bluuebunny/crossref_metadata_2025 huggingface dataset:
Professor Haverfield: A Bibliography
Authors: Macdonald George
Published: September 2012

The wholly unexpected death of Francis Haverfield on October 1st, 1919, was a grievous loss to the Roman Society. More than any other single individual he had been behind the impulse that led to its foundation. He was its first President, and during his five years' tenure of office he toiled unceasingly to promote its welfare. The Journal in particular owes much to his guiding hand. It will be generally agreed that a tribute to his memory is due. Yet he would probably have thought that a mere personal notice of himself was scarcely appropriate here. A bibliography is different. He was a voluminous writer and, when he wrote with serious intent, his writing was so extraordinarily relevant that it will be unsafe for future workers to neglect what he has said. For the most part, however, his contributions to learning are scattered here and there through a multitude of publications. A list of them is therefore calculated to be of real value to the progress of the studies that lay so near his own heart. In a memorial with such a specific purpose he would certainly have acquiesced.
COST-EFFECTIVENESS OF COMPUTED TOMOGRAPHY COLONOGRAPHY IN COLORECTAL CANCER SCREENING: A SYSTEMATIC REVIEW
Authors: Hanly Paul , Skally Mairead , Fenlon Helen , Sharp Linda
Published: September 2012

Objectives: The European Code Against Cancer recommends individuals aged ≥50 should participate in colorectal cancer screening. CT-colonography (CTC) is one of several screening tests available. We systematically reviewed evidence on, and identified key factors influencing, cost-effectiveness of CTC screening.

Methods: PubMed, Medline, and the Cochrane library were searched for cost-effectiveness or cost-utility analyses of CTC-based screening, published in English, January 1999 to July 2010. Data was abstracted on setting, model type and horizon, screening scenario(s), comparator(s), participants, uptake, CTC performance and cost, effectiveness, ICERs, and whether extra-colonic findings and medical complications were considered.

Results: Sixteen studies were identified from the United States (n = 11), Canada (n = 2), and France, Italy, and the United Kingdom (1 each). Markov state-transition (n = 14) or microsimulation (n = 2) models were used. Eleven considered direct medical costs only; five included indirect costs. Fourteen compared CTC with no screening; fourteen compared CTC with colonoscopy-based screening; fewer compared CTC with sigmoidoscopy (8) or fecal tests (4). Outcomes assessed were life-years gained/saved (13), QALYs (2), or both (1). Three considered extra-colonic findings; seven considered complications. CTC appeared cost-effective versus no screening and, in general, flexible sigmoidoscopy and fecal occult blood testing. Results were mixed comparing CTC to colonoscopy. Parameters most influencing cost-effectiveness included: CTC costs, screening uptake, threshold for polyp referral, and extra-colonic findings.

Conclusion: Evidence on cost-effectiveness of CTC screening is heterogeneous, due largely to between-study differences in comparators and parameter values. Future studies should: compare CTC with currently favored tests, especially fecal immunochemical tests; consider extra-colonic findings; and conduct comprehensive sensitivity analyses.
COST-UTILITY ANALYSIS OF LIRAGLUTIDE VERSUS GLIMEPIRIDE AS ADD-ON TO METFORMIN IN TYPE 2 DIABETES PATIENTS IN CHINA
Authors: Gao Lan , Zhao Fei-Li , Li Shu-Chuen
Published: September 2012

Objectives: The aim of this study was to evaluate the long-term cost-utility of liraglutide versus glimepiride as add-on therapy to metformin in patients with type 2 diabetes mellitus (T2DM), based on the results of clinical trial conducted in Asian population.

Methods: The validated UKPDS Outcomes Model was used to project life expectancy, quality adjusted life-years (QALYs), incidence of diabetes-related complication and cost of complications in patients receiving those regimens. Baseline cohort characteristics and treatment effects were derived from an Asian study. China-specific complication costs and utility score were taken from local studies. Patients’ outcomes were modeled for 30 years and incremental cost-effectiveness ratios were calculated for liraglutide compared with glimepiride from the healthcare system perspective. Both future costs and clinical benefits were discounted at 3 percent. Sensitivity analyses were performed.

Results: Over a period of 30 years, compared with glimepiride, liraglutide 1.8 mg was associated with improvements in life expectancy (0.1 year) and quality adjusted life-year (0.168 QALY), and a reduced incidence of diabetes-related complications leading to an incremental cost-effectiveness ratio per QALY gained versus glimepiride of CNY 25,6871 (DEC 2010, 1 USD = 6.6227 CNY).

Conclusions: Long-term projections indicated that liraglutide was associated with increased life expectancy, QALYs, and reduced complication incidences comparing with glimepiride. When the UK cost of liraglutide was discounted by 38 percent, liraglutide would be a cost-effective option in China from the healthcare system perspective using the 3X GDP/capita per QALY as the WTP threshold.
Knowledge exchange: a review and research agenda for environmental management
Authors: FAZEY IOAN , EVELY ANNA C. , REED MARK S. , STRINGER LINDSAY C. , KRUIJSEN JOANNEKE , WHITE PIRAN C. L. , NEWSHAM ANDREW , JIN LIXIAN , CORTAZZI MARTIN , PHILLIPSON JEREMY , BLACKSTOCK KIRSTY , ENTWISTLE NOEL , SHEATE WILLIAM , ARMSTRONG FIONA , BLACKMORE CHRIS , FAZEY JOHN , INGRAM JULIE , GREGSON JON , LOWE PHILIP , MORTON SARAH , TREVITT CHRIS
Published: September 2012

There is increasing emphasis on the need for effective ways of sharing knowledge to enhance environmental management and sustainability. Knowledge exchange (KE) are processes that generate, share and/or use knowledge through various methods appropriate to the context, purpose, and participants involved. KE includes concepts such as sharing, generation, coproduction, comanagement, and brokerage of knowledge. This paper elicits the expert knowledge of academics involved in research and practice of KE from different disciplines and backgrounds to review research themes, identify gaps and questions, and develop a research agenda for furthering understanding about KE. Results include 80 research questions prefaced by a review of research themes. Key conclusions are: (1) there is a diverse range of questions relating to KE that require attention; (2) there is a particular need for research on understanding the process of KE and how KE can be evaluated; and (3) given the strong interdependency of research questions, an integrated approach to understanding KE is required. To improve understanding of KE, action research methodologies and embedding evaluation as a normal part of KE research and practice need to be encouraged. This will foster more adaptive approaches to learning about KE and enhance effectiveness of environmental management.
Endemicity of leptospirosis in domestic and wild animal species from Reunion Island (Indian Ocean)
Authors: DESVARS A. , NAZE F. , BENNEVEAU A. , CARDINALE E. , MICHAULT A.
Published: September 2012

Leptospirosis is the major infectious disease on Reunion Island but little is known about the animal reservoir. We conducted a wide-ranging survey that included samples from 574 animals belonging to 12 species. The seroprevalence and prevalence of renal carriage varied greatly depending on the species, with the highest seroprevalence (79·5%) found in Norway rats, and the lowest (13·2%) in tenrecs. The renal carriage rate ranged from 84·6% in mice to 0% in tenrecs. Our results suggest that rodents are the most important reservoirs of leptospirosis on Reunion Island. The epidemiological role that animals play in human infection is discussed. For the first time, we quantified the renal concentration of leptospires in ten naturally infected mammals. The history of Reunion Island colonization probably explains why the circulating Leptospira serogroups were similar to those found in Europe. Our study provides evidence that will help implement preventive measures against this zoonosis.
Prevalence of antibodies against measles, mumps and rubella in the childhood population in Singapore, 2008–2010
Authors: ANG L. W. , LAI F. Y. , TEY S. H. , CUTTER J. , JAMES L. , GOH K. T.
Published: September 2012

We undertook a national paediatric seroprevalence survey of measles, mumps and rubella (MMR) in Singapore to assess the impact of the national childhood immunization programme against these three diseases after introduction of the trivalent MMR vaccine in 1990. The survey involved 1200 residual sera of Singapore residents aged 1–17 years collected from two hospitals between 2008 and 2010. The overall prevalence of antibodies against measles, mumps and rubella was 83·1% [95% confidence interval (CI) 80·9–85·1], 71·8% (95% CI 69·1–74·2) and 88·5% (95% CI 86·6–90·2), respectively. For all three diseases, the lowest prevalence was in children aged 1 year (47·8–62·3%). The seroprevalence of the vaccinated children declined over time. The national MMR immunization programme is effective in raising the herd immunity of the childhood population, although certain age groups are more susceptible to infection, in particular, those who are not eligible for vaccination at age <15 months.
Emergency Surgery Data and Documentation Reporting Forms for Sudden-Onset Humanitarian Crises, Natural Disasters and the Existing Burden of Surgical Disease
Authors: Burkle Frederick M. , Nickerson Jason W. , von Schreeb Johan , Redmond Anthony D. , McQueen Kelly A. , Norton Ian , Roy Nobhojit
Published: September 2012

Following large-scale disasters and major complex emergencies, especially in resource-poor settings, emergency surgery is practiced by Foreign Medical Teams (FMTs) sent by governmental and non-governmental organizations (NGOs). These surgical experiences have not yielded an appropriate standardized collection of data and reporting to meet standards required by national authorities, the World Health Organization, and the Inter-Agency Standing Committee's Global Health Cluster. Utilizing the 2011 International Data Collection guidelines for surgery initiated by Médecins Sans Frontières, the authors of this paper developed an individual patient-centric form and an International Standard Reporting Template for Surgical Care to record data for victims of a disaster as well as the co-existing burden of surgical disease within the affected community. The data includes surgical patient outcomes and perioperative mortality, along with referrals for rehabilitation, mental health and psychosocial care. The purpose of the standard data format is fourfold: (1) to ensure that all surgical providers, especially from indigenous first responder teams and others performing emergency surgery, from national and international (Foreign) medical teams, contribute relevant and purposeful reporting; (2) to provide universally acceptable forms that meet the minimal needs of both national authorities and the Health Cluster; (3) to increase transparency and accountability, contributing to improved humanitarian coordination; and (4) to facilitate a comprehensive review of services provided to those affected by the crisis.

BurkleFMJr, NickersonJW, von SchreebJ, RedmondAD, McQueenKA, NortonI, RoyN. Emergency surgery data and documentation reporting forms for sudden-onset humanitarian crises, natural disasters and the existing burden of surgical disease. Prehosp Disaster Med.2012;27(6):1-6.
INTEREST RATE RULES AND MACROECONOMIC STABILITY UNDER HETEROGENEOUS EXPECTATIONS
Authors: Anufriev Mikhail , Assenza Tiziana , Hommes Cars , Massaro Domenico
Published: September 2012

The recent macroeconomic literature stresses the importance of managing heterogeneous expectations in the formulation of monetary policy. We use a simple frictionless dynamic stochastic general equilibrium (DSGE) model to investigate inflation dynamics under alternative interest rate rules when agents have heterogeneous expectations, and update their beliefs based on past performance, as in Brock and Hommes [Econometrica65(5), 1059–1095 (1997)]. The stabilizing effect of different monetary policies depends on the ecology of forecasting rules (i.e., the composition of the set of predictors), on agents' sensitivity to differences in forecasting performance, and on how aggressively the monetary authority sets the nominal interest rate in response to inflation. In particular, if the monetary authority responds only weakly to inflation, a cumulative process with rising inflation is likely. On the other hand, a Taylor interest rate rule that sets the interest rate more than point for point in response to inflation stabilizes inflation dynamics, but does not always lead the system to converge to the rational expectations equilibrium, as multiple equilibria may persist.
Direction asymmetries in spoken and signed language interpreting
Authors: NICODEMUS BRENDA , EMMOREY KAREN
Published: September 2012

Spoken language (unimodal) interpreters often prefer to interpret from their non-dominant language (L2) into their native language (L1). Anecdotally, signed language (bimodal) interpreters express the opposite bias, preferring to interpret from L1 (spoken language) into L2 (signed language). We conducted a large survey study (N = 1,359) of both unimodal and bimodal interpreters that confirmed these preferences. The L1 to L2 direction preference was stronger for novice than expert bimodal interpreters, while novice and expert unimodal interpreters did not differ from each other. The results indicated that the different direction preferences for bimodal and unimodal interpreters cannot be explained by language production–comprehension asymmetries or by work or training experiences. We suggest that modality and language-specific features of signed languages drive the directionality preferences of bimodal interpreters. Specifically, we propose that fingerspelling, transcoding (literal word-for-word translation), self-monitoring, and consumers’ linguistic variation influence the preference of bimodal interpreters for working into their L2.
EVIDENCE AND GOD
Authors: Leech Oliver
Published: September 2012

For many contemporary atheists a significant justification for their belief is the claim that there is no evidence for the existence of God. They compare the lack of evidence for God to the lack of evidence for such beings as leprechauns and goblins. And they point out that for belief in the non-existence of alleged entities such as these it is not necessary to prove the negative, which would not be possible, but it is sufficient to show that after due scrutiny there is a lack of affirmative evidence. We reasonably believe, they argue, that there are no such beings as leprechauns and goblins not because we have found proof that they do not exist but simply because we have found no evidence to suggest that they do exist. And similarly in the case of the existence of God.
POPPER'S PARADOX OF DEMOCRACY
Authors: Rijpkema Bastiaan
Published: September 2012

In a footnote to Chapter 7 of ‘The Open Society and Its Enemies’ Karl Popper describes what he calls the ‘Paradox of Democracy’: the possibility that a majority decides for a tyrant to rule. This is the lesser known paradox of the three to which he pays attention, the other two being the ‘paradox of freedom’ – total freedom leads to suppression of the weak by the strong – and the ‘paradox of tolerance’ – unlimited tolerance leads to the disappearance of tolerance.
Sources of resistance to Fusarium wilt and root-knot nematode in indigenous chickpea germplasm
Authors: Singh Mohar , Khan Z. , Kumar Krishna , Dutta M. , Pathania Anju , Dahiya O. P. , Kumar J.
Published: September 2012

Fusarium wilt caused by Fusarium oxysporum, Schlecht. emend. Snyd. & Hans. f. sp. ciceri is prevalent in most chickpea-growing countries and is a major devastating disease. Host plant resistance is the most practical method of disease management. Indigenous chickpea germplasm reveals a heterogeneous genetic make-up and the response of resistance to wilt is an unexplored potential source for disease resistance. There are 70 indigenous germplasm lines selected on the basis of their agronomic performance and diverse areas of collections in the country. Of these, four accessions had a highly resistant score of 1 and six had a score of 3 using a 1–9 rating scale, indicating their level of resistance to Fusarium wilt (race 4). Other germplasm accessions of chickpea were found to be moderately resistant to highly susceptible disease reaction. Likewise, the same set of germplasm was also screened for Meloidogyne incognita (race 1) using pot culture under controlled condition. Only one accession was found to be resistant to this pest. These resistant gene sources can be utilised effectively for race-specific chickpea wilt and root-knot resistance breeding programmes.
Comparing attitudes and characteristics of organic, former organic and conventional farmers: Evidence from Ireland
Authors: Läpple Doris
Published: September 2012

Despite an overall growth rate of the organic farming sector in the European Union, a considerable number of farmers cease organic production each year. Given the commitment of many European governments to increase the size of their organic farming sectors, reducing the rate of withdrawals from organic production may be an easier option than attracting new farmers into organic farming. In order to reduce the rate of withdrawals, knowledge about those farmers is required. However, to date, little is known about farmers who adopt and subsequently abandon organic farming. This study attempts to fill this gap in the literature by comparing and contrasting the farm and personal characteristics of organic, former organic and conventional farmers. To this end, primary data from 596 Irish cattle and sheep farmers are utilized. Overall, the findings reveal significant differences between the three groups. More specifically, organic farmers are found to be the most environmentally aware farmers, who also rate information gathering as more important than the remaining two groups. Organic farmers are younger, better educated and more likely to be women than conventional farmers. Former organic farmers stand out to be the least risk averse group and also express lower environmental awareness than organic farmers. Conventional farmers are found to be the most profit oriented and least environmentally aware group. In addition, this group farms more intensely stocked enterprises than the remaining groups. The paper concludes with a discussion of some policy recommendations aimed at increasing the size of the organic sector.
Inland and coastal waters
Authors: Mouw Colleen , Greb Steven
Published: September 2012

Workshop for Remote Sensing of Coastal and Inland Waters;Madison, Wisconsin, 20–22 June 2012 Coastal and inland water bodies, which have great value for recreation, food supply, commerce, transportation, and human health, have been experiencing external pressure from direct human activities and climate change. Given their societal and economic value, understanding issues of water quality, water quantity, and the impact of environmental change on the ecological and biogeochemical functioning of these water bodies is of interest to a broad range of communities. Remote sensing offers one of the most spatially and temporally comprehensive tools for observing these waters. While there has been some success with remotely observing these water bodies, many challenges still remain, including algorithm performance, atmospheric correction, the relationships between optical properties and biogeochemical parameters, sufficient spatial and spectral resolution, and a lack of uncertainty estimates over the wide range of environmental conditions encountered across these coastal and inland water bodies.
Geomagnetic excursions date early hominid migration to China
Authors: Bhattacharya Atreyee
Published: September 2012

Global‐scale geomagnetic reversals, which are periods when the direction of Earth's magnetic field flips, leave imprints in magnetic minerals present in sediments. But so do smaller‐scale, even local, changes in Earth's magnetic field direction. Paleomagnetists believe that the smaller‐scale events represent “failed reversals” and refer to them as “geomagnetic excursions.” Scientists use geomagnetic excursions in sedimentary basins as markers to tie together events of Earth's history across the globe.
Long‐term global hurricane activity record shows periodic highs and lows
Authors: Schultz Colin
Published: September 2012

In the long‐record of hurricane activity, which stretches back roughly 7500 years, the frequency of large tropical cyclones has varied, with distinct periods of elevated or depressed activity lasting hundreds to thousands of years. Of the 12 sites that provide the basis for this record, 6 measure the activity in the tropical North Atlantic, 1 serves as a history of the northwestern Pacific, and 5 sites around Australia represent the southwestern Pacific Ocean and the Indian Ocean. In previous research, scientists used the individual records from northern hemispheric sites to investigate the connection between long‐term tropical cyclone activity and climate systems such as the El Niño Southern Oscillation (ENSO). Nott and Forsyth, however, used the records from all 12 sites to ascertain a measure of long‐term global hurricane activity.
Segmentale anti-nozizeptive Effekte durch Dry-needling-Stimulation myofaszialer
Triggerpunkte: Doppelt verblindete randomisierte kontrollierte Studie
Authors: Weber Karin
Published: September 2012

Fragestellung

Die Studie klärt die Frage, ob die Stimulation von Secondary Hyperalgesic Locus (SHL) mit
Dry-needling-Anwendungen eine auf einer segmentalen Neuromodulation basierende
systematische anti-nozizeptive Wirkung hervorruft.
Smallest eigenvalue distributions for two classes of β-Jacobi ensembles
Authors: Dumitriu Ioana
Published: September 2012

We compute the exact and limiting smallest eigenvalue distributions for two classes of β-Jacobi ensembles not covered by previous studies. In the general β case, these distributions are given by multivariate hypergeometric 2F12/β functions, whose behavior can be analyzed asymptotically for special values of β which include \documentclass[12pt]{minimal}\begin{document}$\beta \in 2\mathbb {N}_{+}$\end{document}β∈2N+ as well as for β = 1. Interest in these objects stems from their connections (in the β = 1, 2 cases) to principal submatrices of Haar-distributed (orthogonal, unitary) matrices appearing in randomized, communication-optimal, fast, and stable algorithms for eigenvalue computations [J. Demmel, I. Dumitriu, and O. Holtz, “Fast linear algebra is stable,” Numer. Math. 108, 59–91 (2007)10.1007/s00211-007-0114-x; G. Ballard, J. Demmel, and I. Dumitriu, “Minimizing communication for eigenproblems and the singular value decomposition,” 2010. Preprint].
A simple technique to measure the magnetic susceptibility of liquids
Authors: Chen Zijun , Ellis Joshua , Dahlberg E. Dan
Published: September 2012

A novel technique for measuring the magnetic susceptibility of liquids with modest applied magnetic fields (order of 0.25 T) is presented. The deformation of the liquid surface by a magnetic field is determined by a laser bounce or optical lever technique. The energy balance between the magnetic energy and the gravitational potential of the diamagnetic or paramagnetic liquid interaction is used to determine the susceptibility. The energy due to the surface tension energy is about 10% of the gravitational energy and can be neglected for fast measurements.
Interaction between coinage metal cations M(II) and Xe: CCSD(T) study of MXen2+(M = Cu, Ag, and Au, n = 1–6)
Authors: Xinying Li
Published: September 2012

Quantum chemical calculations of the structures, stabilities, and interactions of the title series at the coupled-cluster single double triple theoretical level are performed. The n = 2 systems are more stable than its neighbors. Topological analysis of the Laplacian, electron density deformation, electron localization function, bond critical point properties, and reduced density gradient analysis are performed to explore the nature of the interaction. The results show that a covalent contribution occurs in the Xe–M2+ intermediate interaction.
Two-dimensional electronic spectroscopy of bacteriochlorophyll a in solution: Elucidating the coherence dynamics of the Fenna-Matthews-Olson complex using its chromophore as a control
Authors: Fransted Kelly A. , Caram Justin R. , Hayes Dugan , Engel Gregory S.
Published: September 2012

Following the observation of long-lived coherences in the two-dimensional (2D) electronic spectra of the Fenna-Matthews-Olson (FMO) complex, many theoretical works suggest that coherences between excitons may play a role in the efficient energy transfer that occurs in photosynthetic antennae. This interpretation of the dynamics depends on the assignment of quantum beating signals to superpositions of excitons, which is complicated by the possibility of observing both electronic and vibrational coherences in 2D spectra. Here, we explore 2D spectra of bacteriochlorophyll a (BChla) in solution in an attempt to isolate vibrational beating signals in the absence of excitonic signals to identify the origin of the quantum beats in 2D spectra of FMO. Even at high laser power, our BChla spectra show strong beating only from the nonresonant response of the solvent. The beating signals that we can conclusively assign to vibrational modes of BChla are only slightly above the noise and at higher frequencies than those previously observed in spectra of FMO. Our results suggest that the beating observed in spectra of FMO is of a radically different character than the signals observed here and can therefore be attributed to electronic coherences or intermolecular degrees of freedom.
Assessment of density functional theory for iron(II) molecules across the spin-crossover transition
Authors: Droghetti A. , Alfè D. , Sanvito S.
Published: September 2012

Octahedral Fe2+ molecules are particularly interesting as they often exhibit a spin-crossover transition. In spite of the many efforts aimed at assessing the performances of density functional theory for such systems, an exchange-correlation functional able to account accurately for the energetic of the various possible spin-states has not been identified yet. Here, we critically discuss the issues related to the theoretical description of this class of molecules from first principles. In particular, we present a comparison between different density functionals for four ions, namely, [Fe(H2O)6]2+, [Fe(NH3)6]2+, [Fe(NCH)6]2+, and [Fe(CO)6]2+. These are characterized by different ligand-field splittings and ground state spin multiplicities. Since no experimental data are available for the gas phase, the density functional theory results are benchmarked against those obtained with diffusion Monte Carlo, one of the most accurate methods available to compute ground state total energies of quantum systems. On the one hand, we show that most of the functionals considered provide a good description of the geometry and of the shape of the potential energy surfaces. On the other hand, the same functionals fail badly in predicting the energy differences between the various spin states. In the case of [Fe(H2O)6]2+, [Fe(NH3)6]2+, [Fe(NCH)6]2+, this failure is related to the drastic underestimation of the exchange energy. Therefore, quite accurate results can be achieved with hybrid functionals including about 50% of Hartree-Fock exchange. In contrast, in the case of [Fe(CO)6]2+, the failure is likely to be caused by the multiconfigurational character of the ground state wave-function and no suitable exchange and correlation functional has been identified.
On the relationship between bond-length alternation and many-electron self-interaction error
Authors: Körzdörfer Thomas , Parrish Robert M. , Sears John S. , Sherrill C. David , Brédas Jean-Luc
Published: September 2012

Predicting accurate bond-length alternations (BLAs) in long conjugated molecular chains has been a major challenge for electronic-structure theory for many decades. While Hartree-Fock (HF) overestimates BLA significantly, second-order perturbation theory and commonly used density functional theory (DFT) approaches typically underestimate it. Here, we discuss how this failure is related to the many-electron self-interaction error (MSIE), which is inherent to both HF and DFT approaches. We use tuned long-range corrected hybrids to minimize the MSIE for a series of polyenes. The key result is that the minimization of the MSIE alone does not yield accurate BLAs. On the other hand, if the range-separation parameter is tuned to yield accurate BLAs, we obtain a significant MSIE that grows with chain length. Our findings demonstrate that reducing the MSIE is one but not the only important aspect necessary to obtain accurate BLAs from density functional theory.
Polymer-stabilized supercooled blue phase
Authors: Choi Hyunseok , Higuchi Hiroki , Ogawa Yukiko , Kikuchi Hirotsugu
Published: September 2012

We report a method to prepare a polymer-stabilized liquid-crystal blue phase that is effective over a wide range of temperature. There are two main key points about this method: (1) A precursor solution is injected into the cell at an enough high temperature above the blue phase–isotropic phase transition point, and (2) a photo-polymerization process with a deeply supercooled blue phase of the precursor solution stabilizes the phase. Thus, a polymer-stabilized “supercooled” blue phase is achieved through photo-polymerization over a wide range of temperature. The proposed method will be very beneficial for manufacturing blue-phase-mode liquid crystal displays.
Adaptable infrared surface plasmon resonance spectroscopy accessory
Authors: Menegazzo Nicola , Kegel Laurel L. , Kim Yoon-Chang , Allen Derrick L. , Booksh Karl S.
Published: September 2012

A second generation prototype enabling surface plasmon resonance spectroscopic measurements in the infrared (IR) range is described. The new design (v2) uses the optical train (optics and detector) within conventional FT-IR spectrometers by confining dimensions of the accessory to space available within the sample compartment of the spectrometer. The v2 accessory builds upon knowledge gained from a previous version that was based on a modified commercial variable angle spectroscopic accessory and addresses observed limitations of the original design—improved temporal stability and measurement acquisition speed, crucial to biomolecular binding studies, as well as optical flexibility, a requirement for investigations of novel plasmon-supporting materials. Different aspects of the accessory, including temporal stability, mechanical resilience, and sensitivity to changes in refractive index of a sample were evaluated and presented in this contribution.
Nanoantenna-like properties of sea-urchin shaped ZnO as a nanolight filter
Authors: Husn Su Yen , Chen Wei-Yu
Published: September 2012

A light scattering peak of ZnO rods is presented at 543.2 nm. The radiation peaks of ZnO nanospines correspond to 496.6 nm and 630.6 nm due to the breaking of the symmetry of the ZnO rods. The radiation peaks of sea-urchin shaped ZnO was observed and confirmed by utilizing the dipole approximation. Sea-urchin shaped ZnO can tune and then filter different frequencies of light by utilizing incident light to illuminate at the different positions of sea-urchin shaped ZnO which works like a nanolight filter device and has potential applications in photonic computers, bio-light emission device, and solar cells.
First principle evaluation of the chiroptical activity of the di-phenyl-diazene derivatives
Authors: Benassi Enrico , Corni Stefano
Published: September 2012

Azobenzene (di-phenyl-diazene) is well-known as a photoisomerisable molecule and has been widely studied as a molecular photoswitcher. Molecular rods, where di-phenyl arms are bound to the diazene moiety, have been also synthesized. In this article we explore by first principle density functional theory calculations the chiroptical properties (electronic circular dichroism spectra, ECD) of azobenzene and its homologues with polyphenyl arms. In particular, we demonstrate that for molecules in the cis configuration the intrinsic chirality of the distorted cis diazene group dominates the ECD response, while for trans species the non-planarity of the polyphenyl arms induces peaks in the ECD spectrum. Finally, the possibility of obtaining a light-controlled chiral switch by proper functionalization is also speculated.
Anomalous temperature dependence of photoluminescence in self-assembled InGaN quantum dots
Authors: Ma Jun , Ji Xiaoli , Wang Guohong , Wei Xuecheng , Lu Hongxi , Yi Xiaoyan , Duan Ruifei , Wang Junxi , Zeng Yiping , Li Jinmin , Yang Fuhua , Wang Chao , Zou Gang
Published: September 2012

Self-assembled InGaN quantum dots (QDs) were fabricated by metal-organic chemical vapor deposition. Abnormal temperature dependence of photoluminescence (PL) was observed. The integrated PL intensity of QDs sample shows a dramatic increase in a temperature range from 160 K to 215 K and reaches the maximum value at 215 K instead of 10 K as usual. To interpret this phenomenon, a theoretic model of temperature induced carrier redistribution mechanism is designed using rate equation, which fits closely with the experimental result. It is concluded that carriers’ redistribution from shallow QDs or wetting layer to deep QDs gives rise to the unique behavior for InGaN QDs structure.
Single-wavelength, all-optical switching based on exciton-polaritons
Authors: Steger M. , Gautham C. , Nelsen B. , Snoke D. , Pfeiffer L. , West K.
Published: September 2012

We present a method for all-optical switching using a microcavity exciton-polariton system. Unlike many other switching methods, we use a single wavelength for both the signal and gate, which means that this method could be used for cascading optical logic gates and amplification within an all-optical circuit. We resonantly pump the sample at an angle with a laser beam and probe the sample with another beam at normal incidence. Upon saturation of the exciton-polariton states, the normal-incidence resonance increases in energy to permit the probe beam to be transmitted through the sample. Experimental results demonstrate switching using a GaAs/AlAs microcavity. Switching times on the order of ten picoseconds and on/off ratios on the order of 10:1 have been observed, and we propose design options to improve upon these.
Noise characteristics of short wavelength infrared InGaAs linear focal plane arrays
Authors: Li Xue , Huang Songlei , Chen Yu , Tang Hengjing , Shao Xiumei , Li Tao , Gong Haimei , Fang Jiaxiong
Published: September 2012

A noise characteristics model is presented for short wavelength infrared (SWIR) focal plane arrays (FPAs). The model shows the relationship between noise and varying integration time. The experimental results for different SWIR InGaAs linear FPAs in the 1.0–1.7 μm and 1.0–2.4 μm spectral range can be well fitted by this model. The noise of InGaAs FPAs with the conventional process in the 1.0–1.7 μm spectral range is determined by the shot noise from the photodiode, which provides a direction for reducing the noise of FPAs. The noise of InGaAs FPAs with the improved process in the 1.0–1.7 μm spectral range is determined by the noise from the readout integrated circuit (ROIC), which is due to the lower shot noise from the dark current of the photodiode. The noise of InGaAs FPAs in the 1.0–2.4 μm spectral range shows a transition from the fixed-pattern noise to the shot noise with a decrease of temperature as indicated by the model. This reduction is mainly due to the higher dark current of photodiodes and the non-uniformity of the dark current. It could be expected that the noise characteristics model is appropriate for the other infrared FPAs. Further, gain constants and conversion efficiencies of the ROIC are obtained according to a signal to noise relationship of the FPAs.
Stable low-fouling plasma polymer coatings on polydimethylsiloxane
Authors: Forster S. , McArthur S. L.
Published: September 2012

Polydimethylsiloxane (DMS) is a popular material for microfluidics, but it is hydrophobic and is prone to non-specific protein adsorption. In this study, we explore methods for producing stable, protein resistant, tetraglyme plasma polymer coatings on PDMS by combining extended baking processes with multiple plasma polymer coating steps. We demonstrate that by using this approach, it is possible to produce a plasma polymer coatings that resist protein adsorption (<10 ng/cm2) and are stable to storage over at least 100 days. This methodology can translate to any plasma polymer system, enabling the introduction of a wide range of surface functionalities on PDMS surfaces.
Positive exchange bias and upward magnetic relaxation in a Fe-film/CoO-nanoparticle hybrid system
Authors: Zhang Wei , Wen Tianlong , Krishnan Kannan M.
Published: September 2012

Unusual positive exchange bias found in Fe/CoOx nanoparticle bilayer films is correlated to a characteristic magnetic spin-glass (SG) in CoOx, with the SG magnetization coupled antiparallel with the Fe magnetization upon field cooling. This SG magnetization has strong field- and time-dependence which displays unusual upward magnetic relaxation behavior in thermoremanent magnetization measurements. The antiparallel coupling is shown to result predominantly from the antiferromagnetic superexchange of the Fe2+-O-Co3+ couple, of the oxygen-terminated CoOx at the interface. These experimental results reveal the possibility of manipulating the exchange bias effect via an indirect exchange coupling mechanism.
Time-domain measurement of a self-amplified spontaneous emission free-electron laser with an energy-chirped electron beam and undulator tapering
Authors: Marcus G. , Artioli M. , Bacci A. , Bellaveglia M. , Chiadroni E. , Cianchi A. , Ciocci F. , Del Franco M. , Di Pirro G. , Ferrario M. , Filippetto D. , Gatti G. , Giannessi L. , Labat M. , Mostacci A. , Petralia A. , Petrillo V. , Quattromini M. , Rau J. V. , Rossi A. R. , Rosenzweig J. B.
Published: September 2012

We report, with an unequivocal time-domain measurement, that an appropriately chosen undulator taper can compensate for an electron beam longitudinal energy-chirp in a free-electron laser amplifier, leading to the generation of single-spike radiation close to the Fourier limit. The measurements were taken using the frequency-resolved optical gating technique by employing an advanced transient-grating diagnostic geometry. The reconstructed longitudinal radiation characteristics are compared in detail to prediction from time-dependent three-dimensional simulations.
Surface label-free sensing by means of a fluorescent multilayered photonic structure
Authors: Descrovi Emiliano , Frascella Francesca , Ballarini Mirko , Moi Valeria , Lamberti Andrea , Michelotti Francesco , Giorgis Fabrizio , Fabrizio Pirri Candido
Published: September 2012

A fluorescent dielectric multilayer is exploited for label-free sensing in aqueous micro-environment. Fluorescence is laser-excited and collected through prism-coupling to a surface electromagnetic mode, also known as Bloch surface waves (BSW) localized at the interface between the multilayer and the outer aqueous medium. By detecting the spectral changes of the BSW-coupled light emission due to an external perturbation of the refractive index (Δn), a sensitivity of ∼2500 nm/RIU and a limit of detection down to Δn ∼ 3 × 10−6 are obtained.
Interpolation of Illusory Pain in the Human Somatosensory System
Authors: Seckel Elizabeth , Krause Beatrix , Ramachandran Vilayanur S
Published: September 2012

Three coins are lined up with the middle coin at room temperature and flanking coins cooled down to 4° C. If digits 2 and 4 are placed on the outer coins and digit 3 on the middle coin, the latter also feels cold; a striking example of perceptual filling in of temperature. We show that if digits 2 and 4 are placed on a thermal grill with alternating hot and cold bars, while digit 3 is placed on cardboard, the sensation of pain will also spread to the middle finger.
Luminance Profiles of Luminance Gradients Affect the Feeling of Dazzling
Authors: Hanada Mitsuhiko
Published: September 2012

The feeling of dazzling that is evoked by luminance gradients was examined. The stimulus consisted of a disk with uniform luminance surrounded by an annulus whose luminance was decreased from the inner boundary to the periphery. Three luminance profiles (linear, logistic, and inverse logistic) of a surrounding luminance ramp were used. The luminance of the disk and the maximum luminance of the annulus were also varied. The feeling of dazzling became stronger as the luminance of the disk and the maximum luminance of the annulus increased. The effect of the maximum luminance of the annulus was greater for the disk with low luminance than for that with high luminance. The feeling of dazzling tended to be greater for the logistic profile than for the other profiles. However, when the luminance of the disk and that at the inner boundary of the annulus were the same, the feeling of dazzling for the logistic profile was no stronger than that for the linear or the inverse-logistic profile. These results suggest that smooth transition from the disk to the annulus for the logistic profile suppresses the feeling of dazzling.
Eye and Hand Movements during Reconstruction of Spatial Memory
Authors: Burke Melanie R , Allen Richard J , Gonzalez Claudia
Published: September 2012

Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (eg Awh et al, 2006 Neuroscience139 201–208). This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change) from an array presented either simultaneously or sequentially. The time delay between target presentation and recall (0,5, or 10 s) and the number of locations to be remembered (2–5) were also manipulated. Analysis of the response phase revealed subjects were less accurate (touch data) and fixated longer (eye data) when responding to sequentially presented targets suggesting higher cognitive effort. Fixation duration on target at recall was also influenced by whether spatial location was initially signalled by colour or shape change. Finally, we found that the sequence tasks encouraged longer fixations on the signalled targets than simultaneous viewing during encoding, but no difference was observed during recall. We conclude that the attentional manipulations (colour/shape) mainly affected the eye movement parameters, whereas the memory manipulation (sequential versus simultaneous, number of items) mainly affected the performance of the hand during recall, and thus the latter is more important for ascertaining if an item is remembered or forgotten. In summary, the nature of the stimuli that is used and how it is presented play key roles in determining subject performance and behaviour during spatial memory tasks.
Smoke plume height measurement of prescribed burns in the south-eastern United States
Authors: Liu Yongqiang , Goodrick Scott L. , Achtemeier Gary L. , Forbus Ken , Combs David
Published: September 2012

Smoke plume height is important for modelling smoke transport and resulting effects on air quality. This study presents analyses of ceilometer measurements of smoke plume heights for twenty prescribed burns in the south-eastern United States. Measurements were conducted from mid-winter to early summer between 2009 and 2011. Approximately half of the burns were on tracts of land over 400ha (1000 acres) in area. Average smoke plume height was ~1km. Plume height trended upward from winter to summer. These results could be used as an empirical guideline for fire managers to estimate smoke plume height in the south-eastern US when modelling and measurement are not available. The average could be used as a first-order approximation, and a second-order approximation could be obtained by using the average for spring and autumn seasons, and decreasing or increasing by 0.2km the average for winter or summer. The concentrations of particulate matter with an aerodynamic diameter less than 2.5 or 10μm (PM2.5 and PM10) within smoke plumes calculated from ceilometer backscatter are ~80 and 90μgm–3, and trend downward from winter to summer. Large smoke concentrations are found in the lower portion of smoke plumes for many burns. Smoke plume height shows fast and uniform fluctuations at minute scales for almost all burns and slow and irregular fluctuations at scales from tens of minutes to hours for some burns.
High Ca2+ permeability of a peptide-gated DEG/ENaC from Hydra
Authors: Dürrnagel Stefan , Falkenburger Björn H. , Gründer Stefan
Published: September 2012

Degenerin/epithelial Na+ channels (DEG/ENaCs) are Na+ channels that are blocked by the diuretic amiloride. In general, they are impermeable for Ca2+ or have a very low permeability for Ca2+. We describe here, however, that a DEG/ENaC from the cnidarian Hydra magnipapillata, the Hydra Na+ channel (HyNaC), is highly permeable for Ca2+ (PCa/PNa = 3.8). HyNaC is directly gated by Hydra neuropeptides, and in Xenopus laevis oocytes expressing HyNaCs, RFamides elicit currents with biphasic kinetics, with a fast transient component and a slower sustained component. Although it was previously reported that the sustained component is unselective for monovalent cations, the selectivity of the transient component had remained unknown. Here, we show that the transient current component arises from secondary activation of the Ca2+-activated Cl− channel (CaCC) of Xenopus oocytes. Inhibiting the activation of the CaCC leads to a simple on–off response of peptide-activated currents with no apparent desensitization. In addition, we identify a conserved ring of negative charges at the outer entrance of the HyNaC pore that is crucial for the high Ca2+ permeability, presumably by attracting divalent cations to the pore. At more positive membrane potentials, the binding of Ca2+ to the ring of negative charges increasingly blocks HyNaC currents. Thus, HyNaC is the first member of the DEG/ENaC gene family with a high Ca2+ permeability.
MITD1 is recruited to midbodies by ESCRT-III and participates in cytokinesis
Authors: Lee Seongju , Chang Jaerak , Renvoisé Benoît , Tipirneni Anita , Yang Sarah , Blackstone Craig
Published: September 2012

Diverse cellular processes, including multivesicular body formation, cytokinesis, and viral budding, require the sequential functions of endosomal sorting complexes required for transport (ESCRTs) 0 to III. Of these multiprotein complexes, ESCRT-III in particular plays a key role in mediating membrane fission events by forming large, ring-like helical arrays. A number of proteins playing key effector roles, most notably the ATPase associated with diverse cellular activities protein VPS4, harbor present in microtubule-interacting and trafficking molecules (MIT) domains comprising asymmetric three-helical bundles, which interact with helical MIT-interacting motifs in ESCRT-III subunits. Here we assess comprehensively the ESCRT-III interactions of the MIT-domain family member MITD1 and identify strong interactions with charged multivesicular body protein 1B (CHMP1B), CHMP2A, and increased sodium tolerance-1 (IST1). We show that these ESCRT-III subunits are important for the recruitment of MITD1 to the midbody and that MITD1 participates in the abscission phase of cytokinesis. MITD1 also dimerizes through its C-terminal domain. Both types of interactions appear important for the role of MITD1 in negatively regulating the interaction of IST1 with VPS4. Because IST1 binding in turn regulates VPS4, MITD1 may function through downstream effects on the activity of VPS4, which plays a critical role in the processing and remodeling of ESCRT filaments in abscission.