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1.
Pharm Res ; 39(2): 295-316, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35147870

RESUMO

PURPOSE: The objective of this study was to implement computational fluid dynamics (CFD) simulations and aerosol characterization experiments to determine best-case spray drying conditions of a tobramycin excipient enhanced growth (Tobi-EEG) formulation for use in a pediatric air-jet dry powder inhaler (DPI). METHODS: An iterative approach was implemented in which sets of spray drying conditions were explored using CFD simulations followed by lead candidate selection, powder production and in vitro aerosol testing. CFD simulations of a small-particle spray dryer were performed to capture droplet drying parameters and surface-averaged temperature and relative humidity (RH) conditions in the powder collection region. In vitro aerosol testing was performed for the selected powders using the pediatric air-jet DPI, cascade impaction, and aerosol transport through a pediatric mouth-throat (MT) model to a tracheal filter. RESULTS: Based on comparisons of CFD simulations and in vitro powder performance, recommended drying conditions for small-particle powders with electrostatic collection include: (i) reducing the CFD-predicted drying parameters of κavg and κmax to values below 3 µm2/ms and 114 µm2/ms, respectively; (ii) maintaining the Collector Surface RH within an elevated range, which for the Tobi-EEG formulation with l-leucine was 20-30 %RH; and (iii) ensuring that particles reaching the collector were fully dried, based on a mass fraction of solute CFD parameter. CONCLUSIONS: Based on the newly recommended spray dryer conditions for small particle aerosols, delivery performance of the lead Tobi-EEG formulation was improved resulting in >60% of the DPI loaded dose passing through the pediatric MT model.


Assuntos
Antibacterianos/química , Modelos Químicos , Secagem por Atomização , Tobramicina/química , Administração por Inalação , Aerossóis , Antibacterianos/administração & dosagem , Antibacterianos/metabolismo , Pré-Escolar , Simulação por Computador , Composição de Medicamentos , Humanos , Hidrodinâmica , Pulmão/metabolismo , Nebulizadores e Vaporizadores , Análise Numérica Assistida por Computador , Tamanho da Partícula , Pós , Distribuição Tecidual , Tobramicina/administração & dosagem , Tobramicina/metabolismo
2.
Sci Rep ; 12(1): 171, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997036

RESUMO

The configuration of proteins is critical for their biochemical behavior. Mechanical stresses that act on them can affect their behavior leading to the development of decease. The von Willebrand factor (vWF) protein circulating with the blood loses its efficacy when it undergoes non-physiological hemodynamic stresses. While often overlooked, extensional stresses can affect the structure of vWF at much lower stress levels than shear stresses. The statistical distribution of extensional stress as it applies on models of the vWF molecule within turbulent flow was examined here. The stress on the molecules of the protein was calculated with computations that utilized a Lagrangian approach for the determination of the molecule trajectories in the flow filed. The history of the stresses on the proteins was also calculated. Two different flow fields were considered as models of typical flows in cardiovascular mechanical devises, one was a Poiseuille flow and the other was a Poiseuille-Couette flow field. The data showed that the distribution of stresses is important for the design of blood flow devices because the average stress can be below the critical value for protein damage, but tails of the distribution can be outside the critical stress regime.


Assuntos
Hemorreologia , Modelos Cardiovasculares , Fator de von Willebrand/metabolismo , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Análise Numérica Assistida por Computador , Conformação Proteica , Fluxo Sanguíneo Regional , Estresse Mecânico , Relação Estrutura-Atividade
3.
Sci Rep ; 12(1): 59, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996921

RESUMO

The silver, magnesium oxide and gyrotactic microorganism-based hybrid nanofluid flow inside the conical space between disc and cone is addressed in the perspective of thermal energy stabilization. Different cases have been discussed between the spinning of cone and disc in the same or counter wise directions. The hybrid nanofluid has been synthesized in the presence of silver Ag and magnesium oxide MgO nanoparticulate. The viscous dissipation and the magnetic field factors are introduced to the modeled equations. The parametric continuation method (PCM) is utilized to numerically handle the modeled problem. Magnesium oxide is chemically made up of Mg2+ and O2- ions that are bound by a strong ionic connection and can be made by pyrolyzing Mg(OH)2 (magnesium hydroxide) and MgCO3 (magnesium carbonate) at high temperature (700-1500 °C). For metallurgical, biomedical and electrical implementations, it is more efficient. Similarly, silver nanoparticle's antibacterial properties could be employed to control bacterial growth. It has been observed that a circulating disc with a stationary cone can achieve the optimum cooling of the cone-disk apparatus while the outer edge temperature remains fixed. The thermal energy profile remarkably upgraded with the magnetic effect, the addition of nanoparticulate in base fluid and Eckert number.


Assuntos
Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Óxido de Magnésio/química , Nanopartículas Metálicas , Modelos Teóricos , Nanocompostos , Nanotecnologia/instrumentação , Compostos de Prata/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Magnésio/química , Hidróxido de Magnésio/química , Óxido de Magnésio/farmacologia , Campos Magnéticos , Movimento (Física) , Análise Numérica Assistida por Computador , Compostos de Prata/farmacologia , Temperatura , Fatores de Tempo , Viscosidade
4.
Ann Vasc Surg ; 79: 310-323, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34648855

RESUMO

BACKGROUND: The objective of this study was to develop a method to evaluate the effects of an aortic dissection on hemodynamic parameters by conducting a comparison with that of a healthy (nondissected) aorta. Open-source software will be implemented, no proprietary software/application will be used to ensure accessorily and repeatability, in all the data analysis and processing. Computed tomography (CT) images of aortic dissection are used for the model geometry segmentation. Boundary conditions from literature are implemented to computational fluid dynamics (CFD) to analyze the hemodynamic parameters. METHODS: A numerical simulation model was created by obtaining accurate 3-dimensional geometries of aortae from CT images. In this study, CT images of 8 cases of aortic dissection (Stanford type-A and type-B) and 3 cases of healthy aortae are used for the actual aorta model geometry segmentation. These models were exported into an open-source CFD software, OpenFOAM, where a simplified pulsating flow was simulated by controlling the flow pressure. Ten cycles of the pulsatile flow (0.50 sec/cycle) conditions, totaling 5 sec, were calculated. RESULTS: The pressure distribution, wall shear stress (WSS) and flow velocity streamlines within the aorta and the false lumen were calculated and visualized. It was found that the flow velocity and WSS had a high correlation in high WSS areas of the intermittent layer between the true and false lumen. Most of the Stanford type-A dissections in the study showed high WSS, over 38 Pa, at the systole phase. This indicates that the arterial walls in type-A dissections are more likely to be damaged with pulsatile flow. CONCLUSIONS: Using CFD to estimate localized high WSS areas may help in deciding to treat a type-A or B dissection with a stent graft to prevent a potential rupture.


Assuntos
Aneurisma Dissecante/fisiopatologia , Aorta/fisiopatologia , Aneurisma Aórtico/fisiopatologia , Hemodinâmica , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/terapia , Aorta/diagnóstico por imagem , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/terapia , Aortografia , Estudos de Casos e Controles , Tomada de Decisão Clínica , Angiografia por Tomografia Computadorizada , Humanos , Hidrodinâmica , Análise Numérica Assistida por Computador , Prognóstico
5.
NMR Biomed ; 35(1): e4610, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34636458

RESUMO

Chemical exchange saturation transfer (CEST) methods measure the effect of magnetization exchange between solutes and water. While CEST methods are often implemented using a train of off-resonant shaped RF pulses, they are typically analyzed as if the irradiation were continuous. This approximation does not account for exchange of rotated magnetization, unique to pulsed irradiation and exploited by chemical exchange rotation transfer methods. In this work, we derive and test an analytic solution for the steady-state water signal under pulsed irradiation by extending a previous work to include the effects of pulse shape. The solution is largely accurate at all offsets, but this accuracy diminishes at higher exchange rates and when applying pulse shapes with large root-mean-squared to mean ratios (such as multi-lobe sinc pulses).


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Análise Numérica Assistida por Computador , Estudos de Validação como Assunto
6.
Microvasc Res ; 139: 104241, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508788

RESUMO

The present study considers the mathematical modeling of unsteady non-Newtonian hydro-magnetic nano-hemodynamics through a rigid cylindrical artery featuring two different stenoses (composite and irregular). The Ostwald-De Waele power-law fluid model is adopted to simulate the non-Newtonian characteristics of blood. Inspired by drug delivery applications for cardiovascular treatments, blood is considered doped with a homogenous suspension of biocompatible nanoparticles. The arterial vessel exhibits the permeability effect (lateral influx/efflux), and an external magnetic field is also applied in the radial direction to the flow. A combination of the Buongiorno and Tiwari-Das nanoscale models is adopted. The strongly nonlinear nature of the governing equations requires a robust numerical method, and therefore the finite difference technique is deployed to solve the resulting equations. Validation of solutions for the pure blood case (absence of nanoparticles) is included. Comprehensive solutions are presented for shear-thickening (n = 1.5) and shear-thinning (n = 0.5) blood flow for the effects of crucial nanoscale thermophysical, solutal parameters, and hydrodynamic parameters. Comparison of profiles (velocity, temperature, wall shear stress, and flow rate) is also made for composite and irregular stenosis. Colour visualization of streamline plots is included for pure blood and nano mediated blood both with and without applied magnetic field. The inclusion of nanoparticles (Cu/blood) within blood increases the axial velocity of blood. By applying external magnetic field in the radial direction, axial velocity is significantly damped whereas much less dramatic alterations are computed in blood temperature and concentration profiles. The simulations are relevant to the diffusion of nano-drugs in magnetic targeted treatment of stenosed arterial diseases.


Assuntos
Artérias/fisiopatologia , Portadores de Fármacos , Hemodinâmica , Modelos Cardiovasculares , Nanopartículas , Análise Numérica Assistida por Computador , Preparações Farmacêuticas/sangue , Doenças Vasculares/tratamento farmacológico , Artérias/patologia , Simulação por Computador , Constrição Patológica , Composição de Medicamentos , Análise de Elementos Finitos , Humanos , Permeabilidade , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Doenças Vasculares/patologia , Doenças Vasculares/fisiopatologia
7.
Microvasc Res ; 139: 104250, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516982

RESUMO

This paper presents an investigation on the interstitial fluid pressure and stress reductions in a vascularized solid tumor using a thermal therapy approach. The solid tumor is modeled as a fluid infiltrated poroelastic medium with a pressure source subjected to spatial heating. The distributions of temperature, interstitial fluid pressure, strains and stresses in a spherical tumor are obtained using a thermoporoelasticity theory in which the extracellular solid matrix and the interstitial fluid have different coefficient of thermal expansion (CTE). The numerical results for a solid tumor subjected to uniform spatial heating indicate that the CTE of the solid matrix of the tumor plays a crucial role in the reductions in the fluid pressure and effective stresses caused by the thermal therapy. The pore pressure and effective stresses are reduced when the CTE of the solid matrix is higher than that of the interstitial fluid. The reductions in fluid pressure and stresses may become significant depending on the difference between the CTEs of the solid matrix and interstitial fluid. The reductions reach the maximum at the tumor center and decrease with increasing radial distance from the tumor center. Finally, the thermally induced fluid flow is directed from the surface towards the center thereby potentially improving the microcirculation in the solid tumor.


Assuntos
Líquido Extracelular/metabolismo , Hipertermia Induzida , Microcirculação , Modelos Biológicos , Neoplasias/irrigação sanguínea , Neoplasias/terapia , Temperatura , Simulação por Computador , Módulo de Elasticidade , Neoplasias/metabolismo , Neoplasias/patologia , Análise Numérica Assistida por Computador , Porosidade , Pressão
8.
Microvasc Res ; 139: 104228, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34547346

RESUMO

The subcutaneous injection has emerged to become a feasible self-administration practice for biotherapeutics due to the patient comfort and cost-effectiveness. However, the available knowledge about transport and absorption of these agents after subcutaneous injection is limited. Here, a mathematical framework to study the subcutaneous drug delivery of mAbs from injection to lymphatic uptake is presented. A three-dimensional poroelastic model is exploited to find the biomechanical response of the tissue by taking into account tissue deformation during the injection. The results show that including tissue deformability noticeably changes tissue poromechanical response due to the significant dependence of interstitial pressure on the tissue deformation. Moreover, the importance of the amount of lymph fluid at the injection site and the injection rate on the drug uptake to lymphatic capillaries is highlighted. Finally, variability of lymphatic uptake due to uncertainty in parameters including tissue poromechanical and lymphatic absorption parameters is evaluated. It is found that interstitial pressure due to injection is the major contributing factor in short-term lymphatic absorption, while the amount of lymph fluid at the site of injection determines the long-term absorption of the drug. Finally, it is shown that the lymphatic uptake results are consistent with experimental data available in the literature.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Linfa/metabolismo , Modelos Biológicos , Absorção Fisiológica , Anticorpos Monoclonais/metabolismo , Transporte Biológico , Simulação por Computador , Difusão , Módulo de Elasticidade , Humanos , Injeções Subcutâneas , Análise Numérica Assistida por Computador , Porosidade , Pressão , Autoadministração , Fatores de Tempo
9.
Microvasc Res ; 139: 104262, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656560

RESUMO

Nanoparticle-based drug targeting is an important platform for the treatment of cardiovascular disorders. Magnetic drug targeting is more significant as it is a noninvasive procedure and biocompatible. The present problem aims to understand magnetic drug delivery to a specific location in a permeable blood vessel under the vibration and magnetic environment. Caputo-Fabrizio fractional-order time derivatives are used in the governing equations. The momentum equations are solved analytically and presented in the form of Lorenzo-Hartley and Robotonov-Hartley functions and convolution of the Laplace transform. Convolution integrations are solved by using the numerical integration technique. The Fourth order Runge-Kutta method (RK4) is used to solve the force balance equation. The influence of pertinent parameters such as Reynolds number, pulsatile frequency, magnetic field strength, Darcy number and fractional-order parameters are presented through graphs. It is observed that increasing Reynolds number results in decreasing the tendency of the drug to capture near the tumor site, whereas the pulsatile frequency presents an opposite phenomenon. Increasing the magnetic field strength and Darcy number boosts the capture efficiency of drug particles near the tumor site. The short memory effect efficiently captures the magnetic drug carriers to a specific location under the action of suitable magnetic field strength.


Assuntos
Antineoplásicos/sangue , Vasos Sanguíneos/metabolismo , Portadores de Fármacos , Campos Magnéticos , Nanopartículas Metálicas , Modelos Cardiovasculares , Neoplasias/irrigação sanguínea , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Simulação por Computador , Composição de Medicamentos , Nanotecnologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Análise Numérica Assistida por Computador , Permeabilidade , Fluxo Sanguíneo Regional
10.
PLoS One ; 16(12): e0261213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34905572

RESUMO

The determination of the relation between a number and a numerical interval is one of the core problems in the scientific calculation of privacy protection. The calculation of the relationship between two numbers and a numerical interval to protect privacy is also the basic problem of collaborative computing. It is widely used in data queries, location search and other fields. At present, most of the solutions are still fundamentally limited to the integer level, and there are few solutions at the real number level. To solve these problems, this paper first uses Bernoulli inequality generalization and a monotonic function property to extend the solution to the real number level and designs two new protocols based on the homomorphic encryption scheme, which can not only protect the data privacy of both parties involved in the calculation, but also extend the number domain to real numbers. In addition, this paper designs a solution to the confidential cooperative determination problem between real numbers by using the sign function and homomorphism multiplication. Theoretical analysis shows that the proposed solution is safe and efficient. Finally, some extension applications based on this protocol are given.


Assuntos
Algoritmos , Segurança Computacional/normas , Modelos Teóricos , Análise Numérica Assistida por Computador , Privacidade , Humanos
11.
Cells ; 10(11)2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34831187

RESUMO

Ascorbate is an important element of a variety of cellular processes including the control of reactive oxygen species levels. Since reactive oxygen species are implicated as a key factor in tumorigenesis and antitumor therapy, the injection of a large amount of ascorbate is considered beneficial in cancer therapy. Recent studies have shown that ascorbate can cross the plasma membrane through passive diffusion. In contrast to absorption by active transport, which is facilitated by transport proteins (SVCT1 and SVCT2). The passive diffusion of a weak acid across membranes depends on the electrostatic potential and the pH gradients. This has been used to construct a new theoretical model capable of providing steady-state ascorbate concentration in the intracellular space and evaluating the time needed to reach it. The main conclusion of the analysis is that the steady-state intracellular ascorbate concentration weakly depends on its serum concentration but requires days of exposure to saturate. Based on these findings, it can be hypothesized that extended oral ascorbate delivery is possibly more effective than a short intravenous infusion of high ascorbate quantities.


Assuntos
Ácido Ascórbico/metabolismo , Espaço Intracelular/metabolismo , Potenciais da Membrana/fisiologia , Neoplasias/terapia , Linhagem Celular Tumoral , Espaço Extracelular/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos , Análise Numérica Assistida por Computador , Transportadores de Sódio Acoplados à Vitamina C/metabolismo , Fatores de Tempo
12.
PLoS One ; 16(11): e0258861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34808660

RESUMO

In this paper, a mathematical model based on spherical differential unit cell is proposed as a model for studying seasonal freeze-thaw soil space infinitesimal differential unit cell. From this model, the basic equations of permafrost moisture and heat flow motion are directly derived, then the linked equations form the permafrost water-heat coupled transport model. On this basis, the one-dimensional seasonal permafrost water-heat transport equation is derived. The model reduces the original spatial three-variable coordinate system (parallel hexahedron) into a coupled equation with a single spherical radius (R) as the independent variable, so the iterations of the numerical simulation algorithm is greatly reduced and the complexity is decreased. Finally, the model is used to simulate the seasonal freeze-thaw soil in the ShiHeZi region of Xinjiang, China. The principle of the simulation is to collect the soil temperature and humidity values of the region in layers and fixed-points using a homemade freeze-thaw soil sensor, after that we solve it by numerical calculation using MATLAB. The analysis results show that the maximum relative error of the model we proposed is 4.36, the minimum error is 0.98, and the average error is 2.515. The numerical simulation results are basically consistent with the measured data, then the proposed model is consistent with the matching states of permafrost moisture content and soil temperature in the region at different times. In addition, the experiments also demonstrate the reliability and accuracy of the model.


Assuntos
Simulação por Computador , Congelamento , Modelos Teóricos , Análise Numérica Assistida por Computador , Estações do Ano , Solo , Temperatura , Água , Difusão , Eletricidade , Umidade , Gelo , Vapor
13.
J Adv Res ; 32: 99-108, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34484829

RESUMO

Introduction: Fractional operators find their applications in several scientific and engineering processes. We consider a fractional guava fruit model involving a non-local additionally non-singular fractional derivative for the interaction into guava pests and natural enemies. The fractional guava fruit model is considered as a Lotka-Volterra nature. Objectives: The main objective of this work is to study a guava fruit model associated with a non-local additionally non-singular fractional derivative for the interaction into guava pests and natural enemies. Methods: Existence and uniqueness analysis of the solution is evaluated effectively by using Picard Lindelof approach. An approximate numerical solution of the fractional guava fruit problem is obtained via a numerical scheme. Results: The positivity analysis and equilibrium analysis for the fractional guava fruit model is discussed. The numerical results are demonstrated to prove our theoretical results. The graphical behavior of solution of the fractional guava problem at the distinct fractional order values and at various parameters is discussed. Conclusion: The graphical behavior of solution of the fractional guava problem at the distinct fractional order values and at various parameters shows new vista and interesting phenomena of the model. The results are indicating that the fractional approach with non-singular kernel plays an important role in the study of different scientific problems. The suggested numerical scheme is very efficient for solving nonlinear fractional models of physical importance.


Assuntos
Modelos Teóricos , Controle Biológico de Vetores/métodos , Psidium , Animais , Humanos , Análise Numérica Assistida por Computador , Comportamento Predatório
14.
PLoS One ; 16(8): e0256584, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34437594

RESUMO

The process of integrating observations into a numerical model of an evolving dynamical system, known as data assimilation, has become an essential tool in computational science. These methods, however, are computationally expensive as they typically involve large matrix multiplication and inversion. Furthermore, it is challenging to incorporate a constraint into the procedure, such as requiring a positive state vector. Here we introduce an entirely new approach to data assimilation, one that satisfies an information measure and uses the unnormalized Kullback-Leibler divergence, rather than the standard choice of Euclidean distance. Two sequential data assimilation algorithms are presented within this framework and are demonstrated numerically. These new methods are solved iteratively and do not require an adjoint. We find them to be computationally more efficient than Optimal Interpolation (3D-Var solution) and the Kalman filter whilst maintaining similar accuracy. Furthermore, these Kullback-Leibler data assimilation (KL-DA) methods naturally embed constraints, unlike Kalman filter approaches. They are ideally suited to systems that require positive valued solutions as the KL-DA guarantees this without need of transformations, projections, or any additional steps. This Kullback-Leibler framework presents an interesting new direction of development in data assimilation theory. The new techniques introduced here could be developed further and may hold potential for applications in the many disciplines that utilize data assimilation, especially where there is a need to evolve variables of large-scale systems that must obey physical constraints.


Assuntos
Algoritmos , Análise de Dados , Simulação por Computador , Análise Numérica Assistida por Computador
15.
PLoS One ; 16(8): e0255081, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34403423

RESUMO

The sustainability of stock price fluctuations indicated by many empirical studies hardly reconciles with the existing models in standard financial theories. This paper proposes a recursive dynamic asset pricing model based on the comprehensive impact of the sentiment investor, the information trader and the noise trader. The dynamic process of the asset price is characterized and a numerical simulation of the model is provided. The model captures the features of the actual stock price that are consistent with the empirical evidence on the sustainability of stock price fluctuations. It also offers a partial explanation for other financial anomalies, for example, asset price's overreaction, asset bubble and the financial crisis. The major finding is that investor sentiment is the key factor to understand the sustainability of stock price fluctuations.


Assuntos
Investimentos em Saúde/economia , Modelos Econômicos , China , Simulação por Computador , Custos e Análise de Custo/economia , Análise Numérica Assistida por Computador
16.
PLoS One ; 16(8): e0255259, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34351973

RESUMO

In response to the soaring needs of human mobility data, especially during disaster events such as the COVID-19 pandemic, and the associated big data challenges, we develop a scalable online platform for extracting, analyzing, and sharing multi-source multi-scale human mobility flows. Within the platform, an origin-destination-time (ODT) data model is proposed to work with scalable query engines to handle heterogenous mobility data in large volumes with extensive spatial coverage, which allows for efficient extraction, query, and aggregation of billion-level origin-destination (OD) flows in parallel at the server-side. An interactive spatial web portal, ODT Flow Explorer, is developed to allow users to explore multi-source mobility datasets with user-defined spatiotemporal scales. To promote reproducibility and replicability, we further develop ODT Flow REST APIs that provide researchers with the flexibility to access the data programmatically via workflows, codes, and programs. Demonstrations are provided to illustrate the potential of the APIs integrating with scientific workflows and with the Jupyter Notebook environment. We believe the platform coupled with the derived multi-scale mobility data can assist human mobility monitoring and analysis during disaster events such as the ongoing COVID-19 pandemic and benefit both scientific communities and the general public in understanding human mobility dynamics.


Assuntos
Disseminação de Informação/métodos , Dinâmica Populacional/tendências , Big Data , COVID-19/epidemiologia , Humanos , Modelos Estatísticos , Análise Numérica Assistida por Computador , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Dinâmica Populacional/estatística & dados numéricos , Reprodutibilidade dos Testes , SARS-CoV-2/patogenicidade , Fluxo de Trabalho
17.
Sci Rep ; 11(1): 15589, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341373

RESUMO

Water removal which is a key treatment goal of automated peritoneal dialysis (APD) can be assessed cycle-by-cycle using remote patient monitoring (RPM). We analysed ultrafiltration patterns during night APD following a dry day (APDDD; no daytime fluid exchange) or wet day (APDWD; daytime exchange). Ultrafiltration for each APD exchange were recorded for 16 days using RPM in 14 patients. The distributed model of fluid and solute transport was applied to simulate APD and to explore the impact of changes in peritoneal tissue hydration on ultrafiltration. We found lower ultrafiltration (mL, median [first quartile, third quartile]) during first and second vs. consecutive exchanges in APDDD (-61 [-148, 27], 170 [78, 228] vs. 213 [126, 275] mL; p < 0.001), but not in APDWD (81 [-8, 176], 81 [-4, 192] vs. 115 [4, 219] mL; NS). Simulations in a virtual patient showed that lower ultrafiltration (by 114 mL) was related to increased peritoneal tissue hydration caused by inflow of 187 mL of water during the first APDDD exchange. The observed phenomenon of lower ultrafiltration during initial exchanges of dialysis fluid in patients undergoing APDDD appears to be due to water inflow into the peritoneal tissue, re-establishing a state of increased hydration typical for peritoneal dialysis.


Assuntos
Modelos Biológicos , Monitorização Fisiológica , Diálise Peritoneal , Peritônio/patologia , Água , Adulto , Idoso , Automação , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Numérica Assistida por Computador , Ultrafiltração , Adulto Jovem
18.
Biosci Rep ; 41(7)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34269374

RESUMO

A microfluidic array was constructed for trapping single cell and loading identical dynamic biochemical stimulation for gain a better understanding of Ca2+ signaling at single cell resolution in the present study. This microfluidic array consists of multiple radially aligned flow channels with equal intersection angles, which was designed by a combination of stagnation point flow and physical barrier. Numerical simulation results and trajectory analysis have shown the effectiveness of this single cell trapping device. Fluorescent experiment results demonstrated the effects of flow rate and frequency of dynamic stimulus on the profiles of biochemical concentration which exposed on captured cells. In this microarray, the captured single cells in each trapping channels were able to receive identical extracellular dynamic biochemical stimuli which being transmitted from the entrance in the middle of the microfluidic array. Besides, after loading dynamic Adenosine Triphosphate (ATP) stimulation on captured cells by this device, consistent average intracellular Ca2+ dynamics phase and cellular heterogeneity were observed in captured single K562 cells. Furthermore, this device is able to be used for investigating cellular respond on single cell resolution to temporally varying environments by modulating the stimulation signal in terms of concentration, pattern, and duration of exposure.


Assuntos
Trifosfato de Adenosina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Análise de Célula Única , Simulação por Computador , Humanos , Células K562 , Cinética , Microscopia de Fluorescência , Modelos Biológicos , Análise Numérica Assistida por Computador
19.
Microvasc Res ; 138: 104191, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34097918

RESUMO

This article aims to outline the characteristics of the blood flow conveying copper (Cu) and gold (Au) nanoparticles (NPs) through a non-uniform endoscopic annulus with wall slip under the action of electromagnetic force and Hall currents. The flow of blood with the suspension of hybrid nanoparticles in the annulus is induced by the peristaltic pumping. The governing equations are modeled and then simplified with the postulate of lubrication theory. The resulting non-dimensional momentum equation after simplification is solved analytically by employing the He's homotopy perturbation method (HPM) with the computational software Mathematica program (version 11). The influential role of emerging physical parameters on the physiological features related to the blood flow is inferred graphically and physically. The analytical outcomes reveal that Hall parameter has a diminishing behavior on the blood flow while the inverse impact is endured for mounting Hartmann number. Electromagnetic field and Hall currents offer a superlative mode for regulating blood flow at the time of surgery. An increment in the volume fraction of nanoparticles causes a drop in the blood temperature profile. The trapping phenomenon is also explored with the help of contours. An expansion in Hartmann number reduces the size of entrapped bolus and ultimately vanishes when Hartmann number is very large. This prospective model may be applicable in electromagnetic micro-pumps, medical simulation devices, heart-lung machine (HLM), drug carrying and drug transport systems, cancer diagnosis, tumor selective photothermal therapy, etc.


Assuntos
Vasos Sanguíneos/fisiologia , Cobre/sangue , Campos Eletromagnéticos , Endoscopia , Ligas de Ouro , Nanopartículas Metálicas , Modelos Cardiovasculares , Fluxo Pulsátil , Simulação por Computador , Análise Numérica Assistida por Computador , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Estresse Mecânico , Temperatura
20.
J Chromatogr A ; 1651: 462311, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34146960

RESUMO

Compound-specific isotope analysis of chlorine (CSIA-Cl) is a practicable and high-performance approach for revelation of transformation processes and source identification of chlorinated organic pollutants. This study conducted CSIA-Cl for typical polychlorinated organic pollutants using gas chromatography-high resolution mass spectrometry (GCHRMS) with an alternate injection mode using perchloroethylene (PCE) and trichloroethylene (TCE) as model analytes. PCE and TCE standards from two manufacturers were employed for method development, and chlorine isotope ratio calculation schemes were evaluated by experiment and numerical simulation. The achieved precision (standard deviation of isotope ratios) was up to 0.21‰ for PCE and 0.43‰ for TCE. The limits of detection for CSIA-Cl of were 0.05 µg/mL (0.05 ng on column), and the linearities were 0.05-1 µg/mL. Two isotope ratio calculation schemes, i.e., one using complete molecular isotopologues and another using the first pair of neighboring chlorine isotopologues of each analyte, were evaluated in terms of accuracy and precision. The complete-isotopologue scheme showed evidently higher precision and was more competent to reflect trueness than the isotopologue-pair scheme and the two schemes could present completely different outcomes. The method has been successfully applied to PCE and TCE reagents from different suppliers, a trichloromethane reagent, and a plastic material. The relative isotope ratio variations (Δ37Cl) of PCE and TCE in the reagents and plastic material were from -1.84±0.7‰ to 15.12±0.85‰. The analytes from different sources could mostly be discerned from each other by chlorine isotope ratios. This study will be conducive to transformation process elucidation and source identification of for PCE and TCE, and facilitate CSIA-Cl using GC-MS for more polychlorinated organic pollutants, particularly in selection and optimization of isotope ratio calculation schemes.


Assuntos
Cloro/análise , Simulação por Computador , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Halogenação , Compostos Orgânicos/análise , Fracionamento Químico , Indicadores e Reagentes , Isótopos , Análise Numérica Assistida por Computador , Plásticos/química , Padrões de Referência , Tricloroetileno/análise , Tricloroetileno/química
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