A biphasic response to adenosine in the coronary vasculature of the K+-arrested perfused rat heart

Biphasic vasodilatory responses to adenosine and 5'-N-ethylcarboxamidoadenosine (NECA) were observed in the coronary vasculature of K(+)-arrested perfused rat hearts. Dose-response data for both agonists were best represented by two-site models. For adenosine, two sites with negative log ED50 (pED50) values of 8.1 +/- 0.1 (mean +/- S.E.M) and 5.2 +/- 0.1 were obtained, mediating 31 +/- 2% and 69 +/- 2% of the total response. In the presence of 8-phenyltheophylline, the vasodilatory response to adenosine remained best fitted to a two-site model with pED50 values of 7.0 +/- 0.2 and 5.4 +/- 0.2. The relative contribution of each site to the total response remained unchanged. For NECA, pED50 values of 9.6 +/- 0.1 and 6.8 +/- 0.2 were obtained, representing 48 +/- 3% and 52 +/- 3% of the sites, respectively. In contrast, ATP produced a monophasic response with a pED50 value of 8.8 +/- 0.1. These results provide evidence of adenosine receptor and response heterogeneity in the in situ coronary vasculature.

Understanding past climate variation and environmental change for the future of an iconic landscape – K'gari Fraser Island, Queensland, Australia

The unique combination of landscapes and processes that are present and operate on Fraser Island (K'gari) create a dynamic setting that is capable of recording past environmental events, climate variations and former landscapes. Likewise, its geographic position makes Fraser Island sensitive to those events and processes. Based on optically stimulated luminescence dating, the records archived within the world's largest sand island span a period that has the potential to exceed 750 ka and contain specific records that are of extremely high resolution over the past 40,000 years. This is due to the geographic position of Fraser Island, which lies in the coastal subtropical region of Queensland Australia. Fraser Island is exposed to the open ocean currents of the Coral Sea on the east coast and the waters of Hervey Bay on its western margin and is positioned to receive moisture from the Indo-Australian monsoon, southeast trade winds and experiences occasional tropical and ex-tropical cyclones. We review literature that presents the current level of understanding of sea level change, ecological variation and environmental change on Fraser Island. The previous works illustrate the importance of Fraser Island and may link processes, environments and climates on Fraser Island with global records.

A novel serogenetic approach determines the community prevalence of celiac disease and informs improved diagnostic pathways

Background: Changing perspectives on the natural history of celiac disease (CD), new serology and genetic tests, and amended histological criteria for diagnosis cast doubt on past prevalence estimates for CD. We set out to establish a more accurate prevalence estimate for CD using a novel serogenetic approach.Methods: The human leukocyte antigen (HLA)-DQ genotype was determined in 356 patients with 'biopsy-confirmed' CD, and in two age-stratified, randomly selected community cohorts of 1,390 women and 1,158 men. Sera were screened for CD-specific serology.Results: Only five 'biopsy-confirmed' patients with CD did not possess the susceptibility alleles HLA-DQ2.5, DQ8, or DQ2.2, and four of these were misdiagnoses. HLA-DQ2.5, DQ8, or DQ2.2 was present in 56% of all women and men in the community cohorts. Transglutaminase (TG)-2 IgA and composite TG2/deamidated gliadin peptide (DGP) IgA/IgG were abnormal in 4.6% and 5.6%, respectively, of the community women and 6.9% and 6.9%, respectively, of the community men, but in the screen-positive group, only 71% and 75%, respectively, of women and 65% and 63%, respectively, of men possessed HLA-DQ2.5, DQ8, or DQ2.2. Medical review was possible for 41% of seropositive women and 50% of seropositive men, and led to biopsy-confirmed CD in 10 women (0.7%) and 6 men (0.5%), but based on relative risk for HLA-DQ2.5, DQ8, or DQ2.2 in all TG2 IgA or TG2/DGP IgA/IgG screen-positive subjects, CD affected 1.3% or 1.9%, respectively, of females and 1.3% or 1.2%, respectively, of men. Serogenetic data from these community cohorts indicated that testing screen positives for HLA-DQ, or carrying out HLA-DQ and further serology, could have reduced unnecessary gastroscopies due to false-positive serology by at least 40% and by over 70%, respectively.Conclusions: Screening with TG2 IgA serology and requiring biopsy confirmation caused the community prevalence of CD to be substantially underestimated. Testing for HLA-DQ genes and confirmatory serology could reduce the numbers of unnecessary gastroscopies. © 2013 Anderson et al.; licensee BioMed Central Ltd.

Activities in the $FeTiO_{3}-NiTiO_{3}$ Solid Solution from Alloy-Oxide Equilibria at 1273 K

Nine tie-lines between Fe-Ni alloys and FeTiO3-NiTiO3 solid solutions were determined at 1273 K. Samples were equilibrated in evacuated quartz ampoules for periods up to 10 days. Compositions of the alloy and oxide phases at equilibrium were determined by energy-dispersive x-ray spectroscopy. X-ray powder diffraction was used to confirm the results. Attainment of equilibrium was verified by the conventional tie-line rotation technique and by thermodynamic analysis of the results. The tie-lines are skewed toward the FeTiO3 corner. From the tie-line data and activities in the Fe-Ni alloy phase available in the literature, activities of FeTiO3 and NiTiO3 in the ilmenite solid solution were derived using the modified Gibbs-Duhem technique of Jacob and Jeffes [K.T. Jacob and J.H.E. Jeffes, An Improved Method for Calculating Activities from Distribution Equilibria, High Temp. High Press., 1972, 4, p 177-182]. The components of the oxide solid solution exhibit moderate positive deviations from Raoult's law. Within experimental error, excess Gibbs energy of mixing for the FeTiO3-NiTiO3 solid solution at 1273 K is a symmetric function of composition and can be represented as: Delta G(E) = 8590 (+/- 200) X-FeTiO3 X-NiTiO3 J/mol Full spectrum of tie-lines and oxygen potentials for the three-phase equilibrium involving Fe-Ni alloys, FeTiO3-NiTiO3 solid solutions, and TiO2 at 1273 K were computed using results obtained in this study and data available in the literature.

Transglutaminase-2 Regulation by Arecoline in Gingival Fibroblasts

Transglutaminase-2 (TGM-2) stabilizes extracellular matrix (ECM) proteins by cross-linking and has been implicated in several fibrotic disorders. Arecoline present in betel quid has been proposed as one of the causative factors for oral submucous fibrosis (OSMF). Hence, we hypothesize that arecoline may regulate TGM-2 and may have a role in the pathogenesis of OSMF. The expression of TGM-2 was studied in OSMF tissues by real-time RT-PCR analysis, and significant overexpression was observed in most OSMF tissues (P = 0.0112) compared with normal tissues. Arecoline induced TGM-2 mRNA and protein expression as well as TGM-2 activity in human gingival fibroblast cells. The addition of methocramine hemihydrate (M-2 muscarinic acetylcholine receptor selective antagonist) or 8'-bromo-cAMP abolished arecoline-mediated TGM-2 induction, suggesting a role for M-2 muscarinic acid receptor and a repressor role for cAMP. Our study provides evidence for TGM-2 overexpression in OSMF and its regulation by arecoline in oral fibroblasts.

Characterisation of k-Variegated Graphs, k greater-than-or-equal-to 3

A graph is said to be k-variegated if its vertex set can be partitioned into k equal parts such that each vertex is adjacent to exactly one vertex from every other part not containing it. Bednarek and Sanders [1] posed the problem of characterizing k-variegated graphs. V.N. Bhat-Nayak, S.A. Choudum and R.N. Naik [2] gave the characterization of 2-variegated graphs. In this paper we characterize k-variegated graphs for k greater-or-equal, slanted 3.

High-Pressure Low-Temperature Locknut Cell For Both Electron-Paramagnetic-Res And Nmr-Studies To 10 Kilobars And 77-K

A locked high-pressure cell with working pressure range up to 10 kbars suitable for low-temperature studies to 77 K has been described. It can be used for both EPR and NMR studies of single crystals (and other solid samples). The high-pressure seal and all other aspects of the cell remain the same for either application. Only a change of the bottom plug is required for a switch from a nuclear-magnetic-resonance (NMR) to an electron-paramagnetic-resonance (EPR) experiment. Details of the procedure for the calibration of pressure inside the cell at various temperatures are discussed. The performance of the cell in EPR (Cr3+ion) and NMR (27Al nucleus) studies is reported.

Konstrukcija mnimosti : K poètike "Voskovoj persony" Ju. Tynjanova

The subject of this work is the poetics of «The Wax Effigy», a short novel or novella by Jurii Tynianov, Russian writer, literary critic, historian of literature and prominent literary theoretician. The plot structure of the novel is based upon a real event, the creation by Bartolomeo Carlo Rastrelli in 1725 of a wax sculpture of the first Russian emperor, Peter the Great. «Construction of the Sham» consists of three chapters, an introduction and a conclusion. Due to the fact that Tynianov was at the same time a prose writer and theoretician of literature it seemed important to consider the reception of his prose and his works on literary theory in relationship to each other. The introduction is devoted to this task. The first chapter is about the history of the creation of the novel and its reception. Tynianov stopped writing one short story in order to write the novel; these two works have some common traits. It seems almost obvious that his work on the first text was a real step toward the creation of the second. In the first story there is an opposition of dead/alive which is semantic prefiguring of a central motif in «The Wax Effigy». An analysis of the reception of the novel demonstrated that almost every critic writing about the novel has described it as nonsense. Critics considered Tynianov's work in terms of «devices» and «content» and could not understand how devices are related to the content of the novel: the novel was thought as a signifier without any signified. Implicitly, critics thought the signified of the novel as a traditional one of the historical novel, as the historiosophical «idea», embodied in the system of literary devices. In this case literature becomes something instrumental, a kind of expression of extraliterary content. In contradistinction to that Tynianov considered literary semantics as an effect of the literary structure. From his point of view the literary sense is immanent to the process of signification accomplished inside the literary text. The second chapter is devoted to a rhetorical analysis of the opposition dead/alive. Tynianov systematically compares both terms of the opposition. As a result of this strategy the wax effigy of the dead emperor becomes «as if» alive and the world of living people «as if» dead. The qualifier «as if» refers to the fact that Tynianov creates an ambiguous semantic system. This rhetoric is related to European Romanticism and his «fantastic literature» (Merimé, Hoffmann, Maupassant etc.). But Tynianov demonstrates a linguistic origin of the strange fantoms created by romantics; he demystifies these idols by parodying the fantastic literature, that is, showing «how it was done». At the same time, the opposition mentioned above refers to his idea of «incongruity» which plays a prominent role in Tynianov s theory but has never been conceptualised. The incongruity is a inner collision of the literary text; from Tynianov's point of view the meaning of the work of literature is always a dynamic collision of semantically heterogeneous elements struggling with each other. In «The Wax Effigy» Tynianov creates a metalevel of the work demonstrating the process of creation of the literary sense. The third chapter is a reconstruction of Tynianov's conception of the historical prose, specifically of the mechanisms by which historical facts are transformed into literary events. Tynianov thought that the task of the historical novelist is to depict his hero as an actor, to demonstrate that as a wearer of many masks he is a creator of appearances, ambiguities. Here, in the «figure of fiction» (Andrei Belyi), the very idea of the historical prose and rhetoric employed in «The Wax Effigy», history and literature meet each other. In his last theoretical work, «On parody» Tynianov writes about the so-called sham structure of parody. In his opinion every parody is a text about other texts and «serious» work which could be read at the same time as a text about «reality». This twofold structure of parody is that of «The Wax Effigy»: that text speaks about ambiguities of the history and about ambiguities of the literary sense, about social reality of the past and - about the working of the literature itself. «The Wax Effigy» is written as a autoreflective text, as an experiment in literary semantics, as a system of literary ambiguities - of hero, rhetoric and the text itself. The meaning of the novel is created not by the embodiment extraliterary idea, but by the process of signification accomplished inside the work of literature. In this sense Tynianov's novel is parody, a break with the tradition of the historical novel preceding «The Wax Effigy».

Effects of Low Dose Irradiation on the K-Value and Hypoxanthine Concentration of Fish Fillets

Fillets of five fish species were irradiated at 0, 1 and 3kGy to investigate whether the K-value test of freshness can be applied to irradiated fish. Following irradiation, the fillets were stored on ice and sampled regularly for K-value analysis. Hypoxanthine (Hx) and total nucleotide content were also determined on fillets of two species. K-values of irradiated fillets were generally lower than those of unirradiated controls. Hypoxanthine levels paralleled the K-value changes. These results indicated that quality standards based on K-values or Hx levels that have been set for unirradiated species cannot be directly applied to fish that has been irradiated. Total nucleotide content did not appear to be affected by irradiation.

Spool valve mechanism used in a 20 K Gifford-McMahon cycle cryorefrigerator and its effect on the P-V diagram

The design and fabrication of a spool valve for a two-stage Gifford-McMahon cycle cryorefrigerator is described. The effect of this valve on the P-V diagram and practical methods of reducing the P-V degradation are also discussed.

Olen maa johon tahdot : Timo K. Mukan maailmankuvan poetiikkaa

The dissertation deals with the prose texts of the Finnish writer Timo K. Mukka, renowned for his depictions of his native Lapland. This research concerns the creation of world view in Mukka s prose, which is approached by studying what Mikhail Bakhtin calls generic change. Such genre change is the most characteristic feature of Mukka s prose. His prose is permeated with two genres in particular and changes between them: the ballad-like, archaistic and romantic prose-poem style and naturalistic, even grotesque expressions. In addition, these genres are associated with sublime and grotesque styles so that generic change tends to involve also stylistic changes in Mukka s prose. This study probes the tension-filled interrelationships between the ballad and naturalistic prose by examining the discourse of Mukka s characters. It is shown that these characters invariably find themselves in what Bakhtin calls the chronotope of the threshold; that is, the plots of Mukka s novels and short stories depict situations in which the characters are faced with decisions and deeds that will profoundly impact their lives. The discourse of the threshold affects the characters speech by filling it with dialogical dimensions. This makes their communication ethically loaded and polyphonic. This study is based on Mikhail Bakhtin s theory of the novel and international Bakhtin s studies. I also take into consideration the theoretical developments of Bakhtin s work; for example, the concept of ressentiment, adapted from the Bakhtin scholar Michel André Bernstein, plays an important role. In order to explicate on the psychology of Mukka s characters such as melancholy, abjection, sadism, and taboo I use the concepts familiar from Freudian psychoanalysis. The corpus of my research consists of the following texts: the long prose texts Maa on syntinen laulu. Balladi (1964), Tabu (1965), Täältä jostakin. Romaani (1965), Laulu Sipirjan lapsista. Romaani (1966), Ja kesän heinä kuolee. Kertomus sairaudesta (1968) ja Kyyhky ja unikko (1970) and the short story collections Koiran kuolema (1967) ja Lumen pelko (1970), and with Tabu published short story Sankarihymni , the short story Katkelma laajemmasta laulelmasta from the collection Rakastaa: Kaksitoista novellia rakkaudesta (1965) and also the short stories which were published in various Finnish journals: Yöt (1965), Liisa (1967), Tyttö (1967) ja Näin hetki sitten ketun (1970). I pay particular attention to the novel Maa on syntinen laulu, because it expresses the generic change characteristic of Mukka s world view in a specifically clear and lively way. The dissertation is in Finnish. Key words: Timo K. Mukka, world view, genre change, ballad, naturalism, grotesque realism, Mikhail Bakhtin, dialogism, polyphony, chronotope, sublime, grotesque, ressentiment, Sigmund Freud, melancholy, taboo, abject, sadism, reduced laughter, modern parody.

Two stage Gifford-McMahon cycle cryorefrigerator operating at 20 K

A two stage Gifford-McMahon cycle cryorefrigerator operating at 20 K is described. This refrigerator uses a very simple ‘spool valve’ and a modified indigenous compressor to compress helium gas. This cryorefrigerator reaches a lowest temperature of 15.5 K; it takes ≈ 50 min to reach 20 K and the cooling capacity is ≈ 2.5 W at 25 K. The cool-down characteristics and load characteristics are presented in graphical form. The effect of changing the operating pressure ratio and the second stage regenerator matrix size are also reported. Pressure-volume (P-V) diagrams obtained at various temperatures indicate that P-V losses form the major fraction of the total losses and this becomes more pronounced as the temperature is decreased. A heat balance analysis shows the relative magnitudes of various losses.

Chemical synthesis and structure elucidation of bovine K-casein (1-44)

The caseins (αs1, αs2, β, and κ) are phosphoproteins present in bovine milk that have been studied for over a century and whose structures remain obscure. Here we describe the chemical synthesis and structure elucidation of the N-terminal segment (1–44) of bovine κ-casein, the protein which maintains the micellar structure of the caseins. κ-Casein (1–44) was synthesised by highly optimised Boc solid-phase peptide chemistry and characterised by mass spectrometry. Structure elucidation was carried out by circular dichroism and nuclear magnetic resonance spectroscopy. CD analysis demonstrated that the segment was ill defined in aqueous medium but in 30% trifluoroethanol it exhibited considerable helical structure. Further, NMR analysis showed the presence of a helical segment containing 26 residues which extends from Pro8 to Arg34. This is the first report which demonstrates extensive secondary structure within the casein class of proteins.

Determination of the thermodynamic properties of xMgO + (1 x)MnO (s, sln) from a solid-electrolyte galvanic cell in the temperature range 1163 to 1318 K

The thermodynamic activities of MgO in the NaCl-type solid solutions which can exist in xMgO + (1 x)MnO have been determined in the temperature range 1163 to 1318 K from a solid-state galvanic cell incorporating MgF2 as the solid electrolyte. The activities of MnO have been calculated by a graphical Gibbs-Duhem integration method. The activities of both the components exhibit positive deviations from ideality over the entire composition range. The excess molar enthalpies are found to be positive. Further, xMgO + (1 - x)MnO does not conform to regular-solution behaviour. The origin of the excess thermodynamic properties is discussed in relation to the cationic size disparity and the crystal-field effects.