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PMID:697776

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AbstractThree new species of parasitic mites of the genus Neharpyrhynchus Fain (Acariformes,...Full Text Available

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The tegument of tapeworms is known to be composed of an outer syncytial cytoplasm layer which includes microtriches and cytoplasmic organelles (= syncytial layer), and a parenchymatous cytoplasm layer...Full Text Available

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The tapeworm Spirometra mansonoides infects man worldwide, particularly in Asian countries. Rarely, the central nervous system is involved; such a case is presented here. In the total of 12 reported cases, including the case described, the worm presented clinically as a mass suspicious for neoplasm or chronic abscess cavity. Surgical removal was invariably curative in each case. Although infrequent, the possibility of tapeworm infection should be entertained in the evaluation of intracranial masses in patients who have visited exotic locales. PMID:2191089

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Organisms in the genus Mycobacterium cause a variety of human diseases. One member of the genus, M. ulcerans, causes a necrotizing skin disease called Buruli ulcer....Full Text Available

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... eremicus (Baker, 1904). The second species, Malaraeus telchinus (Rothschild, 1905), is the commonest member of the genus. ... described by Baker (1904), Jordan (1929), Kolenati (1857), Rothschild (1922), ...

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Picocyanobacteria of the genus Synechococcus are important contributors to marine primary production and are ubiquitous in the world's oceans. This genus is genetically diverse, and...Full Text Available

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... The genus Ipomea contains a species, Ipomea , which contains a purgative (Jl). Ipomea batatus is not known to contain this substance. ...

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We propose a generalization of the character formulas of the SU(2) Kac-Moody algebra to higher genus Riemann surfaces. With this construction, we show that the modular invariant partition funciton of the SO(4) k = 1 Wess-Zumino model is equivalent, in arbitrary genus Riemann surfaces, to that of free fermion theory.

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Topologically non trivial effects appearing in the discussion of duality transformations in higher genus manifold are discussed in a simple example, and their relation with the properties of Topological Field Theories is established. (author). 16 refs.

International Nuclear Information System (INIS)

We show how the formulation of the matrix models as conformal field theories on a Riemann surfaces can be used to compute the genus expansion of the observables. Here we consider the simplest example of the Hermitian matrix model, where the classical solution is described by a hyperelliptic Riemann surface. To each branch point of the Riemann surface we associate an operator which represents a twist field dressed by the modes of the twisted boson. The partition function of the matrix model is computed as a correlation function of such dressed twist fields. The perturbative construction of the dressing operators yields a set of Feynman rules for the genus expansion, which involve vertices, propagators and tadpoles. The vertices are universal, the propagators and the tadpoles depend on the Riemann surface. As a demonstration we evaluate the genus-two free energy using the Feynman rules.

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The evolutionary history of the reef fish genus Naso (F. Acanthuridae) was examined using a complete species-level molecular phylogeny of all recognized (19) species based on three loci (one nuclear ETS2 and two mitochondrial 16S, cyt b). This study demonstrates that distinct foraging modes and specialized body shapes arose independently at different times in the evolutionary history of the genus. Members of the subgenus Axinurus, characterized by a scombriform morphology, caudal fin structure and pelagic foraging mode, were consistently placed basal to the remaining Naso species, suggesting that pelagic foraging is plesiomorphic and benthic foraging derived in this genus. We used a genus-level phylogeny (nuclear marker, ETS2), which included several taxa from all other acanthurid genera, to obtain a range of age estimates for the most recent common ancestor of the genus Naso. These ...

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Abstract Mitochondrial ribosomal gene sequences were used to investigate the status of several populations of hydromedusae belonging to the genus Turritopsis (family Oceaniidae). Several nominal species have been described for this genus, but most of them had been synonymized and attributed to one cosmopolitan species, Turritopsis nutricula. A recent revision based on morphological and reproductive characters, however, has shown that many different populations can be distinguished and that several of the nominal Turritopsis species are likely valid biological species. Our investigation using molecular sequence data of 16S mitochondrial gene confirms these results. The Mediterranean Turritopsis must be attributed to Turritopsis dohrnii and the Turritopsis of New Zealand must be referred to ...

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We describe in detail the space of the two Kaehler parameters of the Calabi-Yau manifold P_4"("1","1","1","6","9")[D. R. Morrison, 1993] by exploiting mirror symmetry. The large complex structure limit of the mirror, which corresponds to the classical large radius limit, is found by studying the monodromy of the periods about the discriminant locus, the boundary of the moduli space corresponding to singular Calabi-Yau manifolds. A symplectic basis of periods is found and the action of the Sp(6, Z) generators of the modular group is determined. From the mirror map we compute the instanton expansion of the Yukawa couplings and the generalized N=2 index, arriving at the numbers of instantons of genus zero and genus one of each bidegree. We find that these numbers can be negative, even in genus zero. We also investigate an SL(2, Z) symmetry that acts on a boundary of the moduli space. ((orig.)).

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Algal allelopathy is an ecological/physiological phenomenon that has focused attention on the interactions among algae and the production of algal toxins. We investigated the allelopathic interactions between the dinoflagellate genus Prorocentrum micans and diatom genus Skeletonema costatum and between P. micans and dinoflagellate genus Karenia mikimotoi using bi-algal cultures. Because the effects were species-specific and size-dependent, we evaluated the effect of different initial densities. At low densities of P. micans and high densities of S. costatum inoculated into the same medium, the growth of P. micans was weakly restrained, whereas the growth of S. costatum was significantly suppressed. S. costatum and K. mikimotoi were strongly inhibited by P. micans, in both the bi-algal cult...

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Mycobacterium tuberculosis is one of the strongest reducers of nitrate in the genus Mycobacterium. Under microaerobic conditions, whole cells exhibit upregulation of...Full Text Available

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Plastid genome content and arrangement are highly conserved across most land plants and their closest relatives, streptophyte algae, with nearly all plastid introns having invaded the genome in their...Full Text Available

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... Wrenn. References CitedBanerjee, S., and Nandi, B. 1992 Fossil fungi from Miocene sediments of Mizoram and their environmental ... ...

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Hydrothermal vent mussels belonging to the genus Bathymodiolus are distributed worldwide and dominate communities at shallow Atlantic hydrothermal sites. While organisms inhabiting...Full Text Available

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BackgroundCichlid fishes in Lake Tanganyika exhibit remarkable diversity in their feeding habits. Among them, seven species in the genus Perissodus are known for...Full Text Available

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Organisms belonging to the genus Streptomyces produce numerous important secondary metabolites and undergo a sophisticated morphological differentiation program. In many instances these...Full Text Available

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Somatogenic hormones play an important role in regulation of receptors for prolactin (PRL) and estrogen. Plerocercoids of the tapeworm, S. mansonoides produce a factor which mimics some, but not all of the actions reported for GH. Intact female rats were subjected to a constant infusion of plerocercoid growth factor (PGF) via a subcutaneous infection for two weeks to determine if PGF influences receptors for PRL, GH or estradiol. The rate of weight gain in the PGF-treated rats was accelerated in spite of a marked reduction in serum GH. Partially-purified PGF specifically displaced [125I]hGH from rat liver receptors but microsomes prepared from rats treated with PGF specifically bound significantly less [125I]hGH than microsomes from control rats. The reduction in [125I]hGH binding was not due to occupancy or to a change in affinity but to a suppression in receptor concentration. Scatchard analysis of [3H]estradiol binding in rat liver cytosols shows a 50% reduction ...

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Toadlets of the genus Brachycephalus are endemic to the Atlantic rainforests of southeastern and southern Brazil. The 14 species currently described have snout-vent lengths less than 18mm and are thought to have evolved through miniaturization: an evolutionary process leading to an extremely small adult body size. Here, we present the first comprehensive phylogenetic analysis for Brachycephalus, using a multilocus approach based on two nuclear (Rag-1 and Tyr) and three mitochondrial (Cyt b, 12S, and 16S rRNA) gene regions. Phylogenetic relationships were inferred using a partitioned Bayesian analysis of concatenated sequences and the hierarchical Bayesian method (BEST) that estimates species trees based on the multispecies coalescent model. Individual gene trees showed conflict and also va...

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Various control procedures have been suggested for reducing foodborne infectious diseases. Receiving considerable attention is irradiation. This report estimates the medical and wage (or productivity) benefits associated with prevention of five human diseases transmitted by beef, pork, and chicken. (These diseases can also be transmitted by other vectors, such as eggs, milk, and pets. But these sources are not included in the analysis.) All of these foodborne infectious diseases - salmonellosis, campylobacteriosis, trichinosis, tapeworm, and toxoplasmosis - could be significantly reduced by irradiating meat and poultry. The Food and Drug Administration (FDA) has just approved irradiation of pork to prevent trichinosis (50FR 29658-59) and is considering approval of irradiation of chicken to kill Salmonella. 22 references.

International Nuclear Information System (INIS)

It was shown by Gibbons and Tsarev (1996 Phys. Lett. A 211 19, 1999 Phys. Lett. A 258 263) that N-parameter reductions of the Benney equations correspond to particular N-parameter families of conformal maps. In recent papers (Baldwin and Gibbons 2003 J. Phys. A: Math. Gen. 36 8393-417, Baldwin and Gibbons 2004 J. Phys. A: Math. Gen. 37 5341-54), the present authors have constructed examples of such reductions where the mappings take the upper half p-plane to a polygonal slit domain in the #lambda#-plane. In those cases, the mapping function was expressed in terms of the derivatives of Kleinian #sigma# functions of hyperelliptic curves, restricted to the one-dimensional stratum #THETA#_1 of the #THETA#-divisor. This was done using an extension of the method given in Enolskii et al (2003 J. Nonlinear Sci. 13 157) extended to a genus 3 curve (Enolski V Z and Gibbons J Addition theorems on the strata of the theta divisor of genus three ...

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A factor produced by plerocercoids of the tapeworm Spirometra mansonoides is similar to human growth hormone (hGH) in that it stimulates body growth, binds to hGH receptors, cross-reacts with anti-hGH antibodies, and has lactogenic and insulin-like activities. The purpose of this study was to determine whether plerocercoid growth factor (PGF) is similar to hGH in expressing diabetogenic activity in the genetically obese (ob/ob) mouse. To determine an effective dose for use in the obese mice, the ability of daily injections of PGF to stimulate growth of phenotypically normal mice of the same strain was assessed in a 10-day weight gain assay. Injections of PGF stimulated a dose-dependent weight gain (r = 0.83) and 25 ng eq/day of PGF stimulated a response not significantly different from that produced by 100 micrograms of bovine growth hormone/day. Diabetogenicity was assessed using fasting blood glucose and glucose tolerance tests in obese mice that had been ...

CERN Document Server

Let $C$ be a curve of genus two. We denote by $SU_C(3)$ the moduli space of semi-stable vector bundles of rank 3 and trivial determinant over $C$, and by $J^d$ the variety of line bundles of degree $d$ on $C$. In particular, $J^1$ has a canonical theta divisor $\\Theta$. The space $SU_C(3)$ is a double cover of $P^8=|3\\Theta|$ branched along a sextic hypersurface, the Coble sextic. In the dual $\\check{P}^8=|3\\Theta|^*$, where $J^1$ is embedded, there is a unique cubic hypersurface singular along $J^1$, the Coble cubic. We prove that these two hypersurfaces are dual, inducing a non-abelian Torelli result. Moreover, by looking at some special linear sections of these hypersurfaces, we can observe and reinterpret some classical results of algebraic geometry in a context of vector bundles: the duality of the Segre-Igusa quartic with the Segre cubic, the symmetric configuration of 15 lines and 15 points, the Weddle quartic surface and the Kummer surface.

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The symbiotic polychaetes of the genus Osedax living on the bones of whale carcasses have become known as bone-eating worms. It is believed that whale bones are the source of nutrition for those gutless worms and that fatty acids are produced by their symbionts and transferred to the host. However, the symbionts are of the heterotrophic group Oceanospirillales and as such are not able to synthesize organic carbon de novo. Also, they are not housed in close contact to the bone material. We studied the ultrastructure of the integument overlying the symbiont housing trophosome in the ovisac region and the roots region and of the symbiont-free trunk region of Osedax to investigate the hosts possible contribution in feeding for the whole symbiosis. The epidermis differs conspicuously between th...

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Marburg virus belongs to the genus Marburgvirus in the family Filoviridae and causes a severe hemorrhagic fever, known as Marburg hemorrhagic fever (MHF), in both humans and nonhuman primates. Similar to the more widely known Ebola hemorrhagic fever, MHF is characterized by systemic viral replication, immunosuppression and abnormal inflammatory responses. These pathological features of the disease contribute to a number of systemic dysfunctions including hemorrhages, edema, coagulation abnormalities and, ultimately, multiorgan failure and shock, often resulting in death. A detailed understanding of the pathological processes that lead to this devastating disease remains elusive, a fact that contributes to the lack of licensed vaccines or effective therapeutics. This article will review the...

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Plerocercoids of the tapeworm Spirometra mansonoides produce a substance that stimulates growth of experimental hosts. We report purification of plerocercoid growth factor (PGF) to homogeneity by a process involving isolation and solubilization of plerocercoid membranes, isoelectric point selection by chromatofocusing chromatography or preparative isoelectric focusing, and anion-exchange chromatography. A radioreceptor assay (RRA) for human growth hormone (hGH) was used to detect PGF and purity of the 27.5-kDa protein was judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Proteolytic activity was detected in the 27.5-kDa protein by gelatin substrate PAGE. Characterization of PGF as a neutral cysteine proteinase was based on substrate and inhibitor specificities and dependence on pH and thiol-containing reagents. The association of hGH agonist and proteinase activities was shown by comparing RRA and hydrolytic activities in the presence ...

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Postresection villus hyperplasia is a major compensatory mechanism in the short-bowel patient. Substances capable of augmenting postresection mucosal hyperplasia could have therapeutic implications. Human growth hormone (hGH) and human growth hormone releasing factor (hGHRF) stimulate growth of the gastrointestinal tract; however, the diabetogenic actions of growth hormone limit its usefulness in clinical practice. Plerocercoid larvae of the tapeworm Spirometra mansonoides produce an analog of hGH void of diabetogenic side effects. We assessed effects of plerocercoid growth factor (PGF) on mucosal adaptation following 70% proximal jejunoileal resection in young rats. Mucosal weight, DNA, protein, and total sucrase activity per centimeter of bowel were increased in resected PGF-treated animals compared to resected controls. We conclude PGF augments intrinsic postresection mucosal hyperplasia following extensive intestinal resection. PMID:3665682

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Iguanian lizards form a diverse clade whose members have been the focus of many comparative studies of ecology, behavior, and evolution. Despite the importance of phylogeny to such studies, interrelationships among many iguanian clades remain uncertain. Within the Old World clade Acrodonta, Agamidae is sometimes found to be paraphyletic with respect to Chamaeleonidae, and recent molecular studies have produced conflicting results for many major clades. Within the largely New World clade Pleurodonta, relationships among the 12 currently recognized major subclades (mostly ranked as families) have been largely unresolved or poorly supported in previous studies. To clarify iguanian evolutionary history, we first infer phylogenies using concatenated maximum-likelihood (ML) and Bayesian analyses of DNA sequence data from 29 nuclear protein-coding genes for 47 iguanian and 29 outgroup taxa. We then estimate a relaxed-clock Bayesian chronogram for iguanians using BEAST. All three methods ...

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Humic acids are considered problematically in drinking water because it can react readily with chlorine to form carcinogen compounds and its biological removal is much recommended. The scanning electron microscopy morphologies and optical parameters observed for natural humic acids (NHAs) extracted from different soils at Mitidja plain (Algeria) made them different from the commercial ones. Three of the most active strains of 19 actinomycetes were isolated and selected from surface soils at this plain. These strains were identified based on cultural characteristics and chemotaxonomic analysis and classified in the genus Streptomyces. Growth of these strains was assured on a poor liquid medium containing NHAs as carbon and nitrogen sources and degradation occur only in the presence of gluco...

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Mimivirus is the prototype of a new family (the Mimiviridae) of nucleocytoplasmic large DNA viruses (NCLDVs), which already include the Poxviridae, Iridoviridae, Phycodnaviridae and Asfarviridae. Mimivirus specifically replicates in cells from the genus Acanthamoeba. Proteomic analysis of purified mimivirus particles revealed the presence of many subunits of the DNA-directed RNA polymerase II complex. A fully functional pre-transcriptional complex appears to be loaded in the virions, allowing mimivirus to initiate transcription within the host cytoplasm immediately upon infection independently of the host nuclear apparatus. To fully understand this process, a systematic study of mimivirus proteins that are predicted (by bioinformatics) or suspected (by proteomic analysis) to be involved in...

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Abstract Estimating paternity patterns provides insights into the importance of competing evolutionary forces on mating systems. The number of sires contributing to a female's offspring is mostly influenced by her relative promiscuity. However, in a postcopulatory context, it will also be affected by sperm competition and cryptic female choice. Here, we describe the paternity patterns of two species of praying mantis from the genus Ciulfina, the agile praying mantid. This study is the first to describe patterns of paternity in the Mantodea. We found a variation in paternity in these two closely related species. Ciulfina rentzi exhibited single paternity, with a single male siring all offspring within a clutch. By contrast, Ciulfina klassi displayed multiple paternity, with the minimum numb...

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Studies were carried out on the decolorization of textile azo dyes by newly isolated halophilic and halotolerant bacteria. Among the 27 strains of halophilic and halotolerant bacteria isolated from effluents of textile industries, three showed remarkable ability in decolorizing the widely utilized azo dyes. Phenotypic characterization and phylogenetic analysis based on 16S rDNA sequence comparisons indicate that these strains belonged to the genus Halomonas. The three strains were able to decolorize azo dyes in a wide range of NaCl concentration (up to 20%w/v), temperature (25-40degreeC), and pH (5-11) after 4 days of incubation in static culture. They could decolorize the mixture of dyes as well as pure dyes. These strains also readily grew in and decolorized the high concentrations of dy...

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Thirty bacterial isolates were obtained from different sources and sites at Jeddah, Saudi Arabia, on chitin agar medium; 9 of the 30 isolates were cultured in liquid medium containing chitin as sole carbon and nitrogen sources. Isolate SM21, which was isolated from shrimp shells, showed the best growth and chitinase production in liquid medium. According to its morphological, physiological and biochemical characteristics, SM21 belongs to the genus Streptomyces and was identified as Streptomyces anulatus SM21. Identification was confirmed using 16S rDNA analysis. The chitinase enzyme was precipitated with 80% NH4SO4 and purified using DEAE-cellulose ion exchange chromatography followed by Sephadex G-100 gel filtration. The molecular weight determined using sodium dodecyl sulfate polyacrylam...

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Banana bunchy top virus (BBTV), family Nanaviridae, genus Babuvirus, is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants. It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region. In this study we isolated, cloned and sequenced a BBTV sample from Hainan Island, China. The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs. We also predicted the physical and chemical properties, structure, signal peptide, phosphorylation, secondary structure, tertiary structure and functional domains of its encoding protein, and compare them with the corresponding quantities in the replication initiatio...

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Eremostachys laciniata (L) Bunge (family: Lamiaceae alt. Labiatae; subfamily: Lamioideae) is one of the 15 endemic Iranian herbs of the genus Eremostachys. A decoction of the roots and flowers of E. laciniata has traditionally been taken orally for the treatment of allergies, headache and liver diseases. Three antibacterial iridoid glucosides, phloyoside I (1), phlomiol (2) and pulchelloside I (3) have been isolated from the rhizomes of this plant. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. The antibacterial activity and brine shrimp toxicity of these compounds were assessed using the resazurin microtitre assay and the brine shrimp lethality assay, respectively. All three iridoid glycosides 1-3 exhibited from low to moderate level...

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The ecological success of shallow-water reef-building corals (Hexacorallia: Scleractinia) is framed by their intimate endosymbiosis with photosynthetic dinoflagellates in the genus Symbiodinium (zooxanthellae). In contrast, the closely related black corals (Hexacorallia: Anthipatharia) are described as azooxanthellate (lacking Symbiodinium), a trait thought to reflect their preference for low-light environments that do not support photosynthesis. We examined 14 antipatharian species collected between 10 and 396 m from Hawai'i and Johnston Atoll for the presence of Symbiodinium using molecular typing and histology. Symbiodinium internal transcribed spacer-2 (ITS-2) region sequences were retrieved from 43 per cent of the antipatharian samples and 71 per cent of the examined species, and across the entire depth range. The ITS-2 sequences were identical or very similar to those commonly found in shallow-water scleractinian corals throughout the Pacific. Histological ...

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The metabolic actions of GH can be divided into acute (insulin-like) and chronic (lipolytic/anti-insulin). The insulin-like actions of GH are most readily elicited in GH-deficient animals as GH induces resistance to its own insulin-like action. Like GH, PGF stimulates growth and cross-reacts with anti-hGH antibodies. Independent experiments were conducted comparing the direct actions of PGF to insulin or hGH in vitro. Insulin-like effects were determined by the ability of PGF, insulin or hGH to stimulate [U-"1"4C]glucose metabolism in epidydimal fat pads from normal rats and by inhibition of epinephrine-stimulated lipolysis. Direct stimulation of lipolysis was used as anti-insulin activity. To determine if PGF competes for insulin or GH receptors, adipocytes (3 x 10"5 cells/ml) were incubated with either ["1"2"5I]insulin or ["1"2"5I]hGH +/- PGF, +/- insulin or +/- hGH. PGF stimulated glucose oxidation and "1"4C-incorporation into lipids. Insulin, hGH and PGF inhibited lipolysis (33%, ...

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A factor produced by the plerocercoid stage of S. mansonoides mimics some, but not all, of the actions reported for hGH. The biological actions of plerocercoid growth factor (PGF) suggest structural similarity to human GH (hGH). Plerocercoid membranes were solubilized, and PGF was purified more than 1000-fold by hGH receptor affinity chromatography. The ability of purified PGF to displace [125I]hGH from monoclonal antibodies specific for four distinct nonoverlapping antigenic determinants of hGH and from an anti-hGH polyclonal antibody was tested in liquid phase RIA. All of the hGH antibodies cross-reacted with PGF, with potencies ranging from more than 60% to less than 1% that of the hGH standard. Of the four major epitopes of hGH defined by the monoclonal antibodies used in this study, only one is not represented to a significant extent in PGF. The epitope of hGH that is only marginally present in PGF is highly conformationally dependent, and a minor difference in the structure of ...

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We argue that closed string tachyons drive two spacetime topology changing transitions--loss of genus in a Riemann surface and separation of a Riemann surface into two components. The tachyons of interest are localized versions of Scherk-Schwarz winding string tachyons arising on Riemann surfaces in regions of moduli space where string-scale tubes develop. Spacetime and world-sheet renormalization group analyses provide strong evidence that the decay of these tachyons removes a portion of the spacetime, splitting the tube into two pieces. We address the fate of the gauge fields and charges lost in the process, generalize it to situations with weak flux backgrounds, and use this process to study the type 0 tachyon, providing further evidence that its decay drives the theory sub-critical. Finally, we discuss the time-dependent dynamics of this topology-changing transition and find that it can occur more efficiently than analogous transitions on extended ...

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During last decade, considerable interest has been focused to assess the influence of human activities on ecosystems. The increasing trend in the atmospheric concentration of CO{sub 2} has been predicted to continue till the next century and the amount of nitrogen deposition in the northern hemisphere has increased markedly. Substantial interest has been focused on predicting how these changes will affect on plants. Most boreal mire ecosystems are dominated by mosses of the genus Sphagnum, the litter of which constitutes the main component in the peat deposits and is an important CO{sub 2} sink via peat formation. Since virtually nothing was known about the growth response of peat mosses to elevated concentrations of CO{sub 2} and alerting changes in species composition were detected in the sensitive ombrotrophic mire vegetation under increased N deposition in central Europe, this study was established. Laboratory experiments focused on measurements of the patterns ...

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Chinese herbs have been and still are widely used as important remedies in Oriental medicine. Over the recent years, a variety of biologically active constituents have been isolated from these sources and confirmed to have multifunctional activity in experimental studies. Honokiol is a small-molecule polyphenol isolated from the genus Magnolia. It is accompanied by other related polyphenols, including magnolol, with which it shares certain biological properties. Recently, honokiol and magnolol have been found to have anti-oxidative, anti-inflammatory, anti-tumor, and anti-microbial properties in preclinical models, without appreciable toxicity. These findings have increased interest in bringing honokiol and magnolol to the clinic as novel therapeutic agents in dermatology. In this review, the findings concerning the major mechanisms of action of honokiol and magnolol are described. Knowledge of the multiple activities of honokiol and magnolol can assist with the ...

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Four materials, carbon felt cube (CFC), granular graphite (GG), granular activated carbon (GAC) and granular semicoke (GS) were tested as packed anodic materials to seek a potentially practical material for microbial fuel cells (MFCs). The microbial community and its correlation with the electricity generation performance of MFCs were explored. The maximum power density was found in GAC, followed by CFC, GG and GS. In GAC and CFC packed MFCs, Geobacter was the dominating genus, while Azospira was the most populous group in GG. Results further indicated that GAC was the most favorable for Geobacter adherence and growth, and the maximum power densities had positive correlation with the total biomass and the relative abundance of Geobacter, but without apparent correlation with the microbial diversity. Due to the low content of Geobacter in GS, power generated in this system may be attributed to other microorganisms such as Synergistes, Bacteroidetes and ...

CERN Document Server

The centre of the symmetric group algebra $\\mathbb{C}[\\mathfrak{S}_n]$ has been used successfully for studying important problems in enumerative combinatorics. These include maps in orientable surfaces and ramified covers of the sphere by curves of genus $g$, for example. However, the combinatorics of some equally important $\\mathfrak{S}_n$-factorization problems forces $k$ elements in $\\{1,...,n\\}$ to be distinguished. Examples of such problems include the star factorization problem, for which $k=1,$ and the enumeration of 2-cell embeddings of dipoles with two distinguished edges \\cite{VisentinWieler:2007} associated with Berenstein-Maldacena-Nastase operators in Yang-Mills theory \\cite{ConstableFreedmanHeadrick:2002}, for which $k=2.$ Although distinguishing these elements obstructs the use of central methods, these problems may be encoded algebraically in the centralizer of $\\mathbb{C}[\\mathfrak{S}_n]$ with respect to the subgroup $\\mathfrak{S}_{n-k}.$ ...

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The occurrence of hybrid incompatibilities forms an important stage during the evolution of reproductive isolation. In early stages of speciation, males and females often respond differently to hybridization. Haldane's rule states that the heterogametic sex suffers more from hybridization than the homogametic sex. Although haplodiploid reproduction (haploid males, diploid females) does not involve sex chromosomes, sex-specific incompatibilities are predicted to be prevalent in haplodiploid species. Here, we evaluate the effect of sex/ploidy level on hybrid incompatibilities and locate genomic regions that cause increased mortality rates in hybrid males of the haplodiploid wasps Nasonia vitripennis and Nasonia longicornis. Our data show that diploid F(1) hybrid females suffer less from hybridization than haploid F(2) hybrid males. The latter not only suffer from an increased mortality rate, but also from behavioural and spermatogenic sterility. Genetic mapping in recombinant F(2) male ...

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The biodegradation of one of the most commonly used commercially available dispersants in the treatment of hydrocarbon out-flow was studied. The culture mediums employed were sea water, sterile sea water, and medium M19 (Merck). The latter two were inoculated with two kinds of microorganisms of the Pseudomona genus isolated from sludge from a waste treatment plant. The dispersants used is a commercial product made of anionic sulphated dispersants (1.710% by weight); anionic sulphonated dispersants (0.144%) and non-ionic dispersants (8.146%), both accompained by hidrocarbonated solvent (90%). The degradation processes occurred at differents temperatures (20, 30 and 37). The greatest degradation was obtained at 30 degree centigree. The degradation percentages obtained with the miscroorganisms were 40% of the anionic total and 70% of the non-ionic total after 56 hours for the 5:2 strain and 40% of the anionic total and 9.3% of the non-ionic total after 186 hours for ...