812 research outputs found

    Use of xanthan gum and calcium ascorbate to prolong cv. Butirra pear slices shelf life during storage

    Get PDF
    After cut, pear fruit (Pyrus communis L.) during shelf life can be subjected to color and flavor changes. To maintain flesh colour and firmness, different technologies could be employed during shelf life, such as chemical, physical and edible coating treatments. In the present study, the effects of two edible coating formulations containing xanthan gum and calcium ascorbate on fresh­cut pear fruit were investigated. After harvest, 200 fruits were cut and coated with Xanthan Gum (XAN) and distilled water or Xanthan gum + Calcium Ascorbate (ASC), respectively, while control (CTR) pear fruit slices were soaked in distilled water and lastly packed in polyethylene terephthalate (PET) packages sealed with a composite film (PP­PET). All samples were stored at 5±0.5°C with RH 90% for 10 days. Measurements were carried out at 3, 5, 7 and 10 days of storage evaluating visual quality score, browning index, color, total solid soluble content (TSS), flavor, ascorbic acid content and total phenols content. The results showed that ASC treatment was the most efficient treatment in terms of color changes, ascorbic acid content, visual quality score and browning index, until the 7th day of storage. Moreover, (ASC) treatment reported lower mean values in terms of taste and flavor score if compared to CTR and XAN treatments. Untreated pear slices (CTR) kept good values concerning flavor score until the 3rd day of storage while on the 5th and 7th day off­flavor values were the same as treated samples

    Posidonia Oceanica And Green Tea Extract As Active Agents For Shelf Life Extension Of Fresh Cut Peach

    Get PDF
    Nowadays the reduction of food waste and the availability of food all over the world areas are priority keys for society. In this context, the shelf life extension of fresh products in a sustainable way may represent one of the main goals. The aim of the present research work was to extend the shelf life of fresh cut peach slices by using extracts of Posidonia oceanica (POS) and green tea (GT), and compared to the control. Total polyphenols content was assessed by Folin-Ciocalteu method and the antioxidant capacity by DPPH (2,2-Diphenyl-1-Picrylhydrazyl) assay. Antimicrobial activity of the two extracts was initially carried out in vitro by determining the Minimal Inhibitory Concentration (MIC) against Escherichia coli, Listeria innocua, Pseudomonas putida, Staphylococcus aureus, Saccharomyces cerevisiae, Aspergillus niger and Penicillium chrysogenum. The two extracts in vivo on peach slices by dipping were applied (only water for the control), than, slices were placed into low-density polyethylene (LDPE) bag and stored at 3 ± 1°C for up to 7 days. Microbiological analyses, color (L*,a*,b*), total soluble solid (TSS) and titratable acidity (TA) on peach slices were carried out every 3 days. POS showed the highest polyphenols content (615±45 mg Gallic Acid Equivalent/g – mg GAE/g) while GT 526 ± 28 mg GAE/g. The values of EC50, for POS, was 72.42 ± 22.90 mg/L, while for GT 3.80 ± 0.11 mg/L. Trials in vitro showed MIC values of above 2 g/L for POS and above 1 g/L in GT mainly against Gram positive bacteria. POS was also found to lead a growth delay in the case of fungi, approximately 60 h compared to the control. Results related to the Total Aerobic (TAC) and yeasts and moulds (Y&M) counts highlighted that peach slices dipped with POS maintained in the first 5 days of storage the microbiota at lower or analogous levels than those found at t0 (1.80 ± 0.09 log cfu/g respect 2.30 ± 0.11 log cfu/g and 1.80 ± 0.05 log cfu/g respect 1.70 ± 0.03 log cfu/g of the control, respectively for TAC and Y&M). Regarding pomological analysis, after seven days, lightness of the peach slices decreased 28% in POS, 24% in GT and 35% in control. During shelf life TSS increased 8% in the control, 2% in POS and remained unchanged in GT, after seven days. At the same time, TA decreased 30% in POS, 20% in GT treatment and 63% in the control. During the experiment TSS increased in all treatments, more rapidly in the control; meanwhile the TA decreased slowly in treated samples compared to the control. Concluding, Posidonia oceanica and green tea extracts were found able to delay the colour and pomological parameters decay, maintaining a good fruit quality during shelf life. Data already showed evidence a better performance of the Posidonia extract, limiting the growth of microorganisms responsible for fresh fruit deterioration

    Cerebellum and neurodegenerative diseases: Beyond conventional magnetic resonance imaging

    Get PDF
    The cerebellum plays a key role in movement control and in cognition and cerebellar involvement is described in several neurodegenerative diseases. While conventional magnetic resonance imaging (MRI) is widely used for brain and cerebellar morphologic evaluation, advanced MRI techniques allow the investigation of cerebellar microstructural and functional characteristics. Volumetry, voxel-based morphometry, diffusion MRI based fiber tractography, resting state and task related functional MRI, perfusion, and proton MR spectroscopy are among the most common techniques applied to the study of cerebellum. In the present review, after providing a brief description of each technique's advantages and limitations, we focus on their application to the study of cerebellar injury in major neurodegenerative diseases, such as multiple sclerosis, Parkinson's and Alzheimer's disease and hereditary ataxia. A brief introduction to the pathological substrate of cerebellar involvement is provided for each disease, followed by the review of MRI studies exploring structural and functional cerebellar abnormalities and by a discussion of the clinical relevance of MRI measures of cerebellar damage in terms of both clinical status and cognitive performance

    Evaluation of the antioxidant/antimicrobial performance of Posidonia oceanica in comparison with three commercial natural extracts and as a treatment on fresh-cut peaches (Prunus persica Batsch)

    Get PDF
    This research aimed at extending the choice of natural antimicrobials/antioxidants for food applications. Four plant extracts, Posidonia oceanica (PO), Green Tea (GT), Grape seeds (GS) and Grape skin (GK), were analyzed to determine their total phenolic content, antioxidant activity and in vitro antimicrobial performance. PO extract showed the highest total phenolic content (711 mg gallic acid/g extract) and antifungal activity against Aspergillus niger and Penicillium chrysogenum. The highest antioxidant (3.81 mg/L EC50) and antibacterial activities (bactericidal against Gram positives and bacteriostatic against Gram negatives) were found for GT extract. The best performing extracts (PO and GT) were applied by dipping on peach slices in storage trials. Microbiological and pomological parameters were evaluated during 7 d storage. Total aerobic count, Pseudomonas as well as yeasts and moulds populations, were reduced by about 0.5 log cfu/g, mainly up to 5 d in all treated samples compared to the control. Total soluble solids, titratable acidity and colour (L*a*b*) changes were also delayed in treated fruit

    Autonomic function in amnestic and non-amnestic mild cognitive impairment : spectral heart rate variability analysis provides evidence for a brain–heart axis

    Get PDF
    Mild cognitive impairment (MCI) is a heterogeneous syndrome with two main clinical subtypes, amnestic (aMCI) and non-amnestic (naMCI). The analysis of heart rate variability (HRV) is a tool to assess autonomic function. Cognitive and autonomic processes are linked via the central autonomic network. Autonomic dysfunction entails several adverse outcomes. However, very few studies have investigated autonomic function in MCI and none have considered MCI subtypes or the relationship of HRV indices with different cognitive domains and structural brain damage. We assessed autonomic function during an active orthostatic challenge in 253 oupatients aged\u2009 65\u200965, [n\u2009=\u200982 aMCI, n\u2009=\u200993 naMCI, n\u2009=\u200978 cognitively normal (CN), neuropsychologically tested] with power spectral analysis of HRV. We used visual rating scales to grade cerebrovascular burden and hippocampal/insular atrophy (HA/IA) on neuroimaging. Only aMCI showed a blunted response to orthostasis. Postural changes in normalised low frequency (LF) power and in the LF to high frequency ratio correlated with a memory test (positively) and HA/IA (negatively) in aMCI, and with attention/executive function tests (negatively) and cerebrovascular burden (positively) in naMCI. These results substantiate the view that the ANS is differentially impaired in aMCI and naMCI, consistently with the neuroanatomic substrate of Alzheimer's and small-vessel subcortical ischaemic disease

    A composite measure to explore visual disability in primary progressive multiple sclerosis

    Get PDF
    Background: Optical coherence tomography (OCT) and magnetic resonance imaging (MRI) can provide complementary information on visual system damage in multiple sclerosis (MS). Objectives: The objective of this paper is to determine whether a composite OCT/MRI score, reflecting cumulative damage along the entire visual pathway, can predict visual deficits in primary progressive multiple sclerosis (PPMS). Methods: Twenty-five PPMS patients and 20 age-matched controls underwent neuro-ophthalmologic evaluation, spectral-domain OCT, and 3T brain MRI. Differences between groups were assessed by univariate general linear model and principal component analysis (PCA) grouped instrumental variables into main components. Linear regression analysis was used to assess the relationship between low-contrast visual acuity (LCVA), OCT/MRI-derived metrics and PCA-derived composite scores. Results: PCA identified four main components explaining 80.69% of data variance. Considering each variable independently, LCVA 1.25% was significantly predicted by ganglion cell-inner plexiform layer (GCIPL) thickness, thalamic volume and optic radiation (OR) lesion volume (adjusted R2 0.328, p = 0.00004; adjusted R2 0.187, p = 0.002 and adjusted R2 0.180, p = 0.002). The PCA composite score of global visual pathway damage independently predicted both LCVA 1.25% (adjusted R2 value 0.361, p = 0.00001) and LCVA 2.50% (adjusted R2 value 0.323, p = 0.00003). Conclusion: A multiparametric score represents a more comprehensive and effective tool to explain visual disability than a single instrumental metric in PPMS

    Modeling Dynamic Interaction in Virtual Environments and the Evaluation of Dynamic Virtual Fixtures

    Get PDF
    Virtual reality (VR) is a technology covering a large field of applications among which are sports and video games. In both gaming and sporting VR applications, interaction techniques involve specific gestures such as catching or striking. However, such dynamic gestures are not currently being recognized as elementary task primitives, and have therefore not been investigated as such. In this paper, we propose a framework for the analysis of interaction in dynamic virtual environments (DVEs). This framework is based on three dynamic interaction primitives (DIPs) that are common to many sporting activities: catching, throwing, and striking. For each of these primitives, an original modeling approach is proposed. Furthermore, we introduce and formalize the concept of dynamic virtual fixtures (DVFs). These fixtures aim to assist the user in tasks involving interaction with moving objects or with objects to be set in movement. Two experiments have been carried out to investigate the influence of different DVFs on human performance in the context of ball catching and archery. The results reveal a significant positive effect of the DVFs, and that DVFs could be either classified as “performance-assisted” or “learning-assisted.

    A Better Characterization of Spinal Cord Damage in Multiple Sclerosis: A Diffusional Kurtosis Imaging Study

    Get PDF
    BACKGROUND AND PURPOSE: The spinal cord is a site of predilection for MS lesions. While diffusion tensor imaging is useful for the study of anisotropic systems such as WM tracts, it is of more limited utility in tissues with more isotropic microstructures (on the length scales studied with diffusion MR imaging) such as gray matter. In contrast, diffusional kurtosis imaging, which measures both Gaussian and non-Gaussian properties of water diffusion, provides more biomarkers of both anisotropic and isotropic structural changes. The aim of this study was to investigate the cervical spinal cord of patients with MS and to characterize lesional and normal-appearing gray matter and WM damage by using diffusional kurtosis imaging. MATERIALS AND METHODS: Nineteen patients (13 women, mean age = 41.1 ± 10.7 years) and 16 controls (7 women, mean age = 35.6 ± 11.2-years) underwent MR imaging of the cervical spinal cord on a 3T scanner (T2 TSE, T1 magnetization-prepared rapid acquisition of gradient echo, diffusional kurtosis imaging, T2 fast low-angle shot). Fractional anisotropy, mean diffusivity, and mean kurtosis were measured on the whole cord and in normal-appearing gray matter and WM. RESULTS: Spinal cord T2-hyperintense lesions were identified in 18 patients. Whole spinal cord fractional anisotropy and mean kurtosis ( P = .0009, P = .003), WM fractional anisotropy ( P = .01), and gray matter mean kurtosis ( P = .006) were significantly decreased, and whole spinal cord mean diffusivity ( P = .009) was increased in patients compared with controls. Mean spinal cord area was significantly lower in patients ( P = .04). CONCLUSIONS: Diffusional kurtosis imaging of the spinal cord can provide a more comprehensive characterization of lesions and normal-appearing WM and gray matter damage in patients with MS. Diffusional kurtosis imaging can provide additional and complementary information to DTI on spinal cord pathology

    Relationship between retinal inner nuclear layer, age, and disease activity in progressive MS

    Get PDF
    Objective: To investigate whether inner nuclear layer (INL) thickness as assessed with optical coherence tomography differs between patients with progressive MS (P-MS) according to age and disease activity. Methods: In this retrospective longitudinal analysis, differences in terms of peripapillary retinal nerve fiber layer (pRNFL), ganglion cell layer + inner plexiform layer (GCIPL), INL and T1/T2 lesion volumes (T1LV/T2LV) were assessed between 84 patients with P-MS and 36 sex- and age-matched healthy controls (HCs) and between patients stratified according to age (cut-off: 51 years) and evidence of clinical/MRI activity in the previous 12 months RESULTS: pRNFL and GCIPL thickness were significantly lower in patients with P-MS than in HCs (p = 0.003 and p < 0.0001, respectively). INL was significantly thicker in patients aged < 51 years compared to the older ones and HCs (38.2 vs 36.5 and 36.7 ÎĽm; p = 0.038 and p = 0.04, respectively) and in those who presented MRI activity (new T2/gadolinium-enhancing lesions) in the previous 12 months compared to the ones who did not and HCs (39.5 vs 36.4 and 36.7 ÎĽm; p = 0.003 and p = 0.008, respectively). Recent MRI activity was significantly predicted by greater INL thickness (Nagelkerke R2 0.36, p = 0.001). Conclusions: INL thickness was higher in younger patients with P-MS with recent MRI activity, a criterion used in previous studies to identify a specific subset of patients with P-MS who best responded to disease-modifying treatment. If this finding is confirmed, we suggest that INL thickness might be a useful tool in stratification of patients with P-MS for current and experimental treatment choice

    Food quality and nutraceutical value of nine cultivars of mango (Mangifera indica L.) fruits grown in Mediterranean subtropical environment

    Get PDF
    Mango (Mangifera indica L.) quality is strongly influenced by genotype but individuating the most appropriate harvesting time is essential to obtain high quality fruits. In this trial we studied the influences of the ripening stage at harvest (mature-ripe or green-ripe) on quality of ready to eat mango fruits from nine cultivars (Carrie, Keitt, Glenn, Manzanillo, Maya, Rosa, Osteen, Tommy Atkins and Kensington Pride) grown in the Mediterranean subtropical climate through physicochemical, nutraceutical, and sensory analysis. Our results show a large variability among the different observed genotypes and in dependence of the ripening stage at harvest. With the exception of Rosa, mature-ripe fruits are well-colored, sweet and aromatic, and better suited for short supply chains. On the other hand, post-harvest ripened fruits are firmer, frequently (Carrie, Glenn, Keitt, Manzanillo, Maya) possess interesting nutraceutical value and, in the case of Glenn, Maya, Osteen, and Kensington Pride, they can reach market standard quality
    • …
    corecore