Iron-based reversible adhesives: Effect of particles size on mechanical properties

A hot melt adhesive – mainly used for bonding plastic component in automotive field – was modified with different iron-based particles to give it a reversible behaviour. Mechanical and physical properties of these reversible adhesives were experimentally assessed in the work. The modified adhesives, coupled with electromagnetic induction, are able to guarantee separation of the joints without any damage to the substrates for recycling, reuse or repairing of components. Single lap joint specimens were prepared using epoxy/glass fibres substrates and tests were carried out on neat and modified adhesive with 5% weight of iron and iron oxide. Three different Fe particles size were tested: 450 µm, 60 µm and 1–6 µm. The particles size of iron oxide was 50 nm. Separation was studied using single lap joint specimens under electro-magnetic induction. Experimental results showed that the maximum peak load decreases when the average particles sizes increase. The peak loads of the smallest particles were equal to the ones of the pristine adhesive. The elongation of the adhesives increases when the adhesive is modified with both iron and iron oxide particles. Finally, experimental tests on single lap joints coupled with electro-magnetic induction showed that separation of the substrates is possible using iron oxide particles. Electro-magnetic tests conducted on particles alone, helped to understand that bigger particles are able to overcome the melting temperature of the adhesive but hot-melt adhesives modified with these particles are not able to reach the melting. These tests showed that the number of particles into the adhesive matrix is very important for this kind of tests. </jats:p

Design and Manufacturing Issues in the Development of Lightweight Solution for a Vehicle Frontal Bumper

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Debonding of adhesive joints by means of microwave and induction heating processes

In this work, an innovative technique for adhesive joint separation that combines the use of a hybrid-modified adhesive with microwave (MW) or induction heating (IH) [1-3] processes is presented. Graphene nanoplatelets (GnPs) and iron oxide particles were used to modify a thermoplastic adhesive, polyolefin hot-melt adhesive by mean of a twin-screw extruder. This thermoplastic adhesive, already used for bonding automotive applications, was modified with both iron oxide and GnPs in order to enhance the electrical properties and the sensitivity to MW and IH. The mechanical and electrical properties together with the sensitivity of the modified adhesives to microwave or induction heating processes are investigated. Single Lap Joint (SLJ) specimens were used to evaluate the mechanical properties of the pristine and the modified adhesive. The mechanical tests illustrate that the maximum loads of modified adhesives decrease slightly. Tests conducted with microwave and induction heating processes showed that these two systems are able to melt the modified adhesive. Thus, the separation of bonded joints is possible with both systems. The temperature increase of the induction heating system is found to be more rapid than the microwaves but the latter system is energetically more efficient. Scanning Electron Microscope (SEM) was used to measure the particle distribution and to evaluate the differences between the manual mixed mode and the tween extruder system as preliminary analysis

Fisurectomy and anoplasty with botulinum toxin injection in patients with chronic anal posterior fissure with hypertonia: a long-term evaluation

Chronic anal fissure\u2019s (CAF) etiopathogenesis remain unclear. CAF of the posterior commissure (CAPF) are often characterized by internal anal sphincter (IAS) hypertonia. The treatment of this disease aimed to reduce IAS hypertonia. Due to the high rate of anal incontinence after LIS, the employment of sphincter preserving surgical techniques associated to pharmacological sphincterotomy appears more sensible. The aim of our study is to evaluate the long-term results of fissurectomy and anoplasty with V\u2013Y cutaneous flap advancement associated to 30 UI of botulinum toxin injection for CAPF with IAS hypertonia. We enrolled 45 patients undergone to fissurectomy and anoplasty with V\u2013Y cutaneous flap advancement and 30 UI botulinum toxin injection. All patients were followed up for at least 5&nbsp;years after the surgical procedure, with evaluation of anal continence, recurrence rate and MRP (Maximum resting pressure), MSP (Maximum restricting pressure), USWA (Ultrasound wave activity). All patients healed within 40&nbsp;days after surgery. We observed 3 \u201cde novo\u201d post-operative anal incontinence cases, temporary and minor; the pre-operative ones have only temporary worsened after surgery. We reported 3 cases of recurrences, within 2&nbsp;years from surgery, all healed after conservative medical therapy. At 5&nbsp;year follow-up post-operative manometric findings were similar to those of healthy subjects. At 5&nbsp;years after the surgical procedure, we achieved good results, and these evidences show that surgical section of the IAS is not at all necessary for the healing process of the CAPF

The Ferroxidase Hephaestin in Lung Cancer: Pathological Significance and Prognostic Value

Hephaestin (HEPH) belongs to a group of exocytoplasmic ferroxidases which contribute to cellular iron homeostasis by favouring its export. Down-regulation of HEPH expression, possibly by stimulating cell proliferation due to an increase in iron availability, has shown to correlate with poor survival in breast cancer. The lung is particularly sensitive to iron-induced oxidative stress, given the high oxygen tension present, however, HEPH distribution in lung cancer and its influence on prognosis have not been investigated yet. In this study we explored the prognostic value of HEPH and its expression pattern in the most prevalent histotypes of lung cancers, namely lung adenocarcinoma and lung squamous cell carcinoma. In silico analyses, based on UALCAN, Gene Expression Profiling Interactive Analysis (GEPIA) and Kaplan–Meier plotter bioinformatics, revealed a significant correlation between higher levels of HEPH expression and favorable prognosis, in both cancer histotypes. Moreover, TIMER web platform showed a statistically significant association between HEPH expression and cell elements belonging to the tumor microenvironment identified as endothelial cells and a subpopulation of cancer-associated fibroblasts, further confirmed by double immunohistochemical labeling with cell type specific markers. Taken together, these data shed a light on the complex mechanisms of local iron handling lung cancer can exploit to support tumorigenesis

Yeast biota of naturally fermented black olives in different brines made from cv. Gemlik grown in various districts of the Cukurova region of Turkey

In this study, the yeast microbiota of naturally fermented black olives made from cv. Gemlik, grown in three different districts of the Çukurova region of Turkey, were investigated. Fermentations were conducted for 180 days in three different brines, including NaCl 10% w/v, NaCl 8% w/v and NaCl 8% w/v added with glucose 0.5%. In total, 223 yeasts were isolated and then identified by PCR–RFLP analysis of the 5.8S ITS rRNA region and sequence information for the D1/D2 domains of the 26S rRNA gene. A broad range of yeast biodiversity was identified, including eight genera and nine species. Candida boidinii (41%), Wickerhamomyces anomalus (32%) and Saccharomyces sp. (18%) were predominant yeasts throughout the fermentations. To a lesser extent, the other species, Candida aaseri, Meyerozyma sp., Zygoascus hellenicus, Pichia kudriavzevii, Schwanniomyces etchellsii and Candida atlantica were also members of the olive-fermenting microbiota. In Tarsus and Bahçe districts C. boidinii and in Serinyol district Saccharomyces sp. were the most frequently identified species. W. anomalus was the most frequently isolated species (by 48% of total yeasts) in NaCl 10% brines. C. boidinii was the most dominant species in the brines, including NaCl 8% and NaCl 8% + glucose 0.5%, with frequencies of 42% and 61%, respectively. At the end of the 180 days of fermentation, total acidity values of the brines were in the range 1.04–8.1 g/l lactic acid. Copyright © 2016 John Wiley & Sons, Ltd

Prognostic Implications of the Complement Protein C1q in Gliomas

The contribution of the complement system in the pathophysiology of brain cancers has been recently considered in light of its well-known involvement in carcinogenesis. Complement system represents an important component of the inflammatory response, which acts as a functional bridge between the innate and adaptive immune response. C1q, the first recognition subcomponent of the complement classical pathway, has recently been shown to be involved in a range of pathophysiological functions that are not dependent on complement activation. C1q is expressed in the microenvironment of various types of human tumors, including melanoma, prostate, mesothelioma, and ovarian cancers, where it can exert a protective or a harmful effect on cancer progression. Despite local synthesis of C1q in the central nervous system, the involvement of C1q in glioma pathogenesis has been poorly investigated. We, therefore, performed a bioinformatics analysis, using Oncomine dataset and UALCAN database in order to assess whether the expression of the genes encoding for the three chains of C1q (C1qA, C1qB, and C1qC) could serve as a potential prognostic marker for gliomas. The obtained results were then validated using an independent glioma cohort from the Chinese Glioma Genome Atlas datasets. Our bioinformatics analysis, coupled with immunohistochemistry and fluorescence microscopy, appears to suggest a positive correlation between higher levels of C1q expression and unfavorable prognosis in a diverse grade of gliomas