Alterations in rat brain modular organization during unconsciousness are dependent on communication efficiency and metabolic cost.

Spontaneous brain activity exhibits a highly structured modular organization that varies across individuals and reconfigures over time. Although it has been proposed that brain organization is shaped by an economic trade-off between minimizing costs and facilitating efficient information transfer, it remains untested whether modular variability and its changes during unconscious conditions might be constrained by the economy of brain organization. We acquired functional MRI and FDG-PET in rats under three different levels of consciousness induced by propofol administration. We examined alterations in brain modular variability during loss of consciousness from mild sedation to deep anesthesia. We also investigated the relationships between modular variability with glucose metabolism and functional connectivity strength as well as their alterations during unconsciousness. We observed that modular variability increased during loss of consciousness. Critically, across-individual modular variability is oppositely associated with functional connectivity strength and cerebral metabolism, and with deepening dosage of anesthesia, becoming increasingly dependent on basal metabolism over functional connectivity. These results suggested that, propofol-induced unconsciousness may lead to brain modular reorganization, which are putatively shaped by re-negotiations between energetic resources and communication efficiency.

Assessment of blood flow around the knee joint in patients with knee osteoarthritis by color Doppler ultrasound.

OBJECTIVE: To explore a method for early diagnosis of knee osteoarthritis (OA) by comparing vascular morphology and hemodynamic parameters between healthy controls and patients, and explore the effects of age on the blood flow of healthy subjects. MATERIAL AND METHODS: 80 healthy subjects and 106 patients with knee OA were recruited. Color Doppler ultrasound was used to measure the vascular morphology and hemodynamic parameters of 11 blood vessels around the knee joint. A general linear model was used to analyze the difference of blood flow parameters between healthy controls and patients, and to explore the effects of sex and age on the blood flow of healthy subjects. RESULTS: Age has no significant effect on the vessel diameter of healthy subjects, and it only affect the blood flow velocity (P ＜ 0.05) and blood flow volume (P ＜0.0083) of a few blood vessels. There was no significant difference in vascular morphological parameter between healthy controls, patients with mild OA and moderate/severe OA, but there was significant difference in vascular hemodynamic parameters (P ＜ 0.0167). Specifically, in the early stage of knee OA, hemodynamic parameters of main arteries in patients did not change significantly, but those of branch vessels changed significantly (P ＜ 0.0167). With the development of knee OA, the difference of hemodynamic parameters of branch vessels in patients increased gradually. CONCLUSION: Hemodynamic parameters of branch vessels around the knee joint have changed significantly in the early stage of knee OA, which can be treated as an important index to screening the early patients.

Assessment of Multivariate Information Transmission in Space-Time-Frequency Domain: A Case Study for EEG Signals.

OBJECTIVE: Multivariate signal (MS) analysis, especially the assessment of its information transmission (for example, from the perspective of network science), is the key to our understanding of various phenomena in biology, physics and economics. Although there is a large amount of literature demonstrating that MS can be decomposed into space-time-frequency domain information, there seems to be no research confirming that multivariate information transmission (MIT) in these three domains can be quantified. Therefore, in this study, we attempted to combine dynamic mode decomposition (DMD) and parallel communication model (PCM) together to realize it. METHODS: We first regarded MS as a large-scale system and then used DMD to decompose it into specific subsystems with their own intrinsic oscillatory frequencies. At the same time, the transition probability matrix (TPM) of information transmission within and between MS at two consecutive moments in each subsystem can also be calculated. Then, communication parameters (CPs) derived from each TPM were calculated in order to quantify the MIT in the space-time-frequency domain. In this study, multidimensional electroencephalogram (EEG) signals were used to illustrate our method. RESULTS: Compared with traditional EEG brain networks, this method shows greater potential in EEG analysis to distinguish between patients and healthy controls. CONCLUSION: This study demonstrates the feasibility of measuring MIT in the space-time-frequency domain simultaneously. SIGNIFICANCE: This study shows that MIT analysis in the space-time-frequency domain is not only completely different from the MS decomposition in these three domains, but also can reveal many new phenomena behind MS that have not yet been discovered.

Spatial distribution and risk assessment of conazole fungicides in surface seawater of the East China Sea.

Conazole fungicides (CFs), the common-used pesticide in agriculture distributed widely in the environment. This research analyzed the occurrence, potential sources, and risks of eight CFs in the East China Sea surface seawater in the early summer of 2020. The total CF concentration ranged from 0.30 to 6.20 ng/L, with an average value of 1.64 ± 1.24 ng/L. Fenbuconazole, hexaconazole, and triadimenol were the major CFs that comprised >96 % of the total concentration. The Yangtze River was identified as the significant source of CFs from the coastal regions to the off-shore inputs. Ocean current was the first-order factor controlling the content and distribution of CFs in the East China Sea. Although risk assessment revealed CFs posed a low or no substantial risk to ecology and human health, long-term monitoring was also encouraged. This study provided a theoretical foundation for assessing CFs' pollution levels and potential risks in the East China Sea.

Effects of Artificial Islands Construction on the Spatial Distribution and Risk Assessment of Heavy Metals in the Surface Sediments from a Semi-closed Bay (Longkou Bay), China.

Artificial islands construction can significantly influence the spatial distribution of heavy metals in inshore sediments. In this study, the distribution and contamination of heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Zn, As and Hg) in inshore sediments of the Longkou Bay and artificial island adjacent areas were investigated in 2013 and 2014, respectively. Results showed that the contents of heavy metals increased in the Longkou Bay and decreased in the west of the artificial island in 2014 compared with 2013. The contamination and potential eco-risk of heavy metals in the sediments were higher in 2014 than those in 2013. Cd and Hg showed a high potential eco-risk in LK02, and other metals were in the lower level. The results indicated that after the construction of artificial islands in the Longkou Bay, the contamination and eco-risk of heavy metals in the sediments markedly increased in the Longkou Bay.

Assessment of Balance Control Subsystems by Artificial Intelligence.

Recent studies have shown that balance performance assessment based on artificial intelligence (AI) is feasible. However, balance control is very complex and requires different subsystems to participate, which have not been evaluated individually yet. Furthermore, these studies only classified individual's balance performance across limited grades. Therefore, in this study we attempted to implement AI to precisely evaluate different types of balance control subsystems (BCSes). First, a total of 224 commonly used and newly developed features were extracted from the center of pressure (CoP) data for each participant, respectively. Then, regressors were employed in order to map these features to the evaluation scores given by physical therapists, which include the total score in Mini-Balance-Evaluation-Systems-Tests (Mini-BESTest) and its sub-scores on BCSes, namely anticipatory postural adjustments (APA), reactive postural control (RPC), sensory orientation (SO), and dynamic gait (DG). Their scoring ranges should be 0-28, 0-6, 0-6, 0-6, and 0-10, respectively. The results show that their minimum mean absolute errors from AI estimation reach up to 2.658, 0.827, 0.970, 0.642, and 0.98, respectively. In sum, our study is a preliminary study for assessing BCSes based on AI, which shows its possibility to be used in the clinics in the future.

Movement Symmetry Assessment by Bilateral Motion Data Fusion.

OBJECTIVE: A new approach, named bilateral motion data fusion, was proposed for the analysis of movement symmetry, which takes advantage of cross-information between both sides of the body and processes the unilateral motion data at the same time. METHODS: This was accomplished using canonical correlation analysis and joint independent component analysis. It should be noted that human movements include many categories, which cannot be enumerated one by one. Therefore, the gait rhythm fluctuations of the healthy subjects and patients with neurodegenerative diseases were employed as an example for method illustration. In addition, our model explains the movement data by latent parameters in the time and frequency domains, respectively, which were both based on bilateral motion data fusion. RESULTS: They show that our method not only reflects the physiological correlates of movement but also obtains the differential signatures of movement asymmetry in diverse neurodegenerative diseases. Furthermore, the latent variables also exhibit the potentials for sharper disease distinctions. CONCLUSION: We have provided a new perspective on movement analysis, which may prove to be a promising approach. SIGNIFICANCE: This method exhibits the potentials for effective movement feature extractions, which might contribute to many research fields such as rehabilitation, neuroscience, biomechanics, and kinesiology.

A Modified Strategy Using Barbed Sutures for Wound Closure in Total Joint Arthroplasty: A Prospective, Randomized, Double-Blind, Self-Controlled Clinical Trial.

BACKGROUND Barbed suture has reported time-saving and safety benefits for wound closure in total joint arthroplasty (TJA). However, this technique requires further investigation. The aim of this study was to use a prospective, randomized, self-controlled study to further determine the efficiency and safety of this technology and to introduce our modified suturing method through a randomized, self-controlled trial. MATERIAL AND METHODS From August 2015 to December 2016, 84 patients (hip 46, knee 38) who had undergone primary simultaneous bilateral total knee or hip arthroplasties were enrolled in this study. Barbed sutures were randomized and used on one side, and traditional sutures (Vicryl) were used on the other side. RESULTS Closure time was shorter with the barbed sutures: 6.25 min (12.00 min vs. 18.25 min, p=0.000) for hip and 5.54 min (13.18 min vs. 18.71 min, p=0.000) for knee. There was no difference in the complication rate for the 2 groups. The total cost of our suturing strategy (Quill) was 872.3 RMB, which is 375.1 RMB higher than the total cost of the standard suture method (Vicryl). However, the traditional barbed suturing method (Quill) cost 2195.6 RMB. CONCLUSIONS Barbed suturing was a fast and safe method for wound closure in TJA. We also recommend our modified suturing strategy, especially in countries where operation cost was not associated with operation time.

Spatial variation and toxicity assessment for heavy metals in sediments of intertidal zone in a typical subtropical estuary (Min River) of China.

Sediment samples were collected in five marshes (C1, Phragmites australis marsh; C2, P. australis and Cyperus malaccensis marsh; C3, C. malaccensis marsh; C4, Spartina alterniflora marsh; and C5, Cyperus compressus marsh) respectively along two typical transects (T1 and T2) extending from the vegetated marsh to the mudflat in a typical subtropical estuary (Min River) of China in July 2015 to investigate the spatial variation and toxicity of heavy metals (Pb, Cr, Cu, Zn, and Ni) in intertidal zone. Results showed that the concentrations of heavy metal in surface sediments of the two transects were in the order of Zn > Cr > Pb > Cu > Ni and slightly decreased from the land to the sea except for Pb and Zn. The levels of the five metals at C5 marsh were generally the lowest, while those of Pb, Cr, and Zn at C2 marsh were the highest. The vertical variations of Pb, Cr, and Zn concentrations in profiles differed among marshes or transects, and in most cases, there was no evidence of sediment organic matter (SOM) contributing to the sorption of significant amount of metals in sediments along the two transects, while grain composition was a primary factor controlling the spatial variations of metals. Both the vertical distributions of Cu and Ni levels among marshes or transects showed little fluctuation, which could be better explained by the effects of sulfur on the solubility and mobility of the two metals in profiles. Heavy metal levels in sediments of the Min River estuary were much higher compared with most estuaries in Asia, Europe, Africa, and South America. The sediments in intertidal zone of the Min River estuary were moderately polluted by the five metals, and particularly, Ni was identified as heavy metal of primary concern. Both Ni and Pb in sediments of the intertidal zone showed high potential toxicity and high contributions to the sum of the toxic units (ΣTUs). In future, the metal pollutions in intertidal zone of the Min River estuary might be more serious, and in the next step, there will be long-term potential consequences for endangered animals or migrant birds if measures are not taken to rehabilitate the sediments resulting from metal pollutions.

Combining FMEA with DEMATEL models to solve production process problems.

Failure mode and effects analysis (FMEA) is an analysis tool for identifying and preventing flaws or defects in products during the design and process planning stage, preventing the repeated occurrence of problems, reducing the effects of these problems, enhancing product quality and reliability, saving costs, and improving competitiveness. However, FMEA can only analyze one influence factor according to its priority, rendering this method ineffective for systems containing multiple FMs whose effects are simultaneous or interact with one another. Accordingly, when FMEA fails to identify the influence factors and the factors being influenced, the most crucial problems may be placed in lower priority or remain unresolved. Decision-Making Trial and Evaluation Laboratory (DEMATEL) facilitates the determination of cause and effect factors; by identifying the causal factors that should be prioritized, prompt and effective solutions to core problems can be derived, thereby enhancing performance. Using the photovoltaic cell manufacturing industry in China as the research target, the present study combined FMEA with DEMATEL to amend the flaws of FMEA and enhance its effectiveness. First, FMEA was used to identify items requiring improvement. Then, DEMATEL was employed to examine the interactive effects and causal relationships of these items. Finally, the solutions to the problems were prioritized. The proposed method effectively combined the advantages of FMEA and DEMATEL to facilitate the identification of core problems and prioritization of solutions in the Chinese photovoltaic cell industry.

Efficient Bayesian hierarchical functional data analysis with basis function approximations using Gaussian-Wishart processes.

Functional data are defined as realizations of random functions (mostly smooth functions) varying over a continuum, which are usually collected on discretized grids with measurement errors. In order to accurately smooth noisy functional observations and deal with the issue of high-dimensional observation grids, we propose a novel Bayesian method based on the Bayesian hierarchical model with a Gaussian-Wishart process prior and basis function representations. We first derive an induced model for the basis-function coefficients of the functional data, and then use this model to conduct posterior inference through Markov chain Monte Carlo methods. Compared to the standard Bayesian inference that suffers serious computational burden and instability in analyzing high-dimensional functional data, our method greatly improves the computational scalability and stability, while inheriting the advantage of simultaneously smoothing raw observations and estimating the mean-covariance functions in a nonparametric way. In addition, our method can naturally handle functional data observed on random or uncommon grids. Simulation and real studies demonstrate that our method produces similar results to those obtainable by the standard Bayesian inference with low-dimensional common grids, while efficiently smoothing and estimating functional data with random and high-dimensional observation grids when the standard Bayesian inference fails. In conclusion, our method can efficiently smooth and estimate high-dimensional functional data, providing one way to resolve the curse of dimensionality for Bayesian functional data analysis with Gaussian-Wishart processes.

[Economic burden and related factors on inpatients with HBV-related diseases in Shandong province].

OBJECTIVE: To investigate the economic burden of patients with acute and chronic hepatitis B, cirrhosis and liver cancer caused by hepatitis B virus (HBV). METHODS: Cluster sampling was used on cases consecutively collected during the study period. Questionnaire survey was conducted and information on the expenses during hospitalization was collected from the hospital records and through interviewing those patients. RESULTS: Yearly costs related to patients with acute hepatitis B, severe hepatitis B, chronic hepatitis B, cirrhosis, hepatocellular carcinoma were 66.7, 138.1, 127.4, 151.7 and 377.2 thousand Yuan, respectively. RESULTS: from multiple linear regression model showed that the type of medical insurance scheme, annual days of hospitalization, classifications of HBV-related diseases and personal income were major influencing factors on the cost. CONCLUSION: HBV infection caused considerable burden to families and the society, indicating that HBV infection control programs would bring huge potential benefits. The reform of insurance scheme should be administrated to promote social fairness.

Comparison of the use of pupil diameter and galvanic skin response signals for affective assessment of computer users.

The implementation of Affective Computing concepts requires the assessment of the affective states in the computer user, e.g., “relaxation” or “stress”. Traditionally, the Galvanic Skin Response (GSR) signal has been analyzed as the leading indicator of the sympathetic activation that accompanies “stress”, when it is experienced by a computer user. However, recent research has found that the Pupil Diameter (PD), which is also controlled by the Autonomic Nervous System (ANS), can be an important indicator of sympathetic activation. This paper describes techniques for the processing of the Pupil Diameter (PD) signal to detect episodes of mental stress induced in experimental subjects, differentiating them from “relaxation” intervals. Our experiments also recorded and analyzed the GSR signal from the subjects, for comparison purposes. The PD signal is first pre-processed applying wavelet denoising and Kalman filtering to remove the high-frequency variations of the raw PD signal that are not representative of the subject’s affective state. Then 3 features are extracted from the normalized, pre-processed PD signal and five different classification algorithms are applied on these features to differentiate the states of “relaxation” vs. “stress” in the computer user. Similarly, 3 GSR features were obtained and used for classification. PD-based classification achieved an average accuracy of 85.86%. GSR-based classification achieved an average accuracy of 60.66%. Therefore, the results indicate that the pupil diameter may be one of the most significant physiological signals to monitor for affective assessment and differentiation of “relaxation” vs. “stress” states of a computer user.

Affective assessment of computer users based on processing the pupil diameter signal.

Detecting affective changes of computer users is a current challenge in human-computer interaction which is being addressed with the help of biomedical engineering concepts. This article presents a new approach to recognize the affective state ("relaxation" vs. "stress") of a computer user from analysis of his/her pupil diameter variations caused by sympathetic activation. Wavelet denoising and Kalman filtering methods are first used to remove abrupt changes in the raw Pupil Diameter (PD) signal. Then three features are extracted from the preprocessed PD signal for the affective state classification. Finally, a random tree classifier is implemented, achieving an accuracy of 86.78%. In these experiments the Eye Blink Frequency (EBF), is also recorded and used for affective state classification, but the results show that the PD is a more promising physiological signal for affective assessment.

[Estimation on disease burden related to hepatitis B virus infection in Shandong province of China].

OBJECTIVE: To comprehensively measure the burden of hepatitis B, liver cirrhosis and liver cancer in Shandong province, using disability-adjusted life years (DALYs) to estimate the disease burden attribute to hepatitis B virus (HBV) infection. METHODS: Based on the mortality data of hepatitis B, liver cirrhosis and liver cancer derived from the third National Sampling Retrospective Survey for Causes of Death during 2004 and 2005, the incidence data of hepatitis B and the prevalence and the disability weights of liver cancer gained from the Shandong Cancer Prevalence Sampling Survey in 2007, we calculated the years of life lost (YLLs), years lived with disability (YLDs) and DALYs of three diseases following the procedures developed for the global burden of disease (GBD) study to ensure the comparability. RESULTS: The total burden for hepatitis B, liver cirrhosis and liver cancer were 211,616 (39,377 YLLs and 172,239 YLDs), 16,783 (13,497 YLLs and 3286 YLDs) and 247,795 (240,236 YLLs and 7559 YLDs) DALYs in 2005 respectively, and men were 2.19, 2.36 and 3.16 times as that for women, respectively in Shandong province. The burden for hepatitis B was mainly because of disability (81.39%). However, most burden on liver cirrhosis and liver cancer were due to premature death (80.42% and 96.95%). The burden of each patient related to hepatitis B, liver cirrhosis and liver cancer were 4.8, 13.73 and 11.11 respectively. CONCLUSION: Hepatitis B, liver cirrhosis and liver cancer caused considerable burden to the people living in Shandong province, indicating that the control of hepatitis B virus infection would bring huge potential benefits.