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•ZnO-CuO dispersion on activated carbon enhances H2S adsorption capacity.•Effect of Cu:Zn ratio investigated at fixed total metal loading in the sorbent.•H2S dynamic adsorption tests ...run at 30°C in N2 followed by TPD of H2S and SO2.•Cu addition improves adsorption capacity and active phase utilization factor.•Reactive H2S adsorption forms both metal sulphates and sulphides.
Sorbents for low temperature reactive adsorption of H2S were prepared by dispersing mixed Zn and Cu oxides onto a commercial activated carbon at fixed total metal loading and Cu:Zn atomic ratios from 0:1 to 1:1. Fresh and spent sorbents were characterized by means of ICP-MS, SEM-EDX, XRD, BET and pore size distribution, DRIFT and sulphur elemental analysis. H2S (50–3000ppmv in N2) removal tests were run under dynamic conditions at 30°C. Due to the high dispersion of the metal oxide phase and its favorable interaction with the carbonaceous support, the functionalized sorbents showed a strongly enhanced adsorption capacity with respect to the raw activated carbon, under dry conditions. Furthermore, the utilization factor of the active phase (moles of S captured per mole of Cu+Zn) increased along with the Cu content up to 76%, thus demonstrating a clear promoting effect of Cu-insertion on the reactivity of ZnO, already at low Cu concentration. Temperature Programmed Desorption (TPD) of H2S and SO2 from saturated sorbents showed that H2S adsorption was coupled with oxidation phenomena leading to the formation of metal sulphates apart from metal sulphides and/or elemental sulphur, testifying the complexity of the surface reactions.
In this paper we experimentally demonstrate that SiC high voltage Power MOSFTEs exhibit an unstable electro-thermal behavior for given electrical conditions, depending on the chip thermal impedance. ...This instability can lead to hot-spot formation and eventually thermal runaway whit subsequent device destruction after a stressful short-circuit. The analysis was carried out on a commercial 1.2kV SiC Power MOSFET by investigating the device electro-thermal behavior in short-circuit operation with a state-of-art IR thermographic set-up. By biasing the device at different gate voltages, the stable and unstable regions are evidenced with electrical and thermal measurements. Finally an unstable behavior is triggered and an hot-spot coherent with the failure location is demonstrated.
Reactive adsorption of hydrogen sulphide (H2S) from gaseous streams at room temperature with mixed Zn and Cu active phase supported onto γ-alumina is dealt in this manuscript. Sorbents with a fixed ...total metal content and variable Cu:Zn ratios were prepared by impregnation of commercial γ-alumina spheres in order to investigate the role of the support and the possible synergic effect between the two metals on the adsorption mechanism and performance. H2S (500–3000 ppmv in N2) removal tests were run under dynamic conditions at 30 °C. Experimental techniques such as BET and pore size distribution by N2-adsorption, SEM-EDX, XRD and DRIFT analysis were coupled for the characterization of fresh and spent sorbents. TPD/TPO experiments on saturated sorbents were performed to assess their regenerability and allowed the speciation of adsorbed sulphur species, testifying the complexity of the surface reactions and the effect of the support.
Sporadic Burkitt lymphoma (sBL) can be delineated from diffuse large B-cell lymphoma (DLBCL) by a very homogeneous mRNA expression signature. However, it remained unclear whether all three BL ...variants-sBL, endemic BL (eBL) and human immunodeficiency virus-associated BL (HIV-BL)-represent a uniform biological entity despite their differences in geographical occurrence, association with immunodeficiency and/or incidence of Epstein-Barr virus (EBV) infection. To address this issue, we generated micro RNA (miRNA) profiles from 18 eBL, 31 sBL and 15 HIV-BL cases. In addition, we analyzed the miRNA expression of 86 DLBCL to determine whether miRNA profiles recapitulate the molecular differences between BL and DLBCL evidenced by mRNA profiling. A signature of 38 miRNAs containing MYC regulated and nuclear factor-kB pathway-associated miRNAs was obtained that differentiated BL from DLBCL. The miRNA profiles of sBL and eBL displayed only six differentially expressed miRNAs, whereas HIV and EBV infection had no impact on the miRNA profile of BL. In conclusion, miRNA profiling confirms that BL and DLBCL represent distinct lymphoma categories and demonstrates that the three BL variants are representatives of the same biological entity with only marginal miRNA expression differences between eBL and sBL.
Abstract Worldwide, gastric cancer represents the fifth most common cancer and the third leading cause of cancer deaths. Although the overall 5-year survival for resectable disease was more than 70% ...in Japan due to the implementation of screening programs resulting in detection of disease at earlier stages, in Western countries more than two thirds of gastric cancers are usually diagnosed in advanced stages reporting a 5-year survival rate of only 25.7%. Anyway surgical resection with extended lymph node dissection remains the only curative therapy for non-metastatic advanced gastric cancer, while neoadjuvant and adjuvant chemotherapies can improve the outcomes aimed at the reduction of recurrence and extension of survival. High-quality research and advances in technologies have contributed to well define the oncological outcomes and have stimulated many clinical studies testing multimodality managements in the advanced disease setting. This review article aims to outline and discuss open issues in current surgical management of advanced gastric cancer.
Solid epidemiological evidences connect obesity with incidence, stage and survival in pancreatic cancer. However, the underlying mechanistic basis linking adipocytes to pancreatic cancer progression ...remain largely elusive. We hypothesized that factors secreted by adipocytes could be responsible for epithelial-to-mesenchymal transition (EMT) induction and, in turn, a more aggressive phenotype in models of pancreatic preneoplastic lesions.
We studied the role of factors secreted by two adipogenic model systems from primary human bone marrow stromal cells (hBMSCs) in an in vitro experimental cell transformation model system of human pancreatic ductal epithelial (HPDE) cell stably expressing activated KRAS (HPDE/KRAS),Results:We measured a significant induction of EMT and aggressiveness in HPDE and HPDE/KRAS cell lines when cultured with medium conditioned by fully differentiated adipocytes (ADIPO
) if compared with the same cells cultured with medium conditioned by hBMSC (hBMSC
) from two different healthy donors. Several genes coding for soluble modulators of the non-canonical WNT signaling pathway, including FRZB, SFRP2, RSPO1, WNT5A and 5B were significantly overexpressed in fully differentiated adipocytes than in their respective in hBMSC. ADIPO
induced the overexpression and the nuclear translocation of the Frizzled family member receptor tyrosine kinase-like orphan receptor (Ror) 2 in HPDE and HPDE/KRAS cells. Vantictumab, an anti-Frizzled monoclonal antibody, reduced ROR2 nuclear translocation and in turn the EMT and aggressiveness in HPDE and HPDE/KRAS cells.
We demonstrated that adipocytes could induce EMT and aggressiveness in models of pancreatic preneoplastic lesions by orchestrating a complex paracrine signaling of soluble modulators of the non-canonical WNT signaling pathway that determine, in turn, the activation and nuclear translocation of ROR2. This signaling pathway could represent a novel target for pancreatic cancer chemoprevention. Most importantly, these factors could serve as novel biomarkers to select a risk population among obese subjects for screening and, thus, early diagnosis of pancreatic cancer.
The protein product of the retinoblastoma (RB) gene is necessary for the completion of the muscle differentiation program and for myogenic basic helix-loop-helix-dependent transcription. In fact, in ...addition to induction and maintenance of permanent cell cycle withdrawal through negative regulation of E2F-responsive genes involved in proliferation, pRb also plays a positive role in the activation of muscle-specific genes. In pRb-/- myocytes, the expression of late myogenic markers is defective and myoblast fusion into myotubes occurs without irreversible cell cycle exit. This evidence demonstrates only a partial functional redundancy between pRb and its relatives p107 and pRb2/p130, as these pRb-/- multinucleated cells, which display p107 levels higher than normal myotubes, respond to mitogens with cell cycle re-entry and DNA synthesis. At the molecular level, pRb myogenic functions are mediated by cooperation with MyoD, Myocyte enhancer factor 2 (MEF2), High mobility group box protein-1 (HBP1) and histone deacetylase1, affecting chromatin configuration and tissue-specific transcription, and by post-translational modification in response to intracellular signaling cascades.
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