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Notes: It is shown that the transition functions that give the global structure of the fiber bundle play an important role in the construction of the metric. The invariance properties of this metric under general gauge transformations are discussed and it is found that the usual requirement of a gauge-invariant metric leads to severe constraints on the gauge fields. To avoid them, it is shown that the metric should instead be covariant with respect to these transformations. Moreover the existence of global actions that are essential in the context of the consistency problem is also discussed. The presence of such actions is studied in both the principal and their associated bundles. In the case of a homogeneous bundle with G/H as the typical fiber, it is shown that a "spliced'' bundle with G×N(H)/H as the structure group has to be used. The unified space is then taken as the bundle space of its associated bundle.

Notes: High-grade exotic blocks in the Franciscan Complex at Jenner, California, show evidence for polydeformation/metamorphism, with eight distinct stages. Two parallel sets of mineral assemblages [(E) eclogite, and (BS) laminated blueschist] representing different bulk chemistry were identified. Stage 1, recorded by parallel aligned inclusions (S1) of crossite + omphacite + epidote + ilmenite + titanite + quartz (E), and glaucophane + actinolite + epidote + titanite (BS) in the central parts of zoned garnets, represents the epidote blueschist facies. The onset of a second stage (stage 2) is represented by a weak crenulation of S1 and growth of garnet. This stage develops a well-defined S2 foliation of orientated barroisite + epidote + titanite (E), or subcalcic actinolite + epidote + titanite (BS) at c. 90d̀ to S1, with syntectonic growth of garnet, defining the (albite-)epidote-amphibolite facies. A third stage, with aligned inclusions of glaucophane + (subcalcic) actinolite + phengite parallel to S2 in the outermost rims of large garnet grains, is assigned to the transitional (albite-)epidote-amphibolite/(garnet-bearing) epidote blueschist facies. The fourth stage represents the peak metamorphism, and was identified by unorientated matrix minerals in the least retrograded samples. In this stage the mineral assemblages garnet + omphacite + glaucophane + phengite (E) and garnet + winchite + phengite + epidote (BS) both represent the eclogite facies. Stage 5 is represented by the retrogression of eclogite facies assemblages to the epidote blueschist facies assemblages crossite/glaucophane + garnet + omphacite + epidote + phengite (E), and glaucophane + actinolite + epidote + phengite (BS), with the development of an S5 foliation subparallel to S2. Stage 6 represents a crenulation of S5, with the development of a well-defined S6 crenulation cleavage wrapping around relics of the eclogite facies assemblages. This crenulation cleavage is further weakly crenulated during a D7 event. Post-D7 (stage 8) is recorded by the growth of lawsonite + chlorite ± actinolite replacing garnet, and by veins of lawsonite + pumpellyite + aragonite and phengite + apatite. The different, yet coeval, mineral parageneses observed in rock types (E) and (BS) are probably due to differences in bulk chemistry.The metamorphic evolution from stage 1 to stage 8 seems to have been broadly continuous, following an anticlockwise P-Tpath: (1) epidote blueschist (garnet-free) to (2) (albite-)epidote-amphibolite to (3) transitional epidote blueschist (garnet-bearing)/(albite-)epidote-amphibolite to (4) eclogite to (5) epidote blueschist (garnet-bearing) to (6-7) epidote blueschist (garnet-free) facies to (8) lawsonite + pumpellyite + aragonite-bearing assemblages. This anticlockwise P-T path may have resulted from a decreasing geothermal gradient with time in the Mesozoic subduction zone of California at early or pre-Franciscan metamorphism.

Notes: We report a case of factitious panniculitis masquerading as florid pyoderma gangrenosum in a 35-year-old woman. At presentation, she had tender, ecchymotic plaques over the lower trunk and limbs, and several biopsies showed active lobular panniculitis. However, the extensive ulceration that ensued was clinically persuasive for pyoderma gangrenosum. We elected to treat the inflammatory element symptomatically with a range of topical and systemic medications including clobetasol propionate, tacrolimus 0.1% ointment, prednisolone, dapsone, cyclosporin A and mycophenolate mofetil, none of which effected an improvement. The possibility of a factitious aetiology had been suspected from the outset, and when signs of clinical depression emerged, antidepressant therapy was initiated and the ulcers were encased in fibreglass casts. Within a short period, healing commenced and slowly progressed with scar formation. In retrospect, we consider the diagnosis to have been factitious panniculitis on the basis of strong circumstantial evidence and the disparity between the histological and clinical features.

Notes: Congenital smooth muscle hamartoma (CSMH) with follicular spotted appearance is a rare clinical variant of CMSH in which patients have marked perifollicular papules in the patches. A linear distribution of CSMH is also extremely rare. We report a 16-year-old Korean girl with this uncommon form of CSMH who had linearly arranged, hyperpigmented lesions with follicular papules extending from the right flank to the right lower leg from birth. Pathological findings, including immunohistochemical stains, were consistent with smooth muscle hamartoma. To date, there are only four reports on this rare, follicular form and one report on the linear form of CSMH in the literature. This paper describes the first combined occurrence of follicular spotted lesions and linear arrangement in CSMH.

Notes: This letter describes a novel structure for very large scale integrated contact and interconnect technology that involves selective deposition of W on self-aligned TiN/TiSi2. The TiN layer serves to protect reaction between WF6 and TiSi2 and underlying Si during W deposition as well as to promote adhesion of W layer and minimize contact resistance. The selective deposition of W on TiN, very difficult with conventional hydrogen reduction process, is accomplished by employing a recently developed silane reduction process. The structure prevents silicon consumption leading to the encroachment commonly found in tungsten deposited directly on silicon in very shallow junctions. It is demonstrated that such a structure results in low contact resistance and junction leakages and is applicable to subhalf-micron devices. Tungsten with low resistivity of 8–9 μΩ cm can be achieved at room temperature with the resulting drop by a factor of 3–4 at liquid-nitrogen temperature making the structure more attractive for low-temperature application.

Notes: In order to enhance the efficiency of a blue-green laser through spectrum conversion of the pumping light, a converter dye BBQ was mixed in the laser dye solutions. The laser was pumped with a plasma radiation source. The increase of laser output over the maximum obtainable from the pure dye operation was better than 80% for the dye mixture of LD490+BBQ or coumarin 503+BBQ. The estimated enhancement calculated by a simple spectrum conversion model agrees well with the experimental results. The enhancement is mainly effected by irradiance in the UV from the pumping source, the fairly good match of the fluorescence band of converter dye with the absorption band of the laser dye, and the lack of the overlap of the fluorescence band of the laser dyes with the triplet–triplet absorption band of the converter dye used.

Notes: A new nuclear magnetic resonance (NMR) flow-velocity-imaging method applied to the study of the fluid dynamics is introduced. In the proposed technique, a selection gradient is used for the phase encoding, and since the selection gradient is relatively small compared with the conventional gradient for phase encoding it allows the measurement of high-velocity flow. To obtain the phase-velocity relationship, the Bloch equation is solved numerically and establishes the quantitative phase-velocity relationship of the flow under the slice selection gradient and echo radio frequency pulse. The flow effect compensation in the directions other than the slice selection direction is achieved by applying additional flow coding gradients similar to the conventional flow phase coding. The experimental NMR flow images obtained with the new technique are compared with the velocity measurements made with a laser Doppler velocimeter, and are found to be in close agreement.

Notes: Growth of gallium oxide on n-GaN was realized in H2O by bias-assisted photoelectrochemical (PEC) oxidation using Al as a counterelectrode instead of a Pt commonly used in the PEC process. Although the growth of the oxide was not observed at below 2 V, the initial oxide growth rate of 8.7 nm/min was shown at a bias of 15 V and ultraviolet light intensity of 300 mW/cm2. However, the growth rate lowered and oxide thickness was saturated to 340 nm. The saturated oxide thickness and initial growth rate were increased with the applied bias. The homogeneous oxide growth and near stoichiometric composition of Ga2O3 were observed in Auger electron spectroscopy analysis results. © 2002 American Institute of Physics.

Notes: Temperature-dependent Hall effect measurements on unintentionally doped n-type GaN epilayers show that, above room temperature, the Hall-mobility values of different samples vary parallel with each other with temperature. We demonstrate that this anomaly is mainly due to a conductive layer near the GaN/sapphire interface for thin samples with low carrier density. Through trapping electrons, threading edge dislocations (TEDs) debilitate the epilayer contribution in a two-layer mixed conduction model involving the epilayer and the near-interface layer. The trapping may, in part, explain low mobility and anomalous transport in pure GaN layers. Scattering by TEDs is important only at low temperatures. © 2000 American Institute of Physics.