Throughput capacity of two-hop relay MANETs under finite buffers

Since the seminal work of Grossglauser and Tse [1], the two-hop relay algorithm and its variants have been attractive for mobile ad hoc networks (MANETs) due to their simplicity and efficiency. However, most literature assumed an infinite buffer size for each node, which is obviously not applicable to a realistic MANET. In this paper, we focus on the exact throughput capacity study of two-hop relay MANETs under the practical finite relay buffer scenario. The arrival process and departure process of the relay queue are fully characterized, and an ergodic Markov chain-based framework is also provided. With this framework, we obtain the limiting distribution of the relay queue and derive the throughput capacity under any relay buffer size. Extensive simulation results are provided to validate our theoretical framework and explore the relationship among the throughput capacity, the relay buffer size and the number of nodes

MOTOR EVOKED POTENTIALS AND TRANSCUTANEOUS MAGNETO-ELECTRICAL NERVE STIMULATION

The purpose of this study was to identify the mechanism of cerebral cortex human isometric contraction information processing. By using transcutaneous magneto-electrical nerve stimulation technique, musculi flexor crapi radialis/ulnaris isometric contracts, the nerve digitals palmares/volares communes nerve mediani/ulnaris were stimulated. The results showed that many evoked potential amplitude of gyrus postcentralis and praecentralis, lobules parietals superior and inferior, gyrus temporaries’ superior/medius/inferior are significantly different to each other. Some peak absolute latency and interpeak /interwave latency, either sensory or motor was shorter in the same side hemisphere, while those in the opposing side hemisphere were longer. The above results indicated that the sensory afferent information occurred previously in the same side hemisphere rather than the opposing hemisphere

A Hierarchical Spatio-Temporal Graph Convolutional Neural Network for Anomaly Detection in Videos

Deep learning models have been widely used for anomaly detection in surveillance videos. Typical models are equipped with the capability to reconstruct normal videos and evaluate the reconstruction errors on anomalous videos to indicate the extent of abnormalities. However, existing approaches suffer from two disadvantages. Firstly, they can only encode the movements of each identity independently, without considering the interactions among identities which may also indicate anomalies. Secondly, they leverage inflexible models whose structures are fixed under different scenes, this configuration disables the understanding of scenes. In this paper, we propose a Hierarchical Spatio-Temporal Graph Convolutional Neural Network (HSTGCNN) to address these problems, the HSTGCNN is composed of multiple branches that correspond to different levels of graph representations. High-level graph representations encode the trajectories of people and the interactions among multiple identities while low-level graph representations encode the local body postures of each person. Furthermore, we propose to weightedly combine multiple branches that are better at different scenes. An improvement over single-level graph representations is achieved in this way. An understanding of scenes is achieved and serves anomaly detection. High-level graph representations are assigned higher weights to encode moving speed and directions of people in low-resolution videos while low-level graph representations are assigned higher weights to encode human skeletons in high-resolution videos. Experimental results show that the proposed HSTGCNN significantly outperforms current state-of-the-art models on four benchmark datasets (UCSD Pedestrian, ShanghaiTech, CUHK Avenue and IITB-Corridor) by using much less learnable parameters.Comment: Accepted to IEEE Transactions on Circuits and Systems for Video Technology (T-CSVT

Experimental Exploration of Influence of Recycled Polymer Components on Rutting Resistance and Fatigue Behavior of Asphalt Mixtures

Rutting and fatigue of asphalt pavements, as two important distresses, are significantly influenced by the properties of binders. This study aimed to improve the resistance of asphalt mixtures to permanent deformation and fatigue using two recycled waste-polymer components in recycled crumb rubber (CR) and polyethylene (PE). The assessed pavement properties of the modified asphalt mixtures were characterized by wheel tracking, uniaxial penetration, and four-point bending (4PB) tests. The wheel tracking test indicated that the integrated modification technique, by functionally incorporating PE and CR, enhanced the dynamic stability of the asphalt mixtures and that PE dosage was a key variable. From the uniaxial penetration test, it was revealed that the shear strength of the asphalt mixtures at high temperature could be improved by the integrated modification method, indicating the method’s potential to reduce the flow rutting of asphalt pavements. Meanwhile, both the CR and PE were shown to increase the cohesive behavior of the asphalt mixtures, with the friction angle value sensitive to PE dosage. The addition of PE reduced the fatigue life of the asphalt mixtures; the CR improved the PE-modified mixtures’ fatigue resistance. The findings from this study will be beneficial in developing sustainable and durable asphalt pavements, tailoring the reuse of different types of polymer wastes in asphalt pavements, and minimizing waste disposal at landfills

Incision pressing, a simple and effective intervention to reduce colorectal surgical site infection: A propensity score-matched study

BackgroundColorectal surgery is associated with a high risk of surgical site infection (SSI). In March 2017, we developed an intervention, called “PRESS”, with the aim of reducing colorectal superficial SSI. This study assessed the effect of the new intervention in reducing the rates of superficial SSI in colorectal surgery.MethodsThis study was a retrospective review of 312 PRESS+ patients compared to 171 historical control PRESS− patients who were 18 years of age or older and underwent elective colorectal surgery with clean-contaminated wounds from January 2015 to June 2020. In the PRESS+ groups, we pressed the incision downward hard with clean gauze after the interrupted suturing of the skin. Propensity score matching with 15 variables was performed in a 1:1 ratio to reduce selection bias. Univariate analysis and multivariate analysis were performed to identify risk factors associated with SSI.ResultsThe characteristics of the PRESS+ (n = 160) and PRESS− (n = 160) groups were well balanced after propensity score matching. The PRESS+ group had a lower superficial SSI rate (1.9% vs. 6.9%, P = 0.029) and a lower overall SSI rate (2.5% vs. 10.0%, P = 0.006) than the PRESS− group. Furthermore, multivariate analysis showed that the incisional press was an effective protective factor for superficial SSI (adjusted odds ratio = 0.215, 95% confidence interval = 0.057–0.818, P = 0.024). In addition, female sex (P = 0.048) and blood transfusion (P = 0.011) were demonstrated to be independent risk factors for superficial SSI.ConclusionThe incisional press after suturing is a simple, costless, and effective intervention in reducing superficial incisional SSI

Novel synthetic bisindolylmaleimide alkaloids inhibit STAT3 activation by binding to the SH2 domain and suppress breast xenograft tumor growth

Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in malignant tumors and plays important roles in multiple aspects of cancer aggressiveness. Thus, targeting STAT3 promises to be an attractive strategy for the treatment of advanced metastatic tumors. Bisindolylmaleimide alkaloid (BMA) has been shown to have anti-cancer activities and was thought to suppress tumor cell growth by inhibiting protein kinase C. In this study, we show that a newly synthesized BMA analog, BMA097, is effective in suppressing tumor cell and xenograft growth and in inducing spontaneous apoptosis. We also provide evidence that BMA097 binds directly to the SH2 domain of STAT3 and inhibits STAT3 phosphorylation and activation, leading to reduced expression of STAT3 downstream target genes. Structure activity relationship analysis revealed that the hydroxymethyl group in the 2,5-dihydropyrrole-2,5-dione prohibits STAT3 inhibitory activity of BMA analogs. Altogether, we conclude that the synthetic BMA analogs may be developed as anti-cancer drugs by targeting and binding to the SH2 domain of STAT3 and inhibiting the STAT3 signaling pathway

111In-Labeled Cystine-Knot Peptides Based on the Agouti-Related Protein for Targeting Tumor Angiogenesis

Agouti-related protein (AgRP) is a 4-kDa cystine-knot peptide of human origin with four disulfide bonds and four solvent-exposed loops. The cell adhesion receptor integrin αvβ3 is an important tumor angiogenesis factor that determines the invasiveness and metastatic ability of many malignant tumors. AgRP mutants have been engineered to bind to integrin αvβ3 with high affinity and specificity using directed evolution. Here, AgRP mutants 7C and 6E were radiolabeled with 111In and evaluated for in vivo targeting of tumor integrin αvβ3 receptors. AgRP peptides were conjugated to the metal chelator 1, 4, 7, 10-tetra-azacyclododecane- N, N′, N″, N‴-tetraacetic acid (DOTA) and radiolabeled with 111In. The stability of the radiopeptides 111In-DOTA-AgRP-7C and 111In-DOTA-AgRP-6E was tested in phosphate-buffered saline (PBS) and mouse serum, respectively. Cell uptake assays of the radiolabeled peptides were performed in U87MG cell lines. Biodistribution studies were performed to evaluate the in vivo performance of the two resulting probes using mice bearing integrin-expressing U87MG xenograft tumors. Both AgRP peptides were easily labeled with 111In in high yield and radiochemical purity (>99%). The two probes exhibited high stability in phosphate-buffered saline and mouse serum. Compared with 111In-DOTA-AgRP-6E, 111In-DOTA-AgRP-7C showed increased U87MG tumor uptake and longer tumor retention (5.74 ± 1.60 and 1.29 ± 0.02%ID/g at 0.5 and 24 h, resp.), which was consistent with measurements of cell uptake. Moreover, the tumor uptake of 111In-DOTA-AgRP-7C was specifically inhibited by coinjection with an excess of the integrin-binding peptidomimetic c(RGDyK). Thus, 111In-DOTA-AgRP-7C is a promising probe for targeting integrin αvβ3 positive tumors in living subjects