70 research outputs found
LivDet 2017 Fingerprint Liveness Detection Competition 2017
Fingerprint Presentation Attack Detection (FPAD) deals with distinguishing
images coming from artificial replicas of the fingerprint characteristic, made
up of materials like silicone, gelatine or latex, and images coming from alive
fingerprints. Images are captured by modern scanners, typically relying on
solid-state or optical technologies. Since from 2009, the Fingerprint Liveness
Detection Competition (LivDet) aims to assess the performance of the
state-of-the-art algorithms according to a rigorous experimental protocol and,
at the same time, a simple overview of the basic achievements. The competition
is open to all academics research centers and all companies that work in this
field. The positive, increasing trend of the participants number, which
supports the success of this initiative, is confirmed even this year: 17
algorithms were submitted to the competition, with a larger involvement of
companies and academies. This means that the topic is relevant for both sides,
and points out that a lot of work must be done in terms of fundamental and
applied research.Comment: presented at ICB 201
On the interoperability of capture devices in fingerprint presentation attacks detection
Abstract A presentation attack consists in submitting to the fingerprint capture device an artificial replica of the finger of the targeted client. If the sensor is not equipped with an appropriate algorithm aimed to detect the fingerprint spoof, the system processes the obtained image as a one belonging to a real fingerprint. In order to face this problem, several presentation attacks detection (PAD) algorithms have been proposed so far. Current methods heavily rely on features extracted from a large data set of fake and real fingerprint images, and an appropriate classifier trained with such data to distinguish between live (real) and fake (spoof) fingerprint images. Building such data set requires a significant effort for fabricating samples of fake fingerprints, with the most effective materials used to circumvent the sensor. Interesting and promising results have been obtained, but they also suggest that the PAD is tailored on the particular sensor. Small and significant differences also occur when a novel version of the same sensor is released, and this may affect the PAD. Therefore, making a PAD interoperable is among the main current issues when considering fingerprints as the first level of protection and security of logical or physical resources. This paper is a first attempt to assess at which extent the sensor interoperability can be an issue for fingerprint PADs and to eventually propose a solution to this limitation. In particular, textural features will be under focus and a feature space transformation method based on the least square is proposed
Gastric adenocarcinoma cutaneous metastasis arising at a previous surgical drain site: a case report
<p>Abstract</p> <p>Introduction</p> <p>Skin metastasis from internal carcinoma rarely occurs. It has an incidence of 0.7 to 9% and it may be the first sign of an unknown malignancy. However, it can also occur during follow-up.</p> <p>Case presentation</p> <p>A 90-year-old female patient was admitted to our surgical division with a diagnosis of anemia from a bleeding gastric adenocarcinoma. She underwent a gastric resection and Billroth II retrocolic Hofmeister/Finsterer reconstruction. She developed an enteric fistula, which needed a permanent abdominal drain until the 60<sup>th </sup>postoperative day. After 12 months she was readmitted to our division with subacute small bowel obstruction and an erythematous swelling on the right side of the abdomen. Biopsies characterized it as a cutaneous metastasis from the gastric adenocarcinoma. No surgical therapy was performed given her poor clinical condition.</p> <p>Conclusion</p> <p>Skin metastasis from carcinomas of the upper gastrointestinal tract is very rare. Persisting erythematous nodules must be biopsied in order to diagnose cutaneous metastases and to recognize them early and start prompt therapy with anti-tumour agents before the occurrence of massive visceral metastases.</p
Photoexcitations and Emission Processes in Organometal Trihalide Perovskites
Organometal halide perovskites have recently attracted widespread attention among scientists, as they combine the advantages of low-cost processability with strong light absorption, band-gap tunability from the near-infrared to the visible region of the electromagnetic spectrum, efficient light emission and charge transport. Such combination of features is unique among solution-processed materials and makes perovskites appealing for several optoelectronic applications, in particular those related to energy sustainability, which could help the advent of a new generation of low-cost but efficient solar cells and large-area light-emitting devices.This chapter reports a critical review of the efforts that scientists have made until now to understand the photophysics of organometal halide perovskites. We address the ongoing debate on the nature of the photoexcited species, namely the role played by free carriers and excitons, the determination of the exciton binding energy as a measure of the Coulomb interaction strength in these materials, the competition between radiative and non-radiative processes, the role and density of charge carrier traps, and last but not least a critical analysis of those phenomena at the base of laser action, highlighting the most relevant results and possible solutions to issues that still remain open
Survival as a clinical outcome and its spiritual significance in a cohort of patients with advanced central pelvic neoplastic disease undergoing total pelvic evisceration: a poorly debated issue
Background Patients with either treatment-resistant or relapsing advanced central pelvic neoplastic disease present with a condition responsible for debilitating symptoms and consequently poor quality of life (QoL). For these patients, therapeutic strategies are very limited and total pelvic evisceration is the only option for relieving the symptoms and increasing survival. Of note, taking charge of these patients cannot be limited to increasing their lifespan but must also be aimed at improving the clinical, psychological, and spiritual conditions. This study aimed to prospectively evaluate the improvement in survival and QoL, focusing on spiritual wellbeing (SWB), in patients with poor life expectancy who underwent total pelvic evisceration for advanced gynecological cancers at our center. Patients and methodsThe QoL and SWB were assessed using the European Organisation for Research and Treatment of Cancer QoL questionnaire (EORTC QLQ-C30), EORTC QLQ-SWB32, and SWB scale, which were repeatedly administered: 30 days before surgery, 7 days after the procedure, 1 and 3 months after surgery, and then every 3 months until death or the last follow-up assessment. Operative outcomes (blood loss, operative time, hospitalization, and incidence of complications) were evaluated as secondary endpoints. The patients and their families were included in a dedicated psycho-oncological and spiritual support protocol, which was managed by specifically trained and specialized personnel who accompanied them during all phases of the study. ResultsA total of 20 consecutive patients from 2017 to 2022 were included in this study. Of these patients, 7 underwent total pelvic evisceration by laparotomy and 13 underwent laparoscopy. The median survival was 24 months (range: 1-61 months). After a median follow-up of 24 months, 16 (80%) and 10 patients (50%) were alive at 1 year and 2 years after surgery, respectively. The EORTC-QLQ-C30 scores significantly improved yet at 7 days and at 1, 3, 6, and 12 months, as compared with the preoperative values. In particular, an early improvement in pain, overall QoL, and physical and emotional functions was observed. With respect to the SWB, the global SWB item score of the EORTC QLQ-SWB32 questionnaire significantly increased after 1 month and 3 months, as compared with preoperative values (p = 0.0153 and p = 0.0018, respectively), and remained stable thereafter. The mean SWB scale score was 53.3, with a sense of low overall SWB in 10 patients, a sense of moderate SWB in eight patients, and a sense of high SWB in two patients. The SWB scale score significantly increased after 7 days, 1 month, and 3 months, as compared with the preoperative value (p = 0202, p = 0.0171, and p = 0.0255, respectively), and remained stable thereafter. ConclusionTotal pelvic evisceration is a valid approach for improving both survival and QoL in selected patients with advanced pelvic neoplasms and poor life expectancy. Our results particularly underline the importance of accompanying the patients and their families during the journey with dedicated psychological and spiritual support protocols
Mitochondrial DNA Regionalism and Historical Demography in the Extant Populations of Chirocephalus kerkyrensis (Branchiopoda: Anostraca)
Background: Mediterranean temporary water bodies are important reservoirs of biodiversity and host a unique assemblage of diapausing aquatic invertebrates. These environments are currently vanishing because of increasing human pressure.
Chirocephalus kerkyrensis is a fairy shrimp typical of temporary water bodies in Mediterranean plain forests and has
undergone a substantial decline in number of populations in recent years due to habitat loss. We assessed patterns of genetic connectivity and phylogeographic history in the seven extant populations of the species from Albania, Corfu Is. (Greece), Southern and Central Italy.
Methodology/Principal Findings: We analyzed sequence variation at two mitochondrial DNA genes (Cytochrome Oxidase I and 16s rRNA) in all the known populations of C. kerkyrensis. We used multiple phylogenetic, phylogeographic and coalescence-based approaches to assess connectivity and historical demography across the whole distribution range of the species. C. kerkyrensis is genetically subdivided into three main mitochondrial lineages; two of them are geographically localized (Corfu Is. and Central Italy) and one encompasses a wide geographic area (Albania and Southern Italy). Most of the detected genetic variation (<81%) is apportioned among the aforementioned lineages.
Conclusions/Significance: Multiple analyses of mismatch distributions consistently supported both past demographic and spatial expansions with the former predating the latter; demographic expansions were consistently placed during interglacial warm phases of the Pleistocene while spatial expansions were restricted to cold periods. Coalescence methods revealed a scenario of past isolation with low levels of gene flow in line with what is already known for other co-distributed fairy shrimps and suggest drift as the prevailing force in promoting local divergence. We recommend that these evolutionary trajectories should be taken in proper consideration in any effort aimed at protecting Mediterranean temporary water bodies
A chemical survey of exoplanets with ARIEL
Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio
Late mortality and causes of death among 5-year survivors of childhood cancer diagnosed in the period 1960–1999 and registered in the Italian Off-Therapy Registry
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