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The data from the Nobeyama Radio Observatory 45 m telescope Galactic Center CO survey have been analyzed to generate a compilation of molecular clouds with intense CO emission in this region. Clouds are identiÐed in an automated manner through the main part of the survey data for all CO emission peaks exceeding 10 K The measured parameters of identiÐed clouds are analyzed and (T R *). cross-correlated to compare with those of clouds in the Galactic disk. For the clouds in the Galactic center (GC), we Ðnd the scaling laws of the type and which are similar to88, those of clouds in the Galactic disk. All the GC clouds identiÐed have larger velocity widths and virial theorem masses each above the and lines of the disk clouds. We diagnosed gravitational p V -S L CO -M VT stabilities of identiÐed clouds assuming that the disk clouds are nearly at the onset of gravitational instability. All the clouds and cloud complexes in the GC are gravitationally stable, indicating they are in equilibrium with high pressure in the GC environment. Gravitationally less stable clouds follow the main ridge of intense CO emission, part of which deÐne two rigidly rotating molecular arms. The velocity dispersion of a cloud correlates inversely with the degree of gravitational instability. It is concluded that mechanisms such as orbit crowding at the inner Lindblad resonance may promote gravitational instability and subsequent star formation.

We present high-resolution CO images of the Galactic center region taken with the 2 ] 2 focal-plane array receiver mounted on the 45 m telescope of Nobeyama Radio Observatory. We have collected about 44,000 12C16O (J \ 1È0) spectra and over 13,000 13C16O (J \ 1È0) spectra with a 34A (1.4 pc) grid spacing. The 12CO mapping area is roughly and which covers.6, almost the full extent of the molecular gas concentration in the Galactic center. These CO images demonstrate extremely complex distribution and kinematics of molecular gas in the Galactic center. While its large-scale behavior can be attributed to the well-known coherent features, bright CO emission arises from a number of compact (d ¹ 10 pc) clouds with large velocity widths (*V º 30 km s~1 ). The small-scale structure of molecular gas is characterized by Ðlaments, arcs, and shells. The boisterous molecular gas kinematics there may be a result of violent release of kinetic energy by a number of supernova explosions and/or Wolf-Rayet stellar winds.

Polarized Raman spectra of oriented fibers of calf thymus DNA in the A and B conformations have been obtained by use of a Raman microscope operating in the 180 degrees back-scattering geometry. The following polarized Raman intensities in the spectral interval 200-1800 cm-1 were measured with both 514.5 and 488.0 nm laser excitations: (1) Icc, in which the incident and scattered light are polarized parallel to the DNA helical axis (c axis); (2) Ibb, in which the incident and scattered light are polarized perpendicular to c; and (3) Ibc and Icb, in which the incident and scattered light are polarized in mutually perpendicular directions. High degrees of structural homogeneity and unidirectional orientation were confirmed for both the A and B form fibers, as judged by comparison of the observed Raman markers and intensity anisotropies with measurements reported previously for oligonucleotide single crystals of known three-dimensional structures. The fiber Raman anisotropies have been combined with solution Raman depolarization ratios to evaluate the local tensors corresponding to key conformation-sensitive Raman bands of the DNA bases and sugar-phosphate backbone. The present study yields novel vibrational assignments for both A DNA and BDNA conformers and also confirms many previously proposed Raman vibrational assignments. Among the significant new findings are the demonstration of complex patterns of A form and B form indicator bands in the spectral intervals 750-900 and 1050-1100 cm-1, the identification of highly anisotropic tensors corresponding to vibrations of base, deoxyribose, and phosphate moieties, and the determination of relatively isotropic Raman tensors for the symmetrical stretching mode of phosphodioxy groups in A and B DNA. The present fiber results provide a basis for exploitation of polarized Raman spectroscopy to determine DNA helix orientation as well as to probe specific nucleotide residue orientations in nucleoproteins, viruses, and other complex biological assemblies.

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SAMPLES AND INSTRUMENTSNatural flax and ramie fibers, delignitied flax and ramie fibers, and amorphous cellulose prepared from cotton were used in the present experiments. These were all kindly supplied gan.In the infrared absorption measurements, principally a Perkin-Elmer 21 spectrometer was used with the NaCl optics. In order to obtain better resolution in the higher frequency region, sometimes CaFz prism mounted in the Perkin-Elmer 21 and more often LiF prism mounted in a Perkin-Elmer 112 spectrometer were used. For obtaining polarized radiation AgCl polarizers were used. RESULTS AND INTERPRETATIONS (1) Infrared Dichroism of Cellulose FiberThe natural flax and ramie fibers examined were about 10 p thick, too thick for observation in the 900-1100 cm.-' and 3100-3600 cm.-' regions. Delignifying and pressing made them a little thinner (to 5-7p) and made better observations possible, though they were still too thick. Figure 1A is typical of the results obtained with delignified and pressed fibers. sity, Hongo, Tokyo, Japan.

Duchenne muscular dystrophy (DMD) is an X-linked lethal muscle disorder caused by mutations in the Dmd gene encoding Dystrophin12. DMD model animals, such as mdx mice and canine X-linked muscular dystrophy dogs, have been widely utilized in the development of a treatment for DMD3. Here, we demonstrate the generation of Dmd-mutated rats using a clustered interspaced short palindromic repeats (CRISPR)/Cas system, an RNA-based genome engineering technique that is also adaptive to rats. We simultaneously targeted two exons in the rat Dmd gene, which resulted in the absence of Dystrophin expression in the F0 generation. Dmd-mutated rats exhibited a decline in muscle strength, and the emergence of degenerative/regenerative phenotypes in the skeletal muscle, heart, and diaphragm. These mutations were heritable by the next generation, and F1 male rats exhibited similar phenotypes in their skeletal muscles. These model rats should prove to be useful for developing therapeutic methods to treat DMD.