Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

On e-continuous functions and related results

100%

Xie T. , Li H.

tom Nr 50

121--136

In this paper, characterizations and properties of e-continuous functions are given. Moreover, Urysohn's Lemma on e-normal spaces is proved.

Associated growth of C3 and C4 desert plants helps the C3 species at the cost of the C4 species

70%

Su P. , Yan Q. , Xie T. , Zhou Z. , Gao S.

nr 6

C₃ desert plant Reaumuria soongorica (RS-C₃) and C₄ desert plant Salsola passerina (SP-C₄) may exist either in individual or in associated communities. Carbon isotope composition, leaf water potential, gas exchange and chlorophyll fluorescence characteristics of the individual and associated communities were compared with reveal, whether the associated growth represent an advantage under harsh habitat. The results showed that the δ¹³Cvalues of leaves ofRS-C₃ and SP-C₄ across different habitats fluctuated, respectively, from-24 to-27 ‰ and from-14 to-16 ‰. Leafwater potential of RS-C₃ was lower than SP-C₄ all day long, growing either individually or associated with the C₃ plant. When associated with the C₄ plant, the net photosynthetic rate of the RS-C₃ increased, and the photosynthetic rate of the partner SP-C₄ decreased. The transpiration rates of the associatedRS-C₃ and SP-C₄ were both lower than in their individual colonies. In associated communities, in RS-C₃, the maximal photochemical efficiency, the effective photochemical efficiency, the relative electron transport rate, the photochemical quenching of PS II increased, and the non-photochemical quenching of PS II decreased; all these parameters changed oppositely in the SP-C₄ plant.This shows that, in the associated community, the C₄ plants might facilitate adaptation of the RS-C₃, while SP-C₄ plant can adapt to the harsh environment through their own specialties. The association favored the expression of natural photosynthetic characteristics and survival of RS-C₃, while retarded the growth of SP-C₄. Associated growth decreases the transpiration rate of the whole community; it is conducive to improve its water use efficiency.

A new basal actinopterygian fish from the Anisian (Middle Triassic) of Luoping, Yunnan Province, Southwest China

51%

Wen W. , Zhang Q.-Y. , Hu S.-X. , Zhou C.-Y. , Xie T. , Huang J.-Y. , Chen Z. Q. , Benton M. J.

nr 1

The new neopterygian fish taxon Luoxiongichthys hyperdorsalis gen. et sp. nov. is established on the basis of five specimens from the second member of the Guanling Formation (Anisian, Middle Triassic) from Daaozi Quarry, Luoping, Yunnan Province, Southwest China. The new taxon is characterized by the following characters: triangular body outline with a distinct apex located between skull and dorsal fin; free maxilla; slender preopercular almost vertical; three suborbitals; at least eight strong branchiostegals with tubercles and comb−like ornamentation on the anterior margin; clavicles present; two postcleithra; ganoid scales covered by tubercles and pectinate ornamentation on the posterior margin with peg−and−socket structure; hemiheterocercal tail slightly forked. Comparison with basal actinopterygians reveals that the new taxon has parasemionotid−like triangular symplectics, but a semionotid opercular system. Cladistic analysis suggests that this new genus is a holostean, and either a basal halecomorph or basal semionotiform.