81 research outputs found

    Production of ornamental plants and cut flowers in peri-urban areas: An economic and environmental analysis of the Barcelona Metropolitan region, Spain

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    Ornamental plants and floral plants are not usually considered in research works on urban agriculture. On the contrary, the main stream of research is focused on food production. An essential feature of ornamental plant markets is that they are global. Most of consumers ornamental plants and cut flowers are located in Europe, United States of America and Japan, and the emerging producers are located in South America and Africa. Ornamental crops present a very high added value, if they are compared with vegetables and fruits, or crops like cereals. Ornamental plants and cut flowers production needs a high level of technology to control the irrigation system (soilless culture), the environment (temperature, humidity, light) and the postharvest. The aim of this study is the evaluation of the technological level used by urban farmers. More specifically, this objective can be achieved through the next questions: How to be competitive in the ornamental global market? Which are the advantages of these farmers being located in urban areas? Which channels do they use to sell their production? A semi – structured survey was conducted of ornamental and cut flowers farmers in Barcelona Metropolitan Region (Catalonia, Spain). The survey was approved by the working group of Entrepreneurial Models of Urban Agriculture within the framework of the European project Cost Action TD 1106 Urban Agriculture Europe. © 2018 WIT Press.Postprint (published version

    Field margins in Spain; proposal of common descriptors

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    Los márgenes de los campos reciben muchas denominaciones locales (linderos, ribazos, etc.) y pueden ser motivo de preocupación para los agricultores por albergar especies arvenses que pueden devenir infestantes del cultivo. Pero su estudio también ha reflejado que pueden ser beneficiosos si albergan diversidad vegetal, la que atraería a su vez diversidad animal. Estudios recientes realizados en España arrojan resultados aparentemente contradictorios y por este motivo se realiza una descripción de la tipología de márgenes existentes en España. Se constata que las diferencias de anchura, altura y pendiente entre márgenes, el tipo de vegetación cercano, así como la intensidad de la perturbación que se ejerce en ellos son posiblemente los principales factores que explican porqué algunos márgenes albergan especies potencialmente nocivas (malas hierbas) y otros no.The field margins receive many local names and can cause trouble to farmers if they host weeds that can infest the nearby fields. But their study has shown that they be beneficial if they harbor vegetal diversity, which can attract animal diversity. Recent studies conducted in Spain show apparently contradictory results an due to this, a description of the margin types found in this country is shown in this communication. We confirm that differences in margins width, height and slope, the type of natural vegetation in the area and the disturbance intensity on the margins are probably the main factors explaining why some margins host potentially harmful plant species (weeds) and others do not

    Predictive phytotoxic value of water-soluble allelochemicals in plant extracts for choosing a cover crop or mulch for specific weed control

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    Cover crops and mulches have become an alternative for soil management in vineyards due to the agronomic, environmental, and economic advantages, especially the possibility of weed control. Implicitly to this objective lies the idea of assessing the potential herbicide effect of the allelochemicals released by different cover crop and mulch species. With this objective, the present work evaluated the phytotoxic effects of 12 aqueous extracts of selected species with potential use as a cover crop or mulch: a Bromus species mixture (B. hordeaceus L. and B. rubens L.), Festuca arundinacea Schreb., Hordeum murinum L., H. vulgare L., Vulpia ciliata Dumort.,  Medicago rugosa Desr., M. sativa L., Trifolium subterraneum L., T. incarnatum L., Phacelia tanacetifolia Benth., Sinapis alba L., and Pinus sylvestris L.,on the germination and early growth of three troublesome weeds (Conyza bonariensis (L.) Cronquist, Aster squamatus (Spreng.) Hieron, and Bassia scoparia (L.) A. J.). The different in vitro bioassays showed that aqueous extracts of some species significantly inhibited or reduced germination and root and shoot growth of the target weed species in a dose-response manner. Germination of A. squamatus and C. bonariensis was reduced by 100-80% by the different extracts applied at 50% concentration, and completely blocked at 100% concentration, except for M rugosa extract to which both species showed less sensitivity. Root elongation of A. squamatus was absolutely inhibited under every extract and concentration, whereas C. bonariensis root growth showed only some tolerance to the crude extracts of F. arundinaceaand P. sylvestris. Bassia scoparia was relatively tolerant to the aqueous plant extracts, except for T. subterraneum crude extract, which reduced total germination by 80%; otherwise, B. scoparia showed higher general sensitivity of shoot growth than the other two weed species. The chemical profiles of phenolic compounds of the aqueous extracts were obtained and identified by HPLC-DAD, the phenolic profiles of H. murinum, V. ciliata, and M. rugosa being reported in this work for the first time. Using stepwise regression, the influence of certain phenolic compounds from the aqueous extracts on the germination and early growth of weeds was predicted. Among other significant compounds, the flavonoid naringenin identified in T. subterraneumaqueous extract at 8.09 µg·mL-1 was predicted to underlie its specific phytotoxicity on B. scoparia germination. These results support the use of cover crops and mulches in weed management and can help to select the most suitable species to adopt according to the target weed species. Highlights • The phytotoxic nature of the aqueous extracts of twelve conventional and novel cover crops and mulch species was demonstrated on three troublesome weed species in vineyards. • Phenolic acids and flavonoids of the twelve aqueous extracts were identified and quantified by HPLC-DAD, and, by regression analysis, some allelochemicals were postulated as responsible for the phytotoxic effects. • The water-soluble phenolic profiles of three potential cover crops, namely Hordeum murinum, Vulpia ciliata, and Medicago rugosa, are reported for the first time. • In vitro germination and early root growth of Conyza bonariensis and Aster squamatus were almost entirely restricted by any of the twelve plants' aqueous extracts and presumably by the joint action of their particular allelopathic compounds. • Bassia scoparia germination was relatively much less sensitive to the extracts, except for Trifolium subterraneum, for which the flavonoid naringenin was predicted to underlie its specific phytotoxicity

    Comparison of Pheochromocytoma-Specific Morbidity and Mortality among Adults with Bilateral Pheochromocytomas Undergoing Total Adrenalectomy vs Cortical-Sparing Adrenalectomy

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    Importance: Large studies investigating long-term outcomes of patients with bilateral pheochromocytomas treated with either total or cortical-sparing adrenalectomies are needed to inform clinical management. Objective: To determine the association of total vs cortical-sparing adrenalectomy with pheochromocytoma-specific mortality, the burden of primary adrenal insufficiency after bilateral adrenalectomy, and the risk of pheochromocytoma recurrence. Design, Setting, and Participants: This cohort study used data from a multicenter consortium-based registry for 625 patients treated for bilateral pheochromocytomas between 1950 and 2018. Data were analyzed from September 1, 2018, to June 1, 2019. Exposures: Total or cortical-sparing adrenalectomy. Main Outcomes and Measures: Primary adrenal insufficiency, recurrent pheochromocytoma, and mortality. Results: Of 625 patients (300 [48%] female) with a median (interquartile range [IQR]) age of 30 (22-40) years at diagnosis, 401 (64%) were diagnosed with synchronous bilateral pheochromocytomas and 224 (36%) were diagnosed with metachronous pheochromocytomas (median [IQR] interval to second adrenalectomy, 6 [1-13] years). In 505 of 526 tested patients (96%), germline mutations were detected in the genes RET (282 patients [54%]), VHL (184 patients [35%]), and other genes (39 patients [7%]). Of 849 adrenalectomies performed in 625 patients, 324 (52%) were planned as cortical sparing and were successful in 248 of 324 patients (76.5%). Primary adrenal insufficiency occurred in all patients treated with total adrenalectomy but only in 23.5% of patients treated with attempted cortical-sparing adrenalectomy. A third of patients with adrenal insufficiency developed complications, such as adrenal crisis or iatrogenic Cushing syndrome. Of 377 patients who became steroid dependent, 67 (18%) developed at least 1 adrenal crisis and 50 (13%) developed iatrogenic Cushing syndrome during median (IQR) follow-up of 8 (3-25) years. Two patients developed recurrent pheochromocytoma in the adrenal bed despite total adrenalectomy. In contrast, 33 patients (13%) treated with successful cortical-sparing adrenalectomy developed another pheochromocytoma within the remnant adrenal after a median (IQR) of 8 (4-13) years, all of which were successfully treated with another surgery. Cortical-sparing surgery was not associated with survival. Overall survival was associated with comorbidities unrelated to pheochromocytoma: of 63 patients who died, only 3 (5%) died of metastatic pheochromocytoma. Conclusions and Relevance: Patients undergoing cortical-sparing adrenalectomy did not demonstrate decreased survival, despite development of recurrent pheochromocytoma in 13%. Cortical-sparing adrenalectomy should be considered in all patients with hereditary pheochromocytoma

    Cyclized NDGA modifies dynamic α-synuclein monomers preventing aggregation and toxicity.

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    Growing evidence implicates α-synuclein aggregation as a key driver of neurodegeneration in Parkinson's disease (PD) and other neurodegenerative disorders. Herein, the molecular and structural mechanisms of inhibiting α-synuclein aggregation by novel analogs of nordihydroguaiaretic acid (NDGA), a phenolic dibenzenediol lignan, were explored using an array of biochemical and biophysical methodologies. NDGA analogs induced modest, progressive compaction of monomeric α-synuclein, preventing aggregation into amyloid-like fibrils. This conformational remodeling preserved the dynamic adoption of α-helical conformations, which are essential for physiological membrane interactions. Oxidation-dependent NDGA cyclization was required for the interaction with monomeric α-synuclein. NDGA analog-pretreated α-synuclein did not aggregate even without NDGA-analogs in the aggregation mixture. Strikingly, NDGA-pretreated α-synuclein suppressed aggregation of naïve untreated aggregation-competent monomeric α-synuclein. Further, cyclized NDGA reduced α-synuclein-driven neurodegeneration in Caenorhabditis elegans. The cyclized NDGA analogs may serve as a platform for the development of small molecules that stabilize aggregation-resistant α-synuclein monomers without interfering with functional conformations yielding potential therapies for PD and related disorders

    Role of antioxidant enzymes and small molecular weight antioxidants in the pathogenesis of age-related macular degeneration (AMD)

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    Production of ornamental plants and cut flowers in peri-urban areas: An economic and environmental analysis of the Barcelona Metropolitan region, Spain

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    Ornamental plants and floral plants are not usually considered in research works on urban agriculture. On the contrary, the main stream of research is focused on food production. An essential feature of ornamental plant markets is that they are global. Most of consumers ornamental plants and cut flowers are located in Europe, United States of America and Japan, and the emerging producers are located in South America and Africa. Ornamental crops present a very high added value, if they are compared with vegetables and fruits, or crops like cereals. Ornamental plants and cut flowers production needs a high level of technology to control the irrigation system (soilless culture), the environment (temperature, humidity, light) and the postharvest. The aim of this study is the evaluation of the technological level used by urban farmers. More specifically, this objective can be achieved through the next questions: How to be competitive in the ornamental global market? Which are the advantages of these farmers being located in urban areas? Which channels do they use to sell their production? A semi – structured survey was conducted of ornamental and cut flowers farmers in Barcelona Metropolitan Region (Catalonia, Spain). The survey was approved by the working group of Entrepreneurial Models of Urban Agriculture within the framework of the European project Cost Action TD 1106 Urban Agriculture Europe. © 2018 WIT Press
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