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141.
Morgane Brosse Hugo Bucher Aymon Baud sa M. Frisk Nicolas Goudemand Hans Hagdorn Alexander Nützel David Ware Michael Hautmann 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2019,52(2):165-187
A new Early Triassic marine fauna is described from an exotic block (olistolith) from the Ad Daffah conglomerate in eastern Oman (Batain), which provides new insights into the ecology and diversity during the early aftermath of the Permian–Triassic Boundary mass extinction. Based on conodont quantitative biochronology, we assign a middle Griesbachian age to the upper part of this boulder. It was derived from an offshore seamount and yielded both nektonic and benthic faunas, including conodonts, ammonoids, gastropods and crinoid ossicles in mass abundance. This demonstrates that despite the stratigraphically near extinction at the Permian–Triassic Boundary, Crinoidea produced enough biomass to form crinoidal limestone as early as middle Griesbachian time. Baudicrinus, previously placed in Dadocrinidae, is now placed in Holocrinidae; therefore, Dadocrinidae are absent in the Early Triassic, and Holocrinidae remains the most basal crown‐group articulates, originating during the middle Griesbachian in the Tethyan Realm. Abundant gastropods assigned to Naticopsis reached a shell size larger than 20 mm and provide another example against any generalized Lilliput effect during the Griesbachian. Whereas the benthic biomass was as high as to allow the resumption of small carbonate factories, the taxonomic diversity of the benthos remained low compared to post‐Early Triassic times. This slow benthic taxonomic recovery is here attributed to low competition within impoverished post‐extinction faunas. 相似文献
142.
Mara C. Almeida Hugo J. Message Paulo V. Sanches Dirceu Baumgartner Robie A. Bombardelli Gilmar Baumgartner Langeani Francisco 《Journal of fish biology》2019,94(2):320-324
This study investigated the morphology, morphometric and meristic characters of 117 larval Pimelodus britskii showing early development of head, eye, barbel and snout. Body and mouth pigmentation increased throughout development; the mouth was ventrally situated in the yolk-sac stage, becoming subterminal afterwards, and an embryonic fin was visible in all four stages observed. Post-flexion larval P. bristskii are distinguished from larval P. ortmanni by having 47–50 myomeres (v. 36). 相似文献
143.
144.
Adam A. Prez Que Chen Hugo Pineda Hernndez Filipe Branco dos Santos Klaas J. Hellingwerf 《Physiologia plantarum》2019,166(1):413-427
A sustainable society will have to largely refrain from the use of fossil carbon deposits. In such a regime, renewable electricity can be harvested as a primary source of energy. However, as for the synthesis of carbon‐based materials from bulk chemicals, an alternative is required. A sustainable approach towards this is the synthesis of commodity chemicals from CO2, water and sunlight. Multiple paths to achieve this have been designed and tested in the domains of chemistry and biology. In the latter, the use of both chemotrophic and phototrophic organisms has been advocated. ‘Direct conversion’ of CO2 and H2O, catalyzed by an oxyphototroph, has excellent prospects to become the most economically competitive of these transformations, because of the relative ease of scale‐up of this process. Significantly, for a wide range of energy and commodity products, a proof of principle via engineering of the corresponding production organism has been provided. In the optimization of a cyanobacterial production organism, a wide range of aspects has to be addressed. Of these, here we will put our focus on: (1) optimizing the (carbon) flux to the desired product; (2) increasing the genetic stability of the producing organism and (3) maximizing its energy conversion efficiency. Significant advances have been made on all these three aspects during the past 2 years and these will be discussed: (1) increasing the carbon partitioning to >50%; (2) aligning product formation with the growth of the cells and (3) expanding the photosynthetically active radiation region for oxygenic photosynthesis. 相似文献
145.
146.
Madina Mst Hur Rahman Md Saifur Zheng Huanquan Germain Hugo 《Plant molecular biology》2019,101(4-5):343-354
Plant Molecular Biology - Short review focussing on the role and targeting of vacuolar substructure in plant immunity and pathogenesis. Plants lack specialized immune cells, therefore each plant... 相似文献
147.
Photosynthesis Research - A recent publication (Esteban in New Phytol 217:341–342, 2018) describes how the use and citation of the assay of chlorophylls a and b extracted in aqueous 80%... 相似文献
148.
de Oliveira Hellen Oliveira de Castro Gledson Luiz Salgado Correa Lorena Oliveira Silvestre Walter Vellasco Duarte do Nascimento Sidney Vasconcelos da Silva Valadares Rafael Borges de Oliveira Guilherme Corrêa Santos Rodolfo Inacio Nunes Festucci-Buselli Reginaldo Alves Pinheiro Hugo Alves 《Photosynthesis research》2019,140(2):189-205
Photosynthesis Research - This study examined whether drought sensitivity in açaí (Euterpe oleracea Mart.) is associated with reductions in photosynthesis and increasing oxidative stress... 相似文献
149.
ngel A. del Río‐Chvez Hugo A. García‐Gutirrez Luisa U. Romn‐Marín Lidia Beiza‐Granados Carlos M. Cerda‐García‐Rojas Pedro Joseph‐Nathan Juan D. Hernndez‐Hernndez 《Chirality》2019,31(11):934-946
The epimeric diterpenes (+)‐(1S,3E,7E,11S,12S)‐verticilla‐3,7‐dien‐12‐ol ( 1 ), isolated from Bursera suntui, and (+)‐(1S,3E,7E,11S,12R)‐verticilla‐3,7‐dien‐12‐ol ( 2 ), isolated from Bursera kerberi, gave the same Wagner‐Meerwein rearrangement product (?)‐(1E,4Z,8Z,11S,12R)‐phomacta‐1,(15)4,8‐triene ( 3 ). The Et2O:BF3‐induced transformations evidence that verticillenes and phomactanes, both containing the bicyclo[9.3.1]pentadecane skeleton, are biogenetically related through the verticillen‐12‐yl cation ( A + ), which also is a key intermediate in the biosynthetic pathways to generate antitumor taxanes. Molecular modeling using the Monte Carlo protocol, followed by density functional theory (DFT) geometry optimization employing the hybrid functionals B3LYP and B3PW91, both with the DGDZVP basis set, secured the configuration of 3 as followed from the good agreement between the calculated and experimental vibrational circular dichroism spectra. Similar DFT calculations allowed determining the absolute configuration of (+)‐(1R,4R,5R,8S,9S,11S,12R,15R)‐1,15:4,5:8,9‐triepoxyphomactane ( 9 ), which surprisingly derives from epoxidation of the second minimum energy conformer of 3 . 相似文献
150.
Rodrigo Fortes-Silva Fabiola De Oliveira Paes Leme Túlio Pacheco Boaventura Helena Corrêa Pinto De Mendonça Jane Prado Leite Moreira Pedro Hugo Henriques Cunha 《Chronobiology international》2019,36(2):276-287
The aim of this study was to investigate the daily rhythms of hematological, biochemical and enzymatic parameters of the blood of a nocturnal model of fish (Lophiosilurus alexandri) bred in the laboratory (F1). Thirty-six juveniles were stocked in six tanks of a recirculation aquaculture system for 20 days. The fish were exposed to a light:dark cycle of 12:12 h and were fed 1% of biomass twice a day with commercial diet. The daily rhythms of hematological, biochemical and enzymatic parameters were then measured at six sampling times “zeitgeber time = ZT” at four-hour intervals under light:dark 12:12 h (lights on = ZT0, at 8.00 a.m). No differences were observed to alkaline phosphatase, glucose, cortisol, aspartate aminotransferase, superoxide dismutase, total protein and hematocrit (p > 0.05). However, white blood cell count, Lymphocytes (LYN), Neutrophils (NEU), Eosinophil and Neutrophils to Lymphocytes ratio were significant different between sample times (p < 0.05). Also, a significant difference in alanine transaminase was observed, with a peak of production at nighttime. In contrast, glutathione peroxidase peaked at 8:00. Uric acid, magnesium and Calcium (Ca++) showed statistically significant differences (p < 0.05). A significant difference was observed (p < 0.05), with a peak of albumin at 08:00 and triglycerides at 12:00, while cholesterol was low (p < 0.05) at 08:00 and higher from 12:00 to 04:00. Cosinor analysis revealed also rhythmicity to SOD, UA, Mg and Ca++, ALB and CHO (p < 0.05). In conclusion, the time of day must be considered a key factor when using blood parameters as biomarkers for disease, health and welfare in the L. alexandri aquaculture. 相似文献