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An accurate knowledge of cage occupancy of methane is central for understanding the physical-chemical properties of gas hydrates, the actual inventory of natural gas in hydrate deposits and the description of gas exchange processes. Here we report the absolute cage occupancies, the cage occupancy ratios and hydration numbers of the synthetic CH4-H2O and CH4-D2O hydrates formed from the ice-gas system under different pressures and temperatures. The results were obtained from Rietveld refinement using high-resolution synchrotron X-ray powder diffraction patterns and from Raman spectroscopic measurements. The small-cage occupancies of methane in the deuterated hydrates are found to be slightly higher than in the hydrogenated form, likely due to their different lattice constants. The CH4 occupancy in the small cages agrees fairly well with the predictions of CSMGem at the formation pressure of 3.5 MPa, but with the increasing formation pressure the disagreement grows up to 11 percent. While some deficiency of the prediction model cannot be excluded, the observed discrepancy may well be due to experimental difficulties of reaching true equilibrium at higher pressures. The experimentally determined large-to-small cage occupancy ratios of the synthetic and natural CH4 hydrates formed from the water-gas system are consistently higher than the results of CSMGem calculations. Possible reasons for these discrepancies will be discussed., Comment: Unpublished contribution to the 8th International Conference on Gas Hydrates (ICGH-8), Beijing, China, 28 July - 1 August 2015 (was only available to the conference participants)

Synchrotron powder diffraction data were measured on various gas hydrates prepared at different fugacities and recovered to low temperatures. The data extend to sin {\theta}/{\lambda} values of at least 1.01 {\AA}-1, in some cases up to 1.48 {\AA}-1, i.e. at least 3 times further in reciprocal space than the best single crystal data obtained so far. Here the results of CO2-hydrate are presented in detail. Structural information is obtained from Rietveld refinements to unprecedented precision. All H-bonded O-O distances are found to be close to 2.75-2.76 {\AA}, i.e. very close to the values in ice Ih; differences between a hydrogenated and deuterated host lattice are insignificant. Cage occupancies were obtained for the first time in free refinements together with positional parameters of the guest molecule and their atomic displacement parameters. There is good agreement between the experimental cage occupancies and prediction results from CSMGem., Comment: Unpublished contribution to the 7th International Conference on Gas Hydrates (ICGH-7), Edinburgh, UK, 17-21 July 2011 (was only available to the conference participants)

How does the human brain represent simple compositions of constituents: actors, verbs, objects, directions, and locations? Subjects viewed videos during neuroimaging (fMRI) sessions from which sentential descriptions of those videos were identified by decoding the brain representations based only on their fMRI activation patterns. Constituents (e.g., "fold" and "shirt") were independently decoded from a single presentation. Independent constituent classification was then compared to joint classification of aggregate concepts (e.g., "fold-shirt"); results were similar as measured by accuracy and correlation. The brain regions used for independent constituent classification are largely disjoint and largely cover those used for joint classification. This allows recovery of sentential descriptions of stimulus videos by composing the results of the independent constituent classifiers. Furthermore, classifiers trained on the words one set of subjects think of when watching a video can recognise sentences a different subject thinks of when watching a different video., Comment: 28 pages; 8 figures; 8 tables

How does the human brain represent simple compositions of objects, actors,and actions? We had subjects view action sequence videos during neuroimaging (fMRI) sessions and identified lexical descriptions of those videos by decoding (SVM) the brain representations based only on their fMRI activation patterns. As a precursor to this result, we had demonstrated that we could reliably and with high probability decode action labels corresponding to one of six action videos (dig, walk, etc.), again while subjects viewed the action sequence during scanning (fMRI). This result was replicated at two different brain imaging sites with common protocols but different subjects, showing common brain areas, including areas known for episodic memory (PHG, MTL, high level visual pathways, etc.,i.e. the 'what' and 'where' systems, and TPJ, i.e. 'theory of mind'). Given these results, we were also able to successfully show a key aspect of language compositionality based on simultaneous decoding of object class and actor identity. Finally, combining these novel steps in 'brain reading' allowed us to accurately estimate brain representations supporting compositional decoding of a complex event composed of an actor, a verb, a direction, and an object., Comment: 11 pages, 6 figures