325 research outputs found

    Assessing the hydrodynamic performance of vegetation physical models: an experimental study of seaweed blades

    Get PDF
    Seaweed blades and seaweed blade physical models designed following a similarity theory were tested in a flume facility. The measured drag coefficient of physical models is found to be significantly biased low compared to that of natural seaweed blades

    Innovative approaches for measuring organism stress and behavioural integrity in flume facilities: Deliverable D8-IV

    Get PDF
    HYDRALAB+ aims to improve the usefulness and value of hydraulic laboratory facilities and is developing experimental guidelines that will allow researchers to successfully investigate complex scenarios representative of natural environments in a context of climate change. Within this framework it is often important to incorporate relevant biological elements in physical experiments, including the use of live vegetation. Notwithstanding efforts to maintain their health by careful husbandry, plants typically degenerate when introduced to flume settings. Physiological responses to degenerating health can affect their interactions with the flow so that experimental conditions are not representative of healthy specimens in situ. There is therefore a need to measure and evaluate the health of plants being used in hydraulic facilities, especially since behavioural integrity might be reduced before there are obvious signs of degeneration. Such measurements are not routinely made so there is a need to identify measurement techniques and methodological protocols for assessing vegetation health status in hydraulic laboratories. This deliverable identifies a technique established in plant physiology and horticulture for monitoring vegetation health status and shows how it can be applied in hydraulic laboratories with minimal impact on organisms. A simple and suitable test among those established in the relevant literature is validated by conducting experiments on freshwater macrophytes. From the relevant literature and the results of experiments reported herein, this deliverable provides an overview of the technique identified and establishes practical guidance on how to properly apply it in hydraulic experiments. The methodological protocol developed can potentially be integrated into established protocols used in ecohydraulics studies as a simple proxy of vegetation health status

    3D printed masks for powders and viruses safety protection using food grade polymers: Empirical tests

    Get PDF
    The production of 3D printed safety protection devices (SPD) requires particular attention to the material selection and to the evaluation of mechanical resistance, biological safety and surface roughness related to the accumulation of bacteria and viruses. We explored the possibility to adopt additive manufacturing technologies for the production of respirator masks, responding to the sudden demand of SPDs caused by the emergency scenario of the pandemic spread of SARS‐COV‐ 2. In this study, we developed different prototypes of masks, exclusively applying basic additive manufacturing technologies like fused deposition modeling (FDM) and droplet‐based precision extrusion deposition (db‐PED) to common food packaging materials. We analyzed the resulting mechanical characteristics, biological safety (cell adhesion and viability), surface roughness and resistance to dissolution, before and after the cleaning and disinfection phases. We showed that masks 3D printed with home‐grade printing equipment have similar performances compared to the industrial‐grade ones, and furthermore we obtained a perfect face fit by customizing their shape. Finally, we developed novel approaches to the additive manufacturing post‐processing phases essential to assure human safety in the production of 3D printed custom medical devices

    Guidance on the assessment of the safety of feed additives for the environment

    Get PDF
    This guidance document is intended to assist the applicant in the preparation and the presentation of an application, as foreseen in Article 7.6 of Regulation (EC) No 1831/2003, for the authorisation of additives used in animal nutrition. It specifically covers the assessment of the safety for the environment. (Table presented.)

    Efficacy of Bacillus subtilis DSM 28343 as a zootechnical additive (gut flora stabiliser) for calves for rearing

    Get PDF
    Bacillus subtilis DSM 28343 is a preparation of viable spores of a single strain of B. subtilis intended to be used as a zootechnical additive (functional group: gut flora stabilizer) in feed for calves for rearing to increase growth. In 2018, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) delivered a scientific opinion on the safety and efficacy of Bacillus subtilis DSM 28343 as a feed additive for calves for rearing. This species is considered by EFSA to be suitable for the qualified presumption of safety (QPS) approach to safety assessment. In that opinion, the FEEDAP Panel was unable to conclude on the efficacy of the additive, under the condition of use as proposed by the applicant, due to insufficient data provided. In the current opinion, additional data to demonstrate the efficacy of Bacillus subtilis DSM 28343 were assessed. Based on one study of this application and two studies submitted in the previous application, the Panel concluded that Bacillus subtilis DSM 28343 has the potential to be efficacious as gut flora stabiliser used in feed for calves for rearing at the proposed use level

    Assessment of the application for renewal of authorisation of Bactocell ® (Pediococcus acidilactici CNCM I-4622) as a feed additive for all fish and shrimps and its extension of use for all crustaceans

    Get PDF
    Bactocell \uae is the trade name for a feed additive based on viable cells of a strain of Pediococcus acidilactici. Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on Bactocell \uae  in the context of the renewal of the authorisation for shrimps, salmonids and fish other than salmonids. In addition, the applicant requested the extension of use for all crustaceans. The applicant has provided evidence that the additive currently in the market complies with the existing conditions of authorisation. The FEEDAP Panel concludes that Bactocell \uae Aqua 10 Md/100 Md is safe under the current conditions of authorisation for the target species (all fish, shrimps and all crustaceans), consumers of products from animals fed the additive and the environment. Bactocell \uae Aqua 10 Md/100 Md is non-irritant to skin and eyes and is not a dermal sensitiser, but should be considered a potential respiratory sensitiser. Exposure of users by inhalation is very likely. There is no need for assessing the efficacy of Bactocell \uae in the context of the renewal of the authorisation. The Panel concludes that the additive at the minimum inclusion level of 1  7 10 9  CFU/kg feed has the potential to be efficacious in salmonids and in the new species proposed, i.e. all crustaceans

    Safety and efficacy of Natuphos® E (6-phytase) as a feed additive for laying hens, minor poultry and other avian species for laying

    Get PDF
    Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of Natuphos\uae E (6-phytase) as a feed additive for laying hens, minor poultry and other avian species for laying. The additive Natuphos\uae E consists of 6-phytase (phytase; Enzyme Commission Number 3.1.3.26) and is intended to be used as a feed additive for laying hens, minor poultry and other avian species for laying as a zootechnical additive, functional group of digestibility enhancers. This additive was previously assessed by the FEEDAP Panel in 2017 for avian and porcine species. The production strain of the phytase present in the product is a genetically modified strain of Aspergillus niger. Based on the previous opinion, the FEEDAP Panel concluded that the genetic modification of the production strain does not give rise to safety concerns. The production strain and its DNA were not detected in the concentrate used to formulate the products. The FEEDAP Panel previously concluded that the additive was safe for the target species, consumers and the environment when used at 200 FTU/kg feed. The additive Natuphos\uae E is not considered to be toxic by inhalation or irritant for skin or eye; however, it should be regarded as a dermal sensitiser and a potential respiratory sensitiser. The additive has the potential to be efficacious in improving the performance and/or the phosphorus utilisation in laying hens at 200 FTU/kg feed; the conclusions drawn in laying hens can be extrapolated to all minor poultry and other avian species for laying

    Avaliação do estado nutricional de agroecossistemas de café orgùnico no estado de Minas Gerais.

    Get PDF
    A produção de cafĂ© orgĂąnico vem se constituindo uma tendĂȘncia necessĂĄria e irreversĂ­vel do agronegĂłcio brasileiro. Essa atividade tem-se destacado como uma alternativa de renda para alguns cafeicultores, devido Ă  crescente demanda mundial por alimentos mais saudĂĄveis. Entretanto, grande parte das tĂ©cnicas propostas pela agricultura orgĂąnica estĂĄ sendo aplicada empiricamente no cultivo de cafĂ©, principalmente no Estado de Minas Gerais, maior regiĂŁo produtora de cafĂ© do Brasil. Levando-se em consideração a baixa fertilidade natural dos solos dessa regiĂŁo cafeeira, bem como a elevada extração de nutrientes pelo cafeeiro, objetivou-se neste trabalho identificar possĂ­veis fatores limitantes para a produção orgĂąnica do cafeeiro, relacionados Ă  fertilidade do solo e ao estado nutricional das plantas. Foram realizadas avaliaçÔes da fertilidade do solo e anĂĄlise das folhas em vinte e uma lavouras orgĂąnicas representativas do Estado de Minas Gerais. As amostras de solo foram analisadas para determinação do pH, acidez potencial e dos teores de P, K, Ca, Mg, S, Al e matĂ©ria orgĂąnica. As amostras foliares foram analisadas para determinação dos teores de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. Com base nos padrĂ”es de interpretação para cafeeiros convencionais propostos pela literatura, estabeleceram-se as freqĂŒĂȘncias com que os caracteres analisados foram inferiores aos critĂ©rios de interpretação da fertilidade do solo e estado nutricional das plantas. A anĂĄlise dos dados foi realizada por estatĂ­stica descritiva. Novos trabalhos nessa nova ĂĄrea sĂŁo necessĂĄrios, visando a uma melhor interpretação da anĂĄlise foliar e da fertilidade do solo, quando se trabalha com cafĂ© orgĂąnico

    Safety and efficacy of lutein and lutein/zeaxanthin extracts from Tagetes erecta for poultry for fattening and laying (except turkeys)

    Get PDF
    The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) evaluated (i) lutein from a saponified extract from Tagetes erecta obtained via extraction and saponification (lutein not less than 85% of total carotenoids (TC)) and (ii) lutein/zeaxanthin extract from Tagetes erecta obtained via extraction, saponification and isomerisation (lutein not less than 45% and zeaxanthin not less than 35% of TC). The maximum proposed use level of 80 mg TC from saponified Tagetes extract/kg complete feed for chickens for fattening and laying hens is safe for these animal categories. This conclusion can be extrapolated to minor poultry species for fattening and laying. The conclusions on saponified Tagetes extract for poultry for fattening and laying are extended to the saponified/isomerised Tagetes extract. The maximum use level of the saponified/isomerised Tagetes extract in breeding minor poultry should not exceed 50 mg TC/kg feed, considering the toxicological potential of zeaxanthin on reproduction. The saponified Tagetes extract is not genotoxic. This conclusion is extended to the saponified/isomerised Tagetes extract. Consumer exposure related to the consumption of animal products is very low compared to the exposure from other sources. The active substance is a viscous paste and may be irritant to skin and eyes; no exposure by inhalation is expected. In the absence of data, the Panel cannot conclude on the safety for the user of commercial preparations. The use of Tagetes extracts in poultry feed raised no concern for the environment. Tagetes extracts at levels up to the proposed maximum use level of 80 mg TC/kg complete feed have the potential to colour the egg yolk of laying hens and the skin of chickens for fattening. This conclusion is extended to minor poultry species for laying and for fattening. The use of the additive in feed and water for drinking is considered bioequivalent

    Modification of the conditions of the authorisation of BioPlus® 2B (Bacillus licheniformis DSM 5749 and Bacillus subtilis DSM 5750) for turkeys for fattening

    Get PDF
    Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the modification of the terms of the authorisation of BioPlus\uae 2B (Bacillus licheniformis DSM 5749 and Bacillus subtilis DSM 5750) in feeds for turkeys for fattening to allow the simultaneous use with a battery of permitted coccidiostats (diclazuril, halofuginone, monensin sodium, robenidine hydrochloride, maduramicin ammonium, lasalocid sodium) and with the preservative formic acid. The proposed modification in the conditions of the authorisation would not modify the conclusions previously drawn regarding the safety of the additive. The additive is safe for the target species, consumers and the environment. The additive should be considered a potential respiratory sensitiser, but the Panel could not conclude on the irritancy of the additive to skin and eyes or its dermal sensitisation. Conclusions previously drawn by the FEEDAP Panel on the compatibility of the additive for chickens for fattening apply to the current application provided that the maximum authorised concentration of the coccidiostats semduramycin, maduramicin ammonium, lasalocid sodium and the preservative formic acid for turkeys for fattening (when maximum authorised concentrations exist), are equal or lower than those for chickens for fattening. Considering the data submitted, the FEEDAP Panel concludes that BioPlus\uae 2B (B. licheniformis DSM 5749 and B. subtilis DSM 5750) is compatible with diclazuril and monensin sodium. Based on the data provided, no conclusion can be drawn for robenidine hydrochloride. In the absence of data, no conclusion can be drawn for halofuginone
    • 

    corecore