La TPM e la gestione della manutenzione: problematiche e miglioramenti nell'implementazione di un sistema di manutenzione periodica.

Questa tesi nasce da un periodo di stage di 6 mesi svolto presso il reparto di converting della Procter&Gamble Italia, nello stabilimento di Lucca. Il lavoro svolto ha riguardato la creazione di un sistema di manutenzione periodica per l’implementazione dello Step 4 del pilastro di Progressive Maintenance della TPM, l’ottimizzazione dell’attuale sistema di manutenzione e la sua integrazione con il sistema informativo usato per la sua gestione (Sap), nonché con gli standard IWS applicati in P&G. Per raggiungere gli obiettivi sopra citati si è intervenuti nelle seguenti aree: miglioramento e aggiornamento del piano di manutenzione periodica, studio dei giusti intervalli, riduzione del down time delle macchine, intervenendo sull’MTTR e sulle attività di preparazione dei lavori, riduzione dell’’effort. Le attività principali sviluppate sono: inserimento di nuovi lavori nel piano di manutenzione periodica, riduzione dell’MTTR di lavori di manutenzione critici, miglioramento dei DMS di Planning&Scheduling e di Shut-down Maintenance, sviluppo delle procedure di manutenzione e gestione del sistema tramite il supporto di Sap PM, attraverso la creazione delle Task List. Infine sono stati costruiti due modelli di step 4 da riapplicare a tutto il converting, di cui uno riguardante la riduzione dell’MTTR di un intervento di manutenzione complesso e l’altro relativo ad un’analisi di criticità, tipo Magec, del sistema di pallettizzazione per migliorare e aggiornare le attività manutentive attualmente applicate

Realizzazione fisica di superfici non orientabili mediante prototipazione rapida

Il termine Prototipazione Rapida (RP da Rapid Prototyping, conosciuta anche come Solid Freeform Fabrication – SFF) si riferisce ad un insieme di tecnologie usate per costruire prototipi di oggetti tridimensionali a partire da modelli geometrici definiti solidi ricostruiti con programmi di progettazione assistita dal calcolatore (Computer Aided Design – CAD). Importanti applicazioni della Prototipazione Rapida si sono ampiamente diffuse negli ultimi anni in vari ambiti: si va dal campo industriale a quello biomedico a quello del design. La complessità geometrica delle forme solide da realizzare è conseguentemente aumentata e richiede lo studio sempre più accurato anche da un punto di vista matematico. Questo documento analizza le competenze matematiche necessarie per trattare la ricostruzione di oggetti dalla geometria particolare, come ad esempio le Superfici non orientabili (Nastro di Möbius, Bottiglia di Klein) per arrivare alla definizione di una loro parametrizzazione utile per la costruzione di modelli solidi stampabili direttamente con tecnica RP. In particolare, sono trattati i problemi legati alla generazione degli spessori necessari alla realizzazione fisica

A selective cellulose/hemicellulose green solvents extraction from buckwheat chaff

A two-phase extraction process was adopted to obtain cellulose and hemicellulose from buckwheat chaff by using green solvents. We are proposing a combination of propylene carbonate (PC) and ionic liquids (ILs) in a 1:5 ratio. We compared the first-generation ILs 1-butyl-2,3-dimethylimidazolium chloride (BdmimCl), and 1-butyl-3-methyl imidazolium acetate (BmimAc) with respect to the tetrabutyl ammonium acetate (TBAAc). The cellulose and hemicellulose were, firstly, extracted into the PC/IL mixture and subsequently precipitated by water addition. All precipitate materials were analysed by FTIR-ATR and TGA, while the organic phase and the supernatant after water addition were analysed by using self-diffusion NMR. The PC green co-solvent was proven to be an exceptional candidate to replace dimethyl sulfoxide. The highest amount of precipitate material after water addition was obtained with PC-BmimAc, while PC-TBAAc was showing the highest cellulose/hemicellulose selectivity. Furthermore, a preferential interaction of the supernatant cellulose residue with PC or acetate was observed by self-diffusion NMR

Metagenomics and microscope revealed T. trichiura and other intestinal parasites in a cesspit of an Italian nineteenth century aristocratic palace

This study evidenced the presence of parasites in a cesspit of an aristocratic palace of nineteenth century in Sardinia (Italy) by the use of classical paleoparasitological techniques coupled with next-generation sequencing. Parasite eggs identified by microscopy included helminth genera pathogenic for humans and animals: the whipworm Trichuris sp., the roundworm Ascaris sp., the flatworm Dicrocoelium sp. and the fish tapeworm Diphyllobothrium sp. In addition, 18S rRNA metabarcoding and metagenomic sequencing analysis allowed the first description in Sardinia of aDNA of the human specific T. trichiura species and Ascaris genus. Their presence is important for understanding the health conditions, hygiene habits, agricultural practices and the diet of the local inhabitants in the period under study

Glutamine Starvation Affects Cell Cycle, Oxidative Homeostasis and Metabolism in Colorectal Cancer Cells

Cancer cells adjust their metabolism to meet energy demands. In particular, glutamine addiction represents a distinctive feature of several types of tumors, including colorectal cancer. In this study, four colorectal cancer cell lines (Caco-2, HCT116, HT29 and SW480) were cultured with or without glutamine. The growth and proliferation rate, colony-forming capacity, apoptosis, cell cycle, redox homeostasis and metabolomic analysis were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT), flow cytometry, high-performance liquid chromatography and gas chromatography/mass spectrometry techniques. The results show that glutamine represents an important metabolite for cell growth and that its deprivation reduces the proliferation of colorectal cancer cells. Glutamine depletion induces cell death and cell cycle arrest in the GO/G1 phase by modulating energy metabolism, the amino acid content and antioxidant defenses. Moreover, the combined glutamine starvation with the glycolysis inhibitor 2-deoxy-D-glucose exerted a stronger cytotoxic effect. This study offers a strong rationale for targeting glutamine metabolism alone or in combination with glucose metabolism to achieve a therapeutic benefit in the treatment of colon cancer

Clinical Features and Outcome of 79 Dogs With Digital Squamous Cell Carcinoma Undergoing Treatment: A SIONCOV Observational Study

In dogs, digit squamous cell carcinoma (SCC) is uncommon. Clinical signs are frequently underestimated, leading to a diagnostic delay. The purpose of this retrospective study was to report our experience regarding the clinical presentation, diagnostic work-up, treatment and outcome of 79 client-owned dogs with SCC of the digit. The greatest majority (84.8%) of dogs was dark-coated. Schnauzers represented approximately one third of the study population, and had a poorer outcome compared with other breeds. The majority of SCCs occurred in the front limbs (61%), and bone lysis was frequently observed (92.4%). Approximately 9% of dogs had involvement of multiple digits, and this was associated with a shorter time to progression (TTP; P = 0.047). Similarly, a duration of clinical signs >90 days was associated with a shorter TTP (P = 0.02). Regional lymph node metastases were documented in 17.7% of dogs at admission and were significantly associated with tumor-related death (P < 0.001). At presentation, none of the dogs had evidence of distant metastasis. Digit amputation achieved adequate local tumor control in the majority of cases. Adjuvant chemotherapy and radiation therapy were carried out in 21.5% of cases, with uncertain benefit. Due to the relatively non-aggressive clinical behavior of digit SCC, chemotherapy should only be offered in the case of metastatic disease. Approximately one fourth of dogs developed de novo SCCs during the follow-up. Careful examination of the digits should be encouraged in breeds considered at high risk and in dogs with a previous history of digital SCC

Vitamin C Cytotoxicity and Its Effects in Redox Homeostasis and Energetic Metabolism in Papillary Thyroid Carcinoma Cell Lines.

High-dose of vitamin C (L-ascorbic acid, ascorbate) exhibits anti-tumoral effects, primarily mediated by pro-oxidant mechanisms. This cytotoxic effect is thought to affect the reciprocal crosstalk between redox balance and cell metabolism in different cancer types. Vitamin C also inhibits the growth of papillary thyroid carcinoma (PTC) cells, although the metabolic and redox effects remain to be fully understood. To shed light on these aspects, PTC-derived cell lines harboring the most common genetic alterations characterizing this tumor were used. Cell viability, apoptosis, and the metabolome were explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT), flow cytometry, and UHPLC/MS. Changes were observed in redox homeostasis, with increased reactive oxygen species (ROS) level and perturbation in antioxidants and electron carriers, leading to cell death by both apoptosis and necrosis. The oxidative stress contributed to the metabolic alterations in both glycolysis and TCA cycle. Our results confirm the pro-oxidant effect of vitamin C as relevant in triggering the cytotoxicity in PTC cells and suggest that inhibition of glycolysis and alteration of TCA cycle via NAD+ depletion can play an important role in this mechanism of PTC cancer cell death