bluuebunny/crossref_metadata_2025 huggingface dataset:
Notions of property: traditional land use and boundaries in the Deh Cho region
Authors: Brown-Leonardi Carol J.
Published: May 2012

The Deh Cho Dene have been negotiating territorial land since early European settlement. This paper argues that the changing needs of Deh Cho Dene society has changed their concept of property and this transformation has evolved with a responsibility to conserve cultural practice and ecological balance in Deh Cho Dene territorial lands. The article considers how the changing need of European society addresses property and ownership in the context of basic human rights and consumer interests. It uses the theories of Macpherson, Locke, and Marx to construct a model to understand the property relations that exist in the Deh Cho Dene region. Accordingly, the paper addresses oral narratives to give historical insight into the relations between neighbouring tribal groups and their understanding of territorial boundaries. An account of present day negotiations highlights the various initiatives taken to protect traditional interests and uphold historical claim to the territory. The negotiation of joint ventures and property ownership has evolved with concerns over ecological sustainability and the protection of a subsistence lifestyle, which is critical for the social and economic interests of Deh Cho Dene culture, and is closely connected to the land.
Introduction: Contested borders and identities
Authors: Brown-Leonardi Carol J. , Fossland Trine , Fryer Paul
Published: May 2012

This publication is one result of the thematic session ‘Contested borders and identities’ organised at the conference entitled Contested identities, contested cultures and contested rights – Change and challenges in the Northern European periphery held on 23–25 September 2009 at the University of Tromsø, Norway. The conference was organised and financed by the university's Citizenship, encounters and place enactment in the north (CEPIN) group, a multi-disciplinary research school that examines globalisation and modernisation processes in the north. The conference gathered researchers from 19 countries representing different fields of social sciences and addressed various issues relating to political, economic, social and cultural processes in the north.
Density of half-horocycles on geometrically infinite hyperbolic surfaces
Authors: SCHAPIRA BARBARA
Published: May 2012

On the unit tangent bundle of a hyperbolic surface, we study the density of positive orbits $(h^s v)_{s\ge 0}$ under the horocyclic flow. More precisely, given a full orbit $(h^sv)_{s\in {\mathbb R}}$, we prove that under a weak assumption on the vector $v$, both half-orbits $(h^sv)_{s\ge 0}$ and $(h^s v)_{s\le 0}$ are simultaneously dense or not in the non-wandering set $\mathcal {E}$of the horocyclic flow. We give also a counterexample to this result when this assumption is not satisfied.
Disaster Mobile Health Technology: Lessons from Haiti
Authors: Callaway David W. , Peabody Christopher R. , Hoffman Ari , Cote Elizabeth , Moulton Seth , Baez Amado Alejandro , Nathanson Larry
Published: May 2012

Introduction

Mobile health (mHealth) technology can play a critical role in improving disaster victim tracking, triage, patient care, facility management, and theater-wide decision-making.

Problem

To date, no disaster mHealth application provides responders with adequate capabilities to function in an austere environment.

Methods

The Operational Medicine Institute (OMI) conducted a qualitative trial of a modified version of the off-the-shelf application iChart at the Fond Parisien Disaster Rescue Camp during the large-scale response to the January 12, 2010 earthquake in Haiti.

Results

The iChart mHealth system created a patient log of 617 unique entries used by on-the-ground medical providers and field hospital administrators to facilitate provider triage, improve provider handoffs, and track vulnerable populations such as unaccompanied minors, pregnant women, traumatic orthopedic injuries and specified infectious diseases.

Conclusion

The trial demonstrated that even a non-disaster specific application with significant programmatic limitations was an improvement over existing patient tracking and facility management systems. A unified electronic medical record and patient tracking system would add significant value to first responder capabilities in the disaster response setting.

Callaway DW, Peabody CR, Hoffman A, Cote E, Moulton S, Baez AA, Nathanson L. Disaster mobile health technology: lessons from Haiti. Prehosp Disaster Med. 2012;27(2):1-5.
Pediatric Road Traffic Accident Deaths Presenting to a Nigerian Referral Center
Authors: Osifo Osarumwense David , Osagie Theophilus Osasumwen , Iribhogbe Pius Ehiawaguan
Published: May 2012

Introduction

Road traffic accident (RTA) is a common cause of pediatric trauma death and disability, constituting a worldwide loss of financial resources and potential manpower. This study was designed to determine the causes, prehospital care, presentation, and injuries that resulted in deaths among pediatric victims of RTA in Nigeria, and to make suggestions, based on the study data, to reduce RTA deaths.

Methods

This is a retrospective analysis of pediatric RTA presenting to a Nigerian referral center. The records of all pediatric RTA between January 2006 and December 2010 at the University of Benin Teaching Hospital were analyzed for age, gender, causes of death, injury, rescue team prehospital treatment, injury to hospital arrival time, clinical condition on arrival, treatment, duration of hospitalization before death, challenges, and postmortem findings.

Results

Twenty-six (18%) of 143 pediatric RTA, comprising 18 males and 8 females, between less than one and 18 (mean 9.3 ± 5.2) years of age died. There was no significant statistical demographic difference observed when 15 (58%) deaths recorded among 67 (46.9%) children involved in motor vehicle accidents were compared with 11 (42%) involved in 76 (53.1%) motorcycle accidents (P= .31). More severe injuries resulting in the majority of deaths were associated with alcohol intoxication (P< .0001). Fourteen (54%) of the deaths were pedestrians, eight of whom were selling wares on the roadside; six were crossing roads that had no traffic signs or traffic control. Of the eight vehicle passengers who died, only two wore seat belts or used pediatric car seats, with no statistical significance compared to those who did not use seat belts or car seats (P= .37). Four of 14 front seat passengers and four of 32 rear seat passengers died (P= .222). Of motorcycle passengers, none of those who wore protective crash helmets died, while four died who were not wearing helmets. Passers-by and sympathizers served as rescuers provided emergency treatment, and presented the victims between one hour and four days after the accidents. Head injury in 14 (54%) cases was the most common cause of death.

Conclusion

Pediatric RTA deaths in this study were due mainly to preventable causes. There is a need to stress road safety education to children, drivers, the general public and government policy formulators, and to adopt RTA preventive measures in this region of Nigeria.

Osifo OD, Osagie TO, Iribhogbe PE. Pediatric road traffic accident deaths presenting to a Nigerian referral center.Prehosp Disaster Med.2012;27(2):1-6.
Millet transactions in market fairs, millet diversity and farmer welfare in Mali
Authors: Smale Melinda , Diakité Lamissa , Keita Naman
Published: May 2012

Although farmers in the Malian Sahel depend on millet for survival, demand and supply constraints have impeded their use of certified seed. We use data collected from households, vendors and seed samples to test the way market purchases of grain and seed affect household food consumption and millet genetic diversity. Purchase of millet grain in markets contributes to food security, but reduces dietary diversity – suggesting that scarce cash was directed toward meeting staple food needs first. Farmers purchased millet grain for seed only in the site with riskier rainfall and smaller market fairs. Although they were more likely to purchase in markets where the genetic dissimilarity of seed was higher, purchasing seed in markets was negatively associated with on-farm diversity. Seed shortage rather than variety experimentation appears to be the motivation for seed purchase. Introducing certified seed in rural markets through small-scale traders will require the provision of market services and promotional efforts.
Solvable points on genus-one curves over local fields
Authors: Pál Ambrus
Published: May 2012

Let $F$ be a field complete with respect to a discrete valuation whose residue field is perfect of characteristic $p\gt 0$. We prove that every smooth, projective, geometrically irreducible curve of genus one defined over $F$ with a non-zero divisor of degree a power of $p$ has a solvable point over $F$.
A new approach to the Koszul property in representation theory using graded subalgebras
Authors: Parshall Brian J. , Scott Leonard L.
Published: May 2012

Given a quasi-hereditary algebra $B$, we present conditions which guarantee that the algebra $\mathrm{gr} \hspace{0.167em} B$ obtained by grading $B$ by its radical filtration is Koszul and at the same time inherits the quasi-hereditary property and other good Lie-theoretic properties that $B$ might possess. The method involves working with a pair $(A, \mathfrak{a})$ consisting of a quasi-hereditary algebra $A$ and a (positively) graded subalgebra $\mathfrak{a}$. The algebra $B$ arises as a quotient $B= A/ J$ of $A$ by a defining ideal $J$ of $A$. Along the way, we also show that the standard (Weyl) modules for $B$ have a structure as graded modules for $\mathfrak{a}$. These results are applied to obtain new information about the finite dimensional algebras (e.g., the $q$-Schur algebras) which arise as quotients of quantum enveloping algebras. Further applications, perhaps the most penetrating, yield results for the finite dimensional algebras associated with semisimple algebraic groups in positive characteristic $p$. These results require, at least at present, considerable restrictions on the size of $p$.
24GHz Digital beamforming radar with T-shaped antenna array for three-dimensional object detection
Authors: Harter Marlene , Schipper Tom , Zwirello Lukasz , Ziroff Andreas , Zwick Thomas
Published: May 2012

This paper introduces a radar system for three-dimensional (3D) object detection and imaging. The presented 3D measurement method combines the frequency-modulated continuous wave (FMCW) approach for range measurements with a multiple-input multiple-output (MIMO) technique for digital beamforming in two dimensions. With an orthogonal arrangement of the antenna arrays for transmit and receive, the angular information is obtained in azimuth and elevation without mechanical beamsteering. The proposed principle allows performing 3D imaging by means of the acquired range, azimuth, and elevation information with a minimum of required hardware. Starting from the realization of the 3D radar imaging concept, the hardware architecture and the developed prototype are discussed in detail. Furthermore, the object detection capability of the 3D imaging radar system is demonstrated by measurements. The results show that the introduced 3D measurement concept in its realization is well suited for numerous applications.
Geology of quartz and hydrated silica‐bearing deposits near Antoniadi Crater, Mars
Authors: Smith Matthew R. , Bandfield Joshua L.
Published: May 2012

The only area on Mars where crystalline quartz has been identified from orbit is near Antoniadi Crater, on the northern edge of the Syrtis Major shield volcano. However, the method of quartz formation has remained unknown. In this study, we use high‐resolution satellite imagery as well as thermal and near‐infrared spectroscopy to construct a geologic history of these deposits and their local context. We find that the quartz‐bearing deposits are consistently co‐located with hydrated silica. This spatial coherence suggests that the quartz formed as a diagenetic product of amorphous silica, rather than as a primary igneous mineral. Diagenetic quartz is a mature alteration product of hydrated amorphous silica, and indicates more persistent water and/or higher temperatures at this site. Beneath the silica‐bearing rocks, we also find spectral evidence for smectites in the lowermost exposed Noachian‐aged breccia. A similar stratigraphic sequence — smectite‐bearing breccias beneath deposits containing minerals suggesting a greater degree of alteration — has also been found at nearby exposures at Nili Fossae and Toro Crater, suggesting a widespread sequence of alteration. By merging the mineral detections of thermal infrared (quartz, feldspar) and near‐infrared spectroscopy (hydrated silica, smectite clays) we are able to construct a more complete geologic history from orbit.
Propagation of medium scale traveling ionospheric disturbances at different latitudes and solar cycle conditions
Authors: Hernández‐Pajares M. , Juan J. M. , Sanz J. , Aragón‐Àngel A.
Published: May 2012

In this work, an extension in latitude range and time span with respect previous studies on Medium Scale Traveling Ionospheric Disturbances (MSTID) propagation, is presented. So far they have been basically studied at mid latitude and for limited periods (less than few years) at solar maximum conditions. This extension has been possible due to the availability of local Global Positioning System (GPS) networks at mid‐north hemisphere (California), mid‐south hemisphere (New Zealand), high and low latitudes (Alaska and Hawaii), for the last 13, 11, 7 and 4 years respectively. Optimal algorithms specially suitable for mass data processing have been used, such as the Single Receiver Medium Scale Traveling Ionospheric activity index (SRMTID) and the phase difference method for MSTID propagation estimation. The results reveal that several of the main MSTID climatological trends at mid latitude are also shared at low and high latitude, also modulated in intensity also by the Solar Cycle. This is the case for local fall/winter day‐time equatorward propagated MSTIDs with typical velocities and wavelengths of 150–250 m/s and 100–300 km respectively. Moreover the comparison of MSTID propagation estimation using different techniques, and their implications in terms of potential origins of MSTIDs, are also discussed.
Water and solute transport along hydrological pathways
Authors: Cvetkovic Vladimir , Carstens Christoffer , Selroos Jan‐Olof , Destouni Georgia
Published: May 2012

A Lagrangian framework for material transport along hydrological pathways is presented and consequences of statistically stationary space‐time flow velocity variations on advective transport are investigated. The two specific questions addressed in this work are: How do temporal fluctuations affect forward and backward water travel time distributions when combined with spatial variability? and Can mass transfer processes be quantified using conditional probabilities in spatially and temporally variable flow? Space‐time trajectories are studied for generic conditions of flow, with fully ergodic or only spatially ergodic velocity. It is shown that forward and backward distributions of advective water travel time coincide for statistically stationary space‐time variations. Temporal variability alters the statistical structure of the Lagrangian velocity fluctuations. Once this is accounted for, integration of the memory function with the travel time distribution is applicable for quantifying retention. Further work is needed to better understand the statistical structure of space‐time velocity variability in hydrological transport, as well as its impact on tracer retention and attenuation.
Potential impacts of Asian carbon aerosols on future US warming
Authors: Teng Haiyan , Washington Warren M. , Branstator Grant , Meehl Gerald A. , Lamarque Jean‐Francois
Published: May 2012

This study uses an atmosphere‐ocean fully coupled climate model to investigate possible remote impacts of Asian carbonaceous aerosols on US climate change. We took a 21st century mitigation scenario as a reference, and carried out three sets of sensitivity experiments in which the prescribed carbonaceous aerosol concentrations over a selected Asian domain are increased by a factor of two, six, and ten respectively during the period of 2005–2024. The resulting enhancement of atmospheric solar absorption (only the direct effect of aerosols is included) over Asia induces tropospheric heating anomalies that force large‐scale circulation changes which, averaged over the twenty‐year period, add as much as an additional 0.4°C warming over the eastern US during winter and over most of the US during summer. Such remote impacts are confirmed by an atmosphere stand‐alone experiment with specified heating anomalies over Asia that represent the direct effect of the carbon aerosols.
High Vp/Vs ratio: Saturated cracks or anisotropy effects?
Authors: Wang X.‐Q. , Schubnel A. , Fortin J. , David E. C. , Guéguen Y. , Ge H.‐K.
Published: May 2012

We measured Vp/Vs ratios of thermally cracked Westerly granite, thermally cracked Carrara marble and 4% porosity Fontainebleau sandstone, for an effective mean pressure ranging from 2 to 95 MPa. Samples were fluid‐saturated alternatively with argon gas and water (5 MPa constant pore pressure). The experimental results show that at ultrasonic frequencies, Vp/Vs ratio of water saturated specimen never exceeded 2.15, even at effective mean pressure as low as 2 MPa, or for a lithology for which the Poisson's ratio of minerals is as high as 0.3 (calcite). In order to check these results against theoretical models: we examine first a randomly oriented cracked medium (with dispersion but without anisotropy); and second a medium with horizontally aligned cracks (with anisotropy but without dispersion). The numerical results show that experimental data agree well with the first model: at high frequency, Vp/Vs ratios range from 1.6 to 1.8 in the dry case and from 1.6 to 2.2 in the saturated case. The second model predicts both Vp/Sv and Vp/Sh to vary from 1.2 to 3.5, depending on the raypath angle relative to the crack fabric. In addition, perpendicular to the crack fabric, a high Vp/Vs ratio is predicted in the absence of shear wave splitting. From these results, we argue the possibility that high Vp/Vs ratio (>2.2) as recently imaged by seismic tomography in subduction zones, may come from zones presenting important crack anisotropy. The cumulative effects of crack anisotropy and high pore fluid pressure are required to get Vp/Vs ratios above 2.2.
Lunar pickup ions observed by ARTEMIS: Spatial and temporal distribution and constraints on species and source locations
Authors: Halekas J. S. , Poppe A. R. , Delory G. T. , Sarantos M. , Farrell W. M. , Angelopoulos V. , McFadden J. P.
Published: May 2012

ARTEMIS observes pickup ions around the Moon, at distances of up to 20,000 km from the surface. The observed ions form a plume with a narrow spatial and angular extent, generally seen in a single energy/angle bin of the ESA instrument. Though ARTEMIS has no mass resolution capability, we can utilize the analytically describable characteristics of pickup ion trajectories to constrain the possible ion masses that can reach the spacecraft at the observation location in the correct energy/angle bin. We find that most of the observations are consistent with a mass range of ∼20–45 amu, with a smaller fraction consistent with higher masses, and very few consistent with masses below ∼15 amu. With the assumption that the highest fluxes of pickup ions come from near the surface, the observations favor mass ranges of ∼20–24 and ∼36–40 amu. Although many of the observations have properties consistent with a surface or near‐surface release of ions, some do not, suggesting that at least some of the observed ions have an exospheric source. Of all the proposed sources for ions and neutrals about the Moon, the pickup ion flux measured by ARTEMIS correlates best with the solar wind proton flux, indicating that sputtering plays a key role in either directly producing ions from the surface, or producing neutrals that subsequently become ionized.
In vitro and in vivo studies into the biological activities of 1,10-phenanthroline, 1,10-phenanthroline-5,6-dione and its copper(ii) and silver(i) complexes
Authors: McCann Malachy , Santos André L. S. , da Silva Bianca A. , Romanos Maria Teresa V. , Pyrrho Alexandre S. , Devereux Michael , Kavanagh Kevin , Fichtner Iduna , Kellett Andrew
Published: May 2012

1,10-Phenanthroline (phen, 5), 1,10-phenanthroline-5,6-dione (phendione, 6), [Cu(phendione)3](ClO4)2·4H2O (12) and [Ag(phendione)2]ClO4 (13) are highly active, in vitro, against a range of normal and cancerous mammalian cells, fungal and insect cell lines, with the metal complexes offering a clear enhancement in activity. Cytoselectivity was not observed between the tumorigenic and non-tumorigenic mammalian lines. In in vivo tests, using Galleria mellonella and Swiss mice, all four compounds were well tolerated in comparison to the clinical agent, cisplatin. In addition, blood samples taken from the Swiss mice showed that the levels of the hepatic enzymes, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), remained unaffected. Immunocompromised nude mice showed a much lower tolerance to 13 and, subsequently, when these mice were implanted with Hep-G2 (hepatic) and HCT-8 (colon) human-derived tumors, there was no influence on tumor growth.
Sfrp5 expression and secretion in adipocytes are up‐regulated during differentiation and are negatively correlated with insulin resistance
Authors: Lv Ci , Jiang Youzhao , Wang Hui , Chen Bing
Published: May 2012

We have examined the patterns of Sfrp5 (secreted frizzled‐related protein 5) mRNA expression and protein secretion during adipocyte differentiation, and investigated the potential role of Sfrp5 in IR (insulin resistance) in adipocytes. 3T3‐L1 pre‐adipocytes were induced for differentiation, and RT—PCR (reverse transcription—PCR) and ELISA assays were used to determine Sfrp5 mRNA expression and protein secretion. The results showed that with the differentiation and maturity of pre‐adipocytes, transcription and protein secretion of Sfrp5 gradually increased, peaking on the 9th day of differentiation. Sfrp5 mRNA expression in mature adipocytes was decreased by 20, 22 and 32 upon treatment with dexamethasone, insulin and TNF (tumour necrosis factor) respectively, whereas Sfrp5 protein secretion was decreased by 15, 17 and 30%, correspondingly. In contrast, Sfrp5 mRNA expression in mature adipose was increased by 34 and 19% upon treatment with rosiglitazone and metformin respectively, whereas Sfrp5 protein secretion was increased by 10 and 6%, correspondingly. In conclusion, Sfrp5 mRNA expression and protein secretion depend on the differentiation of adipocytes. The dysregulation of Sfrp5 expression and secretion is directly correlated with IR. Up‐regulation of Sfrp5 expression and secretion in adipocytes may be one crucial mechanism by which rosiglitazone and metformin improve insulin sensitivity.
Epithelial cells in culture: injured or differentiated cells?
Authors: Baer Patrick C. , Bereiter‐Hahn Jürgen
Published: May 2012

Isolation of epithelial cells for cell culture is based on destruction of epithelial integrity. The consequences are manifold: cell polarity and specific cell functions are lost; cells acquire non‐epithelial characteristics and start to proliferate. This situation may also occur in situ when parts of the epithelium are lost, either by apoptosis or necrosis by organ or tissue injury. During recovery from this injury, surviving epithelial cells proliferate and may restore epithelial integrity and finally re‐differentiate into functional epithelial cells. In vitro, this re‐differentiation is mostly not complete due to sub‐optimal culture conditions. Therefore cultured epithelial cells resemble wounded or injured epithelia rather than healthy and well differentiated epithelia. The value of an in vitro cell model is the extent to which it helps to understand the function of the cells in situ. A variety of parameters influence the state of differentiation of cultured cells in vitro. Although each of these parameters had been studied, the picture how they co‐ordinately influence the state of differentiation of epithelial cells in vitro is incomplete. Therefore we discuss the influence of the isolation method and cell culture on epithelial cells, and outline strategies to achieve highly differentiated epithelial cells for the use as an in vitro model.
Microcavity array plasma system for remote chemical processing at atmospheric pressure
Authors: Lee Dae-Sung , Hamaguchi Satoshi , Sakai Osamu , Park Sung-Jin , Eden J Gary
Published: May 2012

A microplasma system designed for chemical processing at atmospheric pressure is fabricated and characterized with flowing He/O2 gas mixtures. At the heart of this microcavity dielectric barrier discharge (MDBD) system are two arrays of half-ellipsoidal microcavities engraved by micropowder blasting into dielectric surfaces facing a flowing, low-temperature plasma. Experiments demonstrate that the ignition voltage is reduced, and the spatially averaged optical emission is doubled, for an MDBD flowing plasma array relative to an equivalent system having no microcavities. As an example of the potential of flowing atmospheric microplasma systems for chemical processing, the decomposition of methylene blue (as evidenced by decoloration at 650.2 nm) is shown to proceed at a rate as much as a factor of two greater than that for a non-microcavity equivalent.
Structural characterization of ZnO thin films grown on various substrates by pulsed laser deposition
Authors: Novotný M , Čížek J , Kužel R , Bulíř J , Lančok J , Connolly J , McCarthy E , Krishnamurthy S , Mosnier J-P , Anwand W , Brauer G
Published: May 2012

ZnO thin films were grown by pulsed laser deposition on three different substrates: sapphire (0 0 0 1), MgO (1 0 0) and fused silica (FS). The structure and morphology of the films were characterized by x-ray diffraction and scanning electron microscopy and defect studies were carried out using slow positron implantation spectroscopy (SPIS). Films deposited on all substrates studied in this work exhibit the wurtzite ZnO structure and are characterized by an average crystallite size of 20–100 nm. However, strong differences in the microstructure of films deposited on various substrates were found. The ZnO films deposited on MgO and sapphire single-crystalline substrates exhibit local epitaxy, i.e. a well-defined relation between film crystallites and the substrate. Domains with different orientation relationships with the substrate were found in both films. On the other hand, the film deposited on the FS substrate exhibits fibre texture with random lateral orientation of crystallites. Extremely high compressive in-plane stress of σ ∼ 14 GPa was determined in the film deposited on the MgO substrate, while the film deposited on sapphire is virtually stress-free, and the film deposited on the FS substrate exhibits a tensile in-plane stress of σ ∼ 0.9 GPa. SPIS investigations revealed that the concentration of open-volume defects in the ZnO films is substantially higher than that in a bulk ZnO single crystal. Moreover, the ZnO films deposited on MgO and sapphire single-crystalline substrates exhibit a significantly higher density of defects than the film deposited on the amorphous FS substrate.
Impact of extended defects on Hall and magnetoresistivity effects in cubic silicon carbide
Authors: Vasiliauskas R , Mekys A , Malinovskis P , Juillaguet S , Syväjärvi M , Storasta J , Yakimova R
Published: May 2012

From magnetoresistivity effect measurements the carrier mobility at room temperature is found to be 200 cm2 V−1 s−1 in heteroepitaxially grown 3C-SiC on 6H-SiC by sublimation epitaxy. The main scattering mechanisms are found to be scattering by neutral impurities at low temperatures and by phonons at higher temperatures. The carrier concentration is in the range of 1016 cm−3, which corresponds to the concentration of residual doping by nitrogen acquired from photoluminescence measurements. Using magnetoresistance and Hall mobility data we have created a simple model which quantifies the volume of the samples influenced by extended defects. A higher doping near extended defects is either not present in the samples or might be screened by the electrostatic field created by these defects.
Secondary fluorescence in electron probe microanalysis of material couples
Authors: Llovet X , Pinard P T , Donovan J J , Salvat F
Published: May 2012

We describe a semi-analytical method for the fast calculation of secondary fluorescence in electron probe microanalysis of material couples. The calculation includes contributions from primary K-, L- and M-shell characteristic x-rays and bremsstrahlung photons. The required physical interaction parameters (subshell partial cross sections, attenuation coefficients, etc) are extracted from the database of the Monte Carlo simulation code system PENELOPE. The calculation makes use of the intensities of primary photons released in interactions of beam electrons and secondary electrons. Since these intensities are not readily available and do not allow analytical calculation, they are generated from short Monte Carlo simulation runs. The reliability of the proposed calculation method has been assessed by comparing calculated, distance-dependent k-ratios with experimental data available in the literature and with results from simulations with PENELOPE. Numerical results are found to be in close agreement with both simulated and experimental data.
Progress in characterization and modelling of the current ramp-up phase of ASDEX Upgrade discharges
Authors: Fable E. , Angioni C. , Fischer R. , Geiger B. , McDermott R.M. , Pereverzev G.V. , Puetterich T. , Ryter F. , Scott B. , Tardini G. , Viezzer E.
Published: May 2012

Measurements of plasma core impurity ion temperature and toroidal rotation are obtained during the current ramp-up phases of plasma discharges in the ASDEX Upgrade tokamak, by means of charge exchange recombination spectroscopy utilizing short neutral beam injected blips. The phenomenology of these profiles as the current is varied is presented. The observations are reported for both ohmically heated and electron cyclotron heating assisted ramps, with auxiliary heating applied both on-axis and off-axis. The evolution of global parameters is also reported. A comparison between ion and electron kinetic profiles evolution is made. Power balance analysis is performed to establish the local confinement properties and their evolution during the current ramp. Transport modelling of several cases with a theory-based model is carried out and a recipe, which involves edge-relevant parameters, is proposed to account for the transport in the outer plasma region. Finally, linear gyrokinetic calculations of dominant microinstabilities allow us to correlate the observed transport with the background turbulence regime.
Plasma profile evolution during disruption mitigation via massive gas injection on MAST
Authors: Thornton A.J. , Gibson K.J. , Chapman I.T. , Harrison J.R. , Kirk A. , Lisgo S.W. , Lehnen M. , Martin R. , Scannell R. , Cullen A.
Published: May 2012

Massive gas injection (MGI) is one means of ameliorating disruptions in future devices such as ITER, where the stored energy in the plasma is an order of magnitude larger than in present-day devices. The penetration of the injected impurities during MGI in MAST is diagnosed using a combination of high-speed (20 kHz) visible imaging and high spatial (1 cm) and temporal (0.1 ms) resolution Thomson scattering (TS) measurements of the plasma temperature and density. It is seen that the rational surfaces, in particular q = 2, are the critical surfaces for disruption mitigation. The TS data shows the build-up of density on rational surfaces in the edge cooling period of the mitigation, leading to the collapse of the plasma in a thermal quench. The TS data are confirmed by the visible imaging, which shows filamentary structures present at the start of the thermal quench. The filamentary structures have a topology which matches that of a q = 2 field line in MAST, suggesting that they are located on the q = 2 surface. Linearized magnetohydrodynamic stability analysis using the TS profiles suggests that the large density build-up on the rational surfaces drives modes within the plasma which lead to the thermal quench. The presence of such modes is seen experimentally in the form of magnetic fluctuations on Mirnov coils and the growth of an n = 1 toroidal mode in the period prior to the thermal quench. These results support the observations of other machines that the 2/1 mode is the likely trigger for the thermal quench in a mitigated disruption and suggests that the mitigation process in spherical tokamaks is similar to that in conventional aspect ratio devices.
Scrape-off layer ion acceleration during fast wave injection in the DIII-D tokamak
Authors: Pace D.C. , Pinsker R.I. , Heidbrink W.W. , Fisher R.K. , Van Zeeland M.A. , Austin M.E. , McKee G.R. , García-Muñoz M.
Published: May 2012

Fast wave injection is employed on the DIII-D tokamak as a current drive and electron heating method. Bursts of energetic ions with energy E
o > 20 keV are observed immediately following fast wave injection in experiments featuring the 8th ion cyclotron harmonic near the antenna. Using the energy and pitch angle of the energetic ion burst as measured by a fast-ion loss detector, it is possible to trace the origin of these ions to a particular antenna. The ion trajectories exist entirely within the scrape-off layer. These observations are consistent with the presence of parametric decay instabilities near the antenna strap. It is suggested that the phase space capabilities of the loss detector diagnostic can improve studies of wave injection coupling and efficiency in tokamaks by directly measuring the effects of parametric decay thresholds.
Increased Rho kinase activity in congestive heart failure
Authors: Dong Ming , Liao James K. , Fang Fang , Lee Alex Pui‐Wai , Yan Bryan Ping‐Yen , Liu Ming , Yu Cheuk‐Man
Published: May 2012

Aims

Rho kinases (ROCKs) are the best characterized effectors of the small G‐protein RhoA, and play a role in enhanced vasoconstriction in animal models of congestive heart failure (CHF). This study examined if ROCK activity is increased in CHF and how it is associated with the outcome in CHF.

Methods and results

Patients admitted with CHF (n =178), disease controls (n =31), and normal subjects (n =30) were studied. Baseline ROCK activity was measured by phosphorylation of themyosin‐binding subunit in peripheral leucocytes. The patients were followed up for 14.4 ± 7.2 months (range 0.5–26 months) or until the occurrence of cardiac death. The ROCK activity in CHF patients (2.93 ± 0.87) was significantly higher than that of the disease control (2.06 ± 0.38, P < 0.001) and normal control (1.57 ± 0.43, P < 0.001) groups. Similarly, protein levels of ROCK1 and ROCK2 as well as the activity of RhoA in CHF were significantly higher than in disease controls and normal controls (all P < 0.05). Dyspnoea at rest (β =0.338, P < 0.001), low left ventricular ejection fraction (β = –0.277, P < 0.001), and high creatinine (β =0.202, P =0.006) were independent predictors of the baseline ROCK activity in CHF. Forty‐five patients died within 2 years follow‐up (25.3%). Combining ROCK activity and N‐terminal pro brain natriuretic peptide (NT‐proBNP) had an incremental value (log rank χ2 =11.62) in predicting long‐term mortality when compared with only NT‐proBNP (log rank χ2 =5.16, P < 0.05).

Conclusion

ROCK activity is increased in CHF and it might be associated with the mortality in CHF. ROCK activity might be a complementary biomarker to CHF risk stratification.
Acute effect of percutaneous MitraClip therapy in patients with haemodynamic decompensation
Authors: Biner Simon , Siegel Robert J. , Feldman Ted , Rafique Asim M. , Trento Alfredo , Whitlow Patrick , Rogers Jason , Moon Marc , Lindman Brian , Zajarias Alan , Glower Donald , Kar Saibal ,   on behalf of the EVEREST investigators
Published: May 2012

Aims

To evaluate the haemodynamic effect of acute procedural success (APS) after MitraClip therapy in patients with haemodynamic decompensation.

Methods and results

Of 107 patients, 79 achieved APS after MitraClip implantation. The increase in cardiac index (CI) was primarily detected in patients with a low baseline CI (2.0 ± 0.5 to 2.5 ± 5 L/min/m2, P < 0.001). There was a decrease in left ventricular end‐diastolic pressure (LVEDP) (20 ± 5 to 13 ± 5 mmHg, P = 0.002) and mean pulmonary capillary wedge pressure (PCWPm) (20 ± 4 to 16 ± 5 mmHg, P = 0.001) in patients with values >15 mmHg at baseline, and a decrease in mean pulmonary artery systolic (PAPm) (36 ± 4 to 29 ± 7 mmHg P = 0.003) in those with values >30 mmHg before the MitraClip procedure. Patients with decompensation compared with patients with compensation experienced significant reduction in LVEDP (–8.3 ± 11.9 mmHg vs. –0.2 ± 4.5 mmHg, P = 0.009), a reduction in PCWPm (–3.5 ± 5.6 mmHg vs. 1.9 ± 4.7 mmHg, P < 0.001), and a reduction in PAPm (–8 ± 9 mmHg vs. 3 ± 6 mmHg, P < 0.001).

Conclusion

The favourable haemodynamic effects of MitraClip therapy on CI were primarily detected in patients with low CI before the procedure, and improvements in left‐sided filling pressure and PAP were primarily seen in those with elevated values at baseline.
A Second Spore Stage Confirmed for Apioplagiostoma populi, the Causal Agent of Bronze Leaf Disease of Populus in Minnesota
Authors: Ostry M. E. , Moore M. J. , Anderson N. A.
Published: May 2012

Bronze leaf disease (BLD) affects several Populus species in North America but is particularly damaging to hybrids in section Populus (4). BLD, caused by the fungus Apioplagiostoma populi (syn. Plagiostoma populi) described by Cash and Waterman (1), takes its name from the characteristic dark purple to brown pigmentation of infected leaves. A. populi has not been cultured on artificial media either from diseased tissues or cast ascospores. An anamorph has not been conclusively identified but spores from blister-like acervuli on symptomatic leaves have been suggested to function as spermatia (3). In an attempt to describe the imperfect stage of A. populi, collections of diseased leaves of P. alba × sieboldii and P. alba × grandidentata‘Crandon’ growing in a plantation near Rosemount, MN, were made on September 14, 2011 (leaves attached to shoots, rolled inward), October 12, 2011 (leaves attached or on the ground, tightly rolled inward), and November 1, 2011 (most leaves on the ground), and examined in the laboratory for fungal development. Leaf laminae from the September 14 collection were uniformly covered with erumpent, subcuticular blister-like acervuli on the adaxial surface only, containing unicellular, colorless spores ranging in size from 2.2 to 10.0 × 2.0 to 5.0 μm (mean 3.6 × 6.2 μm) (n = 100). Attempts to germinate and obtain cultures from these spores on common artificial media were unsuccessful. On leaves collected October 12, the blister-like acervuli were predominantly empty or releasing spores and immature perithecia of A. populi were present. Leaves collected on November 1 contained immature perithecia but were heavily colonized by surface saprophytic fungi and no intact blister-like acervuli were present. DNA was extracted from bulked samples of spores removed from the blister-like acervuli in leaves from multiple trees collected on September 14 using the DNeasy Plant Mini Kit (Qiagen Sciences, Germantown, MD). The internal transcribed spacer (ITS2) region of rDNA was PCR amplified and sequenced with primers ITS3 and ITS4. BLASTn searches revealed that sequences from three independent bulked samples were homologous (99% identity, 353 of 355 nucleotides) to A. populi from isolated perithecia (GenBank Accession No. GU205341) (2). The inability of the spores to germinate, the timing of their development and release, and the tight, inward roll of infected leaves facilitating their spread across the upper leaf surface suggest that these spores function as spermatia in the life cycle of A. populi and the blister-like acervuli in which they develop are spermogonia.

References: (1) E. K. Cash and A. M. Waterman. Mycologia 49:756, 1957. (2) L. M. Kawchuk et al. Plant Disease 94:377, 2010. (3) W. A. Sinclair and H. H. Lyon, Comstock Publishing Associates, Cornell University Press, Ithaca, NY, 2005. (4) J. A. Smith et al. Plant Disease 86:462, 2002.
Testing the Link between Sympathetic Efferent and Sensory Afferent Fibers in Neuropathic Pain
Authors: Raja Srinivasa N. , Treede Rolf-Detlef , Warner David S.
Published: May 2012

The diagnosis of sympathetically maintained pain (SMP) is typically established by assessment of pain relief during local anesthetic blockade of the sympathetic ganglia that innervate the painful body part. To determine if systemic α-adrenergic blockade with phentolamine can be used to diagnose SMP, we compared the effects on pain of local anesthetic sympathetic ganglion blocks (LASB) and phentolamine blocks (PhB) in 20 patients with chronic pain and hyperalgesia that were suspected to be sympathetically maintained. The blocks were done inrandom order on separate days. Patients rated the intensity of ongoing and stimulus-evoked pain every 5 min before, during, and after the LASB and PhB. Patients and the investigator assessing pain levels were blinded to the time of intravenous administration of phentolamine (total dose 25-35 mg). The pain relief achieved by LASB and PhB correlated closely (r = 0.84), and there was no significant difference in the maximum pain relief achieved with the two blocks (t = 0.19, P > 0.8). Nine patients experienced a greater than 50% relief of pain and hyperalgesia from both LASB and PhB and were considered to have a clinically significant component of SMP. We conclude that α-adrenergic blockade with intravenous phentolamine is a sensitive alternative test to identify patients with SMP.
Quantifying limits to detection of early warning for critical transitions
Authors: Boettiger Carl , Hastings Alan
Published: May 2012

Catastrophic regime shifts in complex natural systems may be averted through advanced detection. Recent work has provided a proof-of-principle that many systems approaching a catastrophic transition may be identified through the lens of early warning indicators such as rising variance or increased return times. Despite widespread appreciation of the difficulties and uncertainty involved in such forecasts, proposed methods hardly ever characterize their expected error rates. Without the benefits of replicates, controls or hindsight, applications of these approaches must quantify how reliable different indicators are in avoiding false alarms, and how sensitive they are to missing subtle warning signs. We propose a model-based approach to quantify this trade-off between reliability and sensitivity and allow comparisons between different indicators. We show these error rates can be quite severe for common indicators even under favourable assumptions, and also illustrate how a model-based indicator can improve this performance. We demonstrate how the performance of an early warning indicator varies in different datasets, and suggest that uncertainty quantification become a more central part of early warning predictions.
Disentangling the influence of parasite genotype, host genotype and maternal environment on different stages of bacterial infection in
Daphnia magna
Authors: Hall Matthew D. , Ebert Dieter
Published: May 2012

Individuals naturally vary in the severity of infectious disease when exposed to a parasite. Dissecting this variation into genetic and environmental components can reveal whether or not this variation depends on the host genotype, parasite genotype or a range of environmental conditions. Complicating this task, however, is that the symptoms of disease result from the combined effect of a series of events, from the initial encounter between a host and parasite, through to the activation of the host immune system and the exploitation of host resources. Here, we use the crustacean
Daphnia magna
and its parasite
Pasteuria ramosa
to show how disentangling genetic and environmental factors at different stages of infection improves our understanding of the processes shaping infectious disease. Using compatible host–parasite combinations, we experimentally exclude variation in the ability of a parasite to penetrate the host, from measures of parasite clearance, the reduction in host fecundity and the proliferation of the parasite. We show how parasite resistance consists of two components that vary in environmental sensitivity, how the maternal environment influences all measured aspects of the within-host infection process and how host–parasite interactions following the penetration of the parasite into the host have a distinct temporal component.
Complex effects of temperature on mosquito immune function
Authors: Murdock C. C. , Paaijmans Krijn P. , Bell Andrew S. , King Jonas G. , Hillyer Julián F. , Read Andrew F. , Thomas Matthew B.
Published: May 2012

Over the last 20 years, ecological immunology has provided much insight into how environmental factors shape host immunity and host–parasite interactions. Currently, the application of this thinking to the study of mosquito immunology has been limited. Mechanistic investigations are nearly always conducted under one set of conditions, yet vectors and parasites associate in a variable world. We highlight how environmental temperature shapes cellular and humoral immune responses (melanization, phagocytosis and transcription of immune genes) in the malaria vector,
Anopheles stephensi. Nitric oxide synthase
expression peaked at 30°C,
cecropin
expression showed no main effect of temperature and humoral melanization, and phagocytosis and
defensin
expression peaked around 18°C. Further, immune responses did not simply scale with temperature, but showed complex interactions between temperature, time and nature of immune challenge. Thus, immune patterns observed under one set of conditions provide little basis for predicting patterns under even marginally different conditions. These quantitative and qualitative effects of temperature have largely been overlooked in vector biology but have significant implications for extrapolating natural/transgenic resistance mechanisms from laboratory to field and for the efficacy of various vector control tools.
Chronic contamination decreases disease spread: aDaphnia–fungus–copper case study
Authors: Civitello David J. , Forys Philip , Johnson Adam P. , Hall Spencer R.
Published: May 2012

Chemical contamination and disease outbreaks have increased in many ecosystems. However, connecting pollution to disease spread remains difficult, in part, because contaminants can simultaneously exert direct and multi-generational effects on several host and parasite traits. To address these challenges, we parametrized a model using a zooplankton–fungus–copper system. In individual-level assays, we considered three sublethal contamination scenarios: no contamination, single-generation contamination (hosts and parasites exposed only during the assays) and multi-generational contamination (hosts and parasites exposed for several generations prior to and during the assays). Contamination boosted transmission by increasing contact of hosts with parasites. However, it diminished parasite reproduction by reducing the size and lifespan of infected hosts. Multi-generational contamination further reduced parasite reproduction. The parametrized model predicted that a single generation of contamination would enhance disease spread (via enhanced transmission), whereas multi-generational contamination would inhibit epidemics relative to unpolluted conditions (through greatly depressed parasite reproduction). In a population-level experiment, multi-generational contamination reduced the size of experimental epidemics but did not affectDaphniapopulations without disease. This result highlights the importance of multi-generational effects for disease dynamics. Such integration of models with experiments can provide predictive power for disease problems in contaminated environments.