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1.
A new species of Trichomyia from the state of Bahia, Brazil, is described and illustrated, and male and female are associated using DNA barcoding. Additionally, fragments of the COI of two other species, Trichomyia cerdosa Araújo & Bravo, 2016 and Trichomyia ituberensis Araújo & Bravo, 2016, and the females of two unidentified species, are sequenced.  相似文献   

2.
A study of the 26 Cyperaceae published in G. Raddi’s Agrostografia brasiliensis is presented. Several new synonyms and a re-evaluation of some taxa described by G. Raddi are proposed. The first citation of Fimbristylis pilosa Vahl for Brazil is reported. The new combination, Pleurostachys pilulifera (Bertol.) Longhi-Wagner, Baldini & A. C. Araújo is made.  相似文献   

3.
A new species is here described: Scleria rubrostriata A. C. Araújo & N. A. Brummitt, a herb from the Atlantic forest of Espírito Santo State, south-eastern Brazil. A key to the sections of Scleria and to the American species of Scleria sect. Schizolepis is provided, and an illustration of the new species and comparison to similar taxa are given.  相似文献   

4.
Biodiversity assessment requires that we use surrogate information in practice to indicate more general biodiversity patterns. ‘ED’ refers to a surrogates framework that can link species data and environmental information based on a robust relationship of compositional dissimilarities to ordinations that indicate underlying environmental variation. In an example analysis of species and environmental data from Panama, the environmental and spatial variables that correlate with an hybrid multi‐dimensional scaling ordination were able to explain 83% of the variation in the corresponding Bray Curtis dissimilarities. The assumptions of ED also provide the rationale for its use of p‐median optimization criteria to measure biodiversity patterns among sites in a region. M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1) have re‐named ED as ‘AD’ in their evaluation of the surrogacy value of ED based on European species data. Because lessons from previous work on ED options consequently may have been neglected, we use a corroboration framework to investigate the evidence and ‘background knowledge’ presented in their evaluations of ED. Investigations focus on the possibility that their weak corroboration of ED surrogacy (non‐significance of target species recovery relative to a null model) may be a consequence of Araújo et al.'s use of particular evidence and randomizations. We illustrate how their use of discrete ED, and not the recommended continuous ED, may have produced unnecessarily poor species recovery values. Further, possible poor optimization of their MDS ordinations, due to small numbers of simulations and/or low resolution of stress values appears to have provided a possible poor basis for ED application and, consequently, may have unnecessarily favoured non‐corroboration results. Consideration of Araújo et al.'s randomizations suggests that acknowledged sampling biases in the European data have not only artefactually promoted the non‐significance of ED recovery values, but also artefactually elevated the significance of competing species surrogates recovery values. We conclude that little credence should be given to the comparisons of ED and species‐based complementarity sets presented in M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1), unless the factors outlined here can be analysed for their effects on results. We discuss the lessons concerning surrogates evaluation emerging from our investigations, calling for better provision in such studies of the background information that can allow (i) critical examination of evidence (both at the initial corroboration and re‐evaluation stages), and (ii) greater synthesis of lessons about the pitfalls of different forms of evidence in different contexts.  相似文献   

5.
Araújo, T.H., Faria, F.P., Katchburian, E. and Freymüller, E. (2009). Ultrastructural changes in skeletal muscle of the tail of the lizard Hemidactylus mabouia immediately following autotomy. —Acta Zoologica (Stockholm) 91 : 440–446. Although autotomy and subsequent regeneration of lizard tails has been extensively studied, there is little information available on ultrastructural changes that occur to the muscle fibers at the site of severance. Thus, in the present study, we examine the ultrastructure of the musculature of the remaining tail stump of the lizard Hemidactylus mabouia immediately after autotomy. Our results show that exposed portions of the skeletal muscle fibers of the stump that are unprotected by connective tissue bulge to produce large mushroom‐like protrusions. These exposed portions show abnormal structure but suffer no leakage of cytoplasmic contents. Many small and large vesicular structures appeared between myofibrils in the interface at this disarranged region (distal) and the other portion of the fibers that remain unchanged (proximal). These vesicles coalesce, creating a gap that leads to the release of the mushroom‐like protrusion. So, our results showed that after the macroscopic act of autotomy the muscular fibers release part of the sarcoplasm as if a second and microscopic set of autotomic events takes place immediately following the macroscopic act of autotomy. Presumably these changes pave the way for the formation of a blastema and the beginning of regeneration.  相似文献   

6.
 Neural oscillation is one of the most extensively investigated topics of artificial neural networks. Scientific approaches to the functionalities of both natural and artificial intelligences are strongly related to mechanisms underlying oscillatory activities. This paper concerns itself with the assumption of the existence of central pattern generators (CPGs), which are the plausible neural architectures with oscillatory capabilities, and presents a discrete and generalized approach to the functionality of locomotor CPGs of legged animals. Based on scheduling by multiple edge reversal (SMER), a primitive and deterministic distributed algorithm, it is shown how oscillatory building block (OBB) modules can be created and, hence, how OBB-based networks can be formulated as asymmetric Hopfield-like neural networks for the generation of complex coordinated rhythmic patterns observed among pairs of biological motor neurons working during different gait patterns. It is also shown that the resulting Hopfield-like network possesses the property of reproducing the whole spectrum of different gaits intrinsic to the target locomotor CPGs. Although the new approach is not restricted to the understanding of the neurolocomotor system of any particular animal, hexapodal and quadrupedal gait patterns are chosen as illustrations given the wide interest expressed by the ongoing research in the area. Received: 14 June 2002 / Accepted: 18 February 2003 / Published online: 20 May 2003 Correspondence to: Z. Yang (e-mail: zhijun.yang@ed.ac.uk) Acknowledgements. This work was partially supported by CNPq, the Brazilian Research Agency, under support number 143032/96-8. We are grateful for the helpful discussions with Prof. V.C. Barbosa, Dr. A.E. Xavier, Dr. M.S. Dutra, and Dr. A.F.R. Araújo. The donations of FPGA hardware and software from XILINX Incorporation under the order No. XUP2930 and XUP3576 are also highly appreciated.  相似文献   

7.
D. C. H. PLOWES 《Ostrich》2013,84(2):134-154
Catry, P., Araújo, A., Cruz, C., Pinheiro, A., Poças, M., Nadum, J., Armelin, M.&; Pereira, J.R. 1999. Are mist-nets suitable for rapid habitat evaluations in the tropics? Results from a study in Guyinea-Bissau. Ostrich 70(2) 134–137

There is an increasing need for rapid habitat evaluations, in the tropics, for conservation purposes. Biodiversity is often assessed by studying relatively well known groups, such as birds. But even birds can be difficult to watch and identify in tropical habitats. Mist-netting is relatively free of observer bias, and allows sampling effort to be standardised. We sampled birds by mist-netting in seven wooded habitats, covering a wide range of levels of anthropogenic disturbance, in the Cufada region, Guinea Bissau. Capture rates, species diversity (as estimated by rarefaction) and originality of the bird communities appeared to be higher in disturbed habitats. Primary forest had the lowest capture rate and the lowest diversity index. Originality was also very low in primary forest. We discuss several possible causes for these patterns and argue that surveys based exclusively on mist-netting can be severely misleading, when comparing bird communities in different habitats.  相似文献   

8.
Dinoflagellates are a highly diverse and environmentally important group of protists with relatively poor resolution of phylogenetic relationships, particularly among heterotrophic species. We examined the phylogeny of several dinophysiacean dinoflagellates using samples collected from four Atlantic sites. As a rule, 3.5 kb of sequence including the nuclear ribosomal genes SSU, 5.8S, LSU, plus their internal transcribed spacer (ITS) 1 and 2 regions were determined for 26 individuals, including representatives of two genera for which molecular data were previously unavailable, Ornithocercus F. Stein and Histioneis F. Stein. In addition, a clone library targeting the dinophysiacean ITS2 and LSU sequences was constructed from bulk environmental DNA from three sites. Three phylogenetic trees were inferred from the data, one using data from this study for cells identified to genus or species (3.5 kb, 28 taxa); another containing dinoflagellate SSU submissions from GenBank and the 12 new dinophysiacean sequences (1.9 kb, 56 taxa) from this study; and the third tree combing data from identified taxa, dinophysiacean GenBank submissions, and the clone libraries from this study (2.1 kb, 136 taxa). All trees were congruent and indicated a distinct division between the genera Phalacroma F. Stein and Dinophysis Ehrenb. The cyanobionts containing genera Histioneis and Ornithocercus were also monophyletic. This was the largest molecular phylogeny of dinophysoid taxa performed to date and was consistent with the view that the genus Phalacroma may not be synonymous with Dinophysis.  相似文献   

9.
10.
Abstract.  The anthomyiid fly genus Coenosopsia Malloch contained five species geographically restricted to the forests of the New World, from southern U.S.A. to southeastern Brazil and Paraguay. Two new species are described here from the Brazilian Cerrado: C. ferrari sp.n. and C. michelseni sp.n. Viviparity in C. brasiliensis Michelsen and C. peruviana Michelsen is reported and discussed. A cladistic analysis of the genus was performed using Fannia bahiensis Albuquerque (Fanniidae), Polietina orbitalis (Stein) (Muscidae), Anthomyia pluripunctata (Albuquerque), Delia platura (Meigen) and Phaonantho benevola Couri (Anthomyiidae) as outgroups. The analysis was carried out using three character weighting schemes: equal, successive and implied weighting. In the phylogenetic relationship (( C. ferrari , C. brasiliensis ) ( C. peruviana ( C. prima ( C. michelseni ( C. floridensis , C. mexicana ))))), two major clades were found, one distributed mainly in southeastern South America and the other from northwestern South America to southern North America. Reconciling the phylogeny with the available distributional data, a biogeographical analysis of the genus is proposed and discussed. The pattern found for Coenosopsia corroborated a previously proposed model of vicariance events for the Neotropical region. Although the presence of anthomyiid fauna in the region was explained previously on the basis of the North-to-South America dispersal, we suggest an alternative hypothesis, that of a Gondwanan origin for the Neotropical anthomyiids.  相似文献   

11.
Prairie Voices: Process Anthropology in Family Medicine. Howard F. Stein. Westport, CT: Bergin & Gavey. 1996. xxii. 137.  相似文献   

12.
Twenty-nineFusarium isolates, representing three new taxa originated by Nirenberg fromF. sambucinum Fuckel sensu lato, namely:F. sambucinum Fuckel sensu stricto,F. venenotum Nirenb., andF. torulosum (Berk. & Curt.) Nirenb., were tested for in vitro production of toxic secondary metabolites on autoclaved corn kernels.F. sambucinum sensu stricto was able to produce type A trichothecenes and enniatin B (EB). In particular, amongst the 14 isolates tested, 5 produced only diacetoxyscirpenol (DAS) (up to 700 µg/g); 1 produced only neosolaniol (NEOS) (250 µg/g); 2 produced T-2 toxin (T-2) + NEOS (up to 175 and 150 µg/g, respectively); 1 produced NEOS + DAS (300 and 100 µg/g, respectively); and 5 produced DAS + EB (up to 500 and 140 µg/g, respectively). All six isolates ofF. venenotum were able to produce only DAS (up to 100 µg/g).F. torulosum produced no trichothecenes, but four out of nine tested isolates were able to produce EB (up to 140 µg/g). Zearalenones and type B trichothecenes were not found. The toxicity of the culture extracts towardsArtemia salina L. was correlated in general with the occurrence of the above toxins, except for someF. torulosum strains. However, the lack of correlation between the amounts of toxins recovered and toxic activity observed in theGeotrichum candidum Link ex Pers. andA. salina assays suggested the presence of unknown toxic compounds.  相似文献   

13.
The reproductive cycle and parasitism in the clam Anomalocardia brasiliana were studied in two different areas, an intermediate beach (Cidade) and a tidal flat (Araçá), in Southeast Brazil. Four gametogenic stages were described for males and females in both areas. Mature and spawning individuals were present throughout the period of study at Cidade and Araçá; however, major temporal differences were recorded between sites. Whereas only a few individuals in the resting stage were recorded at Cidade throughout the study period, resting stage individuals were frequent at Araçá. Moreover, a shorter period of gametogenesis was observed at Araçá than at Cidade. Oocyte number was the most effective parameter to differentiate gametogenic stages. An unidentified digenetic trematode was the only parasite infecting A. brasiliana at the study sites, and caused castration of all hosts. Parasite prevalence (proportion of infected hosts) was similar and low (ca 7.5%) at Cidade and Araçá and therefore is not expected to compromise the reproductive output of these populations. Comparison with data from previous studies suggests a latitudinal pattern for the reproductive biology of A. brasiliana, with resting stages occurring only at two high-latitude sites; however, no evidence was found for a latitudinal pattern of trematode prevalence in this species.  相似文献   

14.
Five species previously included inForsstroemia Lindb. are excluded:F. leptodontoidea Buck is a synonym ofMiyabea fruticella (Mitt.) Broth. (Thuidiaceae);F. rigida Dix. becomesNeolindbergia plicata Stark & Buck, nom. nov. (Prionodontaceae);F. dixonii Tosco & Piovano is a synonym ofLevierella fabroniacea C. Müll. (Fabroniaceae);F. filiformis M. X. Zhang becomesLeptopterigynandrum filiforme (M. X. Zhang) Stark & Buck, comb. nov. (Leskeaceae); andF. secunda Dix. & Badhw. is placed in a new genus,Bryonorrisia Stark & Buck, asB. secunda (Dix. & Badhw.) Stark & Buck, comb. nov. (Anomodontaceae).  相似文献   

15.
A fosmid library with inserts containing approximately 40 kb of marine bacterial DNA (J. L. Stein, T. L. Marsh, K. Y. Wu, H. Shizuya, and E. F. DeLong, J. Bacteriol. 178:591–599, 1996) yielded four clones with 16S rRNA genes from the order Planctomycetales. Three of the clones belong to the Pirellula group and one clone belongs to the Planctomyces group, based on phylogenetic and signature nucleotide analyses of full-length 16S rRNA genes. Sequence analysis of the ends of the genes revealed a consistent mismatch in a widely used bacterium-specific 16S rRNA PCR amplification priming site (27F), which has also been reported in some thermophiles and spirochetes.  相似文献   

16.
The Lispe longicollis species-group is revised. Lispe ethiopica sp. n. is described. The following 3 new synonyms are established: Lispe assimilis Wiedemann, 1824 (syn: cyrtoneurina Stein, 1900 and modesta Stein, 1913); Lispe manicata Wiedemann, 1830 (syn: forficata Kurahashi & Shinonaga, 2009). Female of Lispe microptera Seguy, 1937 is described for the first time. Identification key for known Eurasian and African species is given.  相似文献   

17.
Transgenic tomato plants were constructed with an empty vector (EV) or a vector expressing an apoA-I mimetic peptide, 6F. EV or 6F tomatoes were harvested, lyophilized, ground into powder, added to Western diet (WD) at 2.2% by weight, and fed to LDL receptor-null (LDLR−/−) mice at 45 mg/kg/day 6F. After 13 weeks, the percent of the aorta with lesions was 4.1 ± 4%, 3.3 ± 2.4%, and 1.9 ± 1.4% for WD, WD + EV, and WD + 6F, respectively (WD + 6F vs. WD, P = 0.0134; WD + 6F vs. WD + EV, P = 0.0386; WD + EV vs. WD, not significant). While body weight did not differ, plasma serum amyloid A (SAA), total cholesterol, triglycerides, and lysophosphatidic acid (LPA) levels were less in WD + 6F mice; P < 0.0295. HDL cholesterol and paroxonase-1 activity (PON) were higher in WD + 6F mice (P = 0.0055 and P = 0.0254, respectively), but not in WD + EV mice. Plasma SAA, total cholesterol, triglycerides, LPA, and 15-hydroxyeicosatetraenoic acid (HETE) levels positively correlated with lesions (P < 0.0001); HDL cholesterol and PON were inversely correlated (P < 0.0001). After feeding WD + 6F: i) intact 6F was detected in small intestine (but not in plasma); ii) small intestine LPA was decreased compared with WD + EV (P < 0.0469); and iii) small intestine LPA 18:2 positively correlated with the percent of the aorta with lesions (P < 0.0179). These data suggest that 6F acts in the small intestine and provides a novel approach to oral apoA-I mimetic therapy.  相似文献   

18.
The effect of additional information on image shape classification was studied in seven-year-old children. The classified images were either dissimilar in the axis ratio of the basic oval (F) or had an additional element (F + E). In one series of experiments, the additional element was oriented towards a longer axis of the oval, which was a discriminative sign (situation 1, matching); in another series it was rotated by 90° (situation 2, mismatching). The analysis of the successful image classification in series 1 and 2 showed that images with an additional element that mismatches a discriminative sign were classified as being significantly worse than those with matching information. The analysis of the event-related potentials (ERP) from different cortical areas revealed a specific role of the frontal and temporo-parieto-occipital cortical areas in the classification of additional sensory information. The analysis of additional matching information (series 1) was associated with the right hemisphere and evidenced by an increase in N200 wave amplitude in the frontal area and by a negative shift during the development of a late positive complex (250–550 ms) in the temporo-parieto-occipital area. The analysis of additional information mismatching a discriminative sign (series 2) was associated with the left hemisphere and evidenced by an early positive component (P100) in the frontal area, negative components N200–N250, and a further negative shift during the development of late positive complex in the temporo-parieto-occipital area.  相似文献   

19.
Almost 80 years ago, a radiation scheme based on structural resemblance was first outlined for the marine order Dinophysiales. This hypothetical radiation illustrated the relationship between the dinophysioid genera and included several independent, extant lineages. Subsequent studies have supplied additional information on morphology and ecology to these evolutionary lineages. We have for the first time combined morphological information with molecular phylogenies to test the dinophysioid radiation hypothesis in a modern context. Nuclear‐encoded LSU rDNA sequences including domains D1‐D6 from 27 species belonging to Dinophysis Ehrenb., Ornithocercus F. Stein, Phalacroma F. Stein, Amphisolenia F. Stein, Citharistes F. Stein, and Histioneis F. Stein were obtained from the Indian Ocean. Previously, LSU rDNA has only been determined from one of these. In Bayesian analyses, Amphisolenia formed a long basal clade to the other dinophysioids. These diverged into two separate lineages, the first comprised species with a classical Phalacroma outline, also including the type species P. porodictyum F. Stein. Thus, we propose to reinstate the genus Phalacroma. The relationship between the genera in the second lineage was not well resolved. However, the molecular phylogeny supported monophyly of Histioneis and Citharistes and showed the genus Dinophysis to be polyphyletic and in need of a taxonomic revision. Species of Ornithocercus grouped with Citharistes, but this relationship remained unresolved. The phylogenetic trees furthermore revealed convergent evolution of several morphological characters in the dinophysioids. According to the molecular data, the dinophysioids appeared to have evolved quite differently from the radiation schemes previously hypothesized. Four dinophysioid species had identical LSU rDNA sequences to other well‐established species.  相似文献   

20.
This study tested the hypothesis that increased oestradiol secretion by large follicles in the ovary ipsilateral to the previously gravid uterine horn has a local effect to increase the rate of uterine involution. Cows were administered an i.m. water placebo (n = 19), 250 iu equine chorionic gonadotrophin (eCG) (n = 18) or 750 iu eCG (n = 20) 14 days post partum (day 0). Transrectal ultrasonography at the time of treatment and 2, 4 and 6 days later monitored uterine horn diameter and ovarian structures. Blood samples collected contemporaneously were assayed for 15-keto-13, 14-dihydro-prostaglandin F(2alpha) and oestradiol concentration. For control cows, accumulated diameter of the largest follicle in the ovary ipsilateral to the previously gravid uterine horn, compared with the contralateral ovary, was smaller on day 0 (P < 0.05) and days 2, 4 and 6 (P < 0.001). There were no significant differences in the eCG-treated animals. There were 12, 8 and 11 cows with a plasma oestradiol concentration < 1 pg ml(-1) on day 0 in the control, 250 and 750 iu eCG treatment groups, respectively. For control cows, the peripheral oestradiol concentrations were higher on day 6 compared with days 0, 2 and 4 (P < 0.05); for cows treated with 250 iu eCG, concentrations were higher on days 4 and 6 compared with day 0 (P < 0.05); and for cows treated with 750 iu eCG, concentrations were higher on days 2 and 4 compared with day 0 (P < 0.01). Treatment with eCG, or the presence of a follicle > 8 mm in diameter in the ovary ipsilateral to the previously gravid uterine horn, did not affect the rate of uterine involution or plasma 15-keto-13,14-dihydro-prostaglandin F(2alpha) concentration. In conclusion, administration of eCG to increase follicular growth and oestradiol production overcame the inhibition of follicular growth in the ovary ipsilateral to the previously gravid uterine horn, but did not affect uterine involution.  相似文献   

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