Growth and development of maize: accumulation of grain dry matter

 O objetivo deste trabalho foi estudar o efeito de diferentes épocas de plantio na taxa e na duração do período de enchimento dos grãos, e de que modo esses fatores determinam o peso final dos grãos de híbridos do milho (Zea mays L.). Três experimentos foram instalados no campo, nos anos de 1994-1995 a 1996-1997, com os híbridos comerciais C-901, XL-560 e XL-678, em 1994/95, e os híbridos C-901, XL-212 e XL-370, nos outros anos. Os tratamentos consistiram em diferentes datas de plantio de setembro a dezembro, em 1994/95, e de agosto a dezembro, em 1995/96 e 1996/97. A taxa efetiva do enchimento dos grãos foi diretamente dependente da temperatura média do ar, tendo sido maior nos plantios mais precoces, e resultando em grãos mais pesados do que os obtidos em plantios mais tardios. Nos plantios mais tardios, a menor temperatura do ar durante o período efetivo do enchimento dos grãos propiciou menor taxa de enchimento dos grãos, tornando-os mais leves. Conclui-se que o principal fator limitante do rendimento de grãos nesses plantios é a fonte produtora de fotoassimilados, e não a capacidade dos grãos em acumulá-los.The objective of this work was to study the effect of different sowing dates on the rate and duration of the grain filling and how such factors determine the final grain weight of a number of maize (Zea mays L.) hybrids. Three experiments were carried out under field conditions in the years 1994/95 to 1996/97, using the commercial hybrids C-901, XL-560, and XL-678 in 1994/95 and the hybrids C-901, XL-212, and XL-370 in the remaining years. The treatments consisted of sowing dates from September to December, in 1994/95, and from August to December, in 1995/96 and 1996/97. The effective grain filling rate depended directly on the mean air temperature and it was higher in earlier plantings, resulting in heavier grains, as compared to the grains obtained in the later sowings. In the later sowing dates a lower air temperature during the effective grain filling period favors a lower grain filling rate, resulting in lighter grains. In such sowing dates it is concluded that the main factor limiting yield seems to be the source of assimilate supply instead of the grain accumulation capacity

[18F]DCFPyL PET/CT versus [18F]fluoromethylcholine PET/CT in Biochemical Recurrence of Prostate Cancer (PYTHON): a prospective, open label, cross-over, comparative study

Abstract Purpose Primary objective was to compare the per-patient detection rates (DR) of [ 18 F]DCFPyL versus [ 18 F]fluoromethylcholine positron emission tomography/computed tomography (PET/CT), in patients with first prostate cancer (PCa) biochemical recurrence (BCR). Secondary endpoints included safety and impact on patient management (PM). Methods This was a prospective, open label, cross-over, comparative study with randomized treatment administration of [ 18 F]DCFPyL (investigational medicinal product) or [ 18 F]fluoromethylcholine (comparator). Men with rising prostate-specific antigen (PSA) after initial curative therapy were enrolled. [ 18 F]DCFPyL and [ 18 F]fluoromethylcholine PET/CTs were performed within a maximum time interval of 12 days. DR was defined as the percentage of positive PET/CT scans identified by 3 central imaging readers. PM was assessed by comparing the proposed pre-PET/CT treatment with the local treatment", defined after considering both PET/CTs. Results A total of 205 patients with first BCR after radical prostatectomy (73%; median PSA = 0.46 ng/ml [CI 0.16;27.0]) or radiation therapy (27%; median PSA = 4.23 ng/ml [CI 1.4;98.6]) underwent [ 18 F]DCFPyL- and/or [ 18 F]fluoromethylcholine -PET/CTs, between July and December 2020, at 22 European sites. 201 patients completed the study. The per-patient DR was significantly higher for [ 18 F]DCFPyL- compared to [ 18 F]fluoromethylcholine -PET/CTs (58% (117/201 patients) vs. 40% (81/201 patients), p  2.0: 50/57 (88%) vs. 39/57 (68%) for [ 18 F]DCFPyL- and [ 18 F]fluoromethylcholine -PET/CT, respectively). [ 18 F]DCFPyL PET/CT had an impact on PM in 44% (90/204) of patients versus 29% (58/202) for [ 18 F]fluoromethylcholine. Overall, no drug-related nor serious adverse events were observed. Conclusions The primary endpoint of this study was achieved, confirming a significantly higher detection rate for [ 18 F]DCFPyL compared to [ 18 F]fluoromethylcholine, in men with first BCR of PCa, across a wide PSA range. [ 18 F]DCFPyL was safe and well tolerated

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora