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1.
(1) The polymorphic phase behaviour of aqueous dispersions of various synthetic phosphatidylethanolamines, both singly and in mixtures, has been investigated by 31P-NMR. (2) PE remains in the lamellar phase up to 90°C. PE exhibits a lamellar to hexagonal (HII) transition between 60°C and 63°C. For PE, the lamellar to hexagonal (HII) transition occurs between 7 and 12°C, whereas for PE, the hexagonal (HII) phase is the preferred structure above ?15°C. (3) Mixtures of PE and PE exhibit near-ideal miscibility behaviour. For mixtures of PE and PE there is evidence of fluid-solid immiscibility at temperatures below the gel-liquid crystalline transition temperature of the PE component. Mixtures of PE and PE exhibit complex phase behaviour involving limited fluid-solid immiscibility at low temperatures and formation of a phase allowing isotropic motional averaging at higher temperatures. (4) 31P-NMR provides a graphic method for investigating the miscibility properties of mixed PE systems. 相似文献
2.
Clusters [MoS4Ag3(PPh3)3{S2P(OPri)2}] (1), [WS4Ag3(PPh3)3{S2P(OPri)2}] (2) and [WOS3Ag3(PPh3)3{S2P(OPri)2}] (3) were synthesized by the reaction of (NH4)2MoS4/(NH4)2WS4, (NH4)2WOS3 with Ag[S2P(OPri)2]. Their structures have been characterized by X-ray diffraction. The clusters consist of a distorted tetrahedral MS4 (or MOS3) (M = Mo, W) with three Ag atoms and three sulfur atom bridges (Fig. 1), and resemble roughly that of cubane-like clusters. The nonlinear optical (NLO) properties were studied with an 8 ns pulsed laser at 532 nm. Its optical response to the incident light exhibits good optical absorptive and refractive effects, with α2 = 1.56 × 10−10 m W−1, n2 = 3.87 × 10−17 m2 W−1 for cluster 1; α2 = 1.33 × 10−10 m W−1, n2 = 6.52 × 10−17 m2 W−1for cluster 2; and α2 = 2.54 × 10−10 m W−1, n2 = 4.07 × 10−17 m2 W−1 for cluster 3 for a 1.56 × 10−4 mol dm−3 CH2Cl2 solution. 相似文献
3.
Javier Sanzol 《Tree Genetics & Genomes》2009,5(3):393-405
Sexual self-incompatibility in European pear (Pyrus communis L.) is controlled by a single locus (S-locus) encoding a polymorphic stylar ribonuclease (S-RNase) that is responsible for the female function in pollen–pistil recognition. In this study, genomic DNA sequences corresponding
to five new S-RNase alleles (named S
20
, S
21
, S
22
, S
23
, and S
24
) and to S
m
were characterized in European pear cultivars. Re-sequencing S
q
from ‘General Le Clerc’ showed this S-RNase to encode the same protein as S
12
. Based on these findings, a polymerase chain reaction (PCR)-based method was developed for the molecular typing of cultivars
bearing 20 S-RNases (S
1
–S
14
, S
m
, and S
20
–S
24
) using consensus and allele-specific primers. Genomic PCR with consensus primers amplified product sizes characteristic of
the S-RNases S
1
, S
2
, S
4
, S
10
, S
13
, and S
20
. However, the allele groups S
3
/S
12
, S
6
/S
8
/S
11
/S
22
and S
5
/S
7
/S
9
/S
14
/S
m
/S
21
/S
23
/S
24
amplified PCR products of similar size. To discriminate between alleles within these groups, primers to specifically amplify
each S-RNase were developed. Application of this approach in 19 cultivars with published S-alleles allowed re-evaluation of one of the alleles of ‘Passe Crassane,’ ‘Conference,’ and ‘Condo.’ Finally, this method
was used to assign S-genotypes to 37 cultivars. Test crosses confirmed molecular results.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
5.
Elizabeth R. Hawkins Lara Pogson-Manning Christian Jaehnichen Justin J. Meager 《Marine Mammal Science》2020,36(2):500-521
Understanding the social organization of coastal dolphins, particularly those that reside adjacent to major cities and urbanized regions, is important for understanding the vulnerability of populations to human impacts. We investigated the sexual segregation and social dynamics in a population of Australian humpback dolphins (Sousa sahulensis) inhabiting the near-urban embayment of Moreton Bay, Queensland. Over 160 vessel-based surveys, 148 adults were photographically identified. This included 116 assumed females and 32 assumed males. The population was sexually segregated (SSAS = 0.52, p < .001) and individuals preferred to associate with others of the same sex occupying the same spatial area (p < .025). Association indices between paired males were almost double those of females ( , SD = 0.04 and , SD = 0.02, respectively). However, females were more gregarious than males and maintained a larger network of associates based on preferred companionships. The social network was also modular with five clusters identified, and a limited number of individuals had a disproportionate influence on connectivity between clusters. This highly fragmented social network implies that the population may be vulnerable to social disruptions from human impacts. 相似文献
6.
A recombinant putative β-galactosidase from Thermoplasma acidophilum was purified as a single 57 kDa band of 82 U mg−1. The molecular mass of the native enzyme was 114 kDa as a dimer. Maximum activity was observed at pH 6.0 and 90°C. The enzyme
was unstable below pH 6.0: at pH 6 its half-life at 75°C was 28 days but at pH 4.5 was only 13 h. Catalytic efficiencies decreased
as p-nitrophenyl(pNP)-β-d-fucopyranoside (1067) > pNP-β-d-glucopyranoside (381) > pNP-β-d-galactopyranoside (18) > pNP-β-d-mannopyranoside (11 s−1 mM−1), indicating that the enzyme was a β-glycosidase. 相似文献
7.
8.
pH
i
recovery in acid-loaded Ehrlich ascites tumor cells and pH
i
maintenance at steady-state were studied using the fluorescent probe BCECF.Both in nominally HCO
3
–
-free media and at 25 mm HCO
3
–
, the measured pH
i
(7.26 and 7.82, respectively) was significantly more alkaline than the pH
i
. value calculated assuming the transmembrane HCO
3
–
gradient to be equal to the Cl– gradient. Thus, pH
i
in these cells is not determined by the Cl– gradient and by Cl–/HCO
3
–
exchange.pH
i
recovery following acid loading by propionate exposure, NH
4
+
withdrawal, or CO2 exposure is mediated by amiloride-sensitive Na+/H+ exchange in HCO3
– free media, and in the presence of HCO
3
–
(25 mm) by DIDS-sensitive, Na+-dependent Cl–/HCO
3
–
exchange. A significant residual pH
i
recovery in the presence of both amiloride and DIDS suggests an additional role for a primary active H+ pump in pH
i
regulation. pH
i
maintenance at steady-state involves both Na+/H+ exchange and Na+-dependent Cl–/HCO
3
–
exchange.Acute removal of external Cl– induces a DIDS-sensitive, Na+-dependent alkalinization, taken to represent HCO
3
–
influx in exchange for cellular Cl–. Measurements of 36Cl– efflux into Cl–-free gluconate media with and without Na+ and/or HCO
3
–
(10 mm) directly demonstrate a DIDS-sensitive, Na+
dependent Cl–/HCO
3
–
exchange operating at slightly acidic pH
i
(pHo 6.8), and a DIDS-sensitive, Na+-independent Cl–/HCO
3
–
exchange operating at alkaline pH
i
(pH
o
8.2).The excellent technical assistance of Marianne Schiødt and Birgit B. Jørgensen is gratefully acknowledged. The work was supported by the Carlsberg Foundation (B.K.) and by a grant from the Danish Natural Science Foundation (E.K.H. and L.O.S.). 相似文献
9.
10.
In [PtX(PPh3)3]+ complexes (X = F, Cl, Br, I, AcO, NO3, NO2, H, Me) the mutual cis and trans influences of the PPh3 groups can be considered constants in the first place, therefore the one bond Pt-P coupling constants of P(cis) and P(trans) reflect the cis and trans influences of X. The compounds [PtBr(PPh3)3](BF4) (2), [PtI(PPh3)3](BF4) (3), [Pt(AcO)(PPh3)3](BF4) (4), [Pt(NO3)(PPh3)3](BF4) (5), and the two isomers [Pt(NO2-O)(PPh3)3](BF4) (6a) and [Pt(NO2-N)(PPh3)3](BF4) (6b) have been newly synthesised and the crystal structures of 2 and 4·CH2Cl2·0.25C3H6O have been determined. From the 1JPtP values of all compounds we have deduced the series: I > Br > Cl > NO3 > ONO > F > AcO > NO2 > H > Me (cis influence) and Me > H > NO2 > AcO > I > ONO > Br > Cl > F > NO3 (trans influence). These sequences are like those obtained for the (neutral) cis- and trans-[PtClX(PPh3)2] derivatives, showing that there is no dependence on the charge of the complexes. On the contrary, the weights of both influences, relative to those of X = Cl, were found to depend on the charge and nature of the complex. 相似文献
11.
Petr Dolej? 《ZooKeys》2015,(510):5-14
The centipede collection in the National Museum in Prague contains type material of 16 taxa (14 species and two subspecies), of which 15 were described by Luděk J. Dobroruka and one by Karl W. Verhoeff: Allothereua
wilsonae Dobroruka, 1979; Chinobius
alenae Dobroruka, 1980; Lithobius
corrigendus Dobroruka, 1988; Lithobius
creticus Dobroruka, 1977; Lithobius
erythrocephalus
mohelensis Dobroruka, 1959; Lithobius
evae Dobroruka, 1958; Lithobius
magurensis Dobroruka, 1971; Lithobius
purkynei Dobroruka, 1957; Lithobius
tatricus Dobroruka, 1958; Lithobius
tatricus
monounguis Dobroruka, 1958; Monotarsobius
homolaci Dobroruka, 1971; Monotarsobius
krali Dobroruka, 1979; Pachymerium
dilottiae Dobroruka, 1976; Pachymerium
hanzaki Dobroruka, 1976; Scolopendra
aztecorum Verhoeff, 1934 and Strigamia
olympica Dobroruka, 1977. Of these 16 taxa, five were described from the Czech Republic, three from Slovakia and eight from other countries (Greece, Iraq, Kyrgyzstan, Mexico, Nepal, Russia and Uzbekistan). The eight taxa described from the Czech and Slovak Republics are now considered as junior synonyms but the eight taxa described from the other countries are still valid. 相似文献
12.
Inheritance and interactions of incompatibility alleles in the tetraploid sour cherry 总被引:5,自引:0,他引:5
Bosković RI Wolfram B Tobutt KR Cerović R Sonneveld T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(2):315-326
Three progenies of sour cherry (Prunus cerasus) were analysed to correlate self-(in)compatibility status with S-RNase phenotype in this allotetraploid hybrid of sweet and ground cherry. Self-(in)compatibility was assessed in the field and by monitoring pollen tube growth after selfing. The S-RNase phenotypes were determined by isoelectric focusing of stylar proteins and staining for RNase activity and, for the parents, confirmed by PCR. Seedling phenotypes were generally consistent with disomic segregation of S-RNase alleles. The genetic arrangements of the parents were deduced to be ‘Köröser’ (self-incompatible) S 1 S 4 .S B S D , ‘Schattenmorelle’ (self-compatible) S 6 S 13 .S B S B , and clone 43.87 (self-compatible) S 4 S 13 .S B S B , where “.” separates the two homoeologous genomes. The presence of S 4 and S 6 alleles at the same locus led to self-incompatibility, whereas S 13 and S B at homoeologous loci led to self-compatibility. The failure of certain heteroallelic genotypes in the three crosses or in the self-incompatible seedlings indicates that S 4 and S 6 are dominant to S B . However, the success of S 13 S B pollen on styles expressing corresponding S-RNases indicates competitive interaction or lack of pollen-S components. In general, the universal compatibility of S 13 S B pollen may explain the frequent occurrence of S 13 and S B together in sour cherry cultivars. Alleles S B and S D , that are presumed to derive from ground cherry, and S 13 , presumably from sweet cherry, were sequenced. Our findings contribute to an understanding of inheritance of self-(in)compatibility, facilitate screening of progenies for self-compatibility and provide a basis for studying molecular interactions in heteroallelic pollen. 相似文献
13.
Plant regeneration from mesophyll protoplasts of pepper,Capsicum annuum
L. cv. California Wonder has been demonstrated via shoot organogenesis. Protoplasts isolated from fully expanded leaves of
3-week-old axenic shoots when cultured in TM medium supplemented with 1 mg l
−1
NAA, 1 mg l
−1
2,4-D, 0 5 mg l
−1
BAP (CM 1) resulted in divisions with a frequency ranging from 20–25 %. Antioxidant ascorbic acid and polyvinylpyrrolidone
(PVP) in the medium and incubation in the dark helped overcome browning of protoplasts. Microcalli and macrocalli were formed
in TM medium containing 2 mg l
−1
NAA and 0.5 mg l
−1
BAP (CM II) and MS gelled medium containing 2 mg 1
−1
NAA and 0 5 mg 1
−1
BAP (CM III), respectively. Regeneration of plantlets was possible via caulogenesis. Microshoots, 2–5 percallus appeared on
MS gelled medium enriched with 0.5 mg l
−1
IAA, 2mg l
−1
GA and l0mg l
−1
BAP (CM IVc). Rooting of microshoots was obtained on half strength gelled medium containing 1 mg l
−1
NAA and 0.5mg l
−1
BAP. Protoplasts isolated from cotyledons failed to divide and degenerated eventually. 相似文献
14.
As part of an ongoing revision of the family Gonyleptidae, we have identified many species that are synonyms of previously described species or misplaced in this family. This article summarizes these findings, adding previously unavailable information or correcting imprecise observations to justify the presented taxonomic changes.
The following new familial or subfamilial assignments are proposed: Nemastygnus Roewer, 1929 and Taulisa Roewer, 1956 are transferred to Agoristenidae, Agoristeninae; Napostygnus Roewer, 1929 to Cranaidae; Ceropachylinus peruvianus Roewer, 1956 and Pirunipygus Roewer, 1936 are transferred to Gonyleptidae, Ampycinae; Gyndesops Roewer, 1943, Haversia Roewer, 1913 and Oxapampeus Roewer, 1963 are transferred to Gonyleptidae, Pachylinae.
The following generic synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes Mello-Leitão, 1922 = Centroleptes Roewer, 1943; Acrographinotus Roewer, 1929 = Unduavius Roewer, 1929; Gonyleptes Kirby, 1819 = Collonychium Bertkau, 1880; Mischonyx Bertkau, 1880 = Eugonyleptes Roewer, 1913 and Gonazula Roewer, 1930; Parampheres Roewer, 1913 = Metapachyloides Roewer, 1917; Pseudopucrolia Roewer, 1912 = Meteusarcus Roewer, 1913; Haversia Roewer, 1913 = Hoggellula Roewer, 1930.
The following specific synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes singularis (Mello-Leitão, 1935) = Centroleptes flavus Roewer, 1943, syn. n.; Geraeocormobius sylvarum Holmberg, 1887 = Discocyrtus serrifemur Roewer, 1943, syn. n.; Gonyleptellus bimaculatus (Sørensen, 1884) = Gonyleptes cancellatus Roewer,1917, syn. n.; Gonyleptes atrus Mello-Leitão, 1923 = Weyhia brieni Giltay, 1928, syn. n.; Gonyleptes fragilis Mello-Leitão, 1923 = Gonyleptes banana Kury, 2003, syn. n.; Gonyleptes horridus Kirby, 1819 = Collonychium bicuspidatum Bertkau, 1880, syn. n., Gonyleptes borgmeyeri Mello-Leitão, 1932, syn. n., Gonyleptes curvicornis Mello-Leitão, 1932, syn. n., Metagonyleptes hamatus Roewer, 1913, syn. n. and Paragonyleptes simoni Roewer, 1930, syn. n.; Gonyleptes pustulatus Sørensen, 1884 = Gonyleptes guttatus Roewer, 1917, syn. n.; Haversia defensa (Butler, 1876) = Sadocus vallentini Hogg, 1913, syn. n.; Liogonyleptoides minensis (Piza, 1946) = Currala bahiensis Soares, 1972, syn. n.; Megapachylus grandis Roewer, 1913 = Metapachyloides almeidai Soares & Soares, 1946, syn. n.; Mischonyx cuspidatus (Roewer, 1913) = Gonazula gibbosa Roewer, 1930 syn. n.; Mischonyx scaber (Kirby, 1819) = Xundarava holacantha Mello-Leitão, 1927, syn. n.; Parampheres tibialis Roewer, 1917 = Metapachyloides rugosus Roewer, 1917, syn. n.; Parapachyloides uncinatus (Sørensen, 1879) = Goyazella armata Mello-Leitão, 1931, syn. n.; Pseudopucrolia mutica (Perty, 1833) = Meteusarcus armatus Roewer, 1913, syn. n.
The following new combinations are proposed: Acrographinotus ornatus (Roewer, 1929), comb. n. (ex Unduavius); Gonyleptellus bimaculatus (Sørensen, 1884),comb. n. (ex Gonyleptes);Gonyleptes perlatus (Mello-Leitão, 1935), comb. n. (exMoojenia);Mischonyx scaber (Kirby, 1819), comb. n. (ex Gonyleptes); and Neopachyloides peruvianus (Roewer, 1956), comb. n. (ex Ceropachylus).
The following species of Gonyleptidae, Gonyleptinae are revalidated: Gonyleptes atrus Mello-Leitão, 1923 and Gonyleptes curvicornis (Roewer, 1913). 相似文献
15.
Mostafa R. Sharaf Cedric A. Collingwood Hathal M. Al Dhafer Mohammed S. Al mutairi Abdulrahman S. Aldawood 《ZooKeys》2015,(505):51-58
Synonymy of two Arabian Monomorium Mayr, 1855 species is proposed: Monomorium
exiguum Forel, 1894 = Monomorium
desertorum Collingwood & Agosti, 1996, syn. n.; Monomorium
subopacum Smith, 1858 = Monomorium
mintiribe Collingwood & Agosti, 1996, syn. n. A lectotype for Monomorium
venustum Smith, 1858 is designated. Information on nesting habits of Monomorium
exiguum and Monomorium
venustum in the Kingdom of Saudi Arabia are provided for the first time. Recently collected records for Monomorium
exiguum, Monomorium
subopacum, and Monomorium
venustum from the Kingdom of Saudi Arabia and United Arab Emirates are listed. 相似文献
16.
17.
C. Lecomte et J. Pouzat 《Entomologia Experimentalis et Applicata》1985,39(3):295-306
Résumé Chez Diadromus pulchellus WSM et D. collaris Gr., Hyménoptères Ichneumonidés parasitoïdes spécialistes des nymphes d'A. assectella lépidoptère inféodé aux Allium, des EAG sont enregistrés en réponse à l'odeur du poireau sain ou attaqué par les larves du phytophage, odeurs actives par ailleurs sur leur comportement locomoteur (cinèses). Le thiosulfinate de dipropyle (Ti-P2) très spécifique et abondant dans les Allium, et instable, est le mieux perçu par les deux parasitoïdes mais n'a aucun effet locomoteur chez D. pulchellus contrairement aux disulfures et thiosulfonates, plus stables et moins spécifiques. Les propriétés de l'acétate d'éthyle, actif sur l'antenne des deux parasitoïdes, et sur la locomotion de D. pulchellus expliqueraient en partie les activités biologiques du poireau attaqué sur ces parasitoïdes. Des EAG sont aussi obtenus chez les deux espèces avec l'odeur du chou et de composés soufrés plus ou moins spécifiques des Crucifères. Le thiocyanate de méthyle (TCN-M), le plus actif sur l'antenne et seul efficace sur le comportement locomoteur (de D. pulchellus), expliquerait en partie l'installation reconnue de D. collaris sur Plutella maculipennis spécialiste des Crucifères et rend celle de D. pulchelles vraisemblable.L'odeur des larves de dernier stade d'A. assectella est seule efficace sur l'antenne et la locomotion des femelles de D. pulchellus. Les mâles de ce dernier réagissent (EAG, locomotion) à des odeurs de cocons de l'hôte et particulièrement à ceux occupés par une femelle de leur espèce. 相似文献
18.
Kristell Hergoualc’h Ute Skiba Jean-Michel Harmand Catherine Hénault 《Biogeochemistry》2008,89(3):329-345
The objective of this study was to evaluate the effect of N fertilization and the presence of N2 fixing leguminous trees on soil fluxes of greenhouse gases. For a one year period, we measured soil fluxes of nitrous oxide
(N2O), carbon dioxide (CO2) and methane (CH4), related soil parameters (temperature, water-filled pore space, mineral nitrogen content, N mineralization potential) and
litterfall in two highly fertilized (250 kg N ha−1 year−1) coffee cultivation: a monoculture (CM) and a culture shaded by the N2 fixing legume species Inga densiflora (CIn). Nitrogen fertilizer addition significantly influenced N2O emissions with 84% of the annual N2O emitted during the post fertilization periods, and temporarily increased soil respiration and decreased CH4 uptakes. The higher annual N2O emissions from the shaded plantation (5.8 ± 0.3 kg N ha−1 year−1) when compared to that from the monoculture (4.3 ± 0.1 kg N ha−1 year−1) was related to the higher N input through litterfall (246 ± 16 kg N ha−1 year−1) and higher potential soil N mineralization rate (3.7 ± 0.2 mg N kg−1 d.w. d−1) in the shaded cultivation when compared to the monoculture (153 ± 6.8 kg N ha−1 year−1 and 2.2 ± 0.2 mg N kg−1 d.w. d−1). This confirms that the presence of N2 fixing shade trees can increase N2O emissions. Annual CO2 and CH4 fluxes of both systems were similar (8.4 ± 2.6 and 7.5 ± 2.3 t C-CO2 ha−1 year−1, −1.1 ± 1.5 and 3.3 ± 1.1 kg C-CH4 ha−1 year−1, respectively in the CIn and CM plantations) but, unexpectedly increased during the dry season. 相似文献
19.
20.
The present paper reports the graft copolymerization of N-vinylformamide onto sodium carboxymethylcellulose by free radical polymerization using potassium peroxymonosulphate/thiourea redox system in an inert atmosphere. The reaction conditions for maximum grafting have been optimized by varying the reaction variables, including the concentration of N-vinylformamide (12.0 × 10−2–28.0 × 10−2 mol dm−3), potassium peroxymonosulphate (4.0 × 10−3–12.0 × 10−3 mol dm−3), thiourea (1.2 × 10−3–4.4 × 10−3 mol dm−3), sulphuric acid (2.0 × 10−3–10.0 × 10−3 mol dm−3), sodium carboxymethylcellulose (0.2–1.8 g dm−3) along with time duration (60–180 min) and temperature (25–45° C). Water swelling capacity, metal ion sorption and flocculation studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. 相似文献