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1.
J Math Biol ; 86(5): 77, 2023 04 19.
Article in English | MEDLINE | ID: mdl-37074451

ABSTRACT

A discrete epidemic model with vaccination and limited medical resources is proposed to understand its underlying dynamics. The model induces a nonsmooth two dimensional map that exhibits a surprising array of dynamical behavior including the phenomena of the forward-backward bifurcation and period doubling route to chaos with feasible parameters in an invariant region. We demonstrate, among other things, that the model generates the above described phenomena as the transmission rate or the basic reproduction number of the disease gradually increases provided that the immunization rate is low, the vaccine failure rate is high and the medical resources are limited. Finally, the numerical simulations are provided to illustrate our main results.


Subject(s)
Epidemics , Vaccination , Computer Simulation , Epidemics/prevention & control , Basic Reproduction Number
2.
Sensors (Basel) ; 23(5)2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36904975

ABSTRACT

The manipulation of biomedical particles, such as separating circulating tumor cells from blood, based on standing surface acoustic wave (SSAW) has been widely used due to its advantages of label-free approaches and good biocompatibility. However, most of the existing SSAW-based separation technologies are dedicated to isolate bioparticles in only two different sizes. It is still challenging to fractionate various particles in more than two different sizes with high efficiency and accuracy. In this work, to tackle the problems of low efficiency for multiple cell particle separation, integrated multi-stage SSAW devices with different wavelengths driven by modulated signals were designed and studied. A three-dimensional microfluidic device model was proposed and analyzed using the finite element method (FEM). In addition, the effect of the slanted angle, acoustic pressure, and the resonant frequency of the SAW device on the particle separation were systemically studied. From the theoretical results, the separation efficiency of three different size particles based on the multi-stage SSAW devices reached 99%, which was significantly improved compared with conventional single-stage SSAW devices.

3.
J Math Biol ; 76(6): 1339-1356, 2018 05.
Article in English | MEDLINE | ID: mdl-28884277

ABSTRACT

In this work, we consider an epidemic model in a two-layer network in which the dynamics of susceptible-infected-susceptible process in the physical layer coexists with that of a cyclic process of unaware-aware-unaware in the virtual layer. For such multiplex network, we shall define the basic reproduction number [Formula: see text] in the virtual layer, which is similar to the basic reproduction number [Formula: see text] defined in the physical layer. We show analytically that if [Formula: see text] and [Formula: see text], then the disease and information free equilibrium is globally stable and if [Formula: see text] and [Formula: see text], then the disease free and information saturated equilibrium is globally stable for all initial conditions except at the origin. In the case of [Formula: see text], whether the disease dies out or not depends on the competition between how well the information is transmitted in the virtual layer and how contagious the disease is in the physical layer. In particular, it is numerically demonstrated that if the difference in [Formula: see text] and [Formula: see text] is greater than the product of [Formula: see text], the deviation of [Formula: see text] from 1 and the relative infection rate for an aware susceptible individual, then the disease dies out. Otherwise, the disease breaks out.


Subject(s)
Communicable Diseases/epidemiology , Communicable Diseases/transmission , Epidemics/statistics & numerical data , Models, Biological , Basic Reproduction Number , Computational Biology , Computer Simulation , Disease Susceptibility , Humans , Markov Chains , Mathematical Concepts
4.
Chaos ; 28(2): 023107, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29495668

ABSTRACT

We propose a fully cooperative coinfection model in which singly infected individuals are more likely to acquire a second disease than susceptible ones and doubly infected individuals are also assumed to be more contagious than singly infected ones. The dynamics of such a fully cooperative coinfection model is investigated through the well-mixed approach. In particular, discontinuous outbreak transitions from the disease free state or the low prevalence state to the high prevalence state can be separately observed as a disease transmission rate crosses a threshold αo from the below when the epidemic is still in the early stages. Moreover, discontinuous eradications from the high prevalence state to the low prevalence or disease free state are also separately seen as the transmission rate reaches a threshold αe(<αo) from the above when the outbreak occurs. Such phenomena constitute three types of hysteresis, where only one type has been identified before. Complete characterization of these three types of hysteresis in terms of parameters measuring the uniformity of the model is both analytically and numerically provided.


Subject(s)
Coinfection/epidemiology , Disease Outbreaks , Models, Biological , Animals , Humans , Prevalence
5.
Chaos ; 26(11): 113105, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27907992

ABSTRACT

The role of vaccine success is introduced into an epidemic spreading model consisting of three states: susceptible, infectious, and vaccinated. Moreover, the effect of three types, namely, contact, local, and global, of infection awareness and immunization awareness is also taken into consideration. The model generalizes those considered in Pastor-Satorras and Vespignani [Phys. Rev. E 63, 066117 (2001)], Pastor-Satorras and Vespignani [Phys. Rev. E 65, 036104 (2002)], Moreno et al. [Eur. Phys. J. B 26, 521-529 (2002)], Wu et al. [Chaos 22, 013101 (2012)], and Wu et al. [Chaos 24, 023108 (2014)]. Our main results contain the following. First, the epidemic threshold is explicitly obtained. In particular, we show that, for any initial conditions, the epidemic eventually dies out regardless of what other factors are whenever some type of immunization awareness is considered, and vaccination has a perfect success. Moreover, the threshold is independent of the global type of awareness. Second, we compare the effect of contact and local types of awareness on the epidemic thresholds between heterogeneous networks and homogeneous networks. Specifically, we find that the epidemic threshold for the homogeneous network can be lower than that of the heterogeneous network in an intermediate regime for intensity of contact infection awareness while it is higher otherwise. In summary, our results highlight the important and crucial roles of both vaccine success and contact infection awareness on epidemic dynamics.


Subject(s)
Vaccines , Disease Susceptibility , Epidemics , Humans , Immunization , Vaccination
6.
Chaos ; 25(4): 043116, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25933664

ABSTRACT

An SIS model based on the microscopic Markov-chain approximation is considered in this paper. It is assumed that the individual vaccination behavior depends on the contact awareness, local and global information of an epidemic. To better simulate the real situation, the vaccine failure rate is also taken into consideration. Our main conclusions are given in the following. First, we show that if the vaccine failure rate α is zero, then the epidemic eventually dies out regardless of what the network structure is or how large the effective spreading rate and the immunization response rates of an epidemic are. Second, we show that for any positive α, there exists a positive epidemic threshold depending on an adjusted network structure, which is only determined by the structure of the original network, the positive vaccine failure rate and the immunization response rate for contact awareness. Moreover, the epidemic threshold increases with respect to the strength of the immunization response rate for contact awareness. Finally, if the vaccine failure rate and the immunization response rate for contact awareness are positive, then there exists a critical vaccine failure rate αc > 0 so that the disease free equilibrium (DFE) is stable (resp., unstable) if α < αc (resp., α > αc). Numerical simulations to see the effectiveness of our theoretical results are also provided.


Subject(s)
Communicable Diseases/epidemiology , Epidemics , Immunization/methods , Vaccines , Algorithms , Computer Simulation , Humans , Markov Chains , Models, Biological , Social Support , Treatment Failure
7.
Chaos ; 24(1): 013110, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24697372

ABSTRACT

In this work, we study the cluster synchronization of chemically coupled and generally formulated networks which are allowed to be nonidentical. The sufficient condition for the existence of stably synchronous clusters is derived. Specifically, we only need to check the stability of the origins of m decoupled linear systems. Here, m is the number of subpopulations. Examples of nonidentical networks such as Hindmarsh-Rose (HR) neurons with various choices of parameters in different subpopulations, or HR neurons in one subpopulation and FitzHugh-Nagumo neurons in the other subpopulation are provided. Explicit threshold for the coupling strength that guarantees the stably cluster synchronization can be obtained.


Subject(s)
Models, Neurological , Nerve Net/physiology , Neurons/physiology , Synapses/physiology , Animals , Humans
8.
PLoS One ; 19(2): e0298708, 2024.
Article in English | MEDLINE | ID: mdl-38422071

ABSTRACT

Cross-linguistic perception is known to be molded by native and second language (L2) experiences. Yet, the role of prosodic patterns and individual characteristics on how speakers of tonal languages perceive L2 Spanish sentence modalities remains relatively underexplored. This study addresses the gap by analyzing the auditory performance of 75 Mandarin speakers with varying levels of Spanish proficiency. The experiment consisted of four parts: the first three collected sociolinguistic profiles and assessed participants' pragmatic competence and musical abilities. The last part involved an auditory gating task, where participants were asked to identify Spanish broad focus statements and information-seeking yes/no questions with different stress patterns. Results indicated that the shape of intonation contours and the position of the final stressed syllable significantly impact learners' perceptual accuracy, with effects modulated by utterance length and L2 proficiency. Moreover, individual differences in pragmatic and musical competence were found to refine auditory and cognitive processing in Mandarin learners, thereby influencing their ability to discriminate question-statement contrasts. These findings reveal the complex interplay between prosodic and individual variations in L2 speech perception, providing novel insights into how speakers of tonal languages process intonation in a non-native Romance language like Spanish.


Subject(s)
Language , Speech Perception , Humans , Linguistics , Caffeine , Contrast Media , Niacinamide
9.
Adv Mater ; 36(21): e2313456, 2024 May.
Article in English | MEDLINE | ID: mdl-38377174

ABSTRACT

All-solid-state lithium metal batteries (LMBs) are currently one of the best candidates for realizing the yearning high-energy-density batteries with high safety. However, even polyethylene oxide (PEO), the most popular polymeric solid-state electrolyte (SSE) with the largest ionic conductivity in the category so far, has significant challenges due to the safety issues of lithium dendrites, and the insufficient ionic conductivity. Herein, molecular sieve (MS) is integrated into the PEO as an inert filler with the liquid metal (LM) as a functional module, forming an "LM-MS-PEO" composite as both SSE with enhanced ionic conductivity, and protection layer against lithium dendrites. As demonstrated by theoretical and experimental investigations, LM released from MS can be uniformly and efficiently distributed in PEO, which could avoid agglomeration, enable the effective blocking of lithium dendrites, and regulate the mass transport of Li ions, thus achieving even deposition of lithium during charge/discharge. Moreover, MS could reduce the crystallinity of PEO, improve lithium-ion conductivity, and reduce operating temperature. Benefiting from the introduction of the functional MS/LM, the LM-MS-PEO electrolyte exhibits fourfold higher lithium ionic conductivity than the pristine PEO at 40 °C, while the as-assembled all-solid-state LMBs have four to five times longer stable cycle life.

10.
Chemosphere ; 339: 139755, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37567265

ABSTRACT

In order to prevent heavy metal (HM) pollution from lead smelting slag (LSS) to the surrounding environment, this work investigated the feasibility, influencing factors, and mechanisms of using industrial solid waste such as fly ash (FA), oil sludge pyrolysis residue (PR), and steel slag (SS) as remediation amendments. The results demonstrated that the stabilization process was influenced by the material dosage, water content, and LSS particle size. Compared to single materials, the combination amendment PR2FA1 (with a mass ratio of PR to FA as 2:1) exhibited the best stabilization effect, simultaneously reducing the leaching concentrations of As, Zn, Cd, and Pb in LSS to 0.032, 0.034, 0.002, and 0.014 mg/L, respectively. The pH value of the leachate remained between 8 and 9, which met the requirements of surface water quality class IV (GB3838-2002). Through morphological analysis, microscopic characterization, and simulated solution adsorption experiments, it was determined that the stabilization process of HMs was controlled by various mechanisms, including electrostatic attraction, physical adsorption, ion exchange, and chemical precipitation. PR2FA1 had more active components, and its fine-porous structure provided more active sites, resulting in good stabilization performance for As, Zn, Cd, and Pb. Furthermore, cost analysis showed that PR2FA1, as an environmentally friendly material, could generate profits of 157.2 ¥/ton. In conclusion, the prepared PR2FA1 not only addressed the HMs pollution from lead smelting slag to the surrounding environment but also achieved the safe and resourceful disposal of hazardous waste-oil sludge. Its excellent performance in stabilizing HMs and cost-effectiveness suggested promising commercial applications.


Subject(s)
Metals, Heavy , Solid Waste , Solid Waste/analysis , Industrial Waste/analysis , Cadmium/analysis , Lead/analysis , Sewage/analysis , Metals, Heavy/analysis , Coal Ash , Zinc/analysis
11.
Adv Mater ; 35(50): e2206013, 2023 Dec.
Article in English | MEDLINE | ID: mdl-35984755

ABSTRACT

All-solid-state lithium batteries (ASSLBs) employing sulfide solid electrolytes (SEs) promise sustainable energy storage systems with energy-dense integration and critical intrinsic safety, yet they still require cost-effective manufacturing and the integration of thin membrane-based SE separators into large-format cells to achieve scalable deployment. This review, based on an overview of sulfide SE materials, is expounded on why implementing a thin membrane-based separator is the priority for mass production of ASSLBs and critical criteria for capturing a high-quality thin sulfide SE membrane are identified. Moreover, from the aspects of material availability, membrane processing, and cell integration, the major challenges and associated strategies are described to meet these criteria throughout the whole manufacturing chain to provide a realistic assessment of the current status of sulfide SE membranes. Finally, future directions and prospects for scalable and manufacturable sulfide SE membranes for ASSLBs are presented.

12.
Adv Sci (Weinh) ; 10(19): e2300985, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37083269

ABSTRACT

Utilization of lithium (Li) metal anodes in all-solid-state batteries employing sulfide solid electrolytes is hindered by diffusion-related dendrite growth at high rates of charge. Engineering ex-situ Li-intermetallic interlayers derived from a facile solution-based conversion-alloy reaction is attractive for bypassing the Li0 self-diffusion restriction. However, no correlation is established between the properties of conversion-reaction-induced (CRI) interlayers and the deposition behavior of Li0 in all-solid-state lithium-metal batteries (ASSLBs). Herein, using a control set of electrochemical characterization experiments with LixAgy as the interlayer in different battery chemistries, this work identifies that dendritic tolerance in ASSLBs is susceptible to the surface roughness and electronic conductivity of the CRI-alloy interlayer. This work thereby tailors the CRI-alloy interlayer from the typical mosaic structure to a hierarchical gradient structure by adjusting the pit corrosion kinetics from the (de)solvation mechanism to an adsorption model, yielding a smooth organic-rich outer layer and a composition-regulated inorganic-rich inner layer composed mainly of lithiophilic LixAgy and electron-insulating LiF. Ultimately, desirable roughness, conductivity, and diffusivity are integrated simultaneously into the tailored CRI-alloy interlayer, resulting in dendrite-free and dense Li deposition beneath the interlayer capable of improving battery cycling stability. This work provides a rational protocol for the CRI-alloy interlayer specialized for ASSLBs.

13.
J Hazard Mater ; 452: 131253, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36966626

ABSTRACT

This study conducted a comprehensive investigation on the distribution and bioavailability of heavy metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) in sediments along two typical transects from Yangtze River to the East China Sea continental shelf that spanning large physicochemical gradients. Heavy metals were mainly associated with the fine-grained sediments (enriched with organic matter), exhibiting decreasing trends from nearshore to offshore sites. The turbidity maximum zone showed the highest metal concentrations, which evaluated as polluted for some tested metals (especially Cd) using the geo-accumulation index. Based on the modified BCR procedure, the non-residual fractions of Cu, Zn and Pb were higher within the turbidity maximum zone, and significantly negatively correlated with bottom water salinity. The DGT-labile metals all positively correlated with the acid-soluble metal fraction (especially for Cd, Zn and Cr), and negatively correlated with salinity (except Co). Therefore, our results suggest salinity as the key factor controlling metal bioavailability, which could further modulate metal diffusive fluxes at the sediment-water interface. Considering that DGT probes could readily capture the bioavailable metal fractions, and reflect the impacts of salinity, we suggest DGT technique can be used as a robust predictor for metal bioavailability and mobility in estuary sediments.

14.
Chaos ; 19(3): 033131, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19792011

ABSTRACT

Global synchronization in complex networks has attracted considerable interest in various fields. There are mainly two analytical approaches for studying such time-varying networks. The first approach is Lyapunov function-based methods. For such an approach, the connected-graph-stability (CGS) method arguably gives the best results. Nevertheless, CGS is limited to the networks with cooperative couplings. The matrix measure approach (MMA) proposed by Chen, although having a wider range of applications in the network topologies than that of CGS, works for smaller numbers of nodes in most network topologies. The approach also has a limitation with networks having partial-state coupling. Other than giving yet another MMA, we introduce a new and, in some cases, optimal coordinate transformation to study such networks. Our approach fixes all the drawbacks of CGS and MMA. In addition, by merely checking the structure of the vector field of the individual oscillator, we shall be able to determine if the system is globally synchronized. In summary, our results can be applied to rather general time-varying networks with a large number of nodes.


Subject(s)
Action Potentials/physiology , Biological Clocks/physiology , Models, Neurological , Nerve Net/physiology , Neurons/physiology , Nonlinear Dynamics , Synaptic Transmission/physiology , Animals , Computer Simulation , Feedback , Humans , Oscillometry/methods
15.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(1): 109-112, 2019 Feb 01.
Article in Zh | MEDLINE | ID: mdl-30854831

ABSTRACT

Congenital infiltrating lipomatosis of the face is a rare disorder resulting from overgrowth of adipose tissues. This condition presents gradually with swelling along with age, hypertrophy of adjacent bones, and tooth abnormalities. This study reports a case of congenital infiltrating lipomatosis of face with seizures and reviews relevant literature on the etiology, clinical symptom, diagnosis, and treatment of this condition.


Subject(s)
Lipomatosis , Seizures , Adipose Tissue , Face , Humans , Lipomatosis/complications , Seizures/complications
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 516-520, 2019 Oct 01.
Article in Zh | MEDLINE | ID: mdl-31721500

ABSTRACT

OBJECTIVE: This study aimed to construct a network of programmed celldeath ligand 1 (PD-L1) co-expression genes and screen potential biomarkers for PD-L1 expression in head and neck squamous cell carcinoma (HNSCC) by bioinformatics analysis. Moreover, the genes and pathways participating in PD-L1 and regulating the tumor immune status were determined. METHODS: The HNSCC transcriptomic dataset in TCGA was selected to retrieve gene sets on the cBioPortal platform, where PD-L1 co-expressional genes were acquired. With these genes, GO-BP, KEGG, and string analyses were performed in R clusterProfiler. Cytoscape was used for network analysis and hub gene screening. RESULTS: A total of 117 co-expression genes were obtained, most of which were enriched in immune regulation and response to viral processes. Node degree analysis indicated that STAT1, IFNG, CXCL10, CCR5, FCGR3A, CXCL9, GBP5, CD86, GZMB, IRF1 were the highest connected genes and functioned as hub genes. Survival analysis of these hub genes resulted in CCR5, CXCL9, and GZMB as the prognostic biomarkers for patients with HNSCC, all of which were involved in immune regulation and their expression levels were related to PD-L1 (Pearson correlation coefficient was 0.30, 0.35, 0.39; P<0.01). High expression levels of these three hub genes were protective factors in patients with HNSCC. CONCLUSIONS: PD-L1 co-expression hub genes are related to immunity, among which CCR5, CXCL9, and GZMB are prognostic markers with the possibility to be involved in programmed cell death protein 1 (PD-1)/PD-L1-induced tumor immune escape. These genes provide new clues to study the mechanism and precision target medicine of PD-1/PD-L1 in HNSCC.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Squamous Cell Carcinoma of Head and Neck , B7-H1 Antigen , Computational Biology , Humans , Receptors, IgG
17.
Chaos ; 17(3): 033111, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17902993

ABSTRACT

Based on the concept of matrix measures, we study global stability of synchronization in networks. Our results apply to quite general connectivity topology. In addition, a rigorous lower bound on the coupling strength for global synchronization of all oscillators is also obtained. Moreover, by merely checking the structure of the vector field of the single oscillator, we shall be able to determine if the system is globally synchronized.


Subject(s)
Algorithms , Biological Clocks/physiology , Feedback/physiology , Models, Biological , Nonlinear Dynamics , Computer Simulation
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