bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling of a Thermal Discharge in an Ice-covered Estuary in Finland
Authors: de Graaff Reimer , Lindfors Antti , de Goede Erik , Rasmus Kai , Morelissen Robin
Published: March 2015

Numerical modelling of ice growth, melt and transport on regional scales such as coastal seas, estuaries, rivers or lakes can provide crucial input for safe and efficient designs and installations of marine infrastructure in arctic, sub-arctic or mid-latitude regions. The modelling of ice and related complex physical processes on these regional scales is however still rather unexplored.

The complexity of ice modelling on local and regional scales is best illustrated in areas where ice-covered sea water is mixed with fresh river water and a thermal discharge from for instance a refinery or power plant. Such a situation exists in the Svartbackfjarden, an estuary some 35 km to the east of Helsinki, Finland. Two minor rivers discharge into this estuary. The estuary freezes during the winter with ice thicknesses typically in the range of 20 to 50 cm. In this estuary an oil refinery takes in cooling water at a depth of about 15 m. The heated water is discharged at the surface and results in melting of the sea ice in the vicinity of the outfall. However, given the fresh water from the rivers in the early spring, and the fact that the salinity of the intake water is higher than the surface water, the discharged cooling water has been observed to flow under the relatively cold fresh layer just under the ice. Due to mixing of the plume with the surrounding water, the temperature of the fresh water layer increases, leading to melting of the ice at some distance from the plant's outfall.

This paper presents a case study with Delft3D, which is a flexible integrated numerical modelling programme that enables simulation of 3-dimensional flow, sediment transport, morphology, waves, spills, water quality and ecology, in combination with a recently developed ice module. The 3-dimensional modelling with Delft3D of the thermal discharge from the oil refinery in the ice-covered Svartbackfjarden estuary is presented and compared to local observations of currents, water temperature, salinity and ice thickness. The case study will show the capability of Delft3D to cover all the relevant physical processes that determine the temporal and spatial characteristics of the ice and the thermal discharge, under influence of fresh river discharges, hydrodynamic, meteorological and atmospheric forcing.

These capabilities will contribute to the further development of integrated ice modelling on regional scales, eventually benefiting the sustainability, efficiency and safety of the designs of marine structures in ice-covered waters.
Virtual Arctic Simulation Environment
Authors: Hamilton Matthew , Dodd Stephen
Published: March 2015

We present a virtual software simulation system for remotely-operated vehicle (ROV) operations in arctic and harsh environments particularly focused on subsea trenching. The system provides interactive, three-dimensional graphics and dynamics simulation with high fidelity. In addition to standard ROVs, the system can now simulate trenching and dredging vehicles such as jetters and ploughs. It also provides support for integration of data for visualization and analysis from a wide range of sources including sub-bottom imaging, seismic, bathymetry and sidescan sonar. Visualizations can be controlled to enhance features important for geological and geotechnical analysis.
Post-simulations of Ice Basin Tests of a Moored Structure in Broken Ice - Challenges and Solutions
Authors: Bonnemaire Basile , Tan Xiang , Serré Nicolas , Fredriksen Arnt , Metrikin Ivan , Gürtner Arne
Published: March 2015

Interaction between a moored structure and drifting broken ice is a complex process. To document the expected structure response, ice basin tests of the interaction are common practice. The outcomes of ice basin tests need to be carefully analyzed before extrapolation to expected full-scale target responses. The preferred strategy is to use numerical simulations to correct the measurements. The numerical model needs to be qualified by successful post-simulations of the achieved ice basin interactions.

Post-simulations of interactions between drifting broken ice and a moored floating structure are of high complexity. The response of both the structure and the ice field needs to be replicated. This requires a good modeling of the ice field properties that matter (such as the floe size distributions and concentrations) and the boundary conditions affecting the interactions (such as the effect of the ice basin walls).

Statoil's SIBIS numerical model is used to post-simulate ice basin tests of the moored Cat-I drillship. The present paper discusses the challenges with such post-simulations and presents the philosophy chosen for achieving successful postsimulations.
Autonomous Underwater Vehicle Operations in the Arctic
Authors: McMillan John
Published: March 2015

There is an increasing interest in Arctic and Antarctic studies, both from a scientific and commercial point of view. Due to the unpredictable climate conditions and the ice cover, as well as the difficulty conducting AUV operations with support ships with the cost and scarcity of icebreakers and the presence of thick ice, AUVs are an ever-increasing option due to their ability to survey underneath the ice at long intervals.

Users are becoming more receptive to the idea of using AUVs in unsupervised under-ice operations, and the capability to do this is advancing. International Submarine Engineering Ltd is the only subsea AUV developer with the Arctic experience behind it, specifically in operational hours under the ice.

There is no doubt that the basis for ISE's successes lies in using a reliable, robust AUV and the underlying twenty years of work contributed to its development. For ISE, research deployments in the 1980's and 1990's and subsequent AUV deployments also provided background experience that was invaluable. From there, pulling off a successful under-ice deployment was essentially a matter of planning and testing.

An example of the capability of current AUVs to operate unsupervised is the high Arctic field work by two Arctic Explorer Autonomous Underwater Vehicles (AUVs) built by ISE for Natural Resources Canada (NRCan). They were deployed in 2010 and 2011 to conduct under-ice bathymetric surveys in support of Canada's sovereignty claim under the United Nations Convention on the Law of the Sea (UNCLOS). These were the first long range AUV missions to have been undertaken at high latitude, and the first in which seabed survey data was successfully gathered over long distances working from both ice camps and icebreakers.

As Autonomous Underwater Vehicles (AUVs) are now exploring more challenging terrain than ever, the need for an obstacle avoidance system has become apparent. Obstacle avoidance systems (OAS) in unmanned systems are far from new. However, adapting existing methodologies to AUVs presents a new set of challenges.

Last year, International Submarine Engineering Ltd (ISE) tackled the task of adding an OAS to its line of Explorer AUVs. ISE's experience with obstacle avoidance strategies started in 1985 when the technology was added to ARCS, ISE's first AUV. ISE is the only company in the world with proven under the ice capability using AUVs.

This presentation will cover the experiences ISE has under its belt with Arctic operations as well as how new technologies have been applied in order to tackle the ever growing need to perform successful operations under the ice.
Using Autonomous Marine Vehicles to Enable Accurate Wellbore Placement in the Arctic
Authors: Poedjono Benny , Pai Sudhir , Maus Stefan , Manoj Chandrashekaran , Paynter Ryan
Published: March 2015

This paper describes a study using an autonomous marine vehicle with satellite communications, to accurately collect and deliver in real-time magnetic measurements, to calculate Total Magnetic Intensity in marine environments in the absence of Earth magnetic observatories.

New capabilities in the monitoring of auroral electrojet disturbances allow improved well placement for increased oil and gas recovery in the Arctic, and provide operators accurate geomagnetic reference values, enabling tighter quality control of MWD equipment, enhancing safety and reducing nonproductive time.

In the Arctic, Measurement while drilling (MWD) processing must include corrections for rapid changes in the geomagnetic field caused by auroral electrojet currents. The auroral zone is a region where the electric field of the magnetosphere precipitates along magnetic field lines into the ionosphere. Converting the magnetic azimuth to a true azimuth requires accurate knowledge of the geomagnetic field at the point of measurement downhole at the drill bit. Equipped with this information lateral uncertainties can be reduced by 50%.

At higher latitudes, the strength of the horizontal component of the geomagnetic field shrinks, which exacerbates any error sources that accumulate while surveying. This has an enormously negative effect on surveying accuracy at high latitudes. Data from Earth magnetic observatories and variometer stations can be analyzed to characterize the auroral electrojets and compensate for the disturbance. Knowledge of the spatial structure of the electrojets’ magnetic signature is essential for deploying a ground network of monitoring stations in the Arctic. This network provides the real-time geomagnetic infrastructure essential to support MWD operations, making it the most cost-effective technology available to achieve accurate wellbore placement in horizontal, relief well, and extended reach drilling. However the number of Earth magnetic observatories is limited in the Arctic.

Autonomous marine vehicles can now be deployed for geomagnetic surveying. In recent testing, two autonomous marine vehicles were equipped with towed magnetometers. To investigate the accuracy of the measurements, the two vehicles surveyed exact-repeat profiles. The measurements of the two vehicles agreed to within 2nT, exceeding even the stringent 5nT standard for geomagnetic observatories. This test demonstrates the utility of autonomous marine vehicles to carry out crustal magnetic surveys and monitor disturbance fields in support of offshore directional drilling operations.

Note: This paper is a consolidation of 2 papers, Poedjono et al, OTC-25228 and OTC 1726418
Iceberg Remote Sensing in Arctic Harsh Conditions
Authors: Kim Anna N. , Scibilia Francesco , Bouquet Grégory
Published: March 2015

Ice remote sensing is a critical element of ice management for oil and gas operations in Arctic waters. Both strategic and tactical decisions related to drilling and production operations are significantly influenced by the ice detection capabilities. Common ship borne remote sensing systems today include marine radars, optical and thermal infrared sensors.

However, a range of adverse environmental factors can dramatically reduce the performance of these systems. Fog, haze, strong wind, snow and rain, waves, along with the Arctic winter nights can create challenging operating conditions. Particularly the detection of relatively small icebergs (namely growlers and bergy bits) in harsh weather conditions often arises as a hazard for marine operations.

Remote sensing technology is developing continuously. Several techniques aimed at enhancing sensor performance under poor visibility or in darkness do exist today. Active illumination for example, can be used to compensate for lacking of sufficient external light.

This paper presents a review of the current and emerging remote sensing technologies that can be applied for growlers and bergy bits detection under harsh Arctic weather conditions. The frequency range of the ice sensors studied covers parts of the electro-magnetic (EM) spectrum, which include visible light (0.38 to 0.7 µm) and infrared (IR) (0.75 µm to 15µm). Sensing technologies such as LiDAR (Light Detection And Ranging), hyperspectral imaging, and thermal IR image are evaluated. Promising enhancing techniques as active illumination and range-gate imaging are discussed.
The Distribution of Massive Ice Features by Ice Types from Multi-Year Upward Looking Sonar Ice Draft Measurements
Authors: Fissel David B. , Ross Ed , Sadowy Dawn , Wyatt Glenda J.
Published: March 2015

Modem ULS instruments provide year-long continuous measurements of sea ice drafts with an unprecedented time resolution of 1-2 seconds and a horizontal resolution of approximately 1 m. In this paper we analyze multi-year moored ULS measurements of sea ice in the Chukchi and Beaufort Seas and off Northeast Greenland. Recently, the massive ice feature (MIF) parameter has been developed to provide a robust, geometrical characterization of all potentially hazardous marine ice features within a ULS ice draft data set. An MIF episode is the set of consecutive ice draft values which exceed a specific minimum ice draft (e.g. 1.2 or 2.0 m) having total cross-sectional area above a specified value (e.g. 250 m2). A database of all MIF episodes is prepared including area, distance and ice drafts (mean and maximum).

Previous research has shown the MIF database from year-long mooring measurements to be a complete and robust characterization of potentially hazardous features. In this paper, we apply algorithms that detect different types of sea ice features: large singular ice keels, hummocky ice, thick brash ice, old or multi-year ice and marine glacial ice (icebergs and ice islands). These ice types are associated with individual MIF episodes so that each episode can be associated with one or more ice type. There are large variations in the numbers of MIF episodes among regions, with NE Greenland having the most frequent occurrences of MIFs. For NE Greenland approximately 40% of MIF episodes can be identified as large keels and less than 15% as hummocky ice episodes; however, the hummocky ice episodes typically have considerably larger crosssectional areas than large keels. There are fewer occurrences of multi-year ice and very rare occurrences of marine glacial ice. The MIF analysis results provide improved quantitative values for pressure loading of sea ice on offshore platforms and ships, as well as understandings about the nature of sea ice deformation and age characteristics.
Arctic Development of the Canadian Beaufort Sea, Geohazards and Export Route Options
Authors: Nash Ian
Published: March 2015

Studies have suggested that the Arctic contains over 30% of the world's untapped natural gas reserves, and approximately 13% of its undiscovered oil reserves. The Beaufort shelf in the Canadian Arctic has been of interest for Oil and Gas development for many decades and reached a peak in the Mid 1980's when over 50 drilling islands were built to explore potential reserves by various international oil companies, with 92 wells recorded in the Canadian Beaufort Sea area.

The Amauligak field was discovered in the Canadian Beaufort in 1984, and is still the largest oil and gas discovery in the Mackenzie Delta or Beaufort Sea areas. Amauligak lies approximately 75 kilometres northwest of Tuktoyaktuk in 30 metres water depth in the Beaufort Sea. The field is thought to contain 235 million barrels of oil and 1.3 trillion cubic feet of natural gas.

Whilst vast resources such as Amauligak are known to exist in the Canadian Beaufort, the key to development of these remote areas is finding a viable export route for oil and natural gas. This was clearly the case for the development of the Prudhoe Bay Area of the Alaskan Arctic with the development of the Trans Alaskan Pipeline in the 1970's following the discovery of oil on Alaska's North Slope in 1968. This facilitated the development of the North Slope and shallow water offshore fields such as North Star which peaked in 1988 at about 738 million barrels per annum, about 25% of total U.S. production.

Unlike the offshore shallow water Prudhoe Bay Developments, the development of the Beaufort shelf and slope will bring with it significant remoteness and geohazard issues as well as the familiar ice challenges. This paper highlights some of the geohazard issues facing Canadian Beaufort developments and considers what options exist for the safe and economical export of the product to market.
Numerical Research on Usage of Podded Propulsors in Ice Management
Authors: Islam Mohammed , Jahra Fatima , Molyneux David , Hedd Lee
Published: March 2015

Although podded propulsor technology has existed for nearly two decades, there has been little research into the use of these propulsors for ice management. Full-scale ice management trials with azimuthing thrusters revealed that it was possible to break and clear ice with the propulsors' wake and that precise ice management could be achieved with the wake of this propulsion system. This means dynamic placement ofpropeller wake wash can facilitate ice breaking and ice management operations. This paper presents preliminary outcome of a research program to evaluate the potentials ofpodded propulsors as an ice management device.

The kinematics i.e. the turbulence and velocity distribution in the propeller wake wash determines the capacity of the propulsor to break, push and clear the ice. In this research, efforts are made to model the propeller wash and data were predicted to quantify the capacity of a podded propulsor to clear ice under a range of operating conditions. A Reynolds-Averaged Navier-Stokes solver is used to predict the propulsive performance of a generic podded propulsor system in various operating conditions and configurations. The effects ofpropeller shaft speed and pod configuration are evaluated. The predicted propeller thrust and torque as well as the loads on the pod are compared with corresponding data acquired in a complimentary experimental program. The simulations and measurements are carried out for both puller and pusher configurations at or near bollard pull condition and in uniform inflow condition. Analysis demonstrates that the RANS solver can accurately predict the performance coefficients of the podded propulsor in straight-ahead condition in both puller and pusher configurations. The kinematics of the propeller wash at multiple downstream locations are studied only to reveal that the pusher propulsor may be more effective in clearing ice than the puller one because of less interaction between the propeller and the strut. The current work aims to provide insight into the effect of propeller shaft speed and pod configurations on the quality of the propeller wake that can be used for ice management.
Unmanned Aircraft Systems for Geotechnical Monitoring of Pipelines in the Arctic
Authors: Cunningham Keith , Hatfield Michael , Pericón Laura Samsó
Published: March 2015

Pipelines in the Arctic must contend with a variety of geotechnical obstacles affecting their construction and long-term operation. For example, thawing permafrost leads to unstable terrain, especially on slopes and pipeline river crossings. Research funded by the US Department of Transportation is underway to investigate how unmanned aircraft systems (UAS) could be used to monitor permafrost and unstable soils in order to develop a proactive decision-support system for pipeline operators. Leading this research is the University of Alaska Fairbanks (UAF) in cooperation with the Alyeska Pipeline Service Company. The research will evaluate a variety of unmanned aircraft systems (UAS) to determine an optimal technology mix, and best practices for the persistent surveillance of thawing permafrost and shifting soils, thereby providing pipeline operators a broader picture of, and a means of mitigating, the geotechnical hazards that affect pipelines.
Remote-Controlled Cement-Pump Unit: A Step Change in Pressure Pumping
Authors: Gupta Nadish , Ray John Allen
Published: March 2015

The oil and gas industry involves various high-risk operations. In conventional oil and gas operations, pressure pumping is performed during the complete life cycle of the well. Normally, a cement-pump unit (CPU) is used to perform services such as cementing, blowout preventer (BOP) testing, formation integrity tests, and more. Operating a conventional cement unit requires the cement-unit operator to be directly over pumps and treating lines that contain pressurized fluid. During pumping operations, especially BOP testing, the pressures can get as high as 15,000 psi. Any leak or rupture in the lines at this pressure presents hazardous situation in the cement room.

As per the hazard-analysis risk-control (HARC) analysis, two factors are required to have an incident. One is "likelihood" and the other is "severity" of that risk. At present, the majority of the current industry preventive measures aim at reducing the likelihood of a risk. The remote-controlled cement-pump unit (RCCPU) sets a new benchmark in safety standards by removing the likelihood factor, thus eliminating the risks pertaining to pressure pumping. With this engineered innovation, the pump unit is in a safe room, and the cementer is in a separate control room with advanced computer systems to operate the unit. This unit isolates the cementer from risks such as pressure, noise, height, adverse climate, and more. The automated control of the unit and the cement mixing system helps in achieving a high service quality (SQ). The innovative systems and the advanced engineering that the RCCPU uses to isolate the risks from the personnel change the paradigms of pressure pumping. While the current technology still requires the RCCPU operator to be onboard the vessel, however, work is in progress to operate the RCCPU from onshore facility.
Update on a New Ice Simulation Tool using a Multi-Model Program
Authors: Septseault Cyril , Béal Pierre-Antoine , Yaouanq Sébastien Le , Dudal Alexey , Roberts Brian
Published: March 2015

In June 2012, Technip signed an agreement with Cervval (a specialist software company in Brittany) and Bureau Veritas (BV) to develop an ice-modelling simulation program. The long term aim was for the simulator to predict the flow of ice around both fixed and floating structures and calculate the ice-loadings on the platforms. The program would allow platform structures to be optimised, to minimise ice loadings and ice rubble build-up, prior to final design verification in an ice test basin.

Initially the program was developed to predict ice behaviour in shallow waters since there are several projects imminent in the North Caspian but would be equally applicable in Arctic regions. Cervval has developed the software with ice expertise input and verification from BV. The program is unique in the Artic industry in that it uses a multi-model simulator which is able to cope with the complexity of calculating the kinematic and failure behaviour for the ice sheet and for each newly created ice fragment that results from contact with the structure or due to collision with other ice rubble particles for ice mechanical properties.

At ATC 2014 , the program was first presented to the industry but was still under development. At that stage, the program was able to simulate the flow of an ice sheet as it encroached on a conical structure and to predict vertical and horizontal loads on the structure with good accuracy. It also predicted the geometry of the ice accumulation in front of the structure above and below the ice sheet.

Since ATC 2014, the software development has considered ice interaction with straight sloping wall structures, then vertical walled structures (such as artificial islands) and finally a range of floating structures.

This follow-up paper will present details of the completed simulator, the verification program and plans for the future. A typical set of ice simulations will be shown and a comparison with ice basin test results will be presented as a measure of the program's accuracy.
A Simple Model for Glory Hole Dredge Spoil Dispersion Assessment
Authors: Haneberg William C. , Bruce Brittany , Kelly Joshua T. , Davis Laurence
Published: March 2015

This paper describes a simple mathematical model of hopper dumped dredge spoil dispersion that is based upon a modified version of Stokes’ law to estimate vertical particle velocities, and empirical metocean data to estimate horizontal particle velocities. The horizontal and vertical components are combined to simulate particle paths for computational packets of different grain size fractions under metocean conditions representative of those during the discharge period. Stokes’ law is modified using published relationships to account for large and non-spherical particles. Horizontal particle transport distance is controlled by water depth, particle size, current speed, and current direction variability based upon empirical metocean current speed and direction time series. The resultant dredge spoil depositional pattern is an irregular bull's eye in which particle size and deposit thickness decrease radially from the deposit center. Transport distances for each grain size fraction generally follow a lognormal-like distribution, with distances being inversely proportional to grain size. If there is a predominant current direction during disposal, the resulting deposit will be elongated in that direction. Application of the method, variations of which have been used to support dredge spoil discharge permit applications on several unnamed projects, is illustrated for a hypothetical site.
The Remote Coast: Baseline Mapping in Preparation for Arctic Coastal Disasters
Authors: Mitchell Todd
Published: March 2015

Our coasts are a critical intersection of ecological, social, and economic interests. They are the breeding ground for aquatic plants and animals, the playground for residents and tourists, and the launching ground for shipping, fishing, and resource development projects. In arctic regions, these areas are generally poorly characterized (often due to their sheer size, sparse population and inaccessibility), yet are perhaps the most fragile environment. As such, the arctic coast is particularly vulnerable to the impacts of human activity - particularly accidental chemical spills. Reducing the risk of and/or responding to emergency situations requires a thorough understanding of both the coastal environment, adjacent submerged lands and often the jurisdictional boundaries of stakeholders. In most cases, this effort begins with a mapping program that identifies the land/seabed boundaries and usage, and provides adequate charting for over-water emergency response activities. These observations must be regularly repeated to track ongoing coastal and ecological processes as well as the impacts from episodic events. Whereas small, local site investigations are typically best performed from vessel-mounted sensors, aerial remote sensing techniques are often well suited for regional-scale mapping programs.
An Unusual Pituitary Mass Revealing a Primary Hypothyroidism!
Authors: Moumen Amal , Meftah Azzelarab , El jadi Hamza , Elmoussaoui Souad , Belmejdoub Ghizlaine
Published: March 2015

Autoimmune hypothyroidism is a common medical condition. Its revelation by thyrotrophic hyperplasia is an unusual and may be misdiagnosed as a pituitary adenoma. A 35-year-old man is referred to us for endocrinological assessment before surgery of a pituitary macroadenoma with bitemporal hemianopsia. Biological data reveal profound primary hypothyroidism. With thyroid hormone substitution, the thyroid function was normalized. Follow-up magnetic resonance imaging, showed the complete shrinkage of the pituitary mass attesting of a thyrotrophic pituitary hyperplasia. This case highlights the importance of a multidisciplinary assessment of pituitary masses to avoid unnecessary surgery and to prevent consequences of sellar masses.
Synthetic seismograms from borehole seismic data and well logs, Beaufort-Mackenzie Basin
Authors: Hu K , Brent T A , Issler D R , Chen Z
Published: March 2015

Borehole seismic survey data are compiled for 202 wells in the Beaufort-Mackenzie Basin, including vertical seismic profile, check shot and crystal cable surveys. On the basis of the well seismic data, well logs and deviation survey data (for deviated wells),
synthetic seismograms are generated for the 202 wells using Well Editor (GeoGraphix, R2007.2). The resulting synthetics are illustrated with a time/depth window, well logs, well seismic data, calculated velocity, as well as stratigraphic information and casing shoe depths. The presentation of
results provides key time-depth relationships important to seismic interpretation, but it also shows log responses in the time domain to rationalize reflection events by effectively tying well tops and other levels to surface-seismic reflection profiles. The information is also useful for the
identification of permafrost (Hu et al., 2013) and gas hydrate zones as well as for other types of sedimentary basin studies.
Expression of Polarity Genes in Human Cancer
Authors: Lin Wan-Hsin , Asmann Yan W. , Anastasiadis Panos Z.
Published: March 2015

Polarity protein complexes are crucial for epithelial apical-basal polarity and directed cell migration. Since alterations of these processes are common in cancer, polarity proteins have been proposed to function as tumor suppressors or oncogenic promoters. Here, we review the current understanding of polarity protein functions in epithelial homeostasis, as well as tumor formation and progression. As most previous studies focused on the function of single polarity proteins in simplified model systems, we used a genomics approach to systematically examine and identify the expression profiles of polarity genes in human cancer. The expression profiles of polarity genes were distinct in different human tissues and classified cancer types. Additionally, polarity expression profiles correlated with disease progression and aggressiveness, as well as with identified cancer types, where specific polarity genes were commonly altered. In the case of Scribble, gene expression analysis indicated its common amplification and upregulation in human cancer, suggesting a tumor promoting function.
Black-carbon-surface oxidation and organic composition of beech-wood soot aerosols
Authors: Corbin J. C. , Lohmann U. , Sierau B. , Keller A. , Burtscher H. , Mensah A. A.
Published: March 2015

Abstract. Soot particles are the most strongly light-absorbing particles commonly found in the atmosphere. They are major contributors to the radiative budget of the Earth and to the toxicity of atmospheric pollution. Atmospheric aging of soot may change its health- and climate-relevant properties by oxidizing the primary black carbon (BC) or organic particulate matter (OM) which, together with ash, comprise soot. This atmospheric aging, which entails the condensation of secondary particulate matter as well as the oxidation of the primary OM and BC emissions, is currently poorly understood. In this study, atmospheric aging of wood-stove soot aerosols was simulated in a continuous-flow reactor. The composition of fresh and aged soot particles was measured in real time by a dual-vaporizer aerosol-particle mass spectrometer (SP-AMS). The SP-AMS provided information on the OM, BC, and surface composition of the soot. The OM appeared to be generated largely by cellulose and/or hemicellulose pyrolysis, and was only present in large amounts when new wood was added to the stove. BC signals otherwise dominated the mass spectrum. These signals consisted of ions related to refractory BC (rBC, C+1−5), oxygenated surface groups (CO+1−2), potassium (K+) and water (H+2O and related fragments). The C+4 : C+3 ratio, but not the C+1 : C+3 ratio, was consistent with the BC-structure trends of Corbin et al. (2015c). The CO+1−2 signals likely originated from BC surface groups: upon aging, both CO+ and CO+2 increased relative to C+1−3 while CO+2 simultaneously increased relative to CO+. Factor analysis (PMF) of SP-AMS and AMS data, using a new error model to account for peak-integration uncertainties, indicated that the surface composition of the BC was approximately constant across all stages of combustion for both fresh and aged samples. These results represent the first time-resolved measurements of in-situ BC-surface aging and suggest that the surface of beech-wood BC may be modelled as a single chemical species.
Gully geometry: what are we measuring?
Authors: Casalí J. , Giménez R. , Campo-Bescós M. A.
Published: March 2015

Abstract. Many of the researches on (ephemeral) gully erosion comprise the determination of the geometry of these eroded channels specially width and depth. This is not a simple task due to uncertainty generated by the wide range of variability of gully cross-section shape found in the field. However in the literature this uncertainty is not recognized and then no criteria in the measurement procedure is indicated. The aim of this work is to make the researchers aware of the ambiguity that arises when characterizing the geometry of an ephemeral gully and similar eroded channels. Besides, a measurement protocol is proposed with the ultimate goal of pooling criteria in future works. It is suggested to characterize the geometry of a gully through its effective width and effective depth, which, together with its length, define an "equivalent prismatic gully" (EPG). The latter would facilitate the comparison between each other of different gullies.
Arquitetura da informação em livros: uma aproximação a partir do comportamento de busca dos usuários
Authors: Nascimento Neto Gustavo Henrique do , Nascimento Geysa Flávia Câmara de Lima
Published: April 2015

O livro é mais do que suporte de dados. É um ambiente de excesso de informação, uma vez que está repleto de signos. Ao longo do tempo, foram desenvolvidos vários instrumentos e formas de usar com mais proveito este tipo de documento. Pode-se assim afirmar que existe uma arquitetura da informação voltada para o livro impresso. Este artigo descreve os instrumentos de arquitetura da informação usados nos livros, sob a ótica da navegação em ambientes informacionais. Capa, descrição, ficha catalográfica, paginação são alguns dos artifícios utilizados para a orientação do leitor no livro. Divide os instrumentos da arquitetura da informação do livro em navegação interna pré-textual: sumário e listas; navegação interna textual: páginas capitulares, capítulos, seções, subseções, título corrente, notas; navegação interna pós-textual: índices; e navegação externa: citações e referências. Conclui que esses instrumentos foram desenvolvidos a partir do uso do livro.
Blending Artistic, Research and Teaching Practices in the Context of Teacher Education. An a/r/tographical Approach of an Arts-Based Educational Project
Authors: Kampouropoulou Maria
Published: March 2015

The purpose of this article is to explore an art education project within the theoretical and methodological context of a/r/tography. An arts-based educational project carried out by the Primary Education Department of University of Aegean, is examined through an artistic and inquiry process where the roles of artists, researchers and teachers are deeply interrelated. In order to explore how artful research and the co-creative process can help teachers access and reframe understandings of teaching and learning, the teacher trainees were interviewed and expressed ideas and beliefs on education, art, inquiry, teaching and knowledge construction. Findings of the research support the potential of art-based educational projects to evoke strong senses of artist/researcher/teacher self in relation to the community, empower cognitive, communicative and artistic skills, promote holistic learning and thus to play a significant role in the field of teacher education.
Zen and Zarathustra: Self-Overcoming without a Self
Authors: van der Braak André
Published: April 2015

A confrontation with the Zen Buddhist tradition can help to open up new perspectives on Nietzsche's thought that take us beyond the “familiar” Nietzsche. There are some gaps in most Nietzsche interpretations that could be fruitfully addressed by means of a comparison with East Asian thought. This article argues that Nietzsche's philosophy and Zen philosophy can both be considered philosophies of self-overcoming in four different respects: theoretical, performative, self-referential, and expressive. In a theoretical sense, both stress the importance of self-overcoming. In a performative sense, both aim at self-overcoming in the reader. In a self-referential sense, they continually overcome themselves as philosophy. In a self-expressive sense, both can be viewed as a celebration and expression of self-overcoming; they are philosophies of laughter and play. In reading Nietzsche's Thus Spoke Zarathustra, these four aspects meet each other.
Omnidesire as the Ending of Desire: Zarathustra, Mahāyāna Buddhism, Tiantai
Authors: Ziporyn Brook
Published: April 2015

Nietzsche's Thus Spoke Zarathustra is a work that bears comparison to Mahāyāna Buddhist literature in more ways than one. Nietzsche was turning against the Schopenhauerian doctrine of the denial of the will, which he read as symptomatic of a larger nihilistic trend swallowing up almost all existing spiritual culture, while the Mahāyāna was turning against the world-denying implications of the doctrine of Nirvana as the ending of desire and samsara that was so central to early Buddhism. In this article, I explore one move made in both of these cases: the move from total negation to total affirmation seen as a convergence of these two apparently opposed extremes. Of central interest here is the “identity of indiscernibles” that applies structurally to these two opposite extremes, “willing nothing” and “willing everything,” with the latter effected only through “willing one thing intensely,” at once excluding and including all other things, and its liberative potential.
Naturalism, Causality, and Nietzsche's Conception of Science
Authors: Remhof Justin
Published: April 2015

There is a disagreement over how to understand Nietzsche's view of science. According to what I call the Negative View, Nietzsche thinks science should be reconceived or superseded by another discourse, such as art, because it is nihilistic. By contrast, what I call the Positive View holds that Nietzsche does not think science is nihilistic, so he denies that it should be reinterpreted or overcome. Interestingly, defenders of each position can appeal to Nietzsche's understanding of naturalism to support their interpretation. I argue that Nietzsche embraces a social constructivist conception of causality that renders his naturalism incompatible with the views of naturalism attributed to him by the two dominant readings.
Renal Dysplasia
Authors: Chen Rui-Yun , Chang Han
Published: March 2015

Renal dysplasia is an aberrant developmental disease usually diagnosed during the perinatal and childhood years. Prevalence is estimated at 0.1% of infants (via ultrasound screening) and 4% of fetuses and infants (via autopsy study). Occurrences may be combined with abnormalities in the collecting system or associated with complex syndromes. Histopathology shows primitive tubules surrounded by a fibromuscular collar. The differential diagnosis includes renal dysplasia, hypoplasia, and renal atrophy. Immunohistochemical expression of the paired box genes 2 and 8 (PAX2/8) and Wilms tumor 1 (WT1) is increased in the primitive ducts and fibromuscular collar, respectively. Renal dysplasia pathogenesis is not well understood, but may be caused by a nephron-inductive deficit due to ampullary inactivity or abnormal budding of the ureteric bud from the mesonephric duct. Either the PAX2 mutation only or cross-talk with the p53 pathway is involved in this deficit. Nephrectomy is the treatment of choice for symptomatic renal dysplasia.
Un dialogue de sourds ?
Authors: Charbonneau François
Published: March 2015

Cet article s’intéresse aux attitudes par rapport au bilinguisme dans l’espace public anglo-canadien. À l’aide de citations tirées à même une banque de près de 800 articles de journaux publiés entre 2004 et 2009, est détaillé l’ensemble des arguments invoqués dans ce débat. La recherche démontre que lorsqu’ils critiquent le bilinguisme, les détracteurs de cette politique mobilisent des arguments presque exclusivement de nature pragmatique. En lisant cette fois les textes écrits par des gens se portant à la défense des politiques de bilinguisme, les arguments invoqués sont très souvent de nature « idéaliste ». En un mot, les « participants » à ce débat prennent part à un dialogue de sourds. Cette recherche permet de comprendre pourquoi plusieurs des arguments invoqués en appui aux politiques de bilinguisme du Canada restent, pour une partie de la population du Canada, largement inaudibles.
Légitimité et devenir en situation linguistique minoritaire
Authors: Landry Rodrigue
Published: March 2015

Le texte propose un cadre théorique qui permet d’analyser l’effet de la légitimité sur le devenir d’une minorité. Selon ce modèle, la légitimité externe n’est pas toujours garante d’une forte légitimité interne. Le cadre théorique permet d’analyser des rapports de force qui influent sur la légitimité des minorités linguistiques non seulement par des pressions externes observables, mais aussi par la pénétration dans l’imaginaire intime de chaque individu. L’ article présente des résultats sur le métissage identitaire, phénomène déjà bien évident et observable chez une majorité des membres des communautés francophones et acadiennes. Les francophones semblent être influencés par deux discours légitimant en opposition, c’est-à-dire par l’idéologie dominante qui accorde la préséance à la légitimité culturelle de la langue anglaise, et concomitamment par des expériences de solidarité avec le groupe francophone qui renforcent un discours de légitimité de solidarité favorable à la francophonie.
Accueillir le majoritaire dans l’institution de la minorité ?
Authors: Cormier Marianne
Published: March 2015

Une minorité peut chercher à manifester sa légitimité en s’affirmant et en luttant pour sa reconnaissance. C’est ainsi que la minorité francophone a livré bataille pour des écoles de langue française. Or, face à des défis démographiques, ces écoles deviennent de plus en plus hétérogènes. Cette étude examine les perceptions d’acteurs scolaires et de parents exogames ayant un enfant en maternelle. Des entretiens avec ces personnes dans neuf écoles du Nouveau-Brunswick ont permis une analyse thématique qui révèle que les acteurs scolaires veulent accueillir ces familles, mais avec certaines réserves. Les parents se sentent, en général, accueillis, malgré une barrière langagière qui limite leur participation. L’ ambigüité est présente et les tensions entre légitimité et inclusion se manifestent au sein de l’école.
Légitimité interne des politiques linguistiques au Québec : le regard des immigrants récents
Authors: Calinon Anne Sophie
Published: March 2015

Cet article aborde la question de la légitimité des actions de politiques linguistiques menées par le Québec en matière d’intégration linguistique au français selon le point de vue des allophones récemment arrivés dans la province. Nous nous demandons comment les immigrants récents au Québec, installés à Montréal, perçoivent les enjeux autour de leur francisation et quelles sont leurs représentations de leur place actuelle et projetée dans la société québécoise francophone. Une analyse des politiques et une ethnographie montrent que les immigrants récents ont du mal à se considérer comme membres à part entière de la société francophone, compte tenu de leur compétence linguistique en construction, de leur vision encore très monolingue et monolithique de la communauté francophone et d’un manque de passé en commun. Les faibles échanges avec des francophones considérés comme « légitimes » – les natifs – ont un impact direct sur leur sentiment d’appartenance et leur intégration sociale.
La Francophonie canadienne, un ensemble légitime en changement
Authors: Allaire Gratien
Published: March 2015

La Francophonie canadienne est bien en vie. Elle trouve son origine dans le Canada français et elle est le résultat des grands changements que celui-ci a connus au cours du dernier demi-siècle. Le Canada français était tout aussi unitaire que le Canada anglo-britannique. La Francophonie canadienne se distingue par la complexité de sa francité, par sa modernité, par son urbanité. Elle est tout en nuances, inclusive, un ensemble de communautés provinciales, régionales, locales qui se savent légitimes et dont on reconnaît la légitimité, tant sur les plans historico-géographique et sociopolitique que sur les plans constitutionnel et juridique. Elle a changé au cours des décennies et elle continue, et continuera, de se transformer, perméable aux courants culturels. Elle est devenue un ensemble dont le coeur est constitué par les francophones « de souche », entouré de francophones de langue officielle, d’anglophones d’origine culturelle française et de sympathie française. C’est ce qui fait sa grande richesse.
Dynamics governing the response of tidal current along the mouth of Jiaozhou Bay to land reclamation
Authors: Lin Lei , Liu Zhe , Xie Lian , Gao Huiwang , Cai Zhongya , Chen Ziyu , Zhao Jianzhong
Published: April 2015

Data collected from the previous studies show that the tidal current along the mouth of Jiaozhou Bay (JZB) appears to have weakened, whereas the spatial asymmetry (stronger flooding in the north region and stronger ebbing in the south region) has remained nearly unchanged during the past several decades of large‐scale land reclamation. This study is conducted to explain the underlying dynamics for this phenomenon. The analytic evaluation of the tidal motion indicates that the tidal current in a small coastal bay such as the JZB is linearly proportional to its length (L), if L is far less than one‐quarter of the tidal wave length. This relation suggests that the decrease in tidal current speed in JZB mouth results from the land reclamation within the Bay. Also, the relationship between bay areas and tidal current along the JZB mouth can be derived. The results of this simple theoretical method for predicting the change in mean tidal current amplitude after the land reclamation largely agree with previous three‐dimensional (3‐D) modeling studies. It is also found that the spatial asymmetry of the tidal current along the JZB mouth is controlled by the sharp headland (the local factor). The unchanged shoreline around the headland leads to the stable spatial asymmetry of the tidal current. The weaker tidal current can explain the weaker residual current, and the unchanged asymmetry of the tidal current explains the unaltered pattern of inflow over the north region and outflow over the south region for the tidally induced residual current along the JZB mouth.