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61.
Leandro Nolé Eduardo Michael Maia Mincarone Flávia Lucena-Frédou Júlia Rodrigues Martins Gabriel Vinícius Felix Afonso Bárbara Teixeira Villarins Thierry Frédou Alex Souza Lira Arnaud Bertrand 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):845-848
Length-weight relationship parameters were calculated for twelve mesopelagic fish species from the western Tropical Atlantic: Diretmus argenteus, Melamphaes polylepis, Bolinichthys distofax, Diaphus lucidus, Diaphus splendidus, Electrona risso, Hygophum taaningi, Taaningichthys bathyphilus, Melanolagus bericoides, Winteria telescopa, Diplophos taenia, Astronesthes similus. Data was collected off northeastern Brazil from April 9th to May 6th, 2017. Hauls were conducted during day and night at 47 stations by using a micronekton trawl (body mesh: 40 mm, cod-end mesh: 10 mm) from 10 to 1,113 m depth. The material was fixed in a 4% formalin solution for 1 month and then preserved in a 70% alcohol solution for proximally 6 months before processing for length (nearest 0.1 cm of standard length) and weight (nearest 0.01 g of total weight). A new maximum standard length for Winteria telescopa is also provided. 相似文献
62.
Ding Zhang Julie M. van der Hoop Victor Petrov Julie Rocho-Levine Michael J. Moore K. Alex Shorter 《Marine Mammal Science》2020,36(1):136-157
Drag force acting on swimming marine mammals is difficult to measure directly. Researchers often use simple modeling and kinematic measurements from animals, or computational fluid dynamics (CFD) simulations to estimate drag. However, studies that compare these methods are lacking. Here, computational simulation and physical experiments were used to estimate drag forces on gliding bottlenose dolphins (Tursiops truncatus). To facilitate comparison, variable drag loading (no-tag, tag, tag + 4, tag + 8) was used to increase force in both simulations and experiments. During the experiments, two dolphins were trained to perform controlled glides with variable loading. CFD simulations of dolphin/tag geometry in steady flow (1–6 m/s) were used to model drag forces. We expect both techniques will capture relative changes created by experimental conditions, but absolute forces predicted by the methods will differ. CFD estimates were within a calculated 90% confidence interval of the experimental results for all but the tag condition. Relative drag increase predicted by the simulation vs. experiment, respectively, differed by between 21% and 31%: tag, 4% vs. 33%; tag + 4, 47% vs. 68%; and tag + 8, 108% vs. 77%. The results from this work provide a direct comparison of computational and experimental estimates of drag, and provide a framework to quantify uncertainty. 相似文献
63.
Jenny Landberg Naia Risager Wright Tune Wulff Markus J. Herrgård Alex Toftgaard Nielsen 《Biotechnology and bioengineering》2020,117(12):3835-3848
Growth decoupling can be used to optimize the production of biochemicals and proteins in cell factories. Inhibition of excess biomass formation allows for carbon to be utilized efficiently for product formation instead of growth, resulting in increased product yields and titers. Here, we used CRISPR interference to increase the production of a single-domain antibody (sdAb) by inhibiting growth during production. First, we screened 21 sgRNA targets in the purine and pyrimidine biosynthesis pathways and found that the repression of 11 pathway genes led to the increased green fluorescent protein production and decreased growth. The sgRNA targets pyrF, pyrG, and cmk were selected and further used to improve the production of two versions of an expression-optimized sdAb. Proteomics analysis of the sdAb-producing pyrF, pyrG, and cmk growth decoupling strains showed significantly decreased RpoS levels and an increase of ribosome-associated proteins, indicating that the growth decoupling strains do not enter stationary phase and maintain their capacity for protein synthesis upon growth inhibition. Finally, sdAb production was scaled up to shake-flask fermentation where the product yield was improved 2.6-fold compared to the control strain with no sgRNA target sequence. An sdAb content of 14.6% was reached in the best-performing pyrG growth decoupling strain. 相似文献
64.
Flood Peter J. Duran Alain Barton Mark Mercado-Molina Alex E. Trexler Joel C. 《Hydrobiologia》2020,847(7):1571-1586
Hydrobiologia - Non-native species can simultaneously affect ecological structures, functions, and services of the invaded ecosystem. In this paper, we report that the study of non-native... 相似文献
65.
Emmet McCormack Katherine J. Adams Namir J. Hassan Akhil Kotian Nikolai M. Lissin Malkit Sami Maja Mujić Tereza Osdal Bjørn Tore Gjertsen Deborah Baker Alex S. Powlesland Milos Aleksic Annelise Vuidepot Olivier Morteau Deborah H. Sutton Carl H. June Michael Kalos Rebecca Ashfield Bent K. Jakobsen 《Cancer immunology, immunotherapy : CII》2013,62(4):773-785
NY-ESO-1 and LAGE-1 are cancer testis antigens with an ideal profile for tumor immunotherapy, combining up-regulation in many cancer types with highly restricted expression in normal tissues and sharing a common HLA-A*0201 epitope, 157–165. Here, we present data to describe the specificity and anti-tumor activity of a bifunctional ImmTAC, comprising a soluble, high-affinity T-cell receptor (TCR) specific for NY-ESO-1157–165 fused to an anti-CD3 scFv. This reagent, ImmTAC-NYE, is shown to kill HLA-A2, antigen-positive tumor cell lines, and freshly isolated HLA-A2- and LAGE-1-positive NSCLC cells. Employing time-domain optical imaging, we demonstrate in vivo targeting of fluorescently labelled high-affinity NYESO-specific TCRs to HLA-A2-, NY-ESO-1157–165-positive tumors in xenografted mice. In vivo ImmTAC-NYE efficacy was tested in a tumor model in which human lymphocytes were stably co-engrafted into NSG mice harboring tumor xenografts; efficacy was observed in both tumor prevention and established tumor models using a GFP fluorescence readout. Quantitative RT-PCR was used to analyze the expression of both NY-ESO-1 and LAGE-1 antigens in 15 normal tissues, 5 cancer cell lines, 10 NSCLC, and 10 ovarian cancer samples. Overall, LAGE-1 RNA was expressed at a greater frequency and at higher levels than NY-ESO-1 in the tumor samples. These data support the clinical utility of ImmTAC-NYE as an immunotherapeutic agent for a variety of cancers. 相似文献
66.
Assessment of systematic effects of methodological characteristics on candidate genetic associations
Badr Aljasir John P. A. Ioannidis Alex Yurkiewich David Moher Julian P. T. Higgins Paul Arora Julian Little 《Human genetics》2013,132(2):167-178
Candidate genetic association studies have been found to have a low replication rate in the past. Here, we aimed to assess whether aspects of reported methodological characteristics in genetic association studies may be related to the magnitude of effects observed. An observational, literature-based investigation of 511 case–control studies of genetic association studies indexed in 2007, was undertaken. Meta-regression analyses were used to assess the relationship between 23 reported methodological characteristics and the magnitude of genetic associations. The 511 studies had been conducted in 52 countries and were published in 220 journals (median impact factor 5.1). The multivariate meta-regression model of methodological characteristics plus disease category accounted for 17.2 % of the between-study variance in the magnitude of the reported genetic associations. Our findings are consistent with the view that better conducted and better reported genetic association research may lead to less inflated results. 相似文献
67.
Root Transcript Profiling of Two Rorippa Species Reveals Gene Clusters Associated with Extreme Submergence Tolerance 总被引:1,自引:0,他引:1
68.
69.
Loreto Rojas-Sobarzo Manuel Olivares Alex Brito Miriam Suazo Magdalena Araya Fernando Pizarro 《Biological trace element research》2013,153(1-3):1-4
There is a close relationship between selenium deficiency and Kaschin–Beck disease (KBD). Although the etiology of KBD is not known and selenium deficiency is not its actual cause, it is an important environmental risk factor. In particular, in the Qing-Tibet Plateau, a selenium-deficient region, the prevalence of KBD is serious and still increasing and continues to damage public health. By providing selenium to the population in appropriate amounts, and especially to children, KBD can be effectively controlled and prevented. 相似文献
70.
Sarah A. Scott Yun Xiang Thomas P. Mathews Hyekyung P. Cho David S. Myers Michelle D. Armstrong Keri A. Tallman Matthew C. O'Reilly Craig W. Lindsley H. Alex Brown 《The Journal of biological chemistry》2013,288(28):20477-20487
Phosphatidic acid (PA) is a lipid second messenger located at the intersection of several lipid metabolism and cell signaling events including membrane trafficking, survival, and proliferation. Generation of signaling PA has long been primarily attributed to the activation of phospholipase D (PLD). PLD catalyzes the hydrolysis of phosphatidylcholine into PA. A variety of both receptor-tyrosine kinase and G-protein-coupled receptor stimulations have been shown to lead to PLD activation and PA generation. This study focuses on profiling the PA pool upon P2Y6 receptor signaling manipulation to determine the major PA producing enzymes. Here we show that PLD, although highly active, is not responsible for the majority of stable PA being produced upon UDP stimulation of the P2Y6 receptor and that PA levels are tightly regulated. By following PA flux in the cell we show that PLD is involved in an initial increase in PA upon receptor stimulation; however, when PLD is blocked, the cell compensates by increasing PA production from other sources. We further delineate the P2Y6 signaling pathway showing that phospholipase Cβ3 (PLCβ3), PLCδ1, DGKζ and PLD are all downstream of receptor activation. We also show that DGKζ is a novel negative regulator of PLD activity in this system that occurs through an inhibitory mechanism with PKCα. These results further define the downstream events resulting in PA production in the P2Y6 receptor signaling pathway. 相似文献