Comment on "The Jones-Hore theory of radical-ion-pair reactions is not self-consistent" (arXiv:1010.3888v3)

A short comment on "The Jones-Hore theory of radical-ion-pair reactions is not self-consistent" (arXiv:1010.3888v3) is presented. In the comment, it is pointed out that the paper includes a misconception about the Jones-Hore approach in Chem. Phys. Lett. 488 (2010) 90-93. The re-formulation is presented and it is demonstrated that the Jones-Hore theory is consistent at least on the point claimed by I. K. Kominis in the paper

Reaction operators for spin-selective chemical reactions of radical pairs

Spin-selective reactions of radical pairs have traditionally been modelled theoretically by adding phenomenological rate equations to the quantum mechanical equation of motion of the radical pair spin density matrix. More recently an alternative set of rate expressions, based on a quantum measurement approach, has been suggested. Here we show how these two reaction operators can be seen as limiting cases of a more general reaction scheme.Comment: 10 pages, pdf from MS Word. Chem. Phys. Lett. (in press

Bird Cryptochrome 1a Is Excited by Blue Light and Forms Long-Lived Radical- Pairs

Cryptochromes (Cry) have been suggested to form the basis of light-dependent magnetic compass orientation in birds. However, to function as magnetic compass sensors, the cryptochromes of migratory birds must possess a number of key biophysical characteristics. Most importantly, absorption of blue light must produce radical pairs with lifetimes longer than about a microsecond. Cryptochrome 1a (gwCry1a) and the photolyase-homology-region of Cry1 (gwCry1-PHR) from the migratory garden warbler were recombinantly expressed and purified from a baculovirus/Sf9 cell expression system. Transient absorption measurements show that these flavoproteins are indeed excited by light in the blue spectral range leading to the formation of radicals with millisecond lifetimes. These biophysical characteristics suggest that gwCry1a is ideally suited as a primary light-mediated, radical-pair-based magnetic compass recepto

Chemical Magnetoreception: Bird Cryptochrome 1a Is Excited by Blue Light and Forms Long-Lived Radical-Pairs

Cryptochromes (Cry) have been suggested to form the basis of light-dependent magnetic compass orientation in birds. However, to function as magnetic compass sensors, the cryptochromes of migratory birds must possess a number of key biophysical characteristics. Most importantly, absorption of blue light must produce radical pairs with lifetimes longer than about a microsecond. Cryptochrome 1a (gwCry1a) and the photolyase-homology-region of Cry1 (gwCry1-PHR) from the migratory garden warbler were recombinantly expressed and purified from a baculovirus/Sf9 cell expression system. Transient absorption measurements show that these flavoproteins are indeed excited by light in the blue spectral range leading to the formation of radicals with millisecond lifetimes. These biophysical characteristics suggest that gwCry1a is ideally suited as a primary light-mediated, radical-pair-based magnetic compass receptor

Strategies for Detection and Monitoring of CO2 Leakage in Sub-seabed CCS

AbstractCarbon dioxide (CO2) capture and storage (CCS) in sub-seabed geological formations is currently being studied as a potential option to mitigate the accumulation of anthropogenic CO2 in the atmosphere. For the verification of CO2 storage integrity in the sub-seafloor, developments of the techniques to detect and monitor CO2 leaked from the seafloor is vital. Seafloor-based acoustic tomography is a technique that can be used to detect emissions of liquid CO2 droplets or gas CO2 bubbles from the seafloor. An in-situ pH/pCO2 sensor can provide rapid and high-precision measurements in seawater, and is therefore able to detect pH and pCO2 changes caused by the leaked CO2. An autonomous underwater vehicle (AUV) installed with the pH/pCO2 sensor provides an automated observation technology that can detect and monitor CO2 leakage from the seafloor. By towing a multi-layer monitoring system consisting of a number of pH/pCO2 sensors and transponders, the dispersed area of leaked CO2 overlying a CCS site can also be identified. The seafloor-mounted automatic elevator consists of a buoy equipped with pH/pCO2 and depth sensors, collecting intermittently a CTD-like data as it ascends and descends. Hence, CO2 leakage from the seafloor is detected and monitored as follows. Step 1: detect the CO2 leakage by the seafloor-based acoustic tomography. Step 2: map the distribution of the leakage points using the pH/pCO2 sensor installed on the AUV. Step 3: monitor the impacted area using a remotely operated underwater vehicle or the automatic elevator or by towing the multi-layer monitoring system