678 research outputs found
Coverage and Deployment Analysis of Narrowband Internet of Things in the Wild
Narrowband Internet of Things (NB-IoT) is gaining momentum as a promising
technology for massive Machine Type Communication (mMTC). Given that its
deployment is rapidly progressing worldwide, measurement campaigns and
performance analyses are needed to better understand the system and move toward
its enhancement. With this aim, this paper presents a large scale measurement
campaign and empirical analysis of NB-IoT on operational networks, and
discloses valuable insights in terms of deployment strategies and radio
coverage performance. The reported results also serve as examples showing the
potential usage of the collected dataset, which we make open-source along with
a lightweight data visualization platform.Comment: Accepted for publication in IEEE Communications Magazine (Internet of
Things and Sensor Networks Series
Positioning by multicell fingerprinting in urban NB-IoT networks
Narrowband Internet of Things (NB-IoT) has quickly become a leading technology in the deployment of IoT systems and services, owing to its appealing features in terms of coverage and energy efficiency, as well as compatibility with existing mobile networks. Increasingly, IoT services and applications require location information to be paired with data collected by devices; NB-IoT still lacks, however, reliable positioning methods. Time-based techniques inherited from long-term evolution (LTE) are not yet widely available in existing networks and are expected to perform poorly on NB-IoT signals due to their narrow bandwidth. This investigation proposes a set of strategies for NB-IoT positioning based on fingerprinting that use coverage and radio information from multiple cells. The proposed strategies were evaluated on two large-scale datasets made available under an open-source license that include experimental data from multiple NB-IoT operators in two large cities: Oslo, Norway, and Rome, Italy. Results showed that the proposed strategies, using a combination of coverage and radio information from multiple cells, outperform current state-of-the-art approaches based on single cell fingerprinting, with a minimum average positioning error of about 20 m when using data for a single operator that was consistent across the two datasets vs. about 70 m for the current state-of-the-art approaches. The combination of data from multiple operators and data smoothing further improved positioning accuracy, leading to a minimum average positioning error below 15 m in both urban environments
Ultra wide band receiver based on turbo-equalization
La technologie de l'Ultra-Large-bande (UWB) est actuellement étudiée comme une solution utile pour les systÚmes de communications sans fil de grande capacité. Le rapport élevé de la largeur de bande du signal à la largeur de bande de l'information rend la technologie d'UWB attrayante pour des applications d'accÚs multiple. La synchronisation et l'égalization du canal sont les questions cruciales dans le développement de la technologie d'UWB, dû à la courte durée des signaux transmises. Dans cette contribution, nous proposons un turbo-égaliseur pour des récepteurs d'UWB, afin d'améliorer l'exécution de l'approche conventionnelle (récepteur RAKE). En particulier, les résultats obtenus ont démontré un perfectionnement d'exécution, en termes de taux d'erreurs sur les bits, avec une complexité computationelle menable
Myo-inositol may prevent gestational diabetes onset in overweight women: a randomized, controlled trial
Objective: To evaluate whether myo-inositol supplementation may reduce gestational diabetes mellitus (GDM) rate in overweight women. Methods: In an open-label, randomized trial, myo-inositol (2 g plus 200 ÎŒg folic acid twice a day) or placebo (200 ÎŒg folic acid twice a day) was administered from the first trimester to delivery in pregnant overweight non-obese women (pre-pregnancy body mass index â„ 25 and < 30 kg/m2). The primary outcome was the incidence of GDM. Results: From January 2012 to December 2014, 220 pregnant women were randomized at two Italian University hospitals, 110 to myo-inositol and 110 to placebo. The incidence of GDM was significantly lower in the myo-inositol group compared to the placebo group (11.6% versus 27.4%, respectively, p = 0.004). Myo-inositol treatment was associated with a 67% risk reduction of developing GDM (OR 0.33; 95% CI 0.15â0.70). Conclusions: Myo-inositol supplementation, administered since early pregnancy, reduces GDM incidence in overweight non-obese women
Treatment continuation and satisfaction in women using combined oral contraception with nomegestrol acetate and oestradiol: a multicentre, prospective cohort study (BOLERO)
Objective: The aim of the study was to examine treatment continuation and satisfaction over 1 year among women receiving nomegestrol acetate (NOMAC)/oestradiol (E2) combined oral contraception (COC) in real-world clinical practice. Methods: The 17 beta-Estradiol and Nomegestrol Acetate (BOLERO) Study is an observational, non-interventional, prospective, multicentre cohort study of premenopausal women (aged 18-50 years) who received prescription NOMAC/E2 (2.5 mg/1.5 mg) for contraception during routine clinical practice. Assessments were carried out at enrolment and at 3, 6 and 12 months. Probability of treatment continuation through 12 months (primary outcome) was examined using Kaplan-Meier survival analysis. Secondary outcomes included treatment satisfaction, menstrual cycle-related symptoms, libido and adverse events (AEs). Results: Of 298 enrolled women, 292 were evaluable. The probability of NOMAC/E2 continuation through 12 months was 73.7% (95% confidence interval [CI] 68.0%, 78.5%). Satisfaction with NOMAC/E2 increased from 56.9% (37/65) of women at initial evaluation to 89.2% (58/65) of women at 12 months. Physician ratings at 12 months showed satisfactory to very satisfactory in 84.0% (168/200) of women. Libido was not affected. Menstrual cycle-related symptoms significantly declined from enrolment (6.04 +/- 4.32) to 3 months (3.25 +/- 3.05) and 12 months (2.62 +/- 2.74; p < .0001). Treatment-related AEs were reported by 38.7% (113/292) of women. Conclusion: The real-world experience of women receiving NOMAC/E2 indicated very good treatment continuation, high satisfaction and significantly improved menstrual cycle-related symptoms
MicroRNA Expression in the Aqueous Humor of Patients with Diabetic Macular Edema.
We identified and compared secreted microRNA (miRNA) expression in aqueous humor (AH) and plasma samples among patients with: type 2 diabetes mellitus (T2D) complicated by non-proliferative diabetic retinopathy (DR) associated with diabetic macular edema (DME) (DME group: 12 patients); T2D patients without DR (D group: 8 patients); and non-diabetic patients (CTR group: 10 patients). Individual patient AH samples from five subjects in each group were profiled on TaqMan Low Density MicroRNA Array Cards. Differentially expressed miRNAs identified from profiling were then validated in single assay for all subjects. The miRNAs validated in AH were then evaluated in single assay in plasma. Gene Ontology (GO) analysis was conducted. From AH profiling, 119 mature miRNAs were detected: 86 in the DME group, 113 in the D group and 107 in the CTR group. miRNA underexpression in the DME group was confirmed in single assay for let-7c-5p, miR-200b-3p, miR-199a-3p and miR-365-3p. Of these four, miR-199a-3p and miR-365-3p were downregulated also in the plasma of the DME group. GO highlighted 54 validated target genes of miR-199a-3p, miR-200b-3p and miR-365-3p potentially implied in DME pathogenesis. Although more studies are needed, miR-200b-3p, let-7c-5p, miR-365-3p and miR-199a-3p represent interesting molecules in the study of DME pathogenesis
Mucinous and Signet-Ring Cell Colonic Adenocarcinoma in Inflammatory Bowel Disease: A Case-Control Study
Simple Summary Chronic active inflammation is a known risk factor for colorectal cancer (CRC) in inflammatory bowel disease (IBD), while the adenoma-carcinoma sequence appears to be associated with sporadic CRC. In the general population, mucinous and signet-ring cell adenocarcinomas are characterized by a worse prognosis. In IBD, a higher frequency of these CRC histotypes has been reported. In the present study, we investigated the frequency and characteristics of mucinous and signet-ring cell adenocarcinomas in patients with IBD versus age-matched non-IBD Controls. CRC was more frequently represented by mucinous/signet-ring cell adenocarcinoma in IBD than in Controls. In rectal CRC, there was a higher proportion of mucinous/signet-ring cell adenocarcinoma vs. standard adenocarcinoma in IBD but not in non-IBD Controls. No risk factors for these two CRC histotypes were identified in IBD. Present findings support that the frequency of mucinous/signet-ring cell colorectal adenocarcinoma is higher in IBD, being associated with rectal involvement of CRC. A higher frequency of mucinous and signet-ring cell colonic adenocarcinoma has been reported in inflammatory bowel disease (IBD). The primary aim was to investigate the frequency of mucinous and signet-ring cell colorectal adenocarcinoma in patients with IBD (Cases) versus age-matched non-IBD Controls. The secondary aims were to compare the characteristics of these two histotypes of colorectal cancer (CRC) in IBD patients vs. Controls and to search for specific risk factors in IBD. In a case-control study, all IBD patients with CRC diagnosed from 2000 to 2022 were enrolled and matched for age (1:2) with non-IBD Controls with CRC. The study population included 120 CRC patients (40 IBD, 80 Controls). In IBD, CRC included standard adenocarcinoma in 23 (57.5%) patients mucinous/signet-ring cell adenocarcinoma in 17 (42.5%) patients. The proportion of mucinous/signet-ring cell adenocarcinoma was higher in IBD than in Controls (17 [42.5%] vs. 18 [22.5%]; p = 0.03). In rectal CRC, the proportion of mucinous/signet-ring cell adenocarcinoma was higher than standard adenocarcinoma in IBD (8 [47.1%] vs. 4 [17.4%]; p = 0.04) but not in Controls (4 [22.2%] vs. 20 [32.2%]; p = 0.59). In rectal CRC, the proportion of these two histotypes was higher in Cases than in Controls (8/12 [66.6%] vs. 4/24 [16.6%]; p = 0.008), with no risk factors identified in IBD. CRC was more frequently represented by mucinous/signet-ring cell adenocarcinoma in IBD than in age-matched non-IBD Controls. In IBD, these two CRC histotypes were more frequent in the rectum
Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles - II. CO line survey of evolved stars: derivation of mass-loss rate formulae
We aim to (1) set up simple and general analytical expressions to estimate
mass-loss rates of evolved stars, and (2) from those calculate estimates for
the mass-loss rates of asymptotic giant branch (AGB), red supergiant (RSG), and
yellow hypergiant stars in our galactic sample. Rotationally excited lines of
CO are a very robust diagnostic in the study of circumstellar envelopes (CSEs).
When sampling different layers of the CSE, observations of these molecular
lines lead to detailed profiles of kinetic temperature, expansion velocity, and
density. A state-of-the-art, nonlocal thermal equilibrium, and co-moving frame
radiative transfer code that predicts CO line intensities in the CSEs of
late-type stars is used in deriving relations between stellar and
molecular-line parameters, on the one hand, and mass-loss rate, on the other.
We present analytical expressions for estimating the mass-loss rates of evolved
stellar objects for 8 rotational transitions of the CO molecule, apply them to
our extensive CO data set covering 47 stars, and compare our results to those
of previous studies. Our expressions account for line saturation and resolving
of the envelope, thereby allowing accurate determination of very high mass-loss
rates. We argue that, for estimates based on a single rotational line, the
CO(2-1) transition provides the most reliable mass-loss rate. The mass-loss
rates calculated for the AGB stars range from 4x10^-8 Msun/yr up to 8x10^-5
Msun/yr. For RSGs they reach values between 2x10^-7 Msun/yr and 3x10^-4
Msun/yr. The estimates for the set of CO transitions allow time variability to
be identified in the mass-loss rate. Possible mass-loss-rate variability is
traced for 7 of the sample stars. We find a clear relation between the
pulsation periods of the AGB stars and their derived mass-loss rates, with a
levelling off at approx. 3x10^-5 Msun/yr for periods exceeding 850 days.Comment: Accepted for publication by Astronomy and Astrophysics, 24 pages + 28
pages appendix, 20 figure
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