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Selected AbstractsThe anatomy of the palatoquadrate in the Lower Triassic Proterosuchus fergusi (Reptilia, Archosauromorpha) and its morphological transformation within the archosauriform cladeACTA ZOOLOGICA, Issue 3 2009Jozef Klembara Abstract The anatomy of the palatoquadrate ossifications of the Lower Triassic archosauromorph Proterosuchus fergusi from South Africa is described. It consists of two ossifications, the epipterygoid and the quadrate, which were joined by cartilage in life. The margins of the cartilage are clearly indicated by ridges and grooves on the dorsal surface of the pterygoid. The epipterygoid ossification consists of two structures: the anteroposteriorly expanded basal portion and, dorsally from it, an extending, slender, ascending process. From the anterior margin of the basal portion of the epipterygoid, a plate-like structure, herein called the lamina epipterygoidea anteromedialis, extends anteromedially to form the anterolateral wall of the cavum epiptericum. Comparisons with the similarly constructed embryonal and adult epipterygoid components of Sphenodon punctatus show that the anteromedial lamina of the epipterygoid of P. fergusi is an additional component of the epipterygoid of this species and that this lamina is absent in the former species. However, a structure in a topologically similar position to the anteromedial lamina of the epipterygoid of P. fergusi is present in the palatoquadrate of Alligator mississippiensis. In the latter species, the structure is called the lamina palatoquadrati anterior; it ossifies in membrane and forms the dorsolateral cover of the huge trigeminal ganglion. It is hypothesized here that the anteromedial lamina of the epipterygoid of P. fergusi and the anterior lamina of the palatoquadrate of A. mississippiensis are most probably homologous structures and are present in both the basal and one of the crown taxa of the archosauromorph clade, respectively. [source] Robert Southey, Lord Macaulay and the Standard of Living ControversyHISTORY, Issue 284 2001W. A. Speck The early nineteenth century witnessed gladiatorial contests in print between the contributors to the conservative Quarterly Review and the radical Edinburgh Review. Among the chief protagonists of the two papers were Robert Southey, leading contributor to the Quarterly from its launch in 1809 until 1839, and Thomas Babington Macaulay, whose first contribution to the Edinburgh, on ,Milton', appeared in August 1825, after which he became a mainstay of the periodical. Their ,reviews' were long essays of 10,000 or more words, in which the works purportedly being reviewed were mere pegs on which to hang their own observations. They were generally scathing about publications which took an ideological stance opposite to their own, and sympathetic to those which adopted a similar position to that which they held. Though they frequently made barbed references to each other in their reviews, Southey never reviewed a work by Macaulay, who only once criticized one by his rival. Nevertheless, that particular occasion, in January 1830, was a classic clash of Titans. It demonstrated their fundamental disagreement over the prospects facing society from the initial impact of the industrial revolution. [source] Photoreceptive organs in larvae of Spionidae (Annelida) and SipunculaJOURNAL OF ZOOLOGY, Issue 4 2006V. I. Radashevsky Abstract A pair of spherical unpigmented ocelli in addition to pigmented eyes have been observed in the anterior part of the prostomium in larvae of more than 40 species of Spionidae examined alive with light microscopy. Ocelli become visible in larvae at the one- to three-segment stage, increase in size as growth proceeds, and probably disintegrate in the course of metamorphosis because they were not observed in adults and settled juveniles. One pair of transparent, spherical bodies is also found in the anterior part of the head of planktotrophic pelagosphera larvae of Sipuncula. These bodies are in a similar position and have a similar appearance and size to unpigmented ocelli in Spionidae larvae. A pair of epidermal invaginations, densely covered with short cilia, is also observed antero-laterally in the head in pelagospheras of one species. These invaginations appear similar to the nuchal organs present in many polychaete larvae. Photoreceptive organs so far reported for sipunculan larvae comprise only pigmented eyes. Unpigmented ocelli and nuchal organs have never been reported in pelagospheras. Further ultrastructural investigations on sipunculan larvae are encouraged to clarify the composition, function and morphogenesis of transparent, spherical bodies and ciliated invaginations in the anterior part of the head. Such investigations may help to better understand the nature of photoreceptive structures and nuchal organs in Sipuncula, and also contribute to phylogenetic hypotheses regarding relationships of the Sipuncula and Annelida. [source] OH megamasers, starburst and AGN activity in Markarian 231MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2005A. M. S. Richards ABSTRACT We present Multi-Element Radio-Linked Interferometer Network (MERLIN) observations of OH maser and radio continuum emission within a few hundred pc of the core of the ultraluminous infrared galaxy (ULIRG) Markarian 231. This is the only known OH megamaser galaxy classed as a Seyfert 1. Maser emission is identified with the 1665- and 1667-MHz transitions over a velocity extent of 720 km s,1. Both lines show a similar position,velocity structure including a gradient of 1.7 km s,1 pc,1 from NW to SE along the 420-pc major axis. The (unresolved) inner few tens of pc possess a much steeper velocity gradient. The maser distribution is modelled as a torus rotating about an axis inclined at ,45° to the plane of the sky. We estimate the enclosed mass density to be 320 ± 90 M, pc,3 in a flattened distribution. This includes a central unresolved mass of ,8 × 106 M,. All the maser emission is projected against a region with a radio continuum brightness temperature ,105 K, giving a maser gain of ,2.2. The 1667:1665 MHz line ratio is close to 1.8 (the value predicted for thermal emission) consistent with radiatively pumped, unsaturated masers. This behaviour and the kinematics of the torus suggest that the size of individual masing regions is in the range 0.25,4 pc with a covering factor close to unity. There are no very bright compact masers, in contrast to galaxies such as the Seyfert 2 Markarian 273, where the masing torus is viewed nearer edge-on. The comparatively modest maser amplification seen from Markarian 231 is consistent with its classification in the unification scheme for Seyfert galaxies. Most of the radio continuum emission on 50,500 pc scales is probably of starburst origin but the compact peak is 0.4 per cent polarized by a magnetic field running north,south, similar to the jet direction on these scales. There is no close correlation between maser and continuum intensity, suggesting that much of the radio continuum must originate in the foreground and indeed the relative continuum brightness is slightly greater in the direction of the approaching jet. Comparisons with other data show that the jet changes direction close the nucleus and suggest that the sub-kpc disc hosting the masers and starburst activity is severely warped. [source] Hemoglobin Kenya composed of ,- and (A,,)-fusion-globin chains, associated with hereditary persistence of fetal hemoglobinAMERICAN JOURNAL OF HEMATOLOGY, Issue 1 2009Ibifiri Wilcox Hb Kenya is made up of two normal ,-globin chains and two A,,-fusion globin chains. The latter are the product of an A,,-hybrid globin gene formed as a result of misalignment during meiosis and nonhomologous crossing over. It is associated with a deletion of 22.7 kb including the ,-globin gene, between the A,- and ,-globin genes. Hb Kenya is found in Kenyans and Ugandans. Heterozygotes have moderately increased Hb F, and this mutation has been known as an (A,,)+ hereditary persistence of fetal hemoglobin (HPFH). Compound heterozygotes for Hb Kenya/Hb S are thought to be asymptomatic, but reports of long term follow-up of these patients are lacking. The correct identification of Hb Kenya is sometimes problematic. In cation exchange high performance liquid chromatography, Hb Kenya elutes in similar position as Hb A2, Hb Lepore, Hb E, and several other variant hemoglobins. Definitive diagnosis that is necessary for proper patient management is best done by DNA-based gap-PCR tests. Am. J. Hematol, 2009. © 2008 Wiley-Liss, Inc. [source] Crystal structure reveals two alternative conformations in the active site of ribonuclease Sa2ACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2004Jozef Three different strains of Streptomyces aureofaciens produce the homologous ribonucleases Sa, Sa2 and Sa3. The crystal structures of ribonuclease Sa (RNase Sa) and its complexes with mononucleotides have previously been reported at high resolution. Here, the structures of two crystal forms (I and II) of ribonuclease Sa2 (RNase Sa2) are presented at 1.8 and 1.5 Å resolution. The structures were determined by molecular replacement using the coordinates of RNase Sa as a search model and were refined to R factors of 17.5 and 15.0% and Rfree factors of 21.8 and 17.2%, respectively. The asymmetric unit of crystal form I contains three enzyme molecules, two of which have similar structures to those seen for ribonuclease Sa, with Tyr87 at the bottom of their active sites. In the third molecule, Tyr87 has moved substantially: the CA atom moves almost 5,Å and the OH of the side chain moves 10,Å, inserting itself into the active site of a neighbouring molecule at a similar position to that observed for the nucleotide base in RNase Sa complexes. The asymmetric unit of crystal form II contains two Sa2 molecules, both of which are similar to the usual Sa structures. In one molecule, two main-chain conformations were modelled in the ,-helix. Finally, a brief comparison is made between the conformations of the Sa2 molecules and those of 34 independent molecules taken from 20 structures of ribonuclease Sa and two independent molecules taken from two structures of ribonuclease Sa3 in various crystal forms. [source] The Role and Functions of Audit Committees in the Indian Corporate Governance: Empirical FindingsINTERNATIONAL JOURNAL OF AUDITING, Issue 1 2004Jawaher Al-Mudhaki This paper examines the composition, focus and functions of audit committees (ACs), the effects of meetings and the criteria used in the selection of members by Indian listed companies from 73 questionnaire responses. The survey was carried out during February,March, 2002. The study reveals that so far only 56.2% of companies have established an AC despite the fact that it is now mandatory. Of those companies which have ACs, 68.3% have between three and six members on ACs. However, only 14.6% of companies have independent non-executive directors on the committee, while 90.2% have non-executive directors. This shows a lack of independent representation on the committees. The functions of ACs are quite diverse and are classified in three areas: financial statements and reporting, audit planning, and internal control and evaluation. The review of annual audited financial statements, discussion and recommendations of audit fees and review of the effectiveness of internal control were rated very highly by the respondents. The review of note disclosure and scope of external audit work are other important functions performed by ACs. The most important areas for focus are compliance with the standards and regulatory bodies, probing material items and undisclosed liabilities. However, there are statistical differences between medium and large sized companies in the performance of their role. The main criteria used for membership of an AC are: experience and knowledge of business, experience of holding similar positions and accounting and finance expertise. Ownership in the company was not perceived as an important criterion. The majority of companies' AC meetings are held monthly or quarterly. MANOVA analysis reveals that the frequency of AC meetings has an effect on the internal control functions. The study concludes that the concept of an AC is not new in India but their formation is slow and their composition lacks independence. AC functions are still concentrated in the traditional areas of accounting and their role is not changing fast enough to make the corporate governance more effective. [source] TOP: a new method for protein structure comparisons and similarity searchesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2000Guoguang Lu In order to facilitate the three-dimensional structure comparison of proteins, software for making comparisons and searching for similarities to protein structures in databases has been developed. The program identifies the residues that share similar positions of both main-chain and side-chain atoms between two proteins. The unique functions of the software also include database processing via Internet- and Web-based servers for different types of users. The developed method and its friendly user interface copes with many of the problems that frequently occur in protein structure comparisons, such as detecting structurally equivalent residues, misalignment caused by coincident match of C, atoms, circular sequence permutations, tedious repetition of access, maintenance of the most recent database, and inconvenience of user interface. The program is also designed to cooperate with other tools in structural bioinformatics, such as the 3DB Browser software [Prilusky (1998). Protein Data Bank Q. Newslett.84, 3,4] and the SCOP database [Murzin, Brenner, Hubbard & Chothia (1995). J. Mol. Biol.247, 536,540], for convenient molecular modelling and protein structure analysis. A similarity ranking score of `structure diversity' is proposed in order to estimate the evolutionary distance between proteins based on the comparisons of their three-dimensional structures. The function of the program has been utilized as a part of an automated program for multiple protein structure alignment. In this paper, the algorithm of the program and results of systematic tests are presented and discussed. [source] Seeking a Holocene drift ice proxy: non-clay mineral variations from the SW to N-central Iceland shelf: trends, regime shifts, and periodicities,JOURNAL OF QUATERNARY SCIENCE, Issue 7 2009John T. Andrews Abstract Quantitative X-ray diffraction analysis of the <2,mm sediment fraction was carried out on 1257 samples (from the seafloor and 16 cores) from the Iceland shelf west of 18° W. All but one core (B997-347PC) were from transects along troughs on the NW to N-central shelf, an area that in modern and historic times has been affected by drift ice. The paper focuses on the non-clay mineralogy of the sediments (excluding calcite and volcanic glass). Quartz and potassium feldspars occupy similar positions in an R-mode principal component analysis, and oligoclase feldspar tracks quartz; these minerals are used as a proxy for ice-rafted detritus (IRD). Accordingly, the sum of these largely foreign minerals (Q&K) (to Icelandic bedrock) is used as a proxy for drift ice. A stacked, equi-spaced 100 a record is developed which shows both low-frequency trends and higher-frequency events. The detrended stacked record compares well with the flux of quartz (mg,cm,2,a,1) at MD99-2269 off N Iceland. The multi-taper method indicated that there are three significant frequencies at the 95% confidence level with periods of ca. 2500, 445 and 304 a. Regime shift analysis pinpoints intervals when there was a statistically significant shift in the average Q&K weight %, and identifies four IRD-rich events separated by intervals with lower inputs. There is some association between peaks of IRD input, less dense surface waters (from ,18O data on planktonic foraminifera) and intervals of moraine building. Copyright © 2009 John Wiley & Sons, Ltd. [source] Potential population-based electronic data sources for rapid pandemic influenza vaccine adverse event detection: a survey of health plans,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 12 2008Kristen M. Moore MPH Abstract Purpose A vaccine against pandemic influenza may be rapidly and widely distributed, and could be used in populations with little prior exposure to influenza vaccines. Under such conditions, it will be important to gain timely information about the rates of vaccine adverse events, ideally by using electronic data from large populations. Many public and private health plans and payers have such information. Methods Between May and September 2007, we conducted a decision maker interview and technical assessment with several health plans in the United States. The interview and survey evaluated technical capability, organizational capacity, and willingness to participate in a coordinated program of rapid safety research targeting pandemic and other influenza vaccines. Results Eleven health plans (eight private, three public) participated in the decision maker interview. Most interviewees were medical directors or held similar positions within their organizations. Participating plans provided coverage and/or care for approximately 150 million members in the U.S. Nine health plans completed a technical assessment survey. Most decision makers indicated interest and willingness to participate in a coordinated rapid safety surveillance program, and all reported the necessary claims data analysis experience. Respondents noted legal, procedural, budgetary, and technical barriers to participation. Conclusions Senior decision makers representing private and public health plans were willing and asserted the ability of their organizations to participate in pandemic influenza vaccine safety monitoring. Developing working relationships, negotiating contracts, and obtaining necessary regulatory and legal approvals were identified as key barriers. These findings may be generalizable to other vaccines and pharmaceutical products. Copyright © 2008 John Wiley & Sons, Ltd. [source] Unequal Pay: The Role of GenderPUBLIC ADMINISTRATION REVIEW, Issue 6 2006Mohamad G. Alkadry Pay disparities between men and women persist in the U.S. workforce despite comparable pay legislation, advocacy, and social change. This article discusses theories of gender pay disparities, such as the glass ceiling, position segregation, agency segregation, and human capital. Using an online national survey, 1,600 responses were collected for four groups of public procurement professionals. The gender wage gap ranged from $5,035 to $9,577. Multiple regression of the data show that gender continues to play a major role in predicting the salaries of public officials in similar positions. Gender and human capital variables predicted between 36.5 percent and 53.9 percent of the variance in pay. [source] New pseudopolymorphs of 5-fluorocytosineACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2009Maya Tutughamiarso In order to better understand the interaction between the pharmaceutically active compound 5-fluorocytosine [4-amino-5-fluoropyrimidin-2(1H)-one] and its receptor, hydrogen-bonded complexes with structurally similar bonding patterns have been investigated. During the cocrystallization screening, three new pseudopolymorphs of 5-fluorocytosine were obtained, namely 5-fluorocytosine dimethyl sulfoxide solvate, C4H4FN3O·C2H6OS, (I), 5-fluorocytosine dimethylacetamide hemisolvate, C4H4FN3O·0.5C4H9NO, (II), and 5-fluorocytosine hemihydrate, C4H4FN3O·0.5H2O, (III). Similar hydrogen-bond patterns are observed in all three crystal structures. The 5-fluorocytosine molecules form ribbons with repeated R22(8) dimer interactions. These dimers are stabilized by N,H...N and N,H...O hydrogen bonds. The solvent molecules adopt similar positions with respect to 5-fluorocytosine. Depending on the hydrogen bonds formed by the solvent, the 5-fluorocytosine ribbons form layers or tubes. A database study was carried out to compare the hydrogen-bond pattern of compounds (I),(III) with those of other (pseudo)polymorphs of 5-fluorocytosine. [source] A polymorph of tetrakis(acetonitrile-,N)copper(I) tetrafluoridoborateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Jan W. Bats A P212121 polymorph of the title compound, [Cu(CH3CN)4]BF4, is reported. The crystal structure is very similar to the structure of the Pna21 polymorph reported by Jones & Crespo [Acta Cryst. (1998), C54, 18,20]. The anions and one of the three independent cations occupy similar positions in both polymorphs. Two of the four symmetry-related positions of the other two cations are also identical in the two polymorphs, and the other two positions are related by mirror symmetry. The crystal used for the structure determination contained a volume fraction of 0.088,(7) of the Pna21 polymorph. [source] High-resolution structure of the native histone octamerACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2005Christopher M. Wood Crystals of native histone octamers (H2A,H2B),(H4,H3),(H3,,H4,),(H2B,,H2A,) from chick erythrocytes in 2,M KCl, 1.35,M potassium phosphate pH 6.9 diffract X-rays to 1.90,Å resolution, yielding a structure with an Rwork value of 18.7% and an Rfree of 22.2%. The crystal space group is P65, the asymmetric unit of which contains one complete octamer. This high-resolution model of the histone-core octamer allows further insight into intermolecular interactions, including water molecules, that dock the histone dimers to the tetramer in the nucleosome-core particle and have relevance to nucleosome remodelling. The three key areas analysed are the H2A,,H3,H4 molecular cluster (also H2A,H3,,H4,), the H4,H2B, interaction (also H4,,H2B) and the H2A,,H4 ,-sheet interaction (also H2A,H4,). The latter of these three regions is important to nucleosome remodelling by RNA polymerase II, as it is shown to be a likely core-histone binding site, and its disruption creates an instability in the nucleosome-core particle. A majority of the water molecules in the high-resolution octamer have positions that correlate to similar positions in the high-resolution nucleosome-core particle structure, suggesting that the high-resolution octamer model can be used for comparative studies with the high-resolution nucleosome-core particle. [source] | ||||||||||||||||||||||