1,104 research outputs found
Private Data System Enabling Self-Sovereign Storage Managed by Executable Choreographies
With the increased use of Internet, governments and large companies store and
share massive amounts of personal data in such a way that leaves no space for
transparency. When a user needs to achieve a simple task like applying for
college or a driving license, he needs to visit a lot of institutions and
organizations, thus leaving a lot of private data in many places. The same
happens when using the Internet. These privacy issues raised by the centralized
architectures along with the recent developments in the area of serverless
applications demand a decentralized private data layer under user control. We
introduce the Private Data System (PDS), a distributed approach which enables
self-sovereign storage and sharing of private data. The system is composed of
nodes spread across the entire Internet managing local key-value databases. The
communication between nodes is achieved through executable choreographies,
which are capable of preventing information leakage when executing across
different organizations with different regulations in place. The user has full
control over his private data and is able to share and revoke access to
organizations at any time. Even more, the updates are propagated instantly to
all the parties which have access to the data thanks to the system design.
Specifically, the processing organizations may retrieve and process the shared
information, but are not allowed under any circumstances to store it on long
term. PDS offers an alternative to systems that aim to ensure self-sovereignty
of specific types of data through blockchain inspired techniques but face
various problems, such as low performance. Both approaches propose a
distributed database, but with different characteristics. While the
blockchain-based systems are built to solve consensus problems, PDS's purpose
is to solve the self-sovereignty aspects raised by the privacy laws, rules and
principles.Comment: DAIS 201
The rank of trifocal grassmann tensors
Grassmann tensors arise from classical problems of scene reconstruction in computer vision. Trifocal Grassmann tensors, related to three projections from a projective space of dimension k onto view spaces of varying dimensions, are studied in this work. A canonical form for the combined projection matrices is obtained. When the centers of projections satisfy a natural generality assumption, such canonical form gives a closed formula for the rank of trifocal Grassmann tensors. The same approach is also applied to the case of two projections, confirming a previous result obtained with different methods in [M. Bertolini, G. Besana, and C. Turrini, Ann. Mat. Pura Appl. (4), 196 (2016), pp. 539-553]. The rank of sequences of tensors converging to tensors associated with degenerate configurations of projection centers is also considered, giving concrete examples of a wide spectrum of phenomena that can happen
On special quadratic birational transformations of a projective space into a hypersurface
We study transformations as in the title with emphasis on those having smooth
connected base locus, called "special". In particular, we classify all special
quadratic birational maps into a quadric hypersurface whose inverse is given by
quadratic forms by showing that there are only four examples having general
hyperplane sections of Severi varieties as base loci.Comment: Accepted for publication in Rendiconti del Circolo Matematico di
Palerm
Disposable versus reusable ureteroscopes. A prospective multicenter randomized comparison
Introduction: To compare reusable and disposable flexible ureteroscopes in terms of efficacy and safety for patients undergoing RIRS, with
specific reference to post-operative complications and infection rates. Materials and methods: Patients with a renal stone eligible for RIRS
were enrolled in this multicenter, randomized, clinical trial study. Patients were randomized into two groups: group A (90 patients) underwent RIRS with a reusable flexible ureteroscope and group B (90 patients) were treated with a disposable one. Results: The patients’ demographics, stones features and preoperative urine cultures were comparable between the groups. The SFRs were not significantly different (86,6% and 90,0% for group A and group B respectively, p = 0.11) and the mean cost for each procedure was comparable (2321 € in group A vs 2543 € in group B, p = 0.09). However, the days of hospitalization and of antibiotic therapy were higher in group A (p ≤ 0.05). The overall complication rate in group A was 8.8% whilst in group B it was 3.3% (p ≤ 0.05); in particular, group A exhibited a greater number of major complications (Clavien score IIIa-V). The overall postoperative infections rate was 16.6% in group A and 3.3% in group B (p ≤ 0.05). Furthermore, none of the patients in group B developed urosepsis or had a positive blood culture, while 3 patients in group A did (p < 0.05).
Conclusions: The use of disposable ureteroscopes is characterized by significantly lower post-operative complications and infection rates,
while having comparable costs and SFRs vis à vis reusable ureteroscopes
Ejaculation-sparing thulium laser enucleation of the prostate (ES-ThuLEP): outcomes on a large cohort
Purpose: To assess the effects of a new ejaculation-sparing thulium laser enucleation of the prostate (ES-ThuLEP) technique on sexual functions and micturition, in patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH) and to evaluate how the surgical technique of ES-ThuLEP can lead to ejaculation preservation. Methods: A prospective study was carried out between January 2015 and January 2018 on patients with surgical indication for BPH, who wished to preserve ejaculation. The patients were treated with ES-ThuLEP and were evaluated before and 3 and 6 months after surgery. Three validated questionnaires (ICIQ-MLUTSsex, IIEF-5 and IPSS) were used to assess changes in ejaculation, erectile function and urinary symptoms. Uroflowmetry (Qmax and Qavg), post-void residual volume and voided volume were also evaluated, to assess micturition improvement. Patients with moderate to severe erectile dysfunction were excluded. Statistical analysis was performed with the Student\u2019s t test, Chi-square test and logistic regression analysis. Results: Two hundred and eighty three patients were enrolled. Ejaculation was spared in 203 and 219 patients at 3 and 6 months after surgery. No significant differences were observed between erectile function before and after surgery: baseline IIEF-5 = 16.2 \ub1 4.47 vs 16.7 \ub1 2.9 (p = 0.419) and 17.7 \ub1 3.2 (p = 0.410) at 3 and 6 months. Significant improvement in urinary symptoms was achieved: baseline IPSS = 19.4 \ub1 7.24 vs 5.8 \ub1 4.3 (p = 0.032) and 3.9 \ub1 4.1 (p = 0.029) at 3 and 6 months. Conclusion: ES-ThuLEP effectively preserved ejaculation in over two thirds of the patients without compromising micturition improvement or erectile function. ES-ThuLEP could be a valid treatment option for BPH in young and sexually active men
A prospective multicenter randomized comparison between Holmium Laser Enucleation of the Prostate (HoLEP) and Thulium Laser Enucleation of the Prostate (ThuLEP)
Purpose: To compare intra and perioperative parameters between HoLEP and ThuLEP in the treatment of benign prostatic hyperplasia and to evaluate clinical and functional outcomes of the two procedures with a 12-month follow-up. Methods: A prospective randomized study was performed on 236 consecutive patients who underwent ThuLEP (n = 115), or HoLEP (n = 121) in three different centers. Intra and perioperative parameters were analyzed: operative time, enucleated tissue weight, irrigation volume, blood loss, catheterization time, hospital stay and complications. Patients were evaluated preoperatively and 3 and 12 months postoperatively with the international prostate symptom score (IPSS), the quality of life (QoL) score, post-void residual volume (PVR), PSA and maximum flow rate (Qmax). Results: Preoperative variables in each study arm did not show any significant difference. Compared to HoLEP, ThuLEP showed similar operative time (63.69 vs 71.66 min, p = 0.245), enucleated tissue weight (48.84 vs 51.13 g, p = 0.321), catheterization time (1.9 vs 2.0 days, p = 0.450) and hospital stay (2.2 vs 2.8 days, p = 0.216), but resulted in less haemoglobin decrease (0.45 vs 2.77 g/dL, p = 0.005). HoLEP presented a significantly higher number of patients with postoperative acute urinary retention and stress incontinence. No significant differences were found in PSA, Qmax, PVR, IPSS and QoL score during follow-up. Conclusion: ThuLEP and HoLEP both relieved lower urinary tract symptoms equally, with high efficacy and safety. ThuLEP detemined reduced blood loss and early postoperative complications. Catheterization time, enucleated tissue, hospital stay, operative time and follow-up parameters did not show any significant difference
Holmium laser enucleation of the prostate with Virtual Basket mode: faster and better control on bleeding
Background: To compare clinical intra and early postoperative outcomes between conventional Holmium laser enucleation of the prostate (HoLEP) and Holmium laser enucleation of the prostate using the Virtual Basket tool (VB-HoLEP) to treat benign prostatic hyperplasia (BPH). Methods: This prospective randomized study enrolled consecutive patients with BPH, who were assigned to undergo either HoLEP (n = 100), or VB-HoLEP (n = 100). All patients were evaluated preoperatively and postoperatively, with particular attention to catheterization time, operative time, blood loss, irrigation volume and hospital stay. We also evaluated the patients at 3 and 6 months after surgery and assessed maximum flow rate (Qmax), postvoid residual urine volume (PVR), the International Prostate Symptom Score (IPSS) and the Quality of Life score (QOLS). Results: No significant differences in preoperative parameters between patients in each study arm were found. Compared to HoLEP, VB-HoLEP resulted in less hemoglobin decrease (2.54 vs. 1.12 g/dl, P = 0.03) and reduced operative time (57.33 ± 29.71 vs. 42.99 ± 18.51 min, P = 0.04). HoLEP and VB-HoLEP detrmined similar catheterization time (2.2 vs. 1.9 days, P = 0.45), irrigation volume (33.3 vs. 31.7 l, P = 0.69), and hospital stay (2.8 vs. 2.7 days, P = 0.21). During the 6-month follow-up no significant differences in IPSS, Qmax, PVR, and QOLS were demonstrated. Conclusions: HoLEP and VB-HoLEP are both efficient and safe procedures for relieving lower urinary tract symptoms. VB-HoLEP was statistically superior to HoLEP in blood loss and operative time. However, procedures did not differ significantly in catheterization time, hospital stay, and irrigation volume. No significant differences were demonstrated in QOLS, IPSS, Qmax and PVR throughout the 6-month follow-up. Trial Registration: Current Controlled Trials ISRCTN72879639; date of registration: June 25th, 2015. Retrospectively registred
Sexually transmissible infections among young adolescents in Milan areas: a multicentre study
Objective: Sexually transmitted infections (STIs) are a major health problem affecting mostly young people, the exact magnitude of STIs is frequently unknown due to lack of country surveillance systems. Aim of this study was to determine the prevalence of STIs and relative risk factors among and adolescents in Milan areas, Italy. Methods: From May to October 2011, 117 adolescents (63 female, 54%), median age 15 years, attending hospitals from the north-western areas of Milan, Italy, were enrolled. All subjects completed a questionnaire and provided a urine sample, which was tested for Neisseria gonorrhea, Chlamidia trachomatis, Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum/parvum, Trichomonas vaginalis, Treponema pallidum, Streptococcus agalatiae, Haemophylus ducrey, Citomegalovirus (CMV), Herpes Simplex Virus 1(HSV1) and Lymphogranuloma venereum by a multiplex PCR assay: Seeplex\uae STI Master ACE Detection (Seegene, Seoul, Korea). Forty tree out of 117 adolescents (36%) were HIV-1 positive, 63% (74/117) were without any underlying infectious disease. Results: Fifty seven (48,7%) out of 117 adolescent were sexually active (SA), 20 out of 57 (35%) had STIs as follow: 24.5% (14 cases) U.urealyticum/parvum, 7% (4cases) C.trachomatis, 1.7% (one case each) M. genitalium and N.gonorrhoea. Thirty-two (56%) out of 57 SA adolescents were HIV-1 positive and infected with U. urealyticum/parvum (37.5%, 12 cases) and C.trachomatis (6.2% 2 cases). A single case (3.1%) of mixed infection due to C.trachomatis, N.gonorrhoea and U.urealyticum/parvum was observed. Six out of 60 (10%) sexually inactive (SI) adolescents resulted positive for U.urealyticum/parvum (3 cases), C.trachomatis (2 cases) and N.gonorrhoea (1 case). Eleven out of 60 were HIV-1 positive and among this group one case of C.trachomatis and U.urealyticum/parvum infection was reported. For T.vaginalis, T. pallidum, S. agalatiae, H.ducrey, CMV, HSV1 and Lymphogranuloma venereum any infection was reported. Conclusion: STIs as expected were higher in SA adolescent than in SI and in HIV-1 positive patients (P <0.025).Twenty-two percent of SA adolescents resulted positive for at least one STIs. A prevalence of 14.5% (17/117) for U. urealyticum/parvum, was detected in the adolescents studied, even if its clinical significance has yet to be assessed. Findings suggest that surveillance and screening programs should be implemented to prevent sequels on this vulnerable population
A comparison among PCNL, Miniperc and Ultraminiperc for lower calyceal stones between 1 and 2 cm: A prospective, comparative, multicenter and randomised study
Background: Conventional Percutaneous Lithotripsy (PCNL) has been an effective, successful and easy approach for especially > 1 cm sized calyceal stones however risks of complications and nephron loss are inevitable. Our aim is to compare the efficacy and safety of PCNL, MiniPerc (MP) and UltraMiniPerc (UMP) for lower calyceal stones between 1 and 2 cm with a multicenter prospective randomized study. Methods: Between January 2015 and June 2018, 132 consecutive patients with single lower calyceal stone were enrolled. Patients were randomized in three groups; A: PCNL; B: MP; C: UMP. 44 patients for the Group A, 47 for Group B and 41 for Group C. Exclusion criterias were the presence of coagulation impairments, age of < 18 or > 75, presence of infection or serious comorbidities. Patients were controlled with computerized tomography scan after 3 months. A negative CT or an asymptomatic patient with stone fragments < 3 mm size were the criteria to assess the stone-free status. Patient characteristics, stone free rates (SFR) s, complications and re-treatment rates were analyzed. Results: The mean stone size were 16.38, 16.82 and 15.23 mm respectively in Group A, B and C(p = 0.34). The overall SFR was significantly higher in Group A (86.3%) and B (82.9%) as compared to Group C (78%)(p < 0.05). The re-treatment rate was significantly higher in Group C (12.1%) and complication rates was higher in Group A (13.6%) as compared to others(p < 0.05). The hospitalization was significantly shorter in Group C compared to Group A (p = 0.04). Conclusions: PCNL and MP showed higher efficacy than UMP to obtain a better SFR. Auxiliary and re-treatment rates were higher in UMP. On the other hand for such this kind of stones PCNL had more complications. Overall evaluation favors MP as a better indication in stones 1-2 cm size
Compilation of parameterized seismogenic sources in Iberia for the SHARE European-scale seismic source model.
Abstract: SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded project (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are compiling a fully-parameterized active fault database for Iberia and the nearby offshore region. The principal goal of this initiative is for fault sources in the Iberian region to be represented in SHARE and incorporated into the source model that will be used to produce seismic hazard maps at the European scale. The SHARE project relies heavily on input from many regional experts throughout the Euro-Mediterranean region. At the SHARE regional meeting for Iberia, the 2010 Working Group on Iberian Seismogenic Sources (WGISS) was established; these researchers are contributing to this large effort by providing their data to the Iberian regional integrators in a standardized format. The development of the SHARE Iberian active fault database is occurring in parallel with IBERFAULT, another ongoing effort to compile a database of active faults in the Iberian region.
The SHARE Iberian active fault database synthesizes a wide range of geological and geophysical observations on active seismogenic sources, and incorporates existing compilations (e.g., Cabral, 1995; Silva et al., 2008), original data contributed directly from researchers, data compiled from the literature, parameters estimated using empirical and analytical relationships, and, where necessary, parameters derived using expert judgment. The Iberian seismogenic source model derived for SHARE will be the first regional-scale source model for Iberia that includes fault data and follows an internationally standardized approach (Basili et al., 2008; 2009). This model can be used in both seismic hazard and risk analyses and will be appropriate for use in Iberian- and European-scale assessments
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