Dislocation after total hip replacement: there is no such thing as a safe zone for socket placement with the posterior approach

Introduction Malorientation of the socket contributes to instability after hip arthroplasty but the optimal orientation of the cup in relation to the pelvis has not been unequivocally described. Large radiological studies are few and problems occur with film standardisation, measurement methodology used and alternative definitions of describing acetabular orientation. Methods A cohort of 1,578 patients from a single institution is studied where all patient data was collected prospectively. Risk factors for patients undergoing surgery are analysed. Radiological data was compared between a series of non-dislocating hips and dislocating cases matched 2:1 by operation type, age and diagnosis. Results The overall dislocation rate for all 1,578 cases was 3.23% but the rate varied according to the type of surgery performed. The rate in uncomplicated primary cases was 2.4% which increased to 9.3% for second stage implantation for a two stage procedure for infection. There was no significant difference in the variability of the dislocating and non-dislocating groups for either inclination (p = 0.393) or anteversion (p = 0.661). Conclusions A “safe zone” for socket orientation to avoid dislocation could not be defined. The cause of dislocation is multifactorial, re-establishing the anatomic centre of rotation, balancing soft tissues and avoidance of impingement around the hip are important considerations.

Planar pursuit-evasion with variable speeds, part 1, extremal trajectory maps

Pursuit evasion in a plane is formulated with both players allowed to vary their speeds between fixed limits. A suitable choice of real-space coordinates confers open-loop optimality on the game. The solution in the small is described in terms of the individual players'' extremal trajectory maps (ETM). Each map is independent of role, adversary, and capture radius. An ETM depicts the actual real-space trajectories. A template method of generating constant control arcs is described. Examples of ETM for an aircraft flying at a constant altitude with fixed and varying speeds are presented.

Editorial of "International Journal of Critical Indigenous Studies Volume 1, Number 1, 2008"

We perceive the epistemological boundaries of Critical Indigenous Studies as marked by analyses of contemporary colonising power in its multiple forms in different contexts. This first issue brings together a diverse group of international Indigenous scholars who are politically and intellectually engaged in theorising from their respective standpoints as well as spatial and geographic locations. As such these essays enable dialogue across and within different colonial power contexts addressing epistemological ethical and methodological concerns within the broad field of Indigenous studies. In each essay a connecting theme is the need for intercultural and comparative work and to import Indigenous agency in the writing of history...

Purification and Regulatory Properties of Mung Bean (Vigna Radiata L.) Serine Hydroxymethyltransferase 1

Serine hydroxymethyltransferase, the first enzyme in the pathway for interconversion of C1 fragments, was purified to homogeneity for the first time from any plant source. The enzyme from 72-h mung bean (Vigna radiata L.) seedlings was isolated using Blue Sepharose CL-6B and folate-AH-Sepharose-4B affinity matrices and had the highest specific activity (1.33 micromoles of HCHO formed per minute per milligram protein) reported hitherto. The enzyme preparation was extremely stable in the presence of folate or L-serine. Pyridoxal 5'-phosphate, ethylenediaminetetraacetate and 2-mercaptoethanol prevented the inactivation of the enzyme during purification. The enzyme functioned optimally at pH 8.5 and had two temperature maxima at 35 and 55°C. The Km values for serine were 1.25 and 68 millimolar, corresponding to Vmax values of 1.8 and 5.4 micromoles of HCHO formed per minute per milligram protein, respectively. The K0.5 value for L-tetrahydrofolate (H4folate) was 0.98 millimolar. Glycine, the product of the reaction and D-cycloserine, a structural analog of D-alanine, were linear competitive inhibitors with respect to L-serine with Ki values of 2.30 and 2.02 millimolar, respectively. Dichloromethotrexate, a substrate analog of H4folate was a competitive inhibitor when H4folate was the varied substrate. Results presented in this paper suggested that pyridoxal 5'-phosphate may not be essential for catalysis.The sigmoid saturation pattern of H4folate (nH = 2.0), one of the substrates, the abolition of sigmoidicity by NADH, an allosteric positive effector (nH = 1.0) and the increase in sigmoidicity by NAD+ and adenine nucleotides, negative allosteric effectors (nH = 2.4) clearly established that this key enzyme in the folate metabolism was an allosteric protein. Further support for this conclusion were the observations that (a) serine saturation exhibited an intermediary plateau region; (b) partial inhibition by methotrexate, aminopterin, O-phosphoserine, DL-{alpha}-methylserine and DL-O-methylserine; (c) subunit nature of the enzyme; and (d) decrease in the nH value from 2.0 for H4folate to 1.5 in presence of L-serine. These results highlight the regulatory nature of mung bean serine hydroxymethyltransferase and its possible involvement in the modulation of the interconversion of folate coenzymes.

Amide-catalysed isomerisation of 5,6-dihydroisoquinolines: a novel synthesis of 1,2-dihydroisoquinolines

Knoevenagel condensation of 2-acylcyclohexanones or 2-ethoxycarbonylcyclohexanone with either cyanoacetamide or malononitrile followed by silver salt alkylation gave the 5,6,7,8-tetrahydroisoquinolines (3a–i). Chromic acid oxidation of the 5,6,7,8-tetrahydroisoquinolines (3a–i) to the corresponding tetralones (4a–i) followed by sodium borohydride reduction and p-toluenesulphonic acid-catalysed dehydration of the resulting alcohols (5a–i) gave the 5,6-dihydroisoquinolines (6a–i). Reaction of 5,6-dihydroisoquinolines (6a–g) with potassium amide in liquid ammonia gave a mixture of the 1,3-dihydroisoquinolines (7a–g) and the isoquinolines (8a–g). The C-1 unsubstituted 1,2-dihydroisoquinoline (7c) was found to be very unstable. In the case of the 5,6-dihydroisoquinolines (6h and 6i), reaction of potassium amide in liquid ammonia resulted in a mixture of 1-aminoisoquinoline (9) and the isoquinolines (8h and 8i). All the above compounds have been characterised by spectral data. A probable pathway for the formation of the 1,2-dihydroisoquinolines (7a–g) and the isoquinolines (8a–i) is suggested.

Editorial of "International Journal of Critical Indigenous Studies Volume 2, Number 1, 2009"

Over the past two decades neo liberalism has shaped global economic activity. The international reach of the current economic crisis propelled by the subprime mortgage meltdown in the United States has affected Indigenous communities in different ways to those whose investments were depleted by the Wall Street activities of an unregulated corporate and banking sector. Throughout this roller coaster economic ride the low socio-economic position of Indigenous peoples continued in Canada, the United States of America, New Zealand, Hawaii and Australia. The logic, or illogic of capital, failed to extend the boom of the economic upturn to Indigenous peoples, but is poised to extend the repercussions of the current downturn deep into Indigenous lives. The consistency of the Indigenous socio-economic position across these countries, even where treaties exist, indicates that the phenomenon is based on a shared Indigenous reality. In this special edition, the commonality in the way in which Indigenous people are engaged in and positioned by market forces and regulation by their respective nation states is proposed as one of the foundation plates of that Indigenous positioning...

4-Biphenylyl phenyl thioketone (I), C19H14S, and 1-naphthyl phenyl thioketone (II), C17H12S

(I): Mr=274"39, orthorhombic, Pbca, a = 7.443 (1), b= 32.691 (3), c= 11.828 (2)A, V= 2877.98A 3, Z=8, Din= 1.216 (flotation in KI), D x = 1.266 g cm -3, /~(Cu Ka, 2 = 1.5418 A) = 17.55 cm -1, F(000) = li52.0, T= 293 K, R = 6.8%, 1378 significant reflections. (II): M r = 248.35, orthorhombic, P212~21, a = 5.873 (3), b = 13.677 (3), c = 15-668 (5) A, V = 1260.14 A 3, Z = 4, D,n = 1.297 (flotation in KI), Dx= 1.308 g cm -a, /t(CuKa, 2=1.5418 A) = 19.55 cm -~, F(000) = 520.0, T= 293 K, R = 6.9%, 751 significant reflections. Crystals of (I) and (II) undergo photo-oxidation in the crystallinestate. In (I) the dihedral angle between the phenyl rings of the biphenyl moiety is 46 (1) °. The C=S bond length is 1.611(5) A in (I) and 1.630 (9)/~ in (II). The correlation between molecular packing and reactivity is discussed.

Editorial of "International Journal of Critical Indigenous Studies Volume 3, Number 1, 2010"

The articles in this edition of the International Journal of Critical Indigenous Studies engage collectively with how different epistemologies and cultural values inform power relations in different locations, situations and contemporary contexts. As a group, these articles demonstrate, over varying facets, how meaning, communicative intent and interpretive effect are constitutive of power relations between Indigenous people and non Indigenous people. Jackie Grey discusses the labour of belonging as played out in a dispute over Indigenous fishing rights in a small New England town of Aquinnah, located on Noepe Island the traditional lands of the Wampanoag in the United States of America. She reveals the ways in which the jurisdiction of non Indigenous belonging operates discursively and materially to preclude Indigenous rights and self determination. Grey's analysis highlights the incommensurability of Indigenous and non Indigenous belonging that are played out in power relations born of colonisation.