20 research outputs found

    Indexing Audio-Visual Sequences by Joint Audio and Video Processing

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    The focus of this work is oriented to the creation of a content-based hierarchical organisation of audio-visual data (a description scheme) and to the creation of meta-data (descriptors) to associate with audio and/or visual signals. The generation of efficient indices to access audio-visual databases is strictly connected to the generation of content descriptors and to the hierarchical representation of audio-visual material. Once a hierarchy can be extracted from the data analysis, a nested indexing structure can be created to access relevant information at a specific level of detail. Accordingly, a query can be made very specific in relationship to the level of detail that is required by the user. In order to construct the hierarchy, we describe how to extract information content from audio-visual sequences so as to have different hierarchical indicators (or descriptors), which can be associated to each media (audio, video). At this stage, video and audio signals can be separated into temporally consistent elements. At the lowest level, information is organised in frames (groups of pixels for visual information, groups of consecutive samples for audio information). At a higher level, low-level consistent temporal entities are identified: in case of digital image sequences, these consist of shots (or continuous camera records) which can be obtained by detecting cuts or special effects such as dissolves, fade in and fade out; in case of audio information, these represent consistent audio segments belonging to one specific audio type (such as speech, music, silence, ...). One more level up, patterns of video shots or audio segments can be recognised so as to reflect more meaningful structures such as dialogues, actions, ... At the highest level, information is organised so as to establish correlation beyond the temporal organisation of information, allowing to reflect classes of visual or audio types: we call these classes idioms. The paper ends with a description of possible solutions to allow a cross-modal analysis of audio and video information, which may validate or invalidate the proposed hierarchy, and in some cases enable more sophisticated levels of representation of information content

    Scene Break Detection: A Comparison

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    The automatic organization of video databases according to the semantic content of data is a key aspect for efficient indexing and fast retrieval of audio-visual material. In order to generate indices that can be used to access a video database, a description of each video sequence is necessary. The identification of objects present in a frame and the track of their motion and interaction in space and time, is attractive but not yet very robust. For this reason, since the early 90's, attempts have been applied in trying to segment a video in shots. For each shot a representative frame of the shot, called k-frame, is usually chosen and the video can be analysed through its k-frames. Even if abrupt scene changes are relatively easy to be detected, it is more difficult to identify special effects, such as dissolve, that were operated in the editing stage to merge two shots. Unfortunately, these special effects are normally used to stress the importance of the scene change (from a content point of view), so they are extremely relevant therefore they should not be missed. Beside, it is very important to determine precisely the beginning and the end of the transition in the case of dissolves and fades. In this work, two new parameters are proposed. These characterize the precision of boundaries of special effects when the scene change involves more than two frames. They are combined with the common recall and precision parameters. Three for cut detection are considered: histogram-based, motion-based and contour-based. These algorithms are tested and compared on several video sequences. Results will show that the best performance is achieved by the global histogram-based method which uses color information

    Measuring Care and Justice Moral Orientation: Italian validation and revision of the MMO-2 scale

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    This study presents the Italian adaptation of the Measure of Moral Orientation Second Revision (MMO-2). Based on Carol Gilligan’s theory of the Ethics of Care, the MMO-2 was designed to measure two complementary moral stances, namely Care and Justice. For this study, questionnaire responses from 683 university students were assessed against an Italian-adapted MMO-2 scale. Data were analysed through Exploratory Structural Equation Modelling first as separate scenarios and then as a single model. The final model comprises four intercorrelated pairs of latent variables and shows highly satisfactory goodness of fit indices with moderate construct validity and reliability. Strengths, limitations, and directions for the future developments of the MMO-2 will be discussed

    COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

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    Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≀ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

    SARS-CoV-2 serology after COVID-19 in multiple sclerosis: An international cohort study

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    DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

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    We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

    Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

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    IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

    How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

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    COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Audio as a Support to Scene Change Detection and Characterization of Video Sequences

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    A challenging problem to construct video databases is the organization of video information. The development of algorithms able to organize video information according to semantic content of the data is getting more and more important. This will allow algorithms such as indexing and retrieval to work more efficiently. Until now, an attempt to extract semantic information has been performed using only video information. As a video sequence is constructed from a 2-D projection of a 3-D scene, video processing has shown its limitations especially in solving problems such as object identification or object tracking, reducing the ability to extract semantic characteristics. A possibility to overcome the problem is to use additional information. The associated audio signal is then the most natural way to obtain this information. This paper presents a technique which combines video and audio information together for classification and indexing purposes. The classification is performed on the audio signal; a general framework that uses the results of such classification is then proposed for organizing video information
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