A Reinforcement Learning Agent for Minutiae Extraction from Fingerprints

In this paper we show that reinforcement learning can be used for minutiae detection in fingerprint matching. Minutiae are characteristic features of fingerprints that determine their uniqueness. Classical approaches use a series of image processing steps for this task, but lack robustness because they are highly sensitive to noise and image quality. We propose a more robust approach, in which an autonomous agent walks around in the fingerprint and learns how to follow ridges in the fingerprint and how to recognize minutiae. The agent is situated in the environment, the fingerprint, and uses reinforcement learning to obtain an optimal policy. Multi-layer perceptrons are used for overcoming the difficulties of the large state space. By choosing the right reward structure and learning environment, the agent is able to learn the task. One of the main difficulties is that the goal states are not easily specified, for they are part of the learning task as well. That is, the recognition of minutiae has to be learned in addition to learning how to walk over the ridges in the fingerprint. Results of successful first experiments are presented

Government policy and wireless city networks: A comparative analysis of motivations, goals, services and their relation to network structure

Wireless City Networks are a recent, but growing phenomenon. In the United States hundreds of cities are looking into the possibility of rolling out Wi-Fi or WiMax based networks over substantial parts of the city. The underlying rationale is that wireless city networks are cheap and flexible alternatives for fixed broadband networks. Cities more and more see broadband Internet access as a necessary and therefore public utility to be provided to their communities at affordable prices or even free of charge. The deployment of wireless city networks is however more than just infrastructure provision. Initiatives are linked to broader city policies related to digital divide, city renewal, stimulation of innovation, stimulation of tourism, strengthening the economic fabric of the city, etc. In this article we will argue that explicit and implicit goals are directly linked to the coverage and topology of networks, the technology used, price and service modalities, etc. Furthermore we will argue that the differences in context between the US and Europe explain the different infrastructural trajectories taken. Overall and on the basis of empirical findings we caution for the overoptimistic view that Wi -Fi-based wireless city networks are an equal alternative for providing broadband access. There are both financial and technological uncertainties, which could have a serious impact on the performance of these initiatives

Government policy and wireless city networks : a comparative analysis of motivations, goals, services and their relation to network structure

Wireless City Networks are a recent, but growing phenomenon. In the United States hundreds of cities are looking into the possibility of rolling out Wi-Fi or WiMax based networks over substantial parts of the city. The underlying rationale is that wireless city networks are cheap and flexible alternatives for fixed broadband networks. Cities more and more see broadband Internet access as a necessary and therefore public utility to be provided to their communities at affordable prices or even free of charge. The deployment of wireless city networks is however more than just infrastructure provision. Initiatives are linked to broader city policies related to digital divide, city renewal, stimulation of innovation, stimulation of tourism, strengthening the economic fabric of the city, etc. In this article we will argue that explicit and implicit goals are directly linked to the coverage and topology of networks, the technology used, price and service modalities, etc. Furthermore we will argue that the differences in context between the US and Europe explain the different infrastructural trajectories taken. Overall and on the basis of empirical findings we caution for the overoptimistic view that Wi -Fi-based wireless city networks are an equal alternative for providing broadband access. There are both financial and technological uncertainties, which could have a serious impact on the performance of these initiatives

Oligometastatic Prostate Cancer:Results of a Dutch Multidisciplinary Consensus Meeting

Background: Oligometastatic prostate cancer (OMPC) is a heterogeneous disease state that is imperfectly understood, and its clinical implications are unclear. Objective: To determine the consensus of a Dutch multidisciplinary expert panel on biological aspects, treatment goals, and management of OMPC in daily clinical practice. Design, setting, and participants: The study comprised a modified Delphi method including an explorative survey with various statements and questions, followed by a consensus meeting to discuss and determine the agreement with revised statements and related items. The panel consisted of 34 Dutch representatives from urology, medical and radiation oncology, radiology, nuclear medicine, and basic research. Outcome measurements and statistical analysis: Agreement was determined with statements (five-point scale). Consensus was defined as ≥75% panel agreement with a statement. Results and limitations: Consensus existed for 56% of statements. The panel agreed that OMPC comprises a limited metastatic spread in the hormone-sensitive setting, in both the synchronous and the metachronous presentation. Limited metastatic spread was believed to involve three to five metastases and a maximum of two organs. Prostate-specific membrane antigen positron emission tomography/computed tomography scan was currently perceived as the most accurate diagnostic imaging modality. Although there was a consensus that targeted treatment of all metastases in OMPC will delay further dissemination of the disease, opinions on specific treatment regimens were divided. Panel outcomes were limited by the lack of scientific evidence on OMPC. Conclusions: A multidisciplinary panel reached a consensus that OMPC is a specific disease state requiring a tailored treatment approach. OMPC registries and clinical studies should focus on both the biology and the clinical parameters in relation to optimal treatment strategies in synchronous and metachronous OMPC. Patient summary: A group of Dutch medical specialists agreed that prostate cancer patients having few metastases may benefit from a new therapeutic approach. Clinical studies need to determine which treatment is best for each specific situation. A multidisciplinary panel reached consensus that oligometastatic prostate cancer (OMPC) is a specific disease state requiring a tailored treatment approach. OMPC registries and clinical studies should provide insight into the biology and clinical parameters in relation to optimal treatment strategies in synchronous and metachronous OMPC

The course of hepatitis E virus infection in pigs after contact-infection and intravenous inoculation

<p>Abstract</p> <p>Background</p> <p>Worldwide, hepatitis E virus (HEV) genotype 3 is observed in pigs and transmission to humans is implied. To be able to estimate public health risks from <it>e.g</it>. contact with pigs or consumption of pork products, the transmission routes and dynamics of infection should be identified. Hence, the course of HEV-infection in naturally infected pigs should be studied.</p> <p>Results</p> <p>To resemble natural transmission, 24 HEV-susceptible pigs were infected either by one-to-one exposure to intravenously inoculated pigs (C1-pigs; n = 10), by one-to-one exposure to contact-infected pigs (C2-pigs: n = 7; C3-pigs: n = 5) or due to an unknown non-intravenous infection route (one C2-pig and one C3-pig). The course of HEV-infection for contact-infected pigs was characterized by: faecal HEV RNA excretion that started at day 7 (95% confidence interval: 5–10) postexposure and lasted 23 (19–28) days; viremia that started after 13 (8–17) days of faecal HEV RNA excretion and lasted 11 (8–13) days; antibody development that was detected after 13 (10–16) days of faecal HEV RNA excretion. The time until onset of faecal HEV RNA excretion and onset of viremia was significantly shorter for <it>iv</it>-pigs compared to contact-infected pigs, whereas the duration of faecal HEV RNA excretion was significantly longer. At 28 days postinfection HEV RNA was detected less frequently in organs of contact-infected pigs compared to <it>iv</it>-pigs. For contact-infected pigs, HEV RNA was detected in 20 of 39 muscle samples that were proxies for pork at retail and in 4 of 7 urine samples.</p> <p>Conclusion</p> <p>The course of infection differed between infection routes, suggesting that contact-infection could be a better model for natural transmission than <it>iv </it>inoculation. Urine and meat were identified as possible HEV-sources for pig-to-pig and pig-to-human HEV transmission.</p

Farm biosecurity measures to prevent hepatitis E virus infection in finishing pigs on endemically infected pig farms

Hepatitis E virus (HEV) can be transmitted from pigs to humans and cause liver inflammation. Pigs are a major reservoir of HEV and most slaughter pigs show evidence of infection by presence of antibodies (ELISA) or viral RNA (PCR). Reducing the number of HEV infected pigs at slaughter would likely reduce human exposure, yet how this can be achieved, is unknown. We aimed to identify and quantify the effect of biosecurity measures to deliver HEV negative batches of pigs to slaughter. A case-control study was performed with Dutch pig farms selected based on results of multiple slaughter batches. Case farms delivered at least one PCR and ELISA negative batch to slaughter (PCR−ELISA−), indicating absence of HEV infection, and control farms had the highest proportion of PCR and/or ELISA positive batches (PCR+ELISA+), indicating high within-farm transmission. Data about biosecurity and housing were collected via a questionnaire and an audit. Variables were selected by regularization (LASSO regression) and ranked, based the frequency of variable selection. The odds ratios (OR) for the relation between case-control status and the highest ranked variables were determined via grouped logistic regression. Thirty-five case farms, with 10 to 60% PCR−ELISA− batches, and 38 control farms with on average 40% PCR+ELISA+ batches, were included. Rubber and steel floor material in fattening pens had the highest ranking and increased the odds of a PCR−ELISA− batch by 5.87 (95%CI 3.03–11.6) and 7.13 (95%CI 3.05–16.9) respectively. Cleaning pig driving boards weekly (OR 1.99 (95%CI 1.07–3.80)), and fly control with predatory flies (OR 4.52 (95%CI 1.59–13.5)) were protective, whereas a long fattening period was a risk. This study shows that cleaning and cleanability of floors and fomites and adequate fly control are measures to consider for HEV control in infected farms. Yet, intervention studies are needed to confirm the robustness of these outcomes

Experimental and field investigations of exposure, replication and transmission of SARS-CoV-2 in pigs in the Netherlands

In order to assess the risk of SARS-CoV-2 infection, transmission and reservoir development in swine, we combined results of an experimental and two observational studies. First, intranasal and intratracheal challenge of eight pigs did not result in infection, based on clinical signs and PCR on swab and lung tissue samples. Two serum samples returned a low positive result in virus neutralization, in line with findings in other infection experiments in pigs. Next, a retrospective observational study was performed in the Netherlands in the spring of 2020. Serum samples (N =417) obtained at slaughter from 17 farms located in a region with a high human case incidence in the first wave of the pandemic. Samples were tested with protein micro array, plaque reduction neutralization test and receptor-binding-domain ELISA. None of the serum samples was positive in all three assays, although six samples from one farm returned a low positive result in PRNT (titers 40-80). Therefore we conclude that serological evidence for large scale transmission was not observed. Finally, an outbreak of respiratory disease in pigs on one farm, coinciding with recent exposure to SARS-CoV-2 infected animal caretakers, was investigated. Tonsil swabs and paired serum samples were tested. No evidence for infection with SARS-CoV-2 was found. In conclusion, Although in both the experimental and the observational study few samples returned low antibody titer results in PRNT infection with SARS-CoV-2 was not confirmed. It was concluded that sporadic infections in the field cannot be excluded, but large-scale SARS-CoV-2 transmission among pigs is unlikely.info:eu-repo/semantics/publishedVersio

Use of gallium-68 prostate-specific membrane antigen positron-emission tomography for detecting lymph node metastases in primary and recurrent prostate cancer and location of recurrence after radical prostatectomy: an overview of the current literature

Objectives: To review the literature to determine the sensitivity and specificity of gallium-68 prostate-specific membrane antigen (68Ga-PSMA) positron-emission tomography (PET) for detecting pelvic lymph node metastases in patients with primary prostate cancer (PCa), and the positive predictive value in patients with biochemical recurrence (BCR) after initial curative treatment, and, in addition, to determine the detection rate and management impact of 68Ga-PSMA PET in patients with BCR after radical prostatectomy (RP). Materials and Methods: We performed a comprehensive literature search. Search terms used in MEDLINE, EMBASE and Science Direct were ‘(PSMA, 68Ga-PSMA, 68Gallium-PSMA, Ga-68-PSMA or prostate-specific membrane antigen)’ and ‘(histology, lymph node, staging, sensitivity, specificity, positive predictive value, recurrence, recurrent or detection)’. Relevant abstracts were reviewed and full-text articles obtained where possible. References to and from obtained articles were searched to identify further relevant articles. Results: Nine retrospective and two prospective studies described the sensitivity and specificity of 68Ga-PSMA PET for detecting pelvic lymph node metastases before initial treatment, which ranged from 33.3% to 100% and 80% to 100%, respectively. In eight retrospective studies, the positive predictive value of 68Ga-P

Big Data in een Smart City: Verhalen uit een seminarreeks van het PMB Leerhuis

Elk jaar organiseert het Leerhuis van het Projectmanagementbureau samen met de Hogeschool van Amsterdam een thematische seminarreeks. De koppeling van de wetenschappelijke theorie met de dagelijkse praktijk biedt een waardevolle verdieping van de kennis van de medewerkers van het Projectmanagementbureau. Centraal staat de toepasbaarheid in ons werk aan complexe en multidisciplinaire opgaven in Amsterdam. In 2018/2019 hebben we gekozen voor het smart city-concept, waarbij big data en tools roepen om toepassingsmogelijkheden in de aanpak van stedelijke problematiek. Wie in de media de discussie over de opkomst van smart cities volgt, krijgt vaak het beeld voorgeschoteld van een grote controlekamer, vol met monitors en schermen. Daarop worden allerhande processen in de stad op de minuut gevolgd: de doorstroming van het verkeer op de hoofdwegen, de weersverwachting en waterstanden, meldingen aan politie en brandweer of samenscholingen van menigtes in de openbare ruimte. Naast deze ‘control room’-visie staan twee minder bekende benaderingen: ‘Smart Citizens’ zet technologie in om burgers meer zeggenschap te geven, terwijl de ‘Creative City’ de stad beziet als ‘living lab’. Alle drie de verschijningsvormen van de smart city bieden kansen om de kwaliteit van leven in de stad te verbeteren, én roepen tegelijkertijd vragen op over hun doelmatigheid en legitimiteit. De verschillende bijdragen aan de seminarreeks over smart cities gingen dieper in op de mogelijkheden en valkuilen van de drie smart city perspectieven. Deze zijn gebundeld in dit magazine en aangevuld met een aantal lessen en handvatten voor de medewerkers van het PMB