[ { "id": "authors:5t36h-mgd07", "collection": "authors", "collection_id": "5t36h-mgd07", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100719-111941340", "type": "article", "title": "Isothermal compression behavior of (Mg,Fe)O using neon as a pressure medium", "author": [ { "family_name": "Zhuravlev", "given_name": "Kirill K.", "clpid": "Zuravlev-K-K" }, { "family_name": "Jackson", "given_name": "J. M.", "orcid": "0000-0002-8256-6336", "clpid": "Jackson-J-M" }, { "family_name": "Wolf", "given_name": "A. S.", "clpid": "Wolf-A-S" }, { "family_name": "Wicks", "given_name": "J. K.", "clpid": "Wicks-J-K" }, { "family_name": "Yan", "given_name": "J.", "clpid": "Yan-J" }, { "family_name": "Clark", "given_name": "S. M.", "clpid": "Clark-S-M" } ], "abstract": "We present isothermal volume compression behavior of two polycrystalline (Mg,Fe)O samples with FeO = 39 and 78 mol% up to ~90 GPa at 300 K using synchrotron X-ray diffraction and neon as a pressure-transmitting medium. For the iron-rich (Mg_(0.22)Fe_(0.78))O sample, a structural transition from the B1 structure to a rhombohedral structure was observed at 41.6 GPa, with no further indication of changes in structural or compression behavior changes up to 93 GPa. In contrast, a change in the compression behavior of (Mg_(0.61)Fe_(0.39))O was observed during compression at P \u2265 71 GPa and is indicative of a spin crossover occurring in the Fe^(2+) component of (Mg_(0.61)Fe_(0.39))O. The low-spin state exhibited a volume collapse of ~3.5%, which is a larger value than what was observed for a similar composition in a laser-heated NaCl medium. Upon decompression, the volume of the high-spin state was recovered at approximately 65 GPa. We therefore bracket the spin crossover at 65 \u2264 P (GPa) \u2264 77 at 300 K (Mg_(0.61)Fe_(0.39))O. We observed no deviation from the B1 structure in (Mg_(0.61)Fe_(0.39))O throughout the pressure range investigated.", "doi": "10.1007/s00269-009-0347-6", "issn": "0342-1791", "publisher": "Springer", "publication": "Physics and Chemistry of Minerals", "publication_date": "2010-07", "series_number": "7", "volume": "37", "issue": "7", "pages": "465-474" }, { "id": "authors:w85m2-maw89", "collection": "authors", "collection_id": "w85m2-maw89", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:CLAdev95", "type": "article", "title": "CLAVATA3 is a specific regulator of shoot and floral meristem development affecting the same processes as CLAVATA1", "author": [ { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Running", "given_name": "Mark P.", "clpid": "Running-M-P" }, { "family_name": "Meyerowitz", "given_name": "Elliot M.", "orcid": "0000-0003-4798-5153", "clpid": "Meyerowitz-E-M" } ], "abstract": "We have previously described the phenotype of Arabidopsis thaliana plants with mutations at the CLAVATA1 (CLV1) locus (Clark, S. E., Running, M. P. and Meyerowitz, E. M. (1993) Development 119, 397-418). Our investigations demonstrated that clv1 plants develop enlarged vegetative and inflorescence apical meristems, and enlarged and indeterminate floral meristems. Here, we present an analysis of mutations at a separate locus, CLAVATA3(CLV3), that disrupt meristem development in a manner similar to clv1mutations. clv3 plants develop enlarged apical meristems as early as the mature embryo stage. clv3 floral meristems are also enlarged compared with wild type, and maintain a proliferating meristem throughout flower development. clv3 root meristems are unaffected, indicating that CLV3 is a specific regulator of shoot and floral meristem development. We demonstrate that the strong clv3-2 mutant is largely epistatic to clv1 mutants, and that the semi-dominance of clv1 alleles is enhanced by double heterozygosity with clv3 alleles, suggesting that these genes work in the same pathway to control meristem development. We propose that CLV1 and CLV3 are required to promote the differentiation of cells at the shoot and floral meristem.", "issn": "0950-1991", "publisher": "Company of Biologists", "publication": "Development", "publication_date": "1995-07", "series_number": "7", "volume": "121", "issue": "7", "pages": "2057-2067" }, { "id": "authors:cqyn0-m2116", "collection": "authors", "collection_id": "cqyn0-m2116", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:BASrsi93b", "type": "article", "title": "Digital signal processor control of scanned probe microscopes", "author": [ { "family_name": "Baselt", "given_name": "David R.", "clpid": "Baselt-D-R" }, { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Youngquist", "given_name": "Michael G.", "clpid": "Youngquist-M-G" }, { "family_name": "Spence", "given_name": "Charles F.", "clpid": "Spence-C-F" }, { "family_name": "Baldeschwieler", "given_name": "John D.", "clpid": "Baldeschwieler-J-D" } ], "abstract": "Digital signal processors have made it possible to control scanned probe microscopes using straightforward software emulations of analog circuits. Using a system consisting of a commercially available digital signal processor board interfaced to analog I/O, we have developed algorithms for self-optimizing feedback, raster generation (with hysteresis correction, sample tilt compensation, and scan rotation), lock-in detection, and automatic tip-sample approach. We also discuss an instruction parser that takes advantage of the digital architecture to allow automatic operation for extended periods.", "doi": "10.1063/1.1144462", "issn": "0034-6748", "publisher": "American Institute of Physics", "publication": "Review of Scientific Instruments", "publication_date": "1993-07", "series_number": "7", "volume": "64", "issue": "7", "pages": "1874-1882" }, { "id": "authors:ymhz4-eas27", "collection": "authors", "collection_id": "ymhz4-eas27", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:CLArsi93", "type": "article", "title": "A high performance scanning force microscope head design", "author": [ { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Baldeschwieler", "given_name": "John D.", "clpid": "Baldeschwieler-J-D" } ], "abstract": "A stable and highly sensitive scanning force microscope head design is presented. The head provides an implementation of the optical lever detection method in which mechanical vibration noise has been minimized.", "doi": "10.1063/1.1144141", "issn": "0034-6748", "publisher": "Review of Scientific Instruments", "publication": "Review of Scientific Instruments", "publication_date": "1993-04-01", "series_number": "4", "volume": "64", "issue": "4", "pages": "904-907" }, { "id": "authors:c1kmb-7fc73", "collection": "authors", "collection_id": "c1kmb-7fc73", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160309-075030821", "type": "article", "title": "Biological microscopy: the emergence of digital microscopy", "author": [ { "family_name": "Ivins", "given_name": "Jonathan K.", "clpid": "Ivins-J-K" }, { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Fraser", "given_name": "Scott E.", "orcid": "0000-0002-5377-0223", "clpid": "Fraser-S-E" } ], "abstract": "The past few years have seen a tremendous renaissance in biological optical microscopy, mainly as a result of the application of digital image processing and video imaging techniques. We review recent developments in microscopy that are permitting unprecedented views of biological structure and function.", "doi": "10.1016/0958-1669(93)90035-U", "issn": "0958-1669", "publisher": "Elsevier", "publication": "Current Opinion in Biotechnology", "publication_date": "1993-02", "series_number": "1", "volume": "4", "issue": "1", "pages": "69-74" }, { "id": "authors:hn3zc-k3b42", "collection": "authors", "collection_id": "hn3zc-k3b42", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:CLArsi92", "type": "article", "title": "Hardware for digitally controlled scanned probe microscopes", "author": [ { "family_name": "Clark", "given_name": "S. M.", "clpid": "Clark-S-M" }, { "family_name": "Baselt", "given_name": "D. R.", "clpid": "Baselt-D-R" }, { "family_name": "Spence", "given_name": "C. F.", "clpid": "Spence-C-F" }, { "family_name": "Youngquist", "given_name": "M. G.", "clpid": "Youngquist-M-G" }, { "family_name": "Baldeschwieler", "given_name": "J. D.", "clpid": "Baldeschwieler-J-D" } ], "abstract": "The design and implementation of a flexible and modular digital control and data acquisition system for scanned probe microscopes (SPMs) is presented. The measured performance of the system shows it to be capable of 14-bit data acquisition at a 100-kHz rate and a full 18-bit output resolution resulting in less than 0.02-\u00c5 rms position noise while maintaining a scan range in excess of 1 \u00b5m in both the X and Y dimensions. This level of performance achieves the goal of making the noise of the microscope control system an insignificant factor for most experiments. The adaptation of the system to various types of SPM experiments is discussed. Advances in audio electronics and digital signal processors have made the construction of such high performance systems possible at low cost.", "doi": "10.1063/1.1143728", "issn": "0034-6748", "publisher": "Review of Scientific Instruments", "publication": "Review of Scientific Instruments", "publication_date": "1992-10-01", "series_number": "10", "volume": "63", "issue": "10", "pages": "4296-4307" }, { "id": "authors:mbpra-dy840", "collection": "authors", "collection_id": "mbpra-dy840", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150107-150516043", "type": "article", "title": "A Novel Instrument for Separating Large DNA Molecules with Pulsed Homogeneous Electric Fields", "author": [ { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Lai", "given_name": "Eric", "clpid": "Lai-E" }, { "family_name": "Birren", "given_name": "Bruce W.", "clpid": "Birren-B-W" }, { "family_name": "Hood", "given_name": "Leroy", "orcid": "0000-0001-7158-3678", "clpid": "Hood-L-E" } ], "abstract": "A new instrument has been developed for the electrophoretic separation of large DNA molecules that can independently regulate the voltage of each of 24 electrodes and allow the magnitude, orientation, homogeneity, and duration of the electric field to be precisely controlled. Each parameter can be varied at any time during the electrophoretic process. Thus distinct sets of conditions can be combined to optimize the separation of various fragment sizes in a single run. Independent control of electrode voltage allows all of the fields to be generated with electrodes arranged in a closed contour, independent of a particular geometry. This device increases both the resolution in any size range and the speed of separation, especially for DNA molecules larger than 3 megabases.", "doi": "10.1126/science.3045968", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "1988-09-02", "series_number": "4870", "volume": "241", "issue": "4870", "pages": "1203-1205" }, { "id": "authors:g0g87-fgx07", "collection": "authors", "collection_id": "g0g87-fgx07", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120531-143038049", "type": "article", "title": "Optimized conditions for pulsed field gel electrophoretic separations of DNA", "author": [ { "family_name": "Birren", "given_name": "Bruce W.", "clpid": "Birren-B-W" }, { "family_name": "Lai", "given_name": "Eric", "clpid": "Lai-E" }, { "family_name": "Clark", "given_name": "Steven M.", "clpid": "Clark-S-M" }, { "family_name": "Hood", "given_name": "Leroy", "orcid": "0000-0001-7158-3678", "clpid": "Hood-L-E" }, { "family_name": "Simon", "given_name": "Melvin I.", "clpid": "Simon-M-I" } ], "abstract": "Quantitative measurement of DNA migration in gel electrophoresis requires precisely controlled homogeneous electric fields. A new electrophoresis system has allowed us to explore several parameters governing DNA migration during homogeneous field pulsed field gel (PFG) electrophoresis. Migration was measured at different switch times, temperatures, agarose concentrations, and voltage gradients. Conditions which increase DNA velocities permit separation over a wider size range, but reduce resolution. We have also varied the angle between the alternating electric fields. Reorientation angles between 105\u00b0 and 165\u00b0 give equivalent resolution, despite significant differences in DNA velocity. Separation of DNA fragments from 50 to greater than 7000 kilobases (Kb) can easily be optimized for speed and resolution based on conditions we describe.", "doi": "10.1093/nar/16.15.7563", "issn": "0305-1048", "publisher": "Nucleic Acids Research", "publication": "Nucleic Acids Research", "publication_date": "1988-08-11", "series_number": "15", "volume": "16", "issue": "15", "pages": "7563-7582" } ]