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2022 ◽  
Vol 16 (4) ◽  
pp. 1-22
Siddharth Bhatia ◽  
Rui Liu ◽  
Bryan Hooi ◽  
Minji Yoon ◽  
Kijung Shin ◽  

Given a stream of graph edges from a dynamic graph, how can we assign anomaly scores to edges in an online manner, for the purpose of detecting unusual behavior, using constant time and memory? Existing approaches aim to detect individually surprising edges. In this work, we propose Midas , which focuses on detecting microcluster anomalies , or suddenly arriving groups of suspiciously similar edges, such as lockstep behavior, including denial of service attacks in network traffic data. We further propose Midas -F, to solve the problem by which anomalies are incorporated into the algorithm’s internal states, creating a “poisoning” effect that can allow future anomalies to slip through undetected. Midas -F introduces two modifications: (1) we modify the anomaly scoring function, aiming to reduce the “poisoning” effect of newly arriving edges; (2) we introduce a conditional merge step, which updates the algorithm’s data structures after each time tick, but only if the anomaly score is below a threshold value, also to reduce the “poisoning” effect. Experiments show that Midas -F has significantly higher accuracy than Midas . In general, the algorithms proposed in this work have the following properties: (a) they detects microcluster anomalies while providing theoretical guarantees about the false positive probability; (b) they are online, thus processing each edge in constant time and constant memory, and also processes the data orders-of-magnitude faster than state-of-the-art approaches; and (c) they provides up to 62% higher area under the receiver operating characteristic curve than state-of-the-art approaches.

2022 ◽  
Ting-Kai Leung ◽  
Chia-Wei Li ◽  
Yu-Chun Lo ◽  
Ping-Yen Tsai ◽  
Jia-Yi Wang

Abstract There is still no clear explanation of the process of perceptual consciousness that connects our body with brain. Innovation on the technology of bioceramic has now advanced towards clinical applications, including rehabilitation of brain infarction, therapies of insomnia and migraine. To demonstrate how ‘resonant energy transfer through the bioceramic material with tempo sound and visible light spectrum’ (bioceramic material stimulation, BMS) non-invasively affects perceptual consciousness, we investigated the responses of participants to BMS on perceptual consciousness by questionnaire of subjective descriptions and analyzed resting state fMRI during BMS. There were 61.3% participants who were categorized as positive group with various types of perceptual consciousness. By setting a threshold value at ‘p<0.001’, enhanced connections of ‘parahippocampal gyrus to cerebellar lobule V’ and ‘angular gyrus to precuneus’ were found. However, decreased connection of ‘caudate nucleus to cerebellar lobule VIIb’ was found. We conclude that the most affected brain functions by BMS including somatosensory, audio-visual perception and social cognition. The analysis of functional connectivity during BMS may help us gain more knowledge of consciousness and related division of neuroscience in humans.

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0257498
Kaiyang Zhong

In recent years, digital finance has become a crucial part of the financial system and reshaped the mode of green finance in China. Digital finance has brought certain impact on economic growth, industrial structure, and resident income, which may affect pollution. The nexus of digital finance and environment in China is thus worth exploring. By revising the traditional Environmental Kuznets Curve model with income inequality variable, this paper decomposes the environmental effects of economic activities into income growth effect, industrial structure effect and income inequality effect, and use panel data of China’s provinces to conduct an empirical analysis. The results reveal the following: (1) the Environmental Kuznets Curve is still valid in sample, and digital finance can reduce air and water pollution (as measured through SO2 and COD emission) directly; (2) in the influence mechanism, digital finance can alleviate income inequality and promote green industrial structure, thus reducing pollution indirectly, but the scale effect of income growth outweighs the technological effect, which increases pollution indirectly; and (3) digital finance has a threshold effect on improving the environment, then an acceleration effect appears after a certain threshold value. From the regional perspective, digital finance development in eastern regions is generally ahead of central and western regions, and the effects of environmental improvement in the eastern regions are greater. According to the study, this paper suggest that digital finance can be an effective way to promote social sustainability by alleviating income inequality and environmental sustainability by reducing pollution.

Ritch T. J. Geitenbeek ◽  
Enrico Martin ◽  
Laura H. Graven ◽  
Martijn P. G. Broen ◽  
Monique H. M. E. Anten ◽  

Abstract Purpose Detecting malignant peripheral nerve sheath tumors (MPNSTs) remains difficult. 18F-FDG PET-CT has been shown helpful, but ideal threshold values of semi-quantitative markers remain unclear, partially because of variation among scanners. Using EU-certified scanners diagnostic accuracy of ideal and commonly used 18F-FDG PET-CT thresholds were investigated and differences between adult and pediatric lesions were evaluated. Methods A retrospective cohort study was performed including patients from two hospitals with a clinical or radiological suspicion of MPNST between 2013 and 2019. Several markers were studied for ideal threshold values and differences among adults and children. A diagnostic algorithm was subsequently developed. Results Sixty patients were included (10 MPNSTs). Ideal threshold values were 5.8 for SUVmax (sensitivity 0.70, specificity 0.92), 5.0 for SUVpeak (sensitivity 0.70, specificity 0.97), 1.7 for TLmax (sensitivity 0.90, specificity 0.86), and 2.3 for TLmean (sensitivity 0.90, specificity 0.79). The standard TLmean threshold value of 2.0 yielded a sensitivity of 0.90 and specificity of 0.74, while the standard SUVmax threshold value of 3.5 yielded a sensitivity of 0.80 and specificity of 0.63. SUVmax and adjusted SUV for lean body mass (SUL) were lower in children, but tumor-to-liver ratios were similar in adult and pediatric lesions. Using TLmean > 2.0 or TLmean < 2.0 and SUVmax > 3.5, a sensitivity and specificity of 1.00 and 0.63 can be achieved. Conclusion 18F-FDG PET-CT offers adequate accuracy to detect MPNSTs. SUV values in pediatric MPNSTs may be lower, but tumor-to-liver ratios are not. By combining TLmean and SUVmax values, a 100% sensitivity can be achieved with acceptable specificity.

2022 ◽  
Vol 12 (2) ◽  
pp. 689
Gamaliel Gonzales ◽  
Felix Costan ◽  
Decem Suladay ◽  
Roselyn Gonzales ◽  
Lynne Enriquez ◽  

Technological transitions in the education sector of developing economies are faced with a range of barriers, involving resource scarcity, socio-cultural concerns, and issues related to management and policy. The popularity of Industry 4.0 has prompted Education 4.0 (EDUC4), an approach to learning that involves transformation using advanced technologies. While a recent work reported a comprehensive list of barriers to EDUC4 implementation, particularly in developing economies, further analysis to identify those priority barriers remains a gap. Thus, this work addresses this gap by introducing a novel methodological extension of the decision-making trial and evaluation laboratory (DEMATEL) method following the integration of Fermatean fuzzy sets (FFS). The FFS, compared to other fuzzy environments, could capture higher levels of uncertainties that are associated when eliciting judgments necessary for the DEMATEL. Such integration is aided by the maximum mean de-entropy (MMDE) algorithm, which analytically determines the threshold value crucial for constructing the prominence-relation map of the DEMATEL. Following its application in evaluating the implementation of EDUC4 in Philippine universities, the critical barriers are the lack of training resources, costs, insufficiency of available technologies, skills gap of human resources, knowledge gap, and the complexity of the learning platforms. Among this set, barriers related to cost and lack of training resources are deemed the most prominent ones. The statistical test on the impact of addressing the two prominent barriers shows that addressing the barrier related to costs yields statistically more favorable results regarding the mitigation of other EDUC4 implementation barriers. Although these insights may contain idiosyncrasies, they can serve as starting points of discussion in other relevant developing economies. These methodological and practical contributions advance the development of analytical tools under uncertainty that can handle pressing problems such as the EDUC4 implementation.

2022 ◽  
Vol 44 (1) ◽  
pp. 329-335
Panagiotis Halvatsiotis ◽  
Sofia Vassiliu ◽  
Panagiotis Koulouvaris ◽  
Kalliopi Chatzantonaki ◽  
Konstantinos Asonitis ◽  

The aim of this study is to investigate the circulating variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from Athens and from rural areas in Greece during July and August 2021. We also present a rapid review of literature regarding significant SARS-CoV-2 mutations and their impact on public health. A total of 2500 nasopharyngeal swab specimens were collected from suspected COVID-19 cases (definition by WHO 2021b). Viral nucleic acid extraction was implemented using an automatic extractor and the RNA recovered underwent qRT-PCR in order to characterize the specimens as positive or negative for SARS-CoV-2. The positive specimens were then used to identify specific Spike gene mutations and characterize the emerging SARS-CoV-2 variants. For this step, various kits were utilized. From the 2500 clinical specimens, 220 were tested positive for SARS-CoV-2 indicating a prevalence of 8.8% among suspected cases. The RT-PCR Ct (Cycle threshold) Value ranged from 19 to 25 which corresponds to medium to high copy numbers of the virus in the positive samples. From the 220 positive specimens 148 (67.3%) were from Athens and 72 (32.7%) from Greek rural areas. As far as the Spike mutations investigated: N501Y appeared in all the samples, D614G mutation appeared in 212 (96.4%) samples with a prevalence of 87.2% in Athens and 98.6% in the countryside, E484K had a prevalence of 10.8% and 12.5% in Athens and the rural areas, respectively. K417N was found in 18 (12.2%) samples from Athens and four (5.6%) from the countryside, P681H was present in 51 (34.5%) Athenian specimens and 14 (19.4%) specimens from rural areas, HV69-70 was carried in 32.4% and 19.4% of the samples from Athens and the countryside, respectively. P681R had a prevalence of 87.2% in Athens and 98.6% in rural areas, and none of the specimens carried the L452R mutation. 62 (28.2%) samples carried the N501Y, P681H, D614G and HV69-70 mutations simultaneously and the corresponding variant was characterized as the Alpha (UK) variant (B 1.1.7). Only six (2.7%) samples from the center of Athens had the N501Y, E484K, K417N and D614G mutations simultaneously and the virus responsible was characterized as the Beta (South African) variant (B 1.351). Our study explored the SARS-CoV-2 variants using RT-PCR in a representative cohort of samples collected from Greece in July and August 2021. The prevalent mutations identified were N501Y (100%), D614G (96.4%), P681R (90.1%) and the variants identified were the Delta (90.1%), Alpha (28.2%) and Beta (2.7%).

Yu-Lin Gong ◽  
Ming-Jia Hu ◽  
Hui-Fang Yang ◽  
Bo Han

Abstract ReliefF algorithm was used to analyze the weight of each water quality evaluation factor, and then based on the Relevance Vector Machine (RVM), Particle Swarm Optimization (PSO) was used to optimize the kernel width factor and hyperparameters of RVM to build a water quality evaluation model, and the experimental results of RVM, PSO-RVM, ReliefF-RVM and PSO-ReliefF-RVM were compared. The results show that ReliefF algorithm, combined with threshold value, selects 5 evaluation factors with significant weight from 8 evaluation factors, which reduces the amount of data used in the model, CSI index is used to calculate the separability of each evaluation factor combination. The results show that the overall separability of the combination is best when the evaluation factor with significant weight is reserved. When different water quality evaluation factors were included, the evaluation accuracy of PSO-ReliefF-RVM model reached 95.74%, 14.23% higher than that of RVM model, which verified the effectiveness of PSO algorithm and ReliefF algorithm, and had a higher guiding significance for the study of water quality grade evaluation. It has good practical application value.

2022 ◽  
Vol 5 ◽  
pp. 151
Gabriela Cormick ◽  
Natalia Matamoros ◽  
Iris B. Romero ◽  
Surya M. Perez ◽  
Cintia White ◽  

Background: Food fortification is an effective strategy that has been recommended for improving population calcium inadequate intakes. Increasing calcium concentration of water has been proposed as a possible strategy to improve calcium intake. The objective of this study was to determine the sensory threshold of different calcium salts added to drinking water using survival analysis. Methods: We performed the triangle test methodology for samples of water with added calcium using three different calcium salts: calcium chloride, calcium gluconate and calcium lactate. For each salt, a panel of 54 consumers tested seven batches of three water samples. Data were adjusted for chance and sensory threshold was estimated using the survival methodology and a discrimination of 50%. Results: The threshold value estimation for calcium gluconate was 587 ± 131 mg/L of water, corresponding to 25% discrimination, for calcium lactate was 676 ± 186 mg/L, corresponding to 50% discrimination, and for calcium chloride was 291 ± 73 mg/L, corresponding to 50% discrimination. Conclusions: These results show that water with calcium added in different salts and up to a concentration of 500 mg of calcium/L of water is feasible. The calcium salt allowing the highest calcium concentration with the lowest perceived changes in taste was calcium gluconate. Future studies need to explore stability and acceptability over longer periods of time.

Mohamed Saied Abdelgawad ◽  
Mohamed Hamdy Kayed ◽  
Mohamed Ihab Samy Reda ◽  
Eman Abdelzaher ◽  
Ahmed Hafez Farhoud ◽  

Abstract Background Non-neoplastic brain lesions can be misdiagnosed as low-grade gliomas. Conventional magnetic resonance (MR) imaging may be non-specific. Additional imaging modalities such as spectroscopy (MRS), perfusion and diffusion imaging aid in diagnosis of such lesions. However, contradictory and overlapping results are still present. Hence, our purpose was to evaluate the role of advanced neuro-imaging in differentiation between low-grade gliomas (WHO grade II) and MR morphologically similar non-neoplastic lesions and to prove which modality has the most accurate results in differentiation. Results All patients were classified into two main groups: patients with low-grade glioma (n = 12; mean age, 38.8 ± 16; 8 males) and patients with non-neoplastic lesions (n = 27; mean age, 36.6 ± 15; 19 males) based on the histopathological and clinical–radiological diagnosis. Using ROC curve analysis, a threshold value of 0.93 for rCBV (AUC = 0.875, PPV = 92%, NPV = 71.4%) and a threshold value of 2.5 for Cho/NAA (AUC = 0.829, PPV = 92%, NPV = 71.4%) had 85.2% sensitivity and 83.3% specificity for predicting neoplastic lesions. The area under the curve (AUC) of ROC analysis was good for relative cerebral blood volume (rCBV) and Cho/NAA ratios (> 0.80) and fair for Cho/Cr and NAA/Cr ratios (0.70–0.80). When the rCBV measurements were combined with MRS ratios, significant improvement was observed in the area under the curve (AUC) (0.969) with improved diagnostic accuracy (89.7%) and sensitivity (88.9%). Conclusions Evaluation of rCBV and metabolite ratios at MRS, particularly Cho/NAA ratio, may be helpful in differentiating low-grade gliomas from non-neoplastic lesions. The combination of dynamic susceptibility contrast (DSC) perfusion and MRS can significantly improve the diagnostic accuracy and can help avoiding the need for an invasive biopsy.

2022 ◽  
Vol 27 ◽  
pp. 1-21
Ranjit Kumar Upadhyay ◽  
Sattwika Acharya

The recent emergence of COVID-19 has drawn attention to the various methods of disease control. Since no proper treatment is available till date and the vaccination is restricted to certain age groups, also vaccine efficacy is still under progress, the emphasis has been given to the method of isolation and quarantine. This control is induced by tracing the contacts of the infectious individuals, putting them to the quarantine class and based on their symptoms, classifying them either as the susceptible or sick individuals and moving the sick individuals to the isolated class. To track the current pandemic situation of COVID-19 in India, we consider an extended Susceptible-Exposed-Quarantine-Infected-Isolated-Recovered (SEQ1IQ2R) compartmental model along with calculating its control reproductive number Rc. The disease can be kept in control if the value of Rc remains below one. This “threshold” value of Rc is used to optimize the period of quarantine, and isolation and have been calculated in order to eradicate the disease. The sensitivity analysis of Rc with respect to the quarantine and isolation period has also been done. Partial rank correlation coefficient method is applied to identify the most significant parameters involved in Rc. Based on the observed data, 7-days moving average curves are plotted for prelockdown, lockdown and unlock 1 phases. Following the trend of the curves for the infection, a generalized exponential function is used to estimate the data, and corresponding 95% confidence intervals are simulated to estimate the parameters. The effect of control measures such as quarantine and isolation are discussed. Following various mathematical and statistical tools, we systematically explore the impact of lockdown strategy in order to control the recent outbreak of COVID-19 transmission in India.

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