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Efeitos do polietilenoglicol 3350 e de soluções acidificantes e alcalinizantes sobre o perfil bioquímico de éguas hígidas

Gomes,C.L.N.; Ribeiro Filho,J.D.; Guimarães,J.D.; Meneses,R.M.
Fonte: Universidade Federal de Minas Gerais, Escola de Veterinária Publicador: Universidade Federal de Minas Gerais, Escola de Veterinária
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 PT
Relevância na Pesquisa
26.2%
Avaliou-se o perfil bioquímico de cinco éguas hígidas tratadas com polietilenoglicol 3350 (PEG); ou com polietilenoglicol 3350+Ringer lactato (PEG+RL); ou com solução isotônica poliônica enteral (SIPE); ou com solução isotônica poliônica enteral associada ao Ringer lactato intravenoso (SIPE+RL); ou com solução de cloreto de sódio a 0,9% (NaCl 0,9%). Os parâmetros avaliados foram: sódio, cloreto, potássio, cálcio ionizado, fósforo, magnésio total, proteínas totais, albumina, creatinina, ureia e osmolaridade calculada no soro de sangue venoso. O tratamento PEG não alterou os parâmetros bioquímicos. O PEG+RL diminuiu o fósforo. O SIPE diminuiu o fósforo e aumentou o cloreto. O SIPE+RL aumentou o sódio, e o NaCl 0,9% ocasionou o aumento do cloreto e a redução da osmolaridade sérica. Concluiu-se que o tratamento PEG associado ao Ringer lactato pode provocar o aparecimento de hipofosfatemia, o SIPE ocasiona hipercloremia, o NaCl 0,9% diminui a osmolaridade sérica e o SIPE+RL provoca hipernatremia.

Effects of elevated atmospheric CO2 concentration on leaf dark respiration of Xanthium strumarium in light and in darkness

Wang, Xianzhong; Lewis, James D.; Tissue, David T.; Seemann, Jeffrey R.; Griffin, Kevin L.
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: Artigo de Revista Científica
Publicado em 27/02/2001 EN
Relevância na Pesquisa
26.33%
Leaf dark respiration (R) is an important component of plant carbon balance, but the effects of rising atmospheric CO2 on leaf R during illumination are largely unknown. We studied the effects of elevated CO2 on leaf R in light (RL) and in darkness (RD) in Xanthium strumarium at different developmental stages. Leaf RL was estimated by using the Kok method, whereas leaf RD was measured as the rate of CO2 efflux at zero light. Leaf RL and RD were significantly higher at elevated than at ambient CO2 throughout the growing period. Elevated CO2 increased the ratio of leaf RL to net photosynthesis at saturated light (Amax) when plants were young and also after flowering, but the ratio of leaf RD to Amax was unaffected by CO2 levels. Leaf RN was significantly higher at the beginning but significantly lower at the end of the growing period in elevated CO2-grown plants. The ratio of leaf RL to RD was used to estimate the effect of light on leaf R during the day. We found that light inhibited leaf R at both CO2 concentrations but to a lesser degree for elevated (17–24%) than for ambient (29–35%) CO2-grown plants, presumably because elevated CO2-grown plants had a higher demand for energy and carbon skeletons than ambient CO2-grown plants in light. Our results suggest that using the CO2 efflux rate...

Preservation of hemostatic and structural properties of rehydrated lyophilized platelets: potential for long-term storage of dried platelets for transfusion.

Read, M S; Reddick, R L; Bode, A P; Bellinger, D A; Nichols, T C; Taylor, K; Smith, S V; McMahon, D K; Griggs, T R; Brinkhous, K M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 17/01/1995 EN
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26.25%
Currently, therapeutic platelet concentrates can be stored for only 5 days. We have developed a procedure that permits long-term storage of fixed and lyophilized platelets that retain hemostatic properties after rehydration. These rehydrated lyophilized platelets (RL platelets) restore hemostasis in thrombocytopenic rats and become incorporated in the hemostatic plug of bleeding time wounds of normal dogs as well as von Willebrand disease dogs with partially replenished plasma von Willebrand factor. Ultrastructurally, these platelets are well preserved and are comparable to control normal washed platelets. Flow cytometry analysis shows that RL platelets react with antibodies to the major surface receptors, glycoprotein (GP)Ib and GPIIb/IIIa. These receptors are involved in platelet agglutination, aggregation, and adhesion. In vitro functional tests document the ability of RL platelets to adhere to denuded subendothelium and to spread on a foreign surface. Circulating RL platelets participated in carotid arterial thrombus formation induced in normal canine subjects. The participation of RL platelets in these vital hemostatic properties suggests that with further development they could become a stable platelet product for transfusion.

Retention of Photoinduction of Cytosolic Enzymes in aurea Mutant of Tomato (Lycopersicon esculentum).

Goud, K. V.; Sharma, R.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1994 EN
Relevância na Pesquisa
26.26%
The tomato (Lycopersicon esculentum Mill.) aurea (au) mutant has been characterized as a phytochrome-deficient mutant lacking spectrally detectable phytochrome A in etiolated seedlings. Seedlings of au grown under red light (RL) lack phytochrome regulation of nuclear genes encoding plastidic proteins, possess ill-developed chloroplasts, and are slow to de-etiolate. In the present study, the effect of phytochrome deficiency on photoinduction of enzymes in etiolated au seedlings was investigated. The photoinduction of the cytosolic enzymes amylase and nitrate reductase (NR) and of the plastidic enzyme nitrite reductase (NiR) in au was compared with that in the isogenic wild-type (WT) tomato and the high-pigment (hp) mutant with exaggerated phytochrome response. In WT and hp, both brief RL pulses and continuous RL induced amylase, NR, and NiR activities, whereas in au no photoinduction of enzymes was observed with brief RL pulses, and continuous RL induced only amylase and NR activities. The time courses of photoinduction of NR and amylase in au under continuous RL followed patterns qualitatively similar to hp and WT. A blue-light pretreatment prior to continuous RL exposure was ineffective in inducing NiR activity in au. Only continuous white light could elicit a photoinduction of NiR in au seedlings. The norflurazon-triggered loss of photoinduction of NiR in WT and hp indicated that NiR photoinduction depended on chloroplast biogenesis. The results indicate that observed photoinduction of NR and amylase in au may be mediated by a residual phytochrome pool.

Development of a 16S rRNA-based oligomer probe specific for Listeria monocytogenes.

Wang, R F; Cao, W W; Johnson, M G
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1991 EN
Relevância na Pesquisa
26.3%
Crude rRNA was isolated from Listeria monocytogenes, L. innocua, and L. ivanovii and sequenced by a reverse transcriptase method. Only two sequence regions were found to differ for L. monocytogenes versus L. innocua or L. ivanovii. Two oligonucleotide probes (RL-1 and RL-2) complementary to these two regions of rRNA of L. monocytogenes were synthesized. The RL-1 probe had one base while the RL-2 probe had two bases which differed for L. monocytogenes versus L. innocua and L. ivanovii. Use of a dried gel hybridization in place of Northern (RNA) hybridization or dot blot hybridization indicated that the RL-2 probe hybridized with all 36 strains of L. monocytogenes tested but not with 6 other Listeria species and 11 other bacteria tested. The RL-2 probe is specific for L. monocytogenes, while the RL-1 probe showed some cross-reactions with other Listeria species. An alkaline phosphatase-labeled RL-2 probe could be used in a dot blot hybridization test and gave good results, but a 32P-labeled RL-2 probe was more sensitive than the nonradioactive probe and the 32P-labeled probe was useable for up to 2 months, even though the 32P was highly degenerated.

Rapid induction in regenerating liver of RL/IF-1 (an I kappa B that inhibits NF-kappa B, RelB-p50, and c-Rel-p50) and PHF, a novel kappa B site-binding complex.

Tewari, M; Dobrzanski, P; Mohn, K L; Cressman, D E; Hsu, J C; Bravo, R; Taub, R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1992 EN
Relevância na Pesquisa
36.29%
The liver is one of the few adult tissues that has the capacity to regenerate following hepatectomy or toxic damage. In examining the early growth response during hepatic regeneration, we found that a highly induced immediate-early gene in regenerating liver encodes RL/IF-1 (regenerating liver inhibitory factor) and is the rat homolog of human MAD-3 and probably of chicken pp40. RL/IF-1 has I kappa B activity of broad specificity in that it inhibits the binding of p50-p65 NF-kappa B, c-Rel-p50, and RelB-p50, but not p50 homodimeric NF-kappa B, to kappa B sites. Like RL/IF-1, several members of the NF-kappa B and rel family of transcription factors are immediate-early genes in regenerating liver and mitogen-treated cells. We examined changes in kappa B site binding activity during liver regeneration and discovered a rapidly induced novel kappa B site-binding complex designated PHF [posthepatectomy factor(s)]. PHF is induced over 1,000-fold within minutes posthepatectomy in a protein synthesis-independent manner, with peak activity at 30 min, and is not induced by sham operation. PHF is distinct from p50-p65 NF-kappa B, which is present only in the inactive form in liver posthepatectomy. Although early PHF complexes do not interact strongly with anti-p50 antibodies...

Mechanical loading and control of breathing in patients with severe chronic obstructive pulmonary disease.

Duranti, R.; Misuri, G.; Gorini, M.; Goti, P.; Gigliotti, F.; Scano, G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1995 EN
Relevância na Pesquisa
26.26%
BACKGROUND--High neural drive to the respiratory muscles and rapid and shallow breathing are frequently observed in patients with chronic obstructive pulmonary disease (COPD), and both mechanical and chemical factors are thought to play a part. However, the interrelation between these factors and the modifications in the control of breathing are not clearly defined. The effects of an acute decrease in mechanical load by the administration of a high dose of a beta 2 agonist were studied. METHODS--Nine spontaneously breathing patients with severe COPD took part in the study. Criteria for entry were FEV1 of < 40% of predicted and an improvement in FEV1 of < 200 ml after inhalation of 400 micrograms fenoterol. The following parameters were measured: lung volumes, tidal volume (VT), respiratory frequency (Rf), maximal pleural pressure during a sniff manoeuvre (PPLmax), pleural pressure swings (PPLsw), lung resistance (RL), RL/PPLmax ratio, and surface electromyographic activity (EMG) of diaphragm (EDI) and parasternal (EPS) muscles. Arterial oxygen saturation (SaO2), end tidal carbon dioxide pressure (PETCO2), and the electrocardiogram were also monitored. Each variable was measured under control conditions and 20 and 40 minutes after the inhalation of 800 micrograms fenoterol. In five patients the effects of placebo were also studied. RESULTS--Fenoterol resulted in an increase in FEV1 and decrease in FRC. SaO2 did not change...

The lack of RNA-dependent protein kinase enhances susceptibility of mice to genital herpes simplex virus type 2 infection

Carr, Daniel J J; Wuest, Todd; Tomanek, Lisa; Silverman, Robert H; Williams, Bryan R G
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /08/2006 EN
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26.2%
Mice deficient in RNA-dependent protein kinase (PKR–/–) or deficient in PKR and a functional 2′,5′-oligoadenylate synthetase (OAS) pathway (PKR/RL–/–) are more susceptible to genital herpes simplex virus type 2 (HSV-2) infection than wild-type mice or mice that are deficient only in a functional OAS pathway (RL–/–) as measured by survival over 30 days. The increase in susceptibility correlated with an increase in virus titre recovered from vaginal tissue or brainstem of infected mice during acute infection. There was also an increase in CD45+ cells and CD8+ T cells residing in the central nervous system of HSV-2-infected PKR/RL–/– mice in comparison with RL–/– or wild-type control animals. In contrast, there was a reduction in the HSV-specific CD8+ T cells within the draining lymph node of the PKR/RL–/– mice. Collectively, activation of PKR, but not of OAS, contributes significantly to the local control and spread of HSV-2 following genital infection.

In vivo tumouricidal effects of LAD-1 monoclonal antibody on murine RL-male-1 lymphoma mediated by enhanced phagocytosis

Ito, M; Omoto, S; Kato, Y; Hayashi, T; Mori, N; Fujii, Y R
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /07/2005 EN
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36.2%
We have reported previously that the LAD-4 monoclonal antibody (mAb) directed against a fibronectin receptor (FNR) on RL-male-1 T lymphoma cells in BALB/c mice partially inhibited their migration to the liver. In the present study, we examined the mechanism by which another anti-FNR mAb, LAD-1, exerts its antitumourigenic effects. Administration of LAD-1 significantly prolonged survival of BALB/c mice challenged previously with RL-male-1 cells. LAD-1 enhanced phagocytosis of RL-male-1 cells by hepatic macrophages and clodronate-mediated macrophage depletion abrogated the antitumour activity of LAD-1. In vitro experiments revealed that a pan-caspase inhibitor, zVAD-fmk, did not affect the ability of LAD-1 to inhibit the proliferation of RL-male-1 cells. These data suggest that the antitumour effects of LAD-1 may be dependent on stimulation of tumour cell phagocytosis and are apoptosis-independent. Thus, LAD-1-induced phagocytosis of lymphoma cells by hepatic macrophages in mice may, at least in part, be responsible for the prolonged survival of the mice.

Correlation between chemical structure and biological activities of Porphyromonas gingivalis synthetic lipopeptide derivatives

Makimura, Y; Asai, Y; Taiji, Y; Sugiyama, A; Tamai, R; Ogawa, T
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em /10/2006 EN
Relevância na Pesquisa
26.23%
We recently separated a PG1828-encoded triacylated lipoprotein (Pg-LP), composed of two palmitoyl and one pentadecanoyl groups at the N-terminal of glycerocysteine from Porphyromonas gingivalis, a periodontopathic bacteria, and found that Pg-LP exhibited definite biological activities through Toll-like receptor (TLR) 2. In the present study, we synthesized 12 different Pg-LP N-terminal peptide moieties (PGTP) using four combinations of glyceryl (R and S) and cysteinyl (l and d) stereoisomers, and three different acyl group regioisomers, N-pentadecanoyl derivative (PGTP1), S-glycero 2-pentadecanoyl derivative (PGTP2) and S-glycero 3-pentadecanoyl derivative (PGTP3). All the PGTP compounds (RL, SL, SD, RD) tested showed TLR2-dependent cell activation. The activating capacities of the PGTP-R compounds were more potent than those of the PGTP-S compounds, whereas there were no differences between the PGTP-L and -D compounds. Furthermore, the production of interleukin (IL)-6 following stimulation with the PGTP1-RL, PGTP2-RL and PGTP3-RL compounds was impaired in peritoneal macrophages from TLR2 knock-out (KO), but not those from TLR1 KO or TLR6 KO mice. These results suggest that P. gingivalis triacylated lipopeptides are capable of activating host cells in a TLR2-dependent and TLR1-/TLR6-independent manner...

Studies on insecticide-resistant anophelines: 2. Chromosome arrangements in laboratory-developed DDT-resistant strains of Anopheles atroparvus

Mosna, E.; Palmieri, C.; Ascher, K. R. S.; Rivosecchi, L.; Neri, I.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //1959 EN
Relevância na Pesquisa
26.26%
The development of several DDT-resistant strains of Anopheles atroparvus is described. They were selected by larval treatment only (RL), selection of larval and adult females (RLAF), and selection of adult females and males (RAFM). Their rate of DDT-resistance was measured in the larval and adult states (mainly in the 32nd generation). The results were compared with those of a dieldrin-selected strain (R/dieldrin) and several normal and semi-normal reference strains. In the larval assay DDT-resistance was of the following order: RL>RLAF>RAFM>R/dieldrin. Topical application to adults gave: RLAF>(RL?)>RAFM>R/dieldrin; while adult tarsal contact gave: RAFM>RLAF>RL>R/dieldrin These different orders of resistance are discussed.

Tachykinins contribute to the acute airways response to allergen in sheep actively sensitized to Ascaris suum

Reynolds, P.; Rice, A.; Reynolds, A.; Thornton, A.; Holmes, M.; Scicchitano, R.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Artigo de Revista Científica
Publicado em //1997 EN
Relevância na Pesquisa
26.2%
Tachykinins, found in sensory nerves, have effects in the airways which suggest that they may contribute to the pathogenesis of asthma. We aimed to find evidence for tachykinin involvement in the immediate airway response to allergen in a sheep model of experimental asthma. Twenty-four sheep were actively sensitized to Ascaris suum, then challenged with nebulized Ascaris extract in a dose-response fashion. Change in lung resistance (RL) in response to challenge was measured. Responder sheep (those with an increase in RL of > or = 100% over baseline) that had reproducible responses over three challenges were identified (n = 4 sheep) and a PC100 (number of breaths of extract required to induce a 100% increase in RL) was determined. The effect of the neutral endopeptidase inhibitor phosphoramidon, the NK-1 receptor-specific antagonist CP 96, 345 and capsaicin desensitization on the RL response to Ascaris challenge was then assessed. Administration of phosphoramidon before Ascaris decreased the PC100 to 31 +/- 7% of the PC100 seen with Ascaris alone (P < 0.05), whereas CP 96,345 and capsaicin desensitization increased the PC100 to 285 +/- 41% and 555 +/- 93% respectively (P < 0.05 for both). These findings suggest that endogenous tachykinins are released in response to allergen challenge and that they contribute to the immediate increase in RL.; Reynolds...

Apoptosis as a prognostic marker in prediction of renal injury, after acute bleeding and volume replacement with HES 130/0.4 or Ringer solution, in a pig model

Cruz, R.; Vala, H.; Machado, A.; Venâncio, C.; Mesquita, J.; Silva, A.; Ortiz, A. L.; Ferreira, D.
Fonte: Instituto Politécnico de Viseu Publicador: Instituto Politécnico de Viseu
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 ENG
Relevância na Pesquisa
36.15%
Objectives: The aim of this study is to identify and quantify apoptosis in renal tissue, using a biochemical marker (TUNEL) in a pig haemorrhagic model, after intravascular volume replacement with Ringer's lactate RL) or Hydroxyethylstarch (HES) 130/0.4) solutions. Methods: 18 Large White pigs underwent total intravenous anaesthesia (TIVA) with propofol and remifentanil. 25 ml/kg of arterial blood were removed from the femoral artery. Volume was replaced, RL, in group1 (n=6) and HES 130/0.4, in group2 (n=6), 20 min after bleeding. The control group did not face bleeding and volume reposition. One hour after volume replacement, pigs were euthanized with intravenous KCl, and renal tissue samples were taken for several studies, including immunohistochemically with in situ TUNEL method for apoptosis detection. ANOVA was used to compare data between groups. Results: In all groups apoptosis was, as expected, mainly detected in epithelial tubular cells of the proximal and distal convoluted tubules, in the loop of Henle and in the epithelium of collecting tubules, however the number of apoptotic cells per mm2 was lower in group 1 (35.68 apoptotic cells/mm2), when compared with group 2 (67.94 apoptotic cells/mm2) and the control group (146.34 apoptotic cells/mm2). The level of apoptosis was significantly higher in Ringer Lactate group...

Isolation of an allele of reeler by insertional mutagenesis.

Miao, G G; Smeyne, R J; D'Arcangelo, G; Copeland, N G; Jenkins, N A; Morgan, J I; Curran, T
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 08/11/1994 EN
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26.32%
Reeler (rl) is an autosomal recessive mutation that affects migration of postmitotic neurons in the mouse central nervous system. The reeler (rl/rl) mouse displays a disruption of laminar structures in both the cerebellum and the forebrain and it exhibits tremors, dystonia, and ataxia. The molecular basis of the reeler phenotype is unknown because the gene involved has not yet been identified. We report here the isolation and characterization of an allele of rl, reelertransgene (rltg). This allele was generated by the fortuitous insertion of a transgene, supfos (sf), into the mouse rl locus. Crosses between rl/+ and rltg/+ mice yielded offspring that exhibited the reeler phenotype, indicating that rl and rltg are allelic. We cloned the genomic sequences flanking the transgene insertion site from the rltg/rltg mouse genome. Chromosomal mapping studies revealed that the 5' flanking cellular sequence maps to a locus, D5Gmr1, that lies in a region of mouse chromosome 5 that also contains the rl locus. Southern blot analysis using a probe derived from the D5Gmr1 locus revealed no gross structural rearrangement in the rl locus. Thus, unlike the two rl alleles described previously, rltg provides a molecular probe that can now be used to identify and isolate the rl gene.

XMM-Newton spectroscopy of an X-ray selected sample of RL AGNs

Galbiati, E.; Caccianiga, A.; Maccacaro, T.; Braito, V.; Della Ceca, R.; Severgnini, P.; Brunner, H.; Lehmann, I.; Page, M. J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/10/2004
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36.28%
This paper presents the X-ray spectroscopy of an X-ray selected sample of 25 radio-loud (RL) AGNs extracted from the XBSS sample. The main goal is to study the origin of the X-ray spectral differences usually observed between radio-loud and radio-quiet (RQ) AGNs. To this end, a comparison sample of 53 RQ AGNs has been also extracted from the same XBSS sample and studied together with the sample of RL AGNs. We have focused the analysis on the distribution of the X-ray spectral indices of the power-law component that models the large majority of the spectra in both samples. We find that the mean X-ray energy spectral index is very similar in the 2 samples and close to alpha_X~1. However, the intrinsic distribution of the spectral indices is significantly broader in the sample of RL AGNs. In order to investigate the origin of this difference, we have divided the RL AGNs into blazars and ``non-blazars'', on the basis of the available optical and radio information. We find strong evidence that the broad distribution observed in the RL AGN sample is mainly due to the presence of the blazars. Furthermore, within the blazar class we have found a link between the X-ray spectral index and the value of the radio-to-X-ray spectral index suggesting that the observed X-ray emission is directly connected to the emission of the relativistic jet. This trend is not observed among the ``non-blazars'' RL AGNs. This favours the hypothesis that...

Binding cooperativity of membrane adhesion receptors

Krobath, Heinrich; Rozycki, Bartosz; Lipowsky, Reinhard; Weikl, Thomas R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/06/2009
Relevância na Pesquisa
26.26%
The adhesion of cells is mediated by receptors and ligands anchored in apposing membranes. A central question is how to characterize the binding affinity of these membrane-anchored molecules. For soluble molecules, the binding affinity is typically quantified by the binding equilibrium constant K3D in the linear relation [RL] = K3D [R][L] between the volume concentration [RL] of bound complexes and the volume concentrations [R] and [L] of unbound molecules. For membrane-anchored molecules, it is often assumed by analogy that the area concentration of bound complexes [RL] is proportional to the product [R][L] of the area concentrations for the unbound receptor and ligand molecules. We show here (i) that this analogy is only valid for two planar membranes immobilized on rigid surfaces, and (ii) that the thermal roughness of flexible membranes leads to cooperative binding of receptors and ligands. In the case of flexible membranes, the area concentration [RL] of receptor-ligand bonds is proportional to the square of [R][L] for typical lengths and concentrations of receptors and ligands in cell adhesion zones. The cooperative binding helps to understand why different experimental methods for measuring the binding affinity of membrane-anchored molecules have led to values differing by several orders of magnitude.; Comment: 9 pages...

Radio Loud AGN in the Context of the Eigenvector 1 Parameter Space

Sulentic, J. W.; Zamfir, S.; Marziani, P.; Bachev, R.; Calvani, M.; Dultzin-Hacyan, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/09/2003
Relevância na Pesquisa
26.31%
We consider the properties of radio-loud (RL) AGN in the context of the Eigenvector 1 (E1) parameter space. RL sources show a restricted E1 parameter space occupation relative to the radio-quiet (RQ) majority. The Fanaroff-Riley II ``parent population'' of relatively un-boosted RL sources (median radio/optical flux ratio ~490) shows the most restricted occupation. RL sources have different broad line properties (and inferred black hole masses and Eddington ratios). FWHM H_beta for the broad line component in RL sources are at least twice as large as the RQ majority. The average broad FeII emission line strength is also about half that for RQ sources. Our sample suggests that the RL cutoff occurs near R_k=70 or logP(6cm)=32.0 ergs/s/Hz. Sources below this cutoff are RQ although we cannot rule out the existence of a distinct intermediate population. We show that the Doppler boosted core-dominated RL sources (median flux ratio ~1000) lie towards smaller FWHM(H_beta_bc) and stronger FeII in E1 as expected if the lines arise in an accretion disk. Our subsample of superluminal sources, with orientation inferred from the synchrotron self Compton model, reinforce this general E1 trend and allow us to estimate the role of source orientation in driving E1 domain occupation.; Comment: 9 pages...

Optical/UV/X-ray Insights into the RL--RQ Dichotomy

Sulentic, J.; Zamfir, S.; Marziani, P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/10/2009
Relevância na Pesquisa
26.33%
We explore the relationship between radio-loud (RL) and radio-quiet (RQ) quasars using a set of optical/UV/X-ray measures that are quite independent of radio measures. We find RL sources to show larger average FWHM H-beta, weaker FeII emission, no soft X-ray excess and no CIV blueshift - all characteristics manifested by a large fraction of RQ quasars (that we call Population A). We find that log L (1.4Ghz) = 31.6 [ergs/s/Hz] (or R=70) is the lower limit for RL quasars showing FRII morphology. We find no evidence for a hidden FRII population below this level. We conclude that RL sources are a distinct quasar population that may also include 30-40 percent of RQ sources which apparently show similar geometry and kinematics (what we call Population B). This RQ overlap, if not coincidental, may include inactive RL quasars as well as quasars with geometry/kinematics similar to RL sources but where RL activity is inhibited in some way (e.g. host morphology, BH spin).; Comment: To appear in the Proceedings of "Accretion and Ejection in AGN: A Global View" held in Como, Italy June 22-26, 2009. Editors: L. Maraschi, G. Ghisellini, R. Della Ceca and F. Tavecchio

Accurate mass ratio and heating effects in the dual-line millisecond binary pulsar in NGC 6397

Ferraro, F. R.; Sabbi, E.; Gratton, R.; Possenti, A.; D'Amico, N.; Bragaglia, A.; Camilo, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/01/2003
Relevância na Pesquisa
35.82%
By means of high-resolution spectra we have measured radial velocities of the companion (hereafter COM J1740-5340) to the eclipsing millisecond pulsar PSR J1740-5340 in the Galactic globular cluster NGC 6397. The radial-velocity curve fully confirms that COM J1740-5340 is orbiting the pulsar and enables us to derive the most accurate mass ratio (M_ PSR/M_COM=5.85+/-0.13) for any non-relativistic binary system containing a neutron star. Assuming a pulsar mass in the range 1.3-1.9 Msun, the mass of COM J1740-5340 spans the interval 0.22-0.32 Msun, the inclination of the system is constrained within 56 deg <= i <= 47 deg and the Roche lobe radius is r_RL ~ 1.5-1.7 Rsun. A preliminary chemical abundance analysis confirms that COM J1740-5340 has a metallicity compatible with that measured for other stars in this metal-poor globular, but the unexpected detection of strong He I absorption lines implies the existence of regions at T>10,000 K, significantly warmer than the rest of the star. The intensity of this line correlates with the orbital phase, suggesting the presence of a region on the companion surface, heated by the millisecond pulsar flux.; Comment: 13 pages, 3 figures, in press on ApJ Letters (Feb. 10)

Fotocontrol de la productividad y elongación detallos de tres cultivares de Rosa x hybrida L. bajocubiertas de polietileno fotoselectivas

Mascarini,Libertad; Lorenzo,Gabriel A; Burgos,Marcelo L
Fonte: Revista de la Facultad de Ciencias Agrarias. Universidad Nacional de Cuyo Publicador: Revista de la Facultad de Ciencias Agrarias. Universidad Nacional de Cuyo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 ES
Relevância na Pesquisa
46.18%
Se evaluaron los cambios en la radiación transmitida a través de films fotoselectivos (FS) fluorescentes y el impacto de estos cambios sobre la producción de tres cultivares de rosa para corte Fuego Negro, Maroussia y Anna. Se observó que los FS nuevos o expuestos a la radiación solar vs. noFS disminuyen la transmisión de radiación azul (A) (-28,4 a -32,9%, respectivamente), incrementan el R produciendo una relación R:RL mayor (+3,6%), si bien transmiten algo menos de radiación fotosintéticamente activa que los noFS nuevos. El número de rosas producidas fue significativamente mayor bajo el FS vs. noFS en los tres cv (+24, +32 y +36% en Anna, Fuego Negro y Maroussia, respectivamente), con un peso fresco y seco (PF y PS) significativamente mayor y tallos florales más largos en Anna y Maroussia (50,69 y 43,91 cm vs. 38,91 y 40,04 cm en invierno y primavera, respectivamente), y pimpollos significativamente más largos y de mayor PF y PS en los tres cv. Mayor relación R:RL y menor UV-A y A en la radiación transmitida por films FS aumentaron la cantidad y calidad de determinados cultivares de rosas mostrando una alternativa a los reguladores químicos de crecimiento.