7,546 research outputs found

    Polyphenols and organic acids as alternatives to antimicrobials in poultry rearing: a review.

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    For decades antibiotics have been used in poultry rearing to support high levels of production. Nevertheless, several problems have arisen because of the misuse of antibiotics (i.e., antibiotic resistance, residues in animal products, environmental pollution). Thus, the European Union (EU) as well as the European Food Safety Authority (EFSA) promote action plans to diminish the use of antibiotics in animal production. Alternatives to antibiotics have been studied. Polyphenols (PPs) or organic acids (OAs) seem to be two accredited solutions. Phenolic compounds, such as phenols, flavonoids, and tannins exert their antimicrobial effect with specific mechanisms. In contrast, short chain fatty acids (SCFAs) and medium chain fatty acids (MCFAs), the OAs mainly used as antibiotics alternative, act on the pathogens depending on the pKa value. This review aims to collect the literature reporting the effects of these substances applied as antimicrobial molecules or growth promoter in poultry feeding (both for broilers and laying hens). Organic acids and PPs can be used individually or in blends, exploiting the properties of each component. Collected data highlighted that further research needs to focus on OAs in laying hens’ feeding and also determine the right combination in blends with PPs

    Maslow’s Hammer for Catastrophic Forgetting: Node Re-Use vs Node Activation

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    Continual learning—learning new tasks in sequence while maintaining performance on old tasks—remains particularly challenging for artificial neural networks. Surprisingly, the amount of forgetting does not increase with the dissimilarity between the learned tasks, but appears to be worst in an intermediate similarity regime. In this paper we theoretically analyse both a synthetic teacher-student framework and a real data setup to provide an explanation of this phenomenon that we name Maslow’s Hammer hypothesis. Our analysis reveals the presence of a trade-off between node activation and node re-use that results in worst forgetting in the intermediate regime. Using this understanding we reinterpret popular algorithmic interventions for catastrophic interference in terms of this trade-off, and identify the regimes in which they are most effective

    Allergic fungal rhinosinusitis infiltrating anterior skull base and clivus.

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    Bone erosion and skull base invasion are often suggestive of a malignant mass in paranasal and nasal cavities. Nevertheless, forms of chronic rhinosinusitis, such as allergic fungal rhinosinusitis (AFRS), could mimic malignant features. Here, we report AFRS patient with orbital, anterior cranial fossa, Turkish saddle and clivus erosion. A 48-year-old Caucasian female with history of drug-resistant headache, nasal obstruction and anosmia was referred to our institution. Imaging showed hyperdense featureless tissue with signs of medial orbital wall, cribiform lamina and clivus erosions and encasement of right internal carotid artery. Massive amounts of thick and grayish mucoid material were evacuated during surgery. In case of bony erosion, malignancy should always be excluded. Often the correct diagnosis will be obtained only by operative specimens. AFRS could usually be managed endoscopically. Appropriate medical management of the AFRS should be administered in order to prevent relapses
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