One of the most important purposes of the modern industry is a sustainable production, considering the minimization of the energy and of the raw materials used, together with the reduction of polluting emissions. In this context, Friction Stir Extrusion stands out, since it allows to obtain extrusions starting from metal scraps deriving from traditional mechanical machining processes (e.g.
View Article and Find Full Text PDFInt J Med Inform
February 2023
The global spread of COVID-19 and the declaration of the pandemic status made by the World Health Organization (WHO) led to the establishment of mass vaccination campaigns. The challenges posed by the request to immunise the entire population necessitated the set-up of new vaccination sites, named Mass Vaccination Centres (MVCs), capable of handling large numbers of patients rapidly and safely. The present study focused on the evolution of MVC performances, in terms of the maximum number of vaccinated patients and primary resource utilisation ratio, while involving statistics belonging to the patient dimension.
View Article and Find Full Text PDFWe believe that the chosen topic is nowadays extremely current and of great interest [...
View Article and Find Full Text PDFArtificial Neural Network (ANN), together with a Particle Swarm Optimization (PSO) and Finite Element Model (FEM), was used to forecast the process performances for the Micro Electrical Discharge Machining (micro-EDM) drilling process. The integrated ANN-PSO methodology has a double direction functionality, responding to different industrial needs. It allows to optimize the process parameters as a function of the required performances and, at the same time, it allows to forecast the process performances fixing the process parameters.
View Article and Find Full Text PDFThe paper is devoted to the study of stress corrosion cracking phenomena in friction stir welding AA-2024 T3 joints. Constant load (CL) cell and slow strain rate (SSR) tests were carried out in aerated NaCl 35 g/L solution. During the tests, open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) were measured in the different zones of the welding.
View Article and Find Full Text PDFThe paper focuses on the corrosion behavior of aluminum joints made by friction stir welding as a function of loading conditions. A four-points bend-beam test, constant loading test, and slow strain-rate test were carried out on AA 7075-T6 alloy in aerated NaCl 35g/L solution at room temperature monitoring the free corrosion potential. The penetration depth of the intergranular attack was deeper after the four-point bent-beam tests compared to all the other testing techniques.
View Article and Find Full Text PDFThe present work deals with the execution of through micro-holes on tungsten carbide plates using a micro-electrical discharge machining (micro-EDM) machine. The experiments were carried out by varying peak current, voltage and frequency in order to achieve suitable technology windows. Tubular electrodes, made of two different materials (tungsten carbide and brass), were used.
View Article and Find Full Text PDFThe present study was carried out to evaluate how the friction stir spot welding (FSSW) process parameters affect the temperature distribution in the welding region, the welding forces and the mechanical properties of the joints. The experimental study was performed by means of a CNC machine tool obtaining FSSW lap joints on AA7050 aluminum alloy plates. Three thermocouples were inserted into the samples to measure the temperatures at different distance from the joint axis during the whole FSSW process.
View Article and Find Full Text PDFDetermination of liver iron concentration is essential to predict iron related tissue damage and to guide chelation therapy. To assess the reliability of a single biopsy iron concentration determination in representing the whole liver iron concentration, we conducted a prospective study performing two immediately successive liver biopsies from 61 noncirrhotic, iron overloaded thalassemia patients, directing the needle to different direction from the same skin cut. The correlation among sample biopsies was determined by both regression analysis and the Bland-Altman method.
View Article and Find Full Text PDFHaematologica
May 2014
Thalassemia major and sickle cell disease are the two most widely disseminated hereditary hemoglobinopathies in the world. The outlook for affected individuals has improved in recent years due to advances in medical management in the prevention and treatment of complications. However, hematopoietic stem cell transplantation is still the only available curative option.
View Article and Find Full Text PDFMaterials (Basel)
September 2013
In the most recent decades the introduction of unconventional machining processes allowed the development of micromachining techniques. In this work, the influence of material microstructures on the micromilling process was investigated. Ti6Al4V alloy was selected as workpiece material since it is a very common material for micro applications and because its duplex microstructure can be easily changed by proper thermal treatments.
View Article and Find Full Text PDFA 9-year-old female received an allogeneic stem cell transplant (SCT) from an ABO-incompatible HLA-matched sibling for β-thalassemia major, without achieving a complete donor chimerism. Subsequently, the patient received five donor lymphocyte infusions, without increasing donor chimerism, and autologous SCT. Due to the persistent bone marrow aplasia, the patient received a second allogeneic SCT from the same donor without obtaining any engrafment.
View Article and Find Full Text PDFMiniaturization encourages the development of new manufacturing processes capable of fabricating features, like micro-channels, in order to use them for different applications, such as in fuel cells, heat exchangers, microfluidic devices and micro-electromechanical systems (MEMS). Many studies have been conducted on heat and fluid transfer in micro-channels, and they appeared significantly deviated from conventional theory, due to measurement errors and fabrication methods. The present research, in order to deal with this opportunity, is focused on a set of experiments in the micro-milling of channels made of aluminum, titanium alloys and stainless steel, varying parameters, such as spindle speed, depth of cut per pass (), channel depth (), feed per tooth () and coolant application.
View Article and Find Full Text PDFPolymorphisms of the cytotoxic T-lymphocyte antigen-4 gene (CTLA-4) have been associated with autoimmune diseases and it has recently been reported that donor genotypes correlate with the outcome of allogeneic hematopoietic stem cell transplantation in leukemia patients. With the aim of confirming this finding in thalassemia patients, we investigated the influence of genotype distribution of 3 CTLA-4 gene polymorphisms in 72 thalassemia patients and their unrelated donors. A significant association was observed for recipient CT60-AA genotype and onset of grade II-IV (63.
View Article and Find Full Text PDFIn a study conducted on 114 patients undergoing unrelated donor haematopoietic stem cell transplantation (HSCT) for thalassaemia, we observed that the lack of activating killer immunoglobulin-like receptors (KIRs) on donor natural killer (NK) cells significantly increased the risk of graft-versus-host disease (GvHD) [hazard risk (HR) 4.2, 95% confidence interval (CI) 1.7-10.
View Article and Find Full Text PDFWe designed a phase 1-2 study to evaluate the safety and the efficacy of increasing doses of bendamustine (160 mg/m², 180 mg/m², and 200 mg/m² given on days -7 and -6) coupled with fixed doses of etoposide, cytarabine, and melphalan (BeEAM regimen) as the conditioning regimen to autologous stem cell transplantation for resistant/relapsed lymphoma patients. Forty-three patients (median age, 47 years) with non-Hodgkin (n = 28) or Hodgkin (n = 15) lymphoma were consecutively treated. Nine patients entered the phase 1 study; no patients experienced a dose-limiting toxicity.
View Article and Find Full Text PDFSeveral studies have investigated the role played by killer immunoglobulin-like receptors (KIRs) and their ligands on the outcome of hematopoietic stem cell transplantation (HSCT) in patients affected by oncohematologic diseases. However, the interpretation of the results of these studies is considerably hampered by the heterogeneity of the diseases, disease status at transplantation, and the different protocols employed for both conditioning and graft-versus-host disease (GVHD) prophylaxis. To better define the role of KIRs in HSCT, we studied KIR genotypes and HLA class I ligands in a homogeneous group of 45 thalassemia patients transplanted with bone marrow cells from an HLA-identical, unrelated donor.
View Article and Find Full Text PDFBone marrow transplantation (BMT) remains the only potentially curative treatment for patients with thalassemia major. However, most candidates for BMT do not have a suitable family donor. In order to evaluate whether BMT from an HLA-matched unrelated volunteer donor can offer a probability of cure comparable to that obtained when the donor is a compatible sibling, we carried out a study involving 68 thalassemia patients transplanted in six Italian BMT Centers.
View Article and Find Full Text PDFThe success of allogeneic hematopoietic stem cell transplantation (HSCT) from matched unrelated donors (UDs) for beta-thalassemia may be hampered by the occurrence of graft rejection. Here, we show that the rate of this complication can be reduced by selecting 5-loci HLA-matched donors without nonpermissive mismatches at HLA-DPB1, defined according to an algorithm previously described and based on principles of central T-cell tolerance. Seventy-two consecutive patients and their UDs, prospectively selected for matching at the allelic level for HLA-A, -B, -C, -DRB, and -DQB1 loci, were enrolled in the analysis.
View Article and Find Full Text PDFWhen prepared for transplantation with busulfan (BU) 14 mg/kg and cyclophosphamide (CY) 120 to 160 mg/kg, patients with thalassemia in risk class 3, aged younger than 17 years, who receive transplants from HLA-identical donors, had a 30% incidence of transplant rejection with recurrence of thalassemia. This, relatively poor, outcome was ascribed to insufficient immune suppression or to inadequate eradication of the thalassemic marrow, or both. In an attempt to enhance both immune suppression and eradication of the thalassemic clones, hydroxyurea, azathioprine, and fludarabine were added to the BU and CY.
View Article and Find Full Text PDFAllogeneic bone marrow transplantation (BMT) from a genotypically identical family donor is an accepted therapeutic option for homozygous beta-thalassemia. However, only a minority of patients have access to this curative procedure. The aim of this study is to explore the feasibility of matched unrelated transplants in thalassemia and the possibility of reducing the risk of immunologic complications through careful selection of donor/recipient pairs.
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