
Published: July 2011

Cellular polypropylene (PP) ferroelectrets combine a large piezoelectricity with mechanical flexibility and elastic compliance. Their charging process represents a series of dielectric barrier discharges (DBDs) that generate a cold plasma with numerous active species and thus modify the inner polymer surfaces of the foam cells. Both the threshold for the onset of DBDs and the piezoelectricity of ferroelectrets are sensitive to repeated DBDs in the voids. It is found that the threshold voltage is approximately halved and the charging efficiency is clearly improved after only 103 DBD cycles. However, plasma modification of the inner surfaces from repeated DBDs deteriorates the chargeability of the voids, leading to a significant reduction of the piezoelectricity in ferroelectrets. After a significant waiting period, the chargeability of previously fatigued voids shows a partial recovery. The plasma modification is, however, detrimental to the stability of the deposited charges and thus also of the macroscopic dipoles and of the piezoelectricity. Fatigue from only 103 DBD cycles already results in significantly less stable piezoelectricity in cellular PP ferroelectrets. The fatigue rate as a function of the number of voltage cycles follows a stretched exponential. Fatigue from repeated DBDs can be avoided if most of the gas molecules inside the voids are removed via a suitable evacuation process.
Introduction of the Floquet-Magnus expansion in solid-state nuclear magnetic resonance spectroscopy
Authors: Mananga Eugène S. , Charpentier Thibault
Published: July 2011

In this article, we present an alternative expansion scheme called Floquet-Magnus expansion (FME) used to solve a time-dependent linear differential equation which is a central problem in quantum physics in general and solid-state nuclear magnetic resonance (NMR) in particular. The commonly used methods to treat theoretical problems in solid-state NMR are the average Hamiltonian theory (AHT) and the Floquet theory (FT), which have been successful for designing sophisticated pulse sequences and understanding of different experiments. To the best of our knowledge, this is the first report of the FME scheme in the context of solid state NMR and we compare this approach with other series expansions. We present a modified FME scheme highlighting the importance of the (time-periodic) boundary conditions. This modified scheme greatly simplifies the calculation of higher order terms and shown to be equivalent to the Floquet theory (single or multimode time-dependence) but allows one to derive the effective Hamiltonian in the Hilbert space. Basic applications of the FME scheme are described and compared to previous treatments based on AHT, FT, and static perturbation theory. We discuss also the convergence aspects of the three schemes (AHT, FT, and FME) and present the relevant references.
Interpretation of the water surface vibrational sum-frequency spectrum
Authors: Pieniazek P. A. , Tainter C. J. , Skinner J. L.
Published: July 2011

We propose a novel interpretation of the water liquid-vapor interface vibrational sum-frequency (VSF) spectrum in terms of hydrogen-bonding classes. Unlike an absorption spectrum, the VSF signal can be considered as a sum of signed contributions from different hydrogen-bonded species in the sample. We show that the recently observed positive feature at low frequency, in the imaginary part of the signal, is a result of cancellation between the positive contributions from four-hydrogen-bonded molecules and negative contributions from those molecules with one or two broken hydrogen bonds. Spectral densities for each of these subgroups span the entire relevant spectral range. Three-body interactions within our newly developed E3B water simulation model prove to be critical in describing the proper balance between different hydrogen-bonded species, as (two-body) SPC/E, TIP4P, and TIP4P/2005 models fail to reproduce the positive feature. The results clarify the molecular origin of the VSF signal, and highlight the importance of many-body interactions for water in heterogeneous situations.
Universal mechanism for breaking amide bonds by ionizing radiation
Authors: Johnson Phillip S. , Cook Peter L. , Liu Xiaosong , Yang Wanli , Bai Yiqun , Abbott Nicholas L. , Himpsel F. J.
Published: July 2011

The photodissociation of the amide bond by UV light and soft x-rays is investigated by x-ray absorption spectroscopy at the C, N, and O 1s edges. Irradiation leaves a clear and universal signature for a wide variety of amides, ranging from oligopeptides to large proteins and synthetic polyamides, such as nylon. As the π* peak of the amide bond shrinks, two new π* peaks appear at the N 1s edge with a characteristic splitting of 1.1 eV. An additional characteristic is the overall intensity reduction of both the π* and σ* features at the O 1s edge, which indicates loss of oxygen. The spectroscopic results are consistent with the release of the O atom from the amide bond, followed by the migration of the H atom from the N to one of its two C neighbors. Migration to the carbonyl C leads to an imine, and migration to the Cα of the amino acid residue leads to a nitrile. Imine and nitrile produce the two characteristic π* transitions at the N 1s edge. A variety of other models is considered and tested against the N 1s spectra of reference compounds.
On the coupling between slow diffusion transport and barrier crossing in nucleation
Authors: Peters Baron
Published: July 2011

We model the coupling between slow diffusion transport and nucleation using the diffusion equation, an Ostwald-Freundlich boundary condition, and a mass balance linking nucleus size to flux across the nucleus-solution interface. The model retains some characteristics of the classical nucleation theory because of the common theoretical foundations behind classical nucleation theory and the Ostwald-Freundlich equation. For example, the classically critical-sized nucleus in the uniform supersaturated concentration field is an unstable equilibrium point. However, the model also shows that certain types of concentration profiles can drive a classically pre-critical nucleus over the nucleation barrier. We identify the separatrix as a function of both nucleus size and characteristics of the local concentration field. Our analysis may be useful for understanding the effects of local concentration fluctuations and especially for understanding the role of dense precursor particles in driving two-step nucleation processes. Our analysis may also provide a starting point for further statistical field theory analyses of local concentration fluctuations and their effects on nucleation rates.
Rotational relaxation characteristics of the monoclinic phase of CCl4
Authors: Zuriaga Mariano , Carignano Marcelo , Serra Pablo
Published: July 2011

We present a study of crystalline CCl4 spanning up to 10 orders of magnitude in time at temperatures ranging from 160 K to 190 K using molecular dynamics simulations. The relaxation process is studied using angular self correlation functions. The results show that each of the four nonequivalent molecules of the monoclinic phase have a particular relaxation time. Two of the molecules relax in an exponential way and the two other molecules have a more complex behavior, especially at the lower temperatures. In all cases, the molecular rotations correspond to quick jumps between equivalent tetrahedral equilibrium positions. Most of these rotations are about the C3 symmetry axes, however at high temperatures, rotations about the C2 symmetry axes are observed as well. The waiting time between rotations follows a Poisson distribution. The calculated relaxation times show an Arrhenius behavior with different activation energy for different nonequivalent molecules, in line with recently published findings of nuclear quadrupole resonance experiments.
High Q microcavity light emitting diodes with buried AlN current apertures
Authors: Cheng Bo-Siao , Wu Yun-Lin , Lu Tien-Chang , Chiu Ching-Hsueh , Chen Cheng-Hung , Tu Po-Min , Kuo Hao-Chung , Wang Shing-Chung , Chang Chun-Yen
Published: July 2011

We demonstrate a GaN-based high-Q microcavity light emitting diode (MCLED) with a buried AlN current aperture. A thin AlN layer is inserted on the InGaN/GaN multiple quantum wells as a current blocking layer and an optical confinement layer. The GaN-based MCLED is composed of a 29-pair GaN/AlN distributed Bragg reflector (DBR), an eight-pair of SiO2/Ta2O5 dielectric DBR, and a three-λ optical thickness InGaN/GaN active region. The current can be injected more effectively in the MCLED with a buried AlN current aperture. The output emission has a dominant emission peak wavelength at 440 nm with a very narrow linewidth of 0.52 nm, corresponding to a cavity Q-value of 846 at a driving current of 5 mA.
Evaluating mark - recapture sampling designs for fish in an open riverine system
Authors: Gwinn Daniel C. , Brown Paul , Tetzlaff Jakob C. , Allen Mike S.
Published: July 2011

Sampling designs for effective monitoring programs are often specific to individual systems and management needs. Failure to carefully evaluate sampling designs of monitoring programs can lead to data that are ineffective for informing management objectives. We demonstrated the use of an individual-based model to evaluate closed-population mark–recapture sampling designs for monitoring fish abundance in open systems, using Murray cod (Maccullochella peelii (Mitchell, 1838)) in the Murray–Darling River basin, Australia, as an example. The model used home-range, capture-probability and abundance estimates to evaluate the influence of the size of the sampling area and the number of sampling events on bias and precision of mark–recapture abundance estimates. Simulation results indicated a trade-off between the number of sampling events and the size of the sampling reach such that investigators could employ large sampling areas with relatively few sampling events, or smaller sampling areas with more sampling events to produce acceptably accurate and precise abundance estimates. The current paper presents a framework for evaluating parameter bias resulting from migration when applying closed-population mark–recapture models to open populations and demonstrates the use of simulation approaches for informing efficient and effective monitoring-program design.
Phylogeography of the copper shark (Carcharhinus brachyurus) in the southern hemisphere: implications for the conservation of a coastal apex predator
Authors: Benavides Martin T. , Feldheim Kevin A. , Duffy Clinton A. , Wintner Sabine , Braccini J. Matias , Boomer Jessica , Huveneers Charlie , Rogers Paul , Mangel Jeffrey C. , Alfaro-Shigueto Joanna , Cartamil Daniel P. , Chapman Demian D.
Published: July 2011

The copper or bronze whaler shark (Carcharhinus brachyurus) is a large, coastal top predator that is vulnerable to overexploitation. We test the null hypothesis that copper sharks are panmictic throughout the southern hemisphere. We analysed part of the mitochondrial control region (mtCR) in 120 individuals from eight sampling areas, defining 20 mtCR haplotypes (h = 0.76 ± 0.06, π = 0.016 ± 0.0007). Significant genetic structure was detected among the following three major coastal regions separated by oceanic habitat: Australia–New Zealand, South Africa–Namibia and Perú (AMOVA ΦST = 0.95, P < 0.000001). A major phylogeographic discontinuity exists across the Indian Ocean, indicating an absence of at least female-mediated gene flow for ~3 million years. We propose that this species originated in the Atlantic, experienced vicariant isolation of Pacific and Atlantic lineages by the rise of the Isthmus of Panama and, subsequently, dispersed across the Pacific to colonise Australasia. Oceanic expanses appear to be traversed over evolutionary but not ecological timescales, which means that regional copper-shark populations should be assessed and managed independently.
Spatial, temporal and ontogenetic variation in the association of fishes (family Labridae) with rocky-reef habitats
Authors: Morton Jason K. , Gladstone William
Published: July 2011

Habitat variability is an important factor structuring fish assemblages of rocky reefs in temperate Australia. Accepting the generality of this model requires that habitat-related variation is consistent through time, across multiple spatial scales, and applies to all life-history stages. We used repeated underwater visual surveys at multiple spatial scales over a 22-month period to test whether three distinct rocky-reef habitats had different wrasse assemblages and whether these assemblages were subject to spatial, temporal and ontogenetic variability. Overall, the strongest and most consistent habitat association was with sponge gardens, which had the most distinct assemblage, and the greatest species richness and density of individuals. Habitat associations in fringe and barrens were less consistent. A substantial increase in the abundance of small individuals, coinciding with warmer sea temperatures, contributed to temporal fluctuations in the density of wrasses. Overall, habitats were not strongly partitioned among larger individuals of the most abundant species, suggesting that adults are largely habitat generalists whereas small, recruiting individuals showed greater habitat specialisation. The present study emphasises the importance of incorporating spatial, temporal and ontogenetic variability into surveys of fish assemblages to understand more fully the dynamics of temperate rocky-reef systems.
Obligatory translation shift as a sub-component of a model of quality assurance specifications and performance translator assessment
Authors: Al-Kufaishi Adil
Published: July 2011

The paper deals primarily with obligatory translation shifts involving translating English texts from and into Arabic and specifies the sub-components of a proposed model of quality assurance specifications and performance translator assessment. Obligatory shifts involve substituting English non-finite embedded forms with finite ones, lexicalizing certain grammatical elements, making agreement in gender between Arabic adjectives and nouns and Arabic nouns and verbs, substituting emphatic ‘do’ with the appropriate rhetorical device, supplying an antecedent to the translated Arabic relative constructions, transposing English initial noun clauses and sentence modifiers to post-verbal positions, placing the definite noun rather than its referent in initial positions, rendering certain English adjectives into verbs, nouns or adjectival clauses, replacing existential ‘there’ and the English grammatical subject ‘it’ with the appropriate corresponding forms, substituting the English comma with the Arabic conjunctive ‘wa’-and or ‘aw’-or as a linking device, deleting the corresponding form of copula be in Arabic interrogatives and replacing certain English noun modifiers with the appropriate similitude construction. The proposed model of quality assurance specifications and performance translator assessment examines the communicative, situational, semantic, structural, stylistic, pragmatic, textual, aesthetic, rhetorical, lexical and informational aspects of the translated text which are essential for assessing the quality of the text and the performance of the translator.
Translating Shakespeare’s imagery for the Chinese audience
Authors: Wong Laurence
Published: July 2011

Generally speaking, the message of a poem is conveyed on three levels: the semantic, the syntactic, and the phonological. How translatable each of these levels is to the translator depends on how much cognation there is between source and target language: the more cognation there is, the more translatable each of these levels. Thus, in respect of all three levels, translation between languages of the same family, such as English and French, both of which belong to the Indo-European family, is easier than translation between languages of different families, such as English and Chinese, which belong respectively to the Indo-European and the Sino-Tibetan family.
If a further distinction is to be made, one may say that, in translation between Chinese and European languages, the semantic level is less challenging than both the syntactic and the phonological level, since syntactic and phonological features are language-bound, and do not lend themselves readily to translation, whereas language pairs generally have corresponding words and phrases on the semantic level to express similar ideas or to describe similar objects, events, perceptions, and feelings.
As an image owes its existence largely to its semantic content, the imagery of a poem is easier to translate than its phonological features. Be that as it may, there is yet another difference: the difference between the imagery of non-dramatic poetry and the imagery of poetic drama when it comes to translation. With reference to Hamlet and its versions in Chinese and in European languages, this paper discusses this difference and the challenges which the translator has to face when translating the imagery of poetic drama from one language into another; it also shows how translating Shakespeare’s imagery from English into Chinese is more formidable than translating it from English into other European languages.