Towards Vision-Based Smart Hospitals: A System for Tracking and Monitoring Hand Hygiene Compliance

One in twenty-five patients admitted to a hospital will suffer from a hospital acquired infection. If we can intelligently track healthcare staff, patients, and visitors, we can better understand the sources of such infections. We envision a smart hospital capable of increasing operational efficiency and improving patient care with less spending. In this paper, we propose a non-intrusive vision-based system for tracking people's activity in hospitals. We evaluate our method for the problem of measuring hand hygiene compliance. Empirically, our method outperforms existing solutions such as proximity-based techniques and covert in-person observational studies. We present intuitive, qualitative results that analyze human movement patterns and conduct spatial analytics which convey our method's interpretability. This work is a step towards a computer-vision based smart hospital and demonstrates promising results for reducing hospital acquired infections.Comment: Machine Learning for Healthcare Conference (MLHC

Differentially Private Video Activity Recognition

In recent years, differential privacy has seen significant advancements in image classification; however, its application to video activity recognition remains under-explored. This paper addresses the challenges of applying differential privacy to video activity recognition, which primarily stem from: (1) a discrepancy between the desired privacy level for entire videos and the nature of input data processed by contemporary video architectures, which are typically short, segmented clips; and (2) the complexity and sheer size of video datasets relative to those in image classification, which render traditional differential privacy methods inadequate. To tackle these issues, we propose Multi-Clip DP-SGD, a novel framework for enforcing video-level differential privacy through clip-based classification models. This method samples multiple clips from each video, averages their gradients, and applies gradient clipping in DP-SGD without incurring additional privacy loss. Moreover, we incorporate a parameter-efficient transfer learning strategy to make the model scalable for large-scale video datasets. Through extensive evaluations on the UCF-101 and HMDB-51 datasets, our approach exhibits impressive performance, achieving 81% accuracy with a privacy budget of epsilon=5 on UCF-101, marking a 76% improvement compared to a direct application of DP-SGD. Furthermore, we demonstrate that our transfer learning strategy is versatile and can enhance differentially private image classification across an array of datasets including CheXpert, ImageNet, CIFAR-10, and CIFAR-100

A Wideband and Ultra-Thin Metamaterial Absorber Based on Resistive FSS

A wideband, ultra-thin, wide-angle and polarization-insensitive metamaterial absorber with a single-layer resistive frequency selective surface (FSS) is proposed. The simulated results show that the absorption rate of the absorber is greater than 90% in a frequency range of 24.1–42.6 GHz, and the relative absorption bandwidth is up to 55.47%. The thickness of the structure is 1.2 mm, which is 0.088 λ and 0.156 λ for the lowest and highest frequencies, respectively. The power loss density is analyzed to explore the mechanism of the absorption and the resistive film layer is important for the wideband absorption. Meanwhile, a strong absorption for oblique incidence with wide angle and the characteristics of polarization insensitivity are achieved for the proposed design

Experimental Study of Pile-Soil Interaction of Integral Abutment Bridges with Low-Cyclic Lateral Load

This paper experimentally investigates the mechanism and deformation of circular and rectangular reinforced concrete (RC) piles of integral abutment bridges (IAB). Pseudo-static tests of the RC piles under low-cyclic loading were conducted to simulate the periodic displacement of the IAB due to temperature changes. A lateral displacement load was applied on the pile head and the characteristics of energy dissipation, strain, bending moment, lateral displacement, and pile damage were analyzed. The results show that the ratio of reinforcement and the shape of the section significantly influence the energy dissipation and RC pile ductility. The ratio of reinforcement (1.6% to 3.2%) is suitable for the RC pile, providing excellent energy dissipation and ductility. The lateral resistance of the RC pile accounts for over 50% of the whole soil-pile system in the elastic stage. However, the resistance distribution of the surrounding soil of the pile is more than 50% in the latter stages. Furthermore, the performance of the circular RC pile was better than the rectangular one. It is recommended to use the circular pile in bridge design when the RC pile is used as the foundation of IABs, especially in areas with high seismic fortification levels

Construction of a Dengue NanoLuc Reporter Virus for In Vivo Live Imaging in Mice

Since the first isolation in 1943, the dengue virus (DENV) has spread throughout the world, but effective antiviral drugs or vaccines are still not available. To provide a more stable reporter DENV for vaccine development and antiviral drug screening, we constructed a reporter DENV containing the NanoLuc reporter gene, which was inserted into the 5′ untranslated region and capsid junction region, enabling rapid virus rescue by in vitro ligation. In addition, we established a live imaging mouse model and found that the reporter virus maintained the neurovirulence of prototype DENV before engineering. DENV-4 exhibited dramatically increased neurovirulence following a glycosylation site-defective mutation in the envelope protein. Significant mice mortality with neurological onset symptoms was observed after intracranial infection of wild-type (WT) mice, thus providing a visualization tool for DENV virulence assessment. Using this model, DENV was detected in the intestinal tissues of WT mice after infection, suggesting that intestinal lymphoid tissues play an essential role in DENV pathogenesis

Synthesis of sandwich-structured silver@polydopamine@silver shells with enhanced antibacterial activities

| openaire: EC/H2020/796280/EU//CADOACCFAPThe unique antibacterial characteristics of Ag nanomaterials offer a wide potential range of applications, but achieving rapid and durable antibacterial efficacy is challenging. This is because the speed and durability of the antibacterial function make conflicting demands on the structural design: the former requires the direct exposure of Ag to the surrounding environment, whereas the durability requires Ag to be protected from the environment. To overcome this incompatibility, we synthesize sandwich-structured polydopamine shells decorated both internally and externally with Ag nanoparticles, which exhibit prompt and lasting bioactivity in applications. These shells are biocompatible and can be used in vivo to counter bacterial infection caused by methicillin-resistant Staphylococcus aureus superbugs and to inhibit biofilm formation. This work represents a new paradigm for the design of composite materials with enhanced antibacterial properties.Peer reviewe

Autoclaving‐Derived Surface Coating with In Vitro and In Vivo Antimicrobial and Antibiofilm Efficacies

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136399/1/adhm201601173.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136399/2/adhm201601173-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136399/3/adhm201601173_am.pd

Comparison of Different Isolation Methods for Plasma-Derived Extracellular Vesicles in Patients with Hyperlipidemia

Extracellular vesicles are commonly found in human body fluids and can reflect current physiological conditions of human body and act as biomarkers of disease. The quality of isolated extracellular vesicles facilitates the early diagnosis of various diseases accompanied by hyperlipidemia. Nonetheless, there are no reports on which special methods are suitable for isolating extracellular vesicles from the plasma of patients with hyperlipidemia. Thus, this study compared three different research-based extracellular vesicle isolation approaches, namely ultracentrifugation (UC), polyethylene glycol (PEG) precipitation, and size exclusion chromatography (SEC), and determined which of them was the most effective method. We selected blood samples from 12 patients with clinically diagnosed hyperlipidemia and isolated plasma-derived extracellular vesicles using three methods. The morphology of the isolated extracellular vesicles was observed using transmission electron microscopy, while the concentration was detected by asymmetric flow field-flow fractionation and multi-angle light scattering. Marker proteins were identified by Western blotting, and protein composition was evaluated by silver staining. Both determined the contaminations in the extracellular vesicle samples. The results showed that the three methods can be successfully used for the isolation of extracellular vesicles. The extracellular vesicles isolated by UC were larger in size, and the yield was much lower. Although the yield of extracellular vesicles isolated by PEG precipitation was greatly improved, the contamination was increased. Of the three methods, only the SEC-isolated extracellular vesicles were characterized by high yield and low contamination. Therefore, our data suggested that the SEC was a more ideal method for isolating extracellular vesicles from the plasma of patients with hyperlipidemia