228 research outputs found
Plasma defect-engineering of bulk oxygen-deficient zirconia
Oxygen-deficient zirconia (ZrO2-x) has recently emerged as a promising material for light absorption and photocatalytic applications. However, the economic and environmentally friendly manufacture of bulk ZrO2-x remains challenging and has limited widespread adoption. In this study, we present a novel low-pressure (300 Pa) plasma treatment (H2 gas at 500 °C for 5 h) capable of producing fully-dense bulk ZrO2-x without significant structural modifications. EPR (electron paramagnetic resonance) and XPS (X-ray photoelectron spectroscopy) characterisation of the plasma treated zirconia indicate the formation of Zr3+ ions and F2+ (VO··) centres. The increase of oxygen vacancies is also supported by the greater exothermic heat flow and relative mass gain observed through TGA (thermogravimetric analysis) and DSC (differential scanning calorimetry) analyses. Diffuse reflectance spectroscopy (DRS) reveals a substantial enhancement in light absorption, with an average increase of 66.2 % and >65 % absolute absorption across the entire spectrum (200–3000 nm). XPS and DRS measurements suggest significant reduction in both direct (from 4.84 to 2.61 eV) and indirect (from 3.19 to 1.45 eV) bandgap transition. By effectively enhancing the light absorption capability, reducing bandgap transitions, and maintaining the structural integrity of zirconia, low-pressure plasma treatments offer a promising and scalable approach for the environmentally friendly production of next-generation ZrO2-x materials
Ceramide-induced BOK promotes mitochondrial fission in preeclampsia
Mitochondria are in a constant balance of fusing and dividing in response to cellular cues. Fusion creates healthy mitochondria, whereas fission results in removal of non-functional organelles. Changes in mitochondrial dynamics typify several human diseases. However, the contribution of mitochondrial dynamics to preeclampsia, a hypertensive disorder of pregnancy characterized by placental cell autophagy and death, remains unknown. Herein, we show that the mitochondrial dynamic balance in preeclamptic placentae is tilted toward fission (increased DRP1 expression/activation and decreased OPA1 expression). Increased phosphorylation of DRP1 (p-DRP1) in mitochondrial isolates from preeclamptic placentae and transmission electron microscopy corroborated augmented mitochondrial fragmentation in cytotrophoblast cells of PE placentae. Increased fission was accompanied by build-up of ceramides (CERs) in mitochondria from preeclamptic placentae relative to controls. Treatment of human choriocarcinoma JEG3 cells and primary isolated cytrophoblast cells with CER 16:0 enhanced mitochondrial fission. Loss- and gain-of-function experiments showed that Bcl-2 member BOK, whose expression is increased by CER, positively regulated p-DRP1/DRP1 and MFN2 expression, and localized mitochondrial fission events to the ER/MAM compartments. We also identified that the BH3 and transmembrane domains of BOK were vital for BOK regulation of fission. Moreover, we found that full-length PTEN-induced putative kinase 1 (PINK1) and Parkin, were elevated in mitochondria from PE placentae, implicating mitophagy as the process that degrades excess mitochondria fragments produced from CER/BOK-induced fission in preeclampsia. In summary, our study uncovered a novel CER/BOK-induced regulation of mitochondrial fission and its functional consequence for heightened trophoblast cell autophagy in preeclampsia
Mechanical properties of epoxy/multi-walled carbon nanotubes composites
In this paper, two types of multi-wall carbon nanotubes (MWCNTs) were dispersed into two different epoxy resins b high - shear mixing. Dispersion and homogenisation of nanofillers was analysed by Field Emission Scanning Electron Microscopy (FESEM). Microhardness of epoxy/MWCNTs nanocomposites, as well as of neat epoxy resins, is measure by Vickers method. The evolution of nanocomposites microhardness values were studied in function of curing time takin in account the influence of two different epoxy matrix and MWCNTs. Asymptotic values were analysed and compare with those of pure epoxy resin
A narrative review of epidemiology and prevention of lung cancer: sex/gender differences?
Background and Objective: Sex and gender-related factors can both differently influence cancer susceptibility, progression, survival, and therapeutic response. Nevertheless, these differences are not extensively studied. The aim of this narrative review is to summarize sex/gender related differences in lung cancer epidemiology, the burden of its risk factors, and the role of prevention.
Methods: Through PubMed Central and official websites of International and European Agencies and Societies, recent evidence about potential differences between males and females in lung cancer epidemiology (prevalence, temporal/spatial trend, biomarkers), risk factors (tobacco smoking and air pollution) and prevention coming from international reports and original studies have been selected. The study was limited to published original manuscripts/reviews/reports in the English language from 1990 to 2021.
Key Content and Findings: Lung cancer is the most commonly diagnosed cancer (11.4% of the total cases), and the leading cause of cancer death (18.0% of the total cancer deaths). An increasing lung cancer incidence and mortality trends, largely but not only due to the increasing smoking prevalence, were evidenced among women. Females seem to be more susceptible to carcinogenic effect of tobacco smoke, and hormonal factors, use of hormone replacement therapy (HRT) and genetic predisposition are suggested to affect susceptibility to lung cancer. The incidence of lung cancer among females is globally increasing also in those who doesn’t smoke. Therefore, it becomes important to investigate the influence of other factors such as environmental tobacco exposure (ETS), outdoor and indoor air pollution, occupational exposure to hazardous chemicals and radon exposure from soil and building materials. The risk of lung cancer can be significantly reduced with tobacco cessation. Sex/gender differences in smoking cessation rates have been hypothesized with contrasting results.
Conclusions: Lung cancer prevalence, trend and susceptibility as well as efficacy of risk factors preventive measures (e.g., smoking cessation) are a result of sex and gender differences, thus both aspects should be considered as contributing factors in lung cancer management
Convective Heat Transfer Enhancement for Electronic Device Applications using Patterned MWCNTs Structures
This article reports on the heat transfer characteristics of columnar Vertically Aligned Multiwall Carbon Nanotubes (VA-MWCNTs) grown on a patterned Si surface. In the first part, we describe the procedure for patterning the silicon (Si) surface and the growth of MWCNTS on these patterned surfaces. The diameter of MWCNTs grown by Chemical Vapor Deposition (CVD) technique was in the range of 30-80 nm. In the second part structures mimicking macroscopic finned heat sinks are used for enhancing forced convective heat transfer on a silicon substrate. Convective heat transfer coefficient has been experimentally measured for silicon substrates with and without MWCNT-based fins on it. The configuration with MWCNTs based fins shows an enhancement in convective heat transfer of 40% and 20%, as maximum and average value respectively, compared to the bare silicon. Experiments have been carried out in a wind tunnel with air as coolant in fully turbulent regime. These encouraging results and the possibility of growing structures directly on silicon can be regarded as a first step
Essential oil composition from hop cultivated at Southern Brazil.
Edition of Abstracts of the 48th International Symposium on Essential Oils, PĂ©cs, Hungary, 2017. Abstracts. Babedio, 2017. ISEO 2017, 10 a 13 set. 2017. P-05
Effect of the ingestion in the WRF model of different Sentinel-derived and GNSS-derived products: analysis of the forecasts of a high impact weather event
This paper presents the first experimental results of a study on the ingestion in the Weather Research and Forecasting (WRF) model, of Sentinel satellites and Global Navigation Satellite Systems (GNSS) derived products. The experiments concern a flash-floodevent occurred in Tuscany (Central Italy) in September 2017. The rationale is that numerical weather prediction (NWP) models are presently able to produce forecasts with a km scale spatial resolution, but the poor knowledge of the initial state of the atmosphere may imply an inaccurate simulation of the weather phenomena. Hence, to fully exploit the advances in numerical weather modelling, it is necessary to feed them with high spatiotemporal resolution information over the surface boundary and the atmospheric column. In this context, the Copernicus Sentinel satellites represent an important source of data, because they can provide a set of high-resolution observations of physical variables (e.g. soil moisture, land/sea surface temperature, wind speed) used in NWP models runs. The possible availability of a spatially dense network of GNSS stations is also exploited to assimilate water vapour content. Results show that the assimilation of Sentinel-1 derived wind field and GNSS-derivedwater vapour data produce the most positive effects on the performance of the forecast
Effets de l'ozone sur la forêt et la végétation dans les Alpes franco-italiennes.
Depuis le début des années 80, dans le sud des Alpes (frontière franco-italienne), plusieurs essences ont présenté des endommagements de leur feuillage avec un déficit foliaire bien marqué. Des premières études ont montré que la pollution par l'ozone influait sur le mauvais état de santé général des peuplements concernés. A partir de 1999, il importait d'évaluer (programme européen Interreg II) l'impact spécifique de la pollution par l'ozone sur les dommages observés. Les premiers résultats ont révélé des concentrations en ozone élevées. Parallèlement, l'endommagement foliaire a été estimé sur des placettes forestières. Ont été recherchés également des symptômes spécifiques de l'ozone sur quelques essences arborées, mais aussi sur toute la végétation de proximité. Des essais de corrélation ont été réalisés entre les niveaux d'ozone et les dégâts foliaires observés et des analyses microscopiques ont permis de confirmer la spécificité des dégâts observés
Modular plastic chip for one-shot human papillomavirus diagnostic analysis.
In this article, we report the design and development of a plastic modular chip suitable for one-shot human papillomavirus (HPV) diagnostics, namely detection of the viral presence and relative genotyping, by two sequential steps performed directly on the same device. The device is composed of two modular and disposable plastic units that can be assembled or used separately. The first module is represented by a polydimethylsiloxane (PDMS) microreactor that is exploited for real-time polymerase chain reaction (PCR) and, thus, is suitable for detecting the presence of virus. The second unit is a PDMS microwell array that allows virus genotyping by a colorimetric assay, based on DNA hybridization technology developed on plastic, requiring simple inspection by the naked eye. The two modules can be easily coupled to reusable hardware, enabling the heating/cooling processes and the real-time detection of HPV. By coupling real-time assay and colorimetric genotyping on the same chip, the assembled device may provide a low-cost tool for HPV diagnostics, thereby favoring the prediction of cancer risk in patients
Screening of a Small Number of Italian COVID-19 Syndrome Survivors by Means of the Fatigue Assessment Scale: Long COVID Prevalence and the Role of Gender
Months after healing, a number of COVID-19 syndrome survivors are affected by both psychological and physical limitations. They are mainly troubled with long-term fatigue, which is a crucial aspect of Long Covid syndrome. This paper aims to investigate the level and persistency of fatigue among COVID-19 survivors from the first wave of the pandemic in Western Liguria and to elucidate the role of gender, age, and lifestyle. It also provides data to the scientific community to help drawing a consistent picture of Long Covid syndrome. The patients were requested to fill a Fatigue Assessment Questionnaire twice: (i) a few weeks after discharge from hospital or home confinement and (ii) a few months later. Statistical analysis was carried out on the global scores and on the score for every single item of the questionnaire. The outcome of the two questionnaires were analyzed separately and compared. Females are more affected by fatigue than males. This results holds for both physical and mental fatigue. All the males’ fatigue scores were reduced at the second control, while 40% of females worsened it. Home-confined patients showed a higher fatigue score at the first check. In the initial stages of the recovery, patients are more affected by physical, rather than mental, fatigue. This is worth of further investigation as well as the reasons leading to a higher initial fatigue score for home cared patients
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