The growth effects of EU cohesion policy: a meta-analysis. Bruegel Working Paper 2012/14, October 2012

We run a standard income convergence analysis for the last decade and confirm an already established finding in the growth economics literature. EU countries are converging. Regions in Europe are also converging. But, within countries, regional disparities are on the rise. At the same time, there is probably no reason for EU Cohesion Policy to be concerned with what happens inside countries. Ultimately, our data shows that national governments redistribute well across regions, whether they are fiscally centralised or decentralised. It is difficult to establish if Structural and Cohesion Funds play any role in recent growth convergence patterns in Europe. Generally, macroeconomic simulations produce better results than empirical tests. It is thus possible that Structural Funds do not fully realise their potential either because they are not efficiently allocated or are badly managed or are used for the wrong investments, or a combination of all three. The approach to assess the effectiveness of EU funds should be consistent with the rationale behind the post-1988 EU Cohesion Policy. Standard income convergence analysis is certainly not sufficient and should be accompanied by an assessment of the changes in the efficiency of the capital stock in the recipient countries or regions as well as by a more qualitative assessment. EU funds for competitiveness and employment should be allocated by looking at each region’s capital efficiency to maximise growth generating effects or on a pure competitive.

Três ensaios sobre o mercado de trabalho no Brasil

Esta tese é composta por três artigos e uma nota, sendo um em cada capítulo. Todos os capítulos enquadram-se na área de Microeconomia Aplicada e Economia do Trabalho. O primeiro artigo estende o modelo tradicional de decomposição das flutuações na taxa de desemprego de Shimer (2012), separando o emprego formal do informal. Com essa modificação, os principais resultados da metodologia se alteram e conclui-se que os principais fatores para a queda do desemprego na última década foram (i) a queda na taxa de participação, principalmente pela menor entrada na força de trabalho; (ii) o aumento da formalização, atingido tanto pelo aumento da probabilidade de encontrar um trabalho formal quanto pela probabilidade de deixar a condição de empregado formal. O segundo capítulo apresenta estimativas para o retorno à educação no Brasil, utilizando uma nova metodologia que não necessita de variáveis de exclusão. A vantagem do método em relação a abordagens que utilizam variáveis instrumentais é a de permitir avaliar o retorno médio para todos os trabalhadores (e não somente os afetados pelos instrumentos) e em qualquer instante do tempo. Face aos resultados, concluímos as estimativas via MQO subestimam o retorno médio. Discute-se possíveis explicações para esse fenômeno. O terceiro artigo trata da terceirização da mão de obra no Brasil. Mais especificamente, mede-se o diferencial de salários entre os trabalhadores terceirizados e os contratados diretamente. Os resultados de uma comparação não condicional indicam que os terceirizados têm salário médio 17% menor no período 2007 a 2012. Porém, com estimativas que levam em conta o efeito fixo de cada trabalhador, esse diferencial cai para 3,0%. Além disso, o diferencial é bastante heterogêneo entre os tipos de serviços: aqueles que utilizam trabalhadores de baixa qualificação apresentam salário menores, enquanto nas ocupações de maior qualificação os terceirizados têm salários iguais ou maiores do que os diretamente contratados. Mais ainda, as evidencias apontam para a diminuição do diferencial ao longo do tempo no período analisado. Finalmente, a nota que encerra a tese documenta dois aspectos relevantes e pouco conhecidos da Pesquisa Mensal de Emprego do IBGE que podem levar a resultados imprecisos nas pesquisas que utilizam esse painel se não forem tratados adequadamente.

3D calculation of Tucson-Melbourne 3NF effect in triton binding energy

As an application of the new realistic three-dimensional (3D) formalism reported recently for three-nucleon (3N) bound states, an attempt is made to study the effect of three-nucleon forces (3NFs) in triton binding energy in a non partial wave (PW) approach. The spin-isospin dependent 3N Faddeev integral equations with the inclusion of 3NFs, which are formulated as function of vector Jacobi momenta, specifically the magnitudes of the momenta and the angle between them, are solved with Bonn-B and Tucson-Melbourne NN and 3N forces in operator forms which can be incorporated in our 3D formalism. The comparison with numerical results in both, novel 3D and standard PW schemes, shows that non PW calculations avoid the very involved angular momentum algebra occurring for the permutations and transformations and it is more efficient and less cumbersome for considering the 3NF.

Delimitação e alinhamento de conceitos lexicalizados no inglês norte-americano e no português brasileiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

La enseñanza del español en el sistema universitario brasileño: propuesta para una buena práctica docente

O recente crecemento significativo do ensino de español no Brasil e a consecuente necesidade de formar profesores desta lingua ven demandando das institucións de Ensino Superior un coidado especial no proceso de formación de futuros docentes. Así, o obxecto de estudo desta tese céntrase na docencia, en súas múltiples dimensións pedagóxicas. O obxectivo xeral é o de analizar, segundo a perspectiva dos autores referenciados, as implicacións do traballo docente no desenvolvemento do proceso de ensino-aprendizaxe nas disciplinas que tratan especificamente da Lingua e Cultura Hispanófona nos Graos en Letras-Español en dúas universidades Ŕ a Universidade Federal do Pará e a Universidade da Amazônia, situadas na cidade de Belém, no estado do Pará (Brasil). Derivadas deste obxectivo formuláronse preguntas, dirixidas a profesores e alumnos, que orientaron o desenvolvemento do estudo. A opción metodolóxica adoptada ten como fundamento os principios da abordaxe cuanticualitativa, considerando os presupostos do paradigma fenomenolóxico, con procedementos descriptivoanalíticos, na perspectiva da triangulación de métodos e suxeitos como unha forma de integrar os diferentes aspectos do estudo. Participaron como suxeitos da investigación profesores e alumnos das dúas institucións. Os dados foron recollidos vía análise documental, cuestionarios con preguntas abertas e pechadas e entrevistas semiestruturadas. As respostas ás preguntas pechadas dos cuestionarios foron traballadas con procedementos estatísticos descritivos e as respostas ás preguntas abertas e as entrevistas foron analizadas con procedementos específicos da análise de contido. Os resultados revelaron que as prácticas docentes presentan algúns puntos críticos, centrados principalmente na planificación, no proceso avaliador, na infraestrutura e no clima relacional. Sen embargo, estas dificultades non se constitúen en obstáculos insuperables, incluso porque outros aspectos foron valorados positivamente por profesores e alumnos, principalmente os relacionados co traballo co contido, os procedementos metodolóxicos e o uso dos recursos didácticos. De maneira xeral, existe unha manifesta opinión positiva en relación á práctica docente dos profesores das dúas institucións. Da análise destes resultados derívanse algunhas recomendacións que poderán contribuír para unha reflexión conxunta da comunidade implicada con vistas ó perfeccionamento da práctica docente nos Grados de Licenciatura en Letras-Español en Brasil.

Methods and strategies to identify the mode of action of phytoactive compounds

Small molecules affecting biological processes in plants are widely used in agricultural practice as herbicides or plant growth regulators and in basic plant sciences as probes to study the physiology of plants. Most of the compounds were identified in large screens by the agrochemical industry, as phytoactive natural products and more recently, novel phytoactive compounds originated from academic research by chemical screens performed to induce specific phenotypes of interest. The aim of the present PhD thesis is to evaluate different approaches used for the identification of the primary mode of action (MoA) of a phytoactive compound. Based on the methodologies used for MoA identification, three approaches are discerned: a phenotyping approach, an approach based on a genetic screen and a biochemical screening approach.rnFour scientific publications resulting from my work are presented as examples of how a phenotyping approach can successfully be applied to describe the plant MoA of different compounds in detail.rnI. A subgroup of cyanoacrylates has been discovered as plant growth inhibitors. A set of bioassays indicated a specific effect on cell division. Cytological investigations of the cell division process in plant cell cultures, studies of microtubule assembly with green fluorescent protein marker lines in vivo and cross resistant studies with Eleusine indica plants harbouring a mutation in alpha-tubulin, led to the description of alpha-tubulin as a target site of cyanoacrylates (Tresch et al., 2005).rnII. The MoA of the herbicide flamprop-m-methyl was not known so far. The studies described in Tresch et al. (2008) indicate a primary effect on cell division. Detailed studies unravelled a specific effect on mitotic microtubule figures, causing a block in cell division. In contrast to other inhibitors of microtubule rearrangement such as dinitroanilines, flamprop-m-methyl did not influence microtubule assembly in vitro. An influence of flamprop-m-methyl on a target within the cytoskeleton signalling network could be proposed (Tresch et al., 2008).rnIII. The herbicide endothall is a protein phosphatase inhibitor structurally related to the natural product cantharidin. Bioassay studies indicated a dominant effect on dark-growing cells that was unrelated to effects observed in the light. Cytological characterisation of the microtubule cytoskeleton in corn tissue and heterotrophic tobacco cells showed a specific effect of endothall on mitotic spindle formation and ultrastructure of the nucleus in combination with a decrease of the proliferation index. The observed effects are similar to those of other protein phosphatase inhibitors such as cantharidin and the structurally different okadaic acid. Additionally, the observed effects show similarities to knock-out lines of the TON1 pathway, a protein phosphatase-regulated signalling pathway. The data presented in Tresch et al. (2011) associate endothall’s known in vitro inhibition of protein phosphatases with in vivo-effects and suggest an interaction between endothall and the TON1 pathway.rnIV. Mefluidide as a plant growth regulator induces growth retardation and a specific phenotype indicating an inhibition of fatty acid biosynthesis. A test of the cuticle functionality suggested a defect in the biosynthesis of very-long-chain fatty acids (VLCFA) or waxes. Metabolic profiling studies showed similarities with different groups of VLCFA synthesis inhibitors. Detailed analyses of VLCFA composition in tissues of duckweed (Lemna paucicostata) indicated a specific inhibition of the known herbicide target 3 ketoacyl-CoA synthase (KCS). Inhibitor studies using a yeast expression system established for plant KCS proteins verified the potency of mefluidide as an inhibitor of plant KCS enzymes. It could be shown that the strength of inhibition varied for different KCS homologues. The Arabidopsis Cer6 protein, which induces a plant growth phenotype similar to mefluidide when knocked out, was one of the most sensitive KCS enzymes (Tresch et al., 2012).rnThe findings of my own work were combined with other publications reporting a successful identification of the MoA and primary target proteins of different compounds or compound classes.rnA revised three-tier approach for the MoA identification of phytoactive compounds is proposed. The approach consists of a 1st level aiming to address compound stability, uniformity of effects in different species, general cytotoxicity and the effect on common processes like transcription and translation. Based on these findings advanced studies can be defined to start the 2nd level of MoA characterisation, either with further phenotypic characterisation, starting a genetic screen or establishing a biochemical screen. At the 3rd level, enzyme assays or protein affinity studies should show the activity of the compound on the hypothesized target and should associate the in vitro effects with the in vivo profile of the compound.

La revisione della traduzione editoriale dall'inglese all'italiano tra ricerca accademica, professione e formazione: stato dell'arte e prospettive future

Quando si parla di traduzione, si pensa spesso solo al risultato di un processo, valutato e analizzato come tale. Sembra ci si dimentichi del fatto che, prima di arrivare a quel risultato finale, il traduttore applica più o meno consapevolmente tutta quella serie di strumenti di analisi, critica, correzione, rilettura, riformulazione e modifica che rientrano nell’attività di revisione. A questa prima fase, di cui ogni traduttore fa esperienza nel lavorare alla propria traduzione, segue di norma una fase successiva in cui la traduzione è rivista da un’altra figura professionale della filiera editoriale (di solito, e auspicabilmente, un altro traduttore) e infine altre fasi ancora del processo di lavorazione e pubblicazione del testo tradotto. Oltre a essere un’attività cruciale di ogni attività di traduzione e processo editoriale, la revisione riveste anche un fondamentale ruolo didattico nella formazione dei traduttori. L’idea alla base di questo progetto di ricerca nasce dal bisogno di triangolare riflessioni e dati concreti sulla revisione provenienti dalla ricerca accademica, dalla pratica professionale e dall’esperienza didattico-formativa, in un triplice approccio che informa l’intero progetto, di cui si illustrano i principali obiettivi: • formulare una nuova e chiara definizione sommativa del termine “revisione” da potersi utilizzare nell’ambito della ricerca, della didattica e della prassi professionale; • fornire una panoramica tematica, critica e aggiornata sulla ricerca accademica e non-accademica in materia di revisione; • condurre un’indagine conoscitiva (tramite compilazione di questionari diversificati) sulla pratica professionale della revisione editoriale in Italia, allo scopo di raccogliere dati da traduttori e revisori, fornirne una lettura critica e quindi individuare peculiarità e criticità di questa fase del processo di lavorazione del libro tradotto; • presentare ipotesi di lavoro e suggerimenti su metodi e strumenti da applicare all’insegnamento della revisione in contesti didattici e formativi.

Does pet ownership in infancy lead to asthma or allergy at school age? Pooled analysis of individual participant data from 11 European birth cohorts

Objective To examine the associations between pet keeping in early childhood and asthma and allergies in children aged 6–10 years. Design Pooled analysis of individual participant data of 11 prospective European birth cohorts that recruited a total of over 22,000 children in the 1990s. Exposure definition Ownership of only cats, dogs, birds, rodents, or cats/dogs combined during the first 2 years of life. Outcome definition Current asthma (primary outcome), allergic asthma, allergic rhinitis and allergic sensitization during 6–10 years of age. Data synthesis Three-step approach: (i) Common definition of outcome and exposure variables across cohorts; (ii) calculation of adjusted effect estimates for each cohort; (iii) pooling of effect estimates by using random effects meta-analysis models. Results We found no association between furry and feathered pet keeping early in life and asthma in school age. For example, the odds ratio for asthma comparing cat ownership with “no pets” (10 studies, 11489 participants) was 1.00 (95% confidence interval 0.78 to 1.28) (I2 = 9%; p = 0.36). The odds ratio for asthma comparing dog ownership with “no pets” (9 studies, 11433 participants) was 0.77 (0.58 to 1.03) (I2 = 0%, p = 0.89). Owning both cat(s) and dog(s) compared to “no pets” resulted in an odds ratio of 1.04 (0.59 to 1.84) (I2 = 33%, p = 0.18). Similarly, for allergic asthma and for allergic rhinitis we did not find associations regarding any type of pet ownership early in life. However, we found some evidence for an association between ownership of furry pets during the first 2 years of life and reduced likelihood of becoming sensitized to aero-allergens. Conclusions Pet ownership in early life did not appear to either increase or reduce the risk of asthma or allergic rhinitis symptoms in children aged 6–10. Advice from health care practitioners to avoid or to specifically acquire pets for primary prevention of asthma or allergic rhinitis in children should not be given.

Statistical model-based segmentation of the proximal femur in digital antero-posterior (AP) pelvic radiographs.

PURPOSE    Segmentation of the proximal femur in digital antero-posterior (AP) pelvic radiographs is required to create a three-dimensional model of the hip joint for use in planning and treatment. However, manually extracting the femoral contour is tedious and prone to subjective bias, while automatic segmentation must accommodate poor image quality, anatomical structure overlap, and femur deformity. A new method was developed for femur segmentation in AP pelvic radiographs. METHODS    Using manual annotations on 100 AP pelvic radiographs, a statistical shape model (SSM) and a statistical appearance model (SAM) of the femur contour were constructed. The SSM and SAM were used to segment new AP pelvic radiographs with a three-stage approach. At initialization, the mean SSM model is coarsely registered to the femur in the AP radiograph through a scaled rigid registration. Mahalanobis distance defined on the SAM is employed as the search criteria for each annotated suggested landmark location. Dynamic programming was used to eliminate ambiguities. After all landmarks are assigned, a regularized non-rigid registration method deforms the current mean shape of SSM to produce a new segmentation of proximal femur. The second and third stages are iteratively executed to convergence. RESULTS    A set of 100 clinical AP pelvic radiographs (not used for training) were evaluated. The mean segmentation error was [Formula: see text], requiring [Formula: see text] s per case when implemented with Matlab. The influence of the initialization on segmentation results was tested by six clinicians, demonstrating no significance difference. CONCLUSIONS    A fast, robust and accurate method for femur segmentation in digital AP pelvic radiographs was developed by combining SSM and SAM with dynamic programming. This method can be extended to segmentation of other bony structures such as the pelvis.

Successful pacing using a batteryless sunlight-powered pacemaker.

AIMS Today's cardiac pacemakers are powered by batteries with limited energy capacity. As the battery's lifetime ends, the pacemaker needs to be replaced. This surgical re-intervention is costly and bears the risk of complications. Thus, a pacemaker without primary batteries is desirable. The goal of this study was to test whether transcutaneous solar light could power a pacemaker. METHODS AND RESULTS We used a three-step approach to investigate the feasibility of sunlight-powered cardiac pacing. First, the harvestable power was estimated. Theoretically, a subcutaneously implanted 1 cm(2) solar module may harvest ∼2500 µW from sunlight (3 mm implantation depth). Secondly, ex vivo measurements were performed with solar cells placed under pig skin flaps exposed to a solar simulator and real sunlight. Ex vivo measurements under real sunlight resulted in a median output power of 4941 µW/cm(2) [interquartile range (IQR) 3767-5598 µW/cm(2), median skin flap thickness 3.0 mm (IQR 2.7-3.3 mm)]. The output power strongly depended on implantation depth (ρSpearman = -0.86, P < 0.001). Finally, a batteryless single-chamber pacemaker powered by a 3.24 cm(2) solar module was implanted in vivo in a pig to measure output power and to pace. In vivo measurements showed a median output power of >3500 µW/cm(2) (skin flap thickness 2.8-3.84 mm). Successful batteryless VVI pacing using a subcutaneously implanted solar module was performed. CONCLUSION Based on our results, we estimate that a few minutes of direct sunlight (irradiating an implanted solar module) allow powering a pacemaker for 24 h using a suitable energy storage. Thus, powering a pacemaker by sunlight is feasible and may be an alternative energy supply for tomorrow's pacemakers.

Index Tracking Using Data-Mining Techniques and Mixed-Binary Linear Programming

Index tracking has become one of the most common strategies in asset management. The index-tracking problem consists of constructing a portfolio that replicates the future performance of an index by including only a subset of the index constituents in the portfolio. Finding the most representative subset is challenging when the number of stocks in the index is large. We introduce a new three-stage approach that at first identifies promising subsets by employing data-mining techniques, then determines the stock weights in the subsets using mixed-binary linear programming, and finally evaluates the subsets based on cross validation. The best subset is returned as the tracking portfolio. Our approach outperforms state-of-the-art methods in terms of out-of-sample performance and running times.

Increasing Derivatives Market Activity in Emerging Markets and Exchange Rate Exposure

Understanding the effects of off-balance sheet transactions on interest and exchange rate exposures has become more important for emerging market countries that are experiencing remarkable growth in derivatives markets. Using firm level data, we report a significant fall in exposure over the past 10 years and relate this to higher derivatives market participation. Our methodology is composed of a three stage approach: First, we measure foreign exchange exposures using the Adler-Dumas (1984) model. Next, we follow an indirect approach to infer derivatives market participation at the firm level. Finally, we study the relationship between exchange rate exposure and derivatives market participation. Our results show that foreign exchange exposure is negatively related to derivatives market participation, and support the hedging explanation of the exchange rate exposure puzzle. This decline is especially salient in the financial sector, for bigger firms, and over longer time periods. Results are robust to using different exchange rates, a GARCH-SVAR approach to measure exchange rate exposure, and different return horizons.

The role of formulation excipients in the development of lyophilised fast-disintegrating tablets

Despite recent Success, many fast-disintegrating tablets (FDTs) still face problems of low mechanical strength, poor mouth-feel and higher disintegration times. This Study aimed to optimise FDTS using a progressive three-stage approach. A series of hardness, fracturability and disintegration time tests were performed on the formulations at each stage. During Stage 1, tablets were prepared in concentrations between 2% and 5% w/w, and were formulated at each concentration as single and combination bloom strength gelatin (BSG) using 75 and 225 BSGs. Analysis revealed that both hardness and disintegration time increased with an increase in gelatin concentration. A combination (5% gelatin) FDT comprising a 50:50 ratio of 75:225 BSGs (hardness: 13.7 +/- 0.9 N and disintegration time: 24.1 +/- 0.6 s) was judged the most ideal, and was carried forward to Stage II: the addition of the saccharides sorbitol, mannitol and sucrose in concentrations between 10% and 80% w/w. The best properties were exhibited by mannitol-containing formulations (50%-hardness: 30.9 +/- 2.8 N and disintegration time: 13.3 +/- 2.1 s), which were carried forward to the next stage: the addition of viscosity-modifying polymers to improve mouth-feel and aid pre-gastric retention. Addition of carbopol 974P-NF resulted in the enhancement of viscosity with a compromise of the hardness of the tablet, whereas Pluronic F127 (6%) showed an increase in disintegration time and viscosity with retention of mechanical propel-ties. (C) 2008 Elsevier B.V. All rights reserved.

Antitumour imidazotetrazines: probes for the major groove of DNA

The antitumour imidazotetrazinones are believed to act as prodrugs for the triazene series of alkylating agents, showing a marked pteference for the alkylation of the middle guanine residue in a run of three or more contiguous guanines. However, the. exact nature of the interactions of imidazotetrazinones within the micro~environment of DNA are; as yet unknown. In order to examine such interactions a three pronged approach involving molecular modelling, synthetic chemistry and biological analysis has been undertaken during the course of this project. . Molecular modelling studies have shown that for the 8-carboxamido substituted imidazotetrazinones antitumour activity is dependent upon the. presence of a free NH group which can be involved in the formation of both intramolecular and intermolecular hydrogen bonds, and the presence of a non-bulky substituent with a small negative potential . volume. Modelling studies involving the docking of .mitozolomide into the major groove of DNA in the region of a triguanine sequence has shown that a number of hydrogen bonding interactions are feasible. A series of 8-substituted carboxamide derivatives of mitozolomide have been synthesised via the 8-acid chloride and 8-carboxylic acid derivatives including a number of peptide analogues. The peptide derivatives were based upon the key structural features of the helix-turn-helix motif of DNA-binding proteins with a view to developing agents that are capable of binding to DNA with greater selectivity. An examination of the importance of intramolecular hydrogen bonding in influencing the antitumour activity:of :the imidazotetrazinones has led to the synthesis of the novel pyrimido[4',5' :4,3]pyrazolo[5,1-d]-1,2,3,5-tetrazine ring system. In general, in vitro cytotoxicity assays showed that the new derivatives were less active against the TLX5 lymphoma cell line. than the parent compound mitozolomide despite an increased potential for hydrogen bonding interactions. Due to the high reactivity of the: tetrazinone ring system it is difficult to study the interactions between the imidazotetrazinones and DNA. Consequently a number of structural analogues that are stable under physiological conditions have been. prepared based upon the 1,2,3 triazin-4(3H)-one ring system fused with both benzene and pyrazole rings. Although the 3-methylbenzotriazinones failed to antagonise the cytotoxic activity of temozolomide encouraging results with a 3-methylpyrazolotriazinone may suggest the existence of an imidazotetrazinone receptor site within DNA. The potential of guanine rich sequences to promote the alkylating selectivity of imidazotetrazinones by acting as a catalyst for ring cleavage and thereby generation of the alkylating agent was examined. Experiments involving the monitoring: of the rate of breakdown of mitozolomide incubated in the presence of synthetic oIigonucleotides did not reveal any catalytic effect resulting from the DNA. However, it was noted that the breakdown of mitozolomide was dependent upon the type of buffer used in the incubations and this may indeed mask any catalysis by the oligonucleotides.

Relative significance of pelagic, benthic and allochthonous organic matter to microbial carbon cycling in a phosphorus-depleted subtropical estuary (Florida Bay)

Heterotrophic bacteria are important decomposers and transformers of primary production and provide an important link between detritus and the aquatic food web. In seagrass ecosystems, much of seagrass primary production is unavailable through direct grazing and must undergo microbial reworking before seagrass production can enter the aquatic food web. The goal of my dissertation research is to understand better the role heterotrophic bacteria play in carbon cycling in seagrass estuaries. My dissertation research focuses on Florida Bay, a seagrass estuary that has experienced recent changes in carbon source availability, which may have altered ecosystem function. My dissertation research investigates the importance of seagrass, algal and/or cyanobacterial, and allochthonous-derived organic matter to heterotrophic bacteria in Florida Bay and helps establish the carbon base of the estuarine food web. ^ A three tiered approach to the study of heterotrophic bacterial carbon cycling and trophic influences in Florida Bay was used: (1) Spatiotemporal observations of environmental parameters (hydrology, nutrients, extracellular enzymes, and microbial abundance, biomass, and production); (2) Microbial grazing experiments under different levels of top-down and bottom-up influence; and (3) Bulk and compound-specific (bacteria-biomarker fatty acid analysis) stable carbon isotope analysis. ^ In Florida Bay, spatiotemporal patterns in microbial extracellular enzyme (also called ectoenzyme) activities indicate that microorganisms hydrolyzed selectively fractions of the estuarine organic matter pool. The microbial community hydrolyzed organic acids, peptides, and phosphate esters and did not use storage and structural carbohydrates. Organic matter use by heterotrophic bacterioplankton in Florida Bay was co-regulated by bottom-up (resource availability) and top-down (grazer mediated) processes. A bacterial carbon budget based on bacterial, epiphytic, and seagrass production indicates that heterotrophic bacterial carbon cycles are supported primarily through epiphytic production with mixing from seagrass production. Stable carbon isotope analysis of bacteria biomarkers and carbon sources in Florida Bay corroborate the results of the bacterial carbon budget. These results support previous studies of aquatic consumers in Florida Bay, indicating that epiphytic/benthic algal and/or cyanobacterial production with mixing from seagrass-derived organic matter is the carbon base of the seagrass estuarine food web. ^