bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Long‐Range 1H‐15N Heteronuclear Shift Correlation Data on Computer‐Assisted Structure Elucidation: Posaconazole
Authors: Hilton Bruce D. , Martin Gary E.
Published: July 2012

Considerable work has been invested in the area of computer‐assisted structure elucidation (CASE) methods. As NMR techniques have been developed that provide more effective atom‐to‐atom connectivity information, it has become theoretically possible to do de novo structure elucidation based on 2D NMR datasets recorded for an unknown molecule. However, as annular (ring) nitrogen atoms become more prevalent in complex chemical structures, the ability to rely solely on 1H and 13C homo‐ and hetero‐nuclear direct and long‐range connectivity information to solve a structure correspondingly diminishes. Hence, we now wish to report the results of an investigation into the application of CASE methods with and without long‐range 1H‐15N data using posaconazole as a model compound, which has eight annular nitrogens in its structure. With the inclusion of 1H‐15N data long‐range data, the structure could be successfully determined in a few hours. Excluding the 1H‐15N data caused the program to generate millions of candidate structures, none of which fit the data well enough to be stored.
The Divergent Transformations of Aromatic o‐Aminonitrile with Carbonyl Compound
Authors: Tang Jianhong , Li Jiarong , Zhang Lijun , Ma Shuling , Shi Daxin , Zhang Qi , Yang Liupan , Wang Xiuzhen , Liu Xuan , Liu Change
Published: July 2012

A modified Friedländer conversion of the cyclocondensation of aromatic o‐aminonitriles with carbonyl compounds was discovered. Systematic studies reveal that both the new transformation and the classic Friedländer annulation in the presence of ZnCl2 constitute a pair of divergent reaction, and thecontrolled PDF transformation of this divergent reaction was achieved in the present of bases.
2,2‐Bis(methoxy‐NNO‐azoxy)ethyl Derivatives of 4,8‐Dihydro‐bis‐furazano[3,4‐b:3′4′‐e]pyrazine: The Synthesis and X‐ray Investigation
Authors: Zyuzin Igor N. , Suponitsky Kyrill Yu. , Sheremetev Aleksei B.
Published: July 2012

The first synthesis of 4,8‐dihydro‐bis‐furazano[3,4‐b:3′4′‐e]pyrazine bearing 2,2‐bis(methoxy‐NNO‐azoxy)ethyl groups has been developed. These compounds are obtained by aza‐Michael reaction of 1,1‐bis(methoxy‐NNO‐azoxy)ethene or its equivalents, such as 2,2‐bis(methoxy‐NNO‐azoxy)ethanol derivatives, with 4,8‐dihydro‐bis‐furazano[3,4‐b:3′4′‐e]pyrazine.
A Simple, Convenient, and Efficient Synthetic Route for The Preparation of (Z)‐3,5‐Dichloro‐N‐(3‐(4‐substitutedphenyl)‐4‐phenylthiazole‐2(3H)‐ylide)benzamide Heterocyclic Compounds from Aroyl Thiourea Derivatives via S‐cyclization Mechanism
Authors: Saeed Sohail , Wong Wing‐Tak
Published: July 2012

A series of variously substituted 1,3‐thiazole heterocyclic compounds (3a–3d) were prepared by base‐catalyzed S‐cyclization of corresponding 2,4‐dichloro‐N‐{[(4‐substitutedphenyl)amino]carbonothioyl}benzamide (2a–2d) with acetophenone in the presence of bromine. The structure of all compounds was established by IR, 1H‐NMR, 13C‐NMR, elemental analysis, and X‐ray crystallographic analysis.
Studies on Reactive Pyridylketones Formed by Weinreb Transformations
Authors: Stockmann Vegar , Kaspersen Svein Jacob , Nicolaisen Alexander , Fiksdahl Anne
Published: July 2012

A method has been developed to allow the preparation of reactive pure vinylpyridylketones and activated vinylketones, in general, to be used in further reactions, such as cycloadditions. The process is based on the Weinreb's amide transformation and includes a quarternary ammonium intermediate and subsequent elimination. Additionally, based on our previous results on the malonate alkylation of 3‐nitropyridines and subsequent synthetic applications, we present the studies on the transformation of pyridyl malonate derivative 3 via the Weinreb's amide 4 and reactive methylpyridyl‐ (17) and allylpyridyl‐ketone (6) into bis‐heterocyclic products 18 and 19, and 8, 20, and 21, respectively.
Synthesis of 1,2,3‐Triazole Substituted Isoxazoles via Copper (I) Catalyzed Cycloaddition
Authors: Ramana P. Venkata , Reddy A. Ram
Published: July 2012

The synthesis of a series of 3,5‐disubstituted isoxazole‐4‐carboxylic esters containing N‐substituted 1,2,3‐triazoles (V) starting from various benzaldehydes (I) is reported. Benzaldehydes undergo oximation with hydroxylamine hydrosulfate. Later, chlorination followed by condensation with methylacetoacetate and the hydrolysis of the resulting ester afforded respective carboxylic acid (II), which on chlorination with PCl5 gave the corresponding acid chlorides (III). The coraboxylic acid chlorides (III) on propargylation gave propargylic esters (IV) and these on click reaction gave the title compounds (V).
Synthesis and Characterization of Novel Ionic Liquids: N‐Substituted Aziridinium Salts
Authors: Duriska Martin B. , Grondin Joseph , Servant Laurent , Birot Marc , Deleuze Hervé
Published: July 2012

Ionic liquids based on three‐membered ring aziridinium cations have been synthesized for the first time using a straightforward synthetic route. N‐butyl‐N‐methylaziridinium bis(trifluoromethanesulfonyl)imide, N‐propyl‐N‐ethylaziridinium bis(trifluoromethanesulfonyl)imide, N‐butyl‐N‐[2‐(2‐methoxyethoxy)ethyl]aziridinium bis(trifluoromethanesulfonyl)imide, N‐butyl‐N‐methylaziridinium dicyanamide, and N‐butyl‐N‐ethylaziridinium dicyanamide were thus obtained in good yields and satisfactory purity and fully characterized.
Development of a hospitalist‐led‐and‐directed physical examination curriculum
Authors: Janjigian Michael P. , Charap Mitchell , Kalet Adina
Published: July 2012

BACKGROUND: Deficiencies in physical examination skills among medical students, housestaff, and even faculty have been reported for decades, though specifics on how to address this deficit are lacking.

METHODS: Our institution has made a commitment to improving key physical examination competencies across our general medicine faculty. Development of the Merrin Bedside Teaching Program was guided by a comprehensive needs assessment and based on a learner‐centered educational model. First, selected faculty fellows achieve expertise through mentorship with a master clinician. They then develop a bedside teaching curriculum in the selected domain and conclude by delivering the curriculum to peer faculty.

RESULTS: We have developed curricula in examination of the heart, shoulder, knee, and skin. Currently, curricula are being developed in the examination of the lungs, critical care bedside rounds, and motivational interviewing. Curricula are integrated with educational activities of the internal medicine residency and medical school whenever possible.

CONCLUSIONS: A hospitalist‐led physical examination curriculum is an innovative way to address deficits in physical exam skills at all levels of training, engenders enthusiasm for skills development from faculty and learners, offers scholarship opportunities to general medicine faculty, encourages collaboration within and between institutions, and augments the education of residents and medical students. Journal of Hospital Medicine 2012. © 2012 Society of Hospital Medicine.
The moderating effects of job control and selection, optimization, and compensation strategies on the age–work ability relationship
Authors: Weigl Matthias , Müller Andreas , Hornung Severin , Zacher Hannes , Angerer Peter
Published: July 2012

Work ability describes employees' capability to carry out their work with respect to physical and psychological job demands. This study investigated direct and interactive effects of age, job control, and the use of successful aging strategies called selection, optimization, and compensation (SOC) in predicting work ability. We assessed SOC strategies and job control by using employee self‐reports, and we measured employees' work ability using supervisor ratings. Data collected from 173 health‐care employees showed that job control was positively associated with work ability. Additionally, we found a three‐way interaction effect of age, job control, and use of SOC strategies on work ability. Specifically, the negative relationship between age and work ability was weakest for employees with high job control and high use of SOC strategies. These results suggest that the use of successful aging strategies and enhanced control at work are conducive to maintaining the work ability of aging employees. We discuss theoretical and practical implications regarding the beneficial role of the use of SOC strategies utilized by older employees and enhanced contextual resources at work for aging employees. Copyright © 2012 John Wiley & Sons, Ltd.
Timing and level of nitrogen supply affect nitrogen distribution and recovery in two contrasting oat genotypes
Authors: Zhao Gui‐Qin , Ma Bao‐Luo , Ren Chang‐Zhong , Liang Bao‐Chang
Published: July 2012

Human diets containing oat (Avena sativa L.) grain offer health benefits resulting in an emerging interest in oat improvement. Information on nitrogen (N) uptake, distribution, and use efficiency (NUE) in oat is limited. A greenhouse study using a 15N‐labeling technique was conducted to determine the responses of two contrasting oat genotypes to timing and level of N deficiency. Hulled oat cv. Prescott and hulless cv. AC Gehl were grown in soil‐mix pot culture with five N treatments applied through modified Hoagland solutions. Differences in 15N accumulation, 15N distribution, plant N originating from the labeled source, and NUE between the contrasting cultivars, were examined for each N strategy. Level of N deficiency and timing of N supply of 15NH415NO3 greatly affected 15N distribution, the origins of plant N, and the amount of 15N recovered in the plant. When N was supplied from seedling emergence to maturity (T1), AC Gehl accumulated 61% more 15N in the shoots, but 46% less 15N in the grain than Prescott (0.43 vs. 0.80 mg plant–1), indicating that AC Gehl was less effective in producing grain yield than Prescott as AC Gehl produced greater total dry matter (DM). Withholding N supply until flag‐leaf stage (FL) increased 15N in the grain of both cultivars by 29.6%, resulting in the highest NUE. In most cases, there were larger portions of plant N derived from the labeled source for AC Gehl than for Prescott. Our results suggest that greater NUE in the newly released AC Gehl was associated with N accumulation in the vegetative tissues. It is concluded that genotype improvement of hulless oat should be focused on enhancing N‐translocation efficiency.
Raman investigations on marker pen inks
Authors: Sodo A. , Bicchieri M. , Guiso M. , Ricci M. A. , Ricci G.
Published: July 2012

Characterization and conservation of materials used in contemporary art are a big challenge for scientists and restorers because of the huge variability and the large heterogeneity of their use and compositions. The aim of this work is to contribute to the knowledge of the composition of new materials extensively applied in contemporary artworks, namely the marker pen inks. Marker pen inks represent a serious problem for restorers as they fade in a few years, changing colour and shade. Moreover, they are often soluble in the commonly used solvents. This research is performed in collaboration with the Fondazione Federico Fellini, owner of more than 500 original drawings of the famous movie director – most of them realised by marker pens. In this work, we report, for the first time, Raman spectra of marker pen original and ‘laboratory’ drawings. Studies of the ‘laboratory’ samples have been complemented by thin layer chromatography in order to separate the complex colouring mixture into its individual components. Raman spectra of yellow, orange and red standard samples of two consumer and two professional brands have been recorded and identified. A comparison among old and new marker pen inks composition is discussed, and inferences are drawn about the brand likely used in the two originals. Interestingly, we notice that food additives are often used as colour agents in marker pen inks and report here their standard Raman spectra. This study puts into evidence the need for a reliable standard database of pigments and dyes. Copyright © 2012 John Wiley & Sons, Ltd.
The influence of the final cause doctrine on anatomists of the sixteenth and seventeenth centuries concerning selected anatomical structures of the head and neck
Authors: Lydiatt Daniel D. , Bucher Gregory S.
Published: July 2012

The Doctrine of Final Cause, taken from Aristotle's “causes” and modified by Claudius (Aelius) Galen (of Pergamon) stated that for an anatomical part to exist it must have a “cause,” not an end point, but a purpose or goal, natural or divine. This affected the renaissance anatomist's thinking. We explore this doctrine's relationship with human head and neck anatomy from antiquity's Aristotle and Galen, and the leading renaissance anatomists from the 16th and 17th centuries. Their relevant writings were influenced by religious and political beliefs and varied from humanistic to reactionary.

Tracing anatomical controversies through these works reveal the humanism of Vesalius and others as paralleling the humanists of art and literature. These controversies illustrate how the body was used to demonstrate function, uses, and causes from higher sources. Humanists advanced the social, philosophical, intellectual, literary, and medical/anatomical thoughts of this period. They stood between the Christian church of the Middle Ages and modern science.

Like religion, medicine and anatomy had its own revealed sources of knowledge and had sacred texts like Galen's. Vesalius' the Fabrica and the woodcuts established suddenly the beginning of modern observational science and art as the direct and faithful representation of natural phenomena. They displayed anatomy such that others could understand, including errors of Galen, bringing Vesalius into ecclesiastical conflict. Evolutionary scientists today see mutations as favorable or unfavorable depending on the environment. Mutations are random or directed by divine plan, according to perspectives of this ancient debate. Laryngoscope, 2012
On extensions and restrictions of semigroups of linear operators in a Banach space and their applications
Authors: Gorbachuk M. , Gorbachuk V.
Published: July 2012

The description of all solutions on (0, ∞) of differential equations of parabolic and elliptic type in a Banach space is given without imposing any conditions on their behavior near the point 0, and the properties of them are studied. The necessary and sufficient conditions on the initial data, under which the Cauchy problem for a general operator‐differential equation is solvable in the class of locally analytic, entire or entire of finite order and finite type vector‐valued functions, are established. The results are based on the theory of restrictions and extensions of analytic semigroups set forth below.
On the syzygies and Alexander polynomials of nodal hypersurfaces
Authors: Dimca Alexandru , Sticlaru Gabriel
Published: July 2012

We give sharp lower bounds for the degree of the syzygies involving the partial derivatives of a homogeneous polynomial defining a nodal hypersurface. The result gives information on the position of the singularities of a nodal hypersurface expressed in terms of defects or superabundances.

The case of Chebyshev hypersurfaces is considered as a test for this result and leads to a potentially infinite family of nodal hypersurfaces having nontrivial Alexander polynomials.
Toward online reconstruction of quantitative susceptibility maps: Superfast dipole inversion
Authors: Schweser Ferdinand , Deistung Andreas , Sommer Karsten , Reichenbach Jürgen Rainer
Published: July 2012

Magnetic susceptibility is an intrinsic tissue property that recently became measureable in vivo by a magnetic‐resonance based technique called quantitative susceptibility mapping (QSM). Although QSM may be performed without additional acquisition time, for example, in the course of the well‐established susceptibility weighted imaging, the applicability of QSM is currently hampered by the numerical complexity and computational cost associated with the reconstruction procedure. This work introduces a novel QSM framework called superfast dipole inversion which allows rapid online reconstruction of susceptibility maps from wrapped raw gradient‐echo phase data. The algorithm relies on the extension and combination of several recent algorithms involving the precalculation of convolution kernels and the correction of inversion artifacts. Reconstruction of three‐dimensional high resolution susceptibility maps of the human brain was achieved with superfast dipole inversion in less than 20 s on a conventional workstation computer. Thus, superfast dipole inversion opens the door to an implementation of QSM on MR scanner hardware as well as to the routine reconstruction of large cohorts of datasets. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Three‐dimensional integration strategies of singular functions introduced by the XFEM in the LEFM
Authors: Minnebo Hans
Published: July 2012

The use of the extended finite element method in the scope of linear elastic fracture mechanics induces the integration of singular functions in terms of the stiffness matrix and in the computation of stress intensity factors using the interaction integral method. An adapted method is proposed in this paper to treat efficiently the three‐dimensional case. The improvement is demonstrated by comparison with standard and other methods found in the literature. Copyright © 2012 John Wiley & Sons, Ltd.
The bipenalty method for arbitrary multipoint constraints
Authors: Hetherington Jack , Rodríguez‐Ferran Antonio , Askes Harm
Published: July 2012

In finite element (FE) analysis, traditional penalty methods impose constraints by adding virtual stiffness to the FE system. In dynamics, this can decrease the critical time step of the system when conditionally stable time integration schemes are used by introducing spurious modes with high eigenfrequencies. Recent studies have shown that using mass penalties alongside traditional stiffness penalties can mitigate this effect for systems with a one single‐point constraint. In the present work, we extend this finding to include systems with an arbitrary set of multipoint constraints. By analysing the generalised eigenvalue problem, we show that the values of spurious eigenfrequencies may be controlled by the choice of stiffness and mass penalty parameters. The method is demonstrated using numerical examples, including a one‐dimensional contact–impact formulation and a two‐dimensional crack propagation analysis. The results show that constraint imposition using the bipenalty method can be employed such that the critical time step of an analysis is unaffected, whereas also displaying superiority over the mass penalty method in terms of accuracy and versatility. Copyright © 2012 John Wiley & Sons, Ltd.
Recalibration of the Large Scale Gap‐Test to a Stress Scale
Authors: Braithwaite Christopher H. , Pachman Jiri , Majzlik Jiri , Williamson David M.
Published: July 2012

A series of gap‐test experiments were conducted in accordance with the EMTAP Test 22a guidelines to characterize the stress output from a donor charge of ROWANEX 3601. Forty eight successful gap‐tests were conducted at the University of Pardubice in addition to two supporting plate impact experiments performed at the Cavendish Laboratory, University of Cambridge. The experiments indicated that there are two principal release mechanisms, which produce the observed reduction in stress with increasing gap distance. The first is attenuation of the input wave, something which is expected during explosive loading due to the triangular nature of the loading pulse. The second is an interaction between the input wave and lateral release waves from the edges of the test sample at the measurement station. Attenuation of the input wave due to visco‐elastic loss in the PMMA “gap” used is likely to be less significant than these other two release mechanisms. The data generated by this investigation forms a robust dataset that gives an accurate calibration for ROWANEX 3601 for users of the EMTAP 22a test procedure. In addition the data represent an excellent “set problem” for those developing and wishing to validate, computational models of similar physical phenomena.
POTENTIAL IMPACTS OF SMALL‐SCALE HYDROELECTRIC POWER GENERATION ON DOWNSTREAM MOVING LAMPREYS
Authors: Bracken F. S. A. , Lucas M. C.
Published: July 2012

Small‐scale hydropower is developing rapidly in many countries in response to policies of encouraging renewable energy and reducing reliance on fossil fuels. This rapid increase in the construction of hydroelectric turbines provides a substantial risk to migrating biota, especially fish. Some turbines, such as the Archimedes screw design, are regarded as relatively friendly to fish but have not yet been assessed for their potential impacts on threatened lamprey species. To assess the risk of impingement and the patterns of movement by emigrating river lamprey Lampetra fluviatilis transformers and drifting larval ammocoetes at the site of an Archimedes screw turbine in north‐east England, drift nets were set over the periods of January to June 2009 and November 2009 to May 2010. Drifting Lampetra sp. larvae were recorded in all sampling months, November to June, while emigrating lampreys were recorded in all months but June (93% captured between December and April), reflecting a higher period of impingement risk than expected. Night‐time catches were 24‐ and 8‐fold higher for transformers and larvae, respectively, than daytime catches. Catch per unit water volume data in different channel areas suggest that lamprey larvae behaved as passive particles within the river flow but that transformers selected areas of higher flow. Damage rates of lampreys passed through the screw were low (1.5%), suggesting minor impacts on downstream‐moving larval and juvenile lampreys. However, the cumulative potential impacts of multiple hydropower sites on downstream fish passage, including lampreys, should be considered by regulatory agencies when planning hydropower development within catchments. Copyright © 2012 John Wiley & Sons, Ltd.
A refined decompiler to generate C code with high readability
Authors: Chen Gengbiao , Qi Zhengwei , Huang Shiqiu , Ni Kangqi , Zheng Yudi , Binder Walter , Guan Haibing
Published: July 2012

As a key part of reverse engineering, decompilation plays a very important role in software security and maintenance. A number of tools, such as Boomerang and IDA Hex_rays, have been developed to translate executable programs into source code in a relatively high‐level language. Unfortunately, most existing decompilation tools suffer from low accuracy in identifying variables, functions, and composite structures, resulting in poor readability. To address these limitations, we present a practical decompiler called C‐Decompiler for Windows C programs that (i) uses a shadow stack to perform refined data flow analysis, (ii) adopts inter‐basic‐block register propagation to reduce redundant variables, and (iii) recognizes library (i.e., Standard Template Library) functions by signatures. We evaluate and compare the decompilation quality of C‐Decompiler with two existing tools, Boomerang and IDA Hex_rays, considering four aspects: function analysis, variable expansion rate, total percentage reduction, and cyclomatic complexity. Our experimental results show that on average, C‐Decompiler has the highest total percentage reduction of 55.91%, lowest variable expansion rate of 55.79%, and the same cyclomatic complexity as the original source code for each considered application. Furthermore, in our experiments, C‐Decompiler is able to recognize functions with a lower false positive and false negative rate than the other decompilers. A case study and our evaluation results confirm that C‐Decompiler is a practical tool to produce highly readable C‐style code. Copyright © 2012 John Wiley & Sons, Ltd.
Endogenous versus exogenous nutrient affects C, N, and P dynamics in decomposing litters in mid‐subtropical forests of China
Authors: Chen Fu‐Sheng , Feng Xue , Liang Chao
Published: July 2012

The effect of nutrient availability on litter decomposition has been a major focus of global change ecology. The relative impacts of endogenous (litter) and exogenous (soil) nutrient availability remain unclear. We studied the nutrient dynamics of decomposition in litter from two species with contrasting litter nutrient contents and stoichiometry: Pinus massoniana and Castanopsis sclerophylla. During a 540‐day field incubation, we manipulated exogenous nutrient levels by adding microbially available C (+C), N (+N), P (+P), and all three (+CNP) at 90‐day intervals. Relative to the no‐nutrient control (CK), nutrient additions decreased organic C retention in C. sclerophylla, with the greatest effect observed in +CNP. Nitrogen content in P. massoniana litter similarly increased with nutrient addition, particularly +P and +CNP. The P addition treatments also increased P content in the litter of both species. Nitrogen content in C. sclerophylla and organic C content in P. massoniana were unaffected by nutrient additions. The C/N and C/P ratios in decomposing C. sclerophylla litter were significantly lower in the CK treatment, while those of P. massoniana litter were influenced by the interaction of nutrient addition and decomposition time. Increased availability of C, N, and P individually and collectively alters nutrient release dynamics in decomposing foliar litter. Litter quality, as determined by source species, is a key determinant of the impact of exogenous nutrient inputs. A stronger effect of P addition than N addition indicates a relatively N‐rich and P‐poor ecosystem.
Evidence for nucleotide‐dependent processes in the thylakoid lumen of plant chloroplasts – an update
Authors: Spetea Cornelia , Lundin Björn
Published: July 2012

The thylakoid lumen is an aqueous chloroplast compartment enclosed by the thylakoid membrane network. Bioinformatic and proteomic studies indicated the existence of 80–90 thylakoid lumenal proteins in Arabidopsis thaliana, having photosynthetic, non‐photosynthetic or unclassified functions. None of the identified lumenal proteins had canonical nucleotide‐binding motifs. It was therefore suggested that, in contrast to the chloroplast stroma harboring nucleotide‐dependent enzymes and other proteins, the thylakoid lumen is a nucleotide‐free compartment. Based on recent findings, we provide here an updated view about the presence of nucleotides in the thylakoid lumen of plant chloroplasts, and their role in function and dynamics of photosynthetic complexes.
The age of camptonite dikes of the Agardag alkali-basalt complex (western Sangilen): results of Ar/Ar and U/Pb dating
Authors: Gibsher A.A. , Malkovets V.G. , Travin A.V. , Belousova E.A. , Sharygin V.V. , Konc Z.
Published: July 2012

A camptonite dike swarm (Agardag alkali-basalt complex) in the western part of the Sangilen Upland abounds in mantle xenoliths. Mineralogical, petrographic, and petrochemical studies show that the dikes are composed of lamprophyres of two groups, basic and ultrabasic. Ar/Ar dating of amphibole and phlogopite megacrysts gives an intrusion age for the dikes of 443.0 ± 1.3 Ma. 206Pb/238U dating of zircon from a glomeroporphyritic intergrowth in camptonite from one of the dikes yielded a core age of 489.0 ± 5.4 Ma. This corresponds to the time of formation of the Chzhargalanta granite–leucogranite complex (489.4 ± 2.6 Ma). The 206Pb/238U age of the zircon rim is 444.0 ± 7.5 Ma. The ages obtained by Ar/Ar dating of amphibole and biotite megacrysts and by U/Pb dating of the magmatic rim of zircon crystal from the camptonite coincide within the dating error, which indicates that the camptonite dikes formed in the Late Ordovician. These dikes are the oldest-known example of mantle-derived xenoliths in mafic volcanic rocks from an off-craton setting. These are samples of the Upper Ordovician lithospheric mantle.
Direct numerical simulation and biglobal stability investigations of the gaseous motion in solid rocket motors
Authors: Chedevergne F. , Casalis G. , Majdalani J.
Published: July 2012

In this article, a biglobal stability approach is used in conjunction with direct numerical simulation (DNS) to identify the instability mode coupling that may be responsible for triggering large thrust oscillations in segmented solid rocket motors (SRMs). These motors are idealized as long porous cylinders in which a Taylor–Culick type of motion may be engendered. In addition to the analytically available steady-state solution, a computed mean flow is obtained that is capable of securing all of the boundary conditions in this problem, most notably, the no-slip requirement at the chamber headwall. Two sets of unsteady simulations are performed, static and dynamic, in which the injection velocity at the chamber sidewall is either held fixed or permitted to vary with time. In these runs, both DNS and biglobal stability solutions converge in predicting the same modal dependence on the size of the domain. We find that increasing the chamber length gives rise to less stable eigenmodes. We also realize that introducing an eigenmode whose frequency is sufficiently spaced from the acoustic modes leads to a conventional linear evolution of disturbances that can be accurately predicted by the biglobal stability framework. While undergoing spatial amplification in the streamwise direction, these disturbances will tend to decay as time elapses so long as their temporal growth rate remains negative. By seeding the computations with the real part of a specific eigenfunction, the DNS outcome reproduces not only the imaginary part of the disturbance, but also the circular frequency and temporal growth rate associated with its eigenmode. For radial fluctuations in which the vorticoacoustic wave contribution is negligible in relation to the hydrodynamic stability part, excellent agreement between DNS and biglobal stability predictions is ubiquitously achieved. For axial fluctuations, however, the DNS velocity will match the corresponding stability eigenfunction only when properly augmented by the vorticoacoustic solution for axially travelling waves associated with the Taylor–Culick profile. This analytical approximation of the vorticoacoustic mode is found to be quite accurate, especially when modified using a viscous dissipation function that captures the decaying envelope of the inviscid acoustic wave amplitude. In contrast, pursuant to both static and dynamic test cases, we find that when the frequency of the introduced eigenmode falls close to (or crosses over) an acoustic mode, a nonlinear mechanism is triggered that leads to the emergence of a secondary eigenmode. Unlike the original eigenmode, the latter materializes naturally in the computed flow without being artificially seeded. This natural occurrence may be ascribed to a nonlinear modal interplay in the form of internal, eigenmode-to-eigenmode coupling instead of an external, eigenmode pairing with acoustic modes. As a result of these interactions, large amplitude oscillations are induced.
Use of Smoking Cessation Aids: Role of Perceived Safety and Efficacy
Authors: Ferguson Stuart G. , Schüz Benjamin , Gitchell Joe G.
Published: July 2012

The majority of smokers indicate that they would like to quit. It has been estimated that approximately three quarters of Australian smokers have tried to change their behaviour in the last 12 months (Scollo & Winstanley, 2008); similarly, more than half of US smokers report having tried to quit in the last year (Centers for Disease Control and Prevention [CDC], 2011). Despite their interest in quitting, the proportion of smokers who successfully quit each year is very low (CDC, 2011). While other factors are also important, poor cessation rates can partly be attributed to the low uptake of efficacious smoking cessation methods, particularly pharmacotherapies (Shiffman, Brockwell, Pillitteri, & Gitchell, 2008).
The Air Cure Town: Commodifying Mountain Air in Alpine Central Europe
Authors: Frank Alison F.
Published: July 2012

Does air have value? In the first volume ofCapital, Marx suggested it did not: “A thing can be a use-value, without having value,” he explained. “This is the case whenever its utility to man is not due to labour. Such are air, virgin soil, natural meadows, &c.” Because it has no value, understood by Marx in this context to mean labor value, air cannot be a commodity: “Commodities come into the world in the shape of use-values, articles, or goods, such as iron, linen, corn, &c. This is their plain, homely, bodily form. They are, however, commodities, only because they are something two fold, both object of utility, and, at the same time, depositories of value.” Marx's materialist focus on human labor and industrial production made it hard for him to imagine air as a commodity—at least when he published the first volume ofCapitalin 1867.
State Support for the German Cooperative Movement, 1860–1914
Authors: Guinnane Timothy W.
Published: July 2012

Germany's cooperative movement grew and thrived from its inception in the late 1840s to World War I and beyond. Cooperatives were divided along several lines, and perhaps the most serious point of contention concerned the role of the state in the movement. Cooperative leaders in the two decades before World War I especially debated whether they should accept direct grants and subsidized credit from theReichand theLänder. The several parts of the cooperative movement construed the question differently; much internecine conflict turned on the answers. The cooperative movement's historiography has largely framed the question as did Hermann Schulze-Delitzsch and other cooperative leaders opposed to state assistance. To him, the issue was whether cooperatives would be based on “self-help” or “state help.”
Don't Fence Me In: Barricade Sociality and Political Struggles in Mexico and Latvia
Authors: Dzenovska Dace , Arenas Iván
Published: July 2012

In 1991, barricades in the streets of Rīga, Latvia, shielded important landmarks from Soviet military units looking to prevent the dissolution of the USSR; in 2006, barricades in the streets of Oaxaca, Mexico, defended members of the Popular Assembly of the Peoples of Oaxaca from paramilitary incursions. We employ these two cases to compare the historically specific public socialities and politics formed through spatial and material practices in moments of crisis and in their aftermath. We show how the barricades continue to animate social and political formations and imaginaries, providing a sense of both past solidarity and future possibilities against which the present, including the state of the polity and the life of the people, are assessed. We trace the convergences and differences of political imaginaries of barricade sociality that formed in the barricades’ aftermath and consider what their transformative potential might be. Attentive to the specificity of particular practices and social relations that produce a collective subject, we consider how our case studies might inform broader questions about social collectives like the nation and publics. Though they point in different directions, we argue that the barricades provide an enabling position from which to imagine and organize collective life otherwise. In a moment when much mainstream political activism remains spellbound by the allure of discourses of democracy that promise power to the people, the Mexico and Latvia cases provide examples of social life that exceeded both state-based notions of collectives and what Michael Warner has called “state-based thinking,” even as they were also entangled with state-based frames.
Before Hegemony: Adam Smith, American Independence, and the Origins of the First Era of Globalization
Authors: Morrison James Ashley
Published: July 2012

While extensive scholarship has shown that it is possible to maintain global economic openness after hegemony, economic liberalization is still thought to be unlikely prior to hegemonic ascent. This assumption is based on the conventional narrative that Great Britain began lowering its trade barriers in the 1820s as it began its hegemonic ascent. This article shows that Britain began pursuing an open trading structure in the 1780s—in precisely the multipolar world that hegemonic stability theorists claimed would be least likely to initiate the shift. This change in commercial strategy depended crucially on the intellectual conversion of a key policymaker—the Earl of Shelburne—from mercantilist foreign economic policy to Adam Smith's revolutionary laissez-faire liberalism. Using the case of “the world's most important trading state” in the nineteenth century, this article highlights the importance of intellectuals—as well as their ideas—in shaping states' foreign policy strategies. It also provides further evidence of key individuals' significance and their decisions at “critical junctures.”
Design of a TRN Tracking Loop: a Study on GPS Multipath Mitigation Strategies
Authors: Vaman D. , Oonincx P.J.
Published: July 2012

Terrain Referenced Navigation (TRN) is based on the comparison of terrain altitude measurements with a reference map. Similar to code acquisition and tracking in Global Positioning System (GPS), the TRN system needs to find and track a particular sequence of measurements in a larger dataset. In our earlier work, these correspondences have been exploited to design a GPS inspired algorithm for TRN. The tracking loop is implemented as an early-late correlator, based on the DLL functional principle. Differences between GPS and terrain data in terms of signal properties are often based on the analysis of an ‘ideal’ GPS signal. In reality a GPS signal suffers from disturbances such as multipath and interference. This paper focuses on the identification and evaluation of potential GPS multipath mitigation strategies to be used to partly mitigate the issues caused by the non-ideal terrain signal. Results for the TRN implementations are described in a comparative manner. The content of this paper was presented during the European Navigation Conference 2011 in London.
Tularaemia seroprevalence of captured and wild animals in Germany: the fox (Vulpes vulpes) as a biological indicator
Authors: KUEHN A. , SCHULZE C. , KUTZER P. , PROBST C. , HLINAK A. , OCHS A. , GRUNOW R.
Published: July 2012

A total of 2475 animals from Germany, both captive and wild, were tested for antibodies againstFrancisella tularensisto obtain more knowledge about the presence of this pathogen in Germany. An indirect and a competitive ELISA served as screening methods, positive and inconclusive samples were confirmed by Western blot. Of the zoo animals sampled between 1992 and 2007 (n = 1122), three (0·3%) were seropositive. The seroconversion of a hippopotamus in Berlin Zoo was documented. From 1353 serum samples of wild foxes (Vulpes vulpes), raccoon dogs (Nyctereutes procyonoides) and wild boars (Sus scrofa), collected between 2005 and 2009 in the federal state of Brandenburg (surrounding Berlin), a total of 101 (7·5%) tested positive for antibodies toF. tularensislipopolysaccharide. Our results indicate a higher seroprevalence ofF.tularensisin wildlife in eastern Germany than commonly assumed. Furthermore, we found foxes and raccoon dogs to be biological indicators for tularaemia.
Precursor signatures and evolution of post‐sunset equatorial spread‐F observed over Sanya
Authors: Li Guozhu , Ning Baiqi , Abdu M. A. , Wan Weixing , Hu Lianhuan
Published: July 2012

Recent case studies on the precursor signatures of equatorial spread‐F (ESF) have shown a one‐to‐one correspondence between the large‐scale wave structures (LSWS) and ESF development at equatorial latitude. In this study, the LSWS and the onset and development of the ESF are investigated over Sanya (18°N, 109°E), a station located at 13° north of the magnetic equator, during both geomagnetic quiet and disturbed conditions in September–October 2011. High‐time‐resolution ionograms from Digisonde Portable Sounder (DPS‐4D) provided the satellite trace measurements that were used to indicate the occurrence of the LSWS. The development of local ESF activity was identified using GPS scintillation and VHF coherent radar echo measurements from the same site, together with the range type spread‐F (RSF) in ionograms. Additionally, the Sanya VHF radar five‐beam scanning measurements in east–west direction were used to characterize the longitudinal difference in establishing the initial conditions for ESF development. Correlative studies between the LSWS and ESF activities during the observational period offer consolidated evidence that the LSWS is a necessary precursor for the ESF development. It is shown that the LSWS and ESF have nearly a one‐to‐one relationship when the F layer undergoes an abrupt post‐sunset rise (PSSR), revealing that the magnitude of the pre‐reversal enhancement in zonal electric field (PRE) that elevates the F layer to a high enough altitude is an important parameter controlling the generation of post‐sunset ESF. However, in the absence of the PSSR, the ESF and GPS scintillation did not always occur following the appearance of LSWS. Sometimes the LSWS events preceded the generation of bottom type spread‐F (BSF) that did not develop vertically into ESF and radar plumes. This result may indicate that under inexpressive, weak, or even moderate PRE conditions, the appearance of the LSWS alone may not be sufficient to produce the post‐sunset F region irregularities responsible for ionospheric scintillations. More factors, other than the LSWS, could play crucial roles favoring the growth of ESF instabilities responsible for ionospheric scintillations.
Solar thematic maps for space weather operations
Authors: Rigler E. Joshua , Hill Steven M. , Reinard Alysha A. , Steenburgh Robert A.
Published: July 2012

Thematic maps are arrays of labels, or “themes,” associated with discrete locations in space and time. Borrowing heavily from the terrestrial remote sensing discipline, a numerical technique based on Bayes' theorem captures operational expertise in the form of trained theme statistics, then uses this to automatically assign labels to solar image pixels. Ultimately, regular thematic maps of the solar corona will be generated from high‐cadence, high‐resolution SUVI images, the solar ultraviolet imager slated to fly on NOAA's next‐generation GOES‐R series of satellites starting ∼2016. These thematic maps will not only provide quicker, more consistent synoptic views of the sun for space weather forecasters, but digital thematic pixel masks (e.g., coronal hole, active region, flare, etc.), necessary for a new generation of operational solar data products, will be generated. This paper presents the mathematical underpinnings of our thematic mapper, as well as some practical algorithmic considerations. Then, using images from the Solar Dynamics Observatory (SDO) Advanced Imaging Array (AIA) as test data, it presents results from validation experiments designed to ascertain the robustness of the technique with respect to differing expert opinions and changing solar conditions.
Dps biomineralizing proteins: multifunctional architects of nature
Authors: Zeth Kornelius
Published: July 2012

Dps proteins are the structural relatives of bacterioferritins and ferritins ubiquitously present in the bacterial and archaeal kingdoms. The ball-shaped enzymes play important roles in the detoxification of ROS (reactive oxygen species), in iron scavenging to prevent Fenton reactions and in the mechanical protection of DNA. Detoxification of ROS and iron chaperoning represent the most archetypical functions of dodecameric Dps enzymes. Recent crystallographic studies of these dodecameric complexes have unravelled species-dependent mechanisms of iron uptake into the hollow spheres. Subsequent functions in iron oxidation at ferroxidase centres are highly conserved among bacteria. Final nucleation of iron as iron oxide nanoparticles has been demonstrated to originate at acidic residues located on the inner surface. Some Dps enzymes are also implicated in newly observed catalytic functions related to the formation of molecules playing roles in bacterium–host cell communication. Most recently, Dps complexes are attracting attention in semiconductor science as biomimetic tools for the technical production of the smallest metal-based quantum nanodots used in nanotechnological approaches, such as memory storage or solar cell development.
Wie bitte geht's nach oben? – Karriereverläufe von Ärztinnen
Authors: van den Bussche Hendrik
Published: July 2012

Der Weg an die Spitze ist ein steiler – besonders für Ärztinnen. Oftmals streben Frauen in der Medizin eine Chefarztposition gar nicht erst an. Besonders Ärztinnen mit Kind haben es schwerer als ihre männlichen Kollegen mit Nachwuchs. Woran das liegt und wie diese Situation verbessert werden kann, untersucht das Projekt „Karriereverläufe von Ärztinnen und Ärzten in der fachärztlichen Weiterbildung“ (KarMed).
Gefällt mir! – Ärztin sein im Zeitalter von Social Media
Authors: Pancur Sarah
Published: July 2012

Immer mehr Patienten greifen auf das Internet zurück, wenn sie Gesundheitsinformationen suchen. Das können sich Ärztinnen und Ärzte zu Nutze machen und mit einer eigenen Web- und Facebook-Seite für ihre Praxis werben.
Mind-Body-Medizin: Die Disziplin gegen den Stress – Biologische und therapeutische Aspekte von Stress, Belohnung und Gesundheit
Authors: Esch Tobias
Published: July 2012

Schon Aristoteles definierte Glück als das oberste Gut, nach dem jeder strebt. Der größte Feind des Glücks ist jedoch der Stress – ihm zu entkommen, ist kein einfacher Prozess. Es gilt, individuelle körperliche und mentale Fähigkeiten eigenverantwortlich einzusetzen, um ein Gleichgewicht zwischen Geist und Körper herzustellen und damit Stress vorzubeugen.
Origin of multiple memory states in organic ferroelectric field-effect transistors
Authors: Kam Benjamin , Li Xiaoran , Cristoferi Claudio , Smits Edsger C. P. , Mityashin Alexander , Schols Sarah , Genoe Jan , Gelinck Gerwin , Heremans Paul
Published: July 2012

In this work, we investigate the ferroelectric polarization state in metal-ferroelectric-semiconductor-metal structures and in ferroelectric field-effect transistors (FeFET). Poly(vinylidene fluoride-trifluoroethylene) and pentacene was used as the ferroelectric and semiconductor, respectively. This material combination in a bottom gate—top contact transistor architecture exhibits three reprogrammable memory states by applying appropriate gate voltages. Scanning Kelvin probe microscopy in conjunction with standard electrical characterization techniques reveals the state of the ferroelectric polarization in the three memory states as well as the device operation of the FeFET.