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1.
Prof. Elio Baldacci 《Mycopathologia》1939,2(2):145-161
Riassunto Lo studio comprende una revisione critico-sperimentale della specie Actinomyces albus, della quale vengono considerati come sinonimi circa 30 nomi speeifici, fra i quale A. chromogenus, A. odorifer, A. thermophylus p.p.; della specie é data una diagnosi ed una particolareggiata descrizione.Sono inoltre studiate le specie A. viridis, (= A. viridochromogenus) e A. innominatus, n. nomen. Quest'ultima é preceduta da una breve discussione sulla specie A. homini.
Summary Twenty-six strains of Actinomyces albus are studied redescribed from morphological, cultural and biochemical standpoints. Many biological activities of A. chromogenus, A. odorifer and A. thermophilus are in common with other species of the same genus, so that they may be considered for sub-specific, (not specific) differentiation. A discussion on A. farcinicus, A. albidoflavus and A. aureus has been originated from mislabeling as A. albus; the group including the two last named species (flavus group) must be revised. A few strains classified A. farcinicus are in no doubt true A. albus, but this real specific entity remains to be revised from Nocard's strain. A. viridis, for the first time described by Lombardo-Pellegrino, has been redescribed three times as a new species under the same binomial, and the fourth as A. viridochromogenes. A. hominis Bostroem is an uncorrect determination for the species originally described by Waksmann and Curtiss, and it is renamed A. innominatus, the binomial A. (Streptothrix) hominis Auct. being a nomen ambiguum. In conclusion, 30 bionmial are appended in sinonimy to A. albus, including Cladothrix dichotoma Macé (1888) non Cohn, G. invulnerabilis Acosta et G. Rossi, C. odorifera Rullm. Actinomyces chromogenus Gasp., A. thermophilus Auct., p.p., A. (Streptothrix) Sanninii (Cif.) Westerd., A. Almquisti Duché, A. Gougeroti Duché, and so on.相似文献
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Walker Lake, a large terminal lake in west-central Nevada, is rapidly desiccating and becoming more saline. From 1937 to 1977, total dissolved solids increased from 5 650 to 10 650 mg l–1. Ionically, the lake is a chlorocarbonate one; however, as desiccation continues it should eventually have about equal amounts of chloride, sulfate and carbonate. With regard to algal nutrients, the lake appears to be nitrogen limited. The phytoplankton is currently dominated by Nodularia spumigena; at times this produces noxious blooms. The zooplankton community is depauperate and composed of three species. The fish fauna is limited to three endemic fishes, with tui chub, Gila bicolor, dominant. Lahontan cutthroat trout, Salmo clarki henshawi, is restricted during summer to a narrow mid-water zone low enough in temperature and high enough in dissolved oxygen to meet physiological requirements.Dr. Koch passed away in October 1983. 相似文献
4.
IAWA (International Asso ciation of Wood Anato mists) publishesa high quality journal in four parts, comprising about 500 pagesa year. Every so often they publish supplements that are muchlonger and more comprehensive than traditional scientific papers.The first two were Bibliography of systematic wood anatomy ofdicotyledons (265 pages) by Mary Gregory (1994) and Wood anatomyof Sapindaceae (214 pages) by René Klaasen (1999). Thisthird supplement is on a fossil flora which has many well-preservedwoods that have now been studied in detail. The only minor criticismI have is that the title of 相似文献
5.
Haplodontium zangii X.R.Wang &; J.C.Zhao, a new moss species from Xizang, China, is described and illustrated. Previously, specimens of H. zangii have been identified as Mielichhoferia himalayana Mitt. However, H. zangii is distinctly different from M. himalayana in having excurrent costae with short awns (vs long denticulate awns), short-pyriform capsules, 0.8–1?mm (vs long-pyriform capsules, 2.5–3?mm), and densely papillose exostome teeth (vs smooth or vertically striped exostome teeth). Haplodontium zangii is similar to H. macrocarpum (Hook.) J.R.Spence, which was traditionally placed in Mielichhoferia Nees &; Hornsch. as M. macrocarpa (Hook.) Bruch &; Schimp. The main differences between H. zangii and H. macrocarpum are in the morphology of the leaves, capsules, guide cells, and stomata. Mielichhoferia himalayana and another Chinese species of Mielichhoferia, M. sinensis Dix., are also transferred to Haplodontium Hampe, a new genus in the bryoflora of China, as H. himalayanum (Mitt.) X.R.Wang &; J.C.Zhao and H. sinensis (Dix.) X.R.Wang &; J.C.Zhao. A morphological comparison and a key to the three species of Haplodontium in China as well as to H. macrocarpum, a species that is likely to be found in China, are provided. 相似文献
6.
Stanley W. Watson Linda B. Graham Charles C. Remsen Frederica W. Valois 《Archives of microbiology》1971,76(3):183-203
Summary
Nitrosolobus multiformis is a lobular shaped, previously undescribed ammonia-oxidizing bacterium. The organism is ubiquitous and was isolated from soil samples obtained in various parts of the world. Its lobular nature and its internal, partially compartmentalized cytoplasm makes it morphologically unique and easily distinguishable from all other microorganisms. Physiological compartmentalization also occurs and is characterized by glycogen deposition in the peripheral compartments of the cell. The cells are obligate chemoautotrophs using CO2 and ammonia as primary carbon and energy sources. Its obligate chemoautotrophic nature stems primarily from a metabolic deficiency. Even though the cells cannot be grown on an organic medium the cells still have a slight heterotrophic potential and are able to oxidize and assimilate minute amounts of acetate in the absence of an inorganic energy source.Contribution No. 2606 from the Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543. 相似文献
7.
John C. Semple 《American journal of botany》1984,71(4):522-531
Chromosome number determinations from 118 populations of eight species of the aster genus Virgulus are reported for the first time. Based on these counts and literature reports the geographic distributions of diploids and tetraploids in V. concolor, V. novae-angliae, V. oblongifolius, and V. patens have been determined. In the first three species, diploids were widely distributed, while tetraploids were more restricted. In V. patens, diploids were restricted to the southwestern portion of the species’ range, while tetraploids were found throughout the range. Both V. adnatus and V. walteri were found only at the tetraploid level throughout their ranges. Two other species with restricted distributions were consistently found to be high level polyploids: V. georgianus with 2n = 50, V. grandiflorus with 2n = 60. The following new combinations are listed: Virgulus georgianus (Alexander ex Small) Semple; Virgulus subsect. Brachyphylli (Torr. & Gray) Semple; and Virgulus sect. Polyliguli (Semple & Brouillet) Semple. 相似文献
8.
Some physical, catalytic, and regulatory properties of ketopantoate hydroxymethyltransferase (5,10-methylenetetrahydrofolate: alpha-ketoisovalerate hydroxymethyltranferase) from Escherichia coli are described. This enzyme catalyzes the reversible synthesis of ketopantoate (Reaction 1), an essential precursor of pantothenic acid. (1) HC(CH3)2COCOO- + 5,10-methylene tetrahydrofolate f in equilibrium r HOCH2C(CH3)2COCOO- + tetrahydrofolate It has a molecular weight by sedimentation equilibrium of 255,000, a sedimentation coefficient (S20,w) of 11 S, a partial specific volume of 0.74 ml/g, an isoelectric point of 4.4, and an absorbance, (see article), of 0.85. Polyacrylamide gel electrophoresis in sodium dodecyl sulfate and amino acid analyses give a subunit molecular weight of 27,000 and 25,700, respectively; both procedures indicate the presence of 10 identical subunits. The NH2-terminal sequence is Met-Tyr---. The enzyme is stable and active over a broad pH range, with an optimum from 7.0 to 7.6. It requires Mg2+ for activity; Mn2+, Co2+, Zn2+ are progressively less active. The enzyme is not inactivated by borohydride reduction in the presence of excess substrates, i.e. it is a Class II aldolase. Reaction 1f is partially inhibited by concentrations of formaldehyde (0.8 mM) and tetrahydrofolate (0.38 mM) below or near the Km values, apparent Km values are 0.18, 1.1 and 5.9 mM for tetrahydrofolate, alpha-ketoisovalerate, and formaldehyde, respectively. For Reaction 1r, apparent Km values are 0.16 and 0.18 mM, respectively, for ketopantoate and tetrahydrofolate, and the saturation curves for both substrates show positive cooperativity. Forward and reverse reactions occur at similar maximum velocities (Vmax approximately equal to 8 mumol of ketopantoate formed or decomposed per min per mg of enzyme at 37 degrees). Only 1-tetrahydrofolate is active in Reaction 1; d-tetrahydrofolate, folate, and methotrexate were neither active nor inhibitory. However, 1-tetrahydrofolate was effectively replaced with conjugates containing 1 to 6 additional glutamate residues; of these, tetrahydropterolpenta-, tetra-, and triglutamate were effective at lower concentrations than tetrahydrofolate itself; they were also the predominant conjugates of tetrahydrofolate present in E. coli. Alpha-Ketobutyrate, alpha-ketovalerate, and alpha-keto-beta-methylvalerate replaced alpha-ketoisovalerate as substrates; pyruvate was inactive as a substrate, but like isovalerate, 3-methyl-2-butanone and D- or L-valine, inhibited Reaction 1. the transferase has regulatory properties expected of an enzyme catalyzing the first committed step in a biosynthetic pathway. Pantoate (greater than or equal to 500 muM) and coenzyme A (above 1 mM) all inhibit; the Vmax is decreased, Km is increased, and the cooperativity for substrate (ketopantoate) is enhanced. Catalytic activity of the transferase is thus regulated by the products of the reaction path of which it is one component; transferase synthesis is not repressed by growth in the presence of pantothenate. 相似文献
9.
Andra Scozzafava 《Inorganica chimica acta》1984,92(1):89-96
A comprehensive mechanism is proposed for the photolysis of transition metal complexes in equilibrium solutions. This involves the photo-oxidation, a possibility of energy transfer and several secondary thermal reactions, e.g. forward and back reactions with photochemically-formed H· radicals. The scheme includes the individual quantum yield (IQY) of each species. The photo-oxidations of FeSO4, FeClO4, FeCl2 in aqueous acidic solutions were studied by continuous irradiation. The IQY of Feaq2+ (0.2), FeSo4 (0.3), FeHSO4+ (0.67), FeClO4+ (0.06–0.2), FeCl+ (0.8), FeCl2 (0.3) were determined. The IQY was found to be dependent on H+ concentration, due to competition with geminal recombination within the solvent cage. This dependence, and the efficiency of energy transfer between excited iron(III) species and iron(II) in ground state, are discussed. 相似文献
10.
Concern about colonization of marshesby plant species such as Phragmites australisand Lythrum salicariahas highlighted the needfor management strategies. However, there is a lack ofinformation in the literature on which to base thesedecisions. This study compares the alpha diversity ofmarshes to assess the impact of invasion by Phragmitesand Lythrum. Species occurrence andstem density were measured in marshes dominated by Phragmites, Lythrum, Typhaspp., or otherherbaceous perennials in the Charles River watershedin eastern Massachusetts, USA, and species richness,Shannon's H, Simpson's reciprocal (1/D), and Pielou'sJ were compared among six community types. The threediversity indices had significantly higher values forTypha-Lythrummarshes than for any of the othermarsh types (Tukey test, p< 0.05), with mean values(± s.d.) of H = 2.00 ± 0.74, 1/D = 3.51± 1.68 and J = 0.69 ± 0.1. Marshes dominatedby Phragmiteshad the lowest diversity, with H= 0 and D = 1, i.e. they were monospecific. Typhadominated marshes had the second lowest values,with H = 0.17 ± 0.05, 1/D = 1.05 ± 0.01, andJ = 0.11 ± 0.03. These results support the ideathat a reduction in diversity can be expected inmarshes colonized by Phragmites. However, thehigh diversity found in the Typha-Lythrummarshes contradicts the expectation of lower diversityafter invasion by Lythrum. This information mayalter marsh management decisions. 相似文献
11.
The montane and subalpine forests of a mountain range in northwestern Montana were investigated using phytosociological and numerical methods. Twelve associations and two subassociations were identified, of which eight are described here for the first time. The forest vegetation of valleys and lower slopes is strongly affected by repeated fire and is placed in the new orderCalamagrostio-Pseudotsugetalia glaucae, which includes temperate, low elevation forests in inland regions of northwestern North America. These forests bear only weak resemblance to forests traditionally assigned to the classVaccinio-Piceetea, and occupy the habitats filled by broad-leaved forests elsewhere at temperate latitudes. Montane and subalpine forest vegetation is moister and has longer snow duration and a shorter growing season. Upper montane vegetation more closely resembles that of other temperate montane forests of the classVaccinio-Piceetea. 相似文献
12.
Mikio Kimata 《Journal of plant research》1983,96(4):299-312
The reproductive systems of fourCardamine species were compared.C. flexuosa ssp.flexuosa, a self-pollinated winter annual in fallow paddy fields, produces numerous small seeds.C. flexuosa ssp.fallax, a self-pollinated year-long annual in gardens and roadsides, also produces many small seeds.C. impatiens, a self-pollinated annual in forest margins, similarly produces numerous small seeds.C. scutata is a self-pollinated perennial in ill-drained paddy fields and creeks; its vegetative reproduction is not predominant, and it produces relatively many seeds.C. lyrata, a cross-pollinated perennial with self-incompatibility in ill-drained paddy fields and creeks, produces fewer and heavier seeds, but it does produce many ramets. Moreover, in seed-dispersal mechanisms and germination behavior of fourCardamine species several adaptive characteristics to their habitats are found. These observations on the reproductive systems of fourCardamine species apparently present different characteristics of life-history strategy for each of them. 相似文献
13.
Azza A. Al-Musallam 《Antonie van Leeuwenhoek》1980,46(4):407-411
Aspergillus helicothrix sp. nov. is described. The species is based on a single-spore isolate obtained from the type culture of Aspergillus ellipticus Raper et Fennell. It is characterized by conspicuously echinate conidia and cup-shaped sclerotia with coiled setae. 相似文献
14.
Aspidistra albopurpurea, A. khangii, A. lubae and A. stellata discovered recently are described and illustrated as species new to science. All novelties are local endemics of northern Vietnam and southeastern Laos. Aspidistra albopurpurea is unique in the genus with a white/red stigma in striking contrast to the large milk‐white tube base. Aspidistra stellata belongs to a group of species with extraordinary long and narrow lineate perigone lobes. Aspidistra khangii and A. lubae belong to a small group of species having erect, vertical shoots. The first species is easily distinguished by its stout stem, down‐curved peduncle and obpyramidal, container‐shaped perianth. Aspidistra lubae has characteristic horizontal, peduncles and urceolate flowers. Besides the type variety, A. lubae includes var. lancifolia, which differs in its erect, lanceolate, immaculate, shortly petiolate leaves. Both varieties of A. lubae were found growing, often intermixed, in the same locality in very similar ecological conditions. 相似文献
15.
《Proteins》2024,92(5):688-688
The above article, published online on 12 June 2020 in Wiley Online Library ( wileyonlinelibrary.com ), has been retracted by agreement between the authors, the journal's Editor-in-Chief Dr. Nikolay Dokholyan, and John Wiley & Sons, Inc. The above article is a humorous editorial contribution surrounding a specialized topic, and was not intended for full online publication as part of the journal's scholarly content. Due to an editorial mistake, the above article was published online in Early View. John Wiley & Sons, Inc. takes full responsibility for the erroneous publication of this article. 相似文献
16.
First edition, 1983; 2nd edition, 1989; 3rd edition, 1994; 4thedition, 2002. Any book that appears in so many editions insuch a relatively short space of time must be doing somethingright. And so it is, for Molecular Biology of the Cell (MBoCas the authors refer to it) is arguably setting the paceandthe standardthat other textbooks on the subject mustaspire to. Although not familiar with the previous incarnationsof MBoC, I do note that the line-up 相似文献
17.
J. G. Chmielewski C. C. Chinnappa J. C. Semple 《Plant Systematics and Evolution》1990,169(3-4):123-150
Patterns of intraspecific variation were examined inAntennaria alborosea
A. E. Porsild,A. corymbosa
E. Nels,A. marginata
Greene,A. microphylla
Rydb.,A. parvifolia
Nutt., andA. umbrinella
Rydb. AlthoughA. alborosea was initially considered arctic in distribution, it became apparent that a southern montane element also exists. Our results suggest that morphological differences between arctic and southern montane specimens represent clinal variation. The additional morphological data for specimens that occur more than 1,500 km south of the species' range as it was initially described result in a better understanding of this once presumed arctic taxon. Morphological variation in the dioecious speciesA. corymbosa, A. marginata, A. microphylla, A. parvifolia, andA. umbrinella was greater between the genders than was geographic variation within each gender. These results demonstrate that both pistillate and staminate specimens must be examined in dioecious species ofAntennaria if morphological variation in the respective species is to be fully understood. Character size or number of broadly distributed species (A. microphylla andA. parvifolia) generally decreased with increasing longitude, whereas characters of species with more restricted distributions (A. alborosea, A. corymbosa, andA. marginata) generally increased in size or number with increasing latitude or longitude.Antennaria umbrinella was an exception in this respect. 相似文献
18.
《Journal of bryology》2013,35(4):270-274
AbstractA new species of Lepidopilidium (Pilotrichaceae, Hookeriales), L. crispifolium, sp. nov. from St Helena, South Atlantic Ocean is described and illustrated. 相似文献
19.
A. N. Kotlyar 《Journal of Ichthyology》2011,51(8):569-580
The second part of the publication is devoted to the Melamphaes species (family Melamphaidae), which are characterized by 20 and more rakers on the first gill arch, by seven soft rays in
the ventral fin, by absence of a temporal spine, by 14–15 rays in the pectoral fin, and by 11 abdominal vertebrae. M. polylepis is characterized by circumtropical range (Atlantic Ocean, Indian Ocean, western and central Pacific Ocean). Newly described
species M. falsidicus is described from the northern Atlantic Ocean, where it was sampled between 34°N and 58°N. Before, this species was defined
as M. microps. Another newly described species, M. pachystomus, is described along the Peruvian Coast. M. macrocephalus is redescribed. This species inhabits the eastern tropical Pacific Ocean (approximately between 30°N and 23°S). One of the
studied specimens of M. macrocephalus was characterized by larger body size (SL = 128 mm) than was described before for this species. M. leprus is known currently by single findings from the eastern tropical Atlantic Ocean (between 11°N and 4°S). This species was also
found in the samples obtain in the Gulf of Guinea. 相似文献
20.
George Poinar Jr. 《Historical Biology》2013,25(1-2):51-55
A new tribe, genus and species of straight-snouted weevils (Dominibrentus leptus, n. gen., n. sp., Dominibrentini, n. tribe; Coleoptera: Brentidae; Cyphagoginae) has been described from Dominican amber. The new taxon is characterised by compressed, ventrolateral concavities on the prothorax and abdomen and lateral concavities on the metathorax for reception of the legs. This is the first representative of a straight-snouted weevil in amber. 相似文献