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1.
BMC Public Health ; 23(1): 1039, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37259046

RESUMEN

BACKGROUND: Mathematical models to forecast the risk trend of the COVID-19 pandemic timely are of great significance to control the pandemic, but the requirement of manual operation and many parameters hinders their efficiency and value for application. This study aimed to establish a convenient and prompt one for monitoring emerging infectious diseases online and achieving risk assessment in real time. METHODS: The Optimized Moving Average Prediction Limit (Op-MAPL) algorithm model analysed real-time COVID-19 data online and was validated using the data of the Delta variant in India and the Omicron in the United States. Then, the model was utilized to determine the infection risk level of the Omicron in Shanghai and Beijing. RESULTS: The Op-MAPL model can predict the epidemic peak accurately. The daily risk ranking was stable and predictive, with an average accuracy of 87.85% within next 7 days. Early warning signals were issued for Shanghai and Beijing on February 28 and April 23, 2022, respectively. The two cities were rated as medium-high risk or above from March 27 to April 20 and from April 24 to May 5, indicating that the pandemic had entered a period of rapid increase. After April 21 and May 26, the risk level was downgraded to medium and became stable by the algorithm, indicating that the pandemic had been controlled well and mitigated gradually. CONCLUSIONS: The Op-MAPL relies on nothing but an indicator to assess the risk level of the COVID-19 pandemic with different data sources and granularities. This forward-looking method realizes real-time monitoring and early warning effectively to provide a valuable reference to prevent and control infectious diseases.


Asunto(s)
COVID-19 , Humanos , Estados Unidos , COVID-19/epidemiología , SARS-CoV-2 , Pandemias/prevención & control , China/epidemiología
2.
Proc Natl Acad Sci U S A ; 115(12): E2888-E2897, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29514960

RESUMEN

Rapid antibody production in response to invading pathogens requires the dramatic expansion of pathogen-derived antigen-specific B lymphocyte populations. Whether B cell population dynamics are based on stochastic competition between competing cell fates, as in the development of competence by the bacterium Bacillus subtilis, or on deterministic cell fate decisions that execute a predictable program, as during the development of the worm Caenorhabditis elegans, remains unclear. Here, we developed long-term live-cell microscopy of B cell population expansion and multiscale mechanistic computational modeling to characterize the role of molecular noise in determining phenotype heterogeneity. We show that the cell lineage trees underlying B cell population dynamics are mediated by a largely predictable decision-making process where the heterogeneity of cell proliferation and death decisions at any given timepoint largely derives from nongenetic heterogeneity in the founder cells. This means that contrary to previous models, only a minority of genetically identical founder cells contribute the majority to the population response. We computationally predict and experimentally confirm nongenetic molecular determinants that are predictive of founder cells' proliferative capacity. While founder cell heterogeneity may arise from different exposure histories, we show that it may also be due to the gradual accumulation of small amounts of intrinsic noise during the lineage differentiation process of hematopoietic stem cells to mature B cells. Our finding of the largely deterministic nature of B lymphocyte responses may provide opportunities for diagnostic and therapeutic development.


Asunto(s)
Linfocitos B/citología , Modelos Biológicos , Animales , Apoptosis , Linfocitos B/efectos de los fármacos , Linfocitos B/fisiología , Linaje de la Célula , Proliferación Celular/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Ratones Transgénicos , Oligopéptidos/farmacología , Proteínas Proto-Oncogénicas c-bcr/genética , Análisis de la Célula Individual/métodos , Procesos Estocásticos , Imagen de Lapso de Tiempo , Flujo de Trabajo
3.
Acta Neurochir Suppl ; 126: 11-16, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29492523

RESUMEN

OBJECTIVES: We aimed to determine prognostic factors that can influence the outcome of severe traumatic brain injury (TBI) in children. MATERIALS AND METHODS: One hundred and sixty-nine patients with severe TBI were included. Consciousness was evaluated using the Glasgow Coma Scale (GCS). Severity of concomitant injuries was evaluated using the Injury Severity Score (ISS). Computer tomography (CT) scanning was used on admission and later. Intracranial injuries were classified using the Marshall CT scale. Intracranial pressure (ICP) monitoring took place in 80 cases. Serum samples of 65 patients were tested for S-100ß protein and of 43 patients for neuron specific enolase (NSE). Outcomes were evaluated 6 months after trauma using the Glasgow Outcome Scale (GOS). Statistical and mathematical analysis was conducted. The accuracy of our prognostic model was defined in another group of patients (n = 118). RESULTS: GCS, pupil size and photoreaction, ISS, hypotension and hypoxia are significant predictors of outcome of severe TBI in children. CT results complement the forecast significantly. The accuracy of surviving prognosis came to 76% (0.76) in case of S-100ß protein level ≤ 0.25 µg/l and NSE level < 19 µg/l. A mathematical model of outcome prognosis was based on discriminant function analysis. The model of prognosis was tested on the control group. The accuracy of prognosis was 86%. CONCLUSIONS: A personalised prognostic model makes it possible to predict the outcome of severe TBI in children on the first day after trauma.


Asunto(s)
Lesiones Traumáticas del Encéfalo/diagnóstico , Encéfalo/diagnóstico por imagen , Hipertensión Intracraneal/fisiopatología , Adolescente , Lesiones Traumáticas del Encéfalo/sangre , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/fisiopatología , Niño , Preescolar , Análisis Discriminante , Femenino , Escala de Coma de Glasgow , Escala de Consecuencias de Glasgow , Humanos , Puntaje de Gravedad del Traumatismo , Hipertensión Intracraneal/complicaciones , Masculino , Modelos Teóricos , Evaluación de Resultado en la Atención de Salud , Fosfopiruvato Hidratasa/sangre , Pronóstico , Estudios Retrospectivos , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Tomografía Computarizada por Rayos X
4.
Materials (Basel) ; 16(13)2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37445159

RESUMEN

The influence of electrolyte velocity over the ion-exchange membrane surface on ion and vanadium redox batteries' conductivity was formalized and quantified. The increase in electrolyte velocity dramatically improves proton conductivity, resulting in improved battery efficiency. An analysis of conductivity was carried out using a math model considering diffusion and drift ion motion together with their mass transport. The model is represented by the system of partial differential together with algebraic equations describing the steady-state mode of dynamic behavior. The theoretical solution obtained was compared qualitatively with the experimental results that prove the correctness of the submitted math model describing the influence of the electrolyte flow on the resistance of the vanadium redox battery. The presented theoretical approach was employed to conduct a parametric analysis of flow batteries, aiming to estimate the impact of electrolyte velocity on the output characteristics of these batteries.

5.
Front Endocrinol (Lausanne) ; 13: 888429, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35909562

RESUMEN

Objective: A personalized simulation tool, p-THYROSIM, was developed (1) to better optimize replacement LT4 and LT4+LT3 dosing for hypothyroid patients, based on individual hormone levels, BMIs, and gender; and (2) to better understand how gender and BMI impact thyroid dynamical regulation over time in these patients. Methods: p-THYROSIM was developed by (1) modifying and refining THYROSIM, an established physiologically based mechanistic model of the system regulating serum T3, T4, and TSH level dynamics; (2) incorporating sex and BMI of individual patients into the model; and (3) quantifying it with 3 experimental datasets and validating it with a fourth containing data from distinct male and female patients across a wide range of BMIs. For validation, we compared our optimized predictions with previously published results on optimized LT4 monotherapies. We also optimized combination T3+T4 dosing and computed unmeasured residual thyroid function (RTF) across a wide range of BMIs from male and female patient data. Results: Compared with 3 other dosing methods, the accuracy of p-THYROSIM optimized dosages for LT4 monotherapy was better overall (53% vs. 44%, 43%, and 38%) and for extreme BMI patients (63% vs. ~51% low BMI, 48% vs. ~36% and 22% for high BMI). Optimal dosing for combination LT4+LT3 therapy and unmeasured RTFs was predictively computed with p-THYROSIM for male and female patients in low, normal, and high BMI ranges, yielding daily T3 doses of 5 to 7.5 µg of LT3 combined with 62.5-100 µg of LT4 for women or 75-125 µg of LT4 for men. Also, graphs of steady-state serum T3, T4, and TSH concentrations vs. RTF (range 0%-50%) for untreated patients showed that neither BMI nor gender had any effect on RTF predictions for our patient cohort data. Notably, the graphs provide a means for estimating unmeasurable RTFs for individual patients from their hormone measurements before treatment. Conclusions: p-THYROSIM can provide accurate monotherapies for male and female hypothyroid patients, personalized with their BMIs. Where combination therapy is warranted, our results predict that not much LT3 is needed in addition to LT4 to restore euthyroid levels, suggesting opportunities for further research exploring combination therapy with lower T3 doses and slow-releasing T3 formulations.


Asunto(s)
Hipotiroidismo , Modelación Específica para el Paciente , Tiroxina , Triyodotironina , Índice de Masa Corporal , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hipotiroidismo/sangre , Hipotiroidismo/tratamiento farmacológico , Masculino , Hormonas Tiroideas/administración & dosificación , Hormonas Tiroideas/sangre , Hormonas Tiroideas/farmacología , Hormonas Tiroideas/uso terapéutico , Tirotropina/sangre , Tiroxina/administración & dosificación , Tiroxina/sangre , Tiroxina/farmacología , Tiroxina/uso terapéutico , Triyodotironina/administración & dosificación , Triyodotironina/sangre , Triyodotironina/farmacología , Triyodotironina/uso terapéutico
6.
Environ Technol ; : 1-20, 2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-35929884

RESUMEN

Global climate issues have been gaining international attention in recent years. As the largest developing country and the prime carbon emitter, the Chinese government has proposed a strategic 'double carbon' target for carbon emissions. To predict carbon emissions more accurately, clarify the future supply situation and optimise resource allocation, based on the grey MGM(1,m,N|τ) model, we introduced and applied the particle swarm algorithm to determine the time lag parameter τ and proposed a new MGM(1,m,N|τ) grey model. We give a detailed modelling procedure, including calculation steps and intelligent optimisation algorithms, by fully considering the effect of time lag. In this study, this new model is used to simulate and forecast China's carbon emissions from 2010 to 2019 and compare it with other traditional grey models and their improved time-lagged forms. The results show that the new model has significant advantages in prediction accuracy and validity, plus good prediction performance for carbon emissions, which can be extended to more macro and micro energy consumption prediction problems.

7.
Opt Quantum Electron ; 53(9): 490, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34413567

RESUMEN

The main concentration of this article is to extract pure-cubic optical solitons in nonlinear optical fiber modeled by nonlinear Schrödinger equation (NLSE). The governing model is discussed the with the effect of third-order dispersion, Kerr law of nonlinearity and without chromatic dispersion. We extract the solutions in different forms like, Jacobi's elliptic, hyperbolic, periodic, exponential function solutions including a class of solitary wave solutions such that bright, dark, singular, kink-shape, multiple-optical soliton, and mixed complex soliton solutions. Recently developed integration tools known as Φ 6 -model expansion method, generalized exponential rational function method (GERFM) and generalized Kudryashov method are applied to analyze the governing model. The studied model is also discussed by the concept of modulation instability (MI) analysis. The constraints conditions are explicitly presented for the resulting solutions and singular periodic wave solutions are recovered. Furthermore, for explaining the solutions in physical phenomena, the three dimensional, two dimensional, and their related contours graphs are plotted under the selection of appropriate parameters. The accomplished results show that the applied computational system is direct, productive, reliable and can be carried out in more complicated phenomena. The results show that the studied equation theoretically has extremely rich pure-cubic optical structures of nonlinear fiber relevance.

8.
J Inequal Appl ; 2018(1): 233, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30839661

RESUMEN

The paper studies the estimation and the portmanteau test for double AR ( p ) model with Laplace ( a , b ) distribution. The double AR ( p ) model is investigated to propose firstly the quasi-maximum exponential likelihood estimator, design a portmanteau test of double AR ( p ) on the basis of autocorrelation function, and then establish some asymptotic results. Finally, an empirical study shows that the estimation and the portmanteau test obtained in this paper are very feasible and more effective.

9.
Artículo en Zh | WPRIM | ID: wpr-622701

RESUMEN

This paper elaborates the creative thoughts on the medical Higher Mathematics from the following three aspects: the teaching idea,course system and cultivation of students' abilities.

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