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1.
The combination of highly equipped smartphones, with the increased use of social media, has offered a wide database. Given this, citizen science can be used to record and monitor non-native fish fauna, target new samples and collaborate with monitoring occurrences in new areas. We aimed to demonstrate the efficiency of social media in citizen science as a tool to cooperate with monitoring studies of non-native species. Consequently, we determined the occurrence points of S. brasiliensis in the Iguaçu River basin, indicating sites of greatest occurrence and analyzing the impact of the invasion on the native fauna of the basin. Files and information available on the YouTube® and Facebook® media platforms were used as data, was carried out from April 2019 to April 2020. The results were 40 records, 22 videos obtained from Youtube, and seven videos and 11 photos from Facebook, the oldest record was from April 2013, while the largest number of posts was in 2016. Fish records available from online platforms can reveal the occurrence and progressive dispersion of species, in the context of biological invasions, these tools can be of great value in studies that aim to follow the progress of introduced species, contributing by helping to direct new sampling programs and corroborating the occurrence of species in new areas in conjunction with standard monitoring programs. Based on citizen science records, it was possible to update the range of occurrence of the non-native S. brasiliensis in the Iguaçu River basin, cooperating with scientific knowledge. Innovative monitoring and control measures are necessary to deal with invasive species, with citizen science proving to be competent for determining the occurrence of species and showing promise in the entire field of ichthyology.  相似文献   
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The viability of algae-based biodiesel industry depends on the selection of adequate strains in regard to profitable yields and oil quality. This work aimed to bioprospecting and screening 12 microalgae strains by applying, as selective criteria, the volumetric lipid productivity and the fatty acid profiles, used for estimating the biodiesel fuel properties. Volumetric lipid productivity varied among strains from 22.61 to 204.91 mg l?1 day?1. The highest lipid yields were observed for Chlorella (204.91 mg l?1 day1) and Botryococcus strains (112.43 and 98.00 mg l?1 day?1 for Botryococcus braunii and Botryococcus terribilis, respectively). Cluster and principal components analysis analysis applied to fatty acid methyl esters (FAME) profiles discriminated three different microalgae groups according to their potential for biodiesel production. Kirchneriella lunaris, Ankistrodesmus fusiformis, Chlamydocapsa bacillus, and Ankistrodesmus falcatus showed the highest levels of polyunsaturated FAME, which incurs in the production of biodiesels with the lowest (42.47–50.52) cetane number (CN), the highest (101.33–136.97) iodine values (IV), and the lowest oxidation stability. The higher levels of saturated FAME in the oils of Chlamydomonas sp. and Scenedesmus obliquus indicated them as source of biodiesel with higher oxidation stability, higher CN (63.63–64.94), and lower IV (27.34–35.28). The third group, except for the Trebouxyophyceae strains that appeared in isolation, are composed by microalgae that generate biodiesel of intermediate values for CN, IV, and oxidation stability, related to their levels of saturated and monosaturated lipids. Thus, in this research, FAME profiling suggested that the best approach for generating a microalgae-biodiesel of top quality is by mixing the oils of distinct cell cultures.  相似文献   
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Several specimens of Mytilus galloprovincialis, collected in the Ria of Vigo over a non-consecutive 2 yr period (1993 to 1994 and 1996 to 1997), presented a possible gonadal neoplasm, entailing morphologically abnormal germinal cells distributed throughout the follicle and invading the adjacent storage tissue. In some cases, affected cells were noted in gonoducts and in haemic sinusoids. Prevalence of this anomaly in the samples was 6%, and all affected individuals were found between April and June. During the rest of the year, individuals presented normal gonadal tissue.  相似文献   
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The present immunocytochemical study provides evidence of a previously unrecognized, rich, γ-aminobutyric acid (GABA)-ergic innervation of the pineal organ in the dogfish (Scyliorhinus canicula). In this elasmobranch, the pineal primordium is initially detected at embryonic stage 24 and grows to form a long pineal tube by stage 28. Glutamic acid decarboxylase (GAD)-immunoreactive (-ir) fibers were first observed at stage 26, and by stage 28, thin GAD-ir fibers were detectable at the base of the pineal neuroepithelium. In pre-hatchling embryos, most fibers gave rise to GAD-ir boutons that were localized in the basal region of the neuroepithelium, although a smaller number of labeled terminals ascended to the pineal lumen. A few pale GAD-ir perikarya were observed within the pineal organ of stage 29 embryos, but GAD-ir perikarya were not observed at other developing stages or in adults. In contrast, GABA immunocytochemistry revealed the presence of GABAergic perikarya and fibers in the pineal organ of late stage embryos and adults. Although high densities of GABAergic cells were observed in the paracommissural pretectum, posterior tubercle, and tegmentum of dogfish embryos (regions previously demonstrated to contain pinealopetal cells), the presence of GABA-ir perikarya in the pineal organ strongly suggests that the rich GABAergic innervation of the elasmobranch pineal organ is intrinsic. This contrasts with the central origin of GABAergic fibers in the pineal gland of some mammals. This work was supported by the Spanish Education and Science Ministry and FEDER (BXX2000-0453-C02 and BFU2004-03313/BF1), the Xunta de Galicia (PGIDT99BIO20002), and NIH/NIDCD awards R01 DC01705 and P01 DC01837 (to G.R.H.).  相似文献   
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Key message

This study identified Rht25, a new plant height locus on wheat chromosome arm 6AS, and characterized its pleiotropic effects on important agronomic traits.

Abstract

Understanding genes regulating wheat plant height is important to optimize harvest index and maximize grain yield. In modern wheat varieties grown under high-input conditions, the gibberellin-insensitive semi-dwarfing alleles Rht-B1b and Rht-D1b have been used extensively to confer lodging tolerance and improve harvest index. However, negative pleiotropic effects of these alleles (e.g., poor seedling emergence and reduced biomass) can cause yield losses in hot and dry environments. As part of current efforts to diversify the dwarfing alleles used in wheat breeding, we identified a quantitative trait locus (QHt.ucw-6AS) affecting plant height in the proximal region of chromosome arm 6AS (<?0.4 cM from the centromere). Using a large segregating population (~?2800 gametes) and extensive progeny tests (70–93 plants per recombinant family), we mapped QHt.ucw-6AS as a Mendelian locus to a 0.2 cM interval (144.0–148.3 Mb, IWGSC Ref Seq v1.0) and show that it is different from Rht18. QHt.ucw-6AS is officially designated as Rht25, with Rht25a representing the height-increasing allele and Rht25b the dwarfing allele. The average dwarfing effect of Rht25b was found to be approximately half of the effect observed for Rht-B1b and Rht-D1b, and the effect is greater in the presence of the height-increasing Rht-B1a and Rht-D1a alleles than in the presence of the dwarfing alleles. Rht25b is gibberellin-sensitive and shows significant pleiotropic effects on coleoptile length, heading date, spike length, spikelet number, spikelet density, and grain weight. Rht25 represents a new alternative dwarfing locus that should be evaluated for its potential to improve wheat yield in different environments.
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Different yields, biopotency, and in vivo pharmacokinetics are obtained for recombinant sea bass gonadoltropins depending on the production system and DNA construct, but they show specific activation of their corresponding receptors. Gonadotropins (GTHs) are glycoprotein hormones that play a major role in the regulation of gonadal functions. Recently, we succeeded in isolating the native sea bass Fsh from sea bass pituitaries, but to ensure the availability of bioactive GTHs and no cross-contamination with other related glycoproteins, recombinant sea bass GTHs were produced using two expression systems-insect and mammalian cells-and different constructs that yielded tethered or noncovalently bound dimers. Their production levels, binding specificity to their homologous cognate receptors, and bioactivity were investigated and compared. Both expression systems were successful in the generation of bioactive recombinant GTHs, but insect Sf9 cells yielded higher amounts of recombinant proteins than mammalian Chinese Hamster Ovary (CHO) stable clones. All recombinant GTHs activated their cognate receptors without cross-ligand binding and were able to stimulate sea bass gonadal steroidogenesis in vitro, although with different biopotencies. To assess their use for in vivo applications, their half-life in sea bass plasma was evaluated. Sf9-GTHs had a lower in vivo stability compared with CHO-GTHs due to their rapid clearance from the blood circulation. Cell-dependent glycosylation could be contributing to the final in vivo stability and biopotency of these recombinant glycoproteins. In conclusion, both insect and mammalian expression systems produced bioactive sea bass recombinant gonadotropins, although with particular features useful for different proposes (e.g., antibody production or in vivo studies, respectively).  相似文献   
10.
A mapping population of 186 recombinant inbred lines developed from a cross between UC1110, an adapted California spring wheat, and PI610750, a synthetic derivative from CIMMYT’s Wide Cross Program, was evaluated for its response to current California races of stripe rust (Puccinia striiformis f. sp. tritici) in replicated field trials over four seasons (2007–2010) in the northern Sacramento Valley. A genetic map was constructed consisting of 1,494 polymorphic probes (SSRs, DArTs, and ESTs) mapped to 558 unique loci, and QTL analysis revealed the presence of four stripe rust resistance QTL segregating in this population, two from UC1110 (on chromosomes 3BS and 2BS) and two from PI610750 (5AL and 2AS). The two QTL of largest effects (on 3BS and 5AL) were validated in independent populations and their intervals narrowed to 2.5 and 5.3 cM, respectively. The 3BS QTL was shown, by allelism test and genotype, to carry a gene different from the Yr30/Sr2 complex. Mapped position also suggests that the 3BS QTL is associated with a gene different from either Yrns-B1 or YrRub, two stripe rust resistance genes mapped to this region in other studies. The 5AL QTL carries a previously unreported partial stripe rust resistance gene, designated here as Yr48. This paper discusses the individual contributions to resistance of these four QTL, their epistatic interactions, and their potential in durable resistance breeding strategies based on combinations of partial resistance genes.  相似文献   
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