bluuebunny/crossref_metadata_2025 huggingface dataset:
Precision and long‐term stability of clumped‐isotope analysis of CO2 using a small‐sector isotope ratio mass spectrometer
Authors: Yoshida Naohiro , Vasilev Mikhail , Ghosh Prosenjit , Abe Osamu , Yamada Keita , Morimoto Maki
Published: December 2012

RATIONALE

The ratio of the measured abundance of 13C–18O bonding CO2 to its stochastic abundance, prescribed by the δ13C and δ18O values from a carbonate mineral, is sensitive to its growth temperature. Recently, clumped‐isotope thermometry, which uses this ratio, has been adopted as a new tool to elucidate paleotemperatures quantitatively.

METHODS

Clumped isotopes in CO2 were measured with a small‐sector isotope ratio mass spectrometer. CO2 samples digested from several kinds of calcium carbonates by phosphoric acid at 25 °C were purified using both cryogenic and gas‐chromatographic separations, and their isotopic composition (δ13C, δ18O, Δ47, Δ48 and Δ49 values) were then determined using a dual‐inlet Delta XP mass spectrometer.

RESULTS

The internal precisions of the single gas Δ47 measurements were 0.005 and 0.02 ‰ (1 SE) for the optimum and the routine analytical conditions, respectively, which are comparable with those obtained using a MAT 253 mass spectrometer. The long‐term variations in the Δ47 values for the in‐house working standard and the heated CO2 gases since 2007 were close to the routine, single gas uncertainty while showing seasonal‐like periodicities with a decreasing trend. Unlike the MAT 253, the Delta XP did not show any significant relationship between the Δ47 and δ47 values.

CONCLUSIONS

The Delta XP gave results that were approximately as precise as those of the MAT 253 for clumped‐isotope analysis. The temporal stability of the Delta XP seemed to be lower, although an advantage of the Delta XP was that no dependency of δ47 on Δ47 was found. Copyright © 2012 John Wiley & Sons, Ltd.
Rapid quantitation of ascorbic and folic acids in SRM 3280 multivitamin/multielement tablets using flow‐injection tandem mass spectrometry
Authors: Bhandari Deepak , Kertesz Vilmos , Van Berkel Gary J.
Published: December 2012

RATIONALE

Ascorbic acid (AA) and folic acid (FA) are water‐soluble vitamins and are usually fortified in food and dietary supplements. For the safety of human health, proper intake of these vitamins is recommended. Improvement in the analysis time required for the quantitative determination of these vitamins in food and nutritional formulations is desired.

METHODS

A simple and fast (~5 min) in‐tube sample preparation was performed, independently for FA and AA, by mixing extraction solvent with a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Quantitative detection was achieved by flow‐injection (1 μL injection volume) electrospray ionization tandem mass spectrometry (ESI‐MS/MS) in negative ion mode using the method of standard addition.

RESULTS

The method of standard addition was employed for the quantitative estimation of each vitamin in a sample extract. At least 2 spiked and 1 non‐spiked sample extract were injected in triplicate for each quantitative analysis. Given an injection‐to‐injection interval of approximately 2 min, about 18 min was required to complete the quantitative estimation of each vitamin. The concentration values obtained for the respective vitamins in the standard reference material (SRM) 3280 using this approach were within the statistical range of the certified values provided in the NIST Certificate of Analysis. The estimated limit of detections of FA and AA were 13 and 5.9 ng/g, respectively.

CONCLUSIONS

Flow‐injection ESI‐MS/MS was successfully applied for the rapid quantitation of FA and AA in SRM 3280 multivitamin/multielement tablets. Published 2012. This article is a US Government work and is in the public domain in the USA.
Carbon, hydrogen and oxygen stable isotope ratios of whole wood, cellulose and lignin methoxyl groups of Picea abies as climate proxies
Authors: Gori Y. , Wehrens R. , Greule M. , Keppler F. , Ziller L. , La Porta N. , Camin F.
Published: December 2012

RATIONALE

Carbon, hydrogen and oxygen (C, H and O) stable isotope ratios of whole wood and components are commonly used as paleoclimate proxies. In this work we consider eight different proxies in order to discover the most suitable wood component and stable isotope ratio to provide the strongest climate signal in Picea abies in a southeastern Alpine region (Trentino, Italy).

METHODS

δ13C, δ18O and δ2H values in whole wood and cellulose, and δ13C and δ2H values in lignin methoxyl groups were measured. Analysis was performed using an Isotopic Ratio Mass Spectrometer coupled with an Elemental Analyser for measuring 13C/12C and a Pyrolyser for measuring 2H/1H and 18O/16O. The data were evaluated by Principal Component Analysis, and a simple Pearson's correlation between isotope chronologies and climatic features, and multiple linear regression were performed to evaluate the data.

RESULTS

Each stable isotope ratio in cellulose and lignin methoxyl differs significantly from the same stable isotope ratio in whole wood, the values begin higher in cellulose and lignin except for the lignin δ2H values. Significant correlations were found between the whole wood and the cellulose fractions for each isotope ratio. Overall, the highest correlations with temperature were found with the δ18O and δ2H values in whole wood, whereas no significant correlations were found between isotope proxies and precipitation.

CONCLUSIONS

δ18O and δ2H values in whole wood provide the best temperature signals in Picea abies in the northern Italian study area. Extraction of cellulose and lignin and analysis of other isotopic ratios do not seem to be necessary. Copyright © 2012 John Wiley & Sons, Ltd.
Investigations of chemical warfare agents and toxic industrial compounds with proton‐transfer‐reaction mass spectrometry for a real‐time threat monitoring scenario
Authors: Kassebacher Thomas , Sulzer Philipp , Jürschik Simone , Hartungen Eugen , Jordan Alfons , Edtbauer Achim , Feil Stefan , Hanel Gernot , Jaksch Stefan , Märk Lukas , Mayhew Chris A. , Märk Tilmann D.
Published: December 2012

RATIONALE

Security and protection against terrorist attacks are major issues in modern society. One especially challenging task is the monitoring and protection of air conditioning and heating systems of buildings against terrorist attacks with toxic chemicals. As existing technologies have low selectivity, long response times or insufficient sensitivity, there is a need for a novel approach such as we present here.

METHODS

We have analyzed various chemical warfare agents (CWAs) and/or toxic industrial compounds (TICs) and related compounds, namely phosgene, diphosgene, chloroacetone, chloroacetophenone, diisopropylaminoethanol, and triethyl phosphate, utilizing a high‐resolution proton‐transfer‐reaction time‐of‐flight mass spectrometry (PTR‐TOFMS) instrument with the objective of finding key product ions and their intensities, which will allow a low‐resolution quadrupole mass spectrometry based PTR‐MS system to be used with high confidence in the assignment of threat agents in the atmosphere.

RESULTS

We obtained high accuracy PTR‐TOFMS mass spectra of the six compounds under study at two different values for the reduced electric field in the drift tube (E/N). From these data we have compiled a table containing product ions, and isotopic and E/N ratios for highly selective threat compound detection with a compact and cost‐effective quadrupole‐based PTR‐MS instrument. Furthermore, using chloroacetophenone (tear gas), we demonstrated that this instrument's response is highly linear in the concentration range of typical Acute Exposure Guideline Levels (AEGLs).

CONCLUSIONS

On the basis of the presented results it is possible to develop a compact and cost‐effective PTR‐QMS instrument that monitors air supply systems and triggers an alarm as soon as the presence of a threat agent is detected. We hope that this real‐time surveillance device will help to seriously improve safety and security in environments vulnerable to terrorist attacks with toxic chemicals. Copyright © 2012 John Wiley & Sons, Ltd.
Electron ionization of different large perfluoroethers embedded in ultracold helium droplets: effective freezing of short‐lived decomposition intermediates
Authors: Bartl P. , Tanzer K. , Mitterdorfer C. , Karolczak S. , Illenberger E. , Denifl S. , Scheier P.
Published: December 2012

RATIONALE

Electron ionization of three perfluoroethers (PFEs), C6F14O3, C8F18O4, and C10F20O5, is studied in the gas phase and when the molecules are embedded in ultracold helium (He) droplets. The molecules investigated are model compounds for perfluoropolyethers used as lubricants in technical applications. The present study gives insight into possible radiolysis pathways upon radiation exposure.

METHODS

The experiments utilized a crossed electron/droplet beam apparatus consisting of a He droplet source and pick‐up chamber combined with a commercial time‐of‐flight mass spectrometer. The doped droplets were ionized by electron ionization at 70 eV.

RESULTS

The He environment strongly affects the ionization patterns in the way that both the molecular ion M+ and high‐mass fragment ions formed by the loss of light neutral species such as F ([M–F]+), or CF3OCF2 ([M–CF3OCF2]+), etc., became strong signals in the mass spectrum. These signals were not or only barely visible in the gas‐phase experiment and were identified as short lived (< µs) dissociation intermediates which in the gas phase immediately decomposed into lower‐mass fragment ions.

CONCLUSIONS

Ionic fragmentation intermediates are frozen and subsequently stabilized in the He environment. Helium droplets can hence be viewed as a cryogenic laboratory transforming short‐lived decomposition intermediates into stable fragment ions appearing as strong signals in the mass spectrum. Copyright © 2012 John Wiley & Sons, Ltd.
Role of cerebroplacental ratio for fetal assessment in prolonged pregnancy
Authors: D'Antonio F. , Patel D. , Chandrasekharan N. , Thilaganathan B. , Bhide A.
Published: December 2012

Objective

The aim of this study was to assess the role of the cerebroplacental ratio (CPR), i.e. the ratio between the middle cerebral artery and umbilical artery pulsatility indices, in detecting fetal compromise in prolonged pregnancy.

Methods

Women attending a dedicated postdates clinic at 41 weeks' gestation were recruited for the study and CPR was calculated at 41+3 weeks. Induction of labor was offered at 42 weeks to those women still undelivered. Unfavorable outcome was defined as cord arterial pH < 7.15 with a base deficit of > 11 mM/L or operative delivery for abnormal intrapartum fetal electrocardiogram ST‐segment analysis. The 5th centiles of the CPR, obtained from published reference ranges (0.90) and from our population (0.98), were used as lower cut‐off values.

Results

Three hundred and twenty women who reached a gestational age of over 41 weeks were eligible for inclusion in the study. The median gestational age at delivery was 294 (range, 289–300) days. Unfavorable outcome was observed in 58/320 pregnancies. There was no significant difference in the proportion of unfavorable outcomes between the two groups defined using either CPR cut‐off value (both P > 0.05).

Conclusion

CPR is not predictive of unfavorable outcome in women with pregnancies lasting more than 41 weeks. Copyright © 2012 ISUOG. Published by John Wiley & Sons Ltd.
Effective Theories of Classical Gravity
Authors: Wells James D.
Published: December 2012

If the concepts underlying Effective Theory were appreciated from the earliest days of Newtonian gravity, Le Verrier’s announcement in 1845 of the anomalous perihelion precession of Mercury would have been no surprise. Furthermore, the size of the effect could have been anticipated through “naturalness” arguments well before the definitive computation in General Relativity. Thus, we have an illustration of how Effective Theory concepts can guide us in extending our knowledge to “new physics”, and not just in how to reduce larger theories to restricted (e.g., lower energy) domains.
A Nodal Positivity Constant: New Perspectives in Lymph Node Evaluation and Colorectal Cancer
Authors: Hogan Niamh M. , Winter Desmond C.
Published: December 2012

Purpose

To date, associations between the number of lymph nodes evaluated, staging, and survival have been examined in the context of large population‐based studies conducted by a small number of investigators. Therefore, although high‐quality data are available, perspective is lacking.

Methods

Studies for this paper were identified by searches of Medline, Scopus, PubMed, and manual searching of references from articles, using the search terms ‘‘colorectal cancer’’, ‘‘nodal status’’ and ‘‘lymph node’’.

Results

It is clear that survival benefit increases with the increasing number of lymph nodes harvested. Despite this observation, there has been no significant increase in the proportion of node‐positive cancers over the past two decades.

Conclusion

The nodal positivity rate for colorectal cancer consistently approximates 40 % across a wide range of studies internationally, a phenomenon that has not previously been recognized in the literature. We review the evidence and introduce the concept of a nodal positivity constant.
Acceptance and Commitment Therapy in Genetic Counselling: A Case Study of Recurrent Worry
Authors: Broley Stephanie
Published: December 2012

I present a case study where the mother of a child with 22q11 deletion disorder appeared to be experiencing recurrent, intrusive worry associated with the inherent uncertainty of this highly variable condition. Counselling sessions are summarised followed by an in‐depth reflection about the case with reference to the main therapeutic tenets of Acceptance and Commitment Therapy (ACT). Specific techniques which may have been of great benefit to the client and potential application in the genetic counselling setting are explored in the context of ACT.
Hydrological changes and paleoproductivity in the Gulf of California during middle and late Holocene and their relationship with ITCZ and North American Monsoon variability
Authors: Pérez-Cruz Ligia
Published: December 2012

This study investigates changes in precipitation patterns and variations in paleoproductivity in the tropical Pacific region associated with the North American Monsoon, Intertropical Convergence Zone (ITCZ) latitudinal migration, and changes in insolation during the middle and late Holocene. Major and trace element records (Al, Ba, C, K, Si and Ti) and Zr/Al and Ba/Al ratios in a core from Alfonso Basin, southern Gulf of California, are used as proxies of terrigenous input and bio-productivity. Records reveal an increase in precipitation and low bio-productivity ca. 6200 to 2400 cal yr BP, associated with the strengthening of monsoonal precipitation and northward shift of the ITCZ mean position in the eastern tropical Pacific. A multi-centennial drought from ca. 2400 to 1900 cal yr BP, and a dry and cold interval ca. 700 and 500 cal yr BP, are characterized by strong aeolian input and enhanced productivity, associated with diminution of the summer monsoonal precipitation and reduced insolation in the Northern Hemisphere and more southerly ITCZ position. Correlation of Alfonso Basin records with other records in the Gulf of California and the Pigmy and Cariaco basins in the Gulf of Mexico and central Atlantic provides constraints on NAM, ITCZ migration, and insolation-driven changes.
The Peculiars of the University of Cambridge
Authors: Steinberg Burkhard
Published: December 2012

Are the University of Cambridge and its colleges peculiars? The university has always claimed independence from episcopal authority for itself and its colleges. A struggle was resolved in 1434 by a tribunal set up by the Pope, in which the Prior of the monastery of Barnwell heard both sides and decided that the University and its colleges were to be exempt from the supervision of the Archbishop of Canterbury and of the Bishop of Ely, in whose diocese the University was situated. This became known as the Barnwell Process. It established the University and it colleges as peculiars defined as having an Ordinary other than the diocesan bishop. Colleges founded later but before the Reformation claimed the same privileges. At the Reformation, the authority of the Pope was replaced by that of the King and the Archbishop of Canterbury, but the privileges that the University and its colleges enjoyed continued to apply. Post-Reformation foundations of colleges tended to claim the same exemptions from episcopal jurisdiction, but without documented evidence. This article argues that the continued acceptance by the Bishop of Ely of the University and its colleges as extra-diocesan confirms them to be peculiars within the legal definition.
General Synod of the Church of Ireland
Authors: Davey Michael
Published: December 2012

Although six bills appeared on the agenda paper for Dublin this year there was only one of real substance. Two were to correct some cross-references in previous legislation, one was of a technical nature relating to voluntary pension contributions and a further bill imposed a requirement on dioceses to provide statistics to central Church bodies when demanded.
The Russian School Twin Registry (RSTR): Project PROGRESS
Authors: Kovas Yulia , Galajinsky Eduard V. , Boivin Michel , Harold Gordon T. , Jones Alice , Lemelin Jean-Pascal , Luo Yu , Petrill Stephen A. , Plomin Robert , Tikhomirova Tatiana , Zhou Xinlin , Malykh Sergey
Published: December 2012

The Russian School Twin Registry (RSTR) was established in 2012, supported by a grant from the Government of the Russian Federation. The main aim of the registry is to contribute to Progress in Education through Gene-Environment Studies (PROGRESS). The formation of the registry is ongoing and it is expected that most schools in the Russian Federation (approximately 50,000 schools) will contribute data to the registry. With a total of 13.7 million students in Grades 1–11 (ages 7–18), the potential number of twin pairs exceeds 100,000. Apart from the large sample size and its representative nature, the RSTR has one unique feature: in collaboration with the International Advisory Committee to the Registry, genetically sensitive cross-cultural investigations are planned, aided by the use of the common assessment instruments. Other strengths of the registry include the assessment of a large sample of non-twin school children, including those studying in the same classes as the twins in the registry. It is hoped that the RSTR will provide an important research platform for national and international educationally relevant research.
Arbeitszufriedenheit von IT-Freelancern
Authors: Süß Stefan , Haarhaus Benjamin
Published: December 2012

Trotz der seit Jahren steigenden Anzahl hochqualifizierter IT-Freelancer bestehen kaum empirische Erkenntnisse über ihre Arbeitszufriedenheit. Da die Auswirkungen der hohen Flexibilitätsanforderungen, der starken Arbeitsbelastung und der unsicheren Einkommenssituation von Freelancern auf ihre Arbeitszufriedenheit folglich unklar sind, wurde untersucht, welche Ausprägungen von Arbeitszufriedenheitstypen bei IT-Freelancern bestehen und inwiefern Unterschiede zu festangestellten IT-Mitarbeitern existieren. Hierzu wurde eine an die Fragestellung angepasste Version des Fragebogen zur Erhebung von Arbeitszufriedenheitstypen (FEAT; Ferreira, 2009 ) verwendet. Es zeigen sich sowohl Gemeinsamkeiten als auch Unterschiede zwischen den Arbeitszufriedenheitstypen in beiden Beschäftigungsformen, die sich vor allem auf unterschiedliche Ausmaße an Autonomie und Einkommenssicherheit zurückführen lassen. Die Studie leistet damit sowohl einen Beitrag zur Erforschung der Arbeitszufriedenheit von IT-Freelancern als auch zur Etablierung eines neuen, theoriebasierten Verfahrens zur Messung von Arbeitszufriedenheit.
Deriving robust return periods for tropical cyclone inundations from sediments
Authors: Nott Jonathan F. , Jagger Thomas H.
Published: December 2012

Return periods for tropical cyclone (TC) marine inundations are usually derived from synthetic data sets generated from deterministic models or by extrapolating short historical records. Such approaches contain considerable uncertainties because it is difficult to test their veracity until a sufficiently long period has elapsed. These approaches also often only consider storm surges or storm tides and not the total inundation, which includes waves, set‐up and run‐up, likely to flood a coastal property. An alternative approach is to examine sedimentary records of actual events that occurred throughout the late Holocene. Sedimentary beach ridges are unique amongst the different types of storm inundation sedimentary records because they record variations in the height of total marine inundations rather than a censoring level as occurs with overwash deposits. The limitation in using beach ridges to derive return periods for inundations has been the lack of a robust statistical model that accurately describes the distribution of these events over the past several millennia. Such a model is presented here using a Generalized Extreme Value distribution and Bayesian analysis of a sand beach ridge plain record of extreme TC‐generated marine inundations from northeast Australia. Using this approach, the return period of the marine inundation generated by severe TC Yasi is determined. This return period differs considerably from estimates determined using a probability‐based approach, which extrapolates from a short historical record. With global climate changing and the magnitude of marine inundations expected to increase, there is mounting pressure to develop national standards for marine flood loadings on coastal buildings. Deriving accurate return periods of these events will be critical to this endeavor, and this approach will be applicable at numerous localities globally where storm deposited beach ridges occur.
Crustal thickness and support of topography on Venus
Authors: James Peter B. , Zuber Maria T. , Phillips Roger J.
Published: December 2012

The topography of a terrestrial planet can be supported by several mechanisms: (1) crustal thickness variations, (2) density variations in the crust and mantle, (3) dynamic support, and (4) lithospheric stresses. Each of these mechanisms could play a role in compensating topography on Venus, and we distinguish between these mechanisms in part by calculating geoid‐to‐topography ratios and apparent depths of compensation. By simultaneously inverting for mass anomalies at two depths, we solve for the spatial distribution of crustal thickness and a similar map of mass anomalies in the mantle, thus separating the effects of shallow and deep compensation mechanisms on the geoid. The roughly circular regions of mantle mass deficit coincide with the locations of what are commonly interpreted to be buoyant mantle plumes. Additionally, there is a significant geographic correlation between patches of thickened crust and mass deficits in the mantle, especially for spherical harmonic degree l < 40. These mass deficits may be interpreted either as lateral thermal variations or as Mg‐rich melt residuum. The magnitudes of mass deficits under the crustal highlands are roughly consistent with a paradigm in which highland crust is produced by melting of upwelling plumes. The mean thickness of the crust is constrained to a range of 8–25 km, somewhat lower than previous estimates. The best two‐layered inversion of gravity incorporates a dynamic mantle load at a depth of 250 km.
HF wave scattering by field‐aligned plasma irregularities considering refraction in the ionosphere
Authors: Galushko V. G. , Bezrodny V. G. , Koloskov A. V. , Paznukhov V. V. , Reinisch B. W.
Published: December 2012

This paper analyzes the effect of ionospheric refraction on the scattering of high frequency (HF) signals by random field‐aligned irregularities in the upper ionosphere. Ray optics calculations are made using the perturbation method for a plane‐stratified (on average) ionosphere, i.e., the incident and scattered waves are both supposed to propagate along the undisturbed trajectories with neglect of the geomagnetic field effect. The equation for the so‐called cone of aspect‐sensitive scattering is derived to relate the trajectory characteristics of the incident and aspect‐sensitive scattered signals. The Born approximation is applied to calculate the scattering cross‐section for the anisotropic power law model spectrum of random irregularities of the upper ionosphere. The possibility of excitation of the ionospheric interlayer waveguide by the aspect‐sensitive scattered HF signals is analyzed in detail for the specific conditions of the HF heating experiment at European Incoherent Scatter (EICSAT).
Microbial composition affects the functioning of estuarine sediments
Authors: Reed Heather E , Martiny Jennifer B H
Published: December 2012

Although microorganisms largely drive many ecosystem processes, the relationship between microbial composition and their functioning remains unclear. To tease apart the effects of composition and the environment directly, microbial composition must be manipulated and maintained, ideally in a natural ecosystem. In this study, we aimed to test whether variability in microbial composition affects functional processes in a field setting, by reciprocally transplanting riverbed sediments between low- and high-salinity locations along the Nonesuch River (Maine, USA). We placed the sediments into microbial ‘cages’ to prevent the migration of microorganisms, while allowing the sediments to experience the abiotic conditions of the surroundings. We performed two experiments, short- (1 week) and long-term (7 weeks) reciprocal transplants, after which we assayed a variety of functional processes in the cages. In both experiments, we examined the composition of bacteria generally (targeting the 16S rDNA gene) and sulfate-reducing bacteria (SRB) specifically (targeting the dsrAB gene) using terminal restriction fragment length polymorphism (T-RFLP). In the short-term experiment, sediment processes (CO2 production, CH4 flux, nitrification and enzyme activities) depended on both the sediment’s origin (reflecting differences in microbial composition between salt and freshwater sediments) and the surrounding environment. In the long-term experiment, general bacterial composition (but not SRB composition) shifted in response to their new environment, and this composition was significantly correlated with sediment functioning. Further, sediment origin had a diminished effect, relative to the short-term experiment, on sediment processes. Overall, this study provides direct evidence that microbial composition directly affects functional processes in these sediments.
A nonlinear Schrödinger equation for water waves on finite depth with constant vorticity
Authors: Thomas R. , Kharif C. , Manna M.
Published: December 2012

A nonlinear Schrödinger equation for the envelope of two dimensional surface water waves on finite depth with non-zero constant vorticity is derived, and the influence of this constant vorticity on the well-known stability properties of weakly nonlinear wave packets is studied. It is demonstrated that vorticity modifies significantly the modulational instability properties of weakly nonlinear plane waves, namely the growth rate and bandwidth. At third order, we have shown the importance of the nonlinear coupling between the mean flow induced by the modulation and the vorticity. Furthermore, it is shown that these plane wave solutions may be linearly stable to modulational instability for an opposite shear current independently of the dimensionless parameter kh, where k and h are the carrier wavenumber and depth, respectively.
Visual and dynamical measurement of Rayleigh-Benard convection by using fiber-based digital holographic interferometry
Authors: Wang Jun , Zhao Jianlin , Di Jianglei , Jiang Yajun , Rauf Abdul , Jiang Hongzhen
Published: December 2012

We present a method for visual and dynamical measurement of the Rayleigh-Benard convection by using fiber-based digital holographic interferometry. A SM600 fiber with 4 μm core diameter is used instead of conventional pinhole, which has better performance to filter out the noises, effectively modify the structure of the optical path and relax the requirement of the laser performance (e.g., coherence length and beam uniformity). The experimental results show the development process of Rayleigh-Benard cell in the container. The corresponding Rayleigh number is 3.6. In the process, the temperature at the top and bottom plates is controlled at 295 K and 300 K, respectively. The measured temperature distribution and the number of Rayleigh-Benard cell are verified by using simulation and are in good agreement.
Extended dynamical density functional theory for colloidal mixtures with temperature gradients
Authors: Wittkowski Raphael , Löwen Hartmut , Brand Helmut R.
Published: December 2012

In the past decade, classical dynamical density functional theory (DDFT) has been developed and widely applied to the Brownian dynamics of interacting colloidal particles. One of the possible derivation routes of DDFT from the microscopic dynamics is via the Mori-Zwanzig-Forster projection operator technique with slowly varying variables such as the one-particle density. Here, we use the projection operator approach to extend DDFT into various directions: first, we generalize DDFT toward mixtures of n different species of spherical colloidal particles. We show that there are in general nontrivial cross-coupling terms between the concentration fields and specify them explicitly for colloidal mixtures with pairwise hydrodynamic interactions. Second, we treat the internal energy density as an additional slow variable and derive formal expressions for an extended DDFT containing also the internal energy density. The latter approach can in principle be applied to colloidal dynamics in a nonzero temperature gradient. For the case without hydrodynamic interactions the diffusion tensor is diagonal, while thermodiffusion – the dissipative cross-coupling term between internal energy density and concentration – is nonzero in this limit. With finite hydrodynamic interactions also cross-diffusion coefficients assume a finite value. We demonstrate that our results for the extended DDFT contain the transport coefficients in the hydrodynamic limit (long wavelengths, low frequencies) as a special case.
Reaction pathways by quantum Monte Carlo: Insight on the torsion barrier of 1,3-butadiene, and the conrotatory ring opening of cyclobutene
Authors: Barborini Matteo , Guidoni Leonardo
Published: December 2012

Quantum Monte Carlo (QMC) methods are used to investigate the intramolecular reaction pathways of 1,3-butadiene. The ground state geometries of the three conformers s-trans, s-cis, and gauche, as well as the cyclobutene structure are fully optimised at the variational Monte Carlo (VMC) level, obtaining an excellent agreement with the experimental results and other quantum chemistry high level calculations. Transition state geometries are also estimated at the VMC level for the s-trans to gauche torsion barrier of 1,3-butadiene and for the conrotatory ring opening of cyclobutene to the gauche-1,3-butadiene conformer. The energies of the conformers and the reaction barriers are calculated at both variational and diffusional Monte Carlo levels providing a precise picture of the potential energy surface of 1,3-butadiene and supporting one of the two model profiles recently obtained by Raman spectroscopy [Boopalachandran et al., J. Phys. Chem. A 115, 8920 (2011)10.1021/jp2051596]. Considering the good scaling of QMC techniques with the system's size, our results also demonstrate how variational Monte Carlo calculations can be applied in the future to properly investigate the reaction pathways of large and correlated molecular systems.
IR spectroscopy of monohydrated tryptamine cation: Rearrangement of the intermolecular hydrogen bond induced by photoionization
Authors: Sakota Kenji , Kouno Yuuki , Harada Satoshi , Miyazaki Mitsuhiko , Fujii Masaaki , Sekiya Hiroshi
Published: December 2012

Rearrangement of intermolecular hydrogen bond in a monohydrated tryptamine cation, [TRA(H2O)1]+, has been investigated in the gas phase by IR spectroscopy and quantum chemical calculations. In the S0 state of TRA(H2O)1, a water molecule is hydrogen-bonded to the N atom of the amino group of a flexible ethylamine side chain [T. S. Zwier, J. Phys. Chem. A 105, 8827 (2001)10.1021/jp011659+]. A remarkable change in the hydrogen-bonding motif of [TRA(H2O)]+ occurs upon photoionization. In the D0 state of [TRA(H2O)1]+, the water molecule is hydrogen-bonded to the NH group of the indole ring of TRA+, indicating that the water molecule transfers from the amino group to NH group. Quantum chemical calculations are performed to investigate the pathway of the water transfer. Two potential energy barriers emerge in [TRA(H2O)1]+ along the intrinsic reaction coordinate of the water transfer. The water transfer event observed in [TRA(H2O)1]+ is not an elementary but a complex process.
A finite difference method for estimating second order parameter sensitivities of discrete stochastic chemical reaction networks
Authors: Wolf Elizabeth Skubak , Anderson David F.
Published: December 2012

We present an efficient finite difference method for the approximation of second derivatives, with respect to system parameters, of expectations for a class of discrete stochastic chemical reaction networks. The method uses a coupling of the perturbed processes that yields a much lower variance than existing methods, thereby drastically lowering the computational complexity required to solve a given problem. Further, the method is simple to implement and will also prove useful in any setting in which continuous time Markov chains are used to model dynamics, such as population processes. We expect the new method to be useful in the context of optimization algorithms that require knowledge of the Hessian.
Limitations of STIRAP-like population transfer in extended systems: The three-level system embedded in a web of background states
Authors: Jakubetz Werner
Published: December 2012

This paper presents a systematic numerical investigation of background state participation in STIRAP (stimulated Raman-adiabatic passage) population transfer among vibrational states, focusing on the consequences for the robustness of the method. The simulations, which are performed over extended grids in the parameter space of the Stokes- and pump pulses (frequencies, field strengths, and pulse lengths), involve hierarchies of (3 + N)-level systems of increasing complexity, ranging from the standard three-level STIRAP setup, (N = 0) in Λ-configuration, up to N = 446. A strongly coupled three-level core system is selected from the full Hamiltonian of the double-well HCN/HNC system, and the couplings connecting this core system to the remaining states are (re-) parameterized in different ways, from very weak to very strong. The systems so obtained represent a three-level system embedded in various ways in webs of cross-linked vibrational background states and incorporate typical molecular properties. We first summarize essential properties of population transfer in the standard three-level system and quantify the robustness of the method and its dependence on the pulse parameters. Against these reference results, we present results obtained for four (3 + 446)-level systems and several subsystems. For pulse lengths of at most few picoseconds the intrinsic robustness of STIRAP with respect to variations in the field strength disappears as soon as the largest core-background couplings exceed about one tenth of the STIRAP couplings. In such cases robustness with respect to variations in the field strength is entirely lost, since at higher field strengths, except for irregularly spaced narrow frequency ranges, transfer probabilities are strongly reduced. STIRAP-like population transfer is maintained, with some restrictions, at low field strengths near the onset of adiabatic transfer. The suppression of STIRAP is traced back to different mechanisms based on a plentitude of single- and multiphoton transitions to background states, which at the high field strengths characteristic for STIRAP proceed readily even along weakly coupled pathways.
Male traits and herd reproductive capability in tropical beef cattle. 2. Genetic parameters of bull traits
Authors: Corbet N. J. , Burns B. M. , Johnston D. J. , Wolcott M. L. , Corbet D. H. , Venus B. K. , Li Y. , McGowan M. R. , Holroyd R. G.
Published: December 2012

A total of 4063 young bulls of two tropical genotypes (1639 Brahman and 2424 Tropical Composite) raised in northern Australia were evaluated for a comprehensive range of production and reproduction traits up to 24 months of age. Prior to weaning, peripheral blood concentrations of luteinising hormone (LH) and inhibin were measured at 4 months of age. At weaning (6 months) blood insulin-like growth factor-1 (IGF-I) and flight time were recorded. Body composition traits of fat depth and eye-muscle area were determined by ultrasonography at 15 months of age when additional measurements of liveweight, hip height and body condition score were recorded. Bull breeding soundness was evaluated at ~12, 18 and 24 months of age when measurements of scrotal circumference, sheath score, semen mass activity, progressive motility of individual sperm and percent morphologically normal sperm were recorded. Magnitude of heritability and genetic correlations changed across time for some traits. Heritability of LH, inhibin, IGF-I and of 18-month scrotal circumference, mass activity, progressive motility and percent normal sperm was 0.31, 0.74, 0.44, 0.75, 0.24, 0.15 and 0.25, respectively, for Brahmans and 0.48, 0.72, 0.36, 0.43, 0.13, 0.15 and 0.20, respectively, for Tropical Composites. Inhibin and IGF-I had moderate genetic association with percent normal sperm at 24 months in Brahmans but low to negligible associations in Tropical Composites. Body condition score in Brahmans and sperm motility (mass and individual) traits in both genotypes had moderate to strong genetic correlation with percent normal sperm and may prove useful candidates for indirect selection. There is scope to increase scrotal circumference by selection and this will be associated with favourable correlated responses of improved semen quality in both genotypes. The lack of genetic antagonism among bull traits indicates that selection for improved semen quality will not adversely affect other production traits.
Discrete and Polymeric Cu(II) Coordination Complexes with a Flexible bis-(pyridylpyrazole) Ligand: Structural Diversity and Unexpected Solvothermal Reactivity
Authors: Hawes Chris S. , Kruger Paul E.
Published: December 2012

Reported here is the synthesis and structural characterisation of five copper complexes derived from the bis-bidentate ligand 4,4′-methylenebis(1-(2-pyridyl)-3,5-dimethylpyrazole), L. Complex 1, [Cu2L(CH3COO)4(OH2)2]·6H2O, is a single stranded unsaturated helical species that forms a highly connected three-dimensional hydrogen-bonding network, whereas [Cu2L(NO3)4], 2, is a coordination polymer derived from [Cu2L] fragments linked together via bridging nitrate anions to yield undulating two-dimensional sheets with (6,3)-topology. Complexes 3, 4, and 5 co-crystallise within a single batch when L is reacted under solvothermal conditions with Cu(NO3)2·2.5H2O in acetonitrile, and each contains a co-ligand formed by either decomposition of the solvent or ligand. Complex 3, [Cu4(NO3)4(µ-CH3COO)2(µ-OH)2L2], forms an unusual discrete cyclic tetrameric species containing acetate co-ligands derived through acetonitrile hydrolysis; whereas complex 4, [CuL(C2O4)(NO3)], forms a one-dimensional coordination polymer containing bridging oxalate co-ligands, formed through hydrolysis and oxidation of acetonitrile. Complex 5, [Cu2L(µ-CN)2], is a two-dimensional coordination polymer with (6,3) topology where bridging between Cu(i) centres is furnished by cyanide co-ligands, suggesting a ligand decomposition pathway for its origin, and produced with concomitant reduction of the Cu(ii) starting reagent. Having initially obtained 3, 4, and 5 serendipitously each were then prepared as pure phases by careful adjustment and control of the reaction conditions (reactant stoichiometry, concentrations, and solvothermal temperature), details of which are discussed.
Correlates of Modus Operandi (Coercion and Force) Among Male Sexually Victimized Adolescent Sexual Abusers: An Exploratory Study
Authors: LEIBOWITZ GEORGE
Published: December 2012

Researchers have noted that there are few empirical investigations on the factors associated with adolescent sexual abusers’ modus operandi (MO) (i.e., strategies used to coerce and/or force victim compliance). Understanding MO is critical for effective prevention and treatment. The extant literature has found that certain developmental experiences and contextual factors, such as a history of victimization and family characteristics, may be related to the use of specific MO strategies. New to the literature, this present study also investigated the relationship between substance abuse and MO. Physical neglect and being told by a third person to sexually abuse someone significantly predicted the severity of MO of male incarcerated adolescent sexually victimized sexual offenders (N = 148). Other forms of trauma and substance abuse were not predictors of MO. Research and treatment implications for forensic social workers are discussed.
A Theory of African American Offending: Race, Racism, and Crime by JAmes D. Unnever and Shaun L. Gabbidon
Authors: Kindle Peter A.
Published: December 2012

A Book Review
Intrinsic volumes and linear contractions
Authors: Paouris Grigoris , Pivovarov Peter
Published: December 2012

It is shown that intrinsic volumes of a convex body decrease under linear contractions.
Non-micro-short RNAs: the new kids on the block
Authors: Dey Bijan K. , Mueller Adam C. , Dutta Anindya
Published: December 2012

The advent of ultra–high-throughput sequencing has led to the discovery of a large group of small, noncoding RNAs that are not microRNAs. The functional relevance of microRNAs has been well established over the last decade. In this Perspective, we focus on the non-micro-short RNAs that comprise a variety of functional classes and range from 16–40 nucleotides in size. We will highlight how some of these non-micro-short RNAs were discovered, as well as their biogenesis, potential mechanisms of action, and role in diverse biological processes, development, and disease. Finally, we will describe what must be done to further our understanding of these enigmatic molecules.
Diagnosis and Management of Prosthetic Joint Infection: Clinical Practice Guidelines by the Infectious Diseases Society of Americaa
Authors: Osmon Douglas R. , Berbari Elie F. , Berendt Anthony R. , Lew Daniel , Zimmerli Werner , Steckelberg James M. , Rao Nalini , Hanssen Arlen , Wilson Walter R.
Published: December 2012

These guidelines are intended for use by infectious disease specialists, orthopedists, and other healthcare professionals who care for patients with prosthetic joint infection (PJI). They include evidence-based and opinion-based recommendations for the diagnosis and management of patients with PJI treated with debridement and retention of the prosthesis, resection arthroplasty with or without subsequent staged reimplantation, 1-stage reimplantation, and amputation.
Fatty acid‐binding protein 4 and incident heart failure: the Cardiovascular Health Study
Authors: Djoussé Luc , Bartz Traci M. , Ix Joachim H. , Kochar Jinesh , Kizer Jorge R. , Gottdiener John S. , Tracy Russell P. , Mozaffarian Dariush , Siscovick David S. , Mukamal Kenneth J. , Zieman Susan J.
Published: December 2012

Aim

To examine the association of plasma fatty acid‐binding protein 4 (FABP4) with incident heart failure.

Methods and results

In a prospective study of 4179 participants from the Cardiovascular Health Study, we measured plasma FABP4 on blood specimens collected between 1992 and 1993. Incident heart failure was adjudicated by an endpoint committee and we used a Cox proportional hazards model to calculate hazard ratios (HRs) of heart failure. The average age at baseline was 75 years. During a median follow‐up of 10.7 years, 1182 cases of incident heart failure occurred. We observed a positive association between FABP4 and heart failure in the minimally adjusted models [HR 1.32, 95% confidence interval (CI) 1.25–1.38 per 1 SD higher FABP4] that was attenuated upon adjustment for potential confounders, mostly kidney function and body mass index (corresponding HR 1.09, 95% CI 1.01–1.17). In a subsample of heart failure cases with available data on LV systolic function, FABP4 was not associated with heart failure with or without preserved LV systolic function. Exclusion of people with unintentional weight loss and self‐reported fair/poor health status did not alter the conclusion.

Conclusion

An elevated plasma concentration of FABP4 was associated with a modestly higher risk of heart failure in older adults in the USA after adjustment for confounding factors.
Neuropathogenesis of a mouse-adapted porcine epidemic diarrhea virus infection in suckling mice
Authors: Kotani Osamu , Shirato Kazuya , Nagata Noriyo , Ikeda Hidetoshi , Takahashi Kimimasa , Taguchi Fumihiro
Published: December 2012

A mouse-adapted porcine epidemic diarrhea virus, MK-p10, showed higher neurovirulence in suckling mice than a non-adapted MK strain. There was no difference in virus growth, whereas clear differences between these two virus infections existed in the type of target cells infected, the spread of virus and the cytokine levels produced in the brain. In the early phase of infection, neurons, astrocytes and neural progenitor cells were infected by MK-p10, whereas neural progenitor cells were the only target cells infected by MK. On days 4–5 post-inoculation, MK-p10 antigens were distributed in a number of neurons in a wide area of the brain; however, antigens were restricted in MK infection. In moribund mice in both infection groups, viral antigens were found in a wide area of the brain. The wide spectrum of initial target cells following MK-p10 infection, as well as its faster spread in the brain, may be evidence of enhanced virulence in suckling mice.
Does the Panoramic Radiography Have the Power to Identify the Gonial Angle in Orthodontics?
Authors: Okşayan Rıdvan , Aktan Ali Murat , Sökücü Oral , Haştar Esin , Ciftci Mehmet Ertuğrul
Published: December 2012

Purpose. The objective of this study was to assess gonial angle under the angle classification by comparing panoramic radiograph and lateral cephalometric radiograph.Materials and Methods. 49 patients (25 males, 24 females) with an age range of 12–29 years participated in the present study. Subjects were retrospectively selected among those categorised as skeletal and dental Class I, II, and III malocclusion group. Using lateral cephalometric radiograph, mandibular and ramal planes were drawn and based on these planes. Gonial angle was determined from two tangents which were drawn from the inferior border of the mandible and posterior borders of the condyle and ramus of both sides in the panoramic radiographs. Multiple comparison tests (ANOVA) were used to determine differences between the three angle groups.Results. There were no significant differences between Class I, II, and III malocclusion group values of gonial angles determined by lateral cephalometric radiograph and panoramic radiographs ().Conclusion. Panoramic radiograph results were shown to be as reliable as lateral cephalometric radiograph in all angle classifications. Panoramic radiography can be used as an alternative radiographic technique to detect gonial angle in orthodontic patients.