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Alexandrium taylori Balech is a phototrophic marine dinoflagellate. It produced recurrent blooms during the summer months (July and August) of 1994 to 1997 in La Fosca beach (NW Mediterranean). In addition to a motile vegetative form, A. taylori had two benthic forms: temporary cysts and resting cysts. Temporary cysts were a temporally quiescent stage produced from the ecdysis of the vegetative cell in both natural populations and laboratory cultures. Temporary cysts may divide to form motile cells. Resting cysts had a thicker wall than the temporary cysts and had a red accumulation body. Gametes and planozygotes were also observed in laboratory cultures. Alexandrium taylori showed in situ diurnal vertical migration with an increase of vegetative cells in the water column in the morning through midday, with concentrations peaking in the afternoon followed by lower levels at night. Most vegetative cells lost their thecae and flagella, and with them their motility, turning into temporary cysts that settled in the early evening. The number of temporary cysts in the water column rose in the evening and at night. The temporary cysts gave rise to motile cells the following morning. Synthesis of DNA occurred in vegetative cells at night, and a preferential period of cell division occurred at sunrise. The estimated division rate in the field was 0.4–0.5 vegetative cells·day−1 . Temporary cysts had twice the DNA of a G1 vegetative cell. The minimum in situ division rate of the temporary cysts was 0.14 day−1 . The role of the resting and temporary cyst population in the annual recurrence and maintenance of the A. taylori bloom is discussed. 相似文献
146.
Francisco Javier Blancas Mercedes González Macarena Lozano-Oyola Fátima Pérez 《Ecological Indicators》2010,10(2):484-492
This paper introduces an indicator system to evaluate sustainability in established coastal tourism destinations, applying the recommendations and definitions of the World Tourism Organization (WTO). We also develop a new synthetic indicator to simplify the measurement of sustainability and facilitate the comparative analysis of destination ranking. This measurement was obtained by applying a procedure to reduce the number of subjective decisions made by the analyst, using a novel two-stage aggregation methodology based on principal component analysis and on the distance to a reference point. The synthetic indicator obtained was applied to Spanish coastal destinations, and the results serve as a guideline for tourism planning. The conclusions of this research can be extrapolated to the study of other tourism destinations. 相似文献
147.
Xabier Rodríguez‐Martínez Semih Sevim Xiaofeng Xu Carlos Franco Paula Pamies‐Puig Laura Crcoles‐Guija Romen Rodriguez‐Trujillo Francisco Javier del Campo David Rodriguez San Miguel Andrew J. deMello Salvador Pan David B. Amabilino Olle Ingans Josep Puigmartí‐Luis Mariano Campoy‐Quiles 《Liver Transplantation》2020,10(33)
Microfluidic technologies are highly adept at generating controllable compositional gradients in fluids, a feature that has accelerated the understanding of the importance of chemical gradients in biological processes. That said, the development of versatile methods to generate controllable compositional gradients in the solid‐state has been far more elusive. The ability to produce such gradients would provide access to extensive compositional libraries, thus enabling the high‐throughput exploration of the parametric landscape of functional solids and devices in a resource‐, time‐, and cost‐efficient manner. Herein, the synergic integration of microfluidic technologies is reported with blade coating to enable the controlled formation of compositional lateral gradients in solution. Subsequently, the transformation of liquid‐based compositional gradients into solid‐state thin films using this method is demonstrated. To demonstrate efficacy of the approach, microfluidic‐assisted blade coating is used to optimize blending ratios in organic solar cells. Importantly, this novel technology can be easily extended to other solution processable systems that require the formation of solid‐state compositional lateral gradients. 相似文献
148.
Nader Morshed William T Ralvenius Alexi Nott L Ashley Watson Felicia H Rodriguez Leyla A Akay Brian A Joughin PingChieh Pao Jay Penney Lauren LaRocque Diego Mastroeni LiHuei Tsai Forest M White 《Molecular systems biology》2020,16(12)
Alzheimer’s disease (AD) is characterized by the appearance of amyloid‐β plaques, neurofibrillary tangles, and inflammation in brain regions involved in memory. Using mass spectrometry, we have quantified the phosphoproteome of the CK‐p25, 5XFAD, and Tau P301S mouse models of neurodegeneration. We identified a shared response involving Siglec‐F which was upregulated on a subset of reactive microglia. The human paralog Siglec‐8 was also upregulated on microglia in AD. Siglec‐F and Siglec‐8 were upregulated following microglial activation with interferon gamma (IFNγ) in BV‐2 cell line and human stem cell‐derived microglia models. Siglec‐F overexpression activates an endocytic and pyroptotic inflammatory response in BV‐2 cells, dependent on its sialic acid substrates and immunoreceptor tyrosine‐based inhibition motif (ITIM) phosphorylation sites. Related human Siglecs induced a similar response in BV‐2 cells. Collectively, our results point to an important role for mouse Siglec‐F and human Siglec‐8 in regulating microglial activation during neurodegeneration. 相似文献
149.
Vélez Debora E. Mestre-Cordero Victoria E. Hermann Romina Perego Juliana Harriet Sofia Fernandez-Pazos María de las Mercedes Mourglia Julieta Marina-Prendes M. Gabriela 《Journal of physiology and biochemistry》2020,76(1):85-98
Journal of Physiology and Biochemistry - The cardioprotective activity of rosuvastatin (R) is yet to be known. The objective of this study was to research whether R perfusion before global ischemia... 相似文献
150.
Trace Akankunda Hien To Carlos Rodriguez Lopez Remko Leijs Katja Hogendoorn 《Molecular ecology resources》2020,20(3):692-705
For molecular insect identification, amplicon sequencing methods are recommended because they offer a cost‐effective approach for targeting small sets of informative genes from multiple samples. In this context, high‐throughput multilocus amplicon sequencing has been achieved using the MiSeq Illumina sequencing platform. However, this approach generates short gene fragments of <500 bp, which then have to be overlapped using bioinformatics to achieve longer sequence lengths. This increases the risk of generating chimeric sequences or leads to the formation of incomplete loci. Here, we propose a modified nested amplicon sequencing method for targeting multiple loci from pinned insect specimens using the MiSeq Illumina platform. The modification exists in using a three‐step nested PCR approach targeting near full‐length loci in the initial PCR and subsequently amplifying short fragments of between 300 and 350 bp for high‐throughput sequencing using Illumina chemistry. Using this method, we generated 407 sequences of three loci from 86% of all the specimens sequenced. Out of 103 pinned bee specimens of replicated species, 71% passed the 95% sequence similarity threshold between species replicates. This method worked best for pinned specimens aged between 0 and 5 years, with a limit of 10 years for pinned and 14 years for ethanol‐preserved specimens. Hence, our method overcomes some of the challenges of amplicon sequencing using short read next generation sequencing and improves the possibility of creating high‐quality multilocus barcodes from insect collections. 相似文献