498 research outputs found
An exploratory model-based design of experiments approach to aid parameters identification and reduce model prediction uncertainty
The management of trade-off between experimental design space exploration and information maximization is still an open question in the field of optimal experimental design. In classical optimal experimental design methods, the uncertainty of model prediction throughout the design space is not always assessed after parameter identification and parameters precision maximization do not guarantee that the model prediction variance is minimized in the whole domain of model utilization. To tackle these issues, we propose a novel model-based design of experiments (MBDoE) method that enhances space exploration and reduces model prediction uncertainty by using a mapping of model prediction variance (G-optimality mapping). This explorative MBDoE (eMBDoE) named G-map eMBDoE is tested on two models of increasing complexity and compared against conventional factorial design of experiments, Latin Hypercube (LH) sampling and MBDoE methods. The results show that G-map eMBDoE is more efficient in exploring the experimental design space when compared to a standard MBDoE and outperforms classical design of experiments methods in terms of model prediction uncertainty reduction and parameters precision maximization
A role for Separase in telomere protection
Drosophila telomeres are elongated by transposition of specialized retroelements rather than telomerase activity and are assembled independently of the sequence. Fly telomeres are protected by the terminin complex that localizes and functions exclusively at telomeres and by non-terminin proteins that do not serve telomere-specific functions. We show that mutations in the Drosophila Separase encoding gene Sse lead not only to endoreduplication but also telomeric fusions (TFs), suggesting a role for Sse in telomere capping. We demonstrate that Separase binds terminin proteins and HP1, and that it is enriched at telomeres. Furthermore, we show that loss of Sse strongly reduces HP1 levels, and that HP1 overexpression in Sse mutants suppresses TFs, suggesting that TFs are caused by a HP1 diminution. Finally, we find that siRNA-induced depletion of ESPL1, the Sse human orthologue, causes telomere dysfunction and HP1 level reduction in primary fibroblasts, highlighting a conserved role of Separase in telomere protection
The Drosophila Citrate Lyase Is Required for Cell Division during Spermatogenesis
The Drosophila melanogaster DmATPCL gene encodes for the human ATP Citrate Lyase (ACL) ortholog, a metabolic enzyme that from citrate generates glucose-derived Acetyl-CoA, which fuels central biochemical reactions such as the synthesis of fatty acids, cholesterol and acetylcholine, and the acetylation of proteins and histones. We had previously reported that, although loss of Drosophila ATPCL reduced levels of Acetyl-CoA, unlike its human counterpart, it does not affect global histone acetylation and gene expression, suggesting that its role in histone acetylation is either partially redundant in Drosophila or compensated by alternative pathways. Here, we describe that depletion of DmATPCL affects spindle organization, cytokinesis, and fusome assembly during male meiosis, revealing an unanticipated role for DmATPCL during spermatogenesis. We also show that DmATPCL mutant meiotic phenotype is in part caused by a reduction of fatty acids, but not of triglycerides or cholesterol, indicating that DmATPCL-derived Acetyl-CoA is predominantly devoted to the biosynthesis of fatty acids during spermatogenesis. Collectively, our results unveil for the first time an involvement for DmATPCL in the regulation of meiotic cell division, which is likely conserved in human cells
The assessment of consumer sensitivity to animal welfare: An application of Rasch Model
The sensitivity has become a mass phenomenon, still in expansion. The European
Commission, during last decade, carried out several surveys on food quality and animal
welfare. This research, using data from a survey conducted on 320, respondents
and applying the Rasch model on 14 selected questions (items), wants to develop a
measure that appears representative of a latent variable defined as \u2018Sensitivity towards
Animal Welfare\u2019. The ability to measure the individual level of this \u2018Sensitivity\u2019
therefore represents an interesting and important result, especially if there are
correlations between this variable and other variables characterizing the opinions
and habits of individuals, both in general and in relation to consumer decisions
In vitro bactericidal activities of various extracts of saffron (Crocus sativus L.) stigmas from Torbat-e Heydarieh, Gonabad and Khorasan, Iran
Saffron is one of the most expensive spices in the world (20,000 €/kg) and this is due not only to the high demand for its various uses such as cooking, production of staining medicines, cosmetics etc., but also for the high costs of cultivation and production. Several studies have demonstrated that differences in saffron quality are mainly due to the methodology followed in the processing of stigmas, and environmental conditions independent of the origin. Some authors found phenotypic variations within cultivated saffron, but very limited genetic diversity. The reason for the very limited genetic diversity in cultivated saffron is explained by its asexual mode of reproduction (propagation). The aim of this study was to assess the antimicrobial activity of stigma saffron, which were tested against different bacteria strains. The results obtained from the antimicrobial activity study indicate that stigmas of C. sativus have some antimicrobial effect
Inhibition of Listeria monocytogenes by a formulation of selected dairy starter cultures and probiotics in an in vitro model
Three strains of lactic acid bacteria (LAB) and a commercial probiotic were selected to evaluate their in vitro activity towards Listeria monocytogenes. The strains Lactococcus lactis ssp. lactis, strain 340, L. lactis ssp. lactis, strain 16; Lactobacillus casei ssp. casei, strain 208 and Enterococcus faecium UBEF-41 were inoculated into skim milk and brain heart infusion broth (BHI) to get an initial Lactococcus: Lactobacillus: E. faecium UBEF-41 ratio of 2:1:1 and a concentration of approximately 7 log cfu mL−1 until challenge vs. pathogen. L. monocytogenes ATCC 7644 was also inoculated in same media to get approximately 4 log cfu mL−1. Growth curves in skim milk and BHI at 4, 10 and 30 °C, respectively were studied for: (i) LAB formulation; (ii) L. monocytogenes and (iii) LAB vs. L. monocytogenes. When challenged with LAB, at 30 °C in milk, L. monocytogenes was not detectable after day-3 and in BHI it decreased below log cfu mL−1 after day-5. At 10 and 4 °C, in both media, L. monocytogenes counts were always significantly lower (p < .001) than the counts of L. monocytogenes alone from day-2 for milk at 4 °C and BHI at 10 °C and from day-7 for BHI at 4 °C and milk at 10 °C. In conclusion, the proposed formulation was able to limit L. monocytogenes in vitro growth, even at refrigeration temperature
New trends in meat packaging
The term ‘packaging’ refers to the technological intervention aimed at the protection of food
from a variety of factors, which provokes the product detriment. Packaging is considered as one of
the most interesting technological aspects and a constantly evolving issue in food production.
This paper aims at the evaluation of the properties of packaging currently used in the meat
industry and analyses the advantages, the disadvantages and the microbiota involved. Packaging is
a coordinated system, which prepares the products for transportation, distribution, storage, marketing
and consumption. Even if several packaging alternatives are proposed, the common purpose is to
guarantee high standards, yet maintaining the required characteristics as long as possible. Meat is
a dynamic system with a limited shelf-life and the nutritional and sensory properties may change
during storage due to microbial activity and physical or chemical changes. Microbial spoilage,
for instance, determines an impact in meat, producing unattractive odours, flavours, discolouration,
gas and slime.EFSAam2021Paraclinical Science
West Nile virus transmission. results from the integrated surveillance system in Italy, 2008 to 2015
IIn Italy a national Plan for the surveillance of imported and autochthonous human vector-borne diseases (chikungunya, dengue, Zika virus disease and West Nile virus (WNV) disease) that integrates human and veterinary (animals and vectors) surveillance, is issued and revised annually according with the observed epidemiological changes. Here we describe results of the WNV integrated veterinary and human surveillance systems in Italy from 2008 to 2015. A real time data exchange protocol is in place between the surveillance systems to rapidly identify occurrence of human and animal cases and to define and update the map of affected areas i.e. provinces during the vector activity period from June to October. WNV continues to cause severe illnesses in Italy during every transmission season, albeit cases are sporadic and the epidemiology varies by virus lineage and geographic area. The integration of surveillance activities and a multidisciplinary approach made it possible and have been fundamental in supporting implementation of and/or strengthening preventive measures aimed at reducing the risk of transmission of WNV trough blood, tissues and organ donation and to implementing further measures for vector control
The Drosophila telomere-capping protein Verrocchio binds single-stranded DNA and protects telomeres from DNA damage response
Drosophila telomeres are sequence-independent structures maintained by transposition to chromosome ends of three specialized retroelements rather than by telomerase activity. Fly telomeres are protected by the terminin complex that includes the HOAP, HipHop, Moi and Ver proteins. These are fast evolving, non-conserved proteins that localize and function exclusively at telomeres, protecting them from fusion events. We have previously suggested that terminin is the functional analogue of shelterin, the multi-protein complex that protects human telomeres. Here, we use electrophoretic mobility shift assay (EMSA) and atomic force microscopy (AFM) to show that Ver preferentially binds single-stranded DNA (ssDNA) with no sequence specificity. We also show that Moi and Ver form a complex in vivo. Although these two proteins are mutually dependent for their localization at telomeres, Moi neither binds ssDNA nor facilitates Ver binding to ssDNA. Consistent with these results, we found that Ver-depleted telomeres form RPA and γH2AX foci, like the human telomeres lacking the ssDNA-binding POT1 protein. Collectively, our findings suggest that Drosophila telomeres possess a ssDNA overhang like the other eukaryotes, and that the terminin complex is architecturally and functionally similar to shelterin
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