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Selected AbstractsMalignant pheochromocytoma with progressive paraparesis in von Hippel,Lindau diseaseEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2000R. Mössner Pheochromocytomas are a feature of the von Hippel,Lindau disease spectrum, a multisystem disorder of autosomal dominant inheritance. Pheochromocytomas are, however, observed during life with a lower frequency than other features of this disease, such as retinal angiomas, haemangioblastomas of the CNS, and renal carcinomas. We present the highly unusual case of a patient who required an emergency operation for an intradural extramedullary thoracic tumour which was clinically suggestive initially of neurinoma. We present evidence from NMR, histological and isotope scan investigations of this being a pheochromocytoma metastasis and of an additional right-sided paraganglioma at the same height. A detailed history revealed that this patient had suffered from four other pheochromocytomas and two other paragangliomas, in addition to retinal angiomatosis of von Hippel,Lindau disease. This case is extraordinary due to (i) the unusual site of the metastasis, (ii) the neurological requirement for an emergency operation of pheochromocytoma, (iii) metastasis of pheochromocytoma in von Hippel,Lindau disease (only eight previous cases), and (iv) the number of recurrent pheochromocytomas. It clearly demonstrates the necessity for frequent and life-long follow-up in von Hippel,Lindau disease. [source] Structural biomass partitioning in regrowth and undisturbed mesquite (Prosopis glandulosa): implications for bioenergy usesGCB BIOENERGY, Issue 1 2010R. JAMES ANSLEY Abstract Honey mesquite (Prosopis glandulosa Torr.) which grows on grasslands and rangelands in southwestern USA may have potential as a bioenergy feedstock because of existing standing biomass and regrowth potential. However, regrowth mesquite physiognomy is highly different from undisturbed mesquite physiognomy and little is known regarding growth rates and structural biomass allocation in regrowth mesquite. We compared canopy architecture, aboveground biomass and relative allocation of biomass components in regrowth (RG) trees of different known ages with undisturbed (UD) trees of similar canopy height to each RG age class. RG trees in most age classes (2,12 years old) had greater canopy area, leaf area, basal stem number, twig (<0.5 cm diameter) mass and small stem (0.5,3 cm diameter) mass than UD trees of the same height. Large stem (>3 cm diameter) mass was similar between RG and UD trees in all height classes. Ages of UD trees were determined after harvest and further comparisons were made between age, canopy structure and biomass in RG and UD trees. Relationships between age and total mass, age and height, and age and canopy area indicated a faster growth rate in RG than in UD trees. Large stem mass as a percentage of total tree mass accumulated more rapidly with age in RG than UD trees. Leaf area index and leaf : twig mass ratio were maintained near 1 in all RG and UD trees. Regrowth potential may be one of the most important features of mesquite in consideration as a bioenergy feedstock. [source] Wide-range length metrology by dual-imaging-unit atomic force microscope based on porous aluminaMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2004Dongxian Zhang Abstract A new dual-imaging-unit atomic force microscope (DIU-AFM) was developed for wide-range length metrology. In the DIU-AFM, two AFM units were combined, one as a reference unit, and the other a test one. Their probes with Z piezo elements and tips were horizontally set in parallel at the same height to reduce errors due to geometric asymmetry. An XY scanner was attached to an XY block that was able to move in the X direction with a step of about 500 nm. A standard porous alumina film was employed as the reference sample. Both reference sample and test sample were installed at the center of the XY scanner on the same surface and were simultaneously imaged. The two images had the same lateral size, and thus the length of the test sample image could be accurately measured by counting the number of periodic features of the reference one. The XY block together with the XY scanner were next moved in the X direction for about 1.5 ,m and a second pair of reference and test images were obtained by activating the scanner. In this way, a series of pairs of images were acquired and could be spliced into two wide-range reference and test images, respectively. Again, the two spliced images were of the same size and the length of test image was measured based on the reference one. This article presents a discussion about the structure and control of the DIU-AFM system. Some experiments were carried out on the system to demonstrate the method of length calculation and measurement. Experiments show a satisfactory result of wide-range length metrology based on the hexagonal features of the porous alumina with a periodic length of several tens of nanometers. Using this method the DIU-AFM is capable of realizing nanometer-order accuracy length metrology when covering a wide range from micron to several hundreds of microns, or even up to millimeter order. Microsc. Res. Tech. 64:223,227, 2004. © 2004 Wiley-Liss, Inc. [source] The influence of background wind direction on the roadside turbulent velocity field within a complex urban streetTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 635 2008R. J. Smalley Abstract The turbulent velocity field within a complex urban street in the city of York, United Kingdom was measured over a one-month period, with data coverage over a wide range of background wind directions, ,ref (where ,ref = 0° is relative to the street axis, and angles increasing clockwise). Within the street, a persistent mean-flow cross-street circulation exists for 15° ,,ref < 165° in addition to possible flow convergence for 240° ,,ref < 300° . The magnitude of the in-street normalised turbulent kinetic energy (TKE) is dependent on the type of predominant in-street mean-flow structures. During conditions that correspond to mean-flow cross-street circulation, the TKE is approximately twice the magnitude on the windward side compared with the leeward side. For nearly all wind directions, and on both sides of the street, the TKE is approximately constant with height for 0.4 < z/H < 0.8. There is evidence that the in-street TKE increases with background TKE when other meteorological influences are relatively constant. For background wind directions free from mean flow convergence, the least variability in the sector-averaged turbulence data occurs when the TKE is normalised by the in-street mean wind speed, rather than the background wind speed. The two-point cross-correlation of the vertical-velocity component fluctuations on the windward side is at least 0.6 between the mid and upper anemometers. The two-point cross-correlation between cross-street (same height) vertical-velocity component fluctuations is negative and non-negligible during mean-flow circulation, which indicates possible cross-street coherence in the turbulent velocity field. The turbulent Reynolds stress anisotropy tensor, which provides an indication of the level of TKE redistribution between the components, and the overall level of turbulence anisotropy, is discussed with reference to the mean-flow structures within the street. Copyright © 2008 Royal Meteorological Society [source] | ||||||||||