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This article presents an integrated approach to strategic change. The traditional 2 x 2 matrix is replaced with a 'Change Wheel' which corporate executives and managers can use to 'navigate' change. The author argues for an alignment of strategies with the change processes, and the company cultures required to sustain the strategic change. He identifies the change processes specific to each change strategy, and emphasizes the importance of ensuring that appropriate change processes are in place. The article is based on 3 years' research and provides practical guidelines to business executives who are involved in designing and implementing strategic change.

Hydraulic power units for mobile equipment play by a different set of design rules than those used for industrial hydraulic systems. Correctly sizing an electric motor for a hydraulic power [...]

To determine whether patients with Alzheimer disease (AD) compensate for neuropathologic changes when performing a mnemonic task by recruiting 1) the same brain regions as age-matched, healthy controls, but to a greater extent; 2) additional brain regions not activated by controls; or 3) both.

Bollobás and Thomason showed that every 22k‐connected graph is k‐linked. Their result used a dense graph minor. In this paper, we investigate the ties between small graph minors and linkages. In particular, we show that a 6‐connected graph with a K9−minor is 3‐linked. Further, we show that a 7‐connected graph with a K9−minor is (2,5)‐linked. Finally, we show that a graph of order nand size at least 7n−29 contains a K9−−minor. © 2005 Wiley Periodicals, Inc. J Graph Theory 49: 75–91, 2005

AbstractThe Palaeogene Slieve Gullion Igneous Complex comprises a layered central intrusion surrounded by a slightly older ring dyke. The ring dyke contains two major intrusive rock types. About 70% of the ring dyke is occupied by porphyritic granophyre and 30% by porphyritic felsite. Locally complex relationships between the two lithologies are observed. Major and trace element compositions suggest that there are two distinct chemical groups within each lithology: a Si-rich felsite, concentrated in a ~1 m wide zone at the outer margins of the dyke which grades into a less Si-rich felsite towards the interior. Similarly, a Si-rich granophyre, concentrated in the centre of the intrusion grades outwards into a Si-poor granophyre facies.These rock relationships and geochemical variations suggest that a complex magma chamber hosted a stratified granitic magma body and various wall/floor magma facies. Low density, high-Si felsite magma from the top of the chamber was tapped first, followed by less Si-rich felsite magma as evacuation proceeded. The granophyres probably originate from the chamber walls/floor, representing more mushy equivalents of the felsite magma. Little granophyre magma was tapped during the early stages of the evacuation sequence. As evacuation continued, probably aided by trap-door caldera collapse, the ‘granophyre magmas’ intruded the already emplaced and slightly cooled felsite, forming the complexly zoned structure of the Slieve Gullion ring intrusion.

The interaction of sodium tetrachloropalladate(II) with the potentially tridentate aminophosphine bis[2-(diphenylphosphino)ethyl]amine (PNHP) in 1∶1 molar ratio leads to the formation of the four-coordinate complex [Pd(PNHP)Cl]Cl (1). Complex 1 undergoes chloro substitution reactions with NaX (X = Br, I), CuCl, AgNO₃, the amino acid N-acetyl-L-cysteine (AcCysSH) and the tripeptide reduced glutathione (γ-L-Glu-L-Cys-Gly, GSH) affording [Pd(PNHP)X]X' [X = X' = Br (2), I (3), NO₃ (4); X = Cl, X' = CuCl₂ (1a); X' = Cl, X = RS = AcCysS (8), GS (9)]. However, gold(I) induces abstraction of the aminophosphine from the ionic complexes 1 and 2 to produce the neutral compounds Au₂(PNHP)X₂ [X = Cl (5), Br (6)]. The dinuclear complex Au₂(PN(NO)P)Cl₂ (5a), containing the ligand bis[2-(diphenylphosphino)ethyl]nitrosylamine, was formed by reaction of 4 with gold(I) in the presence of traces of nitrosyl chloride. Addition of one molar equivalent of PNHP to 1 results, by a ring-opening process, in the formation of [Pd(PNHP)₂]Cl₂ (7) in which the palladium is five-coordinate. The ionic complexes 1, 2 and 4 were shown by X-ray diffraction to be distorted square-planar and complex 2 has a N–H⋯Br bond of 2.371 Å with the ligand adopting a boat conformation. The X-ray crystal structure of the novel neutral compound 5a shows linear P–Au–Cl arrangements with intermolecular Au⋯Au interactions of 3.0412(9) Å.

The rapid expansion of supercritical solutions (RESS) process is a promising method for the production of ultrafine powders and aerosols of narrow size distribution for coatings and other applications. In this article, part 2 of a two-part study, the nucleation and subsequent growth of 2500 Mw perfluoropolyether diamide (PFD) from supercritical carbon dioxide (CO2) by expansion through a small-diameter nozzle is modeled in a three-stage, multidimensional fashion. The stages include a hydrodynamic solution, solvent−solute phase equilibria analyses, and an aerosol transport model. The hydrodynamics model successfully captures the vapor−liquid transition that occurs as carbon dioxide is expanded to ambient conditions. Cloud-point pressures and equilibrium compositions of the separated solvent−solute system are determined and are used in a multidimensional aerosol transport model. This model incorporates various mechanisms influencing droplet growth. Parametric studies are conducted to investigate the influences of the interfacial tension, the equilibrium addition of carbon dioxide, and the diffusion coefficient on the predicted droplet diameter. Turbulent coagulation in the ambient region downstream of the expansion nozzle is found to be the dominant mechanism responsible for the production of micron-sized droplets observed in companion experiments.

The rapid expansion of supercritical solutions (RESS) process is a promising environmentally benign technology for fine droplet or particle formation. The absence of organic solvents and narrow size distribution of RESS precipitates make this process attractive for polymer coating applications. In our work, this technique has been used to produce droplets of perfluoropolyethers from CO2 solutions without the aid of cosolvents for the coating of porous materials applied in monumental and civil infrastructures. The present work is aimed at gaining an understanding of the relationship between droplet and spray characteristics and RESS process conditions. As such, a combined experimental/computational approach is applied to a representative binary system consisting of a low-molecular-weight perfluoropolyether diamide (PFD) dissolved in supercritical CO2. Part 1 of this work presents phase equilibria measurements and polymer droplet size characterizations under different operating conditions. The effects of temperature, solute concentration, and nozzle configuration on droplet and spray characterization and transfer efficiency are discussed. Part 2 of this work presents a multidimensional computational fluid dynamics model of the RESS expansion process and describes the use of the model in further analyzing and interpreting experimental data.

This study continues the collection of data on the anterior adhesive areas and secretions of monopisthocotylean monogenean (flatworm) parasites and begins an investigation of their phylogenetic usefulness. Here, two species of parasitic worms from an elasmobranch, Troglocephalus rhinobatidis (Monocotylidae: Dasybatotreminae) and Neoheterocotyle rhinobatidis (Monocotylidae: Heterocotylinae), are compared and contrasted. It has been suggested in recent literature that these two taxa are more closely related than is currently recognised. Our data support this view. Both species have multiple apertures on the ventral anterior margin through which adhesive is secreted. Two types of secretion exit from multiple adjacent duct endings terminating in each aperture: rod-shaped (S1) and spherical-shaped (S2) bodies. S1 bodies of both species show nano-banding of similar size and are membrane bound. Ultrastructure of the glands, ducts, duct endings and secreted adhesive is similar for both species, but aperture shape differs. Away from the adhesive areas, tegumental inclusions are found to differ between the two species and another, apparently non-adhesive, secretion is found in N. rhinobatidis.

It remains unknown whether the extent of vasoactive response to exogenous calcitonin gene-related peptide (CGRP) varies among different regional vascular beds. It is also unclear whether endogenous CGRP plays a functional role in regulating basal vascular activity. To address these two issues, experiments were conducted in 27 anesthetized rats instrumented with a carotid flow probe and catheters in a jugular vein, left ventricle (LV), and femoral artery, and in 6 conscious dogs, chronically instrumented with LV pressure gauge, aortic and atrial catheters, and ascending aortic, coronary, carotid, and renal flow probes. In both species, administration of human alpha-CGRP (0.1-0.5 microg/kg, i.v.) induced a dose-dependent peripheral vasodilation that was completely abolished by pretreatment with alpha-CGRP[8-37] (30 microg/kg/min, i.v.), a competitive antagonist of CGRP receptors. Regional blood flow measured by the radioactive microsphere technique in rats showed that the alpha-CGRP (0.3 microg/kg, i.v.)-induced increase in blood flow was greater (p < 0.05) in the heart (+53 +/- 16%) than in the brain (+14 +/- 6%). In the presence of beta-adrenergic receptor blockade with propranolol, however, the increases in blood flow in these two vascular beds were identical. In conscious dogs, alpha-CGRP (0.3 microg/kg, i.v.) produced similar increases in coronary (+24 +/- 6%), carotid (+26 +/- 3%), and renal (+26 +/- 6%) blood flow, which were different from the patterns induced by other vasodilators; at an equivalent level of reduction in mean arterial pressure and total peripheral resistance, alpha-CGRP increased coronary and carotid blood flow significantly less (p < 0.05) than adenosine or nitroprusside. Unlike alpha-CGRP, adenosine and nitroprusside, as expected, induced pronounced differential blood flow changes in these vascular beds. Neither systemic hemodynamics nor regional blood flow distribution was altered by the administration of a pharmacological blocking dose of alpha-CGRP[8-37] in the two species. Thus, we conclude that endogenous alpha-CGRP does not play an important role in cardiovascular regulation under normal, resting conditions, although exogenous alpha-CGRP induces a marked, comparable vasorelaxation in different regional vascular beds.

Murine antibodies, raised against a purified recombinant 30 kDa laminin-binding protein from Echinococcus granulosus, were used to investigate the tissue distribution of the native protein in protoscoleces and brood capsules. Immunofluorescence, in combination with confocal microscopy, revealed that the protein was distributed in small annular foci near the peripheral regions of the protoscoleces. Immunoelectron microscopy of thawed cryosections demonstrated that the laminin-binding protein was present in the cytoplasm of tegumentary cytons and myocytons, but not in cells of the excretory system. The protein was associated with amorphous regions of the cytoplasm, and was not expressed at the surfaces of cells. This distribution resembles those of other invertebrate laminin-binding proteins, which are thought to act in the cell cycle and cell proliferation events. A low degree of label was consistently detected in extracellular matrices of the protoscolex.

The synthesis and pharmacology of 4, a potent thienothiophene non-peptide fibrinogen receptor antagonist, are reported. Compound 4 inhibited the aggregation of human gel-filtered platelets with an IC50 of 8 nM and demonstrated an 8-fold improvement in affinity for isolated GPIIb/IIIa receptors over analogues possessing an isoindolinone backbone. Flow cytometry studies revealed that the binding of 4 to resting platelets is a diffusion-controlled process (kon = 3.3 × 10⁶ M^-1 s^-1) and that 4 binds to dog and human platelets with comparable affinity (Kd = 0.04 and 0.07 nM, respectively). Ex vivo platelet aggregation in dogs was completely inhibited by an iv dose of 5 mg/kg, and an oral dose of 50−90 mg/kg followed by low daily doses of 10 mg/kg was sufficient to maintain ~80% inhibition of ex vivo platelet aggregation over several days. Inhibition of ADP-induced platelet aggregation in anesthetized dogs at 77 ± 7% resulted in a moderate 2.5-fold increase in bleeding time, while complete inhibition (100%) resulted in an approximately 10-min bleeding time. Additional doses were required to increase the bleeding time to the maximum time allowed in the protocol (15 min), thus indicating a potentially useful and safe separation of efficacy and bleeding time.

Abstract:  Two-point LDA measurements are shown to be strongly affected by both geometric and coincidence timing parameters, some effects of which are akin to those previously documented for nonorthogonal three-component LDAs. High spatial resolution is shown to be a necessity for small scale two-point measurements. It is suggested that a maximum effective probe volume dimension of one Kolmogorov length be considered as an upper bound for lateral and spanwise correlation measurements if microscale estimates are intended. However, if the effective probe volume shape is roughly spherical and a proper coincidence window is chosen, the spatial resolution of longitudinal correlation measurements appears to be independent of probe dimension.

The antiplatelet activity of L-734,217, a nonpeptide platelet GPIIb/IIIa antagonist, was evaluated in the rat, guinea pig and dog. IC50 for inhibition of in vitro platelet aggregation for these species (agonists: adenosine diphosphate, collagen) were rat, 838,000 and > 1,100,000 nM; guinea pig, 124 and 156 nM; dog, 42 and 50 nM. In an in vivo rat/in vitro dog platelet aggregation assay, effective antiaggregatory plasma concentrations of L-734,217 were achieved after 8.0 to 16.0 mg/kg p.o. vs. 0.3 to 1.0 mg/kg i.v. to rats. Delays in platelet-dependent hemostatic plug formation in severed mesenteric arteries were observed after 2.0 to 5.0 mg/kg p.o. vs. 0.1 to 0.2 mg/kg i.v. to guinea pigs. Dose-dependent inhibitions of ex vivo platelet aggregation after 0.3 to 3.0 mg/kg p.o. and 0.03 to 0.3 mg/kg i.v. L-734,217 to conscious dogs yielded estimates of 8 to 16% oral bioavailability. The antiplatelet activity of 3.0 mg/kg p.o. L-734,217 in dogs was unaffected by dosage form or food. In a conscious dog model of left circumflex coronary artery electrolytic lesion, 3.0 mg/kg p.o. L-734,217 q4 to 8 hr reduced thrombus mass, prevented occlusive coronary artery thrombosis and reduced or prevented myocardial infarction and ventricular ectopy. In anesthetized dogs, a dissociation between inhibition of ex vivo platelet aggregation and template bleeding time prolongation was observed with i.v. L-734,217. The results of the coadministration of heparin, aspirin and L-734,217 to anesthetized dogs suggested a synergistic effect on template bleeding time with no effect on plasma L-734,217 concentrations. These findings indicate L-734,217 to be an important lead structure for the development of therapeutically useful oral antiplatelet agents.

The proteolipids (PLPs) are abundant components of mammalian CNS myelin. Recombinant DNA methodologies have enabled us to search for evolutionary antecedents of PLP/DM20. Polymerase chain reactions ofTorpedo andSqualus brain cDNA were performed with degenerate primers designed according to the mammalian PLP/DM20 sequence. Three DM20-related products (DMa, DMß, and DM?) were amplified; no cDNAs containing the PLP-specific segment were found. Regions of the DMa and DM? are similar to the pore-forming segments of certain ligand-gated channels. In embryonicSqualus CNS, DMa and DM? appear to be co-expressed with Po. Antiserum raised against Torpedo DMa recognizes a protein in mouse CNS myelin, demonstrating that at least one of the newly recognized fish DMs is also in mammals. Our data, as well as that of other laboratories, supports the existence of a ubiquitously expressed proteolipid gene family.

Summary Schwann cells, which form and maintain extensive myelin sheaths, have the bulk of their lipid and protein synthesis restricted to the compact ‘perinuclear’ zone at the centre of the internode. Using teased fibre and quantitative electron microscopical autoradiography, we demonstrated that additional protein-synthesis takes place in the lengthy processes of Schwann cell cytoplasm. This ‘so-called’ superficial cytoplasmic channel network forms a branching and anastomozing array that stretches between the perinuclear region and the distant paranodes. Protein synthesis apparently does not extend from this surface network into the Schmidt-Lanterman incisures or paranodal loops that circumscribe compact myelin. To maintain protein synthesis in these lengthy processes, Schwann cells transport a portion of their RNA along the superficial cytoplasmic channels at a rate (0.1 mm per day) that appears to be slightly lower than the transport rate reported for RNA along dendrites of hippocampal neurons in culture (0.5 mm per day). Nearly a week is required for labelled RNA to be transported from the Schwann cell nucleus to the paranodal terminals of the longer channels. The existence of this extended protein synthesis is not limited to myelinating Schwann cells. Schwann cell processes associated with small calibre axons also appear to synthesize some of their own proteins as the RNA needed to catalyze local translational events is transported into these processes.

Thin films of Pt-doped SnO2 were prepared by RF magnetron sputtering onto glass substrates maintained at room temperature. Gold electrodes were provided by conventional vacuum evaporation to form sandwich structures. X-ray diffraction measurements confirmed the films to be of an amorphous structure. Room temperature d.c. measurements showed a dominant Poole-Frenkel conduction process at low applied voltages, both under vacuum and in ambient air, but the results of the latter exhibited localized field enhancement caused by various adsorbed oxygen species. At higher voltages space-charge-limited conductivity was observed, with the temperature parameter characterizing the exponential trap distribution decreasing from approximately 1500 to 1050 K as a result of the oxygen adsorption. A.c. conductivity was characterized by an angular frequency, O, dependence of the form Os with an indexs < 1, and was associated with a relaxation process due mainly to a charge-carrier hopping mechanism. Both capacitance and loss tangent decreased with increasing frequency, in accordance with existing theory for samples provided with ohmic contacts.

Data from a two-component dual-beam laser-Doppler Velocimeter were used to evaluate four different velocity bias correction methods. The data were collected over a range of valid data rates from 100 Hz to 20 kHz at four flow locations in a shear layer. Turbulence intensities ranged from 15 to 100 percent. Flow statistics were calculated using these proposed velocity bias correction techniques. The results were compared to the unbiased values, which were obtained using an approximated equal-time sampling technique. Some of the correction schemes performed well at low turbulence levels, but became ineffective at high turbulence levels. One ad hoc empirical correction scheme showed relatively good results throughout.

Abstract:  An investigation was performed in grid-generated turbulence to highlight the difficulties in estimating integral and microscales from discrete autocorrelation measurements made using a burst-mode laser Doppler anemometer (LDA). Comparison was made to hot-wire results and the theoretical growth laws determined by the decay of turbulent energy. The chief concern was the presence of a spike in the measured autocorrelation coefficient functions at t=0. It was found that renormalizing the autocorrelation to a value at t=0 determined by “backfitting” a quadratic equation to the slots near t=0 led to microscale estimates that showed the same trend as the decay law and were in agreement with those determined using a hot-wire. Additionally, practical guidelines are presented for making accurate autocorrelation measurements by LDA.

A new quality control system (QC) dedicated to dental radiology was clinically tested at 5 locations evaluating 10 dental x-ray units with 4 automatic and 10 manual processing systems. The new QC system was found to be easy to use, reduced film processing errors and in one instance saved money. The system did not have any major impact on clinical radiation exposure factors. Generally, the dental auxiliaries did not like using the QC system as it interfered with other dental tasks. Dentists were mildly indifferent and too busy to be intimfately involved in the QC system. Motivation to undertake a QC program will come only if the dentist and dental auxiliaries are educated to believe that quality assurance in dental radiology is beneficial.