Obsidian hydration profile measurements using a nuclear reaction technique

Ambient water diffuses into the exposed surfaces of obsidian, forming a hydration layer which increases in thickness with time to a maximum depth of 20-40 μm (ref. 1), this layer being the basic foundation of obsidian dating. We have used the resonance at a ^(19)F energy of 16.45 MeV (0.83 MeV centre-of-mass energy) (ref. 4) in the nuclear reaction ^1H(^(19)F,ɑy)^(16)O to measure directly the hydration profiles of obsidian samples. This technique has already been used to measure the hydrogen concentration profiles in lunar samples and other solids to depths up to 0.4 μm with a resolution of 0.02 μm (refs 5 and 6). A second strong resonance at 17.64 MeV is encountered in extending these measurements to greater depths but its contribution can be unfolded from the data

Peripheral T-cell lymphoma with t(6;14)(p25;q11.2) translocation presenting with massive splenomegaly.

Recurrent chromosomal translocations associated to peripheral T-cell lymphomas (PTCL) are rare. Here, we report a case of PTCL, not otherwise specified (NOS) with the karyotype 46,Y,add(X)(p22),t(6;14)(p25;q11) and FISH-proved breakpoints in the IRF4 and TCRAD loci, leading to juxtaposition of both genes. A 64-year-old male patient presented with mild cytopenias and massive splenomegaly. Splenectomy showed diffuse red pulp involvement by a pleomorphic medium- to large-cell T-cell lymphoma with a CD2+ CD3+ CD5− CD7− CD4+ CD8+/− CD30− TCRbeta-F1+ immunophenotype, an activated cytotoxic profile, and strong MUM1 expression. The clinical course was marked by disease progression in the bone marrow under treatment and death at 4 months. In contrast with two t(6;14)(p25;q11.2)-positive lymphomas previously reported to be cytotoxic PTCL, NOS with bone marrow and skin involvement, this case was manifested by massive splenomegaly, expanding the clinical spectrum of PTCLs harboring t(6;14)(p25;q11.2) and supporting consideration of this translocation as a marker of biological aggressiveness

Cryptomare magmatism 4.35 Gyr ago recorded in lunar meteorite Kalahari 009

The origin and evolution of the Moon remain controversial 1,2, with one of the most important questions for lunar evolution being the timing and duration of basaltic (mare) magmatism1,3–8. Here we report the result of ion microprobe U–Pb dating of phosphates in a lunar meteorite, Kalahari 009, which is classified as a very-low-Ti mare-basalt breccia. In situ analyses of five phosphate grains, associated with basaltic clasts, give an age of 4.3560.15 billion years. These ancient phosphate ages are thought to represent the crystallization ages of parental basalt magma, making Kalahari 009 one of the oldest known mare basalts. We suggest that mare basalt volcanism on the Moon started as early as 4.35 Gyr ago, relatively soon after its formation and differentiation, and preceding the bulk of lunar volcanism which ensued after the late heavy bombardment around 3.8-3.9 Gyr (refs 7 and 8). Considering the extremely low abundances of incompatible elements such as thorium and the rare earth elements in Kalahari 009 (ref. 9) and recent remote-sensing observations illustrating that the cryptomaria tend to be of very-low-Ti basalt type10–12, we conclude that Kalahari 009 is our first sample of a very-low-Ti cryptomare from the Moon