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1.
《Ibis》1930,72(S1):458-461
A part from considerations as to where it is best wedged into the linear sequence, the brachyptera group is defined in general terms as a compact group of four small or very small species which resemble one another in many important specific characters and the other thirty-six species classified here as Cisticola in so many ways of form, coloration and behaviour as to make them best understood by classifying them also under that generic name.  相似文献   

2.
《Ibis》1930,72(S1):408-410
The B. O. C. Ruwenzori expedition of 1906 brought home a single immature female of this species, obtained in a papyrus swamp near Lake George, and to Ogilvie-Grant's discrimination we owe the recognition of its specific distinction from galactotes , the species it so closely resembles in coloration, and which is certainly carruthersi s nearest ally.  相似文献   

3.
《Ibis》1930,72(S1):156-172
This third species of Cloud-scraper was first named by Dr. von Heuglin in 1862 from an adult male in Summer dress obtained by himself in Abyssinia. Later (in 1869), not realizing their specific identity, von Heuglin gave examples of the same species in Winter and juvenile dresses with different specific names, viz. iodopyga and habessinica , but did not have to contend with the difficulty of separating ayresii from brunnescens because the former species does not occur in Abyssinia. Elsewhere, from Kenya Colony to South Africa, that has always been the difficulty, and wherever the two species were subsequently found they were more or less indiscriminately related to one another as forms or allies of ayresii (under that bird's wrong name terrestris) , until, in 1913 *, Roberts showed the differences between them in South Africa, and, in 1922†, van Someren the same for Kenya Colony.  相似文献   

4.
《Ibis》1930,72(S1):461-493
What has been said about it in the introduction to the group leaves little necessary to say here of brachyptera s systematic position, but the following historical note relating to the bird's confusion with rufa will probably be useful.  相似文献   

5.
The curricula vitae of four candidates for a professorial appointment at Athens University were examined to estimate the actual contribution of each candidate to the papers of which he was a coauthor. A total of 879 research papers by the four candidates were analysed in terms of the number of authors, the sequence of names, and the year of publication. The four authors presented 364, 349, 96, and 70 papers. If an equal contribution of all coauthors is assumed, the actual number of papers (all papers divided by the number of authors), is about 106, 83, 28, and 26, respectively, so that the rank of the four candidates did not change. On the assumption that the contribution was related to the candidate''s position in the order of the coauthors'' names, the numbers of papers were corrected to 84, 95, 26, 33 using one statistical method and to 88, 94, 28, 31 using another. These assumptions may not be valid, however, especially as the last author may be more important than the intermediate ones. It is suggested that the journals require authors to state their specific contribution to a paper, such as original idea, planning, collecting data, writing up, etc.  相似文献   

6.
Recently the word P.A.D.A.M. has been proposed to replace the term Andropause (Partiel Andrologen Deficiency in Aging Males). This implies that most if not all problems of the aging male are due to testosterone déficiency, which is not at all true when one considers the results of endocrine investigations in that group. So many other sociological and relational causes are involved that the term P.A.D.A.M. is clearly a misnomer.  相似文献   

7.
Abstract

On 23 February 1979 Sir Robert Falla collapsed and died at his home in Eastbourne. He was 77. His sudden death came as a great shock to his multitude of friends and colleagues, many of whom were still sharing with Sir Robert a deep sense of loss at the death on 31 May 1978, shortly after the couple's golden wedding anniversary, of his charming wife Molly.  相似文献   

8.
《Ibis》1930,72(S1):413-432
With what has already been said of the bird in the Definition of the pair and the Key to species, robusta requires little farther introduction. Some peculiarities in the bird's moults will require particular attention later on, when it comes to defining the racial variation.  相似文献   

9.
C Reyns  J Léonis 《Biochimie》1975,57(2):131-138
The catalysis of the hydration of fumarate and deshydration of L - malate by chicken fumarase was measured spectrophotometrically over a range of substrate concentrations from 4 times 10(-3) M to 8 times 10(-5) M for fumarate and from 8 times 10(-2) M to 10(-3) M for L - malate. For the forward and reverse reactions, linear Lineweaver and Burk plots were obtained. The Michaelis constants and the maximum initial velocities for both substrates were determined and the Haldane relation was found to be obeyed. The effect of pH on activity was investigated over a pH range from 5.5 to 9.0 and the data indicate the presence, in the active site, of two ionizable groups, one in the acidic form and one in the basic form. The values of the ionization constants, determined for the enzyme - substrate complexes, agree closely with the ones obtained for the porcine enzyme. The mode of action of twenty-four structural analogs on the initial velocity of the dehydration of L-malate, by chicken fumarase was examined. From these studies, two regions positively charged appear necessary for the effective binding of the carboxylates of the substrates and competitive inhibitors to the active center. Moreover, the data suggest the presence of an additional group, in the catalytic site of chicken fumarase, that stabilizes the carbon-carbon double bond common to fumarate and its structural analogs. Finally, from the comparison of the kinetic properties of the chicken and pig fumarases, it may be concluded that the catalytic mechanism of the homologous enzymes are very similar, if not identical.  相似文献   

10.
Thirty-four patients having among them cardiac valve deformities of five different types were operated upon with the heart opened to expose the surgical field to direct vision.Five of them died, including three of the first six. Of 29 surviving patients, 26 were greatly improved and leading a normal life. The other three were slightly to moderately improved.  相似文献   

11.
《Ibis》1930,72(S1):77-111
The only European and most familiar species * of the whole genus Cisticola , of which, according to ancient designation †, it is the representative type-species. It is also the species with the widest range.  相似文献   

12.
Encephalitis is a challenging public health problem in Kern County and in the San Joaquin Valley area. During the last ten years the authors have studied the epidemiology of encephalitides due to arthropod-borne viruses and the methods used in the differential dignosis of these conditions. To incriminate a virus it is necessary to demonstrate a rise in antibody titer in the blood over a period of seven to fourteen days, the first specimen to be taken as soon as possible after onset of symptoms. A variety of tests may be necessary in some cases. Among the patients included in this presentation the greater number of those with encephalitis and also of those with poliomyelitis were under 30 years of age. The age range was five weeks to 49 years. The median annual mortality rate was 4.3 deaths per 100 cases for poliomyelitis and 3.9 for encephalitis. The greatest incidence occurred during the summer months.The clinical manifestations usually observed in encephalitis are described, but it is emphasized that wide variations and even completely atypical clinical phenomena are encountered. Four representative cases are reported and treatment is discussed. Vaccination and vector control are considered as the most promising means of combating the disease.  相似文献   

13.
《Ibis》1930,72(S1):180-206
The only species of Cisticola not inhabiting Africa at all, but with headquarters in south-eastern Asia and Australia, and ranging thence no further to the westward than southern India: Latham's English name, "The Exile Warbler"*is therefore very appropriate.  相似文献   

14.
15.
《Journal of bryology》2013,35(3):449-450
Abstract

A single, small moss leaf has been found among very small amounts of contents extracted from the Tyrolean Iceman's colon. It belongs to the species Neckera complanata Hedw., a woodland moss of low to moderate altitudes. The leaf was accidently ingested and not consumed as food.  相似文献   

16.
A previously undescribed species of Euglena, E. myxocylindracea, sp. nov., is described from soil in a garden and in a while pine woods in Pike County, Pa. In addition to the, type, an organism (No. 457) in the Culture Collection of Algae. Indiana University, hitherto designated E. viridis var. terricola. is transferred to E. myxocylindracea as var. terricola. Differences such as the usual absence of an emergent flagellum, or the presence of an extremely short one (ca. 3.5–4 μ), and the dominance of a palmelloid state in a variety of liquid and solid culture media in which the cells secrete dichotomously branching slimy cylinders distinguish the new species from E. viridis.  相似文献   

17.
《Ibis》1930,72(S1):244-275
First named in 1843 from a single specimen obtained by Dr. Andrew Smith's expedition. near the southern limit of its range, the South African bird, as one of the medium sized, pattern-backed Cisticolae may be said to have finally come into clear definition in Roberts' 1913 Review after a long period of endless confusion with some or all of the species of the subruficapilla group. But that does not entirely clear the ground for chiniana , for it is a remarkably plastic form in so far as coloration goes, and north of the Zambesi, particularly in equatorial East Africa, presents certain geographical variations of coloration which have tended towards confusing it with some of the plain-backed species of the genus.  相似文献   

18.
Werger  Marinus J. 《Plant Ecology》1998,134(2):243-248
We determined the role of bird dispersal in seed and seedling dynamics of the tree Kalopanax pictus from 7 years of observing seed rain and seedling emergence in a broad-leaved deciduous forest in central Japan. We also performed an experiment on the influence of seed pulp on germination of seeds of K. pictus. Seeds of this species can lie dormant for several years, and this causes rather constant yearly seedling emergence in spite of irregular seed production. The spatial distribution of the seedlings that emerged each year (maximum distance from nearest conspecific seed-bearing tree of 90 m) was wider than that of gravity-dispersed seeds (max. distance of 37 m), suggesting seed dispersal by birds in winter. Emerged seedling densities at sites over 20 m from the nearest conspecific seed-bearing tree were highest in the spring of 1991, about half a year after the largest seed fall of the observation period. However, emerged seedling densities within 20 m from seed-bearing trees were highest in 1992, 1.5 years after the largest seed fall. These field observations may be explained by the experimental results on the effects of seed pulp on germination. Intact seeds germinate slowly at low germination rates, while seeds without seed pulp germinate quickly at high germination rates. Fallen seeds with seed pulp thus appear to form a seed bank near seed sources (temporal dispersal), while seeds scattered by birds appear to increase the possibility of reaching the present safe sites in distant areas with quick germination (spatial dispersal).  相似文献   

19.
E.p.r. signals were detected in an all-trans-retinoic acid/haematin incubation mixture by using an e.p.r. spin-trapping technique. The spin adducts are presumably attributable to some intermediates in haematin-catalysed retinoic acid 5,6-epoxidation, since addition of nitrosobenzene to the reaction mixture dose-dependently inhibited the epoxidation. Analysing the reaction mixture by h.p.l.c.-e.p.r. spectrometry resulted in the detection of three peaks (III-1, III-2, IV) ascribable to the radical species. Two (peaks III-1 and -2) of the three peaks, which appeared 10 min after the reaction had started, seem to be attributable to the radical species directly participating in the epoxidation. The radicals trapped by nitrosobenzene do not appear to be derived from active oxygen, since none of these peaks were detected in a similar h.p.l.c. analysis of O2- and OH.-generating systems. They are presumably derived from retinoic acid. This view is also supported by the following results: none of these peaks were detected in the h.p.l.c. elution profile of the reaction mixture when retinoic acid was absent; peaks III-1 and 2 were detected even under anaerobic conditions, and their peak heights were unchanged under aerobic conditions.  相似文献   

20.
Electron-spin-resonance measurements have been made on single crystals of uracil-beta-D-arabinofuranoside, which were irradiated by 4-0 MeV electrons at 77 K. At low temperatures, two radicals have been identified, one attributed to a hydrogen abstraction from 05' in the sugar moiety and the other to a radical anion located on the pyrimidine ring. The former is very unstable and seems to act as a precursor to other unidentified radical species stable at 77K. At room temperature, the main resonance is due to hydrogen addition to C5 and is probably produced by protonation of the anion. This same radical is also produced by X-irradiation at room temperature.  相似文献   

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