45 research outputs found
Response of the Diatom Phaeodactylum tricornutum to Photooxidative Stress Resulting from High Light Exposure
The response of microalgae to photooxidative stress resulting from high light exposure is a well-studied phenomenon. However, direct analyses of photosystem II (PSII) D1 protein (the main target of photoinhibition) in diatoms are scarce. In this study, the response of the diatom model species Phaeodactylum tricornutum to short-term exposure to high light was examined and the levels of D1 protein determined immunochemically. Low light (LL) acclimated cells (40 ”mol photons mâ2 sâ1) subjected to high light (HL, 1,250 ”mol photons mâ2 sâ1) showed rapid induction of non-photochemical quenching (NPQ) and ca. 20-fold increase in diatoxanthin (DT) concentration. This resulted from the conversion of diadinoxanthin (DD) to DT through the activation of the DD-cycle. D1 protein levels under LL decreased about 30% after 1 h of the addition of lincomycin (LINC), a chloroplast protein synthesis inhibitor, showing significant D1 degradation and repair under low irradiance. Exposure to HL lead to a 3.2-fold increase in D1 degradation rate, whereas average D1 repair rate was 1.3-x higher under HL than LL, leading to decreased levels of D1 protein under HL. There were significant effects of both HL and LINC on P. tricornutum maximum quantum yield of PSII (Fv/Fm), showing a reduction of active PSII reaction centres. Partial recovery of Fv/Fm in the dark demonstrates the photosynthetic resilience of this diatom to changes in the light regime. P. tricornutum showed high allocation of total protein to D1 and an active D1-repair cycle to limit photoinhibition
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009aâb; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Can data collected in the Citizen Science project EduMar be used to monitor coastal marine biodiversity in Portugal?
In a climate change scenario, it is important to aware society for the need to protect marine species biodiversity and to ensure its sustainability. Therefore, the project EduMar/EduSea (Educate for the Sea) is being developed in Portugal aiming to educate students (elementary and middle school) for the preservation of the sea and its resources through citizen science. More than 300 students are participating in a set of interdisciplinary science activities focusing on learning the causes and consequences of climate change in ecosystems of the intertidal rocky shores and acquiring skills to identify and report on site a set of bio-indicator and common rocky shores species. At Avencas Beach, Portugal, using the iNaturalist app, students are mapping those species, gathering data to help researchers better monitoring the coastal marine biodiversity and understanding how climate change may affect that biodiversity. We will present data collected by these students analysing its quality for research purposes. We will also share our experience with such young citizen scientists and the best practices learned for future design of similar projects.info:eu-repo/semantics/publishedVersio
Palaemon longirostris (Decapoda, Caridea) Is an Alien Species in the Russian Sector of the Black Sea
Contribution of Spartina maritima to the reduction of eutrophication in estuarine systems
http://www.sciencedirect.com/science/article/B6VB5-4T4WM2P-1/2/39c53246a441c97ea5fb560b5d7dd93
Crescimento de Aegla manuinflata (Decapoda, Anomura, Aeglidae) em ambiente natural
O presente trabalho teve como objetivo avaliar o crescimento de Aegla manuinflata Bond-Buckup & Santos, 2009 em ambiente natural. Para isso foram realizadas coletas mensais de abril de 2006 a maio de 2007 no arroio Passo Taquara, no municĂpio de SĂŁo Pedro do Sul, Rio Grande do Sul, Brasil. Os organismos foram coletados utilizando armadilhas plĂĄsticas e puçå. Os espĂ©cimes foram sexados e tiveram mensurado o comprimento do cefalotĂłrax (CC), em seguida foram devolvidos ao cĂłrrego. O crescimento foi avaliado utilizando o modelo de von Bertalanffy. As curvas de crescimento do cefalotĂłrax, estimadas para machos e fĂȘmeas, sĂŁo descritas pelas seguintes equaçÔes Ct = 28,00 [1 - e-0,0047(t+10,63)] e Ct = 25,16 [1 - e-0,0051(t+17,65)], respectivamente. Os machos atingem tamanhos maiores que as fĂȘmeas. A longevidade foi estimada em trĂȘs anos para os machos e dois anos e meio para as fĂȘmeas