bluuebunny/crossref_metadata_2025 huggingface dataset:
Quasi‐analytical treatment of spatially averaged radiation transfer in complex terrain
Authors: Löwe H. , Helbig N.
Published: August 2012

We provide a new quasi‐analytical method to compute the subgrid topographic influences on the shortwave radiation fluxes and the effective albedo in complex terrain as required for large‐scale meteorological, land surface, or climate models. We investigate radiative transfer in complex terrain via the radiosity equation on isotropic Gaussian random fields. Under controlled approximations we derive expressions for domain‐averaged fluxes of direct, diffuse, and terrain radiation and the sky view factor. Domain‐averaged quantities can be related to a type of level‐crossing probability of the random field, which is approximated by long‐standing results developed for acoustic scattering at ocean boundaries. This allows us to express all nonlocal horizon effects in terms of a local terrain parameter, namely, the mean‐square slope. Emerging integrals are computed numerically, and fit formulas are given for practical purposes. As an implication of our approach, we provide an expression for the effective albedo of complex terrain in terms of the Sun elevation angle, mean‐square slope, the area‐averaged surface albedo, and the ratio of atmospheric direct beam to diffuse radiation. For demonstration we compute the decrease of the effective albedo relative to the area‐averaged albedo in Switzerland for idealized snow‐covered and clear‐sky conditions at noon in winter. We find an average decrease of 5.8% and spatial patterns which originate from characteristics of the underlying relief. Limitations and possible generalizations of the method are discussed.
A new method for the measurement of meteorite bulk volume via ideal gas pycnometry
Authors: Li Shijie , Wang Shijie , Li Xiongyao , Li Yang , Liu Shen , Coulson Ian M.
Published: August 2012

To date, of the many techniques used to measure the bulk volume of meteorites, only three methods (Archimedean bead method, 3‐D laser imaging and X‐ray microtomography) can be considered as nondestructive or noncontaminating. The bead method can show large, random errors for sample sizes of smaller than 5 cm3. In contrast, 3‐D laser imaging is a high‐accuracy method even when measuring the bulk volumes of small meteorites. This method is both costly and time consuming, however, and meteorites of a certain shape may lead to some uncertainties in the analysis. The method of X‐ray microtomography suffers from the same problems as 3‐D laser imaging. This study outlines a new method of high‐accuracy, nondestructive and noncontaminating measurement of the bulk volume of meteorite samples. In order to measure the bulk volume of a meteorite, one must measure the total volume of the balloon vacuum packaged meteorite and the volume of balloon that had been used to enclose the meteorite using ideal gas pycnometry. The difference between the two determined volumes is the bulk volume of the meteorite. Through the measurement of zero porosity metal spheres and tempered glass fragments, our results indicate that for a sample which has a volume of between 0.5 and 2 cm3, the relative error of the measurement is less than ±0.6%. Furthermore, this error will be even smaller (less than ±0.1%) if the determined sample size is larger than 2 cm3. The precision of this method shows some volume dependence. For samples smaller than 1 cm3, the standard deviations are less than ±0.328%, and these values will fall to less than ±0.052% for samples larger than 2 cm3. The porosities of nine fragments of Jilin, GaoGuenie, Zaoyang and Zhaodong meteorites have been measured using our vacuum packaging–pycnometry method, with determined average porosities of Jilin, GaoGuenie, Zaoyang and Zhaodong of 9.0307%, 2.9277%, 17.5437% and 5.9748%, respectively. These values agree well with the porosities of fragments of which have been measured using the Archimedean bead method and 3‐D laser imaging. This method also may be applied to the study of rare samples in other fields (e.g., archeology and geology).
NMR shielding tensors for density fitted local second-order Møller-Plesset perturbation theory using gauge including atomic orbitals
Authors: Loibl Stefan , Schütz Martin
Published: August 2012

An efficient method for the calculation of nuclear magnetic resonance (NMR) shielding tensors is presented, which treats electron correlation at the level of second-order Møller-Plesset perturbation theory. It uses spatially localized functions to span occupied and virtual molecular orbital spaces, respectively, which are expanded in a basis of gauge including atomic orbitals (GIAOs or London atomic orbitals). Doubly excited determinants are restricted to local subsets of the virtual space and pair energies with an interorbital distance beyond a certain threshold are omitted. Furthermore, density fitting is employed to factorize the electron repulsion integrals. Ordinary Gaussians are employed as fitting functions. It is shown that the errors in the resulting NMR shielding constant, introduced (i) by the local approximation and (ii) by density fitting, are very small or even negligible. The capabilities of the new program are demonstrated by calculations on some extended molecular systems, such as the cyclobutane pyrimidine dimer photolesion with adjacent nucleobases in the native intrahelical DNA double strand (ATTA sequence). Systems of that size were not accessible to correlated ab initio calculations of NMR spectra before. The presented method thus opens the door to new and interesting applications in this area.
Structural and optoelectronic properties, and infrared spectrum of cubic BaSnO3 from first principles calculations
Authors: Moreira E. , Henriques J. M. , Azevedo D. L. , Caetano E. W. S. , Freire V. N. , Fulco U. L. , Albuquerque E. L.
Published: August 2012

The electronic band structure, density of states, dielectric function, optical absorption, and infrared spectrum of cubic BaSnO3 were simulated using density functional theory, within both the local density and generalized gradient approximations, LDA and GGA, respectively. Dielectric optical permittivities and polarizabilities at ω=0 and ω=∞ were also estimated. Indirect band gaps E(R→Γ) of 1.01 eV (LDA) and 0.74 eV (GGA) were found, which are smaller than the experimental one (≈3.1 eV). A comparison of the calculated cubic BaSnO3 band gap with those of others stannates ASnO3 (A = Ca, Sr, Cd) already published highlights their dependence on each crystal profile. The cubic BaSnO3 effective masses of electrons and holes were computed by parabolic fittings along different directions at the conduction band minimum and valence band maximum, being anisotropic for both electrons and holes. The experimental band gap and calculated effective masses confirm the semiconductor character of cubic BaSnO3. Finally, the vibrational normal modes and the infrared spectrum of cubic BaSnO3 were obtained and assigned.
Development and use of a two-dimensional interferometer to measure mass flow from a multi-shell Z-pinch gas puff
Authors: Coleman P. L. , Lamppa D. C. , Madden R. E. , Wilson-Elliott K. , Jones B. , Ampleford D. J. , Bliss D. E. , Jennings C. , Bixler A. , Krishnan M.
Published: August 2012

For gas puff Z-pinches, the K-shell x-ray yield is maximized with the use of a multi-shell nozzle. Optimization of the yield, verification of hydrodynamic models of the nozzle flows, and plausible MHD code modeling of the implosions require data on the radial and axial (R,Z) distribution of mass in the nozzle's flow field. Interferometry is a well-established technique for acquiring such data. We describe the development and use of a two-dimensional interferometer with emphasis on the required data reduction methods. We also show that the instrument can derive the flow from each individual nozzle in a multi-shell system.
High sensitivity microchannel plate detectors for space extreme ultraviolet missions
Authors: Yoshioka K. , Homma T. , Murakami G. , Yoshikawa I.
Published: August 2012

Microchannel plate (MCP) detectors have been widely used as two-dimensional photon counting devices on numerous space EUV (extreme ultraviolet) missions. Although there are other choices for EUV photon detectors, the characteristic features of MCP detectors such as their light weight, low dark current, and high spatial resolution make them more desirable for space applications than any other detector. In addition, it is known that the photocathode can be tailored to increase the quantum detection efficiency (QDE) especially for longer UV wavelengths (100–150 nm). There are many types of photocathode materials available, typically alkali halides. In this study, we report on the EUV (50–150 nm) QDE evaluations for MCPs that were coated with Au, MgF2, CsI, and KBr. We confirmed that CsI and KBr show 2–100 times higher QDEs than the bare photocathode MCPs, while Au and MgF2 show reduced QDEs. In addition, the optimal geometrical parameters for the CsI deposition were also studied experimentally. The best CsI thickness was found to be 150 nm, and it should be deposited on the inner wall of the channels only where the EUV photons initially impinge. We will also discuss the techniques and procedures for reducing the degradation of the photocathode while it is being prepared on the ground before being deployed in space, as adopted by JAXA's EXCEED mission which will be launched in 2013.
Core-flood experiment for transport of reactive fluids in rocks
Authors: Ott H. , de Kloe K. , van Bakel M. , Vos F. , van Pelt A. , Legerstee P. , Bauer A. , Eide K. , van der Linden A. , Berg S. , Makurat A.
Published: August 2012

Investigation of the transport of reactive fluids in porous rocks is an intriguing but challenging task and relevant in several areas of science and engineering such as geology, hydrogeology, and petroleum engineering. We designed and constructed an experimental setup to investigate physical and chemical processes caused by the flow of reactive and volatile fluids such as supercritical CO2 and/or H2S in geological formations. Potential applications are geological sequestration of CO2 in the frame of carbon capture and storage and acid-gas injection for sulfur disposal and/or enhanced oil recovery. The present paper outlines the design criteria and the realization of reactive transport experiments on the laboratory scale. We focus on the spatial and time evolution of rock and fluid composition as a result of chemical rock fluid interaction and the coupling of chemistry and fluid flow in porous rocks.
Pacemaker interactions induce reentrant wave dynamics in engineered cardiac culture
Authors: Borek Bartłomiej , Shajahan T. K. , Gabriels James , Hodge Alex , Glass Leon , Shrier Alvin
Published: August 2012

Pacemaker interactions can lead to complex wave dynamics seen in certain types of cardiac arrhythmias. We use experimental and mathematical models of pacemakers in heterogeneous excitable media to investigate how pacemaker interactions can be a mechanism for wave break and reentrant wave dynamics. Embryonic chick ventricular cells are cultured invitro so as to create a dominant central pacemaker site that entrains other pacemakers in the medium. Exposure of those cultures to a potassium channel blocker, E-4031, leads to emergence of peripheral pacemakers that compete with each other and with the central pacemaker. Waves emitted by faster pacemakers break up over the slower pacemaker to form reentrant waves. Similar dynamics are observed in a modified FitzHugh-Nagumo model of heterogeneous excitable media with two distinct sites of pacemaking. These findings elucidate a mechanism of pacemaker-induced reentry in excitable media.
Spontaneous emission and optical gain characteristics of blue InGaAlN/InGaN quantum well structures with reduced internal field
Authors: Park Seoung-Hwan , Ahn Doyeol
Published: August 2012

Spontaneous emission and optical gain characteristics of blue InGaAlN/InGaN quantum well (QW) structures with reduced internal field were investigated by using the non-Markovian model with many-body effects. The spontaneous emission coefficient of the InGaAlN/InGaN system with reduced internal field is shown to be increased by 30% compared to that of the conventional InGaN/GaN system. This is mainly due to the increase in the optical matrix element by the reduced internal field effect. If the threshold optical gain is assumed to be about 13000cm−1, the InGaAlN/InGaN QW structure is expected to have smaller threshold current density the InGaN/GaN QW structure. In the case of the InGaAlN/InGaN system, the transition wavelength is a weak function of the carrier density.
Formation of thermally induced ground states in two-dimensional square spin ices
Authors: John Greaves Simon , Muraoka Hiroaki
Published: August 2012

The growth of a two dimensional square ice formed from arrays of nanoscale magnetic islands was simulated. Ordering of the magnetic moments was investigated as a function of growth rate, island aspect ratio, and island pitch. Arrays of islands with low switching fields and slow growth rates showed the highest degree of ordering in the as-deposited state. Subsequently, simulations of annealing were carried out in which islands were heated to the Curie temperature and cooled at various rates. Slower cooling rates left the island arrays in states with higher order. The level of ordering that could be achieved in an array of islands was found to be closely linked to the ratio of the average magnetostatic field acting on an island to its anisotropy field.
Magnetic and electrical transport properties of Pb1-xLaxTi1-xMnxO3 ceramics
Authors: Xu Jie , Wang Jin-Feng , Jiao Long , Ji Weijing , Zhou Jian , Gu Zheng-Bin , Chen Y. B. , Yao Shu-Hua , Zhang Shan-Tao , Chen Yan-Feng
Published: August 2012

Pb1-xLaxTi1-xMnxO3 (PLTM100x, x = 0.20, 0.40, 0.50, 0.60, and 0.80) ceramics have been prepared and investigated. X-ray diffractions show all ceramics are crystallized into perovskite structures with tetragonal symmetry for PLTMO20 and orthorhombic symmetry for the other compositions. X-ray photoelectron spectroscopy results confirm that the Mn cations in PLTMO20 and PLTMO40 have the valence state of +3, whereas in other compositions, the Mn cations have mixed valences states of +3 and +4. With increasing x from 0.20 to 0.80, the materials change from superparamagnetic to coexisting ferromagnetic and antiferromagnetic magnetic behaviour whereas all compositions persist insulating behaviour, as confirmed by the magnetization-magnetic field (M-H), the temperature dependent magnetization (M-T) and transport measurements. Especially, the PLTMO80 has a large negative magnetoresistance of −41.5% at 10 K with the applied filed of 2 T. By considering the chemical states of Mn cations, these results are attributed to that the coexistence of metallic ferromagnetic and insulating non-ferromagnetic phases.
Characteristics of an educational publication sourced from deaths investigated by the Coroner that is reported to have promoted practice change
Authors: McInnes Judith A. , Ibrahim Joseph E.
Published: August 2012

Objective. The purpose of this study was to investigate the characteristics of the Residential Aged Care Coronial Communiqué that have promoted previously reported professional practice change, and to explore the circumstances of these changes. Methods. This was an exploratory, qualitative study for which data was collected through semi-structured interview of 15 subscribers to the Residential Aged Care Coronial Communiqué. Results. The Residential Aged Care Coronial Communiqué was reported to promote self-reported practice change though the inclusion of case studies, by being associated with the Coroner, and by providing evidence to justify change. The combination of existing concerns about risk and staff awareness, in conjunction with reading the Residential Aged Care Coronial Communiqué was also reported to promote practice change, as was having the support of senior staff and the authority to implement change. Conclusions. The combination of narrative case studies in the context of an educational publication associated with the Coroner’s Office has been reported to provided evidence and incentive to promote professional practice change in an aged care setting. However the relative influence of the Residential Aged Care Coronial Communiqué, and other background circumstance and facilitating factors on practice change cannot be determined from this study. What is known about the topic? Passive dissemination of written educational material has little or no impact on altering clinical practice. What does this paper add? Exploratory research findings published in this paper provide insight into characteristics of an electronic, educational publication for a health professional audience reported to have promoted practice change in a residential aged care setting. What are the implications for practitioners? The inclusion of short, clearly written case studies that describe real situations that have been investigated by the Coroner, in the context of a publication associated with the Coroner’s Office, has been reported to motivate staff to change professional practice to improve safety in a residential aged care setting.
An assessment of the taxonomic status of wild canids in south-eastern New South Wales: phenotypic variation in dingoes
Authors: Radford Cameron G. , Letnic Mike , Fillios Melanie , Crowther Mathew S.
Published: August 2012

In Australia, the genetic integrity of dingoes (Canis lupus dingo) is threatened through hybridisation with feral dogs and consequently the identification of the modern ‘pure’ dingo is ambiguous. There are no accurate classification techniques for dingoes and dingo–dog hybrids in the wild. Genetics, skull morphology and visual assessment are methods currently used, but they often yield contrasting results. We tested skull morphological and visual assessment methods for classifying wild canids in south-eastern New South Wales and examined temporal and geographic trends in skull morphology. Published equations based on discriminant functions revealed varying percentages of dingoes, dogs and their hybrids over time, and did not yield similar results to visual assessment methods. Skull characteristics generally became larger over time but have recently stabilised. Changes in the morphology of the molars were consistent with the occurrence of hybridisation with dogs. Geographic variation was apparent and consistent with Bergmann’s Law, with skulls increasing in size with altitude. This study highlights the importance for improved classification methods of wild canids and the importance of considering geographical variation in morphological studies.
Cancer radiotherapy based on femtosecond IR laser-beam filamentation yielding ultra-high dose rates and zero entrance dose
Authors: Meesat Ridthee , Belmouaddine Hakim , Allard Jean-François , Tanguay-Renaud Catherine , Lemay Rosalie , Brastaviceanu Tiberius , Tremblay Luc , Paquette Benoit , Wagner J. Richard , Jay-Gerin Jean-Paul , Lepage Martin , Huels Michael A. , Houde Daniel
Published: August 2012

Since the invention of cancer radiotherapy, its primary goal has been to maximize lethal radiation doses to the tumor volume while keeping the dose to surrounding healthy tissues at zero. Sadly, conventional radiation sources (γ or X rays, electrons) used for decades, including multiple or modulated beams, inevitably deposit the majority of their dose in front or behind the tumor, thus damaging healthy tissue and causing secondary cancers years after treatment. Even the most recent pioneering advances in costly proton or carbon ion therapies can not completely avoid dose buildup in front of the tumor volume. Here we show that this ultimate goal of radiotherapy is yet within our reach: Using intense ultra-short infrared laser pulses we can now deposit a very large energy dose at unprecedented microscopic dose rates (up to 10
11
 Gy/s) deep inside an adjustable, well-controlled macroscopic volume, without any dose deposit in front or behind the target volume. Our infrared laser pulses produce high density avalanches of low energy electrons via laser filamentation, a phenomenon that results in a spatial energy density and temporal dose rate that both exceed by orders of magnitude any values previously reported even for the most intense clinical radiotherapy systems. Moreover, we show that (
i
) the type of final damage and its mechanisms in aqueous media, at the molecular and biomolecular level, is comparable to that of conventional ionizing radiation, and (
ii
) at the tumor tissue level in an animal cancer model, the laser irradiation method shows clear therapeutic benefits.
The jeunes de langues in the eighteenth century
Authors: Cáceres-Würsig Ingrid
Published: August 2012

This article explores the history in Europe of the training of interpreters specialized in diplomacy, which began in the Renaissance Venetian Republic, when this European power started to train the so-called giovani di lingua in its embassy in Constantinople. The Venetian model was imitated and developed by other European powers, especially by France and the Austrian monarchy, trying to strengthen their relations with the Ottoman Empire by training their own jeunes de langues and Sprachknaben, respectively. In Spain the equivalent figure, the joven de lenguas, emerged later, in the last third of the 18th century, and there is evidence of several proposals to create a Spanish school to train these youngsters. The profile of the selected jóvenes who would serve at the Spanish embassies and consulates in foreign regions is also analyzed. Finally, the Spanish example is compared with the pioneering European models, especially with the Venetian, the French and the Austrian ones.
Complexities of high profile interpreting
Authors: Martin Anne , Taibi Mustapha
Published: August 2012

This paper examines the experience, perceptions and narratives of the interpreters who worked at the trial of the Madrid terrorist attacks of 11th March 2004. Using semi-structured interviews as an instrument, information was sought from the members of the interpreting team regarding their role and self-image, their relationship with other professionals during the trial, their management of emotions, pressure and possible conflict, as well as the effect of a high profile case such as this on their interpreting performance. The findings show that the interpreters were generally clear and confident about their professional role and capacity, that their working conditions were inadequate, especially at the beginning of the trial, and that the experience heightened the awareness of other court professionals with regard to interpreting. The nature of the trial, the presence of national and international media, as well as the immense responsibility the interpreters assumed in this case created an atmosphere of intense emotion and pressure. However, most of the participants in this study reported that this did not affect their professional performance.
The significance of interpreting modes for question–answer dialogues in court interpreting
Authors: Jacobsen Bente
Published: August 2012

Studies of court interpreting have so far neglected interpreters’ choice of mode for interpreting question–answer dialogues, though their choice of mode may impact the way questions and answers are reproduced and received by end receivers. Typically, the (short) consecutive mode, regarded as the more complete mode, is recommended for interpreting these dialogues, because it facilitates the inclusion of features such as hesitations, discourse markers, repetitions etc. which play a significant role in identifying speaker meaning. Moreover, in courts without interpreting equipment, answers interpreted in the simultaneous (whispered) mode will be inaudible to end receivers. Nevertheless, as demonstrated in this article, which is based on a survey among court interpreters in Denmark, some interpreters ignore official recommendations and choose strategies for interpreting questions and answers which potentially hinder the flow of information between the original speaker and listener and the accurate and complete translation of original utterances. Furthermore, Danish courts seem to accept the court interpreters’ behaviour, despite its potential consequences for trial outcomes. The article discusses the reasons for this passivity and its wider implications.
The Effects of Neutrally Buoyant, Externally Attached Transmitters on Swimming Performance and Predator Avoidance of Juvenile Chinook Salmon
Authors: Janak Jill M. , Brown Richard S. , Colotelo Alison H. , Pflugrath Brett D. , Stephenson John R. , Deng Z. Daniel , Carlson Thomas J. , Seaburg Adam G.
Published: August 2012

Migrating juvenile salmonids experience rapid decompression that could result in injury or mortality due to barotrauma as they pass turbines at hydropower facilities. Recent research indicates that the risk of injury or mortality due to barotrauma is higher in fish bearing surgically implanted transmitters. Since tagged fish are used to represent the entire population, this tag effect potentially leads to inaccuracies in survival estimates for fish passing turbines. This problem led to development of a novel transmitter, the use of which may eliminate bias associated with the passage of transmitter‐bearing fish through turbines. Juvenile Chinook salmon Oncorhynchus tshawytscha were tagged with two different neutrally buoyant, externally attached transmitters (types A and B). The effects of transmitter presence on swimming performance were examined by comparing critical swimming speeds (Ucrit; an index of prolonged swimming performance) of externally tagged fish, untagged individuals, and fish that received surgically implanted Juvenile Salmon Acoustic Telemetry System acoustic transmitters. Fish tagged with external transmitters had lower Ucrit than untagged individuals. However, there was no difference in Ucrit between fish with external transmitter type A or B and fish with surgically implanted transmitters. Testing was conducted to determine whether predator avoidance was affected by the presence of type A transmitters compared with untagged fish. No difference in predation mortality was detected between tagged and untagged fish. Although results suggest that Ucrit was affected by externally attached transmitters in comparison with untagged fish, the overall impact as reflected by survival was similar; field‐based survival studies involving juvenile salmonids passing through hydroturbines are recommended. The absence of swimming performance effects in fish with external tags relative to fish with internally implanted transmitters and the lack of an increased predation risk relative to untagged fish suggest that an externally attached, neutrally buoyant transmitter is a viable option for telemetry studies in estimating survival of juvenile salmonids passing through hydroturbines.
Tuning of EAG K+ channel inactivation: Molecular determinants of amplification by mutations and a small molecule
Authors: Garg Vivek , Sachse Frank B. , Sanguinetti Michael C.
Published: August 2012

Ether-à-go-go (EAG) and EAG-related gene (ERG) K+ channels are close homologues but differ markedly in their gating properties. ERG1 channels are characterized by rapid and extensive C-type inactivation, whereas mammalian EAG1 channels were previously considered noninactivating. Here, we show that human EAG1 channels exhibit an intrinsic voltage-dependent slow inactivation that is markedly enhanced in rate and extent by 1–10 µM 3-nitro-N-(4-phenoxyphenyl) benzamide, or ICA105574 (ICA). This compound was previously reported to have the opposite effect on ERG1 channels, causing an increase in current magnitude by inhibition of C-type inactivation. The voltage dependence of 2 µM ICA-induced inhibition of EAG1 current was half-maximal at −73 mV, 62 mV negative to the half-point for channel activation. This finding suggests that current inhibition by the drug is mediated by enhanced inactivation and not open-channel block, where the voltage half-points for current inhibition and channel activation are predicted to overlap, as we demonstrate for clofilium and astemizole. The mutation Y464A in the S6 segment also induced inactivation of EAG1, with a time course and voltage dependence similar to that caused by 2 µM ICA. Several Markov models were investigated to describe gating effects induced by multiple concentrations of the drug and the Y464A mutation. Models with the smallest fit error required both closed- and open-state inactivation. Unlike typical C-type inactivation, the rate of Y464A- and ICA-induced inactivation was not decreased by external tetraethylammonium or elevated [K+]e. EAG1 channel inactivation introduced by Y464A was prevented by additional mutation of a nearby residue located in the S5 segment (F359A) or pore helix (L434A), suggesting a tripartite molecular model where interactions between single residues in S5, S6, and the pore helix modulate inactivation of EAG1 channels.
On the standard canonical form of time-varying linear DAEs
Authors: Berger Thomas , Ilchmann Achim
Published: August 2012

We introduce a solution theory for time-varying linear differential-algebraic equations (DAEs)

E
(
t
)

x
˙

=
A
(
t
)
x

E(t)\dot x=A(t)x

which can be transformed into standard canonical form (SCF); i.e., the DAE is decoupled into an ODE

z
˙

1

=
J
(
t
)

z
1

\dot z_1 = J(t)z_1

and a pure DAE

N
(
t
)

z
˙

2

=

z
2

N(t) \dot z_2 = z_2

, where 

N
N

is pointwise strictly lower triangular. This class is a time-varying generalization of time-invariant DAEs where the corresponding matrix pencil is regular. It will be shown in which sense the SCF is a canonical form, that it allows for a transition matrix similar to the one for ODEs, and how this can be exploited to derive a variation of constants formula. Furthermore, we show in which sense the class of systems transferable into SCF is equivalent to DAEs which are analytically solvable, and relate SCF to the derivative array approach, differentiation index and strangeness index. Finally, an algorithm is presented which determines the transformation matrices which put a DAE into SCF.
Decay of mass for fractional evolution equation with memory term
Authors: Fino Ahmad , Ibrahim Hassan , Barakeh Bilal
Published: August 2012

We investigate the decay properties of the mass

M
(
t
)
=

∫

R

N

u
(
⋅
,
t
)
d
x

M(t)= \int _{\mathbb {R}^N} u(\cdot ,t)dx

of the solutions of a fractional diffusion equation with nonlinear memory term. We show, using a suitable class of initial data and a restriction on the diffusion and nonlinear term, that the memory term determines the large time asymptotics; that is,

M
(
t
)

M(t)

tends to zero as

t
→
∞
.

t\to \infty .
The brain's connective core and its role in animal cognition
Authors: Shanahan Murray
Published: August 2012

This paper addresses the question of how the brain of an animal achieves cognitive integration—that is to say how it manages to bring its fullest resources to bear on an ongoing situation. To fully exploit its cognitive resources, whether inherited or acquired through experience, it must be possible for unanticipated coalitions of brain processes to form. This facilitates the novel recombination of the elements of an existing behavioural repertoire, and thereby enables innovation. But in a system comprising massively many anatomically distributed assemblies of neurons, it is far from clear how such open-ended coalition formation is possible. The present paper draws on contemporary findings in brain connectivity and neurodynamics, as well as the literature of artificial intelligence, to outline a possible answer in terms of the brain's most richly connected and topologically central structures, its so-called connective core.
Linking behavioural syndromes and cognition: a behavioural ecology perspective
Authors: Sih Andrew , Del Giudice Marco
Published: August 2012

With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast–slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed–accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.
Chimpanzee ‘folk physics’: bringing failures into focus
Authors: Seed Amanda , Seddon Eleanor , Greene Bláthnaid , Call Josep
Published: August 2012

Differences between individuals are the raw material from which theories of the evolution and ontogeny of cognition are built. For example, when 4-year-old children pass a test requiring them to communicate the content of another's falsely held belief, while 3-year-olds fail, we know that something must change over the course of the third year of life. In the search for what develops or evolves, the typical route is to probe the extents and limits of successful individuals' ability. Another is to focus on those that failed, and find out what difference or lack prevented them from passing the task. Recent research in developmental psychology has harnessed individual differences to illuminate the cognitive mechanisms that emerge to enable success. We apply this approach to explaining some of the failures made by chimpanzees when using tools to solve problems. Twelve of 16 chimpanzees failed to discriminate between a complete and a broken tool when, after being set down, the ends of the broken one were aligned in front of them. There was a correlation between performance on this
aligned
task and another in which after being set down, the centre of both tools was
covered
, suggesting that the limiting factor was not the representation of connection, but memory or attention. Some chimpanzees that passed the aligned task passed a task in which the location of the broken tool was never visible but had to be inferred.
PSA: software for parental structure analysis of seed or seedling patches
Authors: Robledo‐Arnuncio J. J. , Grivet D. , Smouse P. E. , Sork V. L.
Published: August 2012

Parental structure analysis (PSA) is a computer program to analyse separate contributions of paternal and maternal parents to postdispersal plant offspring. The program provides joint estimates of maternal, paternal and cross‐parental correlations within and among a set of predefined groups of seeds or seedlings, as well as derivative estimates of effective parental numbers. PSA utilizes data sets that distinguish between maternal and paternal contributions to the genotype of each offspring in the sample, but does not require parental samples per se. The approach requires assay of codominant diploid markers from both seed coat (maternally inherited) and seedling/embryo (biparentally inherited) tissues for each offspring. A simulation analysis of PSA's performance shows that it provides fairly accurate parental correlation estimates from affordable sampling effort. PSA should be of interest to plant biologists studying the interplay between dispersal, demography and genetics, as well as plant–animal interactions.
Complement in Pregnancy: A Delicate Balance
Authors: Denny Kerina J. , Woodruff Trent M. , Taylor Stephen M. , Callaway Leonie K.
Published: August 2012

The complement system is a key component of innate host defence that, under normal conditions, is responsible for the opsonization and destruction of potential pathogens. However, inappropriate or excessive activation of complement can have a detrimental effect on the host and has been implicated in the pathophysiology of numerous disease states. Recently, there has been increasing evidence for a role of the complement system and, in particular, the potent pro‐inflammatory anaphylatoxin complement component 5a (C5a) in both normal and complicated pregnancy. The following review describes the results of in vitro, animal, and human clinical studies investigating the role of the complement system in healthy pregnancy, recurrent miscarriage, preterm birth, and preeclampsia.
The clinical picture of juvenile parotitis in a prospective setup
Authors: Saarinen Riitta , Kolho Kaija‐Leena , Davidkin Irja , Pitkäranta Anne
Published: August 2012

Aim:  To characterize the features of juvenile parotitis in a prospective setup and epidemiology.

Methods:  All children with parotitis admitted to Helsinki University Central Hospital 2005–2010 were recruited. Clinical characteristics, given treatment, outcome, blood leukocyte count, C‐reactive protein, serum amylase and trypsinogen, SPINK‐1 genotype and mumps antibodies were recorded. To map the epidemiology, a questionnaire was sent to 1000 randomly selected 13‐year‐old children.

Results:  The prospective study included 41 children (aged ≤ 17) with acute parotitis, all in good general condition. Serum amylase, but not trypsinogen, was elevated in majority of the cases (79%) and C‐reactive protein in 68%. Eleven (27%) children had an elevated blood leukocyte count. None had acute mumps. Most children recovered well, 51% being treated symptomatically only. Seven children were treated on ward. Seventeen (46%) children had recurrent symptoms. One child (2.4%) had SPINK P55S mutation. According to the epidemiological questionnaire, 1.1% of the respondents (8/728, response rate 73%) reported a verified episode(s) of parotitis.

Conclusion:  Juvenile parotitis has a frequency close to 1%. In the majority, the general condition is good during the episode. Serum amylase serves as an additional marker for the disease. Parotitis has a tendency to recur in almost half of the cases.
Timing of allergy‐preventive and immunomodulatory dietary interventions – are prenatal, perinatal or postnatal strategies optimal?
Authors: Jenmalm M. C. , Duchén K.
Published: August 2012

The increasing allergy prevalence in affluent countries may be caused by reduced microbial stimulation and a decreased dietary ω‐3/ω‐6 long‐chain polyunsaturated fatty acid (LCPUFA) ratio, resulting in an abnormal postnatal immune maturation. The timing of allergy‐preventive probiotic and ω‐3 LCPUFA interventions is critical, as early‐life events occurring during critical windows of immune vulnerability can have long‐term impact on immune development. The maternal dietary and microbial environment during pregnancy may programme the immune development of the child. Prenatal environmental exposures may alter gene expression via epigenetic mechanisms, aiming to induce physiological adaptations to the anticipated postnatal environment, but potentially also increasing disease susceptibility in the offspring if exposures are mismatched. Although the importance of fetal programming mostly has been studied in cardiovascular and metabolic disease, this hypothesis is also very attractive in the context of environmentally influenced immune‐mediated diseases. This review focuses on how prenatal, perinatal or postnatal ω‐3 LCPUFA interventions regulate childhood immune and allergy development, and if synergistic effects may be obtained by simultaneous probiotic supplementation. We propose that combined pre‐ and postnatal preventive measures may be most efficacious. Increasing knowledge on the immunomodulatory effects of prenatal, perinatal and postnatal interventions will help to direct future strategies to combat the allergy epidemic.
Dietary restriction and exercise improve airway inflammation and clinical outcomes in overweight and obese asthma: a randomized trial
Authors: Scott H. A. , Gibson P. G. , Garg M. L. , Pretto J. J. , Morgan P. J. , Callister R. , Wood L. G.
Published: August 2012

Background

Obesity and asthma are associated conditions; however, the mechanisms linking the two remain unclear. Few studies have examined the effects of weight loss on inflammation and clinical outcomes in obese–asthma.

Objective

To compare the effects of weight loss achieved by dietary restriction, exercise or combined dietary restriction and exercise on airway inflammation and clinical outcomes in overweight and obese adults with asthma.

Methods

Participants (n = 46; 54.3% female, body mass index (mean ± SD) 33.7 ± 3.5 kg/m2) were randomized to complete a 10‐week dietary, exercise or combined dietary and exercise intervention. Dual‐energy x‐ray absorptiometry was performed, the Juniper Asthma Control Questionnaire and Juniper Asthma Quality of Life Questionnaire completed and inflammatory markers, dietary intake and physical activity measured. The trial was registered with the Australian Clinical Trials Registry: ACTRN12611000235909.

Results

Retention was 82.6%. Mean ± SD weight loss was 8.5 ± 4.2%, 1.8 ± 2.6% and 8.3 ± 4.9% after the dietary, exercise and combined interventions respectively. Asthma control improved after the dietary (mean ± SD; −0.6 ± 0.5, P ≤ 0.001) and combined interventions (−0.5 ± 0.7, P = 0.040), whereas quality of life improved after the dietary [median (IQR); 0.9 (0.4, 1.3), P = 0.002], exercise [0.49 (0.03, 0.78), P = 0.037] and combined [0.5 (0.1, 1.0), P = 0.007] interventions. A 5–10% weight loss resulted in clinically important improvements to asthma control in 58%, and quality of life in 83%, of subjects. Gynoid adipose tissue reduction was associated with reduced neutrophilic airway inflammation in women [β‐coefficient (95% CI); 1.75 (0.02, 3.48), P = 0.047], whereas a reduction in dietary saturated fat was associated with reduced neutrophilic airway inflammation in males (r = 0.775, P = 0.041). The exercise intervention resulted in a significant reduction to sputum eosinophils [median (IQR); −1.3 (−2.0, −1.0)%, P = 0.028].

Conclusion and clinical relevance

This study suggests a weight‐loss goal of 5–10% be recommended to assist in the clinical management of overweight and obese adults with asthma. The obese–asthma phenotype may involve both innate and allergic inflammatory pathways.
Nasal cytokine responses to natural colds in asthmatic children
Authors: Lewis T. C. , Henderson T. A. , Carpenter A. R. , Ramirez I. A. , McHenry C. L. , Goldsmith A. M. , Ren X. , Mentz G. B. , Mukherjee B. , Robins T. G. , Joiner T. A. , Mohammad L. S. , Nguyen E. R. , Burns M. A. , Burke D. T. , Hershenson M. B.
Published: August 2012

Background

The mechanisms by which viruses induce asthma exacerbations are not well understood.

Objective

We characterized fluctuations in nasal aspirate cytokines during naturally occurring respiratory viral infections in children with asthma.

Methods

Sixteen children underwent home collections of nasal aspirates when they were without cold symptoms and again during self‐reported respiratory illnesses. The presence of viral infection was ascertained by multiplex PCR. Cytokines were measured using multiplex immune assay. mRNA expression for selected markers of viral infection was measured using RT‐PCR. A cumulative respiratory symptom score was calculated for each day of measurement. Generalized estimated equations were used to evaluate associations between viral infection and marker elevation, and between marker elevation and symptom score.

Results

The 16 patients completed a total of 37 weeks of assessment (15 ‘well’ weeks; 22 self‐assessed ‘sick’ weeks). Viral infections were detected in 3 of the ‘well’ weeks and 17 of the ‘sick’ weeks (10 rhinovirus, three coronavirus, two influenza A, two influenza B, two respiratory syncytial virus, one parainfluenza). Compared to virus‐negative well weeks, nasal aspirate IFN‐γ, CXCL8/IL‐8, CXCL10/IP‐10, CCL5/RANTES, CCL11/eotaxin‐1, CCL2/MCP‐1, CCL4/MIP‐1β, CCL7/MCP‐3, and CCL20/MIP3α protein levels increased during virus‐positive sick weeks. Only a subset of cytokines (IFN‐γ, CXCL8, CCL2, CCL4, CCL5, and CCL20) correlated with self‐reported respiratory tract symptoms. While many aspirates were dilute and showed no mRNA signal, viral infection significantly increased the number of samples that were positive for IFN‐λ1, IFN‐λ2/3, TLR3, RIG‐I, and IRF7 mRNA.

Conclusions and clinical relevance

We conclude that in children with asthma, naturally occurring viral infections apparently induce a robust innate immune response including expression of specific chemokines, IFNs, and IFN‐responsive genes.
Higher TSH level is a risk factor for differentiated thyroid cancer
Authors: Kim Hee Kyung , Yoon Jee Hee , Kim Soo Jeong , Cho Jin Seong , Kweon Sun‐Seog , Kang Ho‐Cheol
Published: August 2012

Objectives

Higher thyroid‐stimulating hormone (TSH) levels are associated with differentiated thyroid cancers (DTC). To validate this association, we compared TSH levels obtained from euthyroid patients with DTC with TSH levels from controls in the general population.

Design and patients

The case group included 1759 patients with DTC, who underwent thyroid surgery at Chonnam National University Hwasun Hospital. The control group (n = 1548), who had participated in the Thyroid Disease Prevalence Study were used as a healthy control group. The subjects were divided into four groups of similar size according to their TSH levels, with the first quartile used as a reference group.

Results

The mean TSH level of the case group was significantly higher than the mean TSH level of the control group (1.95 ± 0.9 mIU/l vs 1.62 ± 0.8 mIU/l, P < 0.001), and was associated with DTC risk. Multiple logistic regression, after controlling for age, gender and the presence of a family history of thyroid cancer, showed that the odds ratios and 95% confidence intervals for the second, third and fourth quartiles of TSH levels were 1.27 (1.03–1.57), 1.55 (1.25–1.92) and 2.21 (1.78–2.74) respectively. No significant differences were observed in mean TSH levels in patients with different tumour stages and tumour sizes.

Conclusion

Having a high TSH level within the normal range is an independent risk factor for DTC, and may contribute to the initiation of thyroid carcinogenesis. TSH levels in patients with thyroid nodules may be used as diagnostic adjuncts for the identification of high‐risk patients, who require further investigation and/or surgical intervention.
A simple new non‐invasive sweat indicator test for the diagnosis of diabetic neuropathy
Authors: Papanas N. , Boulton A. J. M. , Malik R. A. , Manes C. , Schnell O. , Spallone V. , Tentolouris N. , Tesfaye S. , Valensi P. , Ziegler D. , Kempler P.
Published: August 2012

A simple non‐invasive indicator test (Neuropad®) has been developed for the assessment of sweating and, hence, cholinergic innervation in the diabetic foot. The present review summarizes current knowledge on this diagnostic test. The diagnostic ability of this test is based on a colour change from blue to pink at 10 min, with excellent reproducibility, which lends itself to patient self‐examination. It has a high sensitivity (65.1–100%) and negative predictive value (63–100%), with moderate specificity (32–78.5%) and positive predictive value (23.3–93.2%) for the diagnosis of diabetic peripheral neuropathy. It also has moderate to high sensitivity (59.1–89%) and negative predictive value (64.7–91%), but low to moderate specificity (27–78%) and positive predictive value (24–48.6%) for the diagnosis of diabetic cardiac autonomic neuropathy. There are some data to suggest that Neuropad can detect early diabetic neuropathy, but this needs further evaluation. It remains to be established whether this test can predict foot ulceration and amputation, thereby contributing to the identification of high‐risk patients.

Diabet. Med. 30, 525–534 (2013)