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21.
Certification of sustainable palm oil as organised through the Round Table on Sustainable Palm Oil is based on a simplified understanding of the global palm oil value chain – according to which instructions about production practices can be directly translated from the palm oil mill to the primary producer. The reality of palm oil provision is much more complex than this as is shown in the case of Thailand. On the basis of qualitative field study in Southern Thailand this paper clarifies that intermediary stages, such as the collection of oil palm fruit bunches at the ramp, play a key role in the organisation of the chain. The fluidity and complexity of the palm oil flow at the local level complicates the promotion of sustainability through certification. Global and national stakeholders, such as processing and trading firms, non‐governmental organisations and national governments, should therefore open this black box of local dynamics to more effectively contribute to sustainability in palm oil supply. 相似文献
22.
Juana Durán Elena Pastor Amalia Grau José María Valencia 《Aquaculture Research》2012,43(12):1777-1786
The Mediterranean spider crab, Maja squinado, is depleted due to overfishing. The crab has virtually disappeared from areas where it was abundant, such as the Balearic Islands and the Catalan coast. Maja squinado, is economically and ecologically very valuable, and it is essential to obtain information on its biology and rearing conditions to attempt to repopulate the damaged stocks of the species in the Mediterranean basin. Herein, we describe the first successful rearing of M. squinado under laboratory conditions. Our results show that M. squinado is an excellent candidate for restocking using cultured juveniles. Two consecutive broods with a 1–4 day interbrood period were observed in the laboratory in wild‐caught females, the maximum observed duration of embryonic development of the egg mass being 32 days at 18.4 ± 0.9°C, and went through four different stages. The complete larval and first juvenile development was studied in laboratory cultures fed enriched Artemia metanauplius. At 19.6 ± 0.6°C, development from hatching to first crab moult took 17 days, and it comprised two zoeae stages and one megalopa stage. The survival rate at the different stages was monitored, and 7.13 ± 2.3% was achieved at the first crab instar. 相似文献
23.
Mattana Efisio Peguero Brígido Di Sacco Alice Agramonte Wilvin Encarnación Castillo Wilkin Rafael Jiménez Francisco Clase Teodoro Pritchard Hugh W. Gómez-Barreiro Pablo Castillo-Lorenzo Elena Terrero Encarnación Marianny Way Michael J. García Ricardo Ulian Tiziana 《New Forests》2020,51(4):705-721
New Forests - Native trees from the Caribbean were tested for seed desiccation responses, by adapting the “100-seed test” protocol. Ninety-seven seed lots of 91 species were collected... 相似文献
24.
Dongchen An Ernesto Lopes Pinheiro-Junior Lszl Bress Irina Gladkikh Elena Leychenko Eivind A. B. Undheim Steve Peigneur Jan Tytgat 《Marine drugs》2022,20(2)
(1) Background: G protein-coupled inward-rectifier potassium (GIRK) channels, especially neuronal GIRK1/2 channels, have been the focus of intense research interest for developing drugs against brain diseases. In this context, venom peptides that selectively activate GIRK channels can be seen as a new source for drug development. Here, we report on the identification and electrophysiological characterization of a novel activator of GIRK1/2 channels, AsKC11, found in the venom of the sea anemone Anemonia sulcata. (2) Methods: AsKC11 was purified from the sea anemone venom by reverse-phase chromatography and the sequence was identified by mass spectrometry. Using the two-electrode voltage-clamp technique, the activity of AsKC11 on GIRK1/2 channels was studied and its selectivity for other potassium channels was investigated. (3) Results: AsKC11, a Kunitz peptide found in the venom of A. sulcata, is the first peptide shown to directly activate neuronal GIRK1/2 channels independent from Gi/o protein activity, without affecting the inward-rectifier potassium channel (IRK1) and with only a minor effect on KV1.6 channels. Thus, AsKC11 is a novel activator of GIRK channels resulting in larger K+ currents because of an increased chord conductance. (4) Conclusions: These discoveries provide new insights into a novel class of GIRK activators. 相似文献
25.
Ernesto Lopes Pinheiro-Junior Rimma Kalina Irina Gladkikh Elena Leychenko Jan Tytgat Steve Peigneur 《Marine drugs》2022,20(2)
Sea anemones are a rich source of biologically active compounds. Among approximately 1100 species described so far, Heteractis crispa species, also known as sebae anemone, is native to the Indo-Pacific area. As part of its venom components, the Hcr 1b-2 peptide was first described as an ASIC1a and ASIC3 inhibitor. Using Xenopus laevis oocytes and the two-electrode voltage-clamp technique, in the present work we describe the remarkable lack of selectivity of this toxin. Besides the acid-sensing ion channels previously described, we identified 26 new targets of this peptide, comprising 14 voltage-gated potassium channels, 9 voltage-gated sodium channels, and 3 voltage-gated calcium channels. Among them, Hcr 1b-2 is the first sea anemone peptide described to interact with isoforms from the Kv7 family and T-type Cav channels. Taken together, the diversity of Hcr 1b-2 targets turns this toxin into an interesting tool to study different types of ion channels, as well as a prototype to develop new and more specific ion channel ligands. 相似文献
26.
Antonis Vlachavas Nikoleta Karaiskou Lambros Kokokiris Foteini‐Izampela Zampeta Elena Drosopoulou Alexander Triantafyllidis 《Aquaculture Research》2019,50(1):312-322
Large quantities of high protein fish meals are needed to sustain cultured species and thus the impact to marine ecosystem has been highly discussed. The aim of this study was to apply a PCR‐cloning methodology for a robust insight into the composition of commercial fish meals and feeds for farmed species of the Greek mariculture, assessing the risk posed by aquaculture to marine ecosystems but also the risk posed by commercial fish feeds to the increase in trophic level of species farmed in Greece. 89% of the sequences were identified to species level and only 11% to genus/family level. Overall, a total of 49 taxa were identified (44 fish species/taxon, five non‐fish species/taxon). Even though small pelagic fish like Engraulis sp. were the main portion, a wide range of species constituted the fish meals and feeds. Plant and animal species were also detected as an alternative protein source. Feed products employed in Greek mariculture still contain large portions of fish meals which increase the mean trophic level of farmed species causing a farming up trend. The results emphasize that such molecular methodologies are needed to certify aquafeeds allowing fish feed producers to demonstrate their commitment to sustainable aquaculture. 相似文献
27.
The present work evaluated the chemical composition of the essential oils (EO) obtained from Lippia origanoides and their DNA protective effect against bleomycin-induced genotoxicity. L. origanoides EO chemical composition was determined by gas chromatography–mass spectrometry (GC–MS). The major compounds of the L. origanoides EOs were thymol (34–58%) and carvacrol (26%). The antigenotoxic effects of the EOs, major compounds and standard compound (epigallocatechin gallate) were assayed in co-incubation procedures using the SOS chromotest in Escherichia coli. Both EOs and their major compounds protected bacterial cells against bleomycin-induced genotoxicity indicating that these two compounds were principally responsible for the antigenotoxicity detected in the oils. Thymol and carvacrol antigenotoxicity was lower than those observed with epigallocatechin gallate. The results were discussed in relation to the chemopreventive potential of L. origanoides EOs and their major components, carvacrol and thymol. 相似文献
28.
David J Everest Susan Waterhouse Tina Kelly Elena Velo-Rego Maurice J Sauer 《Journal of veterinary diagnostic investigation》2007,19(5):552-557
Management of prion diseases in livestock would benefit greatly from availability of a validated blood test. A promising immunocapillary electrophoresis technique (also known as capillary electrophoresis fluoroimmunoassay) to detect abnormal prion protein in blood from live sheep is evaluated here. Capillary electrophoresis fluoroimmunoassay was applied to analysis of extracted blood from scrapie-exposed sheep (n = 87; 347 samples) at various stages of incubation, and to control sheep (n = 194; 489 samples). Overall, test values for the control and test populations were not significantly different, and a similar proportion of control (7%) and test (10%) sheep were classified as positive. Over 2-3 month intervals from birth until clinical disease, test specificity and sensitivity ranged from 66.7% to 100% and 0% to 66.7%, respectively, indicating poor diagnostic performance at all stages of pathogenesis. In routine application, in its present form, the capillary electrophoresis fluoroimmunoassay procedure proved to be insufficiently robust for use as a blood test for scrapie diagnosis. 相似文献
29.
K. Elena 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(2):259-262
During the last three years, a new disease was observed in northwestern Greece on Minneola trees, hybrid of mandarin and grapefruit. On May small brown necrotic leaf spots surrounded by yellow halo areas of various sizes appeared and covered a major portion of the leaves with extension of necrosis into the veins. On young fruits small, slightly depressed black spots were the first symptoms, which later became 2–7 mm in diameter. Brown spots were observed on the leaves and fruits in several orchards in the same area, causing leaves and fruits to drop. In some orchards over 50% of the fruits were affected. From the fruit and leaf spots the typical small-spore species Alternaria alternata was isolated. Pathogenicity tests were performed by artificially inoculating fruits of Minneola, common mandarin and Clementine. The symptoms of the disease were reproduced only on fruits of Minneola hybrids by the specific strain of the fungus Alternaria alternata pv. citri. Different citrus susceptibility tests indicated that mandarins Minneola, Nova and Page were very susceptible to tested isolates while Clementine SRA and Poros Clementine were not. All lemons and lime Seedless were not susceptible. Grapefruit New Hall was not susceptible, while the Star Ruby was. Orange Lane Late, Navel Late, Oval Poros, Olinda, Navel Athos were not susceptible and only Moro showed reaction being slightly susceptible only to one isolate. 相似文献
30.
A boll rot of cotton (Gossypium hirsutum L.) was observed for the first time in Greece in August 1993 in Larissa and Volos counties, and in August and September 1995
in Trikala and Phthiotis counties. Fungi of the genusPhytophthora were isolated from diseased plants. Morphological characteristics of the pathogen were recorded on mounts made directly from
the infected tissues or after growth of the isolated fungus on corn meal agar or sterile distilled water. Colony morphology,
growth rates, features of asexual and sexual structures and maximum growth temperatures were examined. APhytophthora species new to Europe,Phytophthora boehmeriae Sawada, attacking cotton bolls, was identified. The pathogenicity of the isolates was confirmed by artificial inoculations
of detached cotton bolls. Analysis of α-esterase isozymes revealed unique banding patterns for isolates ofP. boehmeriae compared with those ofP. cactorum andP. parasitica, which arePhytophthora species with similar morphology. 相似文献