210 research outputs found
Visual speech encoding based on facial landmark registration
Visual Speech Recognition (VSR) related studies largely ignore the use of state of the art approaches in facial landmark localization, and are also deficit of robust visual features and its temporal encoding. In this work, we propose a visual speech temporal encoding by integrating state of the art fast and accurate facial landmark detection based on ensemble of regression trees learned using gradient boosting. The main contribution of this work is in proposing a fast and simple encoding of visual speech features derived from vertically symmetric point pairs (VeSPP) of facial landmarks corresponding to lip regions, and demonstrating their usefulness in temporal sequence comparisons using Dynamic Time Warping. VSR can be either speaker dependent (SD) or speaker independent (SI), and each of them poses different kind of challenges. In this work, we consider the SD scenario, and obtain 82.65% recognition accuracy on OuluVS database. Unlike recent research in VSR which makes use of auxiliary information such as audio, depth and color channels, our approach does not impose such constraints
From biometric scores to forensic likelihood ratios
In this chapter, we describe the issue of the interpretation of forensic evidence from scores computed by a biometric system. This is one of themost important topics into the so-called area of forensic biometrics.We will show the importance of the topic, introducing some of the key concepts of forensic science with respect to the interpretation of results prior to their presentation in court, which is increasingly addressed by the computation of likelihood ratios (LR). We will describe the LR methodology, and will illustrate it with an example of the evaluation of fingerprint evidence in forensic conditions, by means of a fingerprint biometric system.</p
Postoperative Symptoms, After-Care, and Return to Routine Activity After Laparoscopic Cholecystectomy
Wound-related symptoms were found to be common issues following laparoscopic cholecystectomy and may delay return to preoperative routine
Healthcare-associated fungal infections and emerging pathogens during the COVID-19 pandemic
Historically, fungi were mainly identified as plant and insect pathogens since they grow at 28°C. At the same time, bacteria are known to be the most common human pathogens as they are compatible with the host body temperature of 37°C. Because of immunocompromised hosts, cancer therapy, and malnutrition, fungi are rapidly gaining attention as human pathogens. Over 150 million people have severe fungal infections, which lead to approximately more than one million deaths per year. Moreover, diseases like cancer involving long-term therapy and prophylactic use of antifungal drugs in high-risk patients have increased the emergence of drug-resistant fungi, including highly virulent strains such as Candida auris. This clinical spectrum of fungal diseases ranges from superficial mucocutaneous lesions to more severe and life-threatening infections. This review article summarizes the effect of hospital environments, especially during the COVID-19 pandemic, on fungal infections and emerging pathogens. The review also provides insights into the various antifungal drugs and their existing challenges, thereby driving the need to search for novel antifungal agents
Comparison of the reverse bevel versus Franseen type endoscopic ultrasound needle
BACKGROUNDReverse bevel (RB) needle is widely used for endoscopic ultrasound fine needle biopsy (EUS-FNB). A 3-plane symmetrical needle with Franseen geometry (FG) has recently become available. AIMTo compare the clinical efficacy of FG to that of RB needle.METHODSA retrospective cohort study of all adult patients who underwent EUS-FNB for solid and mixed lesions either with 22G RB needle or 22G FG needle between January 2016 and February 2019 was undertaken. All cytology slides were reviewed by an independent gastrointestinal cytopathologist blinded to the needle used and the initial cytology report. The primary and secondary outcomes were to assess the sample adequacy using Euro-cytology criteria and the number of cell clusters, respectively.RESULTSTwo hundred and twenty six procedures were included in the study. RB needle was used in 128 procedures and FG needle in 98 procedures. The baseline characteristics of both groups were comparable. On multivariable analysis, FG needle (P = 0.02) and location of the lesion (P < 0.01) were independently associated with adequate tissue. Further, the use of FG needle (P = 0.04) and the size of the lesion (P = 0.02) were independently associated with acquisition of increased number of cell clusters.CONCLUSIONFG needle is superior to RB needle in acquiring adequate tissue and attaining higher number of cell clusters for solid and mixed lesions
The Simon and Simon-Mars Tensors for Stationary Einstein-Maxwell Fields
Modulo conventional scale factors, the Simon and Simon-Mars tensors are
defined for stationary vacuum spacetimes so that their equality follows from
the Bianchi identities of the second kind. In the nonvacuum case one can absorb
additional source terms into a redefinition of the Simon tensor so that this
equality is maintained. Among the electrovacuum class of solutions of the
Einstein-Maxwell equations, the expression for the Simon tensor in the
Kerr-Newman-Taub-NUT spacetime in terms of the Ernst potential is formally the
same as in the vacuum case (modulo a scale factor), and its vanishing
guarantees the simultaneous alignment of the principal null directions of the
Weyl tensor, the Papapetrou field associated with the timelike Killing vector
field, the electromagnetic field of the spacetime and even the Killing-Yano
tensor.Comment: 12 pages, Latex IOP article class, no figure
The Acquisition of Human B Cell Memory in Response to Plasmodium Falciparum Malaria
Immunity to Plasmodium falciparum (Pf), the most deadly agent of malaria, is only acquired after years of repeated infections and appears to wane rapidly without ongoing exposure. Antibodies (Abs) are central to malaria immunity, yet little is known about the Bâcell biology that underlies Pfâspecific humoral immunity. To address this gap in our knowledge we carried out a yearâlong prospective study of the acquisition and maintenance of longâlived plasma cells (LLPCs) and memory B cells (MBCs) in 225 individuals aged two to twentyâfive years in Mali, in an area of intense seasonal transmission. Using protein microarrays containing approximately 25% of the Pf proteome we determined that Pfâspecific Abs were acquired only gradually, in a stepwise fashion over years of Pf exposure. Pfâspecific Ab levels were significantly boosted each year during the transmission season but the majority of these Abs were short lived and were lost over the subsequent six month period of no transmission. Thus, we observed only a small incremental increase in stable Ab levels each year, presumably reflecting the slow acquisition LLPCs. The acquisition Pfâspecific MBCs mirrored the slow stepâwise acquisition of LLPCs. This slow acquisition of Pfâspecific LLPCs and MBCs was in sharp contrast to that of tetanus toxoid (TT)âspecific LLPCs and MBCs that were vi vi rapidly acquired and stably maintained following a single vaccination in individuals in this cohort. In addition to the development of normal MBCs we observed an expansion of atypical MBCs that are phenotypically similar to hyporesponsive FCRL4+ cells described in HIVâinfected individuals. Atypical MBC expansion correlated with cumulative exposure to Pf, and with persistent asymptomatic Pfâinfection in children, suggesting that the parasite may play a role in driving the expansion of atypical MBCs. Collectively, these observations provide a rare glimpse into the process of the acquisition of human B cell memory in response to infection and provide evidence for a selective deficit in the generation of Pfâspecific LLPCs and MBCs during malaria. Future studies will address the mechanisms underlying the slow acquisition of LLPCs and MBCs and the generation and function of atypical MBCs
Counter Turing Test CT^2: AI-Generated Text Detection is Not as Easy as You May Think -- Introducing AI Detectability Index
With the rise of prolific ChatGPT, the risk and consequences of AI-generated
text has increased alarmingly. To address the inevitable question of ownership
attribution for AI-generated artifacts, the US Copyright Office released a
statement stating that 'If a work's traditional elements of authorship were
produced by a machine, the work lacks human authorship and the Office will not
register it'. Furthermore, both the US and the EU governments have recently
drafted their initial proposals regarding the regulatory framework for AI.
Given this cynosural spotlight on generative AI, AI-generated text detection
(AGTD) has emerged as a topic that has already received immediate attention in
research, with some initial methods having been proposed, soon followed by
emergence of techniques to bypass detection. This paper introduces the Counter
Turing Test (CT^2), a benchmark consisting of techniques aiming to offer a
comprehensive evaluation of the robustness of existing AGTD techniques. Our
empirical findings unequivocally highlight the fragility of the proposed AGTD
methods under scrutiny. Amidst the extensive deliberations on policy-making for
regulating AI development, it is of utmost importance to assess the
detectability of content generated by LLMs. Thus, to establish a quantifiable
spectrum facilitating the evaluation and ranking of LLMs according to their
detectability levels, we propose the AI Detectability Index (ADI). We conduct a
thorough examination of 15 contemporary LLMs, empirically demonstrating that
larger LLMs tend to have a higher ADI, indicating they are less detectable
compared to smaller LLMs. We firmly believe that ADI holds significant value as
a tool for the wider NLP community, with the potential to serve as a rubric in
AI-related policy-making.Comment: EMNLP 2023 Mai
A bottom-up design framework for CAD tools to support design for additive manufacturing
Additive manufacturing (AM) technology is enabling a platform to produce parts with enhanced shape complexity. Design engineers are exploiting this capability to produce high performance functional parts. The current top-down approach to design for AM requires the designer to develop a design model in CAD software and then use optimization tools to adapt the design for the AM technology, however this approach neglects a number of desired criteria. This paper proposes an alternative bottom-up design framework for a new type of CAD tool which combines the knowledge required to design a part with evolutionary programming in order to design parts specifically for the AM platform.</p
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