http://bio-ice.forumotion.com/feed/? Latest topics Tue, 24 Nov 2009 11:07:03 GMT 10 http://i71.servimg.com/u/f71/13/31/11/69/banner12.jpg http://bio-ice.forumotion.com/feed/? http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/sugar-and-ice-evaluating-the-interactions-between-heterogeneous-ice-nucleators-and-solutes-t20.htm ceMorris In our attempt to understand the mechanisms by which ice nucleators catalyze freezing, we biologists have sometimes imagined ice nucleation active proteins as having an attractive force that draws water molecules into the appropriate configuration to form ice. Our simplified model involves water molecules and proteins. But what would happen to the interaction of water molecules and these proteins in the presence of other forces on the water molecules? The forces that can bind water molecules ... Physics of heterogeneous ice nucleation Tue, 24 Nov 2009 11:07:03 GMT http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/sugar-and-ice-evaluating-the-interactions-between-heterogeneous-ice-nucleators-and-solutes-t20.htm#26 http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/sugar-and-ice-evaluating-the-interactions-between-heterogeneous-ice-nucleators-and-solutes-t20.htm http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/what-really-is-the-hallett-mossop-process-t19.htm Tom Hill If bioaerosols play any significant role in initiating rainfall it must be by triggering the Hallett-Mossop process of ice multiplication. But testing this link is difficult because there still seems to be much uncertainty about what the mechanism actually is, what triggers it and how prevalent it is. In temperate climates rain is initiated by ice nucleation (in thunderstorms it is a mix of this and droplet coalescence). But ice nuclei are rare. Typically there are 0.1-20/L active at -15°C ... Behavior of ice nucleators in the clouds Mon, 16 Nov 2009 10:17:58 GMT http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/what-really-is-the-hallett-mossop-process-t19.htm#25 http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/what-really-is-the-hallett-mossop-process-t19.htm http://bio-ice.forumotion.com/what-is-the-purpose-of-this-discussion-forum-f8/background-info-t1.htm Admin In the absence of catalysts for freezing, water can remain in a metastable liquid state at temperatures well below 0°C. Water in the liquid state at temperatures below 0°C is referred to as supercooled water. Spontaneous freezing of supercooled water occurs below –39°C. Hence, freezing catalysts are clearly essential for many natural freezing processes. A wide range of substances are able to catalyze ice nucleation. Various inorganic crystalline solids (the most well known of which ... What is the purpose of this discussion forum? Sat, 29 Nov 2008 21:56:00 GMT http://bio-ice.forumotion.com/what-is-the-purpose-of-this-discussion-forum-f8/background-info-t1.htm#1 http://bio-ice.forumotion.com/what-is-the-purpose-of-this-discussion-forum-f8/background-info-t1.htm http://bio-ice.forumotion.com/meeting-announcements-f6/prague-conference-t18.htm vali The sessions on Biological Aerosols will take place on Thursday, August 13,2009. Started with a talk by Anne-Marie Delort during the morning's Plenary Session, there will be 16 more papers presented during three sessions the rest of the day. Posters on the topic are included in the session scheduled for Tuesday afternoon. Of course, there are quite a number of other sessions during the week with papers relevant to biological aerosols and nucleation. The full program can ... Meeting announcements Sat, 20 Jun 2009 16:16:46 GMT http://bio-ice.forumotion.com/meeting-announcements-f6/prague-conference-t18.htm#23 http://bio-ice.forumotion.com/meeting-announcements-f6/prague-conference-t18.htm http://bio-ice.forumotion.com/resources-f5/snowflakes-and-snow-crystals-an-online-guide-t17.htm Admin
http://www.its.caltech.edu/~atomic/snowcrystals/]]> Resources Wed, 03 Jun 2009 19:32:58 GMT http://bio-ice.forumotion.com/resources-f5/snowflakes-and-snow-crystals-an-online-guide-t17.htm#22 http://bio-ice.forumotion.com/resources-f5/snowflakes-and-snow-crystals-an-online-guide-t17.htm http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/biological-ice-nucleation-is-there-added-value-of-biology-over-inert-chemistry-t16.htm ceMorris The recent publication of Mortazavi et al (2008) made me wonder if we need to be more precise about the meaning of « biological ice nucleation ». This paper points out that a wide range of environmental bacteria can induce freezing of supercooled water above the homogeneous nucleation point of pure water (-39°C). Their work focused on bacteria isolated from snow, and included ubiquitous organisms such as Stenotrophomonas maltophilia, Bacillus spp., and Microbacterium spp. that are also present ... Biology of microbial ice nucleators Thu, 21 May 2009 18:53:55 GMT http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/biological-ice-nucleation-is-there-added-value-of-biology-over-inert-chemistry-t16.htm#20 http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/biological-ice-nucleation-is-there-added-value-of-biology-over-inert-chemistry-t16.htm http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/freezing-induced-by-pseudomonas-syringae-see-a-filmed-demo-t15.htm ceMorris Here is a film we made in the lab to illustrate freezing induced by adding a drop of a suspension of Pseudomonas syringae to water supercooled to -6°C. Please comment on how we could improve the film (note that the You Tube version blurred the text on the initial info panels). Cindy Morris / INRA-Avignon, France / 8 May 2009 Detection and quantification of ice nucleators in the environment Fri, 08 May 2009 12:36:09 GMT http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/freezing-induced-by-pseudomonas-syringae-see-a-filmed-demo-t15.htm#19 http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/freezing-induced-by-pseudomonas-syringae-see-a-filmed-demo-t15.htm http://bio-ice.forumotion.com/resources-f5/refs-biological-particles-in-the-atmosphere-traits-and-abundance-t3.htm ceMorris Proxies for material of biological origin in the atmosphere: - levoglucosan (Puxbaum, Tenze-Kunit 2003; Puxbaum et al. 2007) - cellulose (Sanchez-Ochoa et al. 2007) - proteins (Jaenicke 2005) - DNA (Després et al. 2007) - manitol (Elbert et al. 2007) - heat and lysozyme sensitivity of ice nucleation activity (Christner et al. 2008) Review article on characterization of biological particles in the atmosphere (Georgakopoulos et al. 2008) REFERENCES Christner, B. C., ... Resources Sun, 30 Nov 2008 18:34:52 GMT http://bio-ice.forumotion.com/resources-f5/refs-biological-particles-in-the-atmosphere-traits-and-abundance-t3.htm#3 http://bio-ice.forumotion.com/resources-f5/refs-biological-particles-in-the-atmosphere-traits-and-abundance-t3.htm http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/in-ccn-and-cloud-seeding-t14.htm hpuxbaum We had contact with a company involved in cloud seeding to avoid hail-storms. An airplane equipped with a burner emitting silver-iodide nuclei was flying under cloud base. By updrafts the silver iodide is injected into higher elevations where ice particls form on the nuclei. The growing ice crystals then fall through the cloud layers with supercooled droplets. Those droplets then attach to the ice crytals by impaction freezing forming snow flakes and graupel which melts when falling through the ... Behavior of ice nucleators in the clouds Sun, 15 Feb 2009 12:36:57 GMT http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/in-ccn-and-cloud-seeding-t14.htm#17 http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/in-ccn-and-cloud-seeding-t14.htm http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/immersion-freezing-test-for-quantification-of-ice-nuclei-t11.htm ceMorris At a recent training course on characterization of bacterial ice nuleators held in Avignon, France (end of 2008 and early 2009), this is the protocol we taught for quantifying ice nucleation activity of bacterial strains. This technique is the basis of the technique used for detection of biological ice nucleators in environmental samples (Christner et al 2008 Science 319:1214 and Proc. Nat. Acad. Sci. 105: 18854–18859 ). How to determine the number of bacterial cells needed to produce ... Detection and quantification of ice nucleators in the environment Sun, 18 Jan 2009 22:36:38 GMT http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/immersion-freezing-test-for-quantification-of-ice-nuclei-t11.htm#13 http://bio-ice.forumotion.com/detection-and-quantification-of-ice-nucleators-in-the-environment-f2/immersion-freezing-test-for-quantification-of-ice-nuclei-t11.htm http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/next-generation-sequencing-for-metagenomics-of-cloud-dwelling-bacteria-t13.htm Suzanne Is anyone using next generation sequencing for looking at the collection of bacteria in clouds?
Why would the fluorescent pseudomonas be the predominant species in clouds?

Best,
Suzanne]]> Biology of microbial ice nucleators Mon, 19 Jan 2009 20:39:20 GMT http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/next-generation-sequencing-for-metagenomics-of-cloud-dwelling-bacteria-t13.htm#15 http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/next-generation-sequencing-for-metagenomics-of-cloud-dwelling-bacteria-t13.htm http://bio-ice.forumotion.com/other-topics-concerning-biological-ice-nucleation-f4/to-make-a-droplet-of-cloud-water-t12.htm ceMorris Ice formation is one of several steps in the making of precipitation. Formation of water droplets is also critical. Like ice formation, the transition of water vapor to the liquid phase (condensation) can be mediated by catalysts. These catalysts are called "Cloud Condensation Nuclei" (CCN). Although the properties of CCN are rather different from those of ice nuclei (IN) (CCN are often soluble materials whereas IN are insoluble), micro-organisms can be CCN as well as IN. The ... Other topics concerning biological ice nucleation Mon, 19 Jan 2009 13:22:25 GMT http://bio-ice.forumotion.com/other-topics-concerning-biological-ice-nucleation-f4/to-make-a-droplet-of-cloud-water-t12.htm#14 http://bio-ice.forumotion.com/other-topics-concerning-biological-ice-nucleation-f4/to-make-a-droplet-of-cloud-water-t12.htm http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/link-to-a-blog-post-on-meteorological-alchemy-t10.htm ceMorris I am posting this information to try to kick-start discussion here about serious topics, this present one being mostly outrageous and creative dreams. I suggest that you read the article posted on 24 Jan 2006 on the blog "Pruned" entitled "Meteorological Alchemy". Read about cloud farms, etc. It's worth visiting for the incredible pictures of saucer-shaped clouds trapped on mountain tops. http://pruned.blogspot.com/2006_01_01_archive.html Cindy Morris 23 ... Behavior of ice nucleators in the clouds Tue, 23 Dec 2008 13:19:32 GMT http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/link-to-a-blog-post-on-meteorological-alchemy-t10.htm#12 http://bio-ice.forumotion.com/behavior-of-ice-nucleators-in-the-clouds-f1/link-to-a-blog-post-on-meteorological-alchemy-t10.htm http://bio-ice.forumotion.com/meeting-announcements-f6/2009-aug-international-conference-on-nucleation-and-atmospheric-aerosols-t9.htm Admin International Conference on Nucleation and Atmospheric Aerosols. 10-14 Aug 2009, Prague http://www.icnaa.cz/Default.aspx Program outline: -Nucleation Theory and Experiment -Tropospheric and Stratospheric Aerosols -Cloud Drop and Ice Nucleation -Aerosol Climate Interactions -Biological Aerosols and their Nucleating Activity Paper (extended abstract) submission: 31 Jan 2009 Meeting announcements Mon, 15 Dec 2008 09:37:58 GMT http://bio-ice.forumotion.com/meeting-announcements-f6/2009-aug-international-conference-on-nucleation-and-atmospheric-aerosols-t9.htm#11 http://bio-ice.forumotion.com/meeting-announcements-f6/2009-aug-international-conference-on-nucleation-and-atmospheric-aerosols-t9.htm http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/role-and-evolution-of-the-in-gene-t6.htm Tom Hill I find it intriguing that it’s hard to define the principal ecological function of such a highly evolved protein. Could it actually have multiple functions or do we lack insight? Hirano and Upper (2000) wrote “there is no clear selection for destroying the leaf habitat. For most organisms, habitat destruction is regarded as highly unfavorable…..the bacteria reward themselves for success [as colonists] by destroying their habitat! Is this not paradoxical?” But could IN bacteria be ... Biology of microbial ice nucleators Fri, 05 Dec 2008 05:43:57 GMT http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/role-and-evolution-of-the-in-gene-t6.htm#7 http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/role-and-evolution-of-the-in-gene-t6.htm http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/heterogeneous-ice-nucleation-and-bio-particles-quick-summary-t8.htm vaughanp So as to "kick off" the discussion here, I'll just summarise a few of the emails exchanged about ice nucleation so far. Bruce Moffett asked about the Bergeron-Findeisen process in mixed-pahse clouds. Zev Levin explained that it involves air that has both liquid and ice present tending to have a humidity close to water saturation, so that there is great supersaturation with respect to ice. The latter causes rapid growth of ice crystals by diffusion of vapour, and any subsaturation ... Physics of heterogeneous ice nucleation Sun, 07 Dec 2008 00:33:30 GMT http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/heterogeneous-ice-nucleation-and-bio-particles-quick-summary-t8.htm#9 http://bio-ice.forumotion.com/physics-of-heterogeneous-ice-nucleation-f3/heterogeneous-ice-nucleation-and-bio-particles-quick-summary-t8.htm http://bio-ice.forumotion.com/meeting-announcements-f6/2009-july-dynamical-implications-of-aerosol-cloud-climate-interactions-t7.htm Admin Session M11 at the Joint IAMAS-IAPSO-IACS conference ("MOCA", www.moca-09.org), 19-29 July 2009, in Montreal, Canada.]]> Meeting announcements Fri, 05 Dec 2008 22:40:33 GMT http://bio-ice.forumotion.com/meeting-announcements-f6/2009-july-dynamical-implications-of-aerosol-cloud-climate-interactions-t7.htm#8 http://bio-ice.forumotion.com/meeting-announcements-f6/2009-july-dynamical-implications-of-aerosol-cloud-climate-interactions-t7.htm http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/ecology-of-biological-ice-nucleators-a-need-for-movement-t5.htm ceMorris We have recently wondered if ice nucleation activity of bacteria is part of a dissemination strategy, assuring that they will get transported back to the ground (via precipitation) once they have attained clouds. Posted today on Nature.com is an interesting article about a unifying framework for understanding the movement of organisms. Although animals are the likely target of thought, the framework is clearly applicable to ‘passive’ dissemination of air borne micro-organisms. See : http://www.nature.com/news/2008/081201/full/news.2008.1268.html Biology of microbial ice nucleators Wed, 03 Dec 2008 13:06:59 GMT http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/ecology-of-biological-ice-nucleators-a-need-for-movement-t5.htm#5 http://bio-ice.forumotion.com/biology-of-microbial-ice-nucleators-f7/ecology-of-biological-ice-nucleators-a-need-for-movement-t5.htm http://bio-ice.forumotion.com/resources-f5/refs-biological-ice-nucleators-t4.htm ceMorris -Bacteria as ice nucleators: (Kawahara et al. 1993; Kawahara et al. 1995; Kim et al. 1987; Lindow 1983; Maki et al. 1974; Maki and Willoughby 1978; Morris et al. 1992; Wallin et al. 1979; Watanabe and Arai 1986; Worland and Block 1999) -Fungi as ice nucleators: (free-living fungi and lichen symbionts) (Kieft 1988; Kieft and Ahmadjian 1989; Kieft, Ruscetti 1990; Pouleur et al. 1992; Richard et al. 1996) -Algae as ice nucleators: (Worland and Lukesova 2000) -INA in plant tissues ... Resources Sun, 30 Nov 2008 22:43:12 GMT http://bio-ice.forumotion.com/resources-f5/refs-biological-ice-nucleators-t4.htm#4 http://bio-ice.forumotion.com/resources-f5/refs-biological-ice-nucleators-t4.htm http://bio-ice.forumotion.com/resources-f5/remark-about-posting-references-t2.htm Admin
Firstly, if possible include the email address of an author so that users can obtain copies of the publications. Use the author contact address that is already cited in the publication where possible.

Post references by categories so that users of this site can find what they are looking for.

Any other ideas for optimal posting of references?]]> Resources Sun, 30 Nov 2008 16:57:46 GMT http://bio-ice.forumotion.com/resources-f5/remark-about-posting-references-t2.htm#2 http://bio-ice.forumotion.com/resources-f5/remark-about-posting-references-t2.htm