Isolated ovarian polyarteritis nodosa

Polyarteritis nodosa is a rare disorder and a form of systemic vasculitis. A 48 year-old female was admitted to the hospital because menorrhagia and pelvic pain in February 1993. The patient underwent exploratory laparotomy resulting in a total hysterectomy and bilateral salpingo-oophorectomy for myoma of uterus and a right adnexal cystic mass. Histopathologic examination revealed left ovarian periarteritis nodosa. Further investigation and 9 months follow-up failed to show any systemic involvement. To our knowledge the isolated ovarian polyarteritis nodosa is the first case in the literature.     

Tailoring of Surfaces with Ultrathin Layers for Controlled Binding of Biopolymers and Adhesion and Guidance of Cells

Various strategies are described for the bio-functionalization of solid substrates by design of interfacial architectures. The first approach is based on the self-assembly process of long-chain thiol molecules from solution to a (noble) metal surface. If some of these building blocks carry a binding site (ligand) for proteins (receptors, antibodies, etc.) the metal surface can be tailored for maximum specific binding while simultaneously minimizing nonspecific adsorption. The second concept is based on polymers that are covalently attached to (oxide) surfaces. The preparation of these (end-) grafted functional polymers involves either the binding of preformed macromolecules to corresponding sites at the surface of the support or the recently introduced “grafting-from” method, by which an initiator molecule is first covalently bound to the surface and then activated — either by heat or light — in the presence of suitable monomer units such that a polymer chain grows from the solid/solution interface. Finally, the functionalization of patterned surfaces by peptide chains that mimic the binding domains of cell adhesion proteins is summarized. It is demonstrated that not only the selective adhesion of neuronal cells can then be controlled, but also their development with the outgrowth of dendrites and axons.     

Comparison of Formulae for the Determination of Fluorescent and Non–fluorescent Whiteness

The prediction capabilities of simple whiteness formulae based on photometer reflectance readings (A, G, B) as compared to linear formulae with adjustable parameters based on chromaticity values (x, y, Y) have been investigated. For each formula, the instrumentally determined whiteness was compared with visually estimated whiteness using the plates of the Ciba–Geigy Plastic White (CGPW) Scale as a standard. This was carried out for a set of 48 fluorescent cotton cloth samples previously studied, as well as for a new set of 86 non–fluorescent cotton cloth samples. As expected, the AGB formulae were inferior to those based on chromaticity values; however, the Taube formula performed quite well for fluorescent samples. On the set of non–fluorescent samples, a formula having green hue preference was required; the Berger formula was found to be the most successful among the simple AGB formulae.     

HDL3-mediated cholesterol efflux from cultured enterocytes: The role of apoproteins A-I and A-II

High density lipoproteins (HDL) were recently demonstrated in an enterocyte model (CaCo-2 cells) to mediate reverse cholesterol transport by retroendocytosis. The present study was carried out to define the role of the major HDL apoproteins (apo) A-I and apo A-II in this pathway. HDL₃ was fractionated by heparin affinity chromatography into the two main fractions containing either apo A-I only (fraction A) or both apo A-I and apo A-II (fraction B). In addition, liposomes were reconstituted from purified apo A-I or apo A-II and dimyristoyl phosphatidylcholine. The cell binding properties and cholesterol efflux potential were studied in the lipoprotein fractions and the liposomes. Both fractions exhibited similar maximal binding capacities of 4427 (A) and 5041 (B) ng/mg cell protein, but their dissociation constants differed (40.5 and 167.7 μg/mL, respectively). Fraction A induced cholesterol efflux and stimulated cholesterol synthesis more than did fraction B. Fraction A mobilized both cellular free and esterified cholesterol, whereas fraction B preferentially mobilized cholesteryl esters. Liposomes, containing either apo A-I or apo A-II, showed specific binding, endocytosis and endosomal transport, and were released as intact particles. Apo A-I liposomes also mediated cholesterol efflux. In conclusion, there is evidence that the HDL₃ subfractions A and B, as well as reconstituted liposomes containing either apo A-I or apo A-II, were specifically bound and entered a retroendocytosis pathway which was directly linked to cholesterol efflux. Quantitatively, the apo A-I subfraction appeared to play the dominant role in normal enterocytes. The apo A-II content of fraction B was related to the mobilization of cholesteryl esters.     

The carbon-isotopic composition of Proterozoic carbonates: Riphean successions from northwestern Siberia (Anabar Massif, Turukhansk Uplift)

Thick carbonate-dominated successions in northwestern Siberia document secular variations in the C-isotopic composition of seawater through Mesoproterozoic and early Neoproterozoic (Early to early Late Riphean) time. Mesoproterozoic dolomites of the Billyakh Group, Anabar Massif, have delta 13C values that fall between 0 and -1.9 permil versus PDB, with values in the upper part of the succession (Yusmastakh Formation) consistently higher than those of the lower (Ust'-Il'ya and Kotuikan formations). Consistent with available biostratigraphic and radiometric data, delta 13C values for Billyakh carbonates compare closely with those characterizing early Mesoproterozoic carbonates (about 1600-1200 Ma) worldwide. In contrast, late Mesoproterozoic to early Neoproterozoic limestones and dolomites in the Turukhansk Uplift exhibit moderate levels of secular variation. Only the lowermost carbonates in the Turukhansk succession (Linok Formation) have delta 13C values that approximate Billyakh values. Higher in the Turukhansk succession, delta 13C values vary from -2.7 to +4.6 permil (with outliers as low as -5.0 permil interpreted as diagentically altered). Again, consistent with paleontological and radiometric data, these values compare well with isotopic values from 1200 to 850 Ma successions elsewhere. Five sections measured in different parts of the Turukhansk basin show nearly identical patterns of variation, confirming that carbonate delta 13C correlates primarily with time and not facies. The Siberian sections illustrate the potential of integrated biostratigraphic and chemostratigraphic data in the intra- and interbasinal correlation of Mesoproterozoic and early Neoproterozoic rocks.     

Robust Cardiac Function Assessment in 4D PC‐MRI Data of the Aorta and Pulmonary Artery

Four‐dimensional phase‐contrast magnetic resonance imaging (4D PC‐MRI) allows the non‐invasive acquisition of time‐resolved, 3D blood flow information. Stroke volumes (SVs) and regurgitation fractions (RFs) are two of the main measures to assess the cardiac function and severity of valvular pathologies. The flow rates in forward and backward direction through a plane above the aortic or pulmonary valve are required for their quantification. Unfortunately, the calculations are highly sensitive towards the plane's angulation since orthogonally passing flow is considered. This often leads to physiologically implausible results. In this work, a robust quantification method is introduced to overcome this problem. Collaborating radiologists and cardiologists were carefully observed while estimating SVs and RFs in various healthy volunteer and patient 4D PC‐MRI data sets with conventional quantification methods, that is, using a single plane above the valve that is freely movable along the centerline. By default it is aligned perpendicular to the vessel's centerline, but free angulation (rotation) is possible. This facilitated the automation of their approach which, in turn, allows to derive statistical information about the plane angulation sensitivity. Moreover, the experts expect a continuous decrease of the blood flow volume along the vessel course. Conventional methods are often unable to produce this behaviour. Thus, we present a procedure to fit a monotonous function that ensures such physiologically plausible results. In addition, this technique was adapted for the usage in branching vessels such as the pulmonary artery. The performed informal evaluation shows the capability of our method to support diagnosis; a parameter evaluation confirms the robustness. Vortex flow was identified as one of the main causes for quantification uncertainties.     

Morphology and crack toughness behaviour of nanostructured block copolymer/homopolymer blends

The crack initiation and propagation behaviour of styrene-butadiene (SB) star block copolymer/polystyrene blends (ST3/PS) forming PS-rich and polybutadiene (PB)-rich nanosized domains by self-assembling have been investigated using the essential-work-of-fracture (EWF) approach. Three morphological transitions have been observed, which are crucial to understand the crack toughness behaviour: (i) 0-30 wt.% PS homopolymer: A co-continuous domain structure of PS-rich and PB-rich domains has been observed. For PS homopolymer fraction (?_PS) < 10 wt.% PS homopolymer (i.e. only pure ST3) the rubbery PB-rich phase forms the major phase and for ?_PS > 10 wt.% the glassy PS-rich phase. (ii) At 40-60 wt.% PS homopolymer, a layer-like morphology is formed where the PS-rich layer thickness is ?50 nm, a critical dimension, which is crucial for understanding the ductile-to-semiductile transition. (iii) For 80 wt.% PS homopolymer, PS-rich phase starts to form the matrix combined with a transition from shear stress dominated (shear yielding) to normal stress dominated behaviour (PS-like crazes). The co-continuous morphology at 20 wt.% and 30 wt.% PS is capable of improving toughness of block copolymers, demonstrated by the observed maximum in the non-essential work of fracture and thus explaining a new way of toughening of polymers while retaining high transparency. The correspondence between the ductile-to-semiductile transition and the change in the shape of plastic zone from circular to elliptical as revealed from strain field analysis could be clearly reaffirmed by the observed transition from shear to normal force induced deformation in the fractured surface analysis of these blends. The conceptual correspondence of βw_p and w_e with T_J and δ_0.2 respectively reveal that resistance against crack propagation (βw_p and T_J) is morphology sensitive while the resistance against crack initiation (w_e and δ_0.2) is matrix sensitive.     

A new approach for handling and transferring of thin semiconductor materials

 Based on the fracture mechanics analysis of crack propagation, the phenomenon of subcritical crack growth was utilized for a controlled debonding of directly wafer-bonded interfaces. The approach allowed the well-defined separation of bonded wafers although the bond strength was high due to thermal annealing. The achieved splitting velocity depended on the wafer material, the wafer thickness ratio, the bonding process parameters, and the environmental conditions during cleaving. In combination with wafer bonding, the method can be used for a temporary stiffening and handling of thin and brittle wafers during fabrication, even if the wafers are exposed to high process temperatures. The approach can also be applied to fabricate micromechanical systems (MEMS). Received: 12 July 2001/Accepted: 26 February 2002 This paper was presented at the Conference of Micro System Technologies 2001 in March 2001.     

Distinguishing between green building occupants’ reasoned and unplanned behaviours

Several frameworks incorporate social and psychological elements of environmentally significant behaviour, and most assume cognitive and deliberate decision-making. Household energy consumption behaviours, however, span a spectrum from reasoned and deliberate to unplanned and automatic. The aim of this paper is to advance knowledge of reasoned and unplanned behaviours in the context of pro-environmental action. Using results of a survey administered to occupants of an urban residential green building, this study explores five household consumption behaviours and tests the hypothesis that unplanned behaviours will be poorly predicted by a reasoned, values-based behavioural framework. Using path analyses, variables in a values-based framework are used to predict surveyed behaviours. Findings indicate that behaviours hypothesized to be unplanned were not well predicted by the values-based framework. The framework successfully predicted what was hypothesized to be a fully reasoned behaviour. Three potential reasons are discussed for the lack of prediction of some behaviours. A deeper understanding of how unplanned, automatic or habitual behaviours intervene in conservation intentions can help policy-makers and building designers better respond to influences of occupant behaviour on building performance.