29 resultados para Bayezid I, Sultan of the Turks, ca. 1360-1403.
em University of Queensland eSpace - Australia
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Purpose, An integrated ionic mobility-pore model for epidermal iontophoresis is developed from theoretical considerations using both the free volume and pore restriction forms of the model for a range of solute radii (r(j)) approaching the pore radii (r(p)) as well as approximation of the pore restriction form for r(j)/r(p) < 0.4. In this model, we defined the determinants for iontophoresis as solute size (defined by MV, MW or radius), solute mobility, solute shape, solute charge, the Debye layer thickness, total current applied, solute concentration, fraction ionized, presence of extraneous ions (defined by solvent conductivity), epidermal permselectivity, partitioning rates to account for interaction of unionized and ionized lipophilic solutes with the wall of the pore and electroosmosis. Methods, The ionic mobility-pore model was developed from theoretical considerations to include each of the determinants of iontophoretic transport. The model was then used to reexamine iontophoretic flux conductivity and iontophoretic flux-fraction ionized literature data on the determinants of iontophoretic flux. Results. The ionic mobility-pore model was found to be consistent with existing experimental data and determinants defining iontophoretic transport. However, the predicted effects of solute size on iontophoresis are more consistent with the pore-restriction than free volume form of the model. A reanalysis of iontophoretic flux-conductivity data confirmed the model's prediction that, in the absence of significant electroosmosis, the reciprocal of flux is linearly related to either donor or receptor solution conductivity. Significant interaction with the pore walls, as described by the model, accounted for the reported pH dependence of the iontophoretic transport for a range of ionizable solutes. Conclusions. The ionic mobility-pore iontophoretic model developed enables a range of determinants of iontophoresis to be described in a single unifying equation which recognises a range of determinants of iontophoretic flux.
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The Edinburgh-Cape Blue Object Survey is a major survey to discover blue stellar objects brighter than B similar to 18 in the southern sky. It is planned to cover an area of sky of 10 000 deg(2) with \b\ > 30 degrees and delta < 0 degrees. The blue stellar objects are selected by automatic techniques from U and B pairs of UK Schmidt Telescope plates scanned with the COSMOS measuring machine. Follow-up photometry and spectroscopy are being obtained with the SAAO telescopes to classify objects brighter than B = 16.5. This paper describes the survey, the techniques used to extract the blue stellar objects, the photometric methods and accuracy, the spectroscopic classification, and the limits and completeness of the survey.
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We present the results of Australia Telescope Compact Array (ATCA) H i line and 20-cm radio continuum observations of the galaxy quartet NGC 6845. The H i emission extends over all four galaxies but can only be associated clearly with the two spiral galaxies, NGC 6845A and B, which show signs of strong tidal interaction. We derive a total H i mass of at least 1.8 x 10(10) M-., most of which is associated with NGC 6845A, the largest galaxy of the group. We investigate the tidal interaction between NGC 6845A and B by studying the kinematics of distinct H i components and their relation to the known H ii regions. No H i emission is detected from the two lenticular galaxies, NGC 6845C and D. A previously uncatalogued dwarf galaxy, ATCA J2001-4659, was detected 4.4 arcmin NE from NGC 6845B and has an H i mass of similar to5 x 10(8) M-.. No H i bridge is visible between the group and its newly detected companion. Extended 20-cm radio continuum emission is detected in NGC 6845A and B as well as in the tidal bridge between the two galaxies. We derive star formation rates of 15-40 M-. yr(-1).
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There has been much argument about the phylogenetic relationships of the four suborders of lice (Insecta: Phthiraptera). Lyal's study of the morphology of lice indicated that chewing/biting lice (Mallophaga) are paraphyletic with respect to sucking lice (Anoplura). To test this hypothesis we inferred the phylogeny of 33 species of lice from small subunit (SSU) rRNA sequences (18S rRNA). Liposcelis sp. from the Liposcelididae (Psocoptera) was used for outgroup reference. Phylogenetic relationships among the four suborders of lice inferred from these sequences were the same as those inferred from morphology. The Amblycera is apparently the sister-group to all other lice whereas the Rhynchophthirina is apparently sister to the Anoplura; these two suborders are sister to the Ischnocera, i.e. (Amblycera (Ischnocera (Anoplura, Rhynchophthirina))). Thus, the Mallophaga (Amblycera, Ischnocera, Rhynchophthirina) is apparently paraphyletic with respect to the Anoplura. Our analyses also provide evidence that: (i) each of the three suborders of lice that are well represented in our study (the Amblycera, Ischnocera, and Anoplura) are monophyletic; (ii) the Boopiidae is monophyletic; (iii) the genera Heterodoxus and Latumcephalum (Boopiidae) are more closely related to one another than either is to the genus Boopia (also Boopiidae); (iv) the Ricinidae and Laemobothridae may be sister-taxa; (v) the Philopteridae may be paraphyletic with respect to the Trichodectidae; (vi) the genera Pediculus and Pthirus are more closely related to each other than either is to the genus Pedicinus ; and (vii) in contrast to published data for mitochondrial genes, the rates of nucleotide substitution in the SSU rRNA of lice are not higher than those of other insects, nor do substitution rates in the suborders differ substantially from one another.
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ATCA H I and radio continuum observations of the peculiar southern galaxy IC 2554 and its surroundings reveal typical signatures of an interacting galaxy group. We detected a large H I cloud between IC 2554 and the elliptical galaxy NGC 3136B. The gas dynamics in IC 2554 itself, which is sometimes described as a colliding pair, are surprisingly regular, whereas NGC 3136B was not detected. The H I cloud, which emerges from IC 2554 as a large arc-shaped plume, has a size of similar to30 kpc, larger than that of IC 2554. The total H I mass of the IC 2554 system is similar to2 x 10(9) M., one-third of which resides in the H I cloud. It is possible that tidal interaction between IC 2554 and NGC 3136B caused this spectacular H I cloud, but the possibility of IC 2554 being a merger remnant is also discussed. We also detected H I gas in the nearby galaxies ESO 092-G009 and RKK 1959 and an associated H I cloud, ATCA J1006-6710. Together they have an H I mass of similar to4.6 x 10(8) M-.. Another new H I source, ATCA J1007-6659, with an H I mass of only similar to2.2 x 10(7) M. was detected roughly between IC 2554 and ESO 092-G009 and corresponds to a face-on low surface brightness dwarf galaxy. Star formation is evident only in the galaxy IC 2554 with a rate of similar to4 M. yr(-1).
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In this paper, we describe an algorithm that automatically detects and labels peaks I - VII of the normal, suprathreshold auditory brainstem response (ABR). The algorithm proceeds in three stages, with the option of a fourth: ( 1) all candidate peaks and troughs in the ABR waveform are identified using zero crossings of the first derivative, ( 2) peaks I - VII are identified from these candidate peaks based on their latency and morphology, ( 3) if required, peaks II and IV are identified as points of inflection using zero crossings of the second derivative and ( 4) interpeak troughs are identified before peak latencies and amplitudes are measured. The performance of the algorithm was estimated on a set of 240 normal ABR waveforms recorded using a stimulus intensity of 90 dBnHL. When compared to an expert audiologist, the algorithm correctly identified the major ABR peaks ( I, III and V) in 96 - 98% of the waveforms and the minor ABR peaks ( II, IV, VI and VII) in 45 - 83% of waveforms. Whilst peak II was correctly identified in only 83% and peak IV in 77% of waveforms, it was shown that 5% of the peak II identifications and 31% of the peak IV identifications came as a direct result of allowing these peaks to be found as points of inflection. Copyright (C) 2005 S. Karger AG, Basel.
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We present Ehrenfest relations for the high temperature stochastic Gross-Pitaevskii equation description of a trapped Bose gas, including the effect of growth noise and the energy cutoff. A condition for neglecting the cutoff terms in the Ehrenfest relations is found which is more stringent than the usual validity condition of the truncated Wigner or classical field method-that all modes are highly occupied. The condition requires a small overlap of the nonlinear interaction term with the lowest energy single particle state of the noncondensate band, and gives a means to constrain dynamical artefacts arising from the energy cutoff in numerical simulations. We apply the formalism to two simple test problems: (i) simulation of the Kohn mode oscillation for a trapped Bose gas at zero temperature, and (ii) computing the equilibrium properties of a finite temperature Bose gas within the classical field method. The examples indicate ways to control the effects of the cutoff, and that there is an optimal choice of plane wave basis for a given cutoff energy. This basis gives the best reproduction of the single particle spectrum, the condensate fraction and the position and momentum densities.
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The Iberian Pyrite Belt (IPB), which forms part of the Variscan orogenic massif, is renowned for the magnitude and extent of its massive sulfide mineralization. The stratigraphic record of the IPB consists of Upper Palaeozoic sedimentary and igneous rocks. In ascending order, these comprise the thick Phyllite-Quartzite Group attributed to the Middle and Upper Devonian and characterized by shales and quartzites with conglomeratic and carbonate intercalations towards the top; the appreciably thinner Volcano-Sedimentary Complex, a heterogeneous uppermost Devonian-Mississippian unit embodying diverse volcanic, subvolcanic, and sedimentary rocks that host the massive sulfide deposits; and the shaly and sandy, turbiditic Culm Group (Carboniferous). This entire succession was folded and faulted during the Asturian phase of the Variscan Orogeny that gave rise to a thin-skinned type structure. The present study constitutes a detailed blostratigraphic investigation of palynologically productive samples representative of the Phyllite-Quartzite Group and the basal (anoxic) portion of the Volcano-Sedimentary Complex. These were collected from surface and mine exposures variously located in the Spanish part of the IPB; out of 282 samples processed, 117 proved to be productive palynologically. The aim of this project is to provide comprehensive palynostratigraphic data applicable to precise dating and correlation of the IPB's stratigraphic succession (i.e., of the two sampled lithostratigraphic units), which has hitherto been investigated biostratigraphically on a relatively localized basis. The results are incorporated in two successive parts. The first of these, i. e., the present paper, focuses on the systematic analysis of the terrestrial (miospore) component of the palynological assemblages. The second part, devoted to the marine, organic-walled microphytoplankton (acritarchs and prasinophytes), will evaluate the stratigraphic significance of the IPB palynofloras and their application to elucidating the geological history of the region. In the systematic-descriptive section, which occupies the bulk of this paper, 55 species of trilete miospores are described and are allocated among 34 genera, two of which (Cristicavatispora and Epigruspora) are newly instituted herein. The majority of the species are either positively identifiable or closely affiliable with previously named species. The nine newly established species are as follows: Camptozonotriletes confertus, Indotriradites diversispinosus, Cristicavatispora dispersa (type species), Epigruspora regularis (type species), Ancyrospora? implicata, Endosporites tuberosus, Rugospora explicata, Spelaeotriletes plicatus, and Teichertospora iberica.
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Familial hyperaldosteronism type II (FH-II) is characterized by autosomal dominant inheritance and hypersecretion of aldosterone due to adrenocortical hyperplasia or an aldosterone-producing adenoma; unlike FH type I (FH-I), hyperaldosteronism in FH-II is not suppressible by dexamethasone. Of a total of 17 FH-II families with 44 affected members, we studied a large kindred with 7 affected members that was informative for linkage analysis. Family members were screened with the aldosterone/PRA ratio test; patients with aldosterone/PRA ratio greater than 25 underwent fludrocortisone/salt suppression testing for confirmation of autonomous aldosterone secretion. Postural testing, adrenal gland imaging, and adrenal venous sampling were also performed. Individuals affected by FH-II demonstrated lack of suppression of plasma A levels after 4 days of dexamethasone treatment (0.5 mg every 6 h). All patients had neg ative genetic testing for the defect associated with FH-I, the CYP11B1/CYP11B2 hybrid gene. Genetic linkage was then examined between FH-II and aldosterone synthase (the CYP11B2 gene) on chromosome 8q. A polyadenylase repeat within the 5'-region of the CYP11B2 gene and 9 other markers covering an approximately 80-centimorgan area on chromosome 8q21-8qtel were genotyped and analyzed for linkage. Two-point logarithm of odds scores were negative and ranged from -12.6 for the CYP11B2 polymorphic marker to -0.98 for the D8S527 marker at a recombination distance (theta) of 0. Multipoint logarithm of odds score analysis confirmed the exclusion of the chromosome 8q21-8qtel area as a region harboring the candidate gene for FH-II in this family. We conclude that FH-II shares autosomal dominant inheritance and hyperaldosteronism with FH-I, but, as demonstrated by the large kindred investigated in this report, it is clinically and genetically distinct. Linkage analysis demonstrated that the CYP11B2 gene is not responsible for FH-II in this family; furthermore, chromosome 8q21-8qtel most likely does not harbor the genetic defect in this kindred.
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Relative eye size, gross brain morphology and central localization of 2-[I-125]iodomelatonin binding sites and melatonin receptor gene expression were compared in six gadiform fish living at different depths in the north-east Atlantic Ocean: Phycis blennoides (capture depth range 265-1260 m), Nezumia aequalis (445-1512 m), Coryphaenoides rupestris (706-1932 m), Trachyrincus murrayi (1010-1884 m), Coryphaenoides guentheri (1030 m) and Coryphaenoides (Nematonurus) armatus (2172-4787 m). Amongst these, the eye size range was 0.15-0.35 of head length with a value of 0.19 for C.(N.) armatus, the deepest species. Brain morphology reflected behavioural differences with well-developed olfactory regions in P.blennoides, T.murrayi and C. (N.) armatus and evidence of olfactory deficit in N. aequalis, C. rupestris and C. guentheri. All species had a clearly defined optic tectum with 2-[I-125] iodomelatonin binding and melatonin receptor gene expression localized to specific brain regions in a similar pattern to that found in shallow-water fish. Melatonin receptors were found throughout the visual structures of the brains of all species. Despite living beyond the depth of penetration of solar light these fish have retained central features associated with the coupling of cycles of growth, behaviour and reproduction to the diel light-dark cycle. How this functions in the deep sea remains enigmatic.
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Within steroid receptor heterocomplexes the large tetraticopeptide repeat-containing immunophilins, cyclophilin 40 (CyP40), FKBP51, and FKBP52, target a common interaction site in heat shock protein 90 (HspSO) and act coordinately with HspSO to modulate receptor activity. The reversible nature of the interaction between the immunophilins and HspSO suggests that relative cellular abundance might be a key determinant of the immunophilin component within steroid receptor complexes. To investigate CyP40 gene regulation, we have isolated a fi-kilobase (kb) 5 ' -flanking region of the human gene and demonstrated that a similar to 50 base pair (bp) sequence adjacent to the transcription start site is essential for CyP40 basal expression. Three tandemly arranged Ets sites within this critical region were identified as binding elements for the multimeric Ets-related transcription factor, GA binding protein (GABP). Functional studies of this proximal promoter sequence, in combination with mutational analysis, confirmed these sites to be crucial for basal promoter function. Furthermore, overexpression of both GABP alpha and GABP beta subunits in Cos1 cells resulted in increased endogenous CyP40 mRNA levels. Significantly, a parallel increase in FKBP52 mRNA expression was not observed, highlighting an important difference in the mode of regulation of the CyP40 and FKBP52 genes. Our results identify GABP as a key regulator of CyP40 expression. GAFF is a common target of mitogen and stress-activated pathways and may integrate these diverse extracellular signals to regulate CyP40 gene expression.
The Las Campanas/AAT rich cluster survey - I. Precision and reliability of the photometric catalogue
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The Las Campanas Observatory and Anglo-Australian Telescope Rich Cluster Survey (LARCS) is a panoramic imaging and spectroscopic survey of an X-ray luminosity-selected sample of 21 clusters of galaxies at 0.07 < z < 0.16. Charge-coupled device (CCD) imaging was obtained in B and R of typically 2 degrees wide regions centred on the 21 clusters, and the galaxy sample selected from the imaging is being used for an on-going spectroscopic survey of the clusters with the 2dF spectrograph on the Anglo-Australian Telescope. This paper presents the reduction of the imaging data and the photometric analysis used in the survey. Based on an overlapping area of 12.3 deg(2) we compare the CCD-based LARCS catalogue with the photographic-based galaxy catalogue used for the input to the 2dF Galaxy Redshift Survey (2dFGRS) from the APM, to the completeness of the GRS/APM catalogue, b(J) = 19.45. This comparison confirms the reliability of the photometry across our mosaics and between the clusters in our survey. This comparison also provides useful information concerning the properties of the GRS/APM. The stellar contamination in the GRS/APM galaxy catalogue is confirmed as around 5-10 per cent, as originally estimated. However, using the superior sensitivity and spatial resolution in the LARCS survey evidence is found for four distinct populations of galaxies that are systematically omitted from the GRS/APM catalogue. The characteristics of the 'missing' galaxy populations are described, reasons for their absence examined and the impact they will have on the conclusions drawn from the 2dF Galaxy Redshift Survey are discussed.
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We report a prospective, randomized, multi-center, open-label 2-year trial of 81 postmenopausal women aged 53-79 years with at least one minimal-trauma vertebral fracture (VF) and low (T-score below 2) lumbar bone mineral density (BMD). Group HRT received piperazine estrone sulfate (PES) 0.625 - 1.25 mg/d +/- medroxyprogesterone acetate (MPA) 2.5 - 5 mg/d,- group HRT/D received HRT plus calcitriol 0.25 mug bd. All with a baseline dietary calcium (Ca) of < I g/d received Ca carbonate 0.6 g nocte. Final data were on 66 - 70 patients. On HRT/D, significant (P < 0.001) BNID increases from baseline by DXA were at total body - head, trochanter, Ward's, total hip, inter-trochanter and femoral shaft (% group mean Delta 4.2, 6.1, 9.3. 3.7. 3.3 and 3.3%, respectively). On HRT, at these significant Deltas were restricted to the trochanter and sites. si Wards. Significant advantages of HRT/D over HRT were in BMD of total body (- head), total hip and trochanter (all P = 0.01). The differences in mean Delta at these sites were 1.3, 2.6 and 3.9%. At the following, both groups Improved significantly -lumbar spine (AP and lateral), forearm shaft and ultradistal tibia/fibula. The weightbearing, site - specific benefits of the combination associated with significant suppression of parathyroid hormone-suggest a beneficial effect on cortical bone. Suppression of bone turnover was significantly greater on HRT/D (serum osteocalcin P = 0.024 and urinary hydroxyproline/creatinine ratio P = 0.035). There was no significant difference in the number of patients who developed fresh VFs during the trial (HRT 8/36, 22%; HRT/D 4/34, 12% - intention to treat); likewise in the number who developed incident nonvertebral fractures. This Is the first study comparing the 2 treatments in a fracture population. The results indicate a significant benefit of calcitriol combined with HRT on total body BMD and on BNID at the hip, the major site of osteoporotic fracture.
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Antigen recognition by cytotoxic CD8 T cells is dependent upon a number of critical steps in MHC class I antigen processing including proteosomal cleavage, TAP transport into the endoplasmic reticulum, and MHC class 1 binding. Based on extensive experimental data relating to each of these steps there is now the capacity to model individual antigen processing steps with a high degree of accuracy. This paper demonstrates the potential to bring together models of individual antigen processing steps, for example proteosome cleavage, TAP transport, and MHC binding, to build highly informative models of functional pathways. In particular, we demonstrate how an artificial neural network model of TAP transport was used to mine a HLA-binding database so as to identify H LA-binding peptides transported by TAP. This integrated model of antigen processing provided the unique insight that HLA class I alleles apparently constitute two separate classes: those that are TAP-efficient for peptide loading (HLA-B27, -A3, and -A24) and those that are TAP-inefficient (HLA-A2, -B7, and -B8). Hence, using this integrated model we were able to generate novel hypotheses regarding antigen processing, and these hypotheses are now capable of being tested experimentally. This model confirms the feasibility of constructing a virtual immune system, whereby each additional step in antigen processing is incorporated into a single modular model. Accurate models of antigen processing have implications for the study of basic immunology as well as for the design of peptide-based vaccines and other immunotherapies. (C) 2004 Elsevier Inc. All rights reserved.
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The class II major histocompatibility complex molecule I-A(g7) is strongly linked to the development of spontaneous insulin-dependent diabetes mellitus (IDDM) in non obese diabetic mice and to the induction of experimental allergic encephalomyelitis in Biozzi AB/H mice. Structurally, it resembles the HLA-DQ molecules associated with human IDDM, in having a non-Asp residue at position 57 in its beta chain. To identify the requirements for peptide binding to I-A(g7) and thereby potentially pathogenic T cell epitopes, we analyzed a known I-A(g7)-restricted T cell epitope, hen egg white lysozyme (HEL) amino acids 9-27. NH2- and COOH-terminal truncations demonstrated that the minimal epitope for activation of the T cell hybridoma 2D12.1 was M12-R21 and the minimum sequence for direct binding to purified I-A(g7) M12-Y20/K13-R21. Alanine (A) scanning revealed two primary anchors for binding at relative positions (p) 6 (L) and 9 (Y) in the HEL epitope. The critical role of both anchors was demonstrated by incorporating L and Y in poly(A) backbones at the same relative positions as in the HEL epitope. Well-tolerated, weakly tolerated, and nontolerated residues were identified by analyzing the binding of peptides containing multiple substitutions at individual positions. Optimally, p6 was a large, hydrophobic residue (L, I, V, M), whereas p9 was aromatic and hydrophobic (Y or F) or positively charged (K, R). Specific residues were not tolerated at these and some other positions. A motif for binding to I-A(g7) deduced from analysis of the model HEL epitope was present in 27/30 (90%) of peptides reported to be I-A(g7)-restricted T cell epitopes or eluted from I-A(g7). Scanning a set of overlapping peptides encompassing human proinsulin revealed the motif in 6/6 good binders (sensitivity = 100%) and 4/13 weak or non-binders (specificity = 70%). This motif should facilitate identification of autoantigenic epitopes relevant to the pathogenesis and immunotherapy of IDDM.