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The dataset compiles pigment content, absorptance data, photosynthetic parameters and primary production data as proxies for summertime photoacclimation of the temperate intertidal eelgrass Zostera marina after a 25-day exposure to a natural light intensity gradient (6, 36, 74, 133, 355, 503 and 860 µmol photons/m²/s) under laboratory conditions at the Pointe-au-Père research station, East Rimouski, Quebec, Canada. The data bundle contains: 1) photosynthetic and total absorptance data at the end of the experiment, which respectively represent the fraction of incident visible light absorbed by the photosynthetic tissues corrected and not corrected for non-photosynthetic absorption; 2) pigment content at the end of the experiment, which includes chlorophyll a and b and total carotenoids contents; 3) photosynthetic parameters obtained by Rapid Light Curves (RLC) on days 5 and 25, including photosynthetic apparatus efficiency (alpha), capacity (ETRmax) and saturation (Ek); 4) whole shoot primary production at the end of the experiment, which was calculated from oxygen fluxes under light and dark conditions, and normalized by leaf surface.

In British Columbia, one of the main negative impacts on salmonid habitat is the production of fine sediments generated by forest roads or other human activities. Given this concern, this study’s main objective was to develop a quantitative framework for estimating effects of extreme suspended-sediment events caused by forest road construction and use on populations of chinook (Oncorhynchus tshawytscha) and coho salmon (Oncorhynchus kisutch) in a medium-sized coastal watershed of the lower Fraser River. The framework incorporates existing knowledge of sediment production by forest roads to make a quantitative link between traffic levels and physiological responses of salmonids. The results suggest that extreme sedimentation events generated by heavy traffic levels negatively affect populations of chinook and coho. Population numbers declined proportionally to the elevated levels of suspended sediments concentrations following a non-linear trend in which Chinook salmon are more vulnerable to the deleterious effects of sediments than coho salmon.

My special thanks go to my research director, Mr Roger Nkambou, professor in the department of computer science at UQÀM, and my research co-director, Ms Jacqueline Bourdeau, professor at the Télé-Université. As well, I especially thank Professor Froduald Kabanza, Dr. Jean Roy and Dr Rolland Yatchou.; Ph. D. Thesis in cognitive informatics, Department of computer sciences, Unversité du Québec à Montréal (UQÀM), Canada; In an Intelligent Tutoring System (ITS), issues related to the design and the implementation of the cognitive diagnosis (DC) of learner's behavior is addressed intuitively according to the specific goals of this STI. From a purely operational viewpoint, this approach is not really bad since the STIs arising from it, "work". However, when it comes to give to DC a pedagogical dimension in the human tutors, a look into perspective on more fundamental considerations promotes reflection in this direction. This thesis formulates, formalizes and implements explicitly a “pro-pedagogical” dimension of the DC in the STI.

Almost all research output includes tables, diagrams, photographs and even sketches, and papers within HCI typically take advantage of including these figures in their files. However the space given to non-diagrammatical or tabular figures is often small, even in papers that primarily concern themselves with visual output. The reason for this might be the publishing models employed in most proceedings and journals: Despite moving to a digital format which is unhindered by page count or physical cost, there remains a somewhat arbitrary limitation on page count. Recent moves by ACM SIGCHI and others to remove references from the maximum page count suggest that there is movement on this, however images remain firmly within the limits of the text. We propose that images should be celebrated – not penalised – and call for not only the adoption of the Pictorials format in CHI, but for images to be removed from page counts in order to encourage greater transparency of process in HCI research.

The pathophysiology of essential tremor (ET) is not clearly understood but is thought to involve multiple brain regions. The purpose of this study was to describe in greater detail head tremor in ET and to investigate the possible relationship between head and hand tremor. Ten ET subjects were recruited (1 male, 9 female) and compared to three control subjects (1 male, 2 female). Head and hand tremors were recorded simultaneously with surface electromyography (EMG) of the wrist extensors and various neck muscles, laser displacement sensors (hand tremor), a load cell (hand tremor) and an accelerometer (head tremor). While seated, subjects performed four tasks: 1) constant force (10% maximum) wrist extensions (with and without visual feedback); maintenance of the hands in a horizontal posture against gravity while 2) seated upright in a chair, 3) seated in a reclined chair (20° backward, head not supported); and 4) seated upright in a chair and producing steady submaximal hip adduction forces. Head tremor spectral peaks were found between 3.5 and 7 Hz in neck muscle EMG and the accelerometer signal. Wrist tremor (EMG and kinematic data) was slightly higher in frequency with a range of 4 -10 Hz. Of the ten ET subjects recruited for this study, 60% (n = 6) demonstrated significant levels of coherence (p < 0.05) in at least one neck-wrist muscle comparison at the fundamental frequency of their tremor. The results demonstrated an obvious bias of the trapezius descendens (TD) muscles over the more axial neck muscles to demonstrate significant coherence with the extensor carpi radialis (ECR) muscles. Of the six neck muscles investigated, the SPLs and the SCMs were commonly driven at the same frequencies (change in frequency < 0.5), although this seldom resulted in coherence. There is indication that the oscillatory activity driving more distal muscles is different from that in the SPL and the SCM. Due to the multifunctional nature of the TD, it may be the recipient of two descending neural commands. These commands may each be of a different oscillatory frequency originating from different central oscillators.

Durable adhesion of repair material on concrete substrate requires compatibility between the materials to be bonded. There are four main compatibility components to be addressed in any concrete repair scenario: dimensional, permeability, chemical and electrochemical compatibility. Among those, dimensional compatibility is often prevalent: while a cement-base repair material inevitably undergoes shrinkage, the substrate opposes to its free movement, a situation that can lead to cracking and, subsequently, promote debonding. Besides, an essential requirement for bond development is the creation of the interface itself: the intimate contact between the repair system and concrete substrate is required in order to maximize adhesion. Adequate compaction of the new layer is consequently one of the main parameters that will govern the quality of the bond: sufficient vibration or specific rheological properties for the repair material are needed. Self-Compacting Repair Mortar (SCRM) can be advantageously used in many repair situations. Limestone fillers seem to offer interesting advantages as addition to these repair materials as they increase the workability of the final product. Several materials have been tested and characterised by means of a physical, chemical and mechanical characterization test program: specific attention has been given to water demand and superplasticizer efficiency.

The Cowichan River fall-run Chinook salmon (Oncorhynchus tshawytscha) population has been a serious conservation concern since 1997. I developed a stochastic life-history simulation model of both hatchery-origin and naturally-spawning Chinook in this system to evaluate management options involving specific harvest and hatchery brood-take rates. Ocean harvest was more influential than supplementation on the stock’s abundance. My results suggest that this stock’s recovery is unlikely to occur under current poor marine survival conditions and either the status-quo management strategy or lower harvest rates that managers are likely to find realistic. Model outputs also allowed analysis of trade-offs among management objectives involving conservation, Food, Social and Ceremonial and ocean harvests, and hatchery operations. Analyses of these performance indicators showed that under poor or intermediate marine survival conditions, the best management strategies (according to most indicators, including ocean harvest) involved the lowest ocean harvest rates examined here, i.e., 30% or 40% annually.

This work reports on experiments in which antihydrogen atoms have been produced in cryogenic Penning traps from antiproton and positron plasmas by two different methods and on experiments that have been carried out subsequently in order to investigate the antihydrogen atoms. By the first method antihydrogen atoms have been formed during the process of positron cooling of antiprotons in so called nested Penning traps and detected via a field ionization method. A linear dependence of the number of detected antihydrogen atoms on the number of positrons has been found. A measurement of the state distribution has revealed that the antihydrogen atoms are formed in highly excited states. This suggests along with the high production rate that the antihydrogen atoms are formed by three-body recombination processes and subsequent collisional deexcitations. However current theory cannot yet account for the measured state distribution. Typical radii of the detected antihydrogen atoms lie in the range between 0.4 µm and 0.15 µm. The deepest bound antihydrogen atoms have radii below 0.1 µm. Antihydrogen atoms with that size have chaotic positron orbits so that for the first time antihydrogen atoms have been detected that cannot be described by the GCA-model. The kinetic energy of the weakest bound antihydrogen atoms has been measured to about 200 meV, which corresponds to an antihydrogen velocity of approximately 6200 m/s. A simple model suggests that these atoms are formed from only one deexcitation collision and methods that might lead to a decrease of the antihydrogen velocity are presented. By the second method antihydrogen atoms have been synthesized in charge-exchange processes. Lasers are used to produce a Rydberg cesium beam within the cryogenic Penning trap that collides with trapped positrons so that Rydberg positronium atoms are formed via charge-exchange reactions. Due to their charge neutrality the Rydberg positronium atoms are free to leave the positron trapping region. The Rydberg positronium atoms that collide with nearby stored antiprotons form antihydrogen atoms in charge-exchange reactions. So far, 14 +/- 4 antihydrogen atoms have been detected background-free via a field-ionization method. The antihydrogen atoms produced via the two-step charge-exchange mechanism are expected to have a temperature of 4.2 K, the temperature of the antiprotons from which they are formed. A method is proposed by which the antihydrogen temperature can be determined with an accuracy of better than 1 K from a measurement of the time delay between antihydrogen annihilation events and the laser pulse that initiates the antihydrogen production via the production of Rydberg cesium atoms. First experiments have been carried out during the last days of the 2004 beam time, but the number of detected antihydrogen annihilations has been too low for a determination of the antihydrogen temperature. Trapped antiprotons have been directly exposed to laser light delivered by a Titanium:Sapphire laser in order to investigate if the laser light causes any loss on the trapped antiprotons. Experiments have shown that no extra loss occurs for laser powers of less than 590 mW. This is an important result against the background of the future plan to confine antihydrogen atoms in a combined Penning-Ioffe trap and then to carry out laser spectroscopy on these atoms, since it reveals that laser light does not cause an increase of the pressure in the trapping region to the extend that annihilations with the background gas become noticeable. The ATRAP Collaboration plans to precisely investigate antihydrogen atoms. The ultimate goal is to test the CPT-theorem by a high precision measurement of the 1S-2S transition of antihydrogen and a comparison with the precisely known value of the corresponding transition in hydrogen. This thesis presents the achievement of the first step towards this challenging goal: the production of cold antihydrogen itself.

This article is a summary of recent Open Access activity in Canada, focusing on policies and mandates, repositories, and initiatives in libraries.

This study aims to design a new warehouse layout as a solution to the warehouse’s main problem: lack of space to store all the materials in stock. Besides the existing warehouse building, which currently presents an unsuitable layout for the storage of large volumes, there is a second area right next to the first to increase the storage area. The two buildings were re-dimensioned to accommodate a great quantity of stock, enabling one to transform the warehouse building into an industrial warehouse with appropriate storage methods. The final layout increased the storage area by 64%, from a total of 1.471,41 m2 to 2.414,22 m2 overall.