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Direct, manipulative experiments can yield important insights into the role of biodiversity in ecosystem function, but they are intrinsically limited when it comes to aspects of this relationship that emerge over long temporal and large spatial scales. Natural experiments with model systems can be a powerful complement to direct, manipulative experiments, especially where the processes that regulate biodiversity have no more than modest direct impacts on ecosystem function. Mangrove ecosystems on continental land masses and isolated islands offer unusual potential as natural experiments for biodiversity and ecosystem function studies, largely because sites with similar physical environments can have clear contrasts in the diversity of the dominant autotrophs. These contrasts provide a starting point for exploring the role of species diversity of higher plants in modulating biogeochemical functions (e.g. production, nutrient cycling), ecological functions (e.g. habitat for organisms in different tropic levels), and anthropogenic functions (e.g. maintenance of fisheries, management of sediments), on a range of time scales.

Synthetic procedures have been developed which lead to the 2-aza congeners 3 and several related N-oxides 4. The analogues 3 exhibited a wide range of in vitro cytotoxicity against L1210 leukemia, the human colon adenocarcinoma cell line LoVo, and the doxorubicin resistant LoVo/DX cell line. Selected analogues of 3 showed significant P388 antileukemic activity in mice with 3c exhibiting high activity. This activity was also retained in the related N-oxide 4a. These heterocyclic bioisosteric models are representative of the first anthracene-9,10-diones which display antileukemic activity comparable to mitoxantrone.

Growing international and national focus on quantitatively measuring and improving ocean health has increased the need for comprehensive, scientific, and repeated indicators to track progress towards achieving policy and societal goals. The Ocean Health Index (OHI) is one of the few indicators available for this purpose. Here we present results from five years of annual global assessment for 220 countries and territories, evaluating potential drivers and consequences of changes and presenting lessons learned about the challenges of using composite indicators to measure sustainability goals. Globally scores have shown little change, as would be expected. However, individual countries have seen notable increases or declines due in particular to improvements in the harvest and management of wild-caught fisheries, the creation of marine protected areas (MPAs), and decreases in natural product harvest. Rapid loss of sea ice and the consequent reduction of coastal protection from that sea ice was also responsible for declines in overall ocean health in many Arctic and sub-Arctic countries. The OHI performed reasonably well at predicting near-term future scores for many of the ten goals measured, but data gaps and limitations hindered these predictions for many other goals. Ultimately, all indicators face the substantial challenge of informing policy for progress toward broad goals and objectives with insufficient monitoring and assessment data. If countries and the global community hope to achieve and maintain healthy oceans, we will need to dedicate significant resources to measuring what we are trying to manage.

Some societies have sustainably managed their local marine resources for centuries using traditional methods, but we are only beginning to learn how to do it at larger scales, including globally. A broad, deep and constantly growing body of ocean knowledge has developed, adding many new concepts, perspectives, management models and analytical tools into the knowledge base in a relatively short period. Such rapid growth has created a potentially confusing mash-up of ideas, acronyms, The purpose of this paper is to assist policy makers, marine managers and those considering careers in this area by providing a short history of ocean management, its conceptual foundation, frameworks for modern management and examples of its application at different scales. Extensive literature exists to supplement the summarized information we present.We highlight the following terms as navigational markers through the 'seascape' 1 of marine management rhetoric: sustainability, ecosystem approach, ecosystem-based management, natural capital, ecosystem services, integrated ecosystem assessment, the causal framework DPSIR (Drivers, Pressures, States, Impacts, Responses) and its variants, indicators and reference points, marine area planning, marine spatial management (including decision support tools), adaptive ocean management and dynamic ocean management. We also point out the important roles of marine initiatives such as Blue Economy, the Ocean Health Index, Large Marine Ecosystems, Seascapes, Protected Areas and others. Understanding the similarities, differences, relationships and synergies among these activities increases the likelihood of achieving successful management processes or solutions. 1We use 'seascape' (lower case) to describe the panorama of concepts, acronyms, techniques, tools and regulations germane to marine management. 'Seascape' and 'Oceanscape' (upper case) signify specific programs for integrated management at large-scales.

6,9-Bis((aminoalkyl)amino)benzo(g)isoquinoline-5,10-diones.A Novel Class of Chromophore-Modified Antitumor Anthracene-9,10diones: Synthesis and Antitumor Evaluations.-In a search for analogues with optimal therapeutic efficacy, a series of aza analogues of (I) is prepared by reaction of (V) with the appropriate amines in a similar manner as described for (IIa) (isolated as hydrochloride). Mitoxantrone (I) is a known antitumor agent, accompanied by toxic side effects. Compounds (IIb) and (IIc) show in vitro activities against L1210 murine leukemia similar to (I), but all aza analogues have decreased cytotoxic potency in both the sensitive and the doxorubicin-resistant LoVo human colon adenocarcinoma cell line compared with (I). In vivo antitumor activity against P388 murine leukemia of (IIb) and (IId) is comparable and of (IIa) superior to that of (I). Therefore (IIa), which is not cardiotoxic and less leukopenic than (I), appears to be the most promising aza analogue for further clinical evaluation. -(KRAPCHO, A. P.; PETRY, M. E.; GETAHUN, Z.; LANDI, J. J. JUN.; STALLMAN, J.; POLSENBERG, J. F.; GALLAGHER, C. E.; MARESCH, M. J.; HACKER, M. P.; GIULIANI, F. C.; BEGGIOLIN, G.; PEZZONI, G.; MENTA, E.; MANZOTTI, C.; OLIVA, A.; SPINELLI, S.; TOGNELLA, S.; J. Med. Chem. 37 (1994) 6, 828-837; Dep.

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The functional importance of ribose moieties in both exons and in intron sequences proximal to the 3' splice site of a group I intron has been analyzed using a novel exon polymerization reaction. The ribozyme is a modified version of a self-splicing bacterial tRNA intron (I) that attacks a 20-nucleotide synthetic ligated exon substrate (E1.E2), yielding E1 and I.E2 by reverse exon ligation. A series of repetitive reactions then polymerize E2 on the 3' end of the intron; attack by E1 subsequently generates E1.(E2)n. Systematic deoxyribonucleotide substitution within E1.E2 was used to probe the function of 2'-hydroxyl groups in each exon and the 3'-terminal nucleotides of the intron. We find that ribose at the splice junction (U-1) and at the two adjacent positions with E1 (A-2, C-3) is important for reverse exon ligation. Within E2, deletion of 2'-hydroxyl groups of the nucleotides that form P10 does not affect reactivity. In contrast, ribose at the 3' end of the intron is essential for reverse exon ligation, and the presence of a 2'-OH group in each of the nucleotides comprising P9.0[3'] contributes to reaction efficiency. These results support a model in which specific 2'-hydroxyl groups at and adjacent to the reaction sites form tertiary contacts that serve to stabilize interactions with the catalytic core of the ribozyme. Furthermore, they suggest that the mechanism by which guanosine at the 3' end of the intron is activated for reverse exon ligation is the same as that by which guanosine mononucleotide is activated in the first step of splicing.