Detecting stealthy cyberattacks on adaptive cruise control vehicles: A machine learning approach

With the advent of vehicles equipped with advanced driver-assistance systems, such as adaptive cruise control (ACC) and other automated driving features, the potential for cyberattacks on these automated vehicles (AVs) has emerged. While overt attacks that force vehicles to collide may be easily identified, more insidious attacks, which only slightly alter driving behavior, can result in network-wide increases in congestion, fuel consumption, and even crash risk without being easily detected. To address the detection of such attacks, we first present a traffic model framework for three types of potential cyberattacks: malicious manipulation of vehicle control commands, false data injection attacks on sensor measurements, and denial-of-service (DoS) attacks. We then investigate the impacts of these attacks at both the individual vehicle (micro) and traffic flow (macro) levels. A novel generative adversarial network (GAN)-based anomaly detection model is proposed for real-time identification of such attacks using vehicle trajectory data. We provide numerical evidence {to demonstrate} the efficacy of our machine learning approach in detecting cyberattacks on ACC-equipped vehicles. The proposed method is compared against some recently proposed neural network models and observed to have higher accuracy in identifying anomalous driving behaviors of ACC vehicles

Evaluation of Adaptive Signal Control Technology - Volume 3: Comparison of TBC 2017 and ASCT 2017

Data were collected at five intersections along the Neil Street corridor in Champaign, Illinois, before deployment of SynchroGreen, an adaptive signal control technology (ASCT). The volume, delay, and queue length data from the field for TBC (time based coordination) 2017 conditions were compared to the data from ASCT (adaptive signal control technology) 2017 conditions, at the 97% confidence level. The field volumes were compared for 57 lane groups (approaches). Traffic volume on 7% of the lane groups significantly increased, on 72% remained unchanged, and on only 21% significantly decreased. Stopped delays increased in 56% of the cases, remained unchanged in 40%, and decreased in 4%. Queue length increased in 35% of the cases and remained unchanged in 65%. To determine ASCT performance, the changes in volume, delay, and queue length combined were considered. An overall performance indicator (PI) was determined for each approach of each intersection at each time period. The performance indicators were Imp (Improved), Unch (Unchanged), and Det (Deteriorated), with 91% confidence. One lane group was excluded from further analysis due to insufficient volume; of the 56 lane groups analyzed, 5% showed improvement, 32% remained unchanged, and 63% (35 cases) showed deterioration. Out of 35 cases, deterioration in 20 cases could be explained by contributing factors such as frequency of unfavorable arrival types under ASCT 2017, as compared to TBC 2017; a few cases of volume increase under ASCT 2017; ASCT miscount of traffic volumes; signal timing changes under ASCT 2017; and increased proportion of vehicles stopped under ASCT 2017. However, in the 15 remaining cases, there was no reasonable explanation for the PI deteriorations when ASCT was operatingIDOT-R27-127Ope

First realization of macroscopic Fourier ptychography for hundred-meter distance sub-diffraction imaging

Fourier ptychography (FP) imaging, drawing on the idea of synthetic aperture, has been demonstrated as a potential approach for remote sub-diffraction-limited imaging. Nevertheless, the farthest imaging distance is still limited around 10 m even though there has been a significant improvement in macroscopic FP. The most severely issue in increasing the imaging distance is FoV limitation caused by far-field condition for diffraction. Here, we propose to modify the Fourier far-field condition for rough reflective objects, aiming to overcome the small FoV limitation by using a divergent beam to illuminate objects. A joint optimization of pupil function and target image is utilized to attain the aberration-free image while estimating the pupil function simultaneously. Benefiting from the optimized reconstruction algorithm which effectively expands the camera's effective aperture, we experimentally implement several FP systems suited for imaging distance of 12 m, 90 m, and 170 m with the maximum synthetic aperture of 200 mm. The maximum imaging distance and synthetic aperture are thus improved by more than one order of magnitude of the state-of-the-art works with a fourfold improvement in the resolution. Our findings demonstrate significant potential for advancing the field of macroscopic FP, propelling it into a new stage of development

Electrostatic spraying of membrane electrode for proton exchange membrane fuel cell

Abstract(#br)In order to improve the performance of proton exchange membrane fuel cell (PEMFC), the optimization of electrostatic spraying of membrane electrode was conducted. The influence of the spraying voltage on morphology, elemental composition of catalyst layer, and performance of the PEMFC were investigated. The results show that increasing spraying voltage could reduce agglomeration of the carbon-supported platinum particles, leading to more uniform pore distribution. High voltage did not accelerate oxidation of platinum catalyst. A high electrochemical active surface area of 26.18 m 2 /g pt was obtained when the platinum-carbon catalyst layer was deposited in cone jet mode. With further increasing spraying voltage, the total ohmic resistance and catalytic activity were changed slightly, whereas the charge transfer resistance was increased. Using the optimized electrostatic spraying parameters (injection rate = 100 μL min −1 , spraying voltage = 8.5 kV, and working distance = 12 mm), a peak power density of 1.408 W cm −2 was obtained with an output voltage of 0.451 V

Effects of short-term travel on COVID-19 spread: A novel SEIR model and case study in Minnesota.

The novel coronavirus responsible for COVID-19 was first identified in Hubei Province, China in December, 2019. Within a matter of months the virus had spread and become a global pandemic. In addition to international air travel, local travel (e.g. by passenger car) contributes to the geographic spread of COVID-19. We modify the common susceptible-exposed-infectious-removed (SEIR) virus spread model and investigate the extent to which short-term travel associated with driving influences the spread of the virus. We consider the case study of the US state of Minnesota, and calibrated the proposed model with travel and viral spread data. Using our modified SEIR model that considers local short-term travel, we are able to better explain the virus spread than using the long-term travel SEIR model. Short-term travel associated with driving is predicted to be a significant contributor to the historical and future spread of COVID-19. The calibrated model also predicts the proportion of infections that were detected. We find that if driving trips remain at current levels, a substantial increase in COVID-19 cases may be observed in Minnesota, while decreasing intrastate travel could help contain the virus spread

Bacteroides salyersiae is a potent chondroitin sulfate-degrading species in the human gut microbiota

Abstract Chondroitin sulfate (CS) has widely been used as a symptomatic slow-acting drug or a dietary supplement for the treatment and prevention of osteoarthritis. However, CS could not be absorbed after oral intake due to its polyanionic nature and large molecular weight. Gut microbiota has recently been proposed to play a pivotal role in the metabolism of drugs and nutrients. Nonetheless, how CS is degraded by the human gut microbiota has not been fully characterized. In the present study, we demonstrated that each human gut microbiota was characterized with a unique capability for CS degradation. Degradation and fermentation of CS by the human gut microbiota produced significant amounts of unsaturated CS oligosaccharides (CSOSs) and short-chain fatty acids. To uncover which microbes were responsible for CS degradation, we isolated a total of 586 bacterial strains with a potential CS-degrading capability from 23 human fecal samples. Bacteroides salyersiae was a potent species for CS degradation in the human gut microbiota and produced the highest amount of CSOSs as compared to other well-recognized CS-degraders, including Bacteroides finegoldii, Bacteroides thetaiotaomicron, Bacteroides xylanisolvens, and Bacteroides ovatus. Genomic analysis suggested that B. salyersiae was armed with multiple carbohydrate-active enzymes that could potentially degrade CS into CSOSs. By using a spent medium assay, we further demonstrated that the unsaturated tetrasaccharide (udp4) produced by the primary degrader B. salyersiae could serve as a “public goods” molecule for the growth of Bacteroides stercoris, a secondary CS-degrader that was proficient at fermenting CSOSs but not CS. Taken together, our study provides insights into the metabolism of CS by the human gut microbiota, which has promising implications for the development of medical and nutritional therapies for osteoarthritis. Video Abstrac

Tunable quantum coherence of organic luminescent radical qubits centered in star-like block copolymers and self-assembling nanostructures

Electronic or nuclear spins such as inorganic ‘nitrogen-vacancy’ centers in diamond and other defects in silicon represent a promising type of quantum bits (qubits) for applications in quantum information processing, data storage as well as quantum sensing. However, it remains challenging to achieve scalable and spatially defined organization of a large number of spins as qubits. Therefore, development of new materials and technologies to regulate spin-spin distance and interaction plays an important role in preservation of quantum coherence and realization of coherent exchange of information between spin qubits. Herein, we report that spatially defined organization of organic radicals as electronic spins can be realized via a strategy of block copolymer self-assembly. We demonstrate quantum coherence and spin-lattice relaxation of organic luminescent radical spins can be facilely tuned using a library of well-defined star-like block copolymers containing a common core of tris[4-(p-benzyl)-2,6-dichlorophenyl]methyl radical in the center, from which diblock polyesters are grafted via controllable ring-opening polymerization. The fine tuning of the incompatibility and the volume ratio of the two blocks of polyesters leads to not only a series of self-assembling patterns (i.e., spheres, cylinders, lamellae, and gyroids) with phase-separation of the spins in the nanometer scale, but also tunable spin-lattice relaxation dynamics and spin coherence lifetimes that strongly depend on the lengths and rigidities of the polymeric matrices surrounding the organic radicals as molecular spins. Such strategy of block copolymer self-assembly may offer a generally applicable approach to integrating and organizing molecular spins as promising qubits into scalable architectures and functional devices towards cutting-edge applications in quantum information processing, quantum computation and spintronics

Air travel data during the COVID-19 pandemic in the United States

The flight data contains flights within the Northeastern US and contains flight date, duration, origin, destination, airline, and aircraft registration. The aircraft registration information has been cross referenced with the Federal Aviation Administration (FAA) database to identify the aircraft type and seating configuration on that aircraft. The dataset also contains normalized COVID-19 infection levels for each county in the five-state region of New York, Massachusetts, Connecticut, Rhode Island, and New Jersey. This data is presented as the proportion of infected people in each county on a day-by-day basis.This dataset contains flight data for all commercial flights in the Northeastern US during the COVID-19 pandemic, as well as code to calibrate and simulate an SEIR model that incorporates the flight data into the transmission process

Polysaccharide from Edible Alga Enteromorpha clathrata Improves Ulcerative Colitis in Association with Increased Abundance of Parabacteroides spp. in the Gut Microbiota of Dextran Sulfate Sodium-Fed Mice

Polysaccharide from the edible alga Enteromorpha clathrata has been demonstrated to exert beneficial effects on human health. However, what effect it has on inflammatory bowel diseases has not been investigated. Here, using a mouse model of dextran sulfate sodium (DSS)-induced ulcerative colitis, we illustrate that Enteromorpha clathrata polysaccharide (ECP) could alleviate body weight loss, reduce incidences of colonic bleeding, improve stool consistency and ameliorate mucosal damage in diseased mice. 16S rRNA high-throughput sequencing and bioinformatic analysis indicated that ECP significantly changed the structure of the gut microbiota and increased the abundance of Parabacteroides spp. in DSS-fed mice. In vitro fermentation studies further confirmed that ECP could promote the growth of Parabacteroides distasonis F1-28, a next-generation probiotic bacterium isolated from the human gut, and increase its production of short-chain fatty acids. Additionally, Parabacteroides distasonis F1-28 was also found to have anti-ulcerative colitis effects in DSS-fed mice. Altogether, our study demonstrates for the first time a beneficial effect of ECP on ulcerative colitis and provides a possible basis for understanding its therapeutic mechanisms from the perspective of symbiotic gut bacteria Parabacteroides distasonis

Additional file 1 of Bacteroides salyersiae is a potent chondroitin sulfate-degrading species in the human gut microbiota

Additional file 1: Figure S1. TLC showing the degradation of CS by the human gut microbiota. The degradation was monitored at 12 hours (A), 24 hours (B), 36 hours (C), 48 hours (D), and 72 hours (E). Figure S2. Degradation of CS by the human gut microbiota. Relative CS content in the culture medium at 72 hours (A). UPLC-MS/MS analysis of CSOSs in the culture medium of donor T25 (B). Total ion chromatograms showing the elution profiles of CSOSs in the culture medium of donor T25 at different time points (C). Figure S3. Mass spectrum showing the signals of udp2 (A), udp4 (B), and udp6 (C) according to their m/z ratios. The CSOSs, including udp2, udp4, and udp6 were produced in the culture medium as a result of CS degradation by the human gut microbiota. Figure S4. Changes in the structure of the human gut microbiota before and after fermentation. Venn diagram showing the differences of the operational taxonomic units (OTUs) (A). Observed species (B). Chao1 index (C). Shannon index (D). Heatmap of the abundance of gut bacteria at the genus level (E). Figure S5. Differences in the composition of the human gut microbiota before and after fermentation. Wilcoxon rank-sum test analysis of the gut microbiota at the species level (A). Linear discriminant analysis (LDA) Effect Size (LEfSe) analysis of the gut microbiota at the species level (B). Only bacterial taxa with an LDA score of above 3.0 were listed. Figure S6. Isolation of CS-degrading bacteria from the human gut microbiota. Different species of bacteria were obtained from different human fecal samples (A-W). Figure S7. B. salyersiae CSP6 was identified as a potent bacterium for CS-degradation in the present study. Heatmap of the relative abundance of the consumed CS (A). Phylogenetic tree analysis of the CS-degrading bacteria based on the 16S rRNA gene (B). Figure S8. TLC showing the degradation of CS by different human fecal isolates. The results were presented from B. thetaiotaomicron E1-7 to H. porci E13-26 (A-I). Figure S9. TLC showing the degradation of CS by different human fecal isolates. The results were presented from E. durans E13-16 to S. oneidensis P30-2-30 (A-H). Figure S10. Degradation and fermentation of CS by B. finegoldii B36-12, B. thetaiotaomicron E1-7, B. xylanisolvens B33-17, and B. ovatus B33-4. Concentrations of different SCFAs in the culture medium of B. finegoldii B36-12 (A), B. thetaiotaomicron E1-7 (B), B. xylanisolvens B33-17 (C), and B. ovatus B33-4 (D). * p < 0.05; ** p < 0.01. Figure S11. CS degradation by B. finegoldii B36-12, B. thetaiotaomicron E1-7, B. xylanisolvens B33-17, and B. ovatus B33-4. UPLC-MS/MS analysis of CSOSs produced by B. finegoldii B36-12 (A), B. thetaiotaomicron E1-7 (B), B. xylanisolvens B33-17 (C), and B. ovatus B33-4 (D). Total ion chromatograms showing the elution profiles of CSOSs in the culture medium of B. finegoldii B36-12 (E), B. thetaiotaomicron E1-7 (F), B. xylanisolvens B33-17 (G), and B. ovatus B33-4 (H) at different time points. * p < 0.05. Figure S12. Mass spectrum showing the signals of udp4 (A), udp6 (B), and udp8 (C) according to their m/z ratios. The CSOSs, including udp4, udp6, and udp8 were produced in the culture medium as a result of CS degradation by B. salyersiae CSP6, B. finegoldii B36-12, B. xylanisolvens B33-17, B. thetaiotaomicron E1-7, and B. ovatus B33-4. Figure S13. Degradation of CS by different strains of B. salyersiae. TLC showing the degradation of CS by B. salyersiae CSP6 and B. salyersiae FL17 (A). Relative carbohydrate content in the culture medium at different time points (B). B. salyersiae FL17 was previously isolated from the fecal sample of a healthy individual. This individual has not participated in the present study. Figure S14. Genome analysis of B. salyersiae CSP6. COG function classification (A). KEGG pathway analysis (B). Figure S15. Screening of candidate bacteria that could utilize udp4 using the spent medium assay. TLC showing the utilization of udp4 by different human gut bacteria. (A). List of the tested bacteria (B). Figure S16. Cross-feeding interactions between B. salyersiae and B. stercoris identified using the spent medium assay. Relative carbohydrate content in the culture medium (A). Growth curve (B) and CFU analysis (C). Concentrations of total SCFAs (D), acetate (E), and propionate (F) in the culture medium of B. salyersiae and B. stercoris. * p < 0.05; ** p < 0.01; *** p < 0.001. Figure S17. Mass spectrum showing the signal of udp4 according to the m/z ratio. The udp4 concentration in the spent medium was analyzed using UPLC-MS/MS. Table S1. Summary of CS-degrading bacteria isolated from the human fecal samples. Table S2. Summary of the potential enzymes for CS degradation in B. salyersiae CSP6 based on the genomic analysis. Supplementary Table S3. Genome annotation of B. salyersiae CSP6. Supplementary Table S4. CAZyme annotation of B. salyersiae CSP6