Hemorheological abnormalities in human arterial hypertension

Presti, Rosalia Lo,Hopps, Eugenia,Caimi, Gregorio 한국유변학회 2014 Korea-Australia rheology journal Vol.26 No.2

Blood rheology is impaired in hypertensive patients. The alteration involves blood and plasma viscosity, and the erythrocyte behaviour is often abnormal. The hemorheological pattern appears to be related to some pathophysiological mechanisms of hypertension and to organ damage, in particular left ventricular hypertrophy and myocardial ischemia. Abnormalities have been observed in erythrocyte membrane fluidity, explored by fluorescence spectroscopy and electron spin resonance. This may be relevant for red cell flow in microvessels and oxygen delivery to tissues. Although blood viscosity is not a direct target of antihypertensive therapy, the rheological properties of blood play a role in the pathophysiology of arterial hypertension and its vascular complications.

Hemorheological abnormalities in human arterial hypertension

Rosalia Lo Presti,Eugenia Hopps,Gregorio Caimi 한국유변학회 2014 Korea-Australia rheology journal Vol.26 No.2

Blood rheology is impaired in hypertensive patients. The alteration involves blood and plasma viscosity, andthe erythrocyte behaviour is often abnormal. The hemorheological pattern appears to be related to somepathophysiological mechanisms of hypertension and to organ damage, in particular left ventricular hypertrophyand myocardial ischemia. Abnormalities have been observed in erythrocyte membrane fluidity,explored by fluorescence spectroscopy and electron spin resonance. This may be relevant for red cell flowin microvessels and oxygen delivery to tissues. Although blood viscosity is not a direct target of antihypertensivetherapy, the rheological properties of blood play a role in the pathophysiology of arterialhypertension and its vascular complications.

The Role of False Tendons in Left Ventricular Remodeling and Secondary Mitral Regurgitation After Acute Myocardial Infarction

Saberio Lo Presti,Diego Lugo Baruqui,Jorge Perez,Ben Johns Vadasseril,Esteban Escolar,Sofia A. Horvath,Christos G. Mihos 한국심초음파학회 2021 Journal of Cardiovascular Imaging (J Cardiovasc Im Vol.29 No.1

BACKGROUND: Left ventricular false tendons (LVFT) are common structures visualized on transthoracic echocardiography (TTE). The present study tested the hypothesis that LVFT, via a possible ‘constraint’ mechanism, attenuate left ventricular (LV) remodeling and secondary mitral regurgitation after acute myocardial infarction. METHODS: Seventy-one patients admitted to the Coronary Care Unit following an ST-elevation (n = 63) or non-ST-elevation (n = 8) myocardial infarction were analyzed; 29 (41%) had LVFT, and 42 (59%) did not (no-LVFT). All had a TTE and at least 1 follow-up study after revascularization. The χ2 analysis, Student's t-test, and Mann Whitney U test were used for the statistical analyses. RESULTS: The mean age (64 vs. 66 years), left ventricular ejection fraction (LVEF) (41% vs. 39%), left ventricular end-diastolic diameter (LVEDd) index (23 mm/m2 for both), and prevalence of ≥ moderate secondary/functional mitral regurgitation (MR) (17% vs. 14%) were similar between the LVFT and no-LVFT groups. At 1-year follow-up, there was no significant difference in chamber remodeling amongst the LVFT versus no-LVFT group when assessed by: 1) ≥ 10% decrease in the relative LVEF (24% vs. 26%; p = 0.83); 2) ≥ 10% increase in the LVEDd index (41% vs. 38%, p = 0.98); and, 3) ≥ 10% increase in the LV mass index (48% vs. 41%, p = 0.68). There was no difference in the prevalence of ≥ moderate secondary/functional MR (17% vs. 12%, p = 0.77). Outcomes remained similar when stratifying by LVFT morphology or ischemic territory. CONCLUSIONS: In patients with mild to moderate LV dysfunction and normal chamber size, LVFT do not affect the development of LV remodeling or secondary/functional MR post-myocardial infarction.

GNSS spoofing detection: Theoretical analysis and performance of the Ratio Test metric in open sky

Jie Huang,Letizia Lo Presti,Beatrice Motella,Marco Pini 한국통신학회 2016 ICT Express Vol.2 No.1

Nowadays more and more applications rely on the information provided by Global Navigation Satellite Systems (GNSSs), but the vulnerability of GNSS signals to interference, jamming and spoofing is a growing concern. Among all the possible sources of intentional interference, spoofing is extremely deceptive and sinister. In fact, the victim receiver may not be able to warn the user and discern between authentic and false signals. For this reason, a receiver featuring spoofing detection capabilities might become a need in many cases. Different types of spoofing detection algorithms have been presented in recent literature. One of the first, referred to as Ratio Metric, allows for the monitoring of possible distortions in the signal correlation. The effectiveness of the Ratio Test has been widely discussed and demonstrated, while in this paper we analyze its performance, proposing a mathematical model that is used to assess the false alarm and detection probabilities.

“YOU POST, I TRAVEL”. THE INFLUENCE OF TRAVEL BLOGGER CREDIBILITY, MOTIVATION AND ENGAGEMENT ON FOLLOWERS’ TRAVEL DECISIONS. A TWO-COUNTRY SURVEY.

Giada Mainolfi,Letizia Lo Presti,Vittoria Marino 글로벌지식마케팅경영학회 2020 Global Marketing Conference Vol.2020 No.11

Blogging has become a global phenomenon thanks to the persuasive role gained by a number of bloggers who have reached a high level of recognition and trust to the point of becoming key opinion leaders. Travel is included among the most relevant topics together with fashion and food (Websitehub, 2019). Millions of individuals have joined travel blogs to search for information and also to share their travel experiences online. A tourism product can be included among “experience goods” meaning that it is the result of a bundle of services and experiences, which are hard to evaluate before the purchase. Thus, the suggestions from other travellers who have already experienced a specific tourist destination and are able to tell the experience in a sincere and trustworthy way will become – with a high probability – the preferred source of pre-purchase information and also the most influential in travel decision making (Crotts, 1999). Therefore, travel blogging is definitely become a part of the tourist production and consumption process (Bosangit et al., 2012). However, the proliferation and diversity of blogs together with the absence of a real expertise raise the question about the role exerted by the blogger credibility on behavioural intentions of the readers. However, despite the fact that travel blogs and bloggers are gaining popularity in the blogosphere, also attracting the attention of marketing scholars (Metz, 2016; Cosenza et al., 2014), the literature review has highlighted some scientific gaps regarding the role of credibility and engagement within the blog in terms of traveller behaviour consequences. Such gaps call for further research. Starting from the above considerations, the study aims at contributing to the current knowledge on blogger credibility in terms of the potential impacts exerted by thetravel blog on behavioural consequences from interactions between credibility, motivations and engagement on post-reading travel intentions and e-WOM.

Efficiency Enhancement of mm-Wave Power Amplifiers Using Envelope Tracking

Yan, J J,Presti, C D,Kimball, D F,Young-Pyo Hong,Chin Hsia,Asbeck, P M,Schellenberg, J IEEE 2011 IEEE microwave and wireless components letters Vol.21 No.3

<P>This letter presents a 44 GHz GaAs MMIC-based power amplifier (PA) which uses envelope tracking (ET) techniques for efficiency enhancement. Digital pre-distortion (DPD) is also employed to achieve high linearity. For a 7.6 dB PAPR 64QAM 20 MHz bandwidth signal (data rate 120 Mb/s) at an output power of 23.8 dBm, the measured EVM was 2.0% and ACPR1 was better than -40 dBc. Power efficiency enhancement of more than 5.7 times for the final MMIC stage (from 1.22% to 7%) was measured, using an external drain modulator. To the authors' best knowledge, this is the first time envelope tracking has been applied to PAs in the millimeter wave regime.</P>

Kalman filter-based ARAIM algorithm for integrity monitoring in urban environment

Hieu Trung Tran,Letizia Lo Presti 한국통신학회 2019 ICT Express Vol.5 No.1

This work proposes an adaptation of Advanced Receiver Autonomous Integrity Monitoring (ARAIM) algorithm for snapshot integrity monitoring in urban environment, using Kalman Filter (KF) as underlying positioning method. This new method can follow the changes of signal quality, maintaining good performance under the effect of multipath which is always presents in urban areas. Performance analysis using both simulated and real data validates the method, and comparison with conventional ARAIM algorithm (which was developed for aviation) further consolidates the suitability of the proposed method for urban scenario.

High Power Digitally-Controlled SOI CMOS Attenuator With Wide Attenuation Range

Jinho Jeong,Pornpromlikit, Sataporn,Scuderi, Antonino,Presti, Calogero,Asbeck, Peter IEEE 2011 IEEE microwave and wireless components letters Vol.21 No.8

<P>An attenuator is presented in a 0.13 μm silicon-on-insulator (SOI) CMOS technology, to be used for power control of RF wireless transmitters. The design is based on a T-network consisting of two series switches and 63 shunt switches. A gate switching technique is utilized in the series switches for high power handling and high isolation. Measurements at 1.88 GHz show that the minimum insertion loss is as low as 0.6 dB and maximum attenuation is 55.3 dB with worst input return loss of 8.1 dB. The attenuation can be digitally controlled in steps of around 1 dB. The 1 dB gain compression point is as high as 21.0 dBm in the through mode.</P>

Design of a Wideband High-Voltage High-Efficiency BiCMOS Envelope Amplifier for Micro-Base-Station RF Power Amplifiers

Myoungbo Kwak,Kimball, D. F.,Presti, C. D.,Scuderi, A.,Santagati, C.,Yan, J. J.,Asbeck, P. M.,Larson, L. E. IEEE 2012 IEEE transactions on microwave theory and techniqu Vol.60 No.6

<P>A high-performance bipolar-CMOS-DMOS (BCD) monolithic envelope amplifier for micro-base-station power amplifiers (PAs) is presented. Measurement of the BCD high-voltage (<I>V</I><SUB>DD</SUB> = 15 V) envelope amplifier shows an efficiency of 72% using 7.7-dB peak-to-average ratio WCDMA input signals at an average envelope amplifier output power above 3 W. A WCDMA envelope-tracking RF PA at 2.14 GHz, including a GaN field-effect transistor RF stage, has an overall drain efficiency above 51%, with a normalized power root-mean-square error below 1.2% and an adjacent channel leakage ratio of -49 dBc at 5-MHz offset using memory-effect mitigation digital pre-distortion, at an average output power above 2 W and a gain of 10 dB.</P>

Characterization of human infiltrating and circulating gamma-delta T cells in prostate cancer

Marco Vella,Daniela Coniglio,Alberto Abrate,Cristina Scalici Gesolfo,Elena Lo Presti,Serena Meraviglia,Vincenzo Serretta,Alchiede Simonato 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.2

Purpose: The aim of our study was to prospectively evaluate the distribution of gamma-delta (γδ)1 and γδ2 T cells and their phenotypes in peripheral blood and prostate samples of patients diagnosed with or without prostate cancer (PCa) at prostate biopsy. Materials and Methods: A consecutive series of 43 outpatients underwent trans-rectal echo-guided prostate biopsy for suspected PCa. Flow cytometry analysis was used to identify and characterize the γδ T cells populations in peripheral blood and tissue samples. Patients were stratified according to the presence or not of PCa, and its International Society of Urological Pathology (ISUP) grade (1 vs. ≥2). Results: The distribution of γδ T cells in peripheral blood and prostate tissue showed wide variability and non-significant differences. A slightly higher percentage of δ2 T cells and a slightly lower percentage of δ1 T cells were found in peripheral blood of cancer patients. A non-significantly higher percentage of both Vδ1 and Vδ2 was expressed in cancer tissues, but a trend for lower distribution of δ1 and δ2 T cells was observed in ISUP grade ≥2. The “central memory” and “effector memory” were the most expressed T cells phenotype in peripheral blood and tissue samples. However no substantial differences in T cells subtypes distribution between cancer and healthy tissue were observed. Conclusions: No substantially different percentages of γδ T cells were found in peripheral blood and biopsy samples of healthy and PCa patients. However a non-significant trend for lower infiltrate in higher ISUP grade cancer tissue was observed, suggesting a possible role for the immunosurveillance of PCa.