266 research outputs found
Hard macrocells for DC/DC converter in automotive embedded mechatronic systems
A novel configurable DC/DC converter architecture, to be integrated as hard macrocell in automotive embedded systems, is proposed in the paper. It aims at realizing an intelligent voltage regulator. With respect to the state of the art, the challenge is the integration into an automotive-qualified chip of several advanced features like dithering of switching frequency, nested control loops with both current and voltage feedback, asynchronous hysteretic control for low power mode, slope control of the power FET gate driver, and diagnostic block against out-of-range current or voltage or temperature conditions. Moreover, the converter macrocell can be connected to the in-vehicle digital network, exchanging with the main vehicle control unit status/diagnostic flags and commands. The proposed design can be configured to work both in step-up and step-down modes, to face a very wide operating input voltage range from 2.5 to 60 V and absolute range from â0.3 to 70 V. The main target is regulating all voltages required in the emerging hybrid/electric vehicles where, besides the conventional 12 V DC bus, also a 48 V DC bus is present. The proposed design supports also digital configurability of the output regulated voltage, through a programmable divider, and of the coefficients of the proportional-integrative controller inside the nested control loops. Fabricated in 0.35 ÎŒm CMOS technology, experimental measurements prove that the IC can operate in harsh automotive environments since it meets stringent requirements in terms of electrostatic discharge (ESD) protection, operating temperature range, out-of-range current, or voltage condition
Granular cell tumor of the trachea as a rare cause of dyspnea in a young woman
Tracheal granular cell tumors are rare neurogenic neoplasms characterized by an indolent behavior. We report the case of a young woman affected by this tumor with non-specific clinical presentation. We performed a literature search in order to identify all the cases of tracheal granular cell tumor and to summarize the current state of knowledge about this rare disease
Single or combined ablation of peripheral serotonin and p21 limit adipose tissue expansion and metabolic alterations in early adulthood in mice fed a normocaloric diet
Identifying the fundamental molecular factors that drive weight gain even in the absence of hypercaloric food intake, is crucial to enable development of novel treatments for the global pandemic of obesity. Here we investigated both adipose tissue-specific and systemic events that underlie the physiological weight gain occurring during early adulthood in mice fed a normocaloric diet. In addition, we used three different genetic models to identify molecular factors that promote physiological weight gain during normocaloric and hypercaloric diets. We demonstrated that normal physiological weight gain was accompanied by an increase in adipose tissue mass and the presence of cellular and metabolic signatures typically found during obesity, including adipocyte hypertrophy, macrophage recruitment into visceral fat and perturbed glucose metabolism. At the molecular level, this was associated with an increase in adipose tissue tryptophan hydroxylase 1 (Tph1) transcripts, the key enzyme responsible for the synthesis of peripheral serotonin. Genetic inactivation of Tph1 was sufficient to limit adipose tissue expansion and associated metabolic alterations. Mechanistically, we discovered that Tph1 inactivation resulted in down-regulation of cyclin-dependent kinase inhibitor p21Waf1/Cip1 expression. Single or double ablation of Tph1 and p21 were equally effective in preventing adipocyte expansion and systemic perturbation of glucose metabolism, upon both normocaloric and hypercaloric diets. Our results suggest that serotonin and p21 act as a central molecular determinant of weight gain and associated metabolic alterations, and highlights the potential of targeting these molecules as a pharmacologic approach to prevent the development of obesity
Polarization Control in Integrated Graphene-Silicon Quantum Photonics Waveguides
We numerically investigated the use of graphene nanoribbons placed on top of silicon-on-insulator (SOI) strip waveguides for light polarization control in silicon photonic-integrated waveguides. We found that two factors mainly affected the polarization control: the graphene chemical potential and the geometrical parameters of the waveguide, such as the waveguide and nanoribbon widths and distance. We show that the graphene chemical potential influences both TE and TM polarizations almost in the same way, while the waveguide width tapering enables both TE-pass and TM-pass polarizing functionalities. Overall, by increasing the oxide spacer thickness between the silicon waveguide and the top graphene layer, the device insertion losses can be reduced, while preserving a high polarization extinction ratio
Traceability and authentication in agri-food production: A multivariate approach to the characterization of the Italian food excellence elephant garlic (Allium ampeloprasum L.), a vasoactive nutraceutical
A research platform for food authentication was set up by combining stable isotope ratio analysis, metabolomics by gas and liquid mass-spectrometry and NMR investigations, chemometric analyses for food excellences. This multi-analytical approach was tested on samples of elephant garlic (Allium ampeloprasum L.), a species belonging to the same genus of common garlic (Allium ampeloprasum L.), mainly produced in southern Tuscany-(Allium ampeloprasum). The isotopic composition allowed the product to be geographically characterized. Flavonoids, like (+)-catechin, cinnamic acids, quercetin glycosides were identified. The samples showed also a significant amount of dipeptides, sulphur-containing metabolites and glutathione, the latter of which could be considered a molecular marker of the analyzed elephant garlic. For nutraceutical profiling to reach quality labels, extracts were investigated in specific biological assays, displaying interesting vasorelaxant properties in rat aorta by mediating nitric oxide release from the endothelium and exhibited positive inotropic and negative chronotropic effects in rat perfused heart
Superomedial pedicle skin-reducing mastectomy in ptotic and large-sized breasts with two-stage reconstruction through transaxillary video-assisted technique: An effective surgical and anesthetic approach
IntroductionSkin-reducing mastectomy has been applied to several surgical techniques in which subcutaneous mastectomy is associated with various types of skin reduction, with preservation of a lower dermal flap to reinforce the inferior lateral seat of an implant. The aim of the study is to present a case series of patients with pendulous/ptotic and/or large-sized breasts treated for breast cancer at the Breast Surgery Unit of Istituto Nazionale Tumori IRCCS Fondazione âG. Pascaleâ, Naples, Italy, with the superomedial pedicle skin-reducing mastectomy technique, two-stage reconstruction, and transaxillary video-assisted technique, when a postoperative radiotherapy was indicated. We verified its effectiveness by discussing its results, especially in patients who are candidates for postmastectomy radiotherapy.Materials and methodsA single-center retrospective study was performed between January 2020 and March 2021 on a prospectively filled database of conservative mastectomies. Of the 64 patients who underwent nipple/skin-sparing mastectomies in the mentioned period, 17 (mean age 46â
years, range 30â62â
years) were treated with superomedial pedicle skin-reducing mastectomy, with two-stage breast reconstruction through transaxillary video-assisted replacement expander with definitive prosthesis and contralateral symmetrization, selected for postmastectomy radiotherapy.ResultsWe had only three minor complications. No flap necrosis, no infections, no breast seromas, and no reconstructive failures were observed. During follow-up of the patients treated with video-assisted reconstruction, there were no cases of infection, hematoma, implant rupture, or suture dehiscence in the reconstructed breast.DiscussionSkin-reducing mastectomy with superomedial pedicle is a safe and reliable procedure to treat breast cancer in selected patients, i.e., those with pendulous/ptotic and or large-sized breasts. Particularly, in patients who undergo postmastectomy radiotherapy, the two-stage reconstruction with video-assisted transaxillary endoscopic approach can find its main indication, using incisions positioned far from the mammary region, offering numerous advantages
Persistence of long-term COVID-19 sequelae in patients with cancer: An analysis from the OnCovid registry
Introduction: A significant proportion of patients with cancer who recover from Coronavirus Disease 2019 (COVID-19) may experience COVID-19 sequelae in the early post-infection phase, which negatively affect their continuity of care and oncological outcome. The long-term prevalence and clinical impact of the post-COVID-19 syndrome in patients with cancer are largely unknown. Methods: In this study, we describe the time course of COVID-19 sequelae in patients with non-advanced cancers enrolled in the OnCovid registry. Results: Overall, 186 patients were included, with a median observation period of 9.9 months (95%CI:8,8â11.3) post-COVID-19 resolution. After a median interval of 2.3 months post-COVID-19 (interquartile range: 1.4â3.7), 31 patients (16.6%) reported â„1 sequelae, including respiratory complications (14, 7.6%), fatigue (13, 7.1%), neuro-cognitive sequelae (7, 3.8%). The vast majority of the patients were not vaccinated prior to COVID-19. COVID-19-related sequelae persisted in 9.8% and 8% of patients 6 and 12 months after COVID-19 resolution. Persistence of sequelae at first oncological follow-up was associated with history of complicated COVID-19 (45.2% vs 24.8%, p = 0.0223), irrespective of oncological features at COVID-19 diagnosis. Conclusion: This study confirms for the first time that, in a largely unvaccinated population, post-COVID-19 syndrome can affect a significant proportion of patients with non-advanced cancer who recovered from the acute illness. COVID-19 sequelae may persist up to 12 months in some patients, highlighting the need for dedicated prevention and supportive strategies
- âŠ