bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Defects Generated by Standard- and Plasma-Implantation of Nitrogen Atoms in 4H-SiC Epitaxial Layers
Authors: Ottaviani Laurent , Kazan Michel , Biondo Stephane , Tuomisto Filip , Milesi Frédéric , Duchaine Julian , Torregrosa Frank , Palais Olivier
Published: July 2012

A comparison is made between two kinds of Nitrogen implantations for the formation of thin n+p junctions in p-type Silicon Carbide (SiC) epitaxial layers. The standard beam ion implantations and PULSIONTM processes were performed at two distinct energies (700 eV and 7 keV) and the subsequent annealing was held at 1600°C in a resistive furnace specifically adapted to SiC material. Positron Annihilation Spectroscopy (PAS) and unpolarized infrared reflectivity (IR) measurements were carried out before and after the annealing, respecively. Despite the presence of deep vacancy clusters near the as-implanted sample surfaces, no extended defects were detected after the annealing. Plasma implanted samples prove to contain a lower point defect concentration than beam implanted samples. The concentration of these defects (resulting from plasma process) is higher in the plane parallel to the optical axis, which denotes an energy spreading alongside the dopant distribution.
The Effect of the Indenter Orientation on the Formation of Dislocations and Cracks in (0001) GaN Bulk Crystals
Authors: Ratschinski Ingmar , Leipner Hartmut S. , Heyroth Frank , Fränzel Wolfgang , Leibiger Gunnar , Habel Frank
Published: July 2012

(0001) GaN bulk crystals with a thickness of 3.4 mm and a density of in-grown dislocations of 3.5·106cm-2have been deformed at room temperature using a Vickers indenter at two different sample orientations in relation to the indenter. Dislocations and cracks at the indentations were investigated by means of optical microscopy and scanning electron microscopy in secondary electron contrast and cathodoluminescence imaging. The arrangement of indentation-induced dislocations and cracks is described and the orientation effect is discussed.
Threading Dislocations in 4H-SiC Observed by Double-Crystal X-Ray Topography
Authors: Yamaguchi Hirotaka , Matsuhata Hirofumi
Published: July 2012

Threading dislocations in 4H-SiC wafer were observed by using a double crystal X-ray topography technique. The incident beam was collimated by the first crystal so that the angular divergence was reduced to sufficiently smaller than the rocking curve of a diffraction of the specimen (the second crystal). At off-Bragg angles, cross-sectional projection of threading dislocations appeared on the topographic images. From these results, we found that outcrops of the screw dislocation at the wafer surfaces suffered from significant strain, giving strong contrast on the topograph even under the condition, $\vec{g}\cdot\vec{b}=0$. In addition, the edge and screw components in the mixed dislocations were clearly distinguished.
Characterization of Dislocations in GaN Thin Film and GaN/AlN Multilayer
Authors: Ohmori Noriko , Uchimaru Tomonori , Fujimori Hiroyuki , Komiyama Jun , Abe Yoshihisa , Suzuki Shunichi
Published: July 2012

The dislocations in GaN thin film with GaN/AlN multilayer (ML) as the buffer layer were evaluated using transmission electron microscopy. A high density of dislocations parallel to the GaN/ML interface and a sudden decrease in the dislocation density at the GaN/ML interface were found. Dislocation propagation in the direction parallel to the GaN/ML interface by turning horizontally on the GaN/ML interface is considered to be effective in decreasing the dislocation density at the top layer of GaN.
Secretory Leukocyte Proteinase Inhibitor-Competent DNA Deposits Are Potent Stimulators of Plasmacytoid Dendritic Cells: Implication for Psoriasis
Authors: Skrzeczynska-Moncznik Joanna , Wlodarczyk Agnieszka , Zabieglo Katarzyna , Kapinska-Mrowiecka Monika , Marewicz Ewa , Dubin Adam , Potempa Jan , Cichy Joanna
Published: July 2012

Secretory leukocyte proteinase inhibitor (SLPI) is a well-established inhibitor of serine proteases such as human neutrophil elastase (HNE) and a NF-κB regulatory agent in immune cells. In this paper, we report that SLPI plays a previously uncharacterized role in regulating activation of plasmacytoid dendritic cells (pDCs). As the main source of IFN type I (IFNI), pDCs are crucial contributors to inflammatory and likely wound-healing responses associated with psoriasis. The mechanisms responsible for activation of pDCs in psoriatic skin are therefore of substantial interest. We demonstrate that in lesional skin of psoriasis patients, SLPI together with its enzymatic target HNE and DNA, is a component of neutrophil extracellular traps (NETs). Whereas SLPI+ neutrophils and NETs were found to colocalize with pDCs in psoriatic skin, a mixture of SLPI with neutrophil DNA and HNE induced a marked production of IFNI by pDCs. IFNI synthesis by stimulated pDCs was dependent on intracellular DNA receptor TLR9. Thus, SLPI may contribute to psoriasis by enabling pDCs to sense extracellular DNA and produce IFNI.
Loss of the Oxygen Sensor PHD3 Enhances the Innate Immune Response to Abdominal Sepsis
Authors: Kiss Judit , Mollenhauer Martin , Walmsley Sarah R. , Kirchberg Johanna , Radhakrishnan Praveen , Niemietz Thomas , Dudda Johanna , Steinert Gunnar , Whyte Moira K. B. , Carmeliet Peter , Mazzone Massimiliano , Weitz Jürgen , Schneider Martin
Published: July 2012

Hypoxia and HIFs (HIF-1α and HIF-2α) modulate innate immune responses in the setting of systemic inflammatory responses and sepsis. The HIF prolyl hydroxylase enzymes PHD1, PHD2 and PHD3 regulate the mammalian adaptive response to hypoxia; however, their significance in the innate immune response has not been elucidated. We demonstrate in this study that deficiency of PHD3 (PHD3−/−) specifically shortens the survival of mice subjected to various models of abdominal sepsis because of an overwhelming innate immune response, leading to premature organ dysfunction. By contrast, this phenotype was absent in mice deficient for PHD1 (PHD1−/−) or PHD2 (PHD2+/−). In vivo, plasma levels of proinflammatory cytokines were enhanced, and recruitment of macrophages to internal organs was increased in septic PHD3-deficient mice. Reciprocal bone marrow transplantation in sublethally irradiated mice revealed that enhanced susceptibility of PHD3-deficient mice to sepsis-related lethality was specifically caused by loss of PHD3 in myeloid cells. Several in vitro assays revealed enhanced cytokine production, migration, phagocytic capacity, and proinflammatory activation of PHD3-deficient macrophages. Increased proinflammatory activity of PHD3-deficient macrophages occurred concomitantly with enhanced HIF-1α protein stabilization and increased NF-κB activity, and interference with the expression of HIF-1α or the canonical NF-κB pathway blunted their proinflammatory phenotype. It is concluded that impairment of PHD3 enzyme function aggravates the clinical course of abdominal sepsis via HIF-1α– and NF-κB–mediated enhancement of the innate immune response.
Convolution of Trace Class Operators over Locally Compact Quantum Groups
Authors: Hu Zhiguo , Neufang Matthias , Ruan Zhong-Jin
Published: July 2012

We study locally compact quantum groups 𝔾 through the convolution algebras L1(𝔾) and (T(L2(𝔾)); ⊳). We prove that the reduced quantum groupC*-algebraC0(𝔾) can be recovered fromthe convolution ⊳ by showing that the right T(L2(𝔾))-module 〈K(L2(𝔾)) ⊳ T(L2(𝔾))〉 is equal to C0(𝔾). On the other hand, we show that the left T(L2(𝔾)(-module 〈T(L2(𝔾)) ⊳ K(L2(𝔾))〉 is isomorphic to the reduced crossed product C0(Ĝ ) r⋉C0(𝔾), and hence is a much larger C*-subalgebra of B(L2(𝔾)).

We establish a natural isomorphism between the completely bounded right multiplier algebras of L1(𝔾) and (T(L2(𝔾)); ⊳), and settle two invariance problems associated with the representation theorem of Junge–Neufang–Ruan (2009). We characterize regularity and discreteness of the quantum group 𝔾 in terms of continuity properties of the convolution . on T(L2(𝔾))⊳and settle two invariance problems associated with the representation theorem of Junge–Neufang–Ruan (2009). We characterize regularity and discreteness of the quantum group 𝔾 in terms of continuity properties of the convolution ⊳ on T(L2(𝔾)). We prove that if 𝔾 is semiregular, then the space 〈T(L2(𝔾)) ⊳ B(L2(𝔾))〉 of right 𝔾-continuous operators on L2(𝔾), which was introduced by Bekka (1990) for L1(𝔾), is a unital C*-subalgebra of B(L2(𝔾)). In the representation framework formulated by Neufang–Ruan–Spronk (2008) and Junge–Neufang–Ruan, we show that the dual properties of compactness and discreteness can be characterized simultaneously via automatic normality of quantum group bimodule maps on B(L2(𝔾)). We also characterize some commutation relations of completely bounded multipliers of (T(L2(𝔾)); ⊳) over B(L2(𝔾)).
Market-Driven Management, Competitive Space and Global Networks
Authors: Brondoni Silvio M.
Published: July 2012

Firms compete today in a situation of intense rivalry, in global markets that are subject to political, social and technological instability. As a result, no company can rely only on its own resources, knowledge and skills as it did in the past. Global managerial economics demands ramified, widespread and strongly interrelated organisations (networks). These complex structures favour managerial capabilities and outsourcing relations with co-makers and external partners (competitive alliances). The corporate culture therefore evolves into cross-cultural management, designed to overcome the physical limits of competition (marketspace management) and the local environment. In global markets, a network corporate culture makes it possible to create organisations with uniform structures, stimulated and checked by a system of communications networks (Internet; Intranet; Extranet), and it presupposes different levels of performance evaluation, which envisage an estimate of the strategic harmonisation (chairman leadership) and of operating armonisation (management leadership).
Push and Pull Policy in Market-Driven Management
Authors: Corniani Margherita
Published: July 2012

Push and pull policies identify the different logics that underpin the relationship between a business and its final demand. Push policy refers to the development of processes that emanate from the company and go towards the market, while pull policy refers to processes that start from the market and go towards the company. Push and pull policies identify processes regarding project, production and distribution activities but also communication flows. This two policies differ for costs, and for their ability to adapt to the various competitive dynamics. In global dynamic markets, in over supply conditions, push and pull policies can be integrated to maximize the advantages of scale and the competitiveness of fast and personalized market reactions.
Market-Driven Management, Competitive Markets and Performance Metrics
Authors: Garbelli Maria Emilia
Published: July 2012

Metrics are performance indicators used to indicate, measure or record values of a particular magnitude. Metrics, seen as overall indicators of corporate performance, are one of the fundamental tools used to monitor and orient corporate management. They can be classified by: financial–non-financial; quantitative–qualitative; accounting–nonaccounting; internal and external; process and end result. Metrics can serve a dual purpose: to provide elements for assessment, inside the company environment; to provide evaluation parameters outside the company.
From Brand Management to Global Business Management in Market-Driven Companies
Authors: Zito Emilio
Published: July 2012

Over the past several years, the most competitive mass-market companies (automobile, high-tech, consumer and retail, etc.) have been experiencing a new strategic approach around the concept of Market-Driven strategy, as opposed to a pure marketing-focused approach known as Customer-Driven strategy. A fast-moving, mass-market global company would likely have a precise performance measurement system in place with broad performance indicators based on: project economics, ratios analysis (ROI, inventory turnover, etc.), risk management, shareholders’ value analysis, synergies forecasts (economies of scale, scope, learning, etc.), market share, customer and retailer satisfaction. Therefore, the management structure will be focused on brand and product global strategies involving a new type of operational manager: the global business manager.
Capitalism and Sustainable Development
Authors: Lambin Jean-Jacques
Published: July 2012

The crisis has shattered confidence in the public opinion on the capacity of the capitalist system to regulate itself to avoid catastrophic situations as presently observed in the world. The question is to know whether the capitalist system will be able to evolve toward a business model compatible with the objective of sustainable development. To the firm, the challenge is formidable: how to conciliate the profitability imperative with the necessity to reduce waste, pollution and carbon emissions? The models of a loop economy and of a functional service economy are complementary and propose new business models promising solutions for developing an eco-responsible capitalism.
Ouverture de ‘Marketing Channels and Global Markets’
Authors: Brondoni Silvio M. , Musso Fabio
Published: July 2012

An over-supply condition and the global markets favour a ‘widespread selectivity’ of consumption, and they require, on the one hand, new rules for competition between manufacturers, and on the other, they also stimulate new marketing channels strategies, as an economic and relational entity as a whole. From this point of view, it is important first analyse some key issues relating to marketing channels, and then focusing attention on certain aspects, such as innovation, the impact of technology on the consumer buying process and on his own buying habits, and finally the extension of the retailers offer to non-core services, particularly financial services.
Innovation in Marketing Channels
Authors: Musso Fabio
Published: July 2012

In more recent years, the context of globalization in which market channel structures and strategies are developing is bringing to a more complex concept of marketing channels, with disintermediation or reintermediation, multichanneling and new roles/specializations that are emerging as new issues. In this context, innovation in marketing channels becomes a complex, multiorganizational, multidisciplinary activity that requires collaboration and interactions across various entities within the supply chain network. In recent years, the innovation processes in marketing channels have occurred with high intensity and speed, especially following the changes spurred by technology that allowed the adoption of more efficient organizational solutions.
Large Retailers’ Financial Services
Authors: Risso Mario
Published: July 2012

Over the last few years, large retailers offering financial services have considerably grown in the financial services sector. Retailers are increasing the wideness and complexity of their offer of financial services. Large retail companies provide financial services to their customers following different strategic ways. The provision of financial services in the retailers offer is implemented in several different ways related to the strategies, the structures and the degree of financial know-how of the large retailers involved.
Intangibles, Global Networks & Corporate Social Responsibility
Authors: Brondoni Silvio M.
Published: July 2012

Network organisations emphasise the importance of corporate and product intangible assets. In global competition, the managerial economics of intangibles imposes new network policies of corporate social responsibility, dominated by global social issues such as economic sustainability, eco-responsibility, worker protection and so on.
Market-Driven Management and Intangible Assets in Global Television Set Manufacturers
Authors: Silvestrelli Patrizia
Published: July 2012

The television set industry is a global sector where the most competitive companies are market-driven. Their competitive advantage is based not only on their ability to innovate products but also on their capability to develop and strengthen intangible assets, such as corporate culture, brand image and relationships between organisations.
Momentum and scalar transport within a vegetation canopy following atmospheric stability and seasonal canopy changes: the CHATS experiment
Authors: Dupont S. , Patton E. G.
Published: July 2012

Abstract. Momentum and scalar (heat and water vapor) transfer between a walnut canopy and the overlying atmosphere are investigated for two seasonal periods (before and after leaf-out), and for five thermal stability regimes (free and forced convection, near-neutral condition, transition to stable, and stable). Quadrant and octant analyses of momentum and scalar fluxes followed by space-time autocorrelations of observations from the Canopy Horizontal Array Turbulence Study's (CHATS) thirty meter tower help characterize the motions exchanging momentum, heat, and moisture between the canopy layers and aloft. During sufficiently windy conditions, i.e. in forced convection, near-neutral and transition to stable regimes, momentum and scalars are generally transported by sweep and ejection motions associated with the well-known canopy-top "shear-driven" coherent eddy structures. During extreme stability conditions (both unstable and stable), the role of these "shear-driven" structures in transporting scalars decreases, inducing notable dissimilarity between momentum and scalar transport. In unstable conditions, "shear-driven" coherent structures are progressively replaced by "buo-yantly-driven" structures, known as thermal plumes; which appear very efficient at transporting scalars, especially upward thermal plumes above the canopy. Within the canopy, downward thermal plumes become more efficient at transporting scalars than upward thermal plumes if scalar sources are located in the upper canopy. We explain these features by suggesting that: (i) downward plumes within the canopy correspond to large downward plumes coming from above, and (ii) upward plumes within the canopy are local small plumes induced by canopy heat sources where passive scalars are first injected if there sources are at the same location as heat sources. Above the canopy, these small upward thermal plumes aggregate to form larger scale upward thermal plumes. Furthermore, scalar quantities carried by downward plumes are not modified when penetrating the canopy and crossing upper scalar sources. Consequently, scalars appear to be preferentially injected into upward thermal plumes as opposed to in downward thermal plumes. In stable conditions, intermittent downward and upward motions probably related to elevated shear layers are responsible for canopy-top heat and water vapor transport through the initiation of turbulent instabilities, but this transport remains small. During the foliated period, lower-canopy heat and water vapor transport occurs through thermal plumes associated with a subcanopy unstable layer.
DOAS measurements of formaldehyde and glyoxal above a south-east Asian tropical rainforest
Authors: MacDonald S. M. , Oetjen H. , Mahajan A. S. , Whalley L. K. , Edwards P. M. , Heard D. E. , Jones C. E. , Plane J. M. C.
Published: July 2012

Abstract. Tropical rainforests act as a huge contributor to the global emissions of biogenic volatile organic compounds (BVOCs). Measurements of their oxidation products, such as formaldehyde (HCHO) and glyoxal (CHOCHO), provide useful indicators of fast photochemistry occurring in the lower troposphere. However, measurements of these species in tropical forest locations are extremely limited. To redress this, HCHO and CHOCHO were measured using the long-path (LP) and multi-axis (MAX) differential optical absorption spectroscopy (DOAS) techniques above the rainforest canopy in Borneo during two campaigns in spring and summer 2008, as part of the Oxidant and Particle Photochemical Processes above a south-east Asian tropical rainforest (OP3) project. The results were compared with concurrent measurements of hydroxyl radical (OH), isoprene (C5H8) (which was the dominant organic species emitted in this forest environment), and various meteorological parameters. Formaldehyde was observed at a maximum concentration of 4.5 ppb and glyoxal at a maximum of 1.6 ppb, significantly higher than previous measurements in rural locations. A 1-D chemistry model was then used to assess the diurnal evolution of formaldehyde and glyoxal throughout the boundary layer. The results, which compare well with the LP-DOAS and MAX-DOAS observations, suggest that the majority of the glyoxal and formaldehyde is confined to the first 500 m of the boundary layer, and that the measured ratio of these species is reproduced using currently accepted product yields for the oxidation of isoprene by OH. An important conclusion is that the measured levels of glyoxal are consistent with the surprisingly high concentrations of OH measured in this environment.
Overview of the 2007 and 2008 campaigns conducted as part of the Greenland Summit Halogen-HOx Experiment (GSHOX)
Authors: Thomas J. L. , Dibb J. E. , Stutz J. , von Glasow R. , Brooks S. , Huey L. G. , Lefer B.
Published: July 2012

Abstract. From 10 May through 17 June, 2007 and 6 June through 9 July, 2008 intensive sampling campaigns at Summit, Greenland confirmed that active bromine chemistry is occurring in and above the snow pack at the highest part of the Greenland ice sheet (72°36' N, 38° 25' W and 3.2 km a.s.l.). Direct measurements found BrO and soluble gas phase Br− mixing ratios in the low pptv range on many days (maxima <10 pptv). Conversion of up to 200 pg m−3 of gaseous elemental mercury (GEM) to reactive gaseous mercury (RGM) and enhanced OH relative to HO2 plus RO2 confirm that active bromine chemistry is impacting chemical cycles even at such low abundances of reactive bromine species. However, it does not appear that Bry chemistry can fully account for observed perturbations to HOx partitioning, suggesting unknown additional chemical processes may be important in this unique environment, or that our understanding of coupled NOx-HOx−Bry chemistry above sunlit polar snow is incomplete. Rapid transport from the North Atlantic marine boundary layer occasionally caused enhanced BrO at Summit (just two such events observed during the 12 weeks of sampling over the two seasons). In general observed reactive bromine was linked to activation of bromide (Br−) in, and release of reactive bromine from, the snowpack. A coupled snow-atmosphere one-dimensional model that assumed snow photochemistry as the only source successfully simulated observed NO and BrO at Summit during a three day interval when winds were weak (transport not a factor). The source of Br− in surface and near surface snow at Summit is not entirely clear, but concentrations were observed to increase when stronger vertical mixing brought free tropospheric air to the surface. Reactive Bry mixing ratios above the snow often increased in the day or two following increases in snow concentration, but this response was not consistent. On seasonal time scales concentrations of Br− in snow and reactive bromine in the air were directly related.
Evaluation of discrepancy between measured and modeled oxidized mercury species
Authors: Kos G. , Ryzhkov A. , Dastoor A. , Narayan J. , Steffen A. , Ariya P. A. , Zhang L.
Published: July 2012

Abstract. Zhang et al. (2012a), in a recent report, compared model estimates and new observations of oxidised and particulate mercury species (Hg2+ and Hgp) in the Great Lakes region and found that the sum of Hg2+ and Hgp varied between a factor of 2 to 10 between measurements and model. They suggested too high emission inputs and too fast oxidative conversion of Hg0 to Hg2+ and Hgp, as possible causes. This study quantitatively explores in detail the uncertainties in measurements, in addition to the above concerns and speciation of mercury near emission sources in the model to better understand these discrepancies in the context of oxidized mercury, i.e. gaseous (Hg2+) and particulate (Hgp) mercury. These include sampling efficiency, composition of sample, interfering species and calibration errors for measurements and in-plume reduction processes. Sensitivity simulations using Global/Regional Atmospheric Heavy Metals Model (GRAHM) were performed to analyze the role of in-plume reduction on ambient concentrations and deposition of mercury in North America. The discrepancy between simulated and observed concentrations of Hg2+ and Hgp was found to be reduced when a ratio for Hg0:Hg2+:Hgp in the emissions was changed from 50:40:10 (as specified in the original inventories) to 90:8:2 to account for in-plume reduction of Hg0 processes. A significant reduction of the root mean square error (e.g., 19.22 to 11.3 pg m−3 for New Jersey site NJ54) and bias (67.8 to 19.3 pg m−3 for NJ54) for sampling sites in the Eastern United States and Canada, especially for sites near emission sources was found. Significant improvements in the spatial distribution of wet deposition of mercury in North America was noticed. Particularly, over-prediction of wet deposition near anthropogenic sources of mercury was reduced by 43%. On a regional scale, estimated wet deposition improved by a factor of 2 for areas with more than 12 μg m−2 yearly average wet deposition. Model sensitivity simulations show that the measured concentration of oxidized mercury is too low to be consistent with measured wet deposition fluxes in North America. This improvement by a factor of 2 and measurement uncertainties within a factor of 3 to 8 provides a reasonable rationale for the discrepancy of a factor of 2–10 determined by Zhang et al. (2012a).
Remote sensing of CO2 and CH4 using solar absorption spectrometry with a low resolution spectrometer
Authors: Petri C. , Warneke T. , Jones N. , Ridder T. , Messerschmidt J. , Weinzierl T. , Geibel M. , Notholt J.
Published: July 2012

Abstract. Throughout the last few years solar absorption Fourier Transform Spectrometry (FTS) has been further developed to measure the total columns of CO2 and CH4. The observations are performed at high spectral resolution, typically at 0.02 cm−1. The precision currently achieved is generally better than 0.25%. However, these high resolution instruments are quite large and need a dedicated room or container for installation. We performed these observations using a smaller commercial interferometer at its maximum possible resolution of 0.11 cm−1. The measurements have been performed at Bremen and have been compared to observations using our high resolution instrument also situated at the same location. The high resolution instrument has been successfully operated as part of the Total Carbon Column Observing Network (TCCON). The precision of the low resolution instrument is 0.32% for XCO2 and 0.46% for XCH4. A comparison of the measurements of both instruments yields an average deviation in the retrieved daily means of ≤0.2% for CO2. For CH4 an average bias between the instruments of 0.47% was observed. For test cases, spectra recorded by the high resolution instrument have been truncated to the resolution of 0.11 cm−1. This study gives an offset of 0.03% for CO2 and 0.26% for CH4. These results indicate that for CH4 more than 50% of the difference between the instruments results from the resolution dependent retrieval. We tentatively assign the offset to an incorrect a-priori concentration profile or the effect of interfering gases, which may not be treated correctly.
Evaluation of three new laser spectrometer techniques for in-situ carbon monoxide measurements
Authors: Zellweger C. , Steinbacher M. , Buchmann B.
Published: July 2012

Abstract. Long-term time series of the atmospheric composition are essential for environmental research and thus require compatible, multi-decadal monitoring activities. However, the current data quality objectives of the World Meteorological Organization (WMO) for carbon monoxide (CO) in the atmosphere are very challenging to meet with the measurement techniques that have been used until recently. During the past few years, new spectroscopic techniques came on the market with promising properties for trace gas analytics. The current study compares three instruments that are recently commercially available (since 2011) with the up to now best available technique (vacuum UV fluorescence) and provides a link to previous comparison studies. The instruments were investigated for their performance regarding repeatability, reproducibility, drift, temperature dependence, water vapour interference and linearity. Finally, all instruments were examined during a short measurement campaign to assess their applicability for long-term field measurements. It could be shown that the new techniques provide a considerably better performance compared to previous techniques, although some issues such as temperature influence and cross sensitivities need further attention.
Remote sensing-based estimation of gross primary production in a subalpine grassland
Authors: Rossini M. , Cogliati S. , Meroni M. , Migliavacca M. , Galvagno M. , Busetto L. , Cremonese E. , Julitta T. , Siniscalco C. , Morra di Cella U. , Colombo R.
Published: July 2012

Abstract. This study investigates the performances in a terrestrial ecosystem of gross primary production (GPP) estimation of a suite of spectral vegetation indexes (VIs) that can be computed from currently orbiting platforms. Vegetation indexes were computed from near-surface field spectroscopy measurements collected using an automatic system designed for high temporal frequency acquisition of spectral measurements in the visible near-infrared region. Spectral observations were collected for two consecutive years in Italy in a subalpine grassland equipped with an eddy covariance (EC) flux tower that provides continuous measurements of net ecosystem carbon dioxide (CO2) exchange (NEE) and the derived GPP. Different VIs were calculated based on ESA-MERIS and NASA-MODIS spectral bands and correlated with biophysical (Leaf area index, LAI; fraction of photosynthetically active radiation intercepted by green vegetation, fIPARg), biochemical (chlorophyll concentration) and ecophysiological (green light-use efficiency, LUEg) canopy variables. In this study, the normalized difference vegetation index (NDVI) was the index best correlated with LAI and fIPARg (r = 0.90 and 0.95, respectively), the MERIS terrestrial chlorophyll index (MTCI) with leaf chlorophyll content (r = 0.91) and the photochemical reflectance index (PRI551), computed as (R531-R551)/(R531+R551) with LUEg (r = 0.64). Subsequently, these VIs were used to estimate GPP using different modelling solutions based on Monteith's light-use efficiency model describing the GPP as driven by the photosynthetically active radiation absorbed by green vegetation (APARg) and by the efficiency (ε) with which plants use the absorbed radiation to fix carbon via photosynthesis. Results show that GPP can be successfully modelled with a combination of VIs and meteorological data or VIs only. Vegetation indexes designed to be more sensitive to chlorophyll content explained most of the variability in GPP in the ecosystem investigated, characterised by a strong seasonal dynamic of GPP. Accuracy in GPP estimation slightly improves when taking into account high frequency modulations of GPP driven by incident PAR or modelling LUEg with the PRI in model formulation. Similar results were obtained for both measured daily VIs and VIs obtained as 16-day composite time series and then downscaled from the compositing period to daily scale (resampled data). However, the use of resampled data rather than measured daily input data decreases the accuracy of the total GPP estimation on an annual basis.
Can whales mix the ocean?
Authors: Lavery T. J. , Roudnew B. , Seuront L. , Mitchell J. G. , Middleton J.
Published: July 2012

Abstract. Ocean mixing influences global climate and enhances primary productivity by transporting nutrient rich water into the euphotic zone. The contribution of the swimming biosphere to diapycnal mixing in the ocean has been hypothesised to occur on scales similar to that of tides or winds, however, the extent to which this contributes to nutrient transport and stimulates primary productivity has not been explored. Here, we introduce a novel method to estimate the diapycnal diffusivity that occurs as a result of a sperm whale swimming through a pycnocline. Nutrient profiles from the Hawaiian Ocean are used to further estimate the amount of nitrogen transported into the euphotic zone and the primary productivity stimulated as a result. We estimate that the 80 sperm whales that travel through an area of 104 km2 surrounding Hawaii increase diapycnal diffusivity by 10–6 m2 s−1 which results in the flux of 105 kg of nitrogen into the euphotic zone each year. This nitrogen input subsequently stimulates 6 × 105 kg of carbon per year. The nutrient input of swimming sperm whales is modest compared to dominant modes of nutrient transport such as nitrogen fixation but occurs more consistently and thus may provide the nutrients necessary to enable phytoplankton growth and survival in the absence of other seasonal and daily nutrient inputs.
Three-dimensional monitoring of soil water content in a maize field using electrical resistivity tomography
Authors: Beff L. , Günther T. , Vandoorne B. , Couvreur V. , Javaux M.
Published: July 2012

Abstract. A good understanding of the soil water content (SWC) distribution at the field scale is essential to improve the management of water, soil and crops. Recent studies proved that electrical resistivity tomography (ERT) opens interesting perspectives in the determination of the SWC distribution in 3 dimensions (3-D). We conducted this study (1) to check and validate the sensitivity of ERT for monitoring SWC distribution in a maize field during the late growing season; and (2) to investigate how maize plants and precipitations affect the dynamics of SWC distribution. We used time domain reflectometry (TDR) measurements to validate ERT-inverted SWC values. We also calculated the evolution of water mass balance to check whether ERT was capable of giving a reliable estimate of soil water stock evolution. We observe that ERT is able to give the same average SWC as TDR (R2 = 0.98). In addition, we showed that ERT give better estimates of the water stock than TDR thanks to its higher spatial resolution. The high resolution of ERT measurements also allows the discrimination of SWC heterogeneities. The SWC distribution shows that alternation of maize rows and inter-rows is the main influencing factor of the SWC distribution. The drying patterns are linked to the root profiles, with drier zones under the maize rows. During small dry periods, the SWC decrease occurs mainly in the two upper soil horizons and in the inter-row area. At the opposite, precipitations increase the SWC mostly under the maize rows and at the upper soil layer. Nevertheless, the total amount of rainfall during the growing season is not sufficient to modify the SWC patterns induced by the maize rows. During the experimental time, the SWC redistribution hardly occurred from maize rows to the inter-rows but lateral redistribution from the inter-row to the maize rows induced by potential gradient generates SWC decrease in the inter-rows area and in the deeper soil horizons.
The Potential of Temporary Immersion Bioreactors (TIBs) in Meeting Crop Production Demand in Nigeria
Authors: Lyam Paul Terwase , Musa Mutah Lalai , Jamaleddine Zainab O , Okere Ugochukwu Anthony , Odofin Wasiu Tiwalade
Published: July 2012

Micropropagation, popularly known for large-scale clonal propagation, is the first major and widely accepted practical application of plant biotechnology. The commercial utility of conventional micropropagation of important crop species is limited as a result of the large numbers needed annually to start up new farms in addition to high production costs. These result primarily from high labour cost, low multiplication rate or long duration of multiplication before plantlets are taken to the field, and poor survival rates resulting from contamination risks and during acclimatization. All of these constitute a major setback in the use of Micropropagation for scaling up of the several economic species for commercialization. Temporary Immersion Bioreactor system (TIBs) is a relatively recent micropropagation procedure that employs the use of automated gadgets to control rapid multiplication of plant cultures under adequate conditions. TIBs provide a more precise control of the adequate conditions (gaseous exchange, illumination etc.) required by plants for growth, development and survival than the conventional culture vessels. This bioreactor system incorporates a number of features specifically designed to simplify its operation and reduce production costs. The set-up consists of two vessels, one for the plantlets and the other one for the liquid culture media coupled together through a perforated rubber tubing that permits the flow of the liquid media from one vessel to the other. TIBs consist of three main phases: Multiplication, Elongation and Rooting phase. Plantlets propagated in TIBs have better performance than those propagated by conventional methods of micropropagation. This is as a result of a better handling of the in vitro atmosphere and the nutrition. TIBs provide a rapid and efficient plant propagation system for many agricultural and forestry species, utilizing liquid media to avoid intensive manual handling.  In addition to diminishing production costs regarding labour force, Temporary Immersion Bioreactors save energy, augment micropropagation productivity and efficiency.
Creating and Sustaining Local Union Capabilities The Role of the National Union
Authors: Frost Ann C.
Published: July 2012

Drawing on case study evidence from the automotive, steel, and glass making industries, this article examines the role played by the national union in shaping local unions’ abilities to develop and sustain the capabilities critical to managing on-going workplace restructuring. The author presents evidence suggesting the importance of five national union characteristics. These characteristics are the breadth of the national union’s representational coverage; the extent of its education and training focus on new workplace issues; the resources it devotes to research on the implications of new workplace practices; the presence of multiple communication channels; and its structuring of local union representation.
Les Groupes d'action en santé du coeur : évaluation d'un projet communautaire de promotion de la santé cardiovasculaire en milieu d'extrême pauvreté1
Authors: Filion Gilbert , Bilodeau Angèle , Panet-Raymond Jean , Martin Catherine , Labrie Louise
Published: July 2012

Les Groupes d'action en santé du coeur constituent un projet pilote de développement communautaire visant à promouvoir la santé cardiovasculaire en milieu de pauvreté. Deux expérimentations ont été réalisées de 1991 à 1994 dans un quartier défavorisé de Montréal. L'évaluation vise à expliquer leur mise en oeuvre par l'observation de la communauté cible et de l'intervention. L'analyse montre que la stratégie de mobilisation communautaire adoptée par les promoteurs du projet (la Direction de la santé publique de Montréal-Centre) n'a pas conduit à la création d'un véritable partenariat au regard des priorités et des objectifs. Elle révèle cependant que l'éducation populaire comme base d'intervention en petits groupes a favorisé la participation des citoyens, en plus d'offrir du soutien et de réduire l'isolement, d'améliorer l'estime de soi et de susciter le développement de projets dans un contexte sécurisant2.
Responsabilité pour autrui et dépendance dans la modernité avancée. Le cas de l'aide aux proches
Authors: Saillant Francine , Gagnon Éric
Published: July 2012

La responsabilité vécue par les personnes ayant la charge d'un proche dépendant s'inscrit dans des normes qui tendent à se redéfinir dans le contexte de la modernité avancée. À partir d'expériences relatées par des « aidants principaux » de diverses régions du Québec, l'article présente une réflexion sur la responsabilité inspirée des théories philosophiques de Ricoeur et de Levinas, ainsi que d'une théorie féministe basée sur la notion de travail de la reproduction. Ayant montré que l'aide et les soins doivent être pris non pas seulement dans leur sens instrumental, mais aussi et surtout dans leurs expressions de responsabilité morale, les auteurs les analysent en fonction des liens entre aidés et aidants (conjugal, filial, amical). Aux rôles et statuts (fixés par les représentations des liens dans leur dimension plus traditionnelle et entraînant des devoirs), la responsabilité vécue associe, au sein de l'expérience, l'affectif et l'électif. Elle n'est jamais complètement le produit d'un devoir à accomplir ou d'un choix : ses deux sens « sédimentés » ouvrent pour les sujets des perspectives inédites.
État local et mouvement des femmes à Québec : une étude de cas
Authors: Brais Nicole , Frohn Winnie
Published: July 2012

Les municipalités québécoises ne sont pas identifiées comme des actrices majeures dans le domaine de la condition féminine. Toutefois, on peut observer depuis une dizaine d'années à Québec et à Montréal l'adoption de différentes mesures destinées à favoriser la participation des femmes à la gouverne locale et la prise en compte des conditions de vie des citoyennes dans l'élaboration des politiques et programmes municipaux. L'importante restructuration municipale enclenchée depuis l'automne 2000, qui a entraîné la fusion de la ville de Québec avec les villes de sa banlieue immédiate, a d'ailleurs suscité la création d'un collectif de groupes de femmes qui s'est donné pour mission de faire émerger les enjeux « femmes ». Les auteures proposent une analyse de la dynamique du mouvement des femmes à partir d'une étude de cas portant sur Québec et sa région, afin d'expliquer l'intérêt récent des groupes de femmes pour la dimension sexuée de la politique et des institutions municipales.
Femmes élues et syndicalistes : une participation sous contraintes
Authors: Le Quentrec Yannick , Rieu Annie
Published: July 2012

Malgré des avancées sociales et politiques incontestables, la représentation numérique des femmes continue de progresser avec lenteur, surtout dans les niveaux supérieurs de responsabilité. Cette situation minoritaire, dont on ne souligne pas assez le caractère limitatif, rend les changements observés dans les pratiques et les décisions prises relativement contrastés mais néanmoins significatifs. Cette mise à l'écart des femmes est analysée à partir du point de vue de certaines organisations. Leur discours se caractérise par une ambivalence face aux questions de genre, entre une conscience relative de la domination masculine et de la nécessaire mise en oeuvre d'une mixité et la difficulté à mettre en place des fonctionnements intégrant la différence sexuée non naturalisée. Par ailleurs, la participation des femmes est également tributaire de la multiplicité des rôles sociaux qu'elles assument. Dans ce cadre, les comportements qu'elles adoptent ont un caractère subi, mais aussi stratégique.
Être musulman après le 11 septembre : l’expérience des descendants d’immigrés maghrébins en France
Authors: Santelli Emmanuelle
Published: July 2012

En retenant l’expérience des descendants d’immigrés maghrébins en France, cet article tente une synthèse des recherches de l’auteure. Si ces dernières ne portaient pas explicitement sur la question religieuse, mais plutôt sur l’insertion socioprofessionnelle et la conjugalité, elles comportaient néanmoins de nombreux éléments à même de contribuer à une réflexion sur ce que signifie « être musulman en France après le 11 septembre ». Ce questionnement sera traité, d’abord, par le biais des discriminations rencontrées dans le monde du travail, avant d’aborder la question des préjugés subis dans la vie quotidienne. Car, outre l’inégalité de traitement, il s’agit d’interroger l’effet de la stigmatisation dans la construction de la citoyenneté de ces individus. Le rôle des médias est mis en cause dans la production des représentations négatives. Renverser le stigmate constitue une lutte pour la définition de soi qui concourt à l’affirmation d’une nouvelle identité musulmane.
L’émigration marocaine au Canada : contextes de départ et diversité des parcours migratoires
Authors: Garneau Stéphanie
Published: July 2012

Les nouveaux arrivants d’origine marocaine au Québec, pourtant majoritairement diplômés et qualifiés en vertu des politiques québécoises et canadiennes d’immigration sélective, rencontrent des difficultés d’insertion professionnelle. À partir d’une double enquête ethnographique réalisée au Maroc et au Québec, cet article veut dépasser l’apparente homogénéité socioéconomique de cette catégorie nationale de migrants pour mettre au jour sa différenciation interne ainsi que la diversité de ses stratégies et parcours migratoires. Les multiples formes de parcours sont le fruit d’une dynamique entre les origines socioéconomiques des migrants, leur histoire migratoire familiale et collective, les mutations sociétales au Maroc, la fermeture des frontières européennes et les politiques d’immigration canadiennes et québécoises. En outre, la perspective théorique et méthodologique empruntée permet d’éviter les pièges de la « culturalisation » des phénomènes sociaux en nous rappelant que les parcours migratoires et les stratégies des acteurs sociaux s’inscrivent dans des territoires – pluriels – faits de rapports politiques, culturels, sociaux et économiques concrets.
Effect of the root-lesion nematode (Pratylenchus penetrans) on annual bluegrass (Poa annua)
Authors: Bélair Guy , Simard Louis
Published: July 2012

This study was undertaken to assess the effect of various population densities of the root-lesion nematode (Pratylenchus penetrans) on the growth of annual bluegrass (Poa annua) under controlled conditions. In two separate experiments, the nematodes were inoculated at concentrations of 100, 500, 1000 or 5000 nematodes 100 cm‑3 soil per pot or per tube. Nine wk post-inoculation, root P. penetrans populations had increased linearly with initial nematode concentrations in both experiments. Growth and quality of turfgrass were uniform for all treatments, with no significant difference from the control. Under the current experimental conditions, P. annua was shown to be a tolerant host plant to P. penetrans.
Historische Komparatistik und Kulturtransferforschung. Vom bilateralen Beispiel zu Beiträgen für eine globale Geschichte1
Authors: Middell Matthias
Published: July 2012

Der vorliegende Aufsatz beschäftigt sich mit der aus den 90er Jahren des vergangenen Jahrhunderts datierenden Kontroverse zwischen Vertretern einer historischen Komparatistik einerseits und Anhängern der „transferts culturels“ andererseits. Sein hauptsächliches Anliegen ist eine bessere Herausarbeitung des historischen Kontextes dieser Kontroverse als auch ihrer Auswirkungen. Zu diesem Zweck wird in einem ersten Schritt an verschiedene, seit dem Ende des 19. Jahrhunderts vorgelegte Anläufe zur Herausarbeitung der Idee einer Weltgeschichte erinnert. Daran anschließend wird hervorgehoben, dass die Intensität der genannten Kontroverse, insbesondere hinsichtlich ihrer deutschen Ausprägung, nur verständlich wird vor dem Hintergrund zweier entscheidender Aspekte: der besonderen historischen Situation am Beginn der 90er Jahre des 20. Jahrhunderts und der Diskussion um einen deutschen „Sonderweg“.
Apprendre à boire ?
Authors: Dally Sylvain
Published: July 2012

Les modalités de consommation d’alcool sont influencées par des facteurs religieux, en particulier en ce qui concerne le vin, dont la place est ambivalente dans la bible. Dans les pays de tradition catholique, le vin est la boisson des repas et il joue un rôle important en tant que facteur de cohésion des groupes et dans l’établissement des rapports entre parents et enfants. Les intervenants en alcoologie doivent prendre en compte ces données dans leur pratique.