Long-range interactions in 1D heterogeneous solids with uncertainty

In this paper, the authors aim to analyze the response of a one-dimensional non-local elastic solid with uncertain Young's modulus. The non-local effects are represented as long-range central body forces between non-adjacent volume elements. Following a non-probabilistic approach, the fluctuating elastic modulus of the material is modeled as an interval field. The analysis is conducted resorting to a novel formulation that confines the overestimation effect involved in interval models. Approximate closed-form expressions are derived for the bounds of the interval displacement fiel

One-dimensional heterogeneous solids with uncertain elastic modulus in presence of long-range interactions: Interval versus stochastic analysis

The analysis of one-dimensional non-local elastic solids with uncertain Young's modulus is addressed. Non-local effects are represented as long-range central body forces between non-adjacent volume elements. For comparison purpose, the fluctuating elastic modulus of the material is modeled following both a probabilistic and a non-probabilistic approach. To this aim, a novel definition of the interval field concept, able to limit the overestimation affecting ordinary interval analysis, is introduced. Approximate closed-form expressions are derived for the bounds of the interval displacement field as well as for the mean-value and variance of the stochastic respons

PLEROCERCOID GYMNORHYNCHUS (CESTODA: TRYPANORHYNCHA) IN LEPIDOPUS CAUDATUS: INTERFERENCE ON TMA-N AND TVB-N DETERMINATION

Total Volatile Basic Nitrogen (TVB-N) and Trimethylamine Nitrogen (TMA-N) are the most important freshness indicators in fish. The present report demonstrates that the Gymnorhynchus gigas plerocercoid may interfere on TVBN and TMA-N determination. The study was carried-out on 101 samples: 37 Mp (muscle portions around the parasite), 32 P (larvae of Gymnorynchus gigas extracted from muscle) and 32 Mnp (muscle portions parasite-free), obtained from 10 specimens of Lepidopus caudatus kept at several temperature for different time. The TVB-N and TMA-N contents of each sample were measured using the Conway microdiffusion method. Statistically significant differences (p < 0.05) between Mp and Mnp for TMA-N were found from 24h of storage at 4 and 15°C. No significant differences (p < 0.05) between Mp and Mnp for TVB-N were observed from 48h of storage at 4 and 15°C. TVB-N and TMA-N content was variable in larvae

Cooking pasta with Lie groups

We extend the (gauged) Skyrme model to the case in which the global isospin group (which usually is taken to be SU(N)) is a generic compact connected Lie group G. We analyze the corresponding field equations in (3+1) dimensions from a group theory point of view. Several solutions can be constructed analytically and are determined by the embeddings of three dimensional simple Lie groups into G, in a generic irreducible representation. These solutions represent the so-called nuclear pasta state configurations of nuclear matter at low energy. We employ the Dynkin explicit classification of all three dimensional Lie subgroups of exceptional Lie group to classify all such solutions in the case G is an exceptional simple Lie group, and give all ingredients to construct them explicitly. As an example, we construct the explicit solutions for G=G2. We then extend our ansatz to include the minimal coupling of the Skyrme field to a U(1) gauge field. We extend the definition of the topological charge to this case and then concentrate our attention to the electromagnetic case. After imposing a \u201cfree force condition\u201d on the gauge field, the complete set of coupled field equations corresponding to the gauged Skyrme model minimally coupled to an Abelian gauge field is reduced to just one linear ODE keeping alive the topological charge. We discuss the cases in which such ODE belongs to the (Whittaker-)Hill and Mathieu types

A new approach to predict the fish fillet shelf-life in presence of natural preservative agents

Three data sets concerning the behaviour of spoilage flora of fillets treated with natural preservative substances (NPS) were used to construct a new kind of mathematical predictive model. This model, unlike other ones, allows expressing the antibacterial effect of the NPS separately from the prediction of the growth rate. This approach, based on the introduction of a parameter into the predictive primary model, produced a good fitting of observed data and allowed characterising quantitatively the increase of shelf-life of fillets

Injectable xyloglucan hydrogels incorporating spheroids of adipose stem cells for bone and cartilage regeneration

Cartilage or bone regeneration approaches based on the direct injection of mesenchymal stem cells (MSCs) at the lesion site encounter several challenges, related to uncontrolled cell spreading and differentiation, reduced cell viability and poor engrafting. This work presents a simple and versatile strategy based on the synergic combination of in-situ forming hydrogels and spheroids of adipose stem cells (SASCs) with great potential for minimally invasive regenerative interventions aimed to threat bone and cartilage defects. Aqueous dispersions of partially degalactosylated xyloglucan (dXG) are mixed with SASCs derived from liposuction and either a chondroinductive or an osteoinductive medium. The dispersions rapidly set into hydrogels when temperature is brought to 37 °C. The physico-chemical and mechanical properties of the hydrogels are controlled by polymer concentration. The hydrogels, during 21 day incubation at 37 °C, undergo significant structural rearrangements that support cell proliferation and spreading. In formulations containing 1%w dXG cell viability increases up to 300% for SASCs-derived osteoblasts and up to 1000% for SASCs-derived chondrocytes if compared with control 2D cultures. The successful differentiation into the target cells is supported by the expression of lineage-specific genes. Cell-cell and cell-matrix interactions are also investigated. All formulations resulted injectable, and the incorporated cells are fully viable after injection

NETME: on-the-fly knowledge network construction from biomedical literature

Background: The rapidly increasing biological literature is a key resource to automatically extract and gain knowledge concerning biological elements and their relations. Knowledge Networks are helpful tools in the context of biological knowledge discovery and modeling. Results: We introduce a novel system called NETME, which, starting from a set of full-texts obtained from PubMed, through an easy-to-use web interface, interactively extracts biological elements from ontological databases and then synthesizes a network inferring relations among such elements. The results clearly show that our tool is capable of inferring comprehensive and reliable biological networks

Hydrogel scaffolds based on k-Carrageenan/xyloglucan blends to host spheroids from human adipose stem cells

Hydrogels are water-swollen networks of hydrophilic polymer. They can be fabricated in various shapes and swell in water or aqueous solutions maintaining their original shape or undergo progressive erosion; can exibit large volume phase transitions with the change of one environmental parameter (stimuli-responsivness), shock absorption and low sliding friction properties (1). The morphology and mechanical properties of hydrogels are strongly affected by the network composition, the nature and degree of crosslinking and the degree of swelling. Indeed, when hydrogels are designed as scaffolds for human tissues remodeling, they must have sufficient mechanical integrity to provide support to the cells from the time of implantation to the completion of the process. The large amount of water present in the hydrogels and its microscopic pores interconnectivity allows transportation of nutrients, oxygen and metabolites, that ensures cells viability, and permits cells migration and scaffold colonization. The polymeric network can immobilize biomolecules that may affect cells growth or differentiation, control drug release profiles and enzymatic degradation (2,3). The combination of two hydrogelforming polymers with different chemistries and crosslinking densities can be used to tailor the morphology, mechanical strength and toughness of the scaffold to meet specific requirements (1). This work investigates the physico-chemical, morphological and mechanical properties of hydrogels formed by the blend of two polysaccharides, k-Carrageenan (k-C) and Degalactosylated Xyloglucan (Deg-XG) undergoing salt-induced and temperature-induced solgel transition, respectively. It also studies the compatibility of the two biopolymers with spheroids from adipose-derived stem cells (S-ASCs) in the prospect of developing instructive scaffolds for use in regenerative medicine

Hydrogel scaffolds blends to host Spheroids from human adipose stem cells

INTRODUCTION Adipose stem cells represent a reliable source of stem cells for their widely demonstrated potential in regenerative medicine and tissue engineering applications. New recent insights show that 3D models may properly mimic the native tissue properties; in fact Spheroids from Adipose derived Stem Cells (S-ASCs) displayed enhanced regenerative abilities if compared to 2D models. Stem cell therapy success is determined by "cell-quality" thus the involvement of stress signals and cellular aging need to be deeply investigated. The development of 3D cell-laden hydrogels has enabled to mimic the peculiar scenario of a native tissue. We studied SASCs-cell quality and tested their viability and differentiation abilities in new hydrogels. METHODS S-ASCs were obtained from liposuction of healthy patients. Analysis of aging, telomeric length and stress-oxidative genes was performed through Real-Time PCR. Physico-chemical, morphological and mechanical properties of k-Carrageenan (k-C, 2%w) and degalactosylated xyloglucan (Deg-XG, 2%w) hydrogels were defined. S-ASCs compatibility with hydrogels was evaluated by viability test and mesenchymal differentiation abilities. RESULTS Gene expression of genes linked with stemness, senescence and stress-oxidative was evaluated and correlated with SASCs-cell quality. Indeed, aging-related p16INK4a mRNA is downregulated while anti-aging Sirtuin1 is upregulated in 3D-SASCs. Furthermore, vegetal-origin hydrogels have guaranteed an optimal environment for S-ASCs in stemness and mesenchymal differentiation conditions. CONCLUSION Bio-instructive scaffolds are critical for exploiting stem cells therapeutic potential in tissue engineering. This study provides a versatile approach to investigate the interactions between cells in controlled settings, opening up novel 3D in vitro approaches to mimic the tissues complexity

Moringa oleifera leaf powder as functional additive in cookies to protect sh-sy5y cells

The aim of this work is the evaluation of the addition of Moringa leaf powder (MLP) in cookies in terms of antioxidant properties, dough processability and sensorial properties of the cookies. The total content of biophenols and flavonoids in MLP was detected and the identification of the bioactive molecules was performed by HPLC-ESI-TOF-MS measurements, before and after oven treatment at 180◦C for 20 min. After a preliminary evaluation of the MLP water soluble fraction (MLPsf) cytotoxicity, its protective effect against an oxidative injury induced in the SH-SY5Y cells was assessed. Data evidence that the bioactive molecules present in MLPsf are effective in preventing ROS production and in protecting neuronal cells against oxidative stress. Prototypes of cookies containing MLP in different concentrations were then produced and evaluated by a consumer panel. Selected doughs containing MLP were analysed to determine the total content of biophenols in the cookies after baking and their enrichment in terms of valuable chemical elements. The influence of MLP on the viscoelastic behaviour and morphology of the doughs was also assessed. Finally, the potential role in counteracting the insurgence of not treatable neurodegenerative pathologies of two main MLP components, glucomoringin and kaempferol derivatives, present also after the thermal treatment, was discussed