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61.
62.
Seabirds in expanding colonies select the highest-quality nesting habitat, but habitat selection has seldom been studied in declining colonies. We studied a colony of Magellanic penguins (Spheniscus magellanicus) that declined from 314,000 active nests in 1987 to 201,000 in 2014. As expected, nest quality and reproductive success were higher in burrow habitats than in other habitats, and nest density decreased with distance from shore. Contrary to predictions, the steepest declines did not occur in the poorest-quality habitat (scrub) or near the inland colony edge and the colony area did not shrink. In agreement with predictions, penguins shifted from nests with less cover to nests with more cover. The highest nest densities and the steepest declines were in habitats of large bushes and bush clusters. As the population declined penguins abandoned nests on the edges of large bushes. Constraints on penguin habitat-use changes include strong area and nest-site fidelity, increased avian predation in high-density areas, soil characteristics, and the costs of making and maintaining nests. Contrary to conventional wisdom we found low-density, poor-quality scrub habitat (which covers >70 % of the colony area) contained 45 % of active nests, produced 44 % of fledglings, and was as important as high-quality habitat for reproductive output. Our research shows that all habitats in a declining colony of seabirds have value for conservation. 相似文献
63.
Precocious flowering of juvenile citrus induced by a viral vector based on Citrus leaf blotch virus: a new tool for genetics and breeding 总被引:1,自引:0,他引:1 下载免费PDF全文
Karelia Velázquez Jesús Agüero María C. Vives Pablo Aleza José A. Pina Pedro Moreno Luis Navarro José Guerri 《Plant biotechnology journal》2016,14(10):1976-1985
The long juvenile period of citrus trees (often more than 6 years) has hindered genetic improvement by traditional breeding methods and genetic studies. In this work, we have developed a biotechnology tool to promote transition from the vegetative to the reproductive phase in juvenile citrus plants by expression of the Arabidopsis thaliana or citrus FLOWERING LOCUS T (FT) genes using a Citrus leaf blotch virus‐based vector (clbvINpr‐AtFT and clbvINpr‐CiFT, respectively). Citrus plants of different genotypes graft inoculated with either of these vectors started flowering within 4–6 months, with no alteration of the plant architecture, leaf, flower or fruit morphology in comparison with noninoculated adult plants. The vector did not integrate in or recombine with the plant genome nor was it pollen or vector transmissible, albeit seed transmission at low rate was detected. The clbvINpr‐AtFT is very stable, and flowering was observed over a period of at least 5 years. Precocious flowering of juvenile citrus plants after vector infection provides a helpful and safe tool to dramatically speed up genetic studies and breeding programmes. 相似文献
64.
Focal adhesion kinase: predictor of tumour response and risk factor for recurrence after neoadjuvant chemoradiation in rectal cancer 下载免费PDF全文
Maria Jesús Fernández‐Aceñero Aurea Borrero‐Palacios Laura del Puerto‐Nevado Javier Martínez‐Useros Juan Pablo Marín‐Arango Cristina Caramés Ricardo Vega‐Bravo María Rodríguez‐Remírez Marlid Cruz‐Ramos Félix Manzarbeitia Jesús García‐Foncillas 《Journal of cellular and molecular medicine》2016,20(9):1729-1736
Rectal cancer represents about 30% of colorectal cancers, being around 50% locally advanced at presentation. Chemoradiation (CRT) followed by total mesorectal excision is the standard of care for these locally advanced stages. However, it is not free of adverse effects and toxicity and the complete pathologic response rate is between 10% and 30%. This makes it extremely important to define factors that can predict response to this therapy. Focal adhesion kinase (FAK) expression has been correlated with worse prognosis in several tumours and its possible involvement in cancer radio‐ and chemosensitivity has been suggested; however, its role in rectal cancer has not been analysed yet. To analyse the association of FAK expression with tumour response to CRT in locally advanced rectal cancer. This study includes 73 patients with locally advanced rectal cancer receiving standard neoadjuvant CRT followed by total mesorectal excision. Focal adhesion kinase protein levels were immunohistochemically analysed in the pre‐treatment biopsies of these patients and correlated with tumour response to CRT and patients survival. Low FAK expression was significantly correlated with local and distant recurrence (P = 0.013). Low FAK expression was found to be a predictive marker of tumour response to neoadjuvant therapy (P = 0.007) and patients whose tumours did not express FAK showed a strong association with lower disease‐free survival (P = 0.01). Focal adhesion kinase expression predicts neoadjuvant CRT response in rectal cancer patients and it is a clinically relevant risk factor for local and distant recurrence. 相似文献
65.
Problems with supertrees based on the subtree prune‐and‐regraft distance,with comments on majority rule supertrees 下载免费PDF全文
Pablo A. Goloboff Claudia A. Szumik 《Cladistics : the international journal of the Willi Hennig Society》2016,32(1):82-89
This paper examines a recent proposal to calculate supertrees by minimizing the sum of subtree prune‐and‐regraft distances to the input trees. The supertrees thus calculated may display groups present in a minority of the input trees but contradicted by the majority, or groups that are not supported by any input tree or combination of input trees. The proponents of the method themselves stated that these are serious problems of “matrix representation with parsimony”, but they can in fact occur in their own method. The majority rule supertrees, being explicitly clade‐based, cannot have these problems, and seem much more suited to retrieving common clades from a set of trees with different taxon sets. However, it is dubious that so‐called majority rule supertrees can always be interpreted as displaying those clades present (or compatible with) with a majority of the trees. The majority rule consensus is always a median tree, in terms of the Robinson–Foulds distances (i.e. it minimizes the sum of Robinson–Foulds distances to the input trees). In contrast, majority rule supertrees may not be median—different, contradictory trees may minimize Robinson–Foulds distances, while their strict consensus does not. If being “majority” results from being median in Robinson–Foulds distances, this means that in the supertree setting a “majority” is ambiguously defined, sometimes achievable only by mutually contradictory trees. 相似文献
66.
Santiago José Fernandez Pablo Yorio Javier Ernesto Ciancio 《Marine Biology Research》2019,15(1):84-96
The Magellanic Penguin (Spheniscus magellanicus) is the most abundant and widely distributed seabird breeding on the Patagonian Coast of Argentina. We combined conventional stomach content and stable isotope analysis to assess Magellanic Penguin diet during the chick rearing stage at the two northernmost colonies in an area subject to fisheries. In 2011 and 2013, Thornfish (Bovichtus argentinus) was the main prey by mass at Complejo Islote Lobos (63.0% and 32.3%, respectively) and Argentine Anchovy (Engraulis anchoita) at Estancia San Lorenzo (85.2 and 63.3%, respectively). Magellanic Penguins from both colonies showed low isotopic niche overlap in 2011 (36%) and no overlap in 2013, suggesting a different use of prey species and/or foraging areas. Stable isotope mixing models showed that Argentine Anchovy (52.8%) and Thornfish (65.9%) were the main prey at Complejo Islote Lobos in 2011 and 2013, respectively, while Patagonian Redfish (Sebastes oculatus) (46.4%) and Squat Lobster (Munida gregaria) (50%) were the main prey at Estancia San Lorenzo in 2011 and 2013, respectively. Results show that in addition to Argentine Anchovy, previously recognized as main prey for breeding Magellanic Penguins in northern Patagonia, other juvenile or small sized fish are important diet items. Diet results suggest different scenarios of food conditions for each colony, despite the relative short distance between breeding locations. The low contribution of Argentine Hake (Merluccius hubbsi) and Argentine Shortfin Squid (Illex argentinus) suggests a low trophic overlap with commercial fisheries. The information provided is key to understand changes in the marine ecosystem and potential penguin-fishery interactions. 相似文献
67.
Solange Duruz Natalia Sevane Oliver Selmoni Elia Vajana Kevin Leempoel Sylvie Stucki Pablo Orozco‐terWengel Estelle Rochat Susana Dunner Michael W. Bruford Stphane Joost 《Molecular ecology resources》2019,19(5):1355-1365
sam βada is a genome–environment association software, designed to search for signatures of local adaptation. However, pre‐ and postprocessing of data can be labour‐intensive, preventing wider uptake of the method. We have now developed R.SamBada, an r ‐package providing a pipeline for landscape genomic analysis based on sam βada , spanning from the retrieval of environmental conditions at sampling locations to gene annotation using the Ensembl genome browser. As a result, R.SamBada standardizes the landscape genomics pipeline and eases the search for candidate genes of local adaptation, enhancing reproducibility of landscape genomic studies. The efficiency and power of the pipeline is illustrated using two examples: sheep populations from Morocco with no evident population structure and Lidia cattle from Spain displaying population substructuring. In both cases, R.SamBada enabled rapid identification and interpretation of candidate genes, which are further discussed in the light of local adaptation. The package is available in the r CRAN package repository and on GitHub (github.com/SolangeD/R.SamBada). 相似文献
68.
Milagros Muthular Pablo Passero Fernanda Bálsamo Virginia Jewtuchowicz Valeria Miozza María Isabel Brusca Cristina Pérez 《Revista iberoamericana de micología》2019,36(3):115-119
BackgroundCandida albicans is a microorganism frequently involved in several infections; the patient's oral cavity, caries niches or periodontal disease can sometimes be the reservoir.. The fungal resistance to the available treatments, among other reasons, has led to the search for new antifungal alternatives.AimsTo carry out a comparative study of the in vitro effects of diethylstilboestrol (DES) and fluconazole (FLZ) on the growth of clinical strains of C. albicans.MethodsSeven strains of C. albicans were used: a) one FLZ-sensitive culture collection strain, ATCC 90028 (ATCC); b) four oral isolates from four oncological patients with periodontal disease (period 8, 9, 10, and 11); and c) two oral isolates from an AIDS patient with oropharyngeal candidiasis: one FLZ- sensitive (2-76), and another FLZ- resistant (12-99). The MIC was evaluated by standard spectrophotometric techniques using the CLSI (M27-A3) guidelines. The inhibitory concentration 50% (IC50) was calculated using functional analysis with the Graph Pad software.ResultsDES inhibited the growth of all C. albicans strains, whether sensitive or resistant to FLZ. Experimental data fitted non-linear functions of inhibitor concentration versus response. Minimum inhibitory concentrations (MIC) for DES and FLZ were as follows: 28.18 µg/ml and 4.90 µg/ml (ATCC); 17.16 µg/ml and 3.14 µg/ml (period); 27.64 µg/ml and 4.22 µg/ml (2-76); 6.16 µg/ml and 438.19 µg/ml (12-99), respectively.ConclusionsDES showed antifungal activity on all clinical C. albicans strains isolated from patients with dental and medical diseases. It showed the highest potency on the FLZ-resistant isolate. 相似文献
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70.
Alcorta Jaime Vergara-Barros Pablo Antonaru Laura A. Alcamán-Arias María E. Nürnberg Dennis J. Díez Beatriz 《Extremophiles : life under extreme conditions》2019,23(6):635-647
Extremophiles - The true-branching cyanobacterium Fischerella thermalis (also known as Mastigocladus laminosus) is widely distributed in hot springs around the world. Morphologically, it has been... 相似文献