Reversibly locking a protein fold in an active conformation with a disulfide bond: Integrin αL I domains with high affinity and antagonist activity in vivo

The integrin αLβ2 has three different domains in its headpiece that have been suggested to either bind ligand or to regulate ligand binding. One of these, the inserted or I domain, has a fold similar to that of small G proteins. The I domain of the αM and α2 subunits has been crystallized in both open and closed conformations; however, the αL I domain has been crystallized in only the closed conformation. We hypothesized that the αL domain also would have an open conformation, and that this would be the ligand binding conformation. Therefore, we introduced pairs of cysteine residues to form disulfides that would lock the αL I domain in either the open or closed conformation. Locking the I domain open resulted in a 9,000-fold increase in affinity to intercellular adhesion molecule-1 (ICAM-1), which was reversed by disulfide reduction. By contrast, the affinity of the locked closed conformer was similar to wild type. Binding completely depended on Mg2+. Orders of affinity were ICAM-1 > ICAM-2 > ICAM-3. The kon, koff, and KD values for the locked open I domain were within 1.5-fold of values previously determined for the αLβ2 complex, showing that the I domain is sufficient for full affinity binding to ICAM-1. The locked open I domain antagonized αLβ2-dependent adhesion in vitro, lymphocyte homing in vivo, and firm adhesion but not rolling on high endothelial venules. The ability to reversibly lock a protein fold in an active conformation with dramatically increased affinity opens vistas in therapeutics and proteomics.

Collective effects in light scattering from cold strontium clouds

A cold atomic cloud is a versatile object, because it offers many handles to control and tune its properties. This facilitates studies of its behavior in various circumstances, such as sample temperature, size and density, composition, dimensionality and coherence time. The range of possible experiments is constrained by the specifications of the atomic species used. In this thesis presents the work done in the experiment for laser cooling of strontium atoms, focusing on its stability, which should provide cold and ultracold samples for the study of collective effects in light scattering. From the initial apparatus, innumerous changes were performed. The vacuum system got improved and now reached lower ultra high vacuum due to the pre-baking done to its parts and adding a titanium-sublimation stage. The quadrupole trap were improved by the design and construction of a new pair of coils. The stability of the blue, green and red laser systems and the loss prevention of laser light were improved, giving rise to a robust apparatus. Another important point is the development of homemade devices to reduce the costs and to be used as a monitor of different parts of an cold atoms experiment. From this homemade devices, we could demonstrate a dramatic linewidth narrowing by injection lock of an low cost 461 nm diode laser and its application to our strontium experiment. In the end, this improved experimental apparatus made possible the study of a new scattering effect, the mirror assisted coherent back-scattering (mCBS).

Russia goes on the offensive ahead of the Eastern Partnership summit in Vilnius. OSW Commentary No. 115, 30.09.2013

In recent weeks, Russia has stepped up its efforts to prevent a group of former Soviet republics from tightening their relations with the European Union. The intensification of these efforts comes ahead of the upcoming Eastern Partnership summit, scheduled to take place in Vilnius on 28-29 November. It is expected that during the summit Kiev will sign the EU-Ukraine Association Agreement (AA) initialled in March 2012, including an agreement for a Deep and Comprehensive Free Trade Area (DCFTA). Meanwhile, Moldova, Armenia and Georgia are expected to initial similar documents, effectively accepting their terms and conditions, and paving the way for their official signing in the near future. Moscow has always viewed the relations between the EU and the post-Soviet states as a threat to its own influence in the region. Consequently, any attempts to tighten these relations have been actively opposed by Russia. The EU’s Eastern Partnership programme, launched in 2009, has posed a particular challenge to Moscow’s policies in the region.. Russia responded by rolling out a Eurasian integration project, which began in 2010 with the establishment of the Customs Union of Russia, Kazakhstan and Belarus, and is expected to culminate in the establishment of the Eurasian Economic Union by 2015. Moscow’s overarching objective has been to persuade the countries in the region, especially Ukraine, to adopt an unambiguously pro-Russian geopolitical stance and to join the integration project proposed by the Kremlin. The Russian government hopes that this would permanently place these states in Moscow’s sphere of influence and at the same time prevent them from developing closer relations with Brussels. Russia has regularly taken actions aimed at showcasing the benefits of integration with the Customs Union (particularly, by promising preferential pricing of Russian energy resources) and at the same time it has adopted measures highlighting the pitfalls of retaining a pro-European orientation (mainly by imposing occasional trade sanctions). The upcoming summit in Vilnius, during which Ukraine, Moldova, Armenia and Georgia could lock themselves on to a pro-European course, has spurred Moscow to intensify its efforts to torpedo a successful outcome of the Vilnius meeting, with a view to slowing down or even blocking the possibility of closer cooperation between the EU and the former Soviet republics.

Olmsted Lock Outlet, Ohio River : hydraulic model investigation /

Cover title.

Establishment of a National Accident Sampling System (NASS) team in Ashley, Chicot, Desha, Drew, and Lincoln Counties, Arkansas. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Lock design, sidewall port filling and emptying system : final report /

"Ju;y 1975."

Development of a low cost anti-lock brake system for small motorcycles. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Towards a low cost highly reliable anti-lock brake system for small motorcycles. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Project report on modernization of the lock and spillway at John Hollis Bankhead Dam, Black Warrior Reiver, Alabama.

Cover title.

Laboratory tests of hydraulic model of filling and emptying system for the MacArthur Lock, St. Marys River, Sault Ste. Marie, Michigan; final report.

Mode of access: Internet.

Laboratory tests on hydraulic models of a submergible tainter lock gate for St. Anthony Falls lower lock, Mississippi River, Minneapolis, Minn.; final report.

Mode of access: Internet.

Laboratory tests on models of lock hydraulic systems; final report.

Mode of access: Internet.

Construction of Lock no. 2, Monongahela River.

Mode of access: Internet.

The history of England in verse /

Mode of access: Internet.

Illustrated guide to, and popular history of Leamington & Warwick : with excursions to Kenilworth, Stratford-on-Avon, and other places in the neighbourhood.

Mode of access: Internet.