60 research outputs found

    Assessing the effectiveness of the Ramsar Convention in preserving wintering waterbirds in the Mediterranean

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    lthough biological conservation is based on international agreements, its effectiveness depends on how countries implement such recommendations as effective conservation tools. The Ramsar Convention is the oldest international treaty for wetland and waterbird conservation, establishing the world's largest network of protected areas. However, since it does not constitute any binding measure, its effectiveness in protecting wintering waterbird populations at an international scale has been questioned. Here, we use long-term (1991–2012) count data to assess the effectiveness of the Ramsar Convention in the Mediterranean Basin. We compared abundance and temporal trends of 114 waterbird species between 251 Ramsar wetlands and 3486 non-Ramsar wetlands. We found that the Ramsar network is critical for wintering waterbirds, concentrating nearly half of all waterbirds counted in the Mediterranean Basin in only 7% of monitored wetlands. Waterbird trends followed a northwestsoutheast gradient, with a population decrease in the East. A significant and positive Ramsar effect on population trends was only found for the species of higher conservation concern in the Maghreb, particularly when a management plan was implemented. The Ramsar Convention was previously used on very important wetlands for waterbirds in Southern Europe, but is now an underused conservation tool. Our study suggests weaknesses in the use of Ramsar as an effective conservation tool in most of the Mediterranean Basin. However, the Ramsar Convention effectiveness to enhance waterbird populations in the Maghreb should encourage strengthening the Ramsar Convention. It should be done particularly in countries with limited environmental agreements and by systematic implementation of management plans. Conservation measures International conventions Protected areas Protection status Monitoring WetlandsacceptedVersio

    Lipid and Lipoprotein Profiles in Youth With and Without Type 1 Diabetes: The SEARCH for Diabetes in Youth Case-Control Study

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    OBJECTIVE—The purpose of this study was to compare the lipid profile and the prevalence of lipid abnormalities in youth with and without type 1 diabetes and explore the role of glycemic control on the hypothesized altered lipid profile in youth with type 1 diabetes

    Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming

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    Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993-2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming.Peer reviewe

    Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming

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    Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993-2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming

    Antimicrobial Evaluation of Some Styryl Ketone Derivatives and Related Thiol Adducts

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    WOS: A1994NF27000019PubMed ID: 8046611Acyclic alpha,beta-unsaturated ketones were synthesized and treated with either 2-mercaptoethanol or cystenamine hydrochloride under the simulated physiological conditions. The thiol group of these model biological nucleophiles underwent Michael type addition to the activated double bond. The incubation of the bis-Mannich base of 3-benzylidene-2,4-pentanedione with 2-mercaptoethanol, surprisingly, gave rise to the formation of 5[(2-hydroxyethyl)thio]-1-phenyl-1-penten-3-one (8) in low yield. Evaluation of the compounds versus Grampositive and Gram-negative bacteria and also a type of fungus indicated that the conjugated ketones and their adducts, except the bis-Mannich base, have antimicrobial activity at 10 mu g/mL. The Mannich base, 3, showed antibacterial property against only Escherichia coli at 1000 mu g/mL in spite of containing a bioactive styryl ketone structure and having deamination ability. However, the thiol adducts, which do not contain any alpha,beta-unsaturated ketone function, exhibited similar antimicrobial potency to the conjugated ketone derivatives, possibly due to the exchange reaction with enzymes or coenzymes in the microorganisms

    In the Search For New Anticancer Drugs .28. Synthesis and Evaluation of Highly-Active Aminoxyl Labeled Amino-Acid Derivatives Containing the [N'-(2-Chloroethyl)-N'-Nitrosoamino]Carbonyl Group

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    WOS: A1994NX39000014PubMed ID: 7965680The aminoxyl (nitroxyl) labeled (2-chloroethyl)nitrosocarbamoyl (CNC) derivatives of amino acids, i.e., N-[[N'-(2-chloroethyl)N'-nitrosoamino] carbonyl]-A-(1-oxy-2,2,6,6-tetramethylpiperidin-4-yl)amides, A = glycyl (10a), A = L-alanyl (10b), A = L-valyl (10c), A = L-phenylalanyl (10d), were synthesized and evaluated in vitro for their anticancer activities against the murine lymphocytic leukemia P388. Compounds 10a-d possessed activities ranging from 242 to 456% increase in life span (%ILS). All CDF1 male mice treated with the highly active compounds 10b and 10c at 12 mg/kg/day for 9 days were alive after 30 days. Compounds 10a-d were then tested in vivo against the murine lymphoid leukemia L1210. Compounds 10a-d exhibited, on day 60, a %ILS of 496, 663, 663, and 581, respectively. All CDF1 male mice treated with the highly active compounds 10b and 10c at 12 mg/kg/day for 9 days were alive after 60 days. The lipophilicities of compounds 10a-d were determined using the UV method. The %ILS parameters obtained against the P388 and L1210 tumor lines were correlated with the corresponding lipophilicities, and a trend was generally observed toward an increase in cytotoxicity with a concomitant decrease in hydrophobicity

    Antimicrobial evaluation of some styryl ketone derivatives and related thiol adducts

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    PubMed ID: 8046611Acyclic ?,ß-unsaturated ketones were synthesized and treated with either 2-mercaptoethanol or cystenamine hydrochloride under the simulated physiological conditions. The thiol group of these model biological nucleophiles underwent Michael type addition to the activated double bond. The incubation of the bis-Mannich base of 3-benzylidene-2, 4-pentanedione with 2-mercaptoethanol, surprisingly, gave rise to the formation of 5- [(2-hydroxyethyl)thio]-1-phenyl-1-penten-3-one (8) in low yield. Evaluation of the compounds versus Gram-positive and Gram-negative bacteria and also a type of fungus indicated that the conjugated ketones and their adducts, except the bis-Mannich base, have antimicrobial activity at 10 µg/mL. The Mannich base, 3, showed antibacterial property against only Escherichia coli at 1000 µ/mL in spite of containing a bioactive styryl ketone structure and having deamination ability. However, the thiol adducts, which do not contain any ?,ß-unsaturated ketone function, exhibited similar antimicrobial potency to the conjugated ketone derivatives, possibly due to the exchange reaction with enzymes or coenzymes in the microorganisms. Copyright © 1994 Wiley-Liss, Inc., A Wiley Compan
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