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The recombination-activating genes (RAGs) and the DNA cross-link repair 1C gene (DCLRE1C) encode the enzymes RAG1, RAG2 and Artemis. They are critical components of the V(D)J recombination machinery. V(D)J recombination is well known as a prerequisite for the development and antigen diversity of T and B cells. New findings suggested that RAG deficiency impacts the cellular fitness and function of murine NK cells. It is not known whether NK cells from severe combined immunodeficiency (SCID) patients with defective RAGs or DCLRE1C (RAGs&minus, /DCLRE1C&minus, NK) are active against virus infections. Here, we evaluated the anti-HCMV activity of RAGs&minus, NK cells. NK cells from six SCID patients were functional in inhibiting HCMV transmission between cells in vitro. We also investigated the expansion of HCMV-induced NK cell subset in the RAG- or DCLRE1C-deficient patients. A dynamic expansion of NKG2C+ NK cells in one RAG-2-deficient patient was observed post HCMV acute infection. Our study firstly reveals the antiviral activity of human RAGs&minus, / DCLRE1C&minus, NK cells.

Raman spectroscopy was used to characterize and differentiate the two minerals calcite and dolomite and the bands related to the mineral structure. The (CO 3 ) 2− group is characterized by four prominent Raman vibrational modes: (a) the symmetric stretching, (b) the asymmetric deformation, (c) asymmetric stretching and (d) symmetric deformation. These vibrational modes of the calcite and dolomite were observed at 1440, 1088, 715 and 278 cm −1 . The significant differences between the minerals calcite and dolomite are observed by Raman spectroscopy. Calcite shows the typical bands observed at 1361, 1047, 715 and 157 cm −1 , and the special bands at 1393, 1098, 1069, 1019, 299, 258 and 176 cm −1 for dolomite are observed. The difference is explained on the basis of the structure variation of the two minerals. Calcite has a trigonal structure with two molecules per unit cell, and dolomite has a hexagonal structure. This is more likely to cause the splitting and distorting of the carbonate groups. Another cause for the difference is the cation substituting for Mg in the dolomite mineral.

Infrared transmission and emission spectroscopy were used to analyze the difference in structure and thermal behavior of two Chinese palygorskites. The position of the main bands identified in the infrared spectra of the palygorskites studied is similar for these two Chinese samples, but there are some differences in their intensity, which is significant. This discrepancy is attributed to the existence of impurities and the geological environments in different regions. The infrared emission spectra clearly show the structural changes and dehydroxylation of the palygorskites when the temperature is raised. The dehydration of the palygorskites is followed by the loss of intensity of the OH stretching vibration bands in the region of 3600-3200 cm(-1). Dehydroxylation is followed by the decrease in intensity in the bands between 3700 and 3550 cm(-1). Dehydration of pure palygorskite was completed by 600°C. Partial loss of coordinated water was observed at 400°C. Infrared emission spectroscopy is an effective method to determine the stability of the mineral.