An algorithm for the selection of high‐contrast color sets

Nominal color coding is the aesthetic and functional use of color to convey qualitative information in graphical environments. The specification of high‐contrast color sets is a fundamental step in this process. We formulate the color‐coding problem here as a combinatorial optimization problem on graphs and present an algorithm that performs well and does not require that the function used to code the similarity between colors be a distance function. © 1999 John Wiley & Sons, Inc. Col Res Appl, 24, 132–138, 1999     

TSC study of secondary dielectric relaxations in a polyepoxy matrix composite

Two thermal analysis techniques—Differential Scanning Calorimetry and Thermostimulated Current—have been used to characterize a mica/glass fiber-reinforced composite; the matrix is a novolac epoxy resin. The glass transition temperature of the composite as determined by DSC is 80°C. Below the glass transition temperature, two complex relaxation modes γ and β, respectively situated at −90 and −40°C, have been observed. The analysis of the fine structure shows that they are constituted of elementary processes characterized by relaxation times following compensation laws. Because the compensation temperature corresponding to the γ mode is located in the vicinity of the glass transition, it has been assigned to cooperative movements precursors of the glass transition. The mobile units might be the phenyl rings in the bisphenol A. Considering its dependence upon water content, the β mode has been related to the molecular mobility of bound water. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 135–139, 1997     

The effect of kaolin properties on their behaviour in ceramic processing as illustrated by a range of kaolins from the Santa Cruz and Chubut Provinces, Patagonia (Argentina)

The Patagonian kaolins offer a wide set of origin of deposits, composition, mineral processing and ceramic properties, giving a rare opportunity for investigating the interdependence of mineralogy, chemical composition, particle size distribution, texture, and surface activity with their technological behaviour in sanitaryware and porcelain stoneware production. Plasticity is strictly dependent on surface activity, < 2 μm fraction and expandable clay minerals; slip rheology is affected by soluble salts and expandable clay minerals, but also by high specific surface or tubular halloysite. Kaolinite/halloysite play an opposite role versus smectite/interstratified I/S in slip casting and tile pressing: the former allow faster casting rates, while the latter improve powder flowability and mechanical strength. Kaolinite and quartz are beneficial for drying behaviour while high surface activity or expandable clay minerals increase significantly drying sensitivity. Firing behaviour is mainly affected by minor components supplying “fluxing” (i.e. iron, alkali and alkaline-earth) oxides. A great deal of technological parameters seem to be reasonably predicted by the surface activity of clays and especially the Methylene Blue index, which is the most reliable, simple and economic method to predict and control the ceramic response of kaolins and ball clays.     

Blood Vessels: The Pathway Used by Schwann Cells to Colonize Nerve Conduits

The repair of severe nerve injuries requires an autograft or conduit to bridge the gap and avoid axon dispersion. Several conduits are used routinely, but their effectiveness is comparable to that of an autograft only for short gaps. Understanding nerve regeneration within short conduits could help improve their efficacy for longer gaps. Since Schwann cells are known to migrate on endothelial cells to colonize the “nerve bridge”, the new tissue spontaneously forming to connect the injured nerve stumps, here we aimed to investigate whether this migratory mechanism drives Schwann cells to also proceed within the nerve conduits used to repair large nerve gaps. Injured median nerves of adult female rats were repaired with 10 mm chitosan conduits and the regenerated nerves within conduits were analyzed at different time points using confocal imaging of sequential thick sections. Our data showed that the endothelial cells formed a dense capillary network used by Schwann cells to migrate from the two nerve stumps into the conduit. We concluded that angiogenesis played a key role in the nerve conduits, not only by supporting cell survival but also by providing a pathway for the migration of newly formed Schwann cells.     

Occurrence,Characterization, and Antimicrobial Susceptibility of Salmonella enterica in Slaughtered Pigs in Sardinia

The aim of this study was to determine Salmonella occurrence in slaughtered finishing pigs and piglets and in slaughterhouse environment in order to characterize the isolates with phenotypical (antimicrobial testing) and molecular (PFGE, MLVA) methods. Nine slaughterhouses located in Sardinia were visited. Six hundred and eight samples collected from 106 pigs and 108 environmental samples were collected and analyzed. Salmonella was isolated in 65 of 504 (12.9%) samples from finishing pigs, with an occurrence of 15.1% in colon content, 12.7% in lymph nodes and liver, and 11.1% in carcass surface samples. Salmonella was never detected in piglets. The combined results of serotyping and PFGE showed a possible self‐contamination in 71.5% of Salmonella positive carcasses of lymph nodes and/or colon content carriers, pointing out the role of healthy pigs for carcass contamination. A significantly higher (P < 0.05) occurrence was detected in finishing pigs of EC countries origin (23%) than in pigs of local farms (8%). Salmonella was also detected in 3.7% of environmental samples. The most prevalent serovar was S. Anatum, followed by S. Rissen, S. Derby, and monophasic S. Typhimurium. Resistance to at least 3 antimicrobial was observed in 97.1% of strains and 7 different patterns of multiple resistance were identified. The most common resistance was detected against sulphonamide compounds. A strict slaughterhouse application of hygiene standards is essential to control the risk of Salmonella contamination.     

Development and Preliminary Testing of Porcine Blood-Derived Endothelial-like Cells for Vascular Tissue Engineering Applications: Protocol Optimisation and Seeding of Decellularised Human Saphenous Veins

Functional endothelial cells (EC) are a critical interface between blood vessels and the thrombogenic flowing blood. Disruption of this layer can lead to early thrombosis, inflammation, vessel restenosis, and, following coronary (CABG) or peripheral (PABG) artery bypass graft surgery, vein graft failure. Blood-derived ECs have shown potential for vascular tissue engineering applications. Here, we show the development and preliminary testing of a method for deriving porcine endothelial-like cells from blood obtained under clinical conditions for use in translational research. The derived cells show cobblestone morphology and expression of EC markers, similar to those seen in isolated porcine aortic ECs (PAEC), and when exposed to increasing shear stress, they remain viable and show mRNA expression of EC markers similar to PAEC. In addition, we confirm the feasibility of seeding endothelial-like cells onto a decellularised human vein scaffold with approximately 90% lumen coverage at lower passages, and show that increasing cell passage results in reduced endothelial coverage.     

The Arrival of Gene Therapy for Patients with Hemophilia A

Historically, the standard of care for hemophilia A has been intravenous administration of exogenous factor VIII (FVIII), either as prophylaxis or episodically. The development of emicizumab, a humanized bispecific monoclonal antibody mimicking activated FVIII, was a subsequent advance in treatment. However, both exogenous FVIII and emicizumab require repeated and lifelong administration, negatively impacting patient quality of life. A recent breakthrough has been the development of gene therapy. This allows a single intravenous treatment that could result in long-term expression of FVIII, maintenance of steady-state plasma concentrations, and minimization (or possibly elimination) of bleeding episodes for the recipient’s lifetime. Several gene therapies have been assessed in clinical trials, with positive outcomes. Valoctocogene roxaparvovec (an adeno-associated viral 5-based therapy encoding human B domain-deleted FVIII) is expected to be the first approved gene therapy in European countries, including Italy, in 2022. Some novel challenges exist including refining patient selection criteria, managing patient expectations, further elucidation of the durability and variability of transgene expression and long-term safety, and the development of standardized ‘hub and spoke’ centers to optimize and monitor this innovative treatment. Gene therapy represents a paradigm shift, and may become a new reference standard for treating patients with hemophilia A.     

A parametric branch and bound approach to suboptimal explicit hybrid MPC

In this article we present a parametric branch and bound algorithm for computation of optimal and suboptimal solutions to parametric mixed-integer quadratic programs and parametric mixed-integer linear programs. The algorithm returns an optimal or suboptimal parametric solution with the level of suboptimality requested by the user. An interesting application of the proposed parametric branch and bound procedure is suboptimal explicit MPC for hybrid systems, where the introduced user-defined suboptimality tolerance reduces the storage requirements and the online computational effort, or even enables the computation of a suboptimal MPC controller in cases where the computation of the optimal MPC controller would be intractable. Moreover, stability of the system in closed loop with the suboptimal controller can be guaranteed a priori.     

Cytokine Pathways and Investigational Target Therapies in Hidradenitis Suppurativa

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease affecting areas with a high density of apocrine glands and characterized by subcutaneous nodules that may evolve into fistulas with pus secretion. Methods: The aim of this review is to investigate all current knowledge on cytokine regulation in the pathogenesis of HS. A systematic literature research using the words “cytokine”, “interleukin”, “pathway”, and “hidradenitis suppurativa” was performed in PubMed/Medline and Scopus/Embase databases. A search of the clinicaltrials.gov website for interventional recruiting and completed trials including the term “hidradenitis suppurativa” was also performed up to August 2020. We will discuss the pathogenetic role of various cytokines in HS and potential therapeutic targets for this debilitating disease. Results: The pathophysiology underlying this complex condition has not been clearly defined. An upregulation of various cytokines, such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-1, IL-17, IL-23, and other molecules seems to be related to this inflammatory condition. Various cells, such as lymphocytes T Helper 1 and 17 and keratinocytes seem to be involved in the genesis of this condition. Conclusions: Several future studies and clinical trials are necessary in order to have new knowledge about HS and to properly treat this complex condition.