An Advanced Colour Calibration Method for Fish Freshness Assessment: a Comparison Between Standard and Passive Refrigeration Modalities

Freshness represents a pivotal aspect in fish product for both security and quality. Its evaluation still represents the key factor driving the consumer’ choices. Fish appearance is affected by many different factors that demand the contribution of different disciplines to be understood: from the physical and optical properties to the slaughtering and post-slaughtering conditions. An innovative preservation system is represented by the Passive Refrigeration PRS? developed for the preservation and transport of perishable food products. Scientific methods for product freshness evaluation may be conveniently divided into two categories: sensorial and instrumental. In this study, an instrumental method of colour calibration and discrimination is proposed at pilot scale for automatic evaluation of gilthead seabream (Sparus aurata) freshness. We propose a non-destructive method based on the colorimetric imaging of the whole external body of seabreams to evaluate through multivariate partial least squares which approach the differences in the freshness preservation under four refrigeration modalities. The matrix of the independent variables is represented by RGB values for each pixel belonging to an extracted region of interest (129,633 values). The dependent variable is composed by two dummy variable corresponding to fresh (T₀) or non-fresh (T₂) individuals. T₁ individuals were used as external test. The results quantified significant colorimetric differences between fresh and non-fresh fish. All fish used to create the model (T₀ and T₂) were correctly classified as fresh or non-fresh, while external test individuals (T₁) were all classified as fresh. The proposed imaging method merges different image analysis techniques: (a) colorimetric calibration, (b) morphometric superimposition and (c) partial least square discriminant analysis modelling. This innovative and non-destructive approach allows the automatic assessment of fish freshness.     

An extended (fractal) Overlapping Crack Model to describe crushing size-scale effects in compression

The inherent microstructural disorder strongly influences the mechanical behaviour of heterogeneous materials such as concrete and rocks. Tensile and compression tests, in fact, evidenced a localization of strain and dissipated energy in the post-peak softening branch, with a consequent scale dependence of the stress–strain response. For this reason, the well-known Cohesive Crack Model and the recently proposed Overlapping Crack Model are useful tools for describing the size effects in tension and compression, respectively. In general, strain localization, damage and fracture, which are phenomena affecting the failure of concrete, are not rigorously interpretable in the framework of continuum mechanics. On the other hand, since the flaw and the aggregate distributions in quasibrittle materials are often self-similar (i.e. they look the same at different magnification levels), the microstructure may be correctly modelled by fractal sets. In this paper, the approach based on fractal geometry, that has profitably been applied for the tensile behaviour, is applied to obtain a fractal overlapping law from uniaxial compression tests. According to this approach, it is assumed that energy dissipation, stress and strain are not defined with respect to the canonical physical dimensions, though on fractal sets presenting noninteger physical dimensions. As a consequence, these classical parameters should be substituted by fractal quantities, which become the true material properties.     

Bisorbicillinoids Produced by the Fungus <Emphasis Type="Italic">Trichoderma citrinoviride</Emphasis> Affect Feeding Preference of the Aphid <Emphasis Type="Italic">Schizaphis graminum</Emphasis>

We report the effects of some bisorbicillinoids isolated from biomass of the fungus Trichoderma citrinoviride on settling and feeding preference of the aphid Schizaphis graminum. Purification of the fungal metabolites was carried out by a combination of column chromatography and thin-layer chromatography using direct and reverse phases. Chemical identification was performed by spectroscopic methods including nuclear magnetic resonance and mass spectrometry. The identified bisorbicillinoids appeared to be bislongiquinolide, its 16,17-dihydro derivative, trichodimerol, and dihydrotrichodimerol. A feeding preference test with alate morphs of S. graminum was used to identify the active fractions. Among the four bisorbicillinoids, dihydrotrichodimerol and bislongiquinolide influenced aphid feeding preference, restraining specimens from settling on leaves treated with metabolites. Taste neurons sensitive to these compounds, particularly to bislongiquinolide, were located on tarsi of the S. graminum alate morphs.     

Sinusoidal disturbance rejection in chaotic planar oscillators

The main goal of this paper is to design a compensator able to restore the nominal behavior of a planar system, which is rendered chaotic by an unmeasurable sinusoidal disturbance input. To reach such a goal, some instruments, taken from algebraic geometry, are used to estimate the unmeasurable disturbance from the time derivatives of the output of the system and of the control input. Copyright © 2015 John Wiley & Sons, Ltd.     

A PNA-array platform for the detection of hidden allergens in foodstuffs

A duplex PCR method was developed to simultaneously detect the presence of hazelnut and peanut in raw materials and commercial products. It was found to be able to specifically detect traces of the investigated products down to 50 pg of their target DNA.A PNA array device has been designed and implemented to be used in combination with the duplex PCR in order to investigate the presence of traces of potentially allergenic nuts in foodstuffs. A PNA probe for each target amplified by the duplex PCR was designed, synthesized and characterized. The PNA probes were then deposited on commercial slides in order to build a PNA array to be used for recognizing the PCR products; the concentration of the probes as function of the concentration of the target DNA, together with the specificity of the probes were investigated.The conditions optimized during the setting of the experiment were used to obtain the final version of the PNA array which was then used to test several commercially available foodstuffs claiming to contain or not to contain the targeted nuts.     

High Regio- and Stereoselective Multi-enzymatic Synthesis of All Phenylpropanolamine Stereoisomers from β-Methylstyrene

We present a one-pot cascade for the synthesis of phenylpropanolamines (PPAs) in high optical purities (er and dr up to >99.5 %) and analytical yields (up to 95 %) by using 1-phenylpropane-1,2-diols as key intermediates. This bioamination entails the combination of an alcohol dehydrogenase (ADH), an ω-transaminase (ωTA) and an alanine dehydrogenase to create a redox-neutral network, which harnesses the exquisite and complementary regio- and stereo-selectivities of the selected ADHs and ωTAs. The requisite 1-phenylpropane-1,2-diol intermediates were obtained from trans- or cis-β-methylstyrene by combining a styrene monooxygenase with epoxide hydrolases. Furthermore, in selected cases, the envisioned cascade enabled to obtain the structural isomer (1S,2R)-1-amino-1-phenylpropan-2-ol in high optical purity (er and dr >99.5 %). This is the first report on an enzymatic method that enables to obtain all of the four possible PPA stereoisomers in great enantio- and diastereo-selectivity.     

Digital twin of composite assembly manufacturing process

Industry is facing the management of geometrical deviations along the entire lifecycle of the product. It is helped by digital twin tools that may minimise the geometrical deviations from nominal of products. The new digital twin tools allow to manage geometrical variations through a set of steps fully related by modern information and communication technologies that establish a continuous and unambiguous flow of information among the different steps of this digital process along the whole product lifecycle. They are based on data coming from manufacturing, assembly and inspection. The available large data sets from manufacturing and inspection allow to develop new and more accurate simulation models that realistically consider form deviations and process signature, i.e. the pattern left by the manufacturing process on the produced part surfaces. The present work introduces a digital twin tool to support the lightweight design of assemblies in composite material. It establishes a continuous and unambiguous flow of variation information from the part design to assembly, passing through manufacturing by considering the manufacturing signature. It was applied to a case study and the obtained results agree with the experimental ones.     

Scouting around 1,2,3,4-Tetrahydrochromeno[3,2-c]pyridin-10-ones for Single- and Multitarget Ligands Directed towards Relevant Alzheimer's Targets

A number of 1,2,3,4-tetrahydrochromeno[3,2-c]pyridin-10-one derivatives have been synthesized and screened against different targets involved in the onset and progression of Alzheimer's disease (AD), such as acetyl- and butyrylcholinesterase (AChE and BChE), monoamine oxidases A and B (MAO A and B), aggregation of β-amyloid (Aβ) and reactive oxygen species (ROS) production. Derivatives 1 c , 3 b , 4 and 5 a showed multifaceted profiles of promising anti-AD features and returned well-balanced multitargeting inhibitory activities. Moreover, compound 1 f , a potent and selective human MAO B inhibitor (IC₅₀=0.89 μM), proved to be a safe neuroprotectant in a human neuroblastoma cell line (SH-SY5Y) by improving viability impaired by Aβ_1–42 and pro-oxidant insult. Furthermore, structure–activity relationships (SARs) and docking models were derived in order to assist further hit-to-lead optimization stage.     

Spectrum of clinicopathologic manifestations of arrhythmogenic right ventricular cardiomyopathy/dysplasia: a multicenter study

OBJECTIVES: The aim of the present investigation was to redefine the clinicopathologic profile of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC), with special reference to disease progression and left ventricular (LV) involvement. BACKGROUND: Long-term follow-up data from clinical studies indicate that ARVC is a progressive heart muscle disease that with time may lead to more diffuse right ventricular (RV) involvement and LV abnormalities and culminate in heart failure. METHODS: Forty-two patients (27 male, 15 female; 9 to 65 years old, mean [+/-SD] age 29.6 +/- 18) from six collaborative medical centers, with a pathologic diagnosis of ARVC at autopsy or heart transplantation, and with the whole heart available, were studied according to a specific clinicomorphologic protocol. RESULTS: Thirty-four patients died suddenly (16 during effort); 4 underwent heart transplantation; 2 died as a result of advanced heart failure; and 2 died of other causes. Sudden death was the first sign of disease in 12 patients; the other 30 had palpitations, with syncope in 11, heart failure in 8 and stroke in 3. Twenty-seven patients experienced ventricular arrhythmias (ventricular tachycardia in 17), and 5 received a pacemaker. Ten patients had isolated RV involvement (group A); the remaining 32 (76%) also had fibrofatty LV involvement that was observed histologically only in 15 (group B) and histologically and macroscopically in 17 (group C). Patients in group C were significantly older than those in groups A and B (39 +/- 15 years vs. 20 +/- 8.8 and 25 +/- 9.7 years, respectively), had significantly longer clinical follow-up (9.3 +/- 7.3 years vs. 1.2 +/- 2.1 and 3.4 +/- 2.2 years, respectively) and developed heart failure significantly more often (47% vs. 0 and 0, respectively). Patients in groups B and C had warning symptoms (80% and 87%, respectively, vs. 30%) and clinical ventricular arrhythmias (73% and 82%, respectively, vs. 20%) significantly more often than patients in group A. Hearts from patients in group C weighed significantly more than those from patients in groups A and B (500 +/- 150 g vs. 328 +/- 40 and 380 +/- 95 g, respectively), whereas hearts from both group B and C patients had severe RV thinning (87% and 71%, respectively, vs. 20%) and inflammatory infiltrates (73% and 88%, respectively, vs. 30%) significantly more often than those from group A patients. CONCLUSIONS: LV involvement was found in 76% of hearts with ARVC, was age dependent and was associated with clinical arrhythmic events, more severe cardiomegaly, inflammatory infiltrates and heart failure. ARVC can no longer be regarded as an isolated disease of the right ventricle.     

Occurrence and toxicity of Fusarium subglutinans from Peruvian maize

In a phase II clinical trial of 5-fluorouracil (5FU) plus N-(phosphonacetyl)-L-aspartate (PALA) therapy administration, a number of slowly developing clinical responses were observed. Because of this, a variety of immune parameters were sequentially studied in 21 patients on this trial. Of the 21 patients studied, 20 provided sufficient samples to compare baseline with subsequent values, 10 of the 20 patients responded to treatment. Responders and non-responders did not differ in any studied parameter at baseline. After 2 months of therapy, non-specific monocyte cytotoxicity (NSMC), antibody-dependent monocyte cytotoxicity (ADMC) and natural killer (NK) activity were higher in the entire study population, but these increases were not statistically significant. When responders and non-responders were evaluated separately, it was apparent that the trend was due solely to the changes observed in the responding patient population. When mean lysis values for each patient group were determined for each studied time point, it was possible to generate a mean area under the cytotoxicity/time curve (AUC) for each studied parameter. NSMC and ADMC did not differ in responders and non-responders. However, NK activity was significantly greater by mean AUC analysis (P = 0.006) in the responding group; NK activity was maintained in the responders, but decreased in non-responders. When lymphocyte and monocyte expression of the surface markers beta 2-microglobulin, HLA-DR, CD56, HNK-1, CD16 and interleukin-2 receptor were evaluated, there were no differences among responders and non-responders at baseline by mean AUC analysis or when comparing baseline with non-baseline values. It is concluded that although baseline immunological characteristics do not identify patients who are likely to respond to weekly 5FU and PALA, treatment is not associated with deleterious effects on the immune effector function parameters evaluated in this study, there being no effects on expression of a variety of associated cell-surface molecules.