Nonparametric estimation of the fragmentation kernel based on a PDE stationary distribution approximation

We consider a stochastic individual-based model in continuous time to describe a size-structured population for cell divisions. This model is motivated by the detection of cellular aging in biology. We address here the problem of nonparametric estimation of the kernel ruling the divisions based on the eigenvalue problem related to the asymptotic behavior in large population. This inverse problem involves a multiplicative deconvolution operator. Using Fourier technics we derive a nonparametric estimator whose consistency is studied. The main difficulty comes from the non-standard equations connecting the Fourier transforms of the kernel and the parameters of the model. A numerical study is carried out and we pay special attention to the derivation of bandwidths by using resampling

Tradeoff Analysis of Delay-Power-CSIT Quality of Dynamic BackPressure Algorithm for Energy Efficient OFDM Systems

In this paper, we analyze the fundamental power-delay tradeoff in point-to-point OFDM systems under imperfect channel state information quality and non-ideal circuit power. We consider the dynamic back- pressure (DBP) algorithm, where the transmitter determines the rate and power control actions based on the instantaneous channel state information (CSIT) and the queue state information (QSI). We exploit a general fluid queue dynamics using a continuous time dynamic equation. Using the sample-path approach and renewal theory, we decompose the average delay in terms of multiple unfinished works along a sample path, and derive an upper bound on the average delay under the DBP power control, which is asymptotically accurate at small delay regime. We show that despite imperfect CSIT quality and non-ideal circuit power, the average power (P) of the DBP policy scales with delay (D) as P = O(Dexp(1/D)) at small delay regime. While the impacts of CSIT quality and circuit power appears as the coefficients of the scaling law, they may be significant in some operating regimes.Comment: 30 page

Status and Problems of Adverse Event Reporting Systems in Korean Hospitals

Objectives: This study identifies the current status and problems of adverse event reporting system in Korean hospitals. Thedata obtained from this study will be used to raise international awareness and enable collaborative researches on patientsafety. Methods: We distributed the questionnaire developed by the Agency for Healthcare Research and Quality (AHRQ),USA to the 265 risk managers of hospitals by e-mail. Seventy-two percent of the risk managers responded to the inquiry.Results: Eighty-five percent of the hospitals responded that they collect information regarding the event where harm hasoccurred or might have occurred to a patient. Seventy-five percent of the hospitals did not allow individuals to report occurrenceswithout identifying themselves. Only 54% of the hospitals had an organized patient safety program that manages orcoordinates all of the hospitals patient safety activities. The most frequent reason why errors were not reported was the fearof individuals being involved in the investigation and potential disadvantage resulting from it. Eighty-five percent of the hospitalsproduced reports of their adverse event data, but 68% of the hospitals did not distribute occurrence reports within thehospital. Conclusions: Lack of standardized reporting system, available information, procedures for protecting the reportingindividuals, and mindlessness/indifference of the hospital employees are identified as the major problems. Therefore, it iscrucial to address these problems to develop appropriate solutions, enable proactive involvement from the healthcare community,and change the overall patient safety culture, specifically protecting privacy, to increase the quality of service in thehealthcare industry.OAIID:oai:osos.snu.ac.kr:snu2010-01/102/0000028528/2SEQ:2PERF_CD:SNU2010-01EVAL_ITEM_CD:102USER_ID:0000028528ADJUST_YN:YEMP_ID:A076124DEPT_CD:811FILENAME:34 Status and Problems of Adverse Event Reporting Systems in Korean Hospitals.pdfDEPT_NM:간호학과EMAIL:[email protected]_YN:NCONFIRM:

Defeating Opaque Predicates Statically through Machine Learning and Binary Analysis

International audienceWe present a new approach that bridges binary analysis techniques with machine learning classification for the purpose of providing a static and generic evaluation technique for opaque predicates, regardless of their constructions. We use this technique as a static automated deobfuscation tool to remove the opaque predicates introduced by obfuscation mechanisms. According to our experimental results, our models have up to 98% accuracy at detecting and deob-fuscating state-of-the-art opaque predicates patterns. By contrast, the leading edge deobfuscation methods based on symbolic execution show less accuracy mostly due to the SMT solvers constraints and the lack of scalability of dynamic symbolic analyses. Our approach underlines the efficiency of hybrid symbolic analysis and machine learning techniques for a static and generic deobfuscation methodology

On the Localization of Ultrasound Image Slices within Point Distribution Models

Thyroid disorders are most commonly diagnosed using high-resolution Ultrasound (US). Longitudinal nodule tracking is a pivotal diagnostic protocol for monitoring changes in pathological thyroid morphology. This task, however, imposes a substantial cognitive load on clinicians due to the inherent challenge of maintaining a mental 3D reconstruction of the organ. We thus present a framework for automated US image slice localization within a 3D shape representation to ease how such sonographic diagnoses are carried out. Our proposed method learns a common latent embedding space between US image patches and the 3D surface of an individual's thyroid shape, or a statistical aggregation in the form of a statistical shape model (SSM), via contrastive metric learning. Using cross-modality registration and Procrustes analysis, we leverage features from our model to register US slices to a 3D mesh representation of the thyroid shape. We demonstrate that our multi-modal registration framework can localize images on the 3D surface topology of a patient-specific organ and the mean shape of an SSM. Experimental results indicate slice positions can be predicted within an average of 1.2 mm of the ground-truth slice location on the patient-specific 3D anatomy and 4.6 mm on the SSM, exemplifying its usefulness for slice localization during sonographic acquisitions. Code is publically available: \href{https://github.com/vuenc/slice-to-shape}{https://github.com/vuenc/slice-to-shape}Comment: ShapeMI Workshop @ MICCAI 2023; 12 pages 2 figure

Ultrasound characteristics of foot and ankle structures in healthy, coper, and chronically unstable ankles

Objective: Ankle sprains constitute approximately 85% of all ankle injuries and up to 70% of people experience residual symptoms. Whilst the injury to ligaments is well understood the potential role of other foot and ankle structures has not been explored. The objective was to characterise and compare selected ankle structures in participants with and without a history of lateral ankle sprain. Methods: 71 participants were divided into 31 healthy, 20 coper, and 20 chronic ankle instability groups. Ultrasound images of the anterior talofibular and calcaneofibular ligaments, fibularis tendons and muscles, tibialis posterior and Achilles tendon were obtained. Thickness, length, and cross sectional areas were measured and compared between groups. Results: When under tension the anterior talofibular ligament was longer in copers and chronic ankle instability groups compared to healthy participants (p < 0.001 and p = 0.001 respectively). The chronic ankle instability group had the thickest ATFL and CFL among the three groups (p < 0.001). No significant differences (p > 0.05) in tendons and muscles were observed between the three groups. Conclusions: The ultrasound protocol proved reliable and was used to evaluate the length, thickness, and CSA of selected ankle structures. The length of the ATFL and the thickness of the ATFL and CFL were longer and thicker in injured groups compared to healthy

S3M: Scalable Statistical Shape Modeling through Unsupervised Correspondences

Statistical shape models (SSMs) are an established way to represent the anatomy of a population with various clinically relevant applications. However, they typically require domain expertise, and labor-intensive landmark annotations to construct. We address these shortcomings by proposing an unsupervised method that leverages deep geometric features and functional correspondences to simultaneously learn local and global shape structures across population anatomies. Our pipeline significantly improves unsupervised correspondence estimation for SSMs compared to baseline methods, even on highly irregular surface topologies. We demonstrate this for two different anatomical structures: the thyroid and a multi-chamber heart dataset. Furthermore, our method is robust enough to learn from noisy neural network predictions, potentially enabling scaling SSMs to larger patient populations without manual segmentation annotation.Comment: Accepted at MICCAI 2023. 13 pages, 6 figure

Quantitative transcript analysis of the inducible expression system pSIP: comparison of the overexpression of Lactobacillus spp. β-galactosidases in Lactobacillus plantarum

<p>Abstract</p> <p>Background</p> <p>Two sets of overlapping genes, <it>lacLMReu </it>and <it>lacLMAci</it>, encoding heterodimeric β-galactosidases from <it>Lactobacillus reuteri </it>and <it>Lactobacillus acidophilus</it>, respectively, have previously been cloned and expressed using the pSIP vector system and <it>Lactobacillus plantarum </it>WCSF1 as host. Despite the high similarity between these <it>lacLM </it>genes and the use of identical cloning and expression strategies, strains harboring <it>lacLMReu </it>produced about twenty-fold more β-galactosidase than strains containing <it>lacLMAci</it>.</p> <p>Results</p> <p>In this study, the plasmid copy numbers (PCN) of expression vectors pEH9R (<it>lacLMReu</it>) and pEH9A (<it>lacLMAci</it>) as well as the transcription levels of both <it>lacLM </it>genes were compared using quantitative PCR methods. Analyses of parallel fermentations of <it>L. plantarum </it>harboring either pEH9R or pEH9A showed that the expression plasmids were present in similar copy numbers. However, transcript levels of <it>lacLM </it>from <it>L. reuteri </it>(pEH9R) were up to 18 times higher than those of <it>lacLM </it>from <it>L. acidophilus </it>(pEH9A). As a control, it was shown that the expression levels of regulatory genes involved in pheromone-induced promoter activation were similar in both strains.</p> <p>Conclusion</p> <p>The use of identical expression strategies for highly similar genes led to very different mRNA levels. The data indicate that this difference is primarily caused by translational effects that are likely to affect both mRNA synthesis rates and mRNA stability. These translational effects thus seem to be a dominant determinant for the success of gene expression efforts in lactobacilli.</p