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991.
Alan de Queiroz 《Evolution; international journal of organic evolution》1999,53(6):1654-1664
It has been suggested that image-forming eyes promote the evolutionary diversification (measured by species richness) of the groups that possess them. Several different processes could give rise to this effect, including diversifying selection in a new adaptive zone (or zones) and a reduced rate of extinction due to enhanced competitive abilities. I tested the generality of the hypothesis that imaging eyes increase net speciation by comparing extant species numbers of 12 groups that have such eyes (as categorized by Land and Fernald 1992) with those of their cladistic sister groups that lack such organs. Even assuming the published hypotheses of phylogenetic relationships that most favor increased net speciation of visual groups, these comparisons show no significant association between imaging eyes and species richness. Increased activity, as indicated by published accounts of locomotory speed, is significantly associated with the evolution of image-forming eyes. This suggests that a large “visual adaptive zone” might be characterized by relatively high activity. However, when diversity comparisons are limited to eight cases in which the evolution of imaging eyes is associated with increased activity, there is still no significant association between such eyes and species richness. The fossil record indicates that the only visual groups that have undergone major evolutionary radiations evolved imaging eyes early in the history of metazoans (before the Silurian). The radiations of these early groups may have largely filled up niches for visual animals and thus prevented the subsequent proliferation of other groups with image-forming eyes. Alternatively, it may be that image-forming eyes have no exceptional effect on diversification or that their effects are obscured by other factors in the long run. 相似文献
992.
Liana Tsiatsiani Evy Timmerman Pieter-Jan De Bock Dominique Vercammen Simon Stael Brigitte van de Cotte An Staes Marc Goethals Tine Beunens Petra Van Damme Kris Gevaert Frank Van Breusegem 《The Plant cell》2013,25(8):2831-2847
Metacaspases are distant relatives of the metazoan caspases, found in plants, fungi, and protists. However, in contrast with caspases, information about the physiological substrates of metacaspases is still scarce. By means of N-terminal combined fractional diagonal chromatography, the physiological substrates of METACASPASE9 (MC9; AT5G04200) were identified in young seedlings of Arabidopsis thaliana on the proteome-wide level, providing additional insight into MC9 cleavage specificity and revealing a previously unknown preference for acidic residues at the substrate prime site position P1′. The functionalities of the identified MC9 substrates hinted at metacaspase functions other than those related to cell death. These results allowed us to resolve the substrate specificity of MC9 in more detail and indicated that the activity of phosphoenolpyruvate carboxykinase 1 (AT4G37870), a key enzyme in gluconeogenesis, is enhanced upon MC9-dependent proteolysis. 相似文献
993.
A new species of Theletrum is described from the intestine of two palenose morays, Echidna nocturna, collected in Cuajiniquil, Guanacaste Province, Costa Rica. The new species differs from the type species, T. fustiforme Linton, 1910 by having a subspherical pars prostatica, a subspherical seminal vesicle extending anteriorly to the anterior border of the acetabulum, by the presence of a poorly developed hermaphroditic sac, and by having a larger body size. We also report eight additional species of digeneans parasitizing marine fishes in several localities along the Atlantic and Pacific coast of Costa Rica: Bianium simonei, Didymozoinae (metacercariae), Ectenurus virgulus, Hypocreadium myohelicatum, Lecithochirium microstomum, Pseudolecithaster sp., Stephanostomum casum, and Tergestia laticollis. In addition, we present an updated list of helminth parasites of marine fish from Costa Rica and discuss the importance of including parasites as an integral part of biodiversity inventories. 相似文献
994.
Loeffler SH de Vries MJ Schukken YH de Zeeuw AC Dijkhuizen AA de Graaf FM Brand A 《Theriogenology》1999,51(7):1267-1284
Technicians recorded body condition score (BCS) and several parameters related to estrus and/or metritis for 1694 first insemination cows on 23 farms. Additional variables for modeling the adjusted odds ratios (OR) for pregnancy were data on disease prior to or within 21 days of AI and test day milk yields. Significant predictors for pregnancy were farm, year and season, BCS, uterine tone, contaminated insemination gun after AI, fat-protein corrected kilograms milk (FPCM), days in milk (DIM), and diseases. Vaginal mucus, ease of cervical passage, and lameness were not significant predictors for pregnancy. Pregnancy risk at AI increased with increasing DIM, reaching a near optimum after 82 days. Lack of uterine tone was associated with a lowered pregnancy risk (OR = 0.69) as was contaminated insemination gun (OR = 0.67), first-parity lactation, FPCM >33 kg (OR = 0.71), BCS 2.5 at AI (OR = 0.65), clinical mastitis (OR = 0.53), cystic ovarian disease (OR = 0.53), and metritis (OR = 0.74). It was concluded that data on BCS and uterine findings, as collected by AI technicians, are significant predictors of AI outcome. Dairy producers and veterinarians should jointly examine the potential costs and value of such AI technician-based data to improve herd fertility. 相似文献
995.
Clonal diversity and conservation genetics of the medicinal plant Carapichea ipecacuanha (Rubiaceae)
de Oliveira LO Venturini BA Rossi AA Hastenreiter SS 《Genetics and molecular biology》2010,33(1):86-93
The roots of the understorey shrub Carapichea ipecacuanha (ipecac) have medicinal properties, and the uprooting of wild plants has supplied most of the world demand for this species. Although under severe population decline, C. ipecacuanha lacks legal protection. In the wild, the aerial stems of ipecac clump together to form clusters with well-defined borders. Cluster size may range from several to hundreds of aerial stems. To investigate the extent of clonality among aerial stems in ipecac clusters, we sampled 50 wild clusters (a total of 291 aerial stems) and screened them with 89 inter-simple sequence repeat (ISSR) markers. The 291 aerial stems were grouped into 42 putative clones. The clonal groups generally consisted of aerial stems from the same cluster, and there was little or no genetic differentiation among aerial stems at the cluster level. These findings suggest that strategies designed to conserve ipecac in situ should not rely upon census data, which are based on the number of aerial stems per cluster and the number of clusters per population, because such data greatly underestimate the species effective population size and genetic diversity. Our results also indicate that this species needs protection at a federal level. 相似文献
996.
Dipterocarpoideae, the largest sub-family of well-known plant family Dipterocarpaceae, dominates in South Asian rain forests. Although several previous studies addressed the phylogeny of the Dipterocarpaceae family, relationships among many of its genera from the Dipterocarpoideae sub-family are still not well understood. In particular, little is known about the relationships of the genera Vateriopsis, Stemonoporus, Vateria and inconsistence remains between phylogenetic results and taxonomic classifications of Shorea and Hopea species. We studied molecular phylogeny of the sub-family Dipterocarpoideae using the trnL-trnF spacer, trnL intron and the matK gene sequences of chloroplast DNA (cpDNA). This study is the first comprehensive phylogeny reconstruction for the sub-family Dipterocarpoideae based on cpDNA, as it includes most genera (14) and a large number of species (79) with most species endemic to Sri Lanka, as well as one species from Seychelles and one species from the genus Monotes from Madagascar. Phylogenetic trees were constructed using the Neighbor Joining (NJ) and Maximum Likelihood (ML) methods using combined set of sequences including all three cpDNA regions. The topologies of the NJ and ML trees were to a certain extent, consistent with the current taxonomy of Dipterocarpoideae based on morphology and with previous molecular phylogenies based on cpDNA. Furthermore, our results provided new evidence regarding the relationships of the following genera: Vateriopsis and Stemonoporus and about the validity of the previous morphology based classifications of Shorea species. In addition, the topology of our trees was consistent with the classification of Shorea species proposed by Maury (1978), Maury-Lechon (1979) and Symington (1943). Finally, our results provided evidence for the affinity of the genus Monotes to Asian Dipterocarpoideae rather than to Tiliaceae and indicated that it is a good candidate for outgroup species for future studies of the former sub-family. 相似文献
997.
Frederico Figueiredo Amancio Tiago Pires Heringer Cristina da Cunha Hueb Barata de Oliveira Liliane Boaventura Fassy Frederico Bruzzi de Carvalho Daniela Pagliari Oliveira Claudio Dornas de Oliveira Fernando Otoni Botoni Fernanda do Carmo Magalh?es José Roberto Lambertucci Mariangela Carneiro 《PloS one》2015,10(6)
The purpose of our study was to describe the clinical profile of dengue-infected patients admitted to Brazilian intensive care units (ICU) and evaluate factors associated with death. A longitudinal, multicenter case series study was conducted with laboratory-confirmed dengue patients admitted to nine Brazilian ICUs situated in Minas Gerais state, southeastern Brazil from January 1, 2008, to December 31, 2013. Demographic, clinical and laboratory data; disease severity scores; and mortality were evaluated. A total of 97 patients were studied. The in-ICU and in-hospital mortality rates were 18.6% and 19.6%, respectively. Patients classified as having severe dengue according to current World Health Organization classifications showed an increased risk of death in a univariate analysis. Nonsurvivors were older, exhibited lower serum albumin concentrations and higher total leukocyte counts and serum creatinine levels. Other risk factors (vomiting, lethargy/restlessness, dyspnea/respiratory distress) were also associated with death in a univariate analysis. Multivariate analysis indicated that in-hospital mortality was significantly associated with Acute Physiology and Chronic Health Evaluation II and the Sequential Organ Failure Assessment score. The ICU and in-hospital mortality observed in this study were higher than values reported in similar studies. An increased frequency of ICU admission due to severe organ dysfunction, higher severity indices and scarcity of ICU beds may partially explain the higher mortality. 相似文献
998.
David C. Bartholomew Paulo R. L. Bittencourt Antonio C. L. da Costa Lindsay F. Banin Patrícia de Britto Costa Sarah I. Coughlin Tomas F. Domingues Leandro V. Ferreira André Giles Maurizio Mencuccini Lina Mercado Raquel C. Miatto Alex Oliveira Rafael Oliveira Patrick Meir Lucy Rowland 《Plant, cell & environment》2020,43(10):2380-2393
The response of small understory trees to long-term drought is vital in determining the future composition, carbon stocks and dynamics of tropical forests. Long-term drought is, however, also likely to expose understory trees to increased light availability driven by drought-induced mortality. Relatively little is known about the potential for understory trees to adjust their physiology to both decreasing water and increasing light availability. We analysed data on maximum photosynthetic capacity (Jmax, Vcmax), leaf respiration (Rleaf), leaf mass per area (LMA), leaf thickness and leaf nitrogen and phosphorus concentrations from 66 small trees across 12 common genera at the world's longest running tropical rainfall exclusion experiment and compared responses to those from 61 surviving canopy trees. Small trees increased Jmax, Vcmax, Rleaf and LMA (71, 29, 32, 15% respectively) in response to the drought treatment, but leaf thickness and leaf nutrient concentrations did not change. Small trees were significantly more responsive than large canopy trees to the drought treatment, suggesting greater phenotypic plasticity and resilience to prolonged drought, although differences among taxa were observed. Our results highlight that small tropical trees have greater capacity to respond to ecosystem level changes and have the potential to regenerate resilient forests following future droughts. 相似文献
999.
Menke de Smit Johanna Westra Arjan Vissink Berber Doornbos-van der Meer Elisabeth Brouwer Arie Jan van Winkelhoff 《Arthritis research & therapy》2012,14(5):R222
Introduction
The association between rheumatoid arthritis (RA) and periodontitis is suggested to be linked to the periodontal pathogen Porphyromonas gingivalis. Colonization of P. gingivalis in the oral cavity of RA patients has been scarcely considered. To further explore whether the association between periodontitis and RA is dependent on P. gingivalis, we compared host immune responses in RA patients with and without periodontitis in relation to presence of cultivable P. gingivalis in subgingival plaque.Methods
In 95 RA patients, the periodontal condition was examined using the Dutch Periodontal Screening Index for treatment needs. Subgingival plaque samples were tested for presence of P. gingivalis by anaerobic culture technique. IgA, IgG and IgM antibody titers to P. gingivalis were measured by ELISA. Serum and subgingival plaque measures were compared to a matched control group of non-RA subjects.Results
A higher prevalence of severe periodontitis was observed in RA patients in comparison to matched non-RA controls (27% versus 12%, p < 0.001). RA patients with severe periodontitis had higher DAS28 scores than RA patients with no or moderate periodontitis (p < 0.001), while no differences were seen in IgM-RF or ACPA reactivity. Furthermore, RA patients with severe periodontitis had higher IgG- and IgM-anti P. gingivalis titers than non-RA controls with severe periodontitis (p < 0.01 resp. p < 0.05), although subgingival occurrence of P. gingivalis was not different.Conclusions
Severity of periodontitis is related to severity of RA. RA patients with severe periodontitis have a more robust antibody response against P. gingivalis than non-RA controls, but not all RA patients have cultivable P. gingivalis. 相似文献1000.
Marta Coll Chiara Piroddi Camille Albouy Frida Ben Rais Lasram William W. L. Cheung Villy Christensen Vasiliki S. Karpouzi François Guilhaumon David Mouillot Michelle Paleczny Maria Lourdes Palomares Jeroen Steenbeek Pablo Trujillo Reg Watson Daniel Pauly 《Global Ecology and Biogeography》2012,21(4):465-480
Aim A large body of knowledge exists on individual anthropogenic threats that have an impact on marine biodiversity in the Mediterranean Sea, although we know little about how these threats accumulate and interact to affect marine species and ecosystems. In this context, we aimed to identify the main areas where the interaction between marine biodiversity and threats is more pronounced and to assess their spatial overlap with current marine protected areas in the Mediterranean. Location Mediterranean Sea. Methods We first identified areas of high biodiversity of marine mammals, marine turtles, seabirds, fishes and commercial or well‐documented invertebrates. We mapped potential areas of high threat where multiple threats are occurring simultaneously. Finally we quantified the areas of conservation concern for biodiversity by looking at the spatial overlap between high biodiversity and high cumulative threats, and we assessed the overlap with protected areas. Results Our results show that areas with high marine biodiversity in the Mediterranean Sea are mainly located along the central and north shores, with lower values in the south‐eastern regions. Areas of potential high cumulative threats are widespread in both the western and eastern basins, with fewer areas located in the south‐eastern region. The interaction between areas of high biodiversity and threats for invertebrates, fishes and large animals in general (including large fishes, marine mammals, marine turtles and seabirds) is concentrated in the coastal areas of Spain, Gulf of Lions, north‐eastern Ligurian Sea, Adriatic Sea, Aegean Sea, south‐eastern Turkey and regions surrounding the Nile Delta and north‐west African coasts. Areas of concern are larger for marine mammal and seabird species. Main conclusions These areas may represent good candidates for further research, management and protection activities, since there is only a maximum 2% overlap between existing marine protected areas (which cover 5% of the Mediterranean Sea) and our predicted areas of conservation concern for biodiversity. 相似文献