International Space Station. Credit: NASA Image

It now appears likely that the mission of the International Space Station (ISS) will be continued through 2020 (See the Augustine Scenarios). And following NASA’s announcement in September of the release of the report on “International Space Station Science Research Accomplishments During the Assembly Years: An Analysis of Results from 2000-2008″, now would be a good time to look back on the scientific accomplishments so far, and to look ahead. Part I The major areas of research include: Technology Development for Exploration Physical Sciences in Microgravity Biological Sciences in Microgravity Human Research Program Observing the Earth and Educational Activities Science from International Space Station Observations

Following launch of the Russian Zarya module in 1998, and before human occupation began in 2000, several experiments were conducted:

• Protein Crystal Growth – Enhanced Gaseous Nitrogen Dewar (PCG-EGN)
• Commercial Generic Bioprocessing Apparatus: Kidney Cell Gene Expression (CGBA-KCGE) and Synaptogenesis in Microgravity (CGBA-SM)
• Incidence of Latent Virus Shedding During Space Flight (Latent Virus)
• International Space Station Acoustics Measurement Program (ISS Acoustics)

One of the most exciting results reported from ISS research is the confirmation that common pathogens change and become more virulent during space flight, performed in September 2006. This has important implications for extended human missions. It is also a target for additional research.

During the time covered by this report, steady growth in publications associated with ISS research has occurred, as shown in the graph to the right. What have been the major research results in each of the six areas discussed in the report? Technology Development for Exploration One of the most important concerns of any space based operation has to be air quality. Therefore, the experiments with the “Analyzing Interferometer for Ambient Air” (ANITA) instrument will prove crucial to future explorers. “ANITA was calibrated to simultaneously monitor 32 gaseous contaminants (including formaldehyde, ammonia, and carbon monoxide (CO)) at low as parts per million levels in the ISS atmosphere. The hardware design—a quasi on-line, fast-time resolution gas analyzer—allowed air quality to be analyzed in near real time.”

Credit: NASA Image

As an example of the importance of these capabilities, the report notes that “ANITA was used in mid 2008 to detect a Freon leak (Khladon 218) from the Russian air conditioner, and to monitor the timeline of Freon concentrations with CDRA operations and shuttle docking. The ANITA data helped to determine that the zeolite bed in the CDRA was not effective in scrubbing the Freon leak, but that diluting the ISS air after the docking with the shuttle substantially reduced the level of Freon” (p18).

Other research topics include:

• The Active Rack Isolation System (ARIS), which protects equipment by absorbing the shock of motion before it can affect an experiment.
• The Smoke and Aerosol Measurement Experiment (SAME), which is planned to gather particulate size information on ISS. It is known that fires in microgravity produce smoke particles that are larger than on Earth. Being able to distinguish between smoke and other particles on ISS is important.
• “The elastic memory composite hinge (EMCH) experiment provided test data on new materials that will further space hardware technology. This technology may eliminate the need for highly complex deployment mechanisms by providing a simpler, lightweight alternative to mechanical hinges. EMCH builds on the previous space shuttle experiment, lightweight flexible solar array hinge (LFSAH) that was flown on STS-93″ (p 22).
• “The In-SPACE Soldering Experiment (ISSI) is another payload that was rapidly developed after the Columbia accident to provide a lowmass experiment using hardware already on board station. It was designed to promote understanding of joining techniques, shape equilibrium, wetting phenomena, and micro-structural development in space” (p 23).

Physical Sciences in Microgravity

While Technological Development is important for space exploration, pure research also has a place on the ISS. Protein crystal growth, fluid physics and materials science are being researched:

• The Advanced Protein Crystallization Facility (APCF) can support three crystal-growth methods: liquid-liquid diffusion, vapor diffusion, and dialysis. In the vapor diffusion method, a crystal forms in a protein solution as a precipitant draws moisture in a surrounding reservoir. In the dialysis method, salt draws moisture away from the protein solution via a membrane separating the two and forming crystals. Initial analysis of the crystals that were returned from station supports the findings of earlier APCF flights: comparative crystallographic analysis indicates that space-grown crystals are superior in every way to control-group crystals that are grown on Earth under identical conditions (p 47).
• The Binary Colloidal Alloy Test hardware supported “three investigations in which ISS crews photographed samples of colloidal particles (tiny nanoscale spheres suspended in liquid) to document liquid/gas phase changes, growth of binary crystals, and the formation of colloidal crystals that were confined to a surface. Colloids are small enough that in a microgravity environment without sedimentation and convection, they behave much as atoms. By controlling aspects of colloidal mixtures, they can be used to model all sorts of phenomena” (p 49).
• Protein Crystal Growth-Enhanced Gaseous Nitrogen (PCG-EGN) was designed to produce crystals of various biological compunds. Also, some 500 student preparations were made as part of an education program to teach students about crystallization, crystallography methods and the impact of crystallography on medicine and biotechnology. A significant number of crystallization were successful. Indeed, some of the results produced better data than could be obtained in Earth bound efforts (p 69).

Sometimes, “no” is just as important as “yes”.

Researchers have found that it is possible to grow high-quality protein crystals in the weightlessness of LEO, where gravitational forces will not distort or destroy a crystal’s delicate structure.

The goal of the Dynamically Controlled Protein Crystal Growth (DCPCG) experiment was to control and improve the crystallization process by dynamically controlling the elements that influence crystal growth.

DCPCG was the first flight test of an apparatus that was designed to control the crystal growth process by controlling the rate of evaporation. The apparatus worked on orbit, and crystals were grown for the test proteins; however, the investigators determined that the growth could have been better. The same apparatus was used in extensive testing on the ground. Researchers tested a selection of protein solutions, including insulin (a hormone that is produced by the pancreas to regulate the metabolism and use of sugar), serum albumin, and lysozyme (an enzyme that attacks bacteria) and found that a slower evaporation rate yielded better results than a more rapid evaporation rate. While the results of the ground tests were published, the DCPCG experiment investigators did not seek to publish any structures from crystals grown in orbit.

What’s Ahead

In 2008, the European Space Agency’s (ESA’s) Columbus and Japanese Aerospace Exploration Agency’s Kibo scientific modules joining NASA’s Destiny Laboratory. Further, in 2009, the number of crew members increased from three to six. This means that a lot more time is available for research in the future.

New experiments aboard the ISS include a broad range of science, as follows:

• Coordinated human research experiments that collaborate with International Partners’ science objectives and activities, including shared baseline data collection and in-flight sampling, with the goal of understanding integrated causes and effects of changes in the human body.
• Research using new science racks, including the fluids integrated rack (FIR), the combustion integrated rack (CIR), and materials science research rack (MSRR), will enable new experiments exploring combustion, fluid behavior, and heat-dependent crystallization patterns in metal alloys.
• Exploration Technology Development will build from early experiments on materials exposure, smoke generation, liquid fuel management, and environmental monitoring.
• The new Window Observation Research Facility (WORF) will provide capabilities to support remote sensing instruments, enabling Earth Science research that will, for example, document crop health and test the utility of blue-green bands for ocean research.

Part I

A multitude of information can be and is gathered from the world, but oft overlooked is the one thing that gives this planet life. That is light, and more specifically light from the Sun. To many, when the Sun is viewed, this signals that it is time for the day to begin and for our work, school, or daily routine to commence. But what is the Sun made of? For that matter, what are stars made of in general?

This question began to be seriously considered and studied during the 19th century. Several scientists in the early 19th century began to contribute to early spectroscopy, which, historically, is the use of visible light dispersed according to its wavelength by a prism. This study led to the discovery by Charles Wheatstone that different metals could be easily distinguished by the different bright lines in the emission spectra of their sparks. This discovery launched the study of spectral analysis.

Diffusion of light

In 1854, a scientist named David Alter published an article that included the spectral radiance, which is the measurement that describes the amount of light that passes through or is emitted from a particular area and falls within a given angle in a specific direction, of twelve different metals. He went on to apply this in a later article to six different gases as well. This article contains a paragraph where he envisioned the application of spectrum analysis to astronomy in regards to the combustion of shooting stars or meteors.

Each element has a spectral fingerprint that is specific to that element. This is detected by analyzing either the emission or the absorption spectrum. The emission spectrum is used when the element being analyzed produces light, such as the spark from a combusting metal or a star. The absorption spectrum is the light that is left over after passing through a solid or gas. The cataloging of elements found on Earth has enabled scientists to analyze the spectral fingerprint of visible stars in our galaxy. This in turn, allows scientists to understand what elements make up specific stars.

Spectral analysis of our sun has yielded the elemental make up of our life-giving star. The sun, for the most part is hydrogen. In fact, it is 70% hydrogen by mass. The other main element found within the Sun is helium, which was actually discovered through spectral analysis of the sun prior to be found on Earth. The Sun is 28% helium by mass. 1% of the sun is oxygen and the remaining 0.5% contains other elements including, carbon, nitrogen, silicon, magnesium, neon, iron, and sulfur. The Sun is about 4.5 billion years old and still has about 5 billion years worth of hydrogen left to burn.

Without spectral analysis, it would be impossible to classify the elemental make up the Sun and many other stars that have been identified. This science’s impact has allowed humanity to better understand the similarities between the Sun and many other stars within our vast universe down to elemental composition.

References

http://chemistry.about.com/od/geochemistry/a/sunelements.htm

http://imagine.gsfc.nasa.gov/docs/science/how_l1/spectral_what.html

http://curious.astro.cornell.edu/question.php?number=244

It has been a fun summer of blog posts where I reflect upon life through the scope of popular media and celebrity gossip.  However, this past week, my professor Paul Hatala assigned research into decaffeination, and this allowed me to think about how this relates to life as a whole and media at a large.

Decaf is trendy, it's in. http://www.fitsugar.com/1131487

It’s enlightening how the popularity of these drinks have surged into popularity in recent culture.  Decaffeination is the removal of caffeine, the substance responsible for stimulation in the nervous system (Cyldesdale, 1999).  In fact, 12% of total coffee consumption is based on decaf coffee (Cyldesdale, 1999), a continuously increasing number, likely linked to celebrity and “healthy living” influences.  When paparazzi catch Paris Hilton with that cup of decaf in her hand, and Global News lambasts the effects of caffeine, a paradigm shift emerges as more viewers switch their source of intake.  This Dilbert Comic lambasts this emerging paradigm.  The underlying motive may be a sense of conformity, a sense of people to follow in the black and white sense, what they see as right instead of what is wrong.  This diffusion, separation, and transfer of ideas is also the fabric underlying decaffeination.  Before you get into the chemistry, here’s a quick video lambasting the hoopla of decaf coffee.

The principal “European” method is to use a solvent known as methylene chloride, CH₂Cl₂, which is sometimes criticized for being hazardous in large doses (Petrucci, 2007).  Coffee beans are treated with steam first to draw caffeine from the inner bean to the outer surface area, preparing the bean (Sturdivant, 1991).  The solvent may then be applied in a direct method, removing solutes from the beans including caffeine, which diffuses into the solute (Webber, 2008).  Batch processing can be used, where solvent is evaporated through distillation and re-added to a vessel (Cyldesdale, 1999).  This allows more extraction of caffeine until the solvents and beans reach equilibrium as the content of caffeine is so minimal in the beans, it will no longer diffuse out of the shell.  In an indirect process, first the water-soluble caffeine is soaked in water, where it is able to diffuse from the bean into this water (Webber, 2008).  The water is then treated by the methylene chloride, which then allows the caffeine solutes to be transferred this solvent, and the treated water is then forced back through some tube mechanism to return flavours and oils, and then the process is repeated several times like the previous method until caffeine is minimal (Cyldesdale, 1999).  The repetition is required as each stage attains a constant equilibrium, and with La Chatelier’s Principle, by removing the product (removing caffeine through the solvent), the system is shifted to the right (more caffeine is dissolved in water).   The methylene chloride acts a selective solvent, only having reactions with the caffeine molecules, not the flavours or oils (Sturdivant, 1991).  However, another method does not use this selective solvent.

A simplified model of water-processing for decaffeination. (Norr, 2008).

The second method, touted to be the measure of the future, is the Swiss Water Method.  This method uses hot water and steam instead of chemicals (Norr, 2008).  The beans absorb water, opens the cellular structures of the beans, and the caffeine and flavour molecules dissolve to the water (Webber, 2008).  This water is then filtered through charcoal or carbon filters, where the caffeine molecules are trapped, while the flavour molecules remain with the water (Norr, 2008).  The charcoal is pre-treated with sucrose, which helps absorb the caffeine (Cyldesdale, 1999).  This ‘flavour-water’ extract is added to new coffee-beans, extracting only caffeine (Norr, 2008).  This principle works because the solution is super-satured with flavour, and thus there is equilibrium between the flavour molecules, so solely caffeine will be extracted from the beans.  High temperatures (from 70-100°C) are used specifically to supplement this process to increase the kinetic energy of molecules and ability to diffuse.

But what does this all mean?  How does diffusion relate back to conformity:  This all comes back to the underlying principle of the masses.  Think of these caffeine solutes leaving their safe shell to experience new worlds.  They are being led into a new system by a strong solvent, beckoning to accept them.  As they experience a new world, they are essentially being tainted, leaving their original home permanently, the coffee bean.  The solutes WANT to diffuse, reach equilibrium, pass that concentration gradient.  People behave in a likewise manner, moving to areas where there is the freedom to explore, with ability to separate themselves from the sheep.  By simply obeying the laws of physics and chemistry, they follow the concentration gradient to spread from those similar.  But in the end, aren’t these people the sheep controlled by physical forces?  Try to imagine a utopian society where everyone shared the same belief, and these beliefs were perfect.  This can never happen on the basis of this ‘sociological diffusion.’  People wish to separate and form their unique niche in society.  Ideas, opinions, and everything diffuse.

It's easy to understand why people diffuse to popular culture. (Still from Transformers 2)

Yet, a gradient can only go in one direction or the other, a reaction can only go forwards or backwards.  Fundamental chemistry relies on dichotomies, and perhaps people are prone to view the world in a similar sense, choosing either decaf or caffeinated coffee.  But whereas decaffeination aims for that homogeneity, diffusion in life relies upon heterogeneity.  What I mean by this is that decaffeination presents only one path, only giving the option to stay or not to stay, where an equilibrium appears.  However in life, we have many solvents, many methods, a variety of journeys to embark upon, each leading us to unique ideas.  We should leave that shell to learn and explore, as our original home may restrict how we view the world.  But we should not function merely as chemical forces, following the solvent because the K_sp tells us to, or diffusive forces take us out.  Morals need to be maintained, judgement needs to be kept, and we must incorporate our biological thought before taking that step to follow.  Equilibrium in life must be achieved!

For me, this equilibrium may be to continue this hobby amidst the stresses of university.  I think it’s time for me to be that 2-4% of caffeine remaining in the decaf coffee, re-evaluating my shell and re-evaluating me in this Christmas break.  And this blog will be the perfect outlet for this introspection.

Peace and Love!!

Works Cited

Cyldesdale, F. (1999, October 21). How is caffeine removed to produce decaffeinated coffee? Scientific American . Retrieved from: http://www.scientificamerican.com/article.cfm?id=how-is-caffeine-removed-t

Norr, S. (2008, July). Where does the Caffeine Go? Tea and Coffee.  Retrieved from: http://www.teaandcoffee.net/0708/feature.htm.

Petrucci, R. (2007). General Chemistry Principles & Modern Applications 9th Edition. Upper Saddle River, New Jersey: Pearson Prentice Hall.

Sturdivant, S. (1991, February 1). Methylene chloride decaffeination: bad process or bad press. Tea & coffee Trade Journal . Retrieved from http://www.allbusiness.com/manufacturing/food-manufacturing-food-coffee-tea/154175-1.html

Webber, R. (2008, September 25). How Do They Remove the Caffeine from Coffee. CHOW Food Media, CBS.  Retrieved from http://www.chow.com/stories/11330

We often hear of new words and phrases being created or recycled to create new meaning. Whether this be for a new behaviour or to describe a new one.

If we take a look we can see that these can often be associated or connected to new media activities or actions.

Take the gaming community. When a gamer beats a component they win. This can be considered as ownage. A concept to represent domination of skill and supremacy against other players.

Or take txt talk. Phrases such as LOL (laugh out loud), BRB (be right back) or CBA (can’t be arsed) are widely understood by the younger mobile messaging community.

These phrases were not commonly used outside of this media but have been adopted as a representation of expression by certain users to signify emotion. What do i mean. Well take LOL, most users will actually not laugh out loud when reading the message but will use the phrase to show that they found a comment funny!

 The medium of mobiles with its increased understanding by users of the technology and its ease of use will enhance the diffusion of its adoption and frequency of use (linked to the diffusion of innovation). This could provide an indication as to why certain expressions and phrases have become popular by the media they are communicated within as the medium is used and interacted with more by its users.

What this indirectly suggests is that it is not entirely down to the phrase and its meaning but the media platform that it is communicated on, supporting the theory of the media is the message.

So when creating a new concept/phrase we must look at the relevance of the media platform and the interaction that the user has with the medium to enhance its likelyhood of adoption and use.

Retrouvez ci-dessous les 33ème épisode de Fullmetal Alchemist: Brotherhood.

Sources : Dybex@Dailymotion – Random Curiosity

PHILOSOPHY SHOULD LEAD SCIENCE

PHOTOSYNTHESIS

 Any high school student will tell you that leaves of plants use carbon dioxide of the atmosphere and water absorbed by the roots to make starch in the presence of sunlight for use by the cells of plants. As a layman, certain doubts arose in my mind which I discussed with senior students and a professor in university. I should confess, instead of clearing my mind, it only helped to confirm my thesis that every cell in the plant (except dead cells !) re-uses the CO₂ and H₂0 , released during respiration, for synthesizing starch. This is purely a philosophical conclusion,as I lost touch with the world of science in March 1957 after B.Sc. examination.I shall enumerate some of my points :

1)      The extremely tender, minute root tips are always growing and require continuous supply of starch.In very tall trees,the distance from top leaves to the root tips may be as much as 300 metres.There is no proper mechanism for transport of starch over such distance,unless we can locate different channels for upward movement of water and downward movement of starch in dissolved form, right from root tip to leaf tip and back. Xylem and phloem tissues are mentioned as responsible for this movement,but in trees like teak, jackwood etc all tissues inside the bark except perhaps a thin  layer of cortex, are absolutely dead and impervious to water, being filled with wood oil and compressed by the weight of the trunk. That is why we are able to make furniture,boats,ships etc with wood. Actually, the clever tree is making use of the dead cells as a skeleton-like support for its branches and leaves ,the latter being mercilessly dropped after making use of them!

2)      In Silent Valley in Kerala, I was shown a very tall tree, hollow inside, with two convenient natural holes, one at the bottom and the other at the top. We can see the sky, looking up from the bottom hole! The tree is alive. How is water and starch transported when xylem and phloem are absent?  

3)      In Australia, ring cutting was extensively resorted to, for felling trees. The bark and a small part of cortex was removed by making an eight inch deep cutting round the trunk at the bottom. After about six months, the tree falls down dead. This clearly proves that the outermost live cells are responsible for water transport.

4)      We plant rose cuttings. The cells on one end develop into a shoot and cells on the other side produce roots .Plant cells are remarkably versatile.Every cell can split and produce all chemicals required for making a duplicate cell . It is impossible to believe that a root cell will wait for starch to come from leaves, when raw materials are available as a result of its own respiration, and it has the necessary technical know-how for making even complicated proteins. Do we not re-use waste in a space station? Are we cleverer than plants?

5)      There is no way for a plant cell , except in the leaves, to get rid of CO₂ produced during respiration. When I, earlier, circulated my doubts in this regard, via email,I got only one response .The botanist had only one word-‘diffusion’ to desciribe the process. In the humans, is it enough if we just say ‘respiration’? We study all detailed mechanism in human physiology. In the same way, should we not describe the method used by plants to obtain oxygen and get rid of CO₂? The professor also said the same thing.As adjoining cells are also producing CO₂, how is diffusion possible?The area surrounding the roots will become saturated with CO₂.The root will die. The conclusion is inescapable: cells are recycling water and CO₂ produced during respiration.

6)      When mango fruits are produced in bulk during the season,the number of leaves are actually curtailed! Will farmers curtail production of food grains when it is required in bulk? Laburnum tree becomes almost yellow with flowers in the season, leaves hardly visible. How is starch produced when leaves are reduced?

7)      Bamboo, papaya tree etc are hollow,in the case of the former, there are segments,each one a waterproof compartment . Coconut tree mysteriously carries gallons of water to make toddy. If you cut the tree, not a trace of water is found. Are trees using nano technology?

8)      In my view,the main function of leaves is to pump water up for which lot of energy is required.Naturally,they make large quantities of starch which attracted the attention of botanists who hastily came to the conclusion that only leaves are concerned in this process.

9)      Maximum number of fish thrive in the deep oceans eating planktons which make starch in strata which receive practically no sunlight.

In view of the above, I feel more research is needed before we come to a firm concusion about the mechanism for production of starch and its transportation.

Today, institutions like NASA have all the technical capabilities to study this issue which should not be left to the comparatively ill equipped botanists.

Timbres commémoratifs de Postes Canada

Qui n’a pas entendu parler du 100^e anniversaire des Canadiens de Montréal?
Cette commémoration a été soulignée sous tous ses angles: des livres biographiques aux pièces de monnaies, à l’achat de l’équipe par la famille Molson.
Sous tous ses angles ou presque… il ne manquait que les timbres lenticulaires de Postes Canada!

Pas tout à fait des hologrammes, ces timbres sont des séquences vidéos tirées des archives et sont animées grâce à une technique d’imagerie que l’on nomme Motionstamp^MC. L’illusion est parfaite, on a l’ impression d’assister aux buts historiques de nos héros. Une première canadienne en philathélie.
Voilà une belle utilisation des archives qui rend ces dernières encore plus vivantes!

Émis le 17 octobre dernier, ces timbres rendent hommage aux grands joueurs de l’histoire du Tricolore.
La première série représente les 500^e buts marqués par Maurice Richard en 1957, Jean Béliveau en 1971 et Guy Lafleur en 1983.  On peut voir à quoi ressemble ces timbres animés à travers le reportage de La Presse canadienne. Le premier ministre Stephen Harper a participé au dévoilement de ces timbres en compagnie des joueurs étoiles comme Réjean Houle et Guy Lafleur.

Souhaitons que les Canadiens de Montréal puissent couronner leur anniversaire de fondation en remportant une 25^e coupe Stanley en carrière.

Go Habs Go!

Postes Canada
http://www.postescanada.ca/cpo/mc/aboutus/news/pr/2009/2009_oct_montreal_canadiens.jsf
http://viewer.zmags.com/publication/9960956e#/9960956e/8

Canadiens de Montréal
http://canadiens.nhl.com/club/l_fr/news.htm?id=502517

Ceci est un petit résumé du CCTP, à destination des personnes étranges qui ne prendraient aucun plaisir à la lecture des cahiers des charges…

*Généralités
Le contrat porte sur 450 000 à 500 000 ouvrages (= titres ou =volumes ?) sur 10 ans (art.2)
La numérisation doit commencer dans les 18 mois suivant la notification du marché et les 200 000 premiers ouvrages doivent être numérisés dans les 4 ans (art.3)
Elle a lieu dans un lieu secret situé à moins de 50km de Lyon (art.4)

*Traitement de l’opération

*Google ne numérisera pas une partie des pages, elle peut notamment laisser de côté les pages déchirées et les cartes et documents dépliants (art. 14). Sauf si la BML compte effectuer des scans supplémentaires, cela voudrait dire que la consultation de l’exemplaire numérisé ne suffira pas à une personne intéressée et qu’il faudra tout de même parfois recourir à l’original… qu’on nous refusera puisque l’ouvrage aura été numérisé.

*Les documents seront numérisés à la fois en mode image et texte. Problème : il est seulement indiqué que le logiciel d’OCR doit être “performant”. Le flou dans le vocabulaire, alors qu’il est aisé de parler en pourcentage de caractères reconnus, laisse craindre que ce ne soit guère le cas. En tout cas, pour l’instant, les résultats sont très mauvais sur les typographies du XVIIe s. (art.14)

*Les ouvrages ne seront pas absents plus d’un mois de la BML, ce qui limitera leur indisponibilité pour les lecteurs (art.8)

*Les conditions habituelles de conservation devront être respectées et des précautions sont prises lors du transport et de la numérisation elle-même (art.5-7 et 12)

*La BML accepte étrangement que les fichiers ne leurs soient pas forcément donnés en format TIFF. Le JPEG est accepté !

*Les fichiers remis à la BML ne devront pas comporter de filigrane ou de marque de Google

*Google paye 0,64 euros pour création de méta-données bibliographiques dans la limite de 25 000 titres (art. 16). Manière de pallier les éventuelles insuffisances du catalogue de la BML ?

*Un contrôle qualité a lieu mais il n’est pas contraignant : Google ne renumérise que si les deux parties en sont d’accord (art. 18), de même pour la qualité de la mise en ligne.

*Absolument tous les coûts sont à la charge de Google (art. 19)

*Consultation de la bibliothèque numérique

*Google remet à la Ville de Lyon un exemplaire des fichiers créés, accompagnés des métadonnées afférentes.

*La consultation est prévue selon deux modalités (art. 20). D’une part les fichiers seront intégrés à Google Recherche de livres. D’autre part Google propose à la BML une solution clef en main pour la consultation sur internet des ouvrages numérisés. L’entreprise états-unienne décide alors de tout : “Les fonctionnalités, le design et le contenu de ce service hébergé restent entièrement sous le contrôle du titulaire [Google]“
Seule assurance, une recherche avancée est prévue et l’on pourra rechercher à la fois en plein texte et par les métadonnées bibliographiques. Ce portail doit fonctionner 6 mois après le début des opérations de numérisation, donc en 2010.

*Un lien sera établi vers le catalogue de la BML (art. 21)

*Clauses juridiques

*Google a l’exclusivité de la numérisation sur les livres qui lui sont confiés (sauf exception, au cas par cas, dans le cadre des services habituels au lecteur) (art. 24). Il a également l’exclusivité de leur exploitation commerciale pour un temps donné.

*La Ville de Lyon dispose librement des fichiers et des métadonnées attachées, et peut en faire ce qu’elle veut, notamment créer sa propre bibliothèque numérique. Elle peut permettre des téléchargements de pages à l’unité mais doit mettre en oeuvre des solutions pour s’opposer au téléchargement de “parties substantielles” de la base.
Cela pose le problème du statut juridiques des scans. Si des droits existent sur les métadonnées et sur l’ensemble de la bibliothèque en tant que base de données, je ne vois pas de quels droits Google pourrait disposer sur les scans eux-mêmes.

*La Ville de Lyon peut conclure des partenariats à des fins éducatives ou de recherche. Si elle veut coopérer à plus grande échelle, elle doit demander l’accord de Google

VU a le plaisir d’accueillir cette semaine Serge Tousignant dans ses espaces de production. L’artiste effectue une résidence de création lui permettant de travailler sur ses Chroniques d’un été dans les montagnes vertes, une série de photographie produite l’été dernier et qui sera exposée à VU  du 26 mars au 25 avril 2010.

Né à Montréal en 1942, Serge Tousignant débute sa carrière artistique dans les années 1960 et, au cours de la décennie suivante, adopte la photographie comme médium de prédilection. Artiste d’envergure internationale, Serge Tousignant a enseigné la photographie à l’Université de Montréal de 1974 à 2002. Ses œuvres figurent dans plusieurs collections publiques canadiennes et étrangères, notamment celles du Musée des Beaux-Arts du Canada à Ottawa et la Tate Gallery à Londres.

Image: André Barrette, 2009.

Le centre VU félicite Jacynthe Carrier, récipiendaire du Prix Videre Relève 2009. Du 27 mars au 26 avril 2009, Jacynthe Carrier présentait à VU l’exposition Scènes de genres, série photographique révélant un théâtre insolite où des personnages aux allures de survivants post-apocalyptiques occupent l’espace quasi intemporel d’un terrain vague, mimant leur difficulté à vivre dans une zone contraignante, loin de leur réalité. Ce travail était le fruit d’une résidence de création effectuée par l’artiste dans les espaces de production du centre VU.

Artiste de la relève de Québec, Jacynthe Carrier détient un baccalauréat en arts plastiques et médiatiques de l’UQAM et effectue présentement une maîtrise en photographie à l’Université Concordia. Son travail photographique ou vidéographique a notamment été exposé à la Galerie Lilian Rodriguez de Montréal, à la Manif d’art 4 de Québec, ainsi qu’au centre Caravansérail de Rimouski.

Images: Ève Cadieux et André Barrette, 2009.

Bien souvent les centre de documentation surveillent des newsletters, les publications des sites, les revues, les périodiques. Au CERTU , il y a deux produits-phares. Le premier est le “panorama des revues” qui se présente avec une série d’articles qui sont référencés par titres, par dates, numéros et pagination sans le texte intégral. Il n’y a que les mots importants qui sont surlignés en gras. Et il y a une petite spécificité, c’est que les périodiques ne sont pas tous conservés, le panorama indique ou ont été envoyés ces périodiques.

Le CERTU a un nombre de périodiques important. Il envoie ces périodiques aux lecteurs une fois par semaine. Cependant les articles périodiques présentés sur le web représentent une petite partie du panorama. Ils récupèrent quelquefois des articles intégraux avec leurs photocopies.

La deuxième chose qui est pratiquée généralement dans la veille est une diffusion sélective de l’information, c’est-à dire qu’ils regroupent des articles sur des sujets un peu particulier. Le CERTU l’envoie directement à la personne qui est concernée. Ils écrivent également des livres pour expliquer aux personnes comment faire de la veille.

De manière générale, la veille est chargée de dépouiller les informations reçues, se renseigner sur les activités de son organisme (pour l’URIOPSS) en vue d’adapter sa veille. Il y a ensuite les alertes et les anticipations et enfin la diffusion,  la communication.

Playing around with food coloring and watercolor in a glass to see the various effects of diffusion. Science!

Music: Obokuri Eeumi, Asazaki Ikue
Program: Final Cut Express

PS. This video lasts 1:20 but for some reason when I converted it from Final Cut, it kept on creating a file that lasts 2:26…

La hermosa canción de la publicidad de Fernet Branca me inspiró hacer un vídeo de difusión. La canción se llama Obokuri Eeumi, y la canta la japonesa Asazaki Ikue. Estaba jugando con acuarela y color para comida en un vaso para ver los efectos de difusión. Espero que lo disfruten!

Représentant des ventes de Ford/Mercury. Salon de l’automobile, Place Bonaventure, Montréal. Janvier 1973, tirée dans les années 1970. Épreuve à la gélatine argentique. Collection de l’artiste. Photo par Gabor Szilasi.

Sur le site internet du Musée des beaux-arts du Canada, on présente l’exposition des photos de Gabor Szilasi, L’éloquence du quotidien, dans les termes suivants :

Au cours des 50 dernières années, Gabor Szilasi a créé l’un des corpus photographiques les plus significatifs et les plus déterminants au Canada. Il comprend notamment des portraits environnementaux, des scènes de la vie familiale, urbaine et commerciale de Montréal et de Budapest ainsi que des images du Québec rural. Ses images attestent une foi indéfectible en les valeurs humaniste et documentaire de la photographie. Cette exposition de 124 photographies célèbre l’accomplissement de Szilasi et révèle la nature de sa vision artistique à travers ses observations de la vie urbaine et rurale ainsi qu’à travers ses explorations des liens entre la culture et la communauté. Afin de mieux cerner l’évolution et la portée du travail de Szilasi, cette rétrospective propose, côte à côte, des photos emblématiques ou plus diffusées et des images moins connues ou encore inédites.

Exposition organisée par le Musée canadien de la photographie contemporaine et le Musée d’art de Joliette.

L’exposition tombe pile. Gabor Szilasi vient de recevoir du Gouvernement du Québec le prix Paul-Émile Borduas qui récompense l’ensemble de son oeuvre. (http://www.prixduquebec.gouv.qc.ca/miseajour.html). Pour les Montréalais, soulignons que l’exposition L’éloquence du quotidien sera présentée dans la métropole en 2011 au Musée McCord.

Pour l’instant, on peut la voir au Musée des beaux-arts du Canada à Ottawa. Jusqu’au 17 janvier 2010.

Retrouvez ci-dessous les 32ème épisode de Fullmetal Alchemist: Brotherhood.

Sources : Dybex@Dailymotion – Random Curiosity

Chez Publications Québec, un album de photos d’archives attire l’attention, c’est L’aventure de l’électricité 1880-1963. Il s’agit du 18e titre dans la remarquable collection Aux limites de la mémoire. Les auteures, Caroline Cholette et Caroline Rouleau, toutes deux archivistes à Hydro-Québec, ont su tirer profit des richesses des fonds d’archives des compagnies d’électricité nationalisées. Elles ont complété leur abondante cueillette de documents en se tournant vers des fonds d’autres services d’archives.

Au cours des dernières années, Fides a fait le bonheur de ses lecteurs en leur offrant en rafale trois magnifiques ouvrages d’histoire tout en archives,  Une Histoire du Québec en photos (2006), Une Histoire des Québécoises en photos (2007), Une Histoire des hommes québécois en photos (2008), signés par Hélène-Andrée Bizier. La maison d’édition n’a pas perdu la main dans la production d’albums de photos d’archives et nous revient cet automne avec Vivre l’hiver au Québec de Normand Cazelais. L’éditeur parle d’un livre «qui invite au voyage dans le temps et dans les régions du Québec, ce Québec où l’hiver n’est jamais bien loin». Il a puisé abondamment dans les fonds d’archives photographiques de plusieurs services d’archives.

Vous cherchez des idées de cadeaux pour Noël ?

My very first day as a graduate student was a pretty embarrassing one.  I had arranged to arrive at the university in May, three months before the beginning of my semester, in order to spend the summer as a research assistant for the professor who would later become my adviser.  I actually first met my adviser in the men’s room, where I had stopped on my way to his office.  I couldn’t handle the uncomfortableness of introducing myself during an unfortunate first meeting in the bathroom, so I pretended not to recognize him.  Of course, that strategy worked out fine for the moment, but it made the real introduction two minutes later significantly more awkward.

Anyway, the truly embarrassing part came during the discussion that followed my introduction.  My adviser started asking me physics questions to see how well I understood various topics.  I don’t really remember any of the questions, but I do remember that I did an absolutely horrible job of answering them.  He was talking about topics I had learned — mostly classical physics, E&M, and quantum mechanics — but he talked about them in a way that seemed surprising and foreign to me.  Clearly, he had a more advanced way of thinking about these things, one which allowed him to manipulate them conceptually in his mind without doing the kind of formal solutions that always accompany intro-level physics classes.  At the end of our discussion he pronounced his verdict in a painfully forthright way: “Clearly you are not ready for research yet.”  My adviser has never been much for tactful withholding of opinion.

The following month proceeded something like this: I would go to his office in the morning and he would give me a problem to work on.   I would spend the afternoon and evening reading through my old textbooks and lecture notes and trying to piece together a reasonable solution, usually using the direct and formal mechanisms I had learned as an undergraduate.  The next morning I would bring my big solution to his office and present my result (the usual evaluation: you’re kind of right, but not completely right).  Then he would show me how to solve the problem with one diagram and three lines of algebra, give me another problem to work on, and the cycle would repeat.

If I have any “intuition” in physics, it was only developed through a painful and somewhat embarrassing process like this one.  Sometimes I think that to be a scientist is to live in constant fear of embarrassing yourself.

Anyway, in this post I want to discuss one of my very first problems from that summer.  It’s kind of fun, in the sense that the solution is clever, widely applicable, and doesn’t take a lot of specialized knowledge to understand.  It’s also the problem that introduced me to one of the most important strategies in physics: solving by analogy.

The bug zapper problem

Here is the problem, as my adviser posed it to me:

Some very large volume is filled with small, randomly-diffusing objects.  In the middle of the volume is a big sphere.  Whenever one of the random diffusers happens to run into the sphere, it gets absorbed.  If the density of diffusers far from the sphere is , what is the rate at which diffusers are absorbed into the sphere?

Just to give you a better way of imagining the problem, here is how I re-stated the problem to myself:

A spherical bug zapper is hanging from a tree in the middle of the jungle.  The jungle has some density of mosquitoes , which fly around randomly (and are not particularly attracted to the bug zapper).  Whenever a mosquito runs into the bug zapper, it is killed.  On average, how many mosquitoes are killed every minute?

It was only later that I discovered that this is actually sort of a famous problem: the answer is called the Smoluchowski diffusion rate.  It is used for things like predicting reaction rates in living cells, where randomly-diffusing proteins need to find their target sites within the cell.

Believe it or not, the “bug zapper problem” is a problem about fields.  Specifically, it is a problem about a “field” of mosquitoes which fills the space around the bug zapper.  At a given distance from the center of the bug zapper, there will be some average density of mosquitoes.  Far from the bug zapper, this density approaches .  In the immediate vicinity of the bug zapper, the density of mosquitoes should be somewhat smaller, since mosquitoes in that area are being killed off.  You can also think of it like this: at some point immediately to the right of the bug zapper, there are no mosquitoes approaching from the left.  So the number of mosquitoes at this point must be somewhat reduced, since at most points there are mosquitoes approaching from all directions.

I imagine the “mosquito field” to look like this:

Here, the vertical direction (and the color) represents the mosquito density as a function of position (the horizontal directions).  The circle in the center of the plot is where the bug zapper is: the density of mosquitoes is zero there.  The overall density continuously approaches zero as you come to the surface of the bug zapper.

Fick’s Law

“Nature abhors a vacuum” is a pretty famous rule-of-thumb in science.  It means that whenever a region of space is devoid of some material that the surrounding space is filled with, you can expect that the empty region won’t stay empty for long.  For example, if you somehow moved all the air molecules in your room so that they were up against the left wall, and then you released them, you could expect that there would be a sudden rush of air from the left wall toward the empty right side.  The resulting wind would probably even blow you over.  This doesn’t happen because of some mysterious force that pushes air molecules to the right; it’s just the most likely outcome when there are more randomly-moving objects on one side of the room than the other.

In our case we should expect a similar phenomenon: “mosquitoes abhor a vacuum”.  Whenever some portion of space has a higher mosquito density than a neighboring portion, you can expect to see an overall migration of mosquitoes from the more filled place toward the emptier place.  So as the bug zapper removes mosquitoes from the air, there will be a corresponding flux of other mosquitoes radially inward.

In fact, the most general statement of this “abhorring a vacuum” tendency is called “Fick’s Law“.  It gets stated like this: if is the concentration of randomly-moving objects at some point , then whenever there is a concentration gradient there will be a current equal to

.       (1)

The variable here is called the “diffusion coefficient”; it describes how quickly the randomly-diffusing objects are moving and changing direction.  In three dimensions, , where is the average speed of the diffusing objects and is the average time those objects move before changing their direction (say, by 90 degrees).  The minus sign in front of is there to remind you that the current moves toward lower density.

There is one other important law at play here, and this one is even simpler than Fick’s law.  It is this: mosquitoes are not created or destroyed, except at the bug zapper surface.  In other words, there are no sources of new mosquitoes anywhere in the area surrounding the zapper.  Every region in space (except one that includes the bug zapper surface) has as many mosquitoes coming in as going out; there are no nearby sources of mosquito “current”.  Mathematically, the way we express the idea of “sources of current” is by the divergence operator   .  So to say that “there are no sources of new mosquitoes” is to say

.       (2)

When I have taught physics in the past, one of the hardest parts is to convince people that intimidating expressions like stand for relatively simple ideas.

How is a mosquito like the electric potential?

If I had been clever the first time I did this problem, I would have written down equations (1) and (2) and immediately realized that the problem was solved.  That’s because equations (1) and (2) look extremely familiar to anyone who has taken an intermediate-level course on electricity and magnetism.

Equation (1) looks a whole lot like the definition of an electric field based on the electric potential :

.

And equation (2) looks like Gauss’s law, which says that electric field is not created or destroyed in the absence of electric charges:

.

The fact that these equations are so similar is more than just a cute coincidence.  In fact, the equations are exactly the same (aside from one multiplicative constant and some different variable names).  This means that I can use everything I know about electricity and magnetism to help me solve the bug zapper problem.  If I can just translate the bug zapper problem into an analogous electric field problem, then I can look up the answer or solve the simple electric field problem and then translate back to get the real answer to the bug zapper problem.

Let me be more concrete.  The density of mosquitoes is like the electric potential: it fills all of space surrounding an electric charge (the bug zapper).  The current of mosquitoes is like the electric field: it flows from areas of high potential (mosquito density) to areas of low potential.  The absorbing bug zapper is like a big sphere of negative electric charge: it absorbs a current of mosquitoes (electric field).  The rate at which mosquitoes get killed is like the “electric flux”, the total flow of electric field into the sphere.

So I can write the bug zapper problem as an electric field problem like this:

A metal sphere hangs in the middle of a large volume.  Very far from the sphere there is some constant potential .  At the surface of the sphere the potential goes to zero.  What is the flux of electric field into the sphere?

If the problem had been posed to me in this way originally, I would have solved it in 45 seconds.  The tricky part was realizing that the original problem was the same thing.  Now that we know the analogy, we can just solve the electric field problem and make the substitutions according to our analogy.  Once we have the answer, we can replace “electric flux” with “flux of mosquitoes into the bug zapper” and the potential with .

I won’t go into a lot of detail about how to solve the electric field problem.  It’s actually a pretty straightforward application of Gauss’s law: if the difference in potential between the sphere surface and infinity is , then the charge on the sphere must satisfy, where is the radius of the sphere.  The electric flux into the sphere can be found simply from Gauss’s law: (electric flux) .

So that’s it.  Now we just need to replace (electric flux) with (flux of mosquitoes) and with and we have the answer.  It looks like this:

Death rate of mosquitoes = .

This is the famous Smoluchowski diffusion rate.

I should admit here that, if you are reasonably adept at math, this problem probably wouldn’t have been too hard to solve even without the electric field analogy.  But the analogy is still quite powerful.  For example, if the object had been more complicated than a sphere, the math would have gotten hard very quickly.  But the analogy suggests that there is a simple relation between the absorption rate of some particular geometric shape and its capacitance: the amount of charge that can be stored on it at a given electric potential.  In fact, the most general expression for the Smoluchowski diffusion rate is

Diffusion rate = ,

where is the electrical capacitance of a piece of metal with that particular shape and size.  So now if some smart-aleck asks me “well, what if the bug zapper is a cube?”, or a cylinder, or a dodecahedron, I just need to look up already-known values for the capacitance of such objects and I’ll immediately know the answer.  This is the best form of cheating that I know: you show that the hard problem someone is asking you is identical to a hard problem that someone else has already solved, and you look up the answer.  You come away looking clever without having to do much difficult work at all.

In which I claim that all knowledge is interconnected… or something

There is sort of a frightening pressure in graduate school toward extreme specialization.  After all, as a student you’re supposed to write an original thesis on some very advanced and very technical topic.  What this means is that any student who wants to graduate in a reasonable amount of time ends up being hurried to learn as much as possible about their narrow field of study, at the expense of almost all other topics.  The rationalization is that these other topics aren’t relevant somehow to becoming a “professional” in your thesis field.

But I am becoming an increasingly firm believer that learning any piece of physics makes you better prepared to do almost any other piece of physics.  Science, after all, is an enormously complicated network of ideas.  Every theory has a delicate relationship with a myriad of others.  Either it relies upon them for its formulation, or it reproduces them in some limit, or it loses its validity and must yield to them in some other limit.  No idea in this network is allowed to be contradictory with any other idea; they must all fit together like puzzle pieces or threads in an elaborate rug design.  So if you can really understand any part of the network, it will almost certainly give you important clues for better understanding any other part.

In my more grandiose moments, I like think of myself as trying to piece together some enormous puzzle of interconnected ideas, one whose totality constitutes a full description of the universe we live in.  In my less-motivated moments, I remind myself that my adviser needs me to understand things like fluid mechanics and nuclear physics in order to talk about semiconductors.

UPDATE: It occurs to me that Richard Feynman communicated this same sentiment in a much more poetic way in his lecture series The Character of Physical Law:

Nature uses only the longest threads to weave her patterns, so each small piece of her fabric reveals the organization of the entire tapestry.

]]> http://neuraldisarray.wordpress.com/2009/11/17/lowdown-pt1/ Tue, 17 Nov 2009 17:03:40 +0000 neuraldisarray http://neuraldisarray.wordpress.com/2009/11/17/lowdown-pt1/

A few weeks ago I started my work placement, in the electrics department on an ABC comedy — Lowdown, written by Adam Zwar and Amanda Brotchie. Production goes on as we speak, but I’ve already wrapped because I went to Bali for a week and got replaced. Fair enough. But still.. it frustrates me that I couldn’t come back in some capacity, as I was just starting to feel comfortable doing my job before I had to leave, and being on a professional set was an incredibly valuable experience in general. Sucks that I couldn’t stay on for the 6 weeks of shooting. But that’s the way it had to happen, as I’d already locked down other commitments before I knew that I’d have the work attachment. I got a call from Rachel Wilson and rocked up to production the next morning, very short notice, and as a result my working schedule was very erratic.. I tried to fit Lowdown in wherever I could. Anyway, it pains me that I couldn’t work for longer, but regardless, the placement was awesome, so all is well.

Right. So technically I was working as a “lighting assistant”, under the command of Darryl (the gaffer) and Chris (the best boy, but a gaffer in his own right). On a professional shoot there are so many more roles, a much larger and more disciplined hierarchy, and even the lowest roles are occupied by extremely skilled people (I’m not meaning me). Chris gave me great guidance throughout my time on Lowdown, and Darryl made sure I learned from my mistakes. It feels quite harsh at first, very old-school to be verbally punished for slipping up, but it works. You grow a thick skin and make sure to do things better next time.

For now, I want to regurgitate some of the things I’ve learned about lighting while on set.. technical things. I’ll come back to my actual experience of the production at a later date. So.. from here on, it’s all raw information. Enjoy.

HMIs
HMIs are extremely efficient lights. A 1.2K HMI outputs about as much light as a 5K tungsten lamp. Hence you can blast your scene with light without tripping any circuit breakers as you’re well under 2400W. HMIs are also extremely expensive and potentially dangerous — all HMIs are covered by a special sheet of UV-filtering glass. Without this sheet of glass, the light could literally burn your skin off because of the extreme UV output (you can get sores from ~1-2 minutes of direct exposure). Note that UV is on the complete opposite side of the light spectrum in relation to red and infra-red — the primary output of tungsten lights. Hence it follows that HMIs have a stronger output of blue light, running at 5600K (daylight temperature), and are used to mimic sunlight (which is why ARRI’s HMIs are labelled ‘ARRISun’). Also, as the light functions by sending an arc of electricity through mercury vapour, the current would alternate and the light would flicker without a ballast. The ARRI ballasts are relatively small and extremely quiet, but as a rule, the ballast must be connected to the HMI BEFORE it’s plugged into power, or there’s a chance that the ballast explodes.. not pretty. As with other high output lights, HMIs become extremely hot, meaning that if cold rain falls onto the lens or UV-filtering glass, the drastic change in temperature could crack or shatter the glass.. again, not pretty.
Anyway. If someone asks for a 575W HMI PAR to be set up, here’s what you need:
The lamp itself (an ARRIsun 5, or 575, is about the size of a 1K ARRI tungsten lamp, very high output for such low wattage)
The header cable (connects lamp to ballast)
The ballast
The lens box (PAR lamps are used with lenses that disperse the light in various ways. The default setup is to insert the green lens unless otherwise stated)
The stand (generally not a C-stand, something sturdier such as an Avenger combo, made specifically for lights, with two sizes of spigot)
A shotbag

Fluorescents
A 4-ft kino box is freaking heavy. It’s long, unwieldly, and does my back in. Seasoned gaffers and best boys obviously get by, but otherwise it’s a two-man job.
A 4-ft kino runs at 75W per tube on high power. We were using a 4-bank (ie 4 slots for tubes) which ultimately pulls 300W max.. that’s incredibly efficient, considering the light output of the 4-ft tubes. The kino ballasts allow for each tube to be turned on and off individually, so that intensity and colour temperature can be manipulated on the fly. Each kino box comes with a set of tungsten and daylight balanced tubes — you can tell the difference by the colouration at the ends of each tube (blue socket means daylight). A “mixed grille” is where you’ve installed one tungsten tube, then a daylight, then a tungsten, then a daylight. This makes the colour temperature 4400 — right in the middle of 5600 and 3200. It’s important that you alternate between tungsten and daylight tubes to ensure the colour temperature remains even.. or else half the frame will be daylight and the other half tungsten.. you get the picture.

DIY Lighting
On many days of the shoot, Darryl chose to use home-made lights for different purposes. The most popular was the China ball, which is exactly what it sounds like. A regular tungsten bulb inside a china ball to soften the light and spread it in all directions. Good for a fill, but it’s a bitch to gel because you’ve got to get a sheet of CTB inside the ball and clamp it into position without hurting the paper on the outside.. c’est difficile.
Another DIY light I saw on set was the spacelight. It consisted of 4 long incandescent bulbs arranged on a metal cross inside a cylinder of diffusion. You unzip the diffusion like a tent if you need to gel it or change the bulbs. I’m fairly sure that you hang the spacelight high above the scene to provide a reasonably soft toplight and/or fill. It’s a lightweight construction, easy to hang, and provides quite a bit of light as it’s made from 4 redhead bulbs.

Frames, grids and diff
Lowdown is an ABC comedy. Lighting on set required a great deal of softening compared to what I was used to on student films. To simulate the sun, we’d run the big 1.2K HMI behind a mammoth frame of grid or diff. Essentially, you piece together a large metal frame and tie a large square of diffusion material to it, then clamp the frame onto two C-stands and set it up in front of the light. The diffusion material comes in various strengths, and ‘grid’ is different to straight diffusion (or ‘diff’). Softness also varies depending on the distance between frame and light source. The further away you move the frame of diffusion, the greater the softness, but light output lessens dramatically as well. Hence you need huge lights behind the frames if you want to make the scene ultra-soft. And the larger your frame, the softer the lighting quality, hence the huge frames that must be broken down into separate components to fit into the truck

Lighting safety
Shotbag everything.
Gaff down cables where people are likely to walk
When lighting indoors, watch for water sprinklers, and if necessary, tape a cup over each sprinkler to make sure it doesn’t overheat and destroy your equipment. (when taping things to ceilings, stick the tape to your shirt a few times to make sure that it won’t pull paint off the walls)
When lighting outdoors, prepare for rain by pegging rolls of hogwire over lights and ballasts. Hogwire is a robust mesh coated in waterproof resin.. it’s very noisy, so you’ve got to be careful with it during a take.
When hogwiring ballasts, make sure that there’s enough space for them to ‘breathe’.. they need some space around them to prevent overheating.
Don’t touch lightbulbs that draw more than 200W of power. It’s a universal rule.. I previously thought it only applied to Quartz-halogen bulbs, but the deal is that anything drawing so much power will run extremely hot— touching these bulbs impregnates them with natural oils from your skin, and said oils will superheat and may explode the bulb.. so many potential explosions in lighting dept..

ANIMATEUR/ANIMATRICE CENTRE DE RESSOURCES H/F

AU SEIN D’UN CENTRE DE FORMATION, VOUS CAPITALISEREZ, ACTUALISEREZ, CLASSEREZ ET DIFFUSEREZ LES RESSOURCES DOCUMENTAIRES ET INFORMATIQUES DESTINEES AUX STAGIAIRES.VOUS LES ACCUEILLEREZ, LES GUIDEREZ, LES CONSEILLEREZ ET LES ACCOMPAGNEREZ SUR L’UTILISATION DES OUTILS.

Consultez les compétences spécifiques demandées :

- Alimentation des banques de données.

- Banques de données numériques ou textuelles.

- Centre de documentation ou de ressources documentaires.

- Livres.

- Multimédias.

- Périodiques.

Lieu de travail : 61 – ARGENTAN

Type de contrat : CONTRAT A DUREE DETERMINEE DE 6 MOIS

Nature d’offre : CONTRAT ACCOMPAGN. EMPLOI

Expérience : EXIGEE DE 1 AN SI BAC EXP OBLIGATOIRE EN ACCUEIL

Formation et connaissances : NIV. 3 (BAC+2) S. ASSISTANAT SOUHAITE(E) OU NIV. 4 (BAC)

S. ASSISTANAT EXIGE(E) CONNAISSANCES BUREAUTIQUE+INTERNET

Autres connaissances : PRATIQ. TRAIT.TEXTES SOUHAITE(E) PRATIQUE TABLEUR SOUHAITE(E)

Qualification : Employé qualifié

Salaire indicatif : HORAIRE 8,82 Euros (57,86 F)

Durée hebdomadaire de travail : 24H00 HEBDO

Taille de l’entreprise : 3 A 5 SALARIES

Secteur d’activité : FORMATION CONTINUE D’ADULTES

Si cette offre vous intéresse, veuillez adresser par courrier ou par mail, un CV et une lettre de motivation en précisant le numéro de l’offre à :

pôle emploi

POLE EMPLOI ARGENTAN

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ale.argentan@pole-emploi.fr

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Source : ANPE, Numéro d’offre 597986I

http://www2.pole-emploi.fr/espacecandidat/nicola/AfficherOffre.do?reference=597986I&masqueCriteresListe=0

Deux archivistes d’Hydro-Québec, Caroline Cholette et Caroline Rouleau, viennent de faire paraître aux Publications du Québec, dans la remarquable collection Aux limites de la mémoire, un ouvrage de photos sur L’aventure de l’électricité, 1880-1963. Tous ceux et celles qui connaissent la collection, savent à quel point elle contribue à donner au grand public un accès facile au patrimoine photographique archivistique du Québec.

Cette semaine, s’ouvrira à Montréal le Salon du livre. Les Publications du Québec y tiendront, selon leur habitude, un kiosque. Caroline Cholette et Caroline Rouleau y seront vendredi soir 20 novembre et dimanche après-midi le 22, pour autographier leur ouvrage.

Il n’est pas fréquent que des archivistes soient auteurs dans la collection Aux limites de la mémoire. Il vaut la peine de se déplacer pour aller saluer deux collègues qui se distinguent.

La lecture-spectacle offerte par Bibliothèque et Archives nationales du Québec cette semaine soulignera  le dixième anniversaire de décès de l’écrivain et cinéaste Pierre Perrault. On y retracera son itinéraire de poète, de dramaturge, de cinéaste, d’homme de radio et d’essayiste.

BAnQ redonne vie aux archives qu’elle conserve. En s’associant habilement à des gens de théâtre, elle sait transmettre au public des passages marquants de l’oeuvre des créateurs d’ici. Certains se rappelleront de la touchante lecture de textes de Marcel Dubé il y a deux ans au même endroit.

À ne pas manquer.

Auditorium de la Grande Bibliothèque

Mercredi 18 et jeudi 19 novembre 2009, 19h30.

Apocalypse, la 2eme guerre mondiale, cette série télévisée a fait fureur en France en août-septembre de cette année. Plus de 8 millions de téléspectateurs ont suivi fidèlement les six épisodes. Depuis lundi passé, le public québécois y a accès à son tour via TV5 sur le câble.

Cette production est exceptionnelle. L’histoire de la Seconde Guerre mondiale y est racontée exclusivement en archives, 50% étant inédites. Un travail technique spectaculaire de coloration a transformé des films noir et blanc en films couleurs. Le montage des extraits des films est très serré et donne un rythme captivant au récit.

Les deux premiers épisodes ont été présentés en rafale la semaine dernière. Les quatre autres seront livrés au cours des quatre prochains lundis, à 20h00 à TV5.

Ne pas manquer cette fresque historique dessinée à grands coups d’archives.

Photo tirée du journal La Presse du lundi 9 novembre 2009, page A5. Détail de l’encart publicitaire retenu par TV5.

Retrouvez ci-dessous les 31ème épisode de Fullmetal Alchemist: Brotherhood.

Sources : Dybex@Dailymotion – Random Curiosity