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BackgroundsThe goal of this study is to explore the transmission dynamics for recent large-scale COVID-19 outbreaks in Shaanxi Province on the Chinese mainland. Furthermore, the potential effects of the Spring Festival travel rush on the ongoing COVID-19 pandemic were depicted.MethodsThis study uses baseline data from a large cohort to investigate the characteristics of the recent COVID-19 epidemic in Shaanxi province. A cluster sampling method was used to recruit the study participants during the COVID-19 pandemic in Shaanxi province since Dec. 1st, 2022. A total of 44 sampling cluster (11 village in rural areas and 33 residences in urban areas) were chosen for enrollment of study participants. A self-developed questionnaire was applied to data collection of socio-demographic and COVID-19 pandemic related information.ResultsA total of 14,744 study participants were enrolled in the baseline survey and 12,111 completed survey data were extracted for analysis. The cumulative infection attack rate (IAR) of COVID-19 among the study participants was 84.7%. The cumulative IAR in urban and rural areas were 85.6% and 83.7%, respectively. A peak of COVID-19 self-reported diagnosis could be observed from Dec. 15th, 2022 to Jan. 1st, 2023 in the provincial level. Beside this major peak of the recent epidemic (around Dec.20th, 2022), a small but steep rise could also be identified between Jan 13thto 14th, 2023. Individuals who escaped the first wave of COVID-19 outbreaks may face danger of infection from returnees during the 2023 Spring Festival.ConclusionAccording to the COVID-19 cumulative IAR data, the herd community was primarily achieved in Shaanxi province’s urban and rural areas. The epidemic in Shaanxi province has been exacerbated by mass population movement during the Spring Festival travel rush in both urban and rural areas. Further surveillance should be performed to monitor the spread of SARS-CoV-2 infections.

Rubella occurs worldwide, causing approximately 100,000 cases annually of congenital rubella syndrome, leading to severe birth defects. Better targeting of public health interventions is needed to achieve rubella elimination goals. To that end, we measured the epidemiological characteristics and seasonal dynamic patterns of rubella and determined its association with meteorological factors in Shaanxi Province, China. Data on rubella cases in Shaanxi Province from 2005 to 2018 were obtained from the Chinese National Notifiable Disease Reporting System. The Morlet wavelet analysis was used to estimate temporal periodicity of rubella incidence. Mixed generalized additive models were used to measure associations between meteorological variables (temperature and relative humidity) and rubella incidence. A total of 17,185 rubella cases were reported in Shaanxi during the study period, for an annual incidence of 3.27 cases per 100,000 population. Interannual oscillations in rubella incidence of 0.8–1.4 years, 3.8–4.8 years, and 0.5 years were detected. Both temperature and relative humidity exhibited nonlinear associations with the incidence of rubella. The accumulative relative risk of transmission for the overall pooled estimates was maximized at a temperature of 0.23°C and relative humidity of 41.6%. This study found that seasonality and meteorological factors have impact on the transmission of rubella; public health interventions to eliminate rubella must consider periodic and seasonal fluctuations as well as meteorological factors.

Background Mosquitoes host and transmit numerous arthropod-borne viruses (arboviruses) that cause disease in both humans and animals. Effective surveillance of virome profiles in mosquitoes is vital to the prevention and control of mosquito-borne diseases in northwestern China, where epidemics occur frequently. Methods Mosquitoes were collected in the Shaanxi-Gansu-Ningxia region (Shaanxi Province, Gansu Province, and Ningxia Hui Autonomous Region) of China from June to August 2019. Morphological methods were used for taxonomic identification of mosquito species. High-throughput sequencing and metagenomic analysis were used to characterize mosquito viromes. Results A total of 22,959 mosquitoes were collected, including Culex pipiens (45.7%), Culex tritaeniorhynchus (40.6%), Anopheles sinensis (8.4%), Aedes (5.2%), and Armigeres subalbatus (0.1%). In total, 3,014,183 (0.95% of clean reads) viral sequences were identified and assigned to 116 viral species (including pathogens such as Japanese encephalitis virus and Getah virus) in 31 viral families, including Flaviviridae, Togaviridae, Phasmaviridae, Phenuiviridae, and some unclassified viruses. Mosquitoes collected in July (86 species in 26 families) showed greater viral diversity than those from June and August. Culex pipiens (69 species in 25 families) and Culex tritaeniorhynchus (73 species in 24 families) carried more viral species than Anopheles sinensis (50 species in 19 families) or Aedes (38 species in 20 families) mosquitoes. Conclusion Viral diversity and abundance were affected by mosquito species and collection time. The present study elucidates the virome compositions of various mosquito species in northwestern China, improving the understanding of virus transmission dynamics for comparison with those of disease outbreaks., Author summary Most traditional viral research methods are limited to screening for a few types of viruses with low throughput. Here, we relied on metagenomic sequencing, which is a broadly non-specific screen for any virus, for monitoring of mosquito-borne viruses in the Shaanxi-Gansu-Ningxia region of China in 2019. The baseline of viral abundance and diversity in local Culex pipiens, Culex tritaeniorhynchus, Anopheles sinensis, and Aedes mosquitoes were investigated, with 116 viral species identified in 31 viral families, including Flaviviridae, Togaviridae, Phasmaviridae, Phenuiviridae, and some unclassified viruses. This study provides a baseline survey of the viromes of mosquitoes in the study area, highlighting the necessity of strengthened monitoring of mosquito-borne pathogens.

The reported coverage with two doses of the measles vaccine (MCV) in Shaanxi Province, China, is greater than 95%, but the measles incidence over the whole province remains high. Cross-sectional serological surveys of measles antibodies in Shaanxi Province were conducted in 2016 to assess the population's immunity. The measles IgG levels were measured in serum samples using ELISA. The geometric means concentration (GMC) levels and seroprevalence rates with 95% CIs were calculated by region, gender, and age. A total of 3574 serum samples were collected from participants aged from 2 months to 49 years. The GMC of measles antibodies was 471.3 mIU/ml (95% CI: 445.9-498.2 mIU/ml), and the seroprevalence was only 85.9% (95% CI: 84.8-87.1%). A significant difference in the GMC (P .05) but not the seroprevalence (P .05) was observed among the 3 regions. The report measles incidences were high in individuals aged 0-7 months (33.2/100 000) and 8-17 months (26.8/100 000). Although both measles immunity (90.7%) and MCV coverage (89.7%) were low in children aged 8-17 months, the measles seroprevalence in adults was high at greater than 90%. These results revealed that further actions may be taken to increase vaccination coverage in children aged 8 months to 5 years over the whole province and teenagers in the south region. In particular, timely administration of the first MCV dose should be emphasized to prevent measles epidemics in children aged 8-17 months. Vaccination strategies may be varied by age and region.

Background: With the progress of global climate change and more extreme weather events, areas with lower mosquito borne disease incidence also meet with resurgence of disease. This study examined t...

This paper introduces the concept of fuzzy set and proposes a fuzzy cerebellar model for robotic manipulator control by combining the cerebellar model with the fuzzy theory. This model introduces the membership degree of fuzzy set into the input layer of cerebellar model to reflect the objective world more accurately. It can not only move the arm along a specific path like a bionic cerebellar model, but also have higher integrity. The corresponding simulation experiments are carried out using the MATLAB platform and the experimental results show that the new model can control the arm exactly like the cognitive cerebellar model after several studies, and has higher control accuracy.

Temporal coordination neural modeling with Cognition between arm movement and grasping movement for gesture tracking is one of the most challenging problems in human-computer interaction. Taking into account the temporal coordination control mechanism between arm extensions and grasping during the 3D hand gesture tracking, this paper studies the properties of cognitive psychology of arm movement in hand tracking. Based on the classic arm extension and grasping neural models, this paper firstly studies the visual channel of arm movement. Then according to the characteristics of the visual channel, this paper constructs the self-organizing neural network model and cerebellar control model which is compatible with visual coordination. The simulation results show that the proposed model can effectively improve the coordination control mechanism and accuracy between arm movement and grasping.

The VITE (vector integration to end point) model is prone to be affected by the object's size, orientation and distance during the arm movement and gripping process. To address these problems, we aim to minimize the number of disturbed basic components of arm movement, grip aperture and hand orientation. Based on the cognitive theory and the characteristics of the operational 3-D hand tracking cognitive model, this paper proposes a divide-and-conquer model capable of indicating the current grasping status and switching on/off the three basic components. This model is a token ring-based status classifier. After being integrated into the VITE model, it can simulate kinetic features during arm movement and grasping process more effectively, and it is more intelligent when we construct mutually independent simulation modules of arm movement and hand orientation for the visual channels. Simulation results demonstrate the superiority of the proposed model over other models mentioned in this paper in terms of disturbance resistance.

Mainly used to simulate and describe the brain involved in speech production and speech comprehension relevant functional areas, the DIVA model simulates channel activity by a neural network model of adaptive words, syllables or phonemes, and it depends on the background of the language are 29 basic English phonemes. Since that the pronunciation of Chinese and English is very different, the basic phoneme of more than 70, while the process is completely different from the brain mechanism. If you want to “read” the Chinese brain thinking process, the need for specialized research on China's background to adapt to the DIVA model. This paper based on the DIVA model can simulate and describe the function of language generation and acquisition of relevant brain areas. By means of linear prediction and cepstrum Mel combination (LPMCC), the double vowel resonance peak frequency was extracted by fitting polynomial, and the DIVA 9 typical Chinese double vowels were simulated. The simulation results show that the model is very effective in distinguishing the vowels of Chinese vowels and the sounds of speech by adjusting the function of the resonance peaks and the corresponding parameters of the vocal organs of the vocal organs. This work provides a great theoretical and practical basis for the widespread use of intelligent robots in society.

This paper presents a lumped-parameter cardiovascular simulation model based on related basic theories of fluid mechanics and electric network. This model has three sub-models: systemic circulation sub-model, pulmonary circulation sub-model and heart sub-model. We study the systemic circulation sub-model and heart sub-model and give the blood flow parameters and the mechanism of heart sounds, such as simulation waveform, systolic pressure, diastolic pressure, the ejection fraction, etc. Based on these studies, the lumped-parameter cardiovascular simulation model is constructed by integrating pulmonary circulation sub-model, blood vessels, coupled walls, etc. into the systemic circulation sub-model. We build the formula of this simulation model using state variable analysis, and obtain the results of ventricular-atria blood volume, ventricular-atria pressure and artery blood flow. The model is also used to simulate the cardiovascular system under hypertension and heart failure conditions. The simulation results indicate that the cardiovascular simulation is practical feasibility.

Background: Evidences indicated that climate and socio-demographical factors were associated with incidence of Japanese Encephalitis (JE). However, most of them did not consider seasonality when us...

Mixed noise composed by Gaussian noise and Salt-Pepper noise is an ever-present noise model in the image. This paper proposes an adaptive image mixed removal algorithm based on measure of medium truth degree(MMTD). According to the feature and density of noise, it adaptively alters the detection window size. Then it defines the predicates and establishes the relation between gray level and truth interval of predicates. Finally, uses the distance ratio function to measure the similarity degree between the considered pixel and the normal pixel in the detection window and to remove the noise pixel. By sample simulation and classic PSNR evaluation, it shows the adaptive image mixed noise removal algorithm (AdpMMTD) brings about a good performance in removing mixed noise and preserving fine details.

As a mathematical tool, DIVA(Directions Into Velocities of Articulators) model can accurately describe and simulate the functions of human brain areas responsible for speech production and understanding. However, the speech regions of interest used in DIVA model was developed based on English. For Chinese speech studies, the original regions of interest fail to reflect the brain activation state for Chinese tasks. In this paper, a functional magnetic renonance imaging study is carried out for Chinese speech processing. Based on DIVA model, it is found from the results that, compared to results concluded for English, there are different activation state in the right posterior temporal lobe and adjacent supramarginal gyrus and the bilateral ventral occipital areas. The experimental results provide a good foundation to the future Chinese speech related modification of DIVA model.

DIVA(Direction Into Velocities Articulators) model is a mathematical model which describes the effect of the brain involved in speech production and speech understanding area that plays a role. It can do the simulation of pronunciation process. It has the guiding significance of the design for phonetic brain-machine interface system. The user only need to think about what kind of language that he wants to express. The phonetic brain-machine interface system can transform it into voice directly. The article aims at the design of Chinese phonetic brain-machine interface. First of all, gather the electro encephalo gram of the Chinese enunciators when they are speaking the Chinese pinyin pronunciation. Then combine the FMRI(functional magnetic resonance imaging) test that is associated with Chinese phonetic pronunciation. Use the method of common spatial patterns (CSP) to extract the electro encephalo gram features. Then do the classification of the features by using the Support Vector Machine. The result proves that this way has the high accuracy of the brain electrical signal recognition of the Chinese people's pinyin pronunciation. It can apply to the exploitation and design of the Chinese people's brain-computer interface.

Evidence indicated that socio-environmental factors were associated with occurrence of Japanese encephalitis (JE). This study explored the association of climate and socioeconomic factors with JE (2006–2014) in Shaanxi, China. JE data at the county level in Shaanxi were supplied by Shaanxi Center for Disease Control and Prevention. Population and socioeconomic data were obtained from the China Population Census in 2010 and statistical yearbooks. Meteorological data were acquired from the China Meteorological Administration. A Bayesian conditional autoregressive model was used to examine the association of meteorological and socioeconomic factors with JE. A total of 1197 JE cases were included in this study. Urbanization rate was inversely associated with JE incidence during the whole study period. Meteorological variables were significantly associated with JE incidence between 2012 and 2014. The excessive precipitation at lag of 1–2 months in the north of Shaanxi in June 2013 had an impact on the increase of local JE incidence. The spatial residual variations indicated that the whole study area had more stable risk (0.80–1.19 across all the counties) between 2012 and 2014 than earlier years. Public health interventions need to be implemented to reduce JE incidence, especially in rural areas and after extreme weather.

Culex flavivirus (CxFV) is an insect-specific virus of the genus Flavivirus. CxFV strains have been isolated from Cx. pipiens, Cx. quinquefasciatus, and other Cx. species in Asia, Africa, North America, Central America and South America. CxFV was isolated for the first time in China in 2006. As this is a novel flavivirus, we explored the distribution and genetic characteristics of Culex flavivirus in China. A total of 46,649 mosquitoes were collected in seven provinces between 2004 and 2012 and were analysed in 871 pools. 29 CxFV RNAs from Cx. pipiens, Cx. tritaeniorhynchus, Anopheles Sinensis, and Culex spp. tested positive for CxFV in real-time RT-PCR. 6 CxFV strains were isolated from Cx. species collected in Shandong, Henan, and Shaanxi provinces, while no virus or viral RNA was detected in samples from Sichuan, Chongqing, Hubei, and Fujian. Phylogenetic analysis of the envelope gene indicated that Chinese strains formed a robust subgroup of genotype 1, together with viruses from the United States and Japan. This study demonstrates that the geographic distribution of CxFV in China is widespread, but geographical boundaries to spread are apparent. Our findings suggest that CxFV can infect various mosquito species in nature.

Direction Into Velocities of Articulators (DIVA) model can be more accurately described as a mathematical model, it shows the role of the human brain involved in speech production and speech understanding by the region, it can simulate the pronunciation process and play a key role in speech BCI design. In order to realize the speech BCI system, we used wavelet packet decomposition and support vector machine (SVM) in EEG signal processing during the speech in this study according to the forecast of DIVA model and the conclusions of DIVA-related researches. Result shows that the eigenvector extracted by the method worked out fine in the classification of EEG signal, it provided a new way to design a speech-related BCI system. In addition, the conclusions of this study also proved the forecast of brain activation during the speech of DIVA model.

DIVA (Directions into Velocities of Articulators) is a mathematical model of the processes behind speech acquisition and production, supposed to achieve a functional representation of areas in the brain that are involved in speech production and speech perception. Introducing cerebellum control mechanism into the model plays a significant role in improving the mechanism of speech acquisition and production based on DIVA model. The paper studies its learning process, and explores cerebellar contributions to the model, that is feedforward learning, sensory predictions, feedback command production and the timing of delays, and then constructs a cerebellum model that is closer to neuroanatomy and is applied to DIVA model. Simulation results show that the improved DIVA model can produce more clear and explicit speech sounds, and is more close to human-like pronunciation system. The cerebellum model that established in this paper can be applied to speech acquisition and production based on DIVA model. DOI : http://dx.doi.org/10.11591/telkomnika.v12i6.5388

Image segmentation plays an important role in medical image processing. Fuzzy c-means (FCM) is one of the popular clustering algorithms for medical image segmentation. But FCM is highly vulnerable to noise due to not considering the spatial information in image segmentation. This paper introduces medium mathematics system which is employed to process fuzzy information for image segmentation. It establishes the medium similarity measure based on the measure of medium truth degree (MMTD) and uses the correlation of the pixel and its neighbors to define the medium membership function. An improved FCM medical image segmentation algorithm based on MMTD which takes some spatial features into account is proposed in this paper. The experimental results show that the proposed algorithm is more antinoise than the standard FCM, with more certainty and less fuzziness. This will lead to its practicable and effective applications in medical image segmentation.