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1.
Phys Rev Lett ; 107(25): 251301, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22243065

RESUMO

This Letter aims at showing that the observation of evaporating black holes should allow the usual Hawking behavior to be distinguished from loop quantum gravity (LQG) expectations. We present a full Monte Carlo simulation of the evaporation in LQG and statistical tests that discriminate between competing models. We conclude that contrarily to what was commonly thought, the discreteness of the area in LQG leads to characteristic features that qualify evaporating black holes as objects that could reveal quantum gravity footprints.

2.
Phys Rev Lett ; 102(8): 081301, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19257730

RESUMO

The primordial spectrum of cosmological tensor perturbations is considered as a possible probe of quantum gravity effects. Together with string theory, loop quantum gravity is one of the most promising frameworks to study quantum effects in the early universe. We show that the associated corrections should modify the potential seen by gravitational waves during the inflationary amplification. The resulting power spectrum should exhibit a characteristic tilt. This opens a new window for cosmological tests of quantum gravity.

3.
C R Acad Sci III ; 316(8): 716-20, 1993 Aug.
Artigo em Francês | MEDLINE | ID: mdl-8044695

RESUMO

It is proposed to use all the presently available molecular, ultrastructural, biological and ecological data on ciliates for the new classification of this group of protists. On the basis of the cortical organization and the mode of cilia anchoring as well as the degree of conservation of the cortical pattern during the process of morphogenesis, eleven classes (Karyorelictea, Heterotrichea, Hypotrichea, Oligotrichea, Plagiopylea, Colpodea, Litostomatea, Vestibuliferea, Phyllopharyngea, Nassophorea and Oligohymenophorea) have been distinguished. These classes, in turn, were, according to the "shell theory" of Fleury and coworkers (1992), grouped into three subphyla: Tubulicorticata (presence of the cortical microtubular lattices), Filicorticata (characteristic ecto-endoplasmic microfibrillar boundary) and Epiplasmata (presence of a sub-membraneous epiplasmic layer).


Assuntos
Cilióforos/classificação , Animais
4.
Eur J Protistol ; 24(3): 225-37, 1989 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-23195658

RESUMO

This ultrastructural study of the entodiniomorphid Troglodytella gorillae provides information on the constitution of the cortex, which is composed of the plasma membrane, a thick epiplasm, microtubules, and a microfibrillar ecto-endoplasmic limit (cortex type I). This observation allows us to group the family Troglodytellidae with the families Cycloposthiidae and Ophryoscolecidae. These 3 families should be separated from the families Tripalmariidae and Spirodiniidae which possess a more complex cortex, with longitudinal dense tracts inserted between the microtubular layer and the microfibrillar ecto-endoplasmic limit (type II). Terminology is discussed.

6.
Reprod Nutr Dev (1980) ; 26(1B): 147-59, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3517985

RESUMO

The rumen is a strictly anaerobic ecosystem colonized by an extremely dense microflora and microfauna. These populations are composed of a grand variety of bacterial and protozoal species. Their cohabitation allows observation of most of the known stages of communal life. The different hydrolytic, fermentative and methanogenic activities of these populations ensure the efficient degradation of cell wall constituent in forages (cellulose, hemicellulose, pectin) ingested by ruminants.


Assuntos
Bactérias Anaeróbias/fisiologia , Rúmen/microbiologia , Animais , Artiodáctilos , Parede Celular/metabolismo , Celulose/metabolismo , Eucariotos/fisiologia , Ácidos Graxos/metabolismo , Fermentação , Glucose/metabolismo , Hidrogênio/metabolismo , Hidrólise , Lactatos/metabolismo , Ácido Láctico , Metano/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Rúmen/parasitologia
8.
J Protozool ; 27(1): 37-58, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6989987

RESUMO

The subkingdom Protozoa now inclues over 65,000 named species, of which over half are fossil and approximately 10,000 are parasitic. Among living species, this includes approximately 250 parasitic and 11,300 free-living sarcodines (of which approximately 4,600 are foraminiferids); approximately 1,8000 parasitic and 5,100 free-living flagellates; approximately 5,600 parasitic "Sporozoa" (including Apicomplexa, Microspora, Myxospora, and Ascetospora); and approximately 2,5000 parasitic and 4,700 free-living ciliates. There are undoubtedly thousands more still unnamed. Seven phyla of PROTOZOA are accepted in this classification--SARCOMASTIGOPHORA, LABYRINTHOMORPHA, APICOMPLEXA, MICROSPORA, ASCETOSPORA, MYXOSPORA, and CILIOPHORA. Diagnoses are given for these and for all higher taxa through suborders, and reporesentative genera of each are named. The present scheme is a considerable revision of the Society's 1964 classification, which was prepared at a time when perhaps 48,000 species had been named. It has been necessitated by the acquisition of a great deal of nex taxonomic information, much of it through electron microscopy. It is hoped that the present classification incorporatesmost of the major changes that will be made for some time, and that it will be used for many years by both protozoologist and non-protozoologists.


Assuntos
Eucariotos/classificação , Animais , Bibliografias como Assunto , Terminologia como Assunto
12.
C R Acad Hebd Seances Acad Sci D ; 282(8): 735-8, 1976 Feb 23.
Artigo em Francês | MEDLINE | ID: mdl-817834

RESUMO

With a parorale of "stichodyade-type", and three adoral organelles like peniculus, the genus Cyclogramma may be included in the Oligohymenophora class, subclass Hymenostomata. The presence of a basket as cytopharyngeal apparatus, and the semi-autonomous stomatogenesis justify, for this genus, the establishment of the new order Parahymenostomatida.


Assuntos
Cilióforos/classificação , Cílios/ultraestrutura , Cilióforos/ultraestrutura , Microscopia Eletrônica , Organoides/ultraestrutura
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