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The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), which is causing the coronavirus disease-2019 (COVID-19) pandemic, poses a global health threat. However, it is easy to confuse COVID-19 with seasonal influenza in preliminary clinical diagnosis. In this study, the differences between influenza and COVID-19 in epidemiological features, clinical manifestations, comorbidities and pathogen biology were comprehensively compared and analyzed. SARS-CoV-2 causes a higher proportion of pneumonia (90.67 vs. 17.07%) and acute respiratory distress syndrome (12.00 vs. 0%) than influenza A virus. The proportion of leukopenia for influenza patients was 31.71% compared with 12.00% for COVID-19 patients (P = 0.0096). The creatinine and creatine kinase were significantly elevated when there were COVID-19 patients. The basic reproductive number (R0) for SARS-CoV-2 is 2.38 compared with 1.28 for seasonal influenza A virus. The mutation rate of SARS-CoV-2 ranges from 1.12 × 10−3 to 6.25 × 10−3, while seasonal influenza virus has a lower evolutionary rate (0.60-2.00 × 10−6). Overall, this study compared the clinical features and outcomes of medically attended COVID-19 and influenza patients. In addition, the S477N and N439K mutations on spike may affect the affinity with receptor ACE2. This study will contribute to COVID-19 control and epidemic surveillance in the future.

[This corrects the article DOI: 10.1371/journal.pone.0228473.].

Previous neuroimaging research of eating disorders such as anorexia nervosa and bulimia nervosa has mainly focused on clinical patients, indicating the crucial role of intrinsic connectivity networks involved in aberrant behavioral control (i.e., executive control network), reward reactivity (i.e., basal ganglia network), and excessive self-focused and body-focused ruminations (i.e., default mode network) in the onset and maintenance of eating disturbances. However, examinations of large-scale resting-state networks that support the role of cognitive control, reward sensitivity, and self-directed thinking in disordered eating have rarely involved non-clinical samples from the general population. This study, involving a total of 693 healthy young adults (68.69% females; mean age, 18.37 years), investigated these issues by using pre-defined functional regions of interest from the executive control network, basal ganglia network, default mode network, and a seed-based region of interest-to-region of interest approach. After statistically controlling for differences in age, sex, body mass index, and head motion, we observed significant associations of higher levels of eating disorder symptoms, especially bulimia-type eating (i.e., binge eating and a combination of binge eating and compensatory behaviors, such as purging via self-induced vomiting or laxative use, and compulsive exercise), with weaker intra-network and inter-network functional synchrony. These results remained significant after excluding underweight, overweight, and obese participants. These findings suggest that these neural circuits may play a key role in the symptoms of disordered eating in healthy adults. They further reveal that the less efficient information exchange within and between intrinsic networks associated with self-referential thinking, inhibitory control, and reward sensitivity are strongly related to eating disorder symptoms.

On-demand station-based one-way carsharing is widely adopted for battery electric vehicle sharing systems, which is regarded as a supplement of urban mobility and a promising approach to the utilization of green energy vehicles. The service model of these carsharing systems allows users to select vehicles based on their own judgment on vehicle battery endurance, while users tend to pick up vehicles with the longest endurance distances. This phenomenon makes instant-access systems lose efficiency on matching available vehicles with diverse user requests and limits carsharing systems for higher capacity. We proposed a vehicle assignment method to allocate vehicles to users that maximize the utility of battery, which requires the system to enable short-term reservation rather than instant access. The methodology is developed from an agent-based discrete event simulation framework with a first-come-first-serve logic module for instant access mode and a resource matching optimization module for short-term reservation mode. Results show that the short-term reservation mode can at most serve 20% more users and create 47% more revenue than instant access mode under the scenario of this research. This paper also points out the equilibrium between satisfying more users by efficiently allocating vehicles and distracting users by disabling instant access and suggests that the reservation time could be 15 minutes.

As one of the most common sleep-related respiratory disorders, obstructive sleep apnea (OSA) is characterized by excessive snoring, repetitive apnea, arousal, sleep fragmentation, and intermittent nocturnal hypoxemia. Focused on the resting-state brain imaging techniques, we reviewed the OSA-related resting-state electroencephalogram and resting-state functional magnetic resonance imaging (rsfMRI) studies. Compared with the healthy control group, patients with OSA presented increased frontal and central δ/θ powers during resting-state wakefulness, and their slow-wave activity showed a positive correlation with apnea–hypopnea index. For rsfMRI, the prefrontal cortex and insula may be the vital regions for OSA and are strongly related to the severity of the disease. Meanwhile, some large-scale brain networks, such as the default-mode network, salience network, and central executive network, play pivotal roles in the pathology of OSA. We then discussed the contribution of resting-state brain imaging as an evaluation approach for disease interventions. Finally, we briefly introduced the effects of OSA-related physiological and mental diseases and discussed some future research directions from the perspective of resting-state brain imaging.

To investigate the early epidemic of COVID-19, a total of 176 confirmed COVID-19 cases in Shiyan city, Hubei province, China were surveyed. Our data indicated that the rate of emergence of early confirmed COVID-19 cases in Hubei province outside Wuhan was dependent on migration population, and the second-generation of patients were family clusters originating from Wuhan travelers. Epidemiological investigation indicated that the reproductive number (R0) under containment strategies was 1.81, and asymptomatic SARS-CoV-2 carriers were contagious with a transmission rate of 10.7%. Among the 176 patients, 53 were admitted to the Renmin Hospital of Hubei University of Medicine. The clinical characteristics of these 53 patients were collected and compared based on a positive RT-PCR test and presence of pneumonia. Clinical data showed that 47.2% (25/53) of COVID-19 patients were co-infected with Mycoplasma pneumoniae, and COVID-19 patients coinfected with M. pneumoniae had a higher percentage of monocytes (P < 0.0044) and a lower neutrophils percentage (P < 0.0264). Therefore, it is important to assess the transmissibility of infected asymptomatic individuals for SARS-CoV-2 transmission; moreover, clinicians should be alert to the high incidence of co-infection with M. pneumoniae in COVID-19 patients.

In traditional large-scale industrial applications of solvent extraction, there are some limitations such as low extraction efficiency, emulsification, co-extraction, and potential safety hazards. Recently, the application of microfluidic technology in solvent extraction has been dedicated to avoid the above problems effectively. However, manufacturing microchannels becomes a key problem before the application of such a new technology. In this article, the design and fabrication of a “Y”-shaped microreactor by using a three-dimensional (3D) printer, and its feasibility for extraction and separation, is illustrated. The extraction performance of a “Y”-shaped microreactor was investigated by carrying out the extraction of In3+ and Fe3+ from a sulfate solution under different experimental conditions. When the residence time was 210 s, the volume fraction of extractant (D2EHPA) was 30%, and the initial pH value of the aqueous solution was 0.7, the extraction rate of In3+ and the separation coefficient βIn/Fe were 98.07% and 1593, respectively. Remarkably, the handling capacity of the 3D-printed “Y” microreactor presented in this work with a channel length of 36 mm was superior, whereas the extraction rate of In3+ was very close to that of the previously reported microchip with a channel length of 120 mm.

In this paper we introduce and investigate the regularity properties of one-sided multilinear fractional maximal operators, both in continuous case and in discrete case. In the continuous setting, we prove that the one-sided multilinear fractional maximal operatorsMβ+andMβ−$\mathfrak{M}_\beta^{+}\; \text{and}\, \mathfrak{M}_\beta^{-}$map W1,p1 (ℝ)×· · ·×W1,pm (ℝ) into W1,q(ℝ) with 1 < p1, … , pm < ∞, 1 ≤ q < ∞ and 1/q=∑i=1m1/pi−β$1/q= \sum_{i=1}^m1/p_i-\beta$, boundedly and continuously. In the discrete setting, we show that the discrete one-sided multilinear fractional maximal operators are bounded and continuous from ℓ1(ℤ)×· · ·×ℓ1(ℤ) to BV(ℤ). Here BV(ℤ) denotes the set of functions of bounded variation defined on ℤ. Our main results represent significant and natural extensions of what was known previously.

This paper presents a new radio frequency identification(RFID) tag that based on frequency domain coding. This tag consists of a certain number of square patch resonators placed on a certain substrate. Due to the symmetry of its structure, the tag can be read from any orientation with the reader antennas. The Radar Cross Section(RCS) responding of the tag over the FCC authorizes UWB communications ranges from 3.1 to 10.6 GHz. A better frequency identification can be obtained after using the improved Matrix Pencil Method(MPM) to extract the resonance points and differential encoding algorithm analysis. Compared with the previous chipless RFID tags，a capacity of 16 bit can be reached. It has a relatively high coding capacity and better direction independent. It is more suitable for the current market demand.

A novel compact printable chipless RFID tag is presented in this paper. The tag is etched on the substrate by several right-angel-shaped regularly arranged resonators.The tag has good stability for incident waves in a variety of polarized directions. A novel chipless tag encoding method to double the encoding capacity without increasing the mutual coupling between resonators is proposed. The RFID tag operates in the UWB band, and a high encoding density of 3.3 bit/cm2 is obtained on the area of 22 mm×11 mm. RCS curve of the tag has been given by simulation, the agreement between the simulation and the theoretical analysis validates this new concept of design. These tags are single-sided，have higher data density compared to the existing printable chipless tags，and can be directly printed on the ID cards and papers.

Complementary with electroencephalograph (EEG), functional magnetic resonance imaging (fMRI), with high spatial resolution, is powerful at providing prior source locations based on actual brain physiology. It hereby can help improve the accuracy of EEG source localization. However, most of the current methods directly penalize the sources whose fMRI activation probability is low and estimate the sources activities at every time point. Thus, they do not account for the temporal interrelated and non-stationary features of electromagnetic brain signals, and some are too much dependent on the fMRI prior. Here, we propose a new fMRI informed EEG source localization method and is termed fMRI-informed spatio-temporal unifying tomography (FIST). It uses a mixed norm constraint defined in terms of time-frequency decomposition of the sources and combines it with fMRI prior. The Fast Iterative Shrinkage Thresholding Algorithm is employed to solve the optimization problem. Both simulated and real EEG data are applied to assess the performance of the proposed method. Compared with L2-norm constrained methods, FIST has the superiority brain source estimation both in the spatial and temporal domains. By virtue of the fMRI information as a prior, FIST has great improvement in spatial accuracy and computational efficiency, when comparing with the method which only uses mixed-norm constraint. In addition, FIST shows good ability to select the fMRI priors to get a better estimation without totally depending on the prior, when comparing with the method which also has fMRI prior information.

More than 10 harbour and estuarine sediment reference materials have been developed in the United States, Canada and other countries, but most of them focus on organic pollutants and radionuclide, and lack certified values. Three sediment reference materials of the Yellow river delta have been prepared in China in 2007. In order to meet the needs of offshore marine sediment geochemical surveys and resource exploration, two sediment standard materials of the Yangtze river delta were prepared according to ISO guidelines and technical standards for reference standards at the national level. Two samples were collected according to different particle sizes, and were dried and ball milled to 200 mesh. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) were used to test the homogeneity. Results show that the F values for the variance test were less than the threshold, which indicates good homogeneity. X-ray Fluorescence Spectroscopy was used for a four-time stability test in two years. No statistically significant changes were observed and the stability of the samples was good. A total of 13 accurate and reliable analytical methods were used in 12 technologically significant laboratories to finalize the contents of 53 elements. The major elements show gradient distribution with 16.42% and 11.48% of Al2O3. These two reference materials have multiple elements with determined values by accurate and reliable methods, which can provide quality assurance for the analysis and testing during geological and environmental surveys in the Delta region.

This paper evaluates the ecological health of Shiyang River Basin by the adaptive wind-driven optimization (AWDO) algorithm and support vector regression (SVR) coupled algorithm for problems in health assessment of watershed ecosystem,finds the optimal parameters of support vector machine (SVM) by AWDO algorithm for uncertainty of parameters from SVM,proposes an evaluation model based on AWDO-SVR algorithm,and evaluates nine indexes such as water resource endowment,water resource development and utilization,and social and economic function of Shiyang River Basin by the model with advantages of fast and simple operation and no need of weight.The results show that the ecological health is sub-health for the upper reaches of Shiyang River,and morbid for the middle and lower reaches respectively.The evaluation result is the same as that of the variable set model,indicating that AWDO-SVR algorithm can be effectively applied to the ecosystem health evaluation of the river basin.

Sleep deprivation disrupted functional and structural brain areas which are associated with cognition and emotion in healthy participants. However, the effect of age on the structural changes after sleep restriction remains unclear. In the current study, gray matter volume was calculated in 43 young adults and 37 old adults before and after sleep restriction. Two-way mixed analysis of variance (between-subject factor: deprivation; within-subject factor: age) was then employed to investigate differences in gray matter volume changes between young and old adults. Gaussian random field theory was applied for multiple comparison correction. Results revealed that sleep restriction decreases gray matter volume in the right thalamus, left precuneus, and postcentral gyrus. More importantly, we found a significant deprivation × age interaction effect mainly in the right dorsal/ventral anterior insula where the gray matter volume increased in young adults after sleep restriction but showed no difference in old adults. These findings highlight the crucial role of the anterior insula in the neural mechanisms underlying sleep lose, especially among young adults. The current work provided structural evidence for describing emotional dysfunction and suggests the potential effect of age on functional and structural changes after sleep restriction.

Based on gas seepage characteristics and the basic thermo-solid-gas coupling theory, the porosity model and the dynamic permeability model of coal body containing gas were derived. Based on the relationship between gas pressure, principal stress and temperature, and gas seepage, the thermo-solid-gas coupling dynamic model was established. Initial values and boundary conditions for the model were determined. Numerical simulations using this model were done to predict the gas flow behavior of a gassy coal sample. By using the thermo-solid-gas coupling model, the gas pressure, temperature, and principal stress influence, the change law of the pressure field, displacement field, stress field, temperature field, and permeability were numerically simulated. Research results show the following: (1) Gas pressure and displacement from the top to the end of the model gradually reduce, and stress from the top to the end gradually increases. The average permeability of the YZ section of the model tends to decrease with the rise of the gas pressure, and the decrease amplitude slows down from the top of the model to the bottom. (2) When the principal stress and temperature are constant, the permeability decreases first and then flattens with the gas pressure. The permeability increases with the decrease of temperature while the gas pressure and principal stress remain unchanged.