Search results for "sequence"

Pre-main-sequence stars older than 8 Myr in the Eagle nebula

2013

The enigmatic young brown dwarf binary FU Tau: accretion and activity

2010

FU Tau belongs to a rare class of young, wide brown dwarf binaries. We have resolved the system in a Chandra X-ray observation and detected only the primary, FU Tau A. Hard X-ray emission, presumably from a corona, is present but, unexpectedly, we detect also a strong and unusually soft component from FU Tau A. Its X-ray properties, so far unique among brown dwarfs, are very similar to those of the T Tauri star TW Hya. The analogy with TW Hya suggests that the dominating soft X-ray component can be explained by emission from accretion shocks. However, the typical free-fall velocities of a brown dwarf are too low for an interpretation of the observed X-ray temperature as post-shock region. O…

Mass accretion to young stars triggered by flaring activity in circumstellar discs

2011

Young low-mass stars are characterized by ejection of collimated outflows and by circumstellar discs which they interact with through accretion of mass. The accretion builds up the star to its final mass and is also believed to power the mass outflows, which may in turn remove the excess angular momentum from the star-disc system. However, although the process of mass accretion is a critical aspect of star formation, some of its mechanisms are still to be fully understood. A point not considered to date and relevant for the accretion process is the evidence of very energetic and frequent flaring events in these stars. Flares may easily perturb the stability of the discs, thus influencing th…

Kìnecʹ koncepcìï partnersʹkogo marketingu? Marketing 3.0 či zaklâttâ realʹnostì?

2016

This article provides various marketing concepts and orientation which were aimed at bringing positive and desired social effects for business activities. Nevertheless, in authors view, the theory does not reflect the reality of business practices. Therefore, a number of companies which are making use of aggressive marketing but in fact ignore the consumer needs were presented. This includes, among other things, the following markets: food, electronic one and even pharmaceutical. It seems that this is caused by monopolization process of global economy.

Importance de la variabilité fonctionnelle intraspécifique des adventices en réponse aux pratiques culturales et aux conditions climatiques

2016

EAGESTADCT1; Importance de la variabilité fonctionnelle intraspécifique des adventices en réponse aux pratiques culturales et aux conditions climatiques. Ecologie des Communautés Végétales (ECOVEG 12)

Cloning and Targeted Deletion of the Mouse Fetuin Gene

1998

We proposed that the alpha2-Heremans Schmid glycoprotein/fetuin family of serum proteins inhibits unwanted mineralization. To test this hypothesis in animals, we cloned the mouse fetuin gene and generated mice lacking fetuin. The gene consists of seven exons and six introns. The cystatin-like domains D1 and D2 of mouse fetuin are encoded by three exons each, whereas a single terminal exon encodes the carboxyl-terminal domain D3. The promoter structure is well conserved between rat and mouse fetuin genes within the regions shown to bind transcription factors in the rat system. Expression studies demonstrated that mice homozygous for the gene deletion lacked fetuin protein and that mice heter…

Rat tyrosine kinase inhibitor shows sequence similarity to human α2-HS glycoprotein and bovine fetuin

1991

Human alpha 2-HS glycoprotein and bovine fetuin, abundant proteins of fetal plasma, are structural members of the fetuin family within the cystatin superfamily. They are characterized by the presence of two N-terminally located cystatin-like units and a unique C-terminal sequence segment not present in the other members of the cystatin superfamily. Search for related sequences revealed that the natural inhibitor of the insulin receptor tyrosine kinase [Auberger, Falquerho, Contreres, Pages, Le Cam, Rossi & Le Cam (1989) Cell (Cambridge, Mass.) 58, 631-640] shows sequence similarity to the mammalian fetuins. The sequence identity between rat tyrosine kinase inhibitor, human alpha 2-HS gl…

Failure to differentiate Cryptosporidium parvum from C. meleagridis based on PCR amplification of eight DNA sequences.

1998

ABSTRACT In order to determine the specificities of PCR-based assays used for detecting Cryptosporidium parvum DNA, eight pairs of previously described PCR primers targeting six distinct regions of the Cryptosporidium genome were evaluated for the detection of C. parvum , the agent of human cryptosporidiosis, and C. muris , C. baileyi , and C. meleagridis , three Cryptosporidium species that infect birds or mammals but are not considered to be human pathogens. The four Cryptosporidium species were divided into two groups: C. parvum and C. meleagridis , which gave the same-sized fragments with all the reactions, and C. muris and C. baileyi , which gave positive results with primer pairs targ…

Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system

2007

Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I…

Okadaic Acid, an Apoptogenic Toxin for Symbiotic/Parasitic Annelids in the Demosponge Suberites domuncula

2006

ABSTRACT The role of okadaic acid (OA) in the defense system of the marine demosponge Suberites domuncula against symbiotic/parasitic annelids was examined. Bacteria within the mesohyl produced okadaic acid at concentrations between 32 ng/g and 58 ng/g of tissue (wet weight). By immunocytochemical methods and by use of antibodies against OA, we showed that the toxin was intracellularly stored in vesicles. Western blotting experiments demonstrated that OA also existed bound to a protein with a molecular weight of 35,000 which was tentatively identified as a galectin (by application of antigalectin antibodies). Annelids that are found in S. domuncula undergo apoptotic cell death. OA is one ca…