Annealing of bismuth telluride-based thick films by laser irradiation

Interest towards fabrication and post-processing of thermoelectric micro-sized devices has increased in recent years. The coupling of inexpensive deposition technologies and fast laser treatments on “as-deposited” films is an attractive solution for industrial scalability. In this work, we propose an approach never reported before in literature: the utilization of a ns-pulsed active fibre laser to directly densify p-type bismuth telluride-based thick films deposited on silicon. A feasibility study was conducted on the material to determine optimal laser parameters: the treated products were characterized, and it was concluded that a value of laser fluence as low as 4.5 mJ cm−2 is sufficient for densification. The material resulted cracked after the laser treatment, and it was demonstrated by SEM and profilometric analyses that shrinking occurs and sintering necks are formed; further, the arising of second phases after annealing was excluded by means of XRD analysis. Envisioning an industrial large area process with linear diode arrays source, a prediction of the laser power requirements to irradiate 1 mm2 films in selected conditions is presented. More extensive studies will be performed to determine a narrower parameters window and determine a relationship between the film thickness and laser parameters for future applications to as-deposited films

Mesalamine-induced myopericarditis in children: a case report and a short revision of the literature

Mesalamine has a central role in the treatment of inflammatory bowel disease (IBD). Myocarditis and/or pericarditis are rare and severe side effects of mesalamine-containing drugs. We describe the case of a 14 years old boy, developing myopericarditis two weeks after starting mesalamine treatment for ulcerative colitis (UC). The adverse effect had a massive impact on the left ventricular function and required immedi-ate intervention. Once identified as possible causative agent, mesalamine was discontinued with subsequent improvement of the clinical symptoms and laboratory findings. No recurrency nor sequelae were detected at the cardiological follow up. Mesalamine is a widely used drug for pediatric IBD treatment, although its effect on heart tissues is a rare but potentially fatal adverse reaction. At the time of presentation, in April 2021, 10 pediatric cases were reported in literature (2 children and 8 adolescents). Of them, 60% were treated with me-salamine for UC and 40% for Chron’s disease (CD). Chest pain and fever were the most common symptoms at presentation (100% and 50% respectively), cough and fatigue were less represented. None of the patients developed sequelae at follow up. In patients treated with mesalamine early recognition of side effects, drug discontinuation and accurate therapy are crucial to prevent progression of the inflammation and to avoid adverse cardiovascular outcomes. (www.actabiomedica.it)

Caratterizzazione ad usura di rivestimenti PVD con e senza laser texturing

Il processo di laser texturing (LST) è una delle tecniche più promettenti nel campo delle microlavorazioni superficialiin quanto consente di ottenere un eccellente controllo della forma e delle dimensioni delle microcavitàprodotte ed è estremamente veloce e senza ricadute dannose per l’ambiente. Recentemente si è assistito allosviluppo di diversi lavori nei quali il laser è stato impiegato per migliorare il comportamento tribologico di componentimeccanici in materiale metallico. Le microcavità, realizzate per ablazione dal fascio laser sulla superficiedi interesse, infatti hanno diversi aspetti positivi da questo punto di vista perché generano un sistema diffusodi microspinte idrodinamiche sulla superficie e agiscono come riserve di lubrificante da una parte e come trappoleper i detriti di usura dall’altra, ritardando così, l’innesco di meccanismi di usura da terzo corpo. Nel presentelavoro si presentano i risultati di una sperimentazione volta a valutare l’effetto dell’introduzione di unalavorazione superficiale di texturing laser sulla superficie di riporti PVD in TiN. Per il texturing è stata utilizzatauna sorgente laser in fibra innovativa ad alta efficienza che ha consentito, una volta ottimizzati i parametridi processo, di ottenere dimensioni controllate delle microcavità, una buona geometria delle stesse e di evitarela presenza di residui di lavorazione anche sui coating ceramici oggetto dello studio. I test di usura in condizionidi strisciamento lubrificato con alto carico applicato e bassa velocità relativa , sono stati condotti sul rivestimentoTiN microlavorato e per confronto sul tal quale e su un rivestimento autolubrificante commerciale,il WC/C. I risultati ottenuti mostrano un marcato incremento delle prestazioni a usura per il rivestimento lasercon texturing (fino al 50% di riduzione del volume di usura) e l’assenza di significativi danneggiamenti del rivestimentoin presenza delle microcavità e delle sollecitazioni di usura applicate. Nel breve futuro si eseguiràpertanto un approfondimento ulteriore per valutare anche l’economia di scala del ciclo di lavorazione

Corrosion behavior and surface properties of PVD coatings for mold technology applications

Chrome plating is still one of the best solutions to coat martensitic steel used in the molding of plastics and rubbers. However, current stringent regulations on environmental impact call for more sustainable processes. In the present work, some physical vapor deposition (PVD) nitride coatings were produced on X155CrMoV12 steel and characterized in terms of both corrosion behavior and surface properties. Results indicated that titanium-based PVD coatings could be a valuable alternative to chromium-based coatings as they exhibited a good compromise between corrosion and surface properties. AlTiN and TiN PVD coatings exhibited adequate hardness for plastic mold applications, with AlTiN reaching hardness as high as 2000 HV. Moreover, the critical loads and adhesion properties were found to be definitely better than those of chromium-based coatings. From a corrosion point of view, the presence of multilayers in AlTiN did not seem to be beneficial as the breakdown potential for TiN (single layer) was ca. 1.1 V vs. saturated calomel electrode (SCE) compared to 0.85 V vs. SCE for AlTiN in aggressive media (NaCl)

Extracellular volume measured by whole body CT scans predicts chronic cardiotoxicity in breast cancer patients treated with neoadjuvant therapies based on anthracyclines: A retrospective study

introduction: neoadjuvant chemotherapies for breast cancer (BC) are effective but potentially cardiotoxic, and expose long survivors at risk of chemotherapy-related cardiac dysfunction (CTRCD). Unfortunately, early screening for CTRCD has actual diagnostic limits. myocardial extracellular volume (mECV) is a radiological marker used in cardiac CT scans and cardiac magnetic resonance for diagnosis and follow-up of CTRCD. It can be measured in whole-body CT (WB-CT) scan, routinely performed in patients at high risk of relapse, to evaluate CTRCD occurrence during oncological follow-up. methods: 82 WB-CT scans were examined at baseline (T0) and during oncological follow-up at first year (T1) and fifth year (T5) after the end of neoadjuvant treatment. mECV was measured at 1 min (PP) and 5 min (DP) after contrast injection. 31 echocardiograms were retrieved in T1 to perform a linear correlation between mECV and left ventricular ejection fraction (LVEF). results: mECV values in T0 were similar between the two groups both in PP and in DP. Significant results were found for PP values in T1 (37.0 % vs 32 %, p = 0.0005) and in T5 (27.2 % vs 31.2 %, p = 0.025). a cut-off value of 35 % in PP proved significant in T1 (OR = 12.4, p = 0.004), while mECV was inversely correlated with LVEF both in PP (adj-S = -3.54, adj-p = 0.002) and in DP (adj-S = -2.51, adj-p = 0.0002), suggesting a synergistic action with the age at diagnosis (p < 0.0001, respectively). conclusions: WB-CT scans performed during oncological reassessment in patients at high-risk of recurrence could be used for CTRCD screening in cardiovascular low-risk patients, especially in aging patients with mECV values above 35 %

DNA damage and transcriptional regulation in iPSC-derived neurons from Ataxia Telangiectasia patients

Abstract Ataxia Telangiectasia (A-T) is neurodegenerative syndrome caused by inherited mutations inactivating the ATM kinase, a master regulator of the DNA damage response (DDR). What makes neurons vulnerable to ATM loss remains unclear. In this study we assessed on human iPSC-derived neurons whether the abnormal accumulation of DNA-Topoisomerase 1 adducts (Top1ccs) found in A-T impairs transcription elongation, thus favoring neurodegeneration. Furthermore, whether neuronal activity-induced immediate early genes (IEGs), a process involving the formation of DNA breaks, is affected by ATM deficiency. We found that Top1cc trapping by CPT induces an ATM-dependent DDR as well as an ATM-independent induction of IEGs and repression especially of long genes. As revealed by nascent RNA sequencing, transcriptional elongation and recovery were found to proceed with the same rate, irrespective of gene length and ATM status. Neuronal activity induced by glutamate receptors stimulation, or membrane depolarization with KCl, triggered a DDR and expression of IEGs, the latter independent of ATM. In unperturbed A-T neurons a set of genes (FN1, DCN, RASGRF1, FZD1, EOMES, SHH, NR2E1) implicated in the development, maintenance and physiology of central nervous system was specifically downregulated, underscoring their potential involvement in the neurodegenerative process in A-T patients

Clinical presentation of celiac disease and diagnosis accuracy in a single-center european pediatric cohort over 10 years

(1) Background: Changes in the clinical presentation of celiac disease (CD) in children have been reported. The guidelines of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) allow esophagogastroduodenoscopy (EGD) with biopsies to be avoided under specific circumstances. We aimed to assess the clinical picture of pediatric CD patients at diagnosis and to validate ESPGHAN non-biopsy criteria. (2) Methods: Patients with suspected CD or undergoing screening from 2004 to 2014 at the University Hospital in Modena, Italy were enrolled. The accuracy of ESPGHAN non-biopsy criteria and modified versions were assessed. (3) Results: In total, 410 patients were enrolled, of whom 403 were considered for analysis. Of the patients considered, 45 were asymptomatic and diagnosed with CD (11.2%) while 358 patients (88.2%) were symptomatic, of whom 295 were diagnosed with CD. Among symptomatic CD patients, 57 (19.3%) had gastrointestinal symptoms, 98 (33%) had atypical symptoms and 140 (47.4%) had both. No difference was found for the presence of gastrointestinal symptoms at different ages. The non-biopsy ESPGHAN criteria yielded an accuracy of 59.4% with a positive predictive value (PPV) of 100%; 173 out of 308 EGD (56.2%) could have been avoided. The modified 7× and 5× upper limit of normal cut-offs for IgA anti tissue-transglutaminase reached 60.7% and 64.3% of EGD avoided, respectively. (4) Conclusions: Over 10 years, late age at diagnosis and increased rates of atypical CD presentation were found. ESPGHAN non-biopsy criteria are accurate for CD diagnosis and allow half of unneeded EGD to be avoided. Modified versions allowed sparing a greater number of EGD

SPARC regulation of PMN clearance protects from pristane-induced lupus and rheumatoid arthritis

The secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein with unexpected immunosuppressive function in myeloid cells. We investigated the role of SPARC in autoimmunity using the pristane-induced model of lupus that, in mice, mimics human systemic lupus erythematosus (SLE). Sparc−/− mice developed earlier and more severe renal disease, multi-organ parenchymal damage, and arthritis than the wild-type counterpart. Sparc+/- heterozygous mice showed an intermediate phenotype suggesting Sparc gene dosage in autoimmune-related events. Mechanistically, reduced Sparc expression in neutrophils blocks their clearance by macrophages, through defective delivery of don't-eat-me signals. Dying Sparc−/− neutrophils that escape macrophage scavenging become source of autoantigens for dendritic cell presentation and are a direct stimulation for γδT cells. Gene profile analysis of knee synovial biopsies from SLE-associated arthritis showed an inverse correlation between SPARC and key autoimmune genes. These results point to SPARC down-regulation as a leading event characterizing SLE and rheumatoid arthritis pathogenesis

Trattamento di nitrurazione ionica di una lega di titanio commercialmente puro e di una lega Ti-6Al-4V

Nel presente lavoro sono state analizzate due leghe di titanio sottoposte a trattamenti di nitrurazione ionicaal fine di indagare l’influenza sia della composizione del materiale trattato sia dei parametri di processoutilizzati. Le indagini sperimentali sono state svolte attraverso analisi della microstruttura, misuredi composizione nello spessore mediante spettroscopia a emissione ottica e profili di microdurezza.Tra i risultati ottenuti si è evidenziato come i maggiori valori nei profili di microdurezza e di composizionenello spessore nitrurato si riscontrino nei campioni sottoposti a trattamenti prolungati o a cicli di diffusionealternati ai periodi di esposizione in atmosfera attiva. Si è dimostrato come l’arricchimento di azoto avvengain misura maggiore nella lega di Ti-6Al-4V rispetto al titanio commercialmente puro a parità di condizionidi trattamento. Infine nella lega Ti-6Al-4V durante il trattamento di nitrurazione si è misurato un accumulodi alluminio e di vanadio immediatamente a valle dello strato dei composti che contribuisce ad incrementarela durezza degli strati sub- superficiali

Synthesis and biological evaluation of dual action cyclo-RGD/SMAC mimetic conjugates targeting αvβ3/αvβ5 integrins and IAP proteins

The rational design, synthesis and in vitro biological evaluation of dual action conjugates 11-13, containing a tumour targeting, integrin a(v)beta(3)/a(v)beta(5) ligand portion and a pro-apoptotic SMAC mimetic portion (cyclo-RGD/SMAC mimetic conjugates) are reported. The binding strength of the two separate units is generally maintained by these dual action conjugates. In particular, the connection between the separate units (anchor points on each unit; nature, length and stability of the linker) influences the activity of each portion against its molecular targets (integrins a(v)beta(3)/a(v)beta(5) for cyclo-RGD, IAP proteins for SMAC mimetics). Each conjugate portion tolerates different substitutions while preserving the binding affinity for each target