The Quantitative Analysis of Dynamic Mechanisms Impacting Gastric Cancer Cell Proliferation via Serine/glycine Conversion / 生物化学与生物物理进展

ObjectiveGastric cancer (GC) seriously affects human health and life, and research has shown that it is closely related to the serine/glycine metabolism. The proliferation ability of tumor cells is greatly influenced by the metabolism of serine and glycine. The aim of this study was to investigate the molecular mechanism of serine/glycine metabolism can affect the proliferation of gastric cancer cells. MethodsIn this work, a stable metabolic dynamic model of gastric cancer cells was established via a large-scale metabolic network dynamic modeling method in terms of a potential landscape description of stochastic and non-gradient systems. Based on the regulation of the model, a quantitative analysis was conducted to investigate the dynamic mechanism of serine/glycine metabolism affecting the proliferation of gastric cancer cells. We introduced random noise to the kinetic equations of the general metabolic network, and applied stochastic kinetic decomposition to obtain the Lyapunov function of the metabolic network parameter space. A stable metabolic network was achieved by further reducing the change in the Lyapunov function tied to the stochastic fluctuations. ResultsDespite the unavailability of a large number of dynamic parameters, we were able to successfully construct a dynamic model for the metabolic network in gastric cancer cells. When extracellular serine is available, the model preferentially consumes serine. In addition, when the conversion rate of glycine to serine increases, the model significantly upregulates the steady-state fluxes of S-adenosylmethionine (SAM) and S-adenosyl homocysteine (SAH). ConclusionIn this paper, we provide evidence supporting the preferential uptake of serine by gastric cancer cells and the important role of serine/glycine conversion rate in SAM generation, which may affect the proliferation ability of gastric cancer cells by regulating the cellular methylation process. This provides a new idea and direction for targeted cancer therapy based on serine/glycine metabolism.

Stochastic Disaggregation of Daily Rainfall Using Barlett Lewis Rectangular Pulse Model (BLRPM): A Case Study of Middle Gujarat

Having accurate and ample data on rains is the sole golden input for deciding ultimate success of any progressive efforts towards natural resource management. Ultimate conquest of any pertinent schemes on developing and managing watersheds, canals, commands, irrigation net-works, soil-erosion, soil-conservation, drylands, forests, pastures, livestock, land use changes and many ecology-based errands; is entirely governs by the precision, relevancy and quality of rainfall data. Even the ending success of present days smart hydrologic models, modelling entirely remains regulated by the precision & relevance of rainfall data used therein. Most commonly available rain data happens to be daily rain values. However, for precise planning at microscale, we need to have its finer sub-daily temporal distribution. Rainfall disaggregation is a newly emerging applied option where utilities of advanced stochastic architecture is utilized across the globe to offer desired location specific and even rainy day specific best possible temporal disaggregated outcomes. Present paper offers some of the crisped outcomes from a detailed study performed in Gujarat. The predictive ability of one of the most popular BLRP model in this regard is shared by incorporating its basic architecture followed by its predictive performances on randomised sample rainy days covering 6 explicit locations in middle Gujarat region of western India. Preliminary findings reported herein will serve as a food for thought for smarter ways of managing water, land, watersheds and ecology. The BLRP model for rainfall disaggregation has the potential to improve the accuracy of rainfall estimates, facilitate efficient water management, improve hydrological modeling, facilitate climate change analysis, and be cost-effective.

Automatic sleep staging algorithm for stochastic depth residual networks based on transfer learning / 生物医学工程学杂志

The existing automatic sleep staging algorithms have the problems of too many model parameters and long training time, which in turn results in poor sleep staging efficiency. Using a single channel electroencephalogram (EEG) signal, this paper proposed an automatic sleep staging algorithm for stochastic depth residual networks based on transfer learning (TL-SDResNet). Firstly, a total of 30 single-channel (Fpz-Cz) EEG signals from 16 individuals were selected, and after preserving the effective sleep segments, the raw EEG signals were pre-processed using Butterworth filter and continuous wavelet transform to obtain two-dimensional images containing its time-frequency joint features as the input data for the staging model. Then, a ResNet50 pre-trained model trained on a publicly available dataset, the sleep database extension stored in European data format (Sleep-EDFx) was constructed, using a stochastic depth strategy and modifying the output layer to optimize the model structure. Finally, transfer learning was applied to the human sleep process throughout the night. The algorithm in this paper achieved a model staging accuracy of 87.95% after conducting several experiments. Experiments show that TL-SDResNet50 can accomplish fast training of a small amount of EEG data, and the overall effect is better than other staging algorithms and classical algorithms in recent years, which has certain practical value.

The inverse stochastic resonance in a small-world neuronal network under electromagnetic stimulation / 生物医学工程学杂志

Electromagnetic stimulation is an important neuromodulation technique that modulates the electrical activity of neurons and affects cortical excitability for the purpose of modulating the nervous system. The phenomenon of inverse stochastic resonance is a response mechanism of the biological nervous system to external signals and plays an important role in the signal processing of the nervous system. In this paper, a small-world neural network with electrical synaptic connections was constructed, and the inverse stochastic resonance of the small-world neural network under electromagnetic stimulation was investigated by analyzing the dynamics of the neural network. The results showed that: the Levy channel noise under electromagnetic stimulation could cause the occurrence of inverse stochastic resonance in small-world neural networks; the characteristic index and location parameter of the noise had significant effects on the intensity and duration of the inverse stochastic resonance in neural networks; the larger the probability of randomly adding edges and the number of nearest neighbor nodes in small-world networks, the more favorable the anti-stochastic resonance was; by adjusting the electromagnetic stimulation parameters, a dual regulation of the inverse stochastic resonance of the neural network can be achieved. The results of this study provide some theoretical support for exploring the regulation mechanism of electromagnetic nerve stimulation technology and the signal processing mechanism of nervous system.

Protección de embarazadas en radiología oral / Protection of pregnant women in oral radiology

Las radiografías dentales son necesarias para diagnosticar y hacer seguimiento de múltiples enfermedades orales. Sin embargo, debido a los conocidos efectos estocásticos de los rayos X dentales es imprescindible garantizar protección a los pacientes. Especial atención merecen las mujeres embarazadas por cuanto el feto es altamente vulnerable a la radiación, sobre todo enlas primeras semanas. Algunas recomendaciones de protección radiológica en esta población son: El uso de radiografías ha sido justificado; realizar el estudio 10 días después del inicio de la menstruación; informar del procedimiento a la embarazada a fin de evitar el miedo; optimizar el procedimiento (haz colimado, alto kVp, control manual de disparo, calibración regular etc.) y usar delantal plomado solo si las condiciones de optimización son insuficientes

Dental x-rays are necessary to diagnose and monitor multiple oral diseases. However, due to the well-known stochastic effects of dental X-rays, it is essential to guarantee patient protection. Pregnant women deserve special attention because the fetus is highly vulnerable to radiation, especially in the first weeks. Some recommendations for radiological protection in this population are the use of radiographs has been justified; conduct the study 10 days after the onset of menstruation; inform the pregnant woman about the procedure to avoid fear; optimize the procedure (collimated beam, high kVp, manual trip control, regular calibration etc.) and use a lead apron only if the optimization conditions are insufficient.

Characterizing the magnitude of vibration imposed by stochastic whole-body vibration platforms used in rehabilitation and training: a preliminary study / Caracterização da magnitude da vibração imposta por plataformas vibratórias estocásticas de corpo inteiro utilizadas em reabilitação e treinamento: estudo preliminar

Abstract The use of devices that produce stochastic whole-body vibration as a resource for rehabilitation and training programs has been founded on the theory of stochastic resonance. However, the prescription of rehabilitation and training programs must be preceded by the verification of imposed-vibration magnitude and of how it can be affected by the presence of an individual on the devices. The aim of this research was to characterize and analyze the effect of an individual's mass on the vibratory stimulus provided by stochastic whole-body vibration (SWBV) devices. The sample consisted of 30 repetitions for each one of the 6 vibration levels of the SWBV device (level 02, 04, 06, 08, 10 and 12), performed in two experimental situations (Without Load; Load [70Kg]; ≈ 35 kg on the right and left surfaces of the platform). For the antero-posterior, latero-lateral, and vertical directions, all variables showed significant differences between treatments, levels and interaction between experimental factors (p<.05), except for the Disp variable between treatments (p=.075). To measure vibration magnitude, a triaxial accelerometer was attached at the center of the board of one of the platform surfaces. Load interferes with parameters of vibration imposed by SWBV platforms, increasing ARMS and APEAK in the latero-lateral and antero-posterior directions, reducing these same parameters in the vertical direction.

Resumo O uso de dispositivos que produzem vibração estocástica de corpo inteiro como recurso para programas de reabilitação e treinamento foi fundamentado na teoria da ressonância estocástica. Entretanto, a prescrição de programas de reabilitação e treinamento deve ser precedida da verificação da magnitude da vibração imposta e de como ela pode ser afetada pela presença de um indivíduo nos dispositivos. O objetivo deste estudo foi caracterizar e analisar o efeito da massa do indivíduo sobre o estímulo vibratório proporcionado por dispositivos de vibração estocástica de corpo inteiro. A amostra consistiu em 30 repetições para cada um dos 6 níveis de vibração de um dispositivo de vibração estocástica de corpo inteiro (nível 02, 04, 06, 08, 10 e 12), realizados em duas situações experimentais (Sem carga e Carga [70Kg], 35 kg nas superfícies direita e esquerda da plataforma). Para medir a magnitude da vibração, um acelerômetro triaxial foi fixado ao centro do assoalho de uma das superfícies da plataforma. Para os eixos ântero-posterior, látero-lateral e vertical, todas as variáveis mostraram diferenças entre tratamentos, níveis e interação entre fatores experimentais (p<.05), exceto para a variável de deslocamento pico - a - pico (Disp) entre tratamentos (p=.075). A carga interfere com parâmetros de vibração impostos sobre as plataformas de vibração estocástica de corpo inteiro, aumentando a aceleração média (ARMS) e de pico (APEAK) nas direções látero-lateral e ântero-posterior, reduzindo estes mesmos parâmetros na direção vertical.

Método estrutural para aferir o curso pandêmico do SARS-CoV-2 em ambientes escolares / A structural method to assess the course of the SARS-CoV-2 pandemic in school environments / Método estructural para examinar el curso de la pandemia por el SARS-CoV-2 en ambientes escolares

RESUMO A pandemia da COVID-19 tem levantado uma série de dilemas para os gestores públicos, sendo a reabertura das escolas uma das decisões mais complexas. O presente artigo apresenta uma microssimulação do curso da pandemia considerando vários cenários dentro dos limites de uma sala de aula na cidade de Belo Horizonte, Brasil. Utilizou-se um modelo de suscetíveis-infectados-recuperados (SIR) integrado a um modelo de grafos aleatórios, associando características epidemiológicas a fatores sociométricos e sociodemográficos. Foram utilizadas as taxas de contatos sociais projetadas para o Brasil pelo projeto europeu POLYMOD e adaptadas para a cidade de Belo Horizonte para simular o número de contatos entre os indivíduos seguindo uma distribuição de Poisson. A simulação tomou como referência 20 alunos e suas famílias. Os cenários projetados discriminaram três faixas etárias com as suas respectivas taxas diárias de contatos sociais: 0 a 5 anos (0,01), 6 a 14 anos (1,80) e 15 a 19 anos (0,20). As simulações demonstraram diferenças claras para os grupos etários considerados, dependendo do número de infectados iniciais e do uso ou não de máscara no espaço escolar. Os resultados confirmam que a ausência de medidas adequadas de mitigação eleva de forma considerável o risco de contágio na comunidade escolar.

ABSTRACT The COVID-19 pandemic has imposed several dilemmas for managers in the public sector, with school reopening being among the most complex decisions. The present article presents a microsimulation model of the pandemic course considering various scenarios within the confines of a classroom in the city of Belo Horizonte, Brazil. For that, a susceptible-infectious-recovered (SIR) model was integrated with a random graph model, associating epidemiological characteristics with sociometric and sociodemographic factors. Social contact rates projected for Brazil in the European POLYMOD project were adapted for the city of Belo Horizonte to simulate the number of contacts among individuals considering a Poisson distribution. The simulation used as reference a group of 20 students and their families. The projected scenarios discriminated three age groups with their respective rate of daily social contacts: 0 to 5 years (0.01), 6 a 14 years (1.80), and 15 to 19 years (0.20). The simulations showed clear differences between these age groups, depending on the initial number of infected individuals and on the use or not of face masks in the school. The results confirm that the absence of adequate mitigation measures entails a considerable increase in transmission in the school setting.

RESUMEN La pandemia de COVID-19 ha creado una serie de dilemas para los administradores públicos, que ha hecho de la reapertura de las escuelas una de las decisiones más complejas. En el presente artículo se presenta una microsimulación del curso de la pandemia, en la cual se analizan varias situaciones hipotéticas dentro de los límites de un salón de clases en la ciudad de Belo Horizonte (Brasil). Se utilizó un modelo de personassusceptibles, infectadas y recuperadas (SIR) integrado a un modelo de gráficos aleatorios, dentro del cual se asociaron lascaracterísticas epidemiológicas a factores sociométricos y sociodemográficos. Se utilizaron las tasas de contactos sociales previstas para Brasil por el proyecto europeo POLYMOD y adaptadas a la ciudad de Belo Horizonte con el fin de simular el número de contactos entre las personas con una distribución de Poisson. Para la simulación se tomó como referencia un grupo de 20 alumnos y sus familias. En las situaciones hipotéticas proyectadas se distinguieron tres grupos etarios con sus respectivas tasas diarias de contactos sociales: de 0 a 5 años (0,01), de 6 a 14 años (1,80) y de 15 a 19 años (0,20). Las simulaciones demostraron que hay claras diferencias en los grupos etarios analizados, según el número inicial de personas infectadas y el uso o la falta de uso de mascarilla en el ambiente escolar. Los resultados confirman que la falta de medidas adecuadas de mitigación eleva de forma considerable el riesgo de contagio en la comunidad escolar.

Regeneración de un bosque secundario afectado por el Huracán Otto en Costa Rica / Regeneration of a secondary forest affected by Hurricane Otto in Costa Rica

Resumen Introducción: Se han realizado múltiples estudios en bosques afectados por huracanes, pero la información obtenida para Costa Rica es escasa, o nula en el caso de impactos directos como lo fue Otto, por lo que es necesario ampliar el conocimiento que se tiene acerca de los efectos de estos fenómenos en bosques tropicales y los mecanismos de recuperación de estos biomas. Consecuentemente se vuelve necesario identificar la vulnerabilidad de los ecosistemas a largo plazo y cuantificar las pérdidas que se generan a diferentes escalas, producto de los intensos eventos pluviales y los fuertes vientos. Objetivo: Determinar el comportamiento y estado de la recuperación en un bosque secundario afectado directamente por el huracán Otto en Boca Tapada, Pital, San Carlos, Costa Rica. Métodos: Se establecieron 10 unidades de muestreo de 20 x 50 m distribuidas de forma sistemática dentro de un bosque secundario afectado por el huracán Otto en Boca Tapada de San Carlos. Se evaluó la condición actual del bosque, se identificaron las especies que más daño recibieron por consecuencia de los fuertes vientos, así como las que poseen capacidad de recuperarse a través de rebrotes. Se realizó un sobrevuelo con un vehículo no tripulado, y se construyó un ortomosaico que fue posteriormente digitalizado y clasificado de acuerdo con el estado de la cobertura forestal presente en tres tiempos evaluados, condición inicial, después del aprovechamiento forestal y la condición al momento de realizado el muestreo. Se comparó la densidad poblacional, diversidad y área basal con lo presentado para un bosque primario aledaño al sitio de estudio, que también fue afectado por el paso del huracán Otto. Resultados: Se obtuvo que un 69.5 % de los individuos con d ≥ 5 cm se encuentran en buen estado, un 20.3 % fue descopado y un 12.7 % inclinado sin exposición de raíces. La familia que más riqueza de especies aporta es Fabaceae, esta misma es la que más abundancia de individuos dañados posee y la que presentó mayor cantidad de especies con capacidad de rebrotar. La especie que más daños sufrió fue Couma macrocarpa (Euphorbiaceae). El área de cobertura boscosa inicial fue afectada en un 7,63 % por el aprovechamiento forestal, y en un 44.25 % por el paso del huracán Otto. Se determinó que existen diferencias significativas en la diversidad de especies (P = 0.0004; α = 0.05) y en la densidad de individuos (P = 0.0011; α = 0.05), el bosque secundario es quien posee la mayor media. No se presentaron diferencias significativas en los valores de área basal (P = 0.6951; α = 0.05). Conclusiones: Un 30,5 % de la masa forestal fue afectada por el paso del huracán Otto y la familia Fabaceae representa un papel importante en la recuperación del bosque. Además, el aprovechamiento forestal en un bosque puede aumentar el riesgo de afectación por el paso de huracanes y el bosque secundario posee mayor diversidad de especies y mayor densidad de individuos que el bosque primario.

Abstract Introduction: Multiple studies have been carried out in forests affected by hurricanes, but the information obtained for Costa Rica is scarce or null, in the case of direct impacts such as Otto, so it is necessary to expand the existing knowledge about the effects of these phenomena on tropical forests and the recovery mechanisms of these biomes. Consequently, it is necessary to identify the vulnerability of ecosystems in long term and quantify the losses that are generated at different scales, as a result of the intense events of rain and strong winds. Objective: Determining behavior and recovery status in a secondary forest directly affected by Hurricane Otto in Boca Tapada, Pital, San Carlos, Costa Rica. Methods: Ten 20 x 50 m sampling units were systematically distributed within a secondary forest affected by Hurricane Otto in Boca Tapada, San Carlos. The current condition of the forest was evaluated, the species that received the most damage due to high winds were identified, as well as those that have the capacity to recover through regrowths. An overflight was carried out with an unmanned aerial vehicle and an orthomosaic was constructed, subsequently digitized, and classified according to the state of the forest cover presented in three evaluated moments, initial condition, after logging and the condition at the time of sampling. Population density, diversity, and basal area, were compared to data obtained in an adjacent primary forest also affected by the passage of Hurricane Otto. Results: It was obtained that 69.5 % of individuals with d ≥ 5 cm are in good condition, 20.3 % were broken in the tree canopy and 12.7% inclined without exposure of the roots. The family that provided the greatest species richness is Fabaceae, which is the same with the greatest abundance of damaged individuals and the one with the highest number of species with the ability to resprouting. The species that suffered the most damage was Couma macrocarpa (Euphorbiaceae). The initial area of forest cover was reduced by 7.63 % due to logging and 44.25 % due to Hurricane Otto. It was determined that there are significant differences in species diversity (P = 0.0004; α = 0.05) and in the density of individuals (P = 0.0011; α = 0.05). The secondary forest has the highest average in both cases. There are no significant differences in the values of the basal area (P = 0.6951; α = 0.05). Conclusions: 30.5 % of the forest mass was affected by the passage of Hurricane Otto and the Fabaceae family plays an important role in forest recovery. In addition, forest harvesting in a forest can increase the risk of being affected by the passage of hurricanes and the secondary forest has a greater diversity of species and a higher density of individuals than the primary forest.

Modelagem multinomial aplicada à pesquisa em psicologia / Modelo multinomial aplicado a la investigación psicológica / Multinomial modeling applied to psychological research

Teorias sobre fenômenos psicológicos frequentemente fazem referência a processos que não são diretamente observáveis (processos latentes). Tradicionalmente, no entanto, a investigação desses fenômenos é feita de forma indireta aos processos latentes. O objetivo deste artigo é introduzir os conceitos fundamentais de modelagem multinomial. Aqui mostramos como modelos de processos latentes são derivados de modelos puramente descritivos através da redução do espaço de parâmetros motivada por uma ou mais teorias psicológicas. Os resultados são os modelos multinomiais que fornecem medidas simples de processos psicológicos (probabilidades) e que podem ser quantitativamente testados com dados reais. O uso de modelagem multinomial permite a análise direta dos efeitos de variáveis independentes nos próprios processos latentes que controlam o desempenho em uma ou mais tarefas experimentais, assim, facilitando o teste de predições e explicações teóricas sobre fenômenos psicológicos.

Theories about psychological phenomena often refer to unobservable processes (latent processes). Traditionally, however, the psychological investigation of these phenomena is done indirectly to the latent processes themselves. The objective of this article is to introduce fundamental concepts about multinomial modeling. Here we show that latent processes models are derived from purely descriptive models by reducing the parameter space according to one or more psychological theories. The result is multinomial models that deliver simple measures of psychological processes (probabilities) and that can be tested quantitatively with real data. The use of multinomial modeling allows direct analysis of the effects of independent variables on the latent processes that control performance on one or more experimental tasks, thus making it easier to test theoretical predictions and explanations about psychological phenomena.

Teorías sobre fenómenos psicológicos a menudo se refieren a procesos que no son directamente observables (procesos latentes). Sin embargo, la investigación de estos fenómenos se realiza tradicionalmente de manera indirecta con respecto a los procesos latentes. El propósito de este artículo es presentar los conceptos fundamentales del modelado multinomial. Aquí mostramos cómo los modelos de procesos latentes se derivan de modelos puramente descriptivos al reducir el espacio de parámetros motivado por una o más teorías psicológicas. El resultado son modelos multinomiales que proporcionan medidas simples de procesos psicológicos (probabilidades) y que pueden probarse cuantitativamente con datos reales. El uso de modelos multinomiales permite el análisis directo de los efectos de variables independientes en los procesos latentes que controlan el rendimiento en una o más tareas experimentales, lo que facilita la prueba de predicciones y explicaciones teóricas sobre fenómenos psicológicos.

Randomized response surface pathway design with skewed starting point and stochastic dose window

Background:The aim was to introduce response surface pathway(RSP)-design with skewed starting value and stochastic dose-window to estimate optimal efficacy dose (OED) of BP-C2 after IL-1? stimulation in Atlantic salmon.Methods:54 healthy smolt of Atlantic salmon between 50 and 100g before habituated to saltwater were included. The study was conducted as a one-dimensional, randomized between-patient three-level RSP designed trial with one interventional-and one response variable and odd outcomes. The interventional variable was intraperitoneal injected BPC2 with skewed starting dose of 0.10 mg/100g related to the initial dose-window <0.02-0.5 mg/100g. The response variable was the Ct-value of mRNA IL-1? expression 24 hours after injection.Results:Skewed starting value of 0.10 mg/100g was chosen in the first design-level with a dose-window of <0.0-0.20].The three smolt obtained a reduction in Ct-value above 15%, and the dose-window adjusted with the lower boundary equals the previous dose. The five smolt at second esign-level received 0.16 mg/100g with a dose-window [0.10-0.22]. Four smolt obtained above 15% and one of 0.5% reduction in cycle threshold (Ct)-value. Six smolt in the third design-level received 0.21 mg/100g and one 0.16 mg/100g. The mean Ct-value was reduced from 30.0 in the nstimulated situation to 25.0, 24.8 and 26.4 after BP-C2 stimulation of 0.10, 0.16 and 0.21mg/100g, respectively. The OED of BP-C2 related to IL-1? was estimated to 0.14 mg/100g.Conclusions: Skewed starting value in the initial dose-window made the K-adjustment factor and dose-window stochastic. The RSP-procedure works in accordance to the expectation and estimated OED of BP-C2 sufficiently.

Economic analysis of the risk of replacing corn grains (Zea mays) with pearl millet grains (Pennisetum glaucum) in the diet of feedlot cattle / Análise econômica do risco da substituição de grãos de milho (Zea mays) por grãos de milheto (Pennisetum glaucum) na dieta de bovinos confinados

ABSTRACT: The goal of the present study was to assess the economic viability relating to the risk of replacing corn with pearl millet in diets with 80% concentration for feedlot cattle confined for 89 days. Replacement levels were: 0, 33, 66, and 100%. The risk was estimated using Monte Carlo simulation, Spearman's rank correlation test between input variables, stochastic dominance, and analysis of sensitivity. The expected average values ± standard deviation for net present value (R$/animal) were ± 71.74 ± 283.32, 91.23 ± 285.18, 196.05 ± 273.79, and 223.80 ± 267.96 for diets containing 0, 33, 66, and 100% of pearl millet, respectively. The probability of ≥0 net present value was 63.4, 66.1, 78.4, and 82.4%, respectively. The net present values were statistically different (P<0.05), and the higher levels dominated the lower values. The items that most influenced the net present values were, in descending order, prices of unfinished and finished cattle, initial and final weights, prices of concentrate and forage, concentrate and forage consumption. Based on the results of the simulation, diet of 100% pearl millet exhibited the best economic viability.

RESUMO: O objetivo do estudo foi avaliar a viabilidade econômica relacionada ao risco da substituição de milho por milheto em dietas com 80% de concentrado no confinamento de bovinos por 89 dias. Os níveis de substituição foram: 0, 33, 66 e 100%. O risco foi estimado usando simulação de Monte Carlo, correlação de Spearman entre as variáveis ​​de entrada, dominância estocástica e análise de sensibilidade. Os valores médios esperados ± desvio padrão para o valor presente líquido (R$/animal) foram de ± 71,74 ± 283,32, 91,23 ± 285,18, 196,05 ± 273,79 e 223,80 ± 267,96 para dietas contendo 0, 33, 66 e 100% de milheto, respectivamente. A probabilidade de valor presente líquido ≥0 foi de 63,4, 66,1, 78,4 e 82,4%, respectivamente. Os valores presentes líquidos foram estatisticamente diferentes (p<0,05), e os níveis mais elevados dominaram os valores mais baixos. Os itens que mais influenciaram os valores presentes líquidos foram, em ordem decrescente, os preços de bovinos não terminados e acabados, pesos inicial e final, preços de concentrado e forragem, consumo de concentrado e forragem. Com base nos resultados da simulação, a dieta de 100% de milheto mostrou a melhor viabilidade econômica.

Modeling of lactose enzymatic hydrolysis using Monte Carlo method

Background: Mathematical modeling is useful in the analysis, prediction, and optimization of an enzymatic process. Unlike the conventional modeling methods, Monte Carlo method has special advantages in providing representations of the molecule's spatial distribution. However, thus far, Monte Carlo modeling of enzymatic system is namely based on unimolecular basis, not suitable for practical applications. In this research, Monte Carlo modeling is performed for enzymatic hydrolysis of lactose for the purpose of real-time applications. Results: The enzyme hydrolysis of lactose, which is conformed to Michaelis­Menten kinetics, is modeled using the Monte Carlo modeling method, and the simulation results prove that the model predicts the reaction kinetics very well. Conclusions: Monte Carlo modeling method can be used to model enzymatic reactions in a simple way for real-time applications.

Analysis of the scientific research efficiency of hospital department based on stochastic frontier method / 中华医学科研管理杂志

Objective Based on the data of scientific research output in a top three hospital in Beijing from 2015 and 2016,stochastic frontier analysis is conducted to estimate the efficiency of scientific research performance in different departments of this hospital,so as to draw the impetus for the growth of departments.Methods According to the results of the stochastic frontier model,comprehensive analysis and evaluation are conducted for the research performance of various departments.Results The overall average technical efficiency of the hospital is 0.44,and improvement space for the technical efficiency of scientific research performance is still 0.56.There are significant differences in the technical efficiency of each department.Among the four major categories,the D section is higher than the technical efficiency of class A,B and C departments.Conclusions The overall technical efficiency of the hospital is not high,the level of scientific research output of the four types of departments is not balanced,which should be emphasized in the improvement of scientific research performance level.

Economical operating and technical efficiency of provincial hospitals in Zhejiang: based on Stochastic frontier analysis / 中华医院管理杂志

Objective To analyze the economical operation and technical efficiency of Zhejiang provincial hospitals, and give references for deepening public hospitals reform.Methods We compiled data from 17 provincial public hospitals from 2013 to 2017 in Zhejiang, then used descriptive analysis to study hospitals′operating performance, and used stochastic frontier analysis( SFA) to analyze hospitals′ technical efficiency.Results From 2013 to 2017, the 17 provincial hospitals′ annual growth rate of outpatients and discharges were 5.2% and 9.5% , the number of outpatients and discharges at the general hospitals were 1.8 times and 2.5 times of those in specialized hospitals respectively.In these hospitals, service efficiency had been improved, and the income structure had become more reasonable.However, internal and external factors of the hospitals lowered technical inefficiency in their economic operation. Conclusions The economic operation mechanism of provincial hospitals should be further strengthened, and their external environment be improved as well.Only in this way can the hospitals achieve their operational goal of " doing the right thing and in the right way".

General Linear Models for Pain Prediction in Knee Osteoarthritis: Data from the Osteoarthritis Initiative / Modelos Lineales Generales para Predecir Dolor en Osteoartritis de Rodilla: Datos de la "Osteoarthritis Initiative"

Abstract: Knee pain is the most common and disabling symptom in Osteoarthritis (OA). Joint pain is a late manifestation of the OA. In earlier stages of the disease changes in joint structures are shown. Also, formation of bony osteophytes, cartilage degradation, and joint space reduction which are some of the most common, among others. The main goal of this study is to associate radiological features with the joint pain symptom. Univariate and multivariate studies were performed using Bioinformatics tools to determine the relationship of future pain with early radiological evidence of the disease. All data was retrieved from the Osteoarthritis Initiative repository (OAI). A case-control study was done using available data from participants in OAI database. Radiological data was assessed with different OAI radiology groups. We have used quantitative and semi-quantitative scores to measure two different relations between radiological data in three different time points. The goal was to track the appearance and prevalence of pain as a symptom. All predictive models were statistically significant (P ≤ 0,05), obtaining the receiving operating characteristic (ROC) curves with their respective area under the curves (AUC) of 0.6516, 0.6174, and 0.6737 for T-0, T-1 and T-2 in quantitative analysis. For semi-quantitative an AU C of 0.6865, 0.6486, and 0.6406 for T-0, T-1 and T-2. The models obtained in the Bioinformatics study suggest that early joint structure changes can be associated with future joint pain. An image-based biomarker that could predict future pain, measured in early OA stages, could become a useful tool to improve the quality of life of people dealing OA.

Resumen: El dolor de rodilla es el síntoma más común y limitante de la Osteoartritis (OA), además de presentarse como una manifestación tardía de la enfermedad. Los cambios que ocurren en las estructuras de las articulaciones se presentan en las primeras etapas de la OA. Algunos de los cambios más comunes son la formación de osteofitos óseos, degradación del cartílago, y la reducción del espacio en la articulación, entre otros. El principal objetivo de este estudio es la asociación de características radiológicas con el síntoma de dolor de las articulaciones, para lo que fueron realizados dos estudios: univariado y multivariado, usando herramientas bioinformáticas para determinar la relación de futuro dolor con la evidencia radiológica temprana de la enfermedad. Todos los datos fueron recuperados de la Osteoarthritis Initiative repository (OAI). Este estudio de caso-control se llevó a cabo utilizando los datos disponibles de los participantes de la base de datos de la OAI. Los datos radiológicos fueron evaluados con diferentes grupos de radiología de la OAI. Fueron usadas puntuaciones cuantitativas y semi- cuantitativas para medir las dos diferentes relaciones entre los datos radiológicos en tres diferentes puntos de tiempo. El objetivo fue seguir la trayectoria de la aparición y prevalencia del dolor como síntoma. Todos los modelos predictivos fueron estadísticamente significativos (P ≤ 0,05). Para el análisis cuantitativo se calcularon las áreas bajo la curva (AUC): 0.6516, 0.6174, y 0.6737 para T-0, T-1 y T-2, y para el análisis semi-cuantitativo se calcularon las AU C: 0.6865, 0.6486, y 0.6406 para T-0, T-1 y T-2. Los modelos obtenidos en el estudio bioinformático sugieren que los cambios tempranos en la estructura de las articulaciones pueden estar asociados con el futuro dolor de rodilla. Un biomarcador basado en imágenes que pueda predecir el futuro dolor, medido en las primeras etapas de OA, podría convertirse en una herramienta útil para mejorar la calidad de vida de la gente que padece OA.

Research on DNA mixture de-convolution with stochastic simulation method / 中国法医学杂志

Objective To analyze a large number of DNA mixture de-convolution data with stochastic simulation method. Methods Using the software in Identifiler, PP18D, AGCU EX20, PP21, AGCU EX20 & AGCU 21+1 system, 1 million groups of STR genotyping of mixture were analyzed. The average de-convoluted loci (L), the average de-convoluted combinatorial number (Π) were counted out. Results In identifiler, PP18D, AGCU EX20, PP21, AGCU EX20 & AGCU 21+1 system, L were 4.8, 5.8, 6.7, 7.0, 11.1, and Π were 3.71×104, 1.06×105, 3.34×105, 6.40×105, 2.48×1012. Conclusion The result in this paper has some guiding significance in DNA mixture de-convolution followed by DNA Database search.

Resting State Effective Connectivity between Inferior Parietal Lobe (IPL) and Inferior Temporal Gyrus (ITG) in the Left and Right Hemispheres / Jurnal Sains Kesihatan Malaysia

Inferior parietal lobule (IPL) and inferior temporal gyrus (ITG) are two important brain regions for the default modenetwork (DMN). IPL has been known to be involved in the control of attention and responding to given information whileITG is involved in the processing and perception awakened by visual stimuli. These two key DMN regions are highlyinterconnected as determined from white matter and fiber tracking studies. However, little is known about their natureof connectivity while the brain is at rest, whether it is linear, bilinear or nonlinear and whether it is of mono- or bidirection.Resting state functional magnetic resonance imaging (rsfMRI) data were obtained from 7 healthy male andfemale participants (average age = 20.7 ± 4.5 years) and were concatenated. Data were analyzed using statisticalparametric mapping (SPM12). Endogenous brain signals were modelled by Fourier series at 0.01 – 0.08 Hz. IPL-ITGconnected linear, bilinear and non-linear causal models in both hemispheres were constructed and estimated by means ofstochastic dynamic causal modelling (sDCM) and were compared using Bayesian Model Selection (BMS) for group studies.Group fixed-effects results indicated that bilateral IPL and ITG exhibited high neural activity at a corrected significantlevel (pFWE 1000) which has the best balance betweenmodel accuracy and difficulty. The minimum free energy (F) = -4.41 × 104 and -4.09 × 104 for left and right hemispherebilinear models respectively. From BMS and DCM results, it was found that IPL and ITG do have a dynamic collaborationbetween each other, a connectivity that belongs to a greater network when the brain is at rest. The intrinsic connectionsbetween them are negative in both directions i.e. IPL and ITG mutually inhibited each other. The effective connectivitywas modulated by the endogenous fluctuation of the brain signal.

Automatic clustering method of flow cytometry data based on -distributed stochastic neighbor embedding / 生物医学工程学杂志

The traditional method of multi-parameter flow data clustering in flow cytometry is to mainly use professional software to manually set the door and circle out the target cells for analysis. The analysis process is complex and professional. Based on this, a clustering algorithm, which is based on -distributed stochastic neighbor embedding ( -SNE) algorithm for multi-parameter stream data, is proposed in the paper. In this algorithm, the Euclidean distance of sample data in high dimensional space is transformed into conditional probability to represent similarity, and the data is reduced to low dimensional space. In this paper, the stained human peripheral blood cells were treated by flow cytometry, and the processed data were derived as experimental sample data. The -SNE algorithm is compared with the kernel principal component analysis (KPCA) dimensionality reduction algorithm, and the main component data obtained by the dimensionality reduction are classified using -means algorithm. The results show that the -SNE algorithm has a good clustering effect on the cell population with asymmetric and trailing distribution, and the clustering accuracy can reach 92.55%, which may be helpful for automatic analysis of multi-color multi-parameter flow data.

Lessons and perspectives for applications of stochastic models in biological and cancer research

The effects of randomness, an unavoidable feature of intracellular environments, are observed at higher hierarchical levels of living matter organization, such as cells, tissues, and organisms. Additionally, the many compounds interacting as a well-orchestrated network of reactions increase the difficulties of assessing these systems using only experiments. This limitation indicates that elucidation of the dynamics of biological systems is a complex task that will benefit from the establishment of principles to help describe, categorize, and predict the behavior of these systems. The theoretical machinery already available, or ones to be discovered to help solve biological problems, might play an important role in these processes. Here, we demonstrate the application of theoretical tools by discussing some biological problems that we have approached mathematically: fluctuations in gene expression and cell proliferation in the context of loss of contact inhibition. We discuss the methods that have been employed to provide the reader with a biologically motivated phenomenological perspective of the use of theoretical methods. Finally, we end this review with a discussion of new research perspectives motivated by our results.

Cadenas de markov aplicadas al análisis de la ejecución de proyectos de investigación / Markov chains applied to the analyzis of the progress of research projets

La administración moderna requiere el apoyo de herramientas de diferentes ramas de la ciencia que ayuden al proceso de toma de decisiones, como por ejemplo la Matemática Aplicada. En este contexto aparecen variables aleatorias que con el transcurso del tiempo cambian, y que pueden ser representadas a través de modelos cuantitativos. Cuando en estos modelos el estado presente de dichas variables resume toda la información anterior para describir cómo se comportarán en el futuro, se dice que se está en presencia de una cadena de Markov; una herramienta eficiente para el análisis de procesos de esta naturaleza, como por ejemplo la ejecución de proyectos de investigación, el cual reviste gran importancia en la gestión de ciencia e innovación tecnológica; área de resultados clave en cualquier universidad. En la Facultad de Tecnología de la Universidad de Ciencias Médicas de Santiago de Cuba, el análisis de la ejecución de los proyectos de investigación se consideró como una cadena de Markov, definiendo los diferentes estados por los que puede estar un proyecto, y las probabilidades de que este se encuentre en un estado determinado a partir del estado en que se encontraba. Así se determinaron elementos que permiten apoyar la toma de decisiones a corto y a largo plazo, a partir de datos históricos durante el trienio 2013 - 2015, relacionados con la cantidad promedio de inspecciones a los mismos, probabilidades de un proyecto cerrar, etc.; permitiendo pronosticar en términos de probabilidades el estado de este subsistema en el futuro(AU)

Modern management tools require support from different branches of science to help the decision-making process, such as Applied Mathematics. In this context, random variables with change over time, and that can be represented by quantitative models appear. When these models in the present state of these variables summarizes all the previous information to describe how they will behave in the future, it is said that we are in the presence of a Markov chain; an efficient tool for the analysis of processes of this nature, such as the execution of research projects, which is of great importance in the management of science and technological innovation; key result area at any university. In the Faculty of Technology, University of Medical Sciences of Santiago de Cuba, the analysis of the implementation of research projects was considered as a Markov chain, defining the different states through which can be a project and the odds of this is in a certain state from the state it was. And support elements that enable decision-making in the short and long term, from historical data in the period 2013 - 2015 were determined, related to the average number of inspections to a project, the probability of a project likely to close, etc.; allowing to predict in terms of probabilities the status of this subsystem in the future(AU)