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1.
Capsule Blue Tits sang their dawn song in trees that provided greater concealment.

Aims To determine if dawn singing Blue Tits select trees that increase their concealment.

Methods We compared the timing of leaf growth initiation in Blue Tit song-post trees to the average timing of leaf growth initiation for other tree species within 25 m of the song-post.

Results Most Blue Tits (96%, n = 23) sang from tree species that begin leaf growth earlier than the average tree available within 25 m. If males singing in Hawthorns Crataegus monogyna were excluded, 92% (n = 13) sang from earlier leafing trees.

Conclusion Dawn singing Blue Tits select perches that offer greater concealment.  相似文献   

2.
A list of 285 species of Sarcophagidaе in the Middle East countries is presented with distributional data, including Bahrain (3 species), Cyprus (46), Egypt (both African and Asian parts) (114), Iran (83), Iraq (17), Israel (113), Jordan (14), Kuwait (3), Lebanon (13), Oman (2), Gaza Strip (5), Palestinian Authority (42), Quatar (1), Saudi Arabia (37), Syria (42), Turkey (both European and Asian parts) (157), United Arab Emirates (14) and Yemen (15). Three new synonyms are established: Blaesoxipha delilah Lehrer, 2006 = Agriella setosa Salem, 1938, syn. n.; Blaesoxipha nahaliana Lehrer, 2008 = Blaesoxipha popovi Rohdendorf, 1937, syn. n.; and Liosarcophaga daccanella Lehrer, 2008 = Liosarcophaga (s. str.) dux (Thomson, 1869), syn. n. Four new combinations for species names are proposed: Liopygia (Engelisca) adhamae (Lehrer & Abou-Ziad, 2008), comb. n.; Liosarcophaga (s. str.) pedestris (Villeneuve, 1910), comb. n.; Liosarcophaga (Pandelleisca) theodori (Lehrer, 1998), comb. n., and Liosarcophaga (Pharaonops) tewfiki (Salem, 1940), comb. n.  相似文献   

3.
《Journal of bryology》2013,35(3):365-382
Abstract

The chromosomes of one moss and thirty liverworts are described and discussed taxonomically. Those of Lepidozia pearsonii (n = 8 + 1m), Telaranea murphyae (n = 9), Leioeolea badensis (n = 8 + 1m), Pleetoeolea paroiea (n = 9), Nardia compressa (n = 8 + 1m), N. geoscyphus (n = 9), Lophoeolea bispinosa (n = 8 + 1m), L. semiteres (n = 8 + 1m), Saccogyna viticulosa (n = 8 + 1m), Scapania curta (n = 16 + 2m), S. compacta (n = 8 + 1m), Porella laevigata (n = 8 + 1m) and P. cordaeana (n = 8 + 1m) are believed not to have been reported previously and, despite references in the literature to the cytology of Riccia crystallina and Gymnocolea inflata, reasons are given for suggesting that the present counts of n = 7 + 1m and n = 8 + 1m, respectively, may also be the first. The remaining species have been recorded cytologically in other parts of the world but not previously for Great Britain, or not with the present karyotype.  相似文献   

4.
Five fluorescent symmetrical dimeric bisbenzimidazoles DB(n) containing four 2,6-substituted benzimidazole cores and differing in the length of the oligomethylene linker between two bisbenzimidazole rings (n = 3, 4, 5, 7, 11) have been synthesized. The ability of the dimeric bisbenzimidazoles to form complexes with the double-stranded DNA has been shown by spectral methods. Upon binding to the double-stranded DNA, DB(n) are localized in the narrow groove. The data on the inhibition of the DNA methyltransferase Dnmt3a by DB(n) indicate that dimeric bisbenzimidazoles DB(3) and DB(11) site-specifically bind to the oligonucleotide duplex.  相似文献   

5.
《Journal of bryology》2013,35(2):259-263
Abstract

Chromosome counts are reported from five species of Antarctic hepatics belonging to five genera and four families. The chromosome numbers in the genera Herzogobryum (H. teres n = 9) and Paehyglossa (P. dissitifolia n = 9) are reported for the first time. The first chromosome count from Lophozia excisa, n = 27, is the highest reported from Lophozia. A diploid number, n = 18, is reported for the first time from Barbilophozia hateheri; a second count, n = 9, agrees with earlier reports. The commonest Antarctic liverwort Cephaloziella cf. exili[lora has n = 18 and this agrees with earlier reports for the genus.  相似文献   

6.
Δ13C were determined for herbarium specimens of 12 C3 plants (trees, shrubs and herbs) collected during the last 240 years in Catalonia, an area with a Mediterranean climate. Values were 19.91 (S.E. = 0.32, n= 21) for 1750–1760, 19–86 (S.E. = 0.21, n= 49) for 1850–1890 and 19.95 (S.E. = 0.29, n= 25) for 1925–1950, and decreased significantly to 18.87 (S.E. = 0.31, n= 29) for 1982–1988. More irregular temporal changes were found in Δ13C of two C4 species, but they also suggest a decrease in discrimination in recent decades. These results suggest that either carbon assimilation rates have increased or stomatal conductance has decreased, and therefore, that there has been an increase in water use efficiency over the last few decades.  相似文献   

7.
Reaction of o-mercaptopyridine (o-MPH) and trithiocyanuric acid (TTCyH3) with one equivalent of BunLi in the presence of HMPA yields the mono-lithiated salts MPLi.HMPA (1) and TTCyH2Li.2HMPA (2) respectively, which have been characterised by NMR spectroscopy and X-ray crystallography. Reaction of three equivalents of BunLi with anhydrous TTCyH3 in THF yields the tri-lithiated species TTCyLi3.4THF (3). In all three compounds the lithium centres have N,S-bridged coordination modes. Whereas 1 is dimeric in the solid state, 2 has an unusual monomeric structure and 3, which is a very rare example of a structurally characterised tri-lithiated compound, has an unprecedented polymeric structure incorporating (NCSLi) n (n = 1, 2) rings. The structural diversities displayed by 1 and 2 have been probed, and thereby in part rationalised, by ab initio (6-31G*/RHF, 6-31G**/RHF and 6-31G*/MP2 levels) MO calculations on both their thio-keto and thiol isomers and on their uncomplexed and complexed lithiated derivatives. In particular, the optimised structures predict and reproduce the N,S-bridging coordination modes found for lithium and explain why structure 1 is dimeric whereas 2 is monomeric.Electronic Supplementary Material available.  相似文献   

8.
The infrared absorption properties of monodispersed, chemically and optically pure ‘amino-PEG’-bound linear homooligopeptides having the general formula t-Bx(l-Met)n NHPEG, n = 1–15 and H2+(l-Met)nNHPEG, n = 1–14 have been investigated in the solid state. The critical sizes for development of the β-structure and α-helix (n = 3 and n = 13, respectively), and the effect, on the latter, of the solvent from which the solid samples are cast, have been established.  相似文献   

9.
The fauna of the genus Sphaerophoria Le Peletier et Serville, 1828 of Siberia and adjacent territories is analyzed on the basis of examination of the material deposited at the Siberian Zoological Museum, Institute of Systematics and Ecology of Animals, Russian Academy of Sciences, Siberian Branch (Novosibirsk), and at the Zoological Institute, RAS (St. Petersburg). The following new synonymies are established: Sphaerophoria interrupta (Fabricius, 1805) = Sph. altaica Violovitsh, 1976, syn. n.; Sphaerophoria macrogaster (Thomson, 1869) = Sph. krocha Violovitsh, 1976, syn. n.; Sphaerophoria rueppellii (Wiedemann, 1830) = Sph. montivaga Violovitsh, 1985, syn. n.; Sphaerophoria macrogaster (Thomson, 1869) = Sph. nana Violovitsh, 1976, syn. n.; Sphaerophoria chongjini Bańkowska, 1964 = Sph. tinae Violovitsh, 1976, syn. n. Sphaerophoria kamtshatica Violovitsh and Sph. sachalinica Violovitsh are regarded as nomina nuda. Sphaerophoria bankowskae Goeldlin, 1989; Sph. laurae Goeldlin, 1989; Sph. potentillae Clausssen, 1984 and Sph. turkmenica Bańkowska, 1964 are found in Russia for the first time. A number of species is also reported for different territories of Siberia for the first time.  相似文献   

10.
The spectral sensitivity of 21 eye preparations of Ascalaphus (Libelluloides) macaronius (Insecta, Neuroptera) has been re-measured using an up-to-date spectral scan method. 1. Dorso-frontal and ventro-lateral eyes have different spectral characteristics with peaks of sensitivity at 329 ± 8 nm (n = 15) and 343 ± 4 nm (n = 5) (P = 0.002), respectively. 2. The absorbance of the visual pigment layer, K, determined from the shape of the spectral sensitivity curves is 1.3 ± 1.8(n = 15) for dorso-frontal eyes and – 1.0 ± 0.3(n = 5) for ventrolateral eyes, thus implying higher selfscreening in the dorso-frontal eyes and narrowing of the spectral sensitivity curves as regards to a template visual pigment in ventro-lateral eyes. 3. Plotting K versus spectral sensitivity peak wavelength max revealed an inverse correlation between these variables with K = 42.5 – 0.126 max at r = 0.88(n = 19). 4. Extracts of ommochromes and carotenoids (Figs. 4 to 6) do not allow to account for the above diversity of optical properties of the Ascalaphus eye (Fig. 7).Abbreviations SSC spectral sensitivity curve - DF dorso-frontal eye - UV ultraviolet - VL ventro-lateral eye  相似文献   

11.
《Journal of bryology》2013,35(3):487-490
Abstract

Cytological observations are made on seven species belonging to seven families. The genera Solmslella (S. ceylonica, n= 11+m) and Pterobryopsis (P. orientalis, n=7) and the species Macromitrium himalayanum (n = 11), Chrysocladium phaeum (n=10) and Homaliodendron obtusatum (n=10+m) are reported on for the first time. One bivalent in the complements of Macromitrium himalayanum, Leucodon secundus and Trachypodopsis serrulata was found to be heteromorphic.  相似文献   

12.
Chromosome numbers are presented for 28 species of the genus Perityle, one putative inter-sectional hybrid, two species of Amauria, one species of Eutetras, and one species of Pericome. For Perityle, initial counts are recorded for 12 species of sect. Laphamia (n = 16, 17, 18, 36, ca. 102) and 11 species of sect. Perityle (n = 11, 12, 13, 16, 17, 18, 19, 34, 51). Chromosome numbers for the two species of Amauria (n = 18) are first reports for the genus. Including the current information, chromosome numbers have been recorded for 37 of the approximately 50 species recognized for Perityle. At least 24 taxa have numbers of n = 17, suggesting a base chromosome number of x = 17 for Perityle.  相似文献   

13.
Abstract

Objective: Few studies have investigated haem oxygenase-1 gene (HMOX1) promoter polymorphism in microvascular angina (MVA).

Materials and methods: HMOX1 promoter (GT)n repeats were examined in healthy controls (N?=?220) and MVA subjects (N?=?181).

Results: The distribution of genotype of SS, SL and LL were significantly different in MVA (17%, 51%, 33%) vs. normal controls (35%, 46%, 20%) (p?<?0.001, S allele: ≤30 repeats, L allele: >30 repeats). In multivariate analysis, carrier of L allele (odds ratio 2.772, p?<?0.001) was a significant predictor for the diagnosis of MVA.

Conclusions: Subjects with MVA had longer HMOX1 promoter (GT)n repeats than the healthy controls.

Trial registration number: NCT01198730 at https://clinicaltrials.gov  相似文献   

14.
Chromosome counts are reported for 71 collections in 14 taxa of Lipochaeta DC. (Compositae) of the Hawaiian Islands. Counts for 13 of the taxa are first reports. Lipochaeta contains diploids, n = 15, and tetraploids, n = 26. Ploidy level is taxonomically significant for recognizing sections, and on the basis of these data, together with morphological and chemical evidence, major realignments of species into the secions of Lipochaeta have been made.  相似文献   

15.
Abstract

This paper concentrates on two very important conducting polymers poly(p-phenylene) and polypyrrole. Detailed atomistic molecular models have been developed with the help of ab initio and semi-empirical quantum mechanical calculations using the Cerius2 and WinMOPAC (version 6.0) programs.

Their optimised geometry had been calculated and compared with experimental X-ray diffraction data. The simulated and experimental vibrational spectra of biphenyl as well as isolated pyrrole monomers and oligomers from n = 1 and 2, where n is the number of structural repeat units used, have been computed using the ab initio 3–21G basis set. The results obtained are compared with experimental data for the case of biphenyl and for oligomers with n = 2 to 5 for both neutral benzenoid and quinonoid oligopyrroles, from semi-empirical predictions obtained by AM1 and PM3. The trends in the computed harmonic force fields, vibrational frequencies and intensities are monitored as a function of the chain length. The data are analyzed in conjunction with the trends in computed equilibrium geometries.  相似文献   

16.
Restriction fragment length polymorphism haplotyping of mutated and normal phenylalanine hydroxylase (PAH) alleles in 49 Dutch phenylketonuria (PKU) families was performed. All mutant PAH chromosomes identified by haplotyping (n = 98) were screened for eight of the most predominant mutations. Compound heterozygosity was proven in 40 kindreds. Homozygosity was found for the IVS12nt1 mutation in 5 families, and for the R158Q and IVS10nt546 mutations in one family each. All patients from these families suffer from severe PKU, providing additional proof that these mutations are deleterious for the PAH gene. Genotypical heterogeneity was evident for mutant haplotype 1 (n = 27) carrying the mutations R261Q (n = 12), E280K (n = 4), P281L (n = 1) and unknown (n = 10), and likewise for mutant haplotype 4 (n = 30) carrying the mutations R158Q (n = 13), Y414C (n = 1) and unknown (n = 16). Mutant haplotype 3 (n = 20), in tight association with mutation IVS12nt1, appeared to be in strong linkage disequilibrium (LDE) with its normal counterpart allele (n = 4). Mutant haplotype 6 (n = 4), in tight association with the IVS10nt546 mutation, showed moderate LDE with its counterpart allele (n = I). The distribution of the mutant PAH haplotypes 1, 3 and 4 among the Dutch PKU population resembles that in other Northern and Western European countries, but it is striking that mutant haplotype 2 and its associated mutation R408W is nearly absent in The Netherlands, in strong contrast to its neighbouring countries.  相似文献   

17.
《Journal of bryology》2013,35(4):532-536
Abstract

The chromosome numbers of five species belonging to the Jubulae have been described, and are as follows:

Lejeuneaceae

Cololejeunea cf. dissita, n = 9.

Arehilejeunea autoiea Vanden Berghen, n=9.

Caudalejeunea hanningtonii (Mitt.) Schiffn., n =9.

Mastigolejeunea florea (Mitt.) Steph., n=9.

Frullaniaceae

Frullania spongiosa Steph., female, n = 9.

F. spongiosa Steph., male, n=8.

The author wishes to thank Dr E. W. Jones for assistance in identifications, especially with Cololejeunea cf. dissita.  相似文献   

18.
Optimising multi-tier open nucleus breeding schemes   总被引:2,自引:0,他引:2  
Summary The constant migration (CM) method and the ebv migration (EBVM) method of optimising the design of multi-tier open nucleus breeding schemes are presented and compared. The equation for the equilibrium rate of genetic gain of a three-tier open nucleus scheme is determined using the CM method. The major advantage of the EBVM method is the reduction in the number of parameters which have to be varied in order to locate the maximum equilibrium rate of genetic gain. For the CM method for the number of variable parameters is 5, 14, 27 and (2n + 1) (n - 1) for unrestricted male and female migration in schemes with 2, 3, 4 and n tiers respectively. The corresponding number of variable parameters for the EBVM method is 1, 2, 3 and n-1 respectively. A procedure is given for the EBVM method so as to accomodate variance loss due to selection and variance gain due to the mixing of groups with a different mean breeding value.  相似文献   

19.
Abstract

Cytotaxonomical studies in Artemisia vulgaris L. and Artemisia verlotorum Lamotte. — Karyotype analysis of A. vulgaris and A. verlotorum has shown in the first species, in agreement with previous data, a chromosome number of 2n=16 and in the second the chromosome number of 2n=48 which does not agree with previous data. This seems to be the first case of polyploidy observed in Artemisia with basic number eight. A few specimens of A. verlotorum had shown 2n=48 + 2B chromosomes. The comparison of karyotypes has shown that, while the two species have, in some respect, the same degree of symmetry (ΣL%=57; ΣC9% = 43), the quality of their chromosomes is different (see karyotype formulas). We see no explanation for such an unlikely phenomenon.  相似文献   

20.
Abstract

Starting from 2′,3′,5′-tri-O-acetyl-2-iodoadenosine, 9-(β-D-arabinofuranosyl)-2-(p-n-butylanilino)adenine and its 2′(S)-azido counterparts were synthesized in seven steps. These exhibited only moderate growth-inhibitory effects against mouse leukemic P388 cells (IC50 = 13–24 μM), although 5′-triphosphate derivatives showed strong and selective inhibitory action on calf thymus DNA polymerase α, but not on β- and ?-polymerases from eukaryotes.

  相似文献   

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