BACTERIAL CELLULOSE REINFORCED THERMOPLASTIC COMPOSITES: PRELIMINARY EVALUATION OF FABRICATION AND PERFORMANCE

Mechanical properties of polyethylene (PE) composites were evaluated as a function of the addition of bacterial cellulose (BC). It was found that BC could improve the mechanical properties of the composites with or without the combination of traditional wood fiber. The improvements were affected by post-treatment. It was confirmed that BC had a significant influence on impact strength. The pellicle form of BC was able to achieve superior impact strength compared to the fluffy form of BC, but had similar effects on the tensile strength in comparison to the composites with fluffy BC

Regional Geological Survey of Hanggai, Xianxia and Chuancun, Zhejiang Province in China

This Open Access book introduces readers to the regional geology of Hanggai, Xianxia and Chuancun, the area between China's northern Zhejiang Province and southern Anhui Province and explores the strata, magmatic rocks and tectonic structures in 1:50,000 scale geological maps. Based on studies of multiple stratigraphic divisions, the standard stratigraphic section of the upper Ordovician Hirnantian in the lower Yangtze region is established, revealing for the first time numerous “Burgess Shale-type” sponge fossils in Hirnantian strata and identifying 10 grapholite fossil belts and various fossil categories, including chitin, trilobites, gastropods, brachiopods, and cephalopods. Moreover, the book identifies for the first time Late Ordovician volcanic events in northern Zhejiang province. The work represents a major contribution to research on Paleozoic strata in the Lower Yangtze region, and sheds new light on understanding the Hirnantian glacial event and biological extinction event in South China by providing a high-precision time scale. In addition, the book opens an important avenue for future research on sponge evolution after the Cambrian life explosion. As such, it offers a unique and valuable asset for researchers and graduate students alike

A Novel Spectral Clustering and its Application in Image Processing

This paper proposes an improved spectral clustering algorithm based on neighbour adaptive scale, who fully considers the local structure of dataset using neighbour adaptive scale, which simplifies the selection of parameters and makes the improved algorithm insensitive to both density and outliers. This paper illustrates the proposed algorithm not only has inhibition for certain outliers but is able to cluster the data sets with different scales. Experiments on UCI data sets show that the proposed method is effective. Some experiments were also performed in image clustering and image segmentation to demonstrate its excellent features in application

A Filter-Based and Parallel Unknown Tag Identification Protocol in Open RFID Systems

Unknown tag identification plays a pivotal role in radio frequency identification (RFID) systems, but it has not been fully investigated. This paper proposes a filter-based and parallel unknown tag identification protocol (FPUI) for open RFID systems. The FPUI adopts an RSQF-based fingerprint filter to reconcile the collision slots and discriminate the known tags from unknown tags. Meanwhile, it collects the IDs of unknown tags in parallel. FPUI achieves high performance through the following three steps: (1) adopting the RSQF-based filter to build an indicator vector, thus improving the space efficiency; (2) building a fingerprint filter to discriminate known tags from unknown tags, thus reducing the false positive rate; (3) employing a parallel identification scheme to collect the IDs of unknown tags, thus improving identification efficiency. The identification time of our protocol was minimized by conducting a theoretical analysis of the relevant parameters. Furthermore, the performance of our protocol was evaluated by conducting a wide range of simulation experiments. The theoretical analysis and simulation results indicated that our protocol significantly outperformed the current advanced protocols

History of coronary heart disease increased the mortality rate of patients with COVID-19: a nested case–control study

Objective Evaluate the risk of pre-existing comorbidities on COVID-19 mortality, and provide clinical suggestions accordingly.Setting A nested case–control design using confirmed case reports released from the news or the national/provincial/municipal health commissions of China between 18 December 2019 and 8 March 2020.Participants Patients with confirmed SARS-CoV-2 infection, excluding asymptomatic patients, in mainland China outside of Hubei Province.Outcome measures Patient demographics, survival time and status, and history of comorbidities.Method A total of 94 publicly reported deaths in locations outside of Hubei Province, mainland China, were included as cases. Each case was matched with up to three controls, based on gender and age ±1 year old (94 cases and 181 controls). The inverse probability-weighted Cox proportional hazard model was performed, controlling for age, gender and the early period of the outbreak.Results Of the 94 cases, the median age was 72.5 years old (IQR=16), and 59.6% were men, while in the control group the median age was 67 years old (IQR=22), and 64.6% were men. Adjusting for age, gender and the early period of the outbreak, poor health conditions were associated with a higher risk of COVID-19 mortality (HR of comorbidity score, 1.31 [95% CI 1.11 to 1.54]; p=0.001). The estimated mortality risk in patients with pre-existing coronary heart disease (CHD) was three times that of those without CHD (p<0.001). The estimated 30-day survival probability for a profile patient with pre-existing CHD (65-year-old woman with no other comorbidities) was 0.53 (95% CI 0.34 to 0.82), while it was 0.85 (95% CI 0.79 to 0.91) for those without CHD. Older age was also associated with increased mortality risk: every 1-year increase in age was associated with a 4% increased risk of mortality (p<0.001).Conclusion Extra care and early medical interventions are needed for patients with pre-existing comorbidities, especially CHD

A Filter-Based and Parallel Unknown Tag Identification Protocol in Open RFID Systems

Unknown tag identification plays a pivotal role in radio frequency identification (RFID) systems, but it has not been fully investigated. This paper proposes a filter-based and parallel unknown tag identification protocol (FPUI) for open RFID systems. The FPUI adopts an RSQF-based fingerprint filter to reconcile the collision slots and discriminate the known tags from unknown tags. Meanwhile, it collects the IDs of unknown tags in parallel. FPUI achieves high performance through the following three steps: (1) adopting the RSQF-based filter to build an indicator vector, thus improving the space efficiency; (2) building a fingerprint filter to discriminate known tags from unknown tags, thus reducing the false positive rate; (3) employing a parallel identification scheme to collect the IDs of unknown tags, thus improving identification efficiency. The identification time of our protocol was minimized by conducting a theoretical analysis of the relevant parameters. Furthermore, the performance of our protocol was evaluated by conducting a wide range of simulation experiments. The theoretical analysis and simulation results indicated that our protocol significantly outperformed the current advanced protocols

Perceived effectiveness of public health measures and positive attitudes during a pandemic: a large cross-sectional study in Shanghai, China

Objectives Building individuals’ positive attitudes during a pandemic is essential for facilitating psychological resilience. However, little is known about how public health measures may improve people’s positive attitudes during a pandemic. We investigated the potential mechanism underlying the association between individuals’ perceived effectiveness of public health measures and positive attitudes towards the success of pandemic control during the COVID-19 pandemic, by examining the parallel mediating effects of three types of threat appraisals: concerns about contracting the virus, perceived impact of the pandemic on life and estimated duration of the pandemic.Design, setting and participants In February 2020 when the COVID-19 infection was spreading rapidly in China, a large cross-sectional survey was conducted among 132 054 adults from the 16 districts in Shanghai, China.Outcome measures Perceived effectiveness of the public health measures, positive attitudes towards the success of pandemic control and threat appraisals.Results Results of structural equation modelling supported the hypothesised mediation model: perceived effectiveness of public health measures was associated with lower levels of concerns about contracting the virus (β=−0.20), perceived impact of the pandemic (β=−0.13) and perceived duration of the pandemic (β=−0.20), which were then associated with higher levels of positive attitudes towards the success of pandemic control (βs=−0.12 to −0.25).Conclusions The findings suggest that threat appraisals may be important pathways through which individuals’ evaluations of prevention strategies may influence their attitudes towards the success of pandemic control. The health authorities should consider reducing people’s inappropriate threat appraisals when designing public health policies to facilitate people’s positive attitudes during a pandemic