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91.
FLORÉAL SOLÉ EMMANUEL GHEERBRANT MBAREK AMAGHZAZ BAÂDI BOUYA 《Zoological Journal of the Linnean Society》2009,156(4):827-846
We report here the new ‘creodont’ Lahimia selloumi gen. et sp. nov. from the late Palaeocene of the Ouled Abdoun Basin (Morocco) as the oldest known Hyaenodontidae with Tinerhodon from the Ouarzazate Basin (Morocco). By contrast to Tinerhodon, Lahimia is unexpectedly derived. Most of its specializations, such as the shortening of the anterior dentition (e.g. loss of P1) and the talonid reduction and simplification, are strikingly shared with Boualitomus from the Ypresian of the Ouled Abdoun Basin, and are distinctive from other hyaenodontids, including ‘proviverrines’. They are interpreted as synapomorphies evidencing a precociously specialized early African hyaenodontid lineage. Although Lahimia and Boualitomus remain known only by the lower dentition, their relationships with Koholia are suggested by comparison of their molar occlusal pattern. Lahimia and Boualitomus are referred to the Koholiinae, which is representative of an old African endemic lineage, as initially recognized. This remarkable lineage is characterized by synapomorphies of Lahimia and Boualitomus, and also by a shared original prevallum/postvallid shearing. The discovery of Lahimia provides direct evidence for the antiquity of the African evolution of the Hyaenodontidae. This is in agreement with an African origin of the Hyaenodontidae, and with the probable diphyletism of the ‘Creodonta’. Lahimia and the Koholiinae, as well as the diversity of the first Laurasian hyaenodontid lineages, emphasize our poor knowledge of the striking early African hyaenodontid radiation. 相似文献
92.
Roslyn Boyd Leanne Sakzewski Jenny Ziviani David F Abbott Radwa Badawy Rose Gilmore Kerry Provan Jacques-Donald Tournier Richard AL Macdonell Graeme D Jackson 《BMC neurology》2010,10(1):4
Background
Congenital hemiplegia is the most common form of cerebral palsy (CP) accounting for 1 in 1300 live births. These children have limitations in capacity to use the impaired upper limb and bimanual coordination deficits which impact on daily activities and participation in home, school and community life. There are currently two diverse intensive therapy approaches. Traditional therapy has adopted a bimanual approach (BIM training) and recently, constraint induced movement therapy (CIMT) has emerged as a promising unimanual approach. Uncertainty remains about the efficacy of these interventions and characteristics of best responders. This study aims to compare the efficacy of CIMT to BIM training to improve outcomes across the ICF for school children with congenital hemiplegia. 相似文献93.
Characterization of phosphorus fractions in the sediments of a tropical intertidal mangrove ecosystem 总被引:2,自引:0,他引:2
Solid phases of phosphorus fractions in the surface and core sediments were studied to understand the biogeochemical cycling
and bioavailability of phosphorus in the Pichavaram intertidal mangrove sediments of India. Total P in surface and core sediments
ranged between 451–552 and 459–736 μg g−1 respectively and Fe bound P was the dominant fraction. Low levels of Fe bound P in the mangrove zone than the two estuarine
zones may be because of high salinity inhibition of phosphate adsorption onto the Fe-oxides/hydroxides. Post-depositional
reorganization of P was observed in surface sediments, converting organic P and Fe bound P into the authigenic P. High levels
of organic P in the mangrove zone is primarily due to intensive cycling and degradation of organic matter and adsorption of
phosphate on the organic molecules. The burial rates and regeneration efficiency of P in the intertidal mangrove ecosystem
ranged from 5.41 to 7.27 μmol P cm−2 year−1 and 0.122 to 0.233 μmol P cm−2 year−1, respectively. High burial efficiency (≈99%) of P proves the earlier observation of limiting nature of P for the biological
productivity. Further, bioavailable P (exchangeable P + Fe bound P + organic P) constituted a considerable proportion of sedimentary
P pool of which an average accounted for 55 and 50% in surface and core sediments respectively. The results indicate that
significant amount of P is locked in sediments in the form of authigenic P and detrital P which makes P as a limiting nutrient
for the biological productivity. 相似文献
94.
Background
HTLV-I infection has been linked to lung pathology and HTLV-II has been associated with an increased incidence of pneumonia and acute bronchitis. However it is unknown whether HTLV-I or -II infection alters pulmonary function.Methods
We performed pulmonary function testing on HTLV-I, HTLV-II and HTLV seronegative subjects from the HTLV outcomes study (HOST), including vital capacity (VC), forced expiratory volume in one second (FEV1), and diffusing lung capacity for carbon monoxide (DLCO) corrected for hemoglobin and lung volume. Multivariable analysis adjusted for differences in age, gender, race/ethnicity, height and smoking history.Results
Mean (standard deviation) pulmonary function values among the 257 subjects were as follows: FVC = 3.74 (0.89) L, FEV1 = 2.93 (0.67) L, DLCOcorr = 23.82 (5.89) ml/min/mmHg, alveolar ventilation (VA) = 5.25 (1.20) L and DLCOcorr/VA = 4.54 (0.87) ml/min/mmHg/L. There were no differences in FVC, FEV1 and DLCOcorr/VA by HTLV status. For DLCOcorr, HTLV-I and HTLV-II subjects had slightly lower values than seronegatives, but neither difference was statistically significant after adjustment for confounding.Conclusions
There was no difference in measured pulmonary function and diffusing capacity in generally healthy HTLV-I and HTLV-II subjects compared to seronegatives. These results suggest that previously described HTLV-associated abnormalities in bronchoalveolar cells and fluid may not affect pulmonary function. 相似文献95.
Jason AL Jeffery Peter A Ryan Scott A Lyons Paula T Thomas Brian H Kay 《Australian Journal of Entomology》2002,41(4):329-338
Abstract We used a network of 20 carbon dioxide- and octenol-supplemented light traps to sample adult mosquitoes throughout Russell Island in southern Moreton Bay, south-east Queensland. Between February and April 2001, an estimated 1365 564 adult female mosquitoes were collected. In contrast to an average catch of 9754 female mosquitoes per trap night on Russell Island, reference traps set on Macleay Island and on the mainland returned average catches of 3172 and 222, respectively. On Russell Island, Ochlerotatus vigilax (Skuse), Coquillettidia linealis (Skuse), Culex annulirostris Skuse and Verrallina funerea (Theobald), known or suspected vectors of Ross River (RR) and/or Barmah Forest (BF) viruses, comprised 89.6% of the 25 taxa collected. When the spatial distributions of the above species were mapped and analysed using local spatial statistics, all were found to be present in highest numbers towards the southern end of the island during most of the 7 weeks. This indicated the presence of more suitable adult harbourage sites and/or suboptimal larval control efficacy. As immature stages and the breeding habitat of Cq. linealis are as yet undescribed, this species in particular presents a considerable impediment to proposed development scenarios. The method presented here of mapping the numbers of mosquitoes throughout a local government area allows specific areas that have high vector numbers to be defined. 相似文献
96.
Isospora dawadimiensis n. sp. is described from the jerboa, Jaculus jaculus, from Dawadimi, Saudi Arabia. Sporulated oocysts of I. dawadimiensis n. sp. were ovoidal or nearly subspherical 22–26.5 times 20.5–22 μm (24.4 times 21.4 μm). Oocyst wall had one layer. Micropyle, oocyst residuum, and polar granule were absent. Sporocysts were ellipsoid 12–16.5 times 9–10.5 μm (14.6 times 9.9 μm). Sporocyst residuum was present. The sporocysts lack a Stieda body. Sporozoites 8–11 times 2–3 μm (10 times 2.6 μm) were sausage-shaped, slightly curved, and tapered at one end. 相似文献
97.
M Reddy Kunduru AL Pometto III 《Journal of industrial microbiology & biotechnology》1996,16(4):249-256
Continuous ethanol fermentations were performed in duplicate for 60 days withZymomonas mobilis ATCC 331821 orSaccharomyces cerevisiae ATCC 24859 in packed-bed reactors with polypropylene or plastic composite-supports. The plastic composite-supports used contained polypropylene (75%) with ground soybean-hulls (20%) and zein (5%) forZ. mobilis, or with ground soybean-hulls (20%) and soybean flour (5%) forS. cerevisiae. Maximum ethanol productivities of 536 gL–1 h–1 (39% yield) and 499 gL–1 h–1 (37% yield) were obtained withZ. mobilis on polypropylene and plastic composite-supports of soybean hull-zein, respectively. ForZ. mobilis, and optimal yield of 50% was observed at a 1.92h–1 dilution rate for soybean hull-zein plastic composite-supports with a productivity of 96gL–1h–1, whereas with polypropylene-supports the yield was 32% and the productivity was 60gL–1h–1. With aS. cerevisiae fermentation, the ethanol production was less, with a maximum productivity of 76gL–1h–1 on the plastic composite-support at a 2.88h–1 dilution rate with a 45% yield. Polypropylene-support bioreactors were discontinued due to reactor plugging by the cell mass accumulation. Support shape (3-mm chips) was responsible for bioreactor plugging due to extensive biofilm development on the plastic composite-supports. With suspensionculture continuous fermentations in continuously-stirred benchtop fermentors, maximum productivities of 5gL–1h–1 were obtained with a yield of 24 and 26% withS. cerevisiae andZ. mobilis, respectively. Cell washout in suspensionculture continuous fermentations was observed at a 1.0h–1 dilution rate. Therefore, for continuous ethanol fermentations, biofilm reactors out-performed suspension-culture reactors, with 15 to 100-fold higher productivities (gL–1h–1) and with higher percentage yields forS. cerevisiae andZ. mobilis, respectively. Further research is needed with these novel supports to evaluate different support shapes and medium compositions that will permit medium flow, stimulate biofilm formation, reduce fermentation costs, and produce maximum yields and productivities.This is Journal Paper No. J-16357 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3253 相似文献
98.
M Reddy Kunduru AL Pometto III 《Journal of industrial microbiology & biotechnology》1996,16(4):241-248
Biofilms are a natural form of cell immobilization that result from microbial attachment to solid supports. Biofilm reactors with polypropylene composite-supports containing up to 25% (w/w) of various agricultural materials (corn hulls, cellulose, oat hulls, soybean hulls or starch) and nutrients (soybean flour or zein) were used for ethanol production. Pure cultures ofZymomonas mobilis, ATCC 31821 orSaccharomyces cerevisiae ATCC 24859 and mixed cultures with either of these ethanol-producing microorganisms and the biofilm-formingStreptomyces viridosporus T7A ATCC 39115 were evaluated. An ethanol productivity of 374g L–1 h–1 (44% yield) was obtained on polypropylene composite-supports of soybean hull-zein-polypropylene by usingZ. mobilis, whereas mixed-culture fermentations withS. viridosporus resulted in ethanol productivity of 147.5 g L–1 h–1 when polypropylene composite-supports of corn starch-soybean flour were used. WithS. cerevisiae, maximum productivity of 40 g L–1 h–1 (47% yield) was obtained on polypropylene composite-supports of soybean hull-soybean flour, whereas mixed-culture fermentation withS. viridosporus resulted in ethanol productivity of 190g L–1 h–1 (35% yield) when polypropylene composite-supports of oat hull-polypropylene were used. The maximum productivities obtained without supports (suspension culture) were 124 g L–1 h–1 and 5 g L–1 h–1 withZ. mobilis andS. cerevisiae, respectively. Therefore, forZ. mobilis andS. cerevisiae, ethanol productivities in biofilm fermentations were three- and eight-fold higher than suspension culture fermentations, respectively. Biofilm formation on the chips was detected by weight change and Gram staining of the support material at the end of the fermentation. The ethanol production rate and concentrations were consistently greater in biofilm reactors than in suspension cultures.This is Journal Paper No. J-16356 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3253 相似文献
99.
Contrasting evolutionary rates in the duplicate chaperonin genes of Mycobacterium tuberculosis and M. leprae 总被引:3,自引:0,他引:3
A phylogenetic analysis of chaperonin (heat shock protein 60) sequences
from prokaryotes and eukaryotes indicated that a single gene duplication
event in the common ancestor of Mycobacterium tuberculosis, M. leprae, and
Streptomyces albus gave rise to the duplicate chaperonin genes found in
these species (designated HSP65 and GroEL in the mycobacterial species).
Comparison of rates of synonymous and nonsynonymous nucleotide substitution
in different gene regions suggested that the 5' end of the HSP65 gene was
homogenized by an ancient recombination event between M. tuberculosis and
M. leprae. In S. albus, the two duplicated chaperonin genes have evolved at
essentially the same rate. In both M. tuberculosis and M. leprae, however,
the GroEL gene has evolved considerably more rapidly at nonsynonymous
nucleotide sites than has the HSP65 gene. Because this difference is not
seen at synonymous sites, it must be due to a difference in selective
constraint on the proteins encoded by the two genes, rather than to a
difference in mutation rate. The difference between GroEL and HSP65 is
striking in regions containing epitopes recognized by T cells of the
vertebrate host; in certain cross-reactive epitopes conserved across all
organisms, nonsynonymous sites in GroEL have evolved twice as fast as those
in HSP65. It is suggested that these differences are correlated with
differences in the way in which the duplicate chaperonins of M.
tuberculosis and M. leprae interact with the host immune system.
相似文献
100.
Sequence, organization, and evolution of the A+T region of Drosophila melanogaster mitochondrial DNA 总被引:2,自引:0,他引:2
The long (4.6-kb) A+T region of Drosophila melanogaster mitochondrial DNA
has been cloned and sequenced. The A+T region is organized in two large
arrays of tandemly repeated DNA sequence elements, with nonrepetitive
intervening and flanking sequences comprising only 22% of its length. The
first repeat array consists of five repeats of 338-373 bp. The second
consists of four intact 464-bp repeats and a fifth partial repeat of 137
bp. Three DNA sequence elements are found to be highly conserved in D.
melanogaster and in several Drosophila species with short A+T regions.
These include a 300-bp DNA sequence element that overlaps the DNA
replication origin and two thymidylate stretches identified on opposite DNA
strands. We conclude that the length heterogeneity observed in the A+T
regulatory region in mitochondrial DNAs from the genus Drosophila results
from the expansion (and contraction) of the number of repeated DNA sequence
elements. We also propose that the 300-bp conserved DNA sequence element,
in conjunction with another primary sequence determinant, perhaps the
adjacent thymidylate stretch, functions in the regulation of mitochondrial
DNA replication.
相似文献