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1.
J Radiol Prot ; 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940166

RESUMO

The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for paediatric interventional cardiology procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study is conducted in the framework of the OPRIPALC programme coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the programme was focused on paediatric interventional cardiology. Dose data from diagnostic and therapeutic procedures were collected between December 2020 and December 2021. Regional DRLs have been set as the 3rd quartile of patient dose data (kerma area-product) collected in 18 hospitals from 10 countries in an initial sample of 968 procedures. DRLs have been set for four age bands and five weight ranges. The values obtained for the four age bands (<1 year, 1 to <5 years, 5 to <10 years and 10 to <16 years) have been 2.9; 6.1; 8.8 and 14.4 Gy.cm2 for diagnostic procedures, and 4.0, 5.0, 10.0 and 38.1 Gy.cm2 for therapeutic procedures, respectively. The values obtained for the five weight bands (<5 kg, 5 to <15 kg, 15 to <30 kg, 30 to <50 kg and 50 to <80 kg) have been 3.0, 4.5, 8.1, 9.2 and 26.8 Gy.cm2 for diagnostic procedures and 3.7, 4,3, 7.3, 16.1 and 53.4 Gy.cm2 for therapeutic procedures, respectively. While initial data were collected manually as patient dose management systems were not available in most of the hospitals involved in the programme, a centralized automatic dose management system for the collection and management of patient dose indicators has now been introduced and is envisaged to increase the sample size. The possibility of alerting on high dose values and introducing corrective actions will help in optimization.

2.
J Chem Phys ; 156(23): 234106, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35732515

RESUMO

Dispersion interactions are one of the components of van der Waals (vdW) forces that play a key role in the understanding of intermolecular interactions in many physical, chemical, and biological processes. The theory of dispersion forces was developed by London in the early years of quantum mechanics. However, it was only in the 1960s that it was recognized that for molecules lacking an inversion center, such as chiral and helical molecules, there are chirality-sensitive corrections to the dispersion forces proportional to the rotatory power known from the theory of circular dichroism and with the same distance scaling law R-6 as the London energy. The discovery of the chirality-induced spin selectivity effect in recent years has led to an additional twist in the study of chiral molecular systems, showing a close relation between spin and molecular geometry. Motivated by it, we propose in this investigation to describe the mutual induction of charge and spin-density fluctuations in a pair A-B of chiral molecules by a simple physical model. The model assumes that the same fluctuating electric fields responsible for vdW forces can induce a magnetic response via a Rashba-like term so that a spin-orbit field acting on molecule B is generated by the electric field arising from charge density fluctuations in molecule A (and vice versa). Within a second-order perturbative approach, these contributions manifest as an effective intermolecular exchange interaction. Although expected to be weaker than the standard London forces, these interactions display the same R-6 distance scaling.


Assuntos
Teoria Quântica , Londres , Estereoisomerismo
3.
Data Brief ; 42: 108095, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35402665

RESUMO

Energy and power system models have become necessary tools that provide challenges and technical and economic solutions for integrating high shares of Variable Renewable Energy. Models are focused on analysing strategies of power systems to achieve their decarbonisation targets. The data presented in this paper includes the model algorithm, inputs, equations, modelling assumptions, supplementary materials, and results of the simulations supporting the research article titled "Facing the high share of variable renewable energy in the power system: flexibility and stability requirements". The analysis is based on data from the system operator of one of the European Union member states (Spain). The developed model allows making projections and calculations to obtain the power generation of each technology, the international interconnections, inertia, emissions, system costs and flexibility requirements of new technologies. These data can be used for energy policy development or decision making on power capacity and the balancing needs of the future power system.

4.
PLoS One ; 17(3): e0265175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35298506

RESUMO

Accessibility of multispectral, multitemporal imagery combined with recent advances in cloud computing and machine learning approaches have enhanced our ability to model habitat characteristics across broad spatial and temporal scales. We integrated a large dataset of known nest and roost sites of a threatened species, the Mexican spotted owl (Strix occidentalis lucida), in the southwestern USA with Landsat imagery processed using the Continuous Change Detection and Classification (CCDC) time series algorithm on Google Earth Engine. We then used maximum entropy modeling (Maxent) to classify the landscape into four 'spectral similarity' classes that reflected the degree to which 30-m pixels contained a multispectral signature similar to that found at known owl nest/roost sites and mapped spectral similarity classes from 1986-2020. For map interpretation, we used nationally consistent forest inventory data to evaluate the structural and compositional characteristics of each spectral similarity class. We found a monotonic increase of structural characteristics typically associated with owl nesting and roosting over classes of increasing similarity, with the 'very similar' class meeting or exceeding published minimum desired management conditions for owl nesting and roosting. We also found an increased rate of loss of forest vegetation typical of owl nesting and roosting since the beginning of the 21st century that can be partly attributed to increased frequency and extent of large (≥400 ha) wildfires. This loss resulted in a 38% reduction over the 35-year study period in forest vegetation most similar to that used for owl nesting and roosting. Our modelling approach using cloud computing with time series of Landsat imagery provided a cost-effective tool for landscape-scale, multidecadal monitoring of vegetative components of a threatened species' habitat. Our approach could be used to monitor trends in the vegetation favored by any other species, provided that high-quality location data such as we presented here are available.


Assuntos
Espécies em Perigo de Extinção , Estrigiformes , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Florestas
5.
Nanotechnology ; 33(17)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35026738

RESUMO

On Cu(111) surface and in interaction with a single hexa-tert-butylphenylbenzene molecule-gear, the rotation of a graphene nanodisk was studied using the large-scale atomic/molecular massively parallel simulator molecular dynamics simulator. To ensure a transmission of rotation to the molecule-gear, the graphene nanodisk is functionalized on its circumference bytert-butylphenyl chemical groups. The rotational motion can be categorized underdriving, driving and overdriving regimes calculating the locking coefficient of this mechanical machinery as a function of external torque applied to the nanodisk. The rotational friction with the surface of both the phononic and electronic contributions is investigated. For small size graphene nanodisks, the phononic friction is the main contribution. Electronic friction dominates for the larger disks putting constrains on the experimental way of achieving the transfer of rotation from a graphene nanodisk to a single molecule-gear.

6.
Semergen ; 48(1): 14-22, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34479795

RESUMO

OBJECTIVES: To assess users' attitudes and knowledge of users about how and where inhalers are removed after finalizing their use, and to describe their opinion about utilizing re-usable inhalers. METHODS: Cross-sectional, multi-center, and opinion survey, conducted to assess behavior and attitudes regarding the disposal of inhalers recycling and the use of re-usable inhalers, through the application of an ad hoc questionnaire about the knowledge and attitudes, with data about the use and recycling of inhalers. RESULTS: A total of 303 subjects (57.5±19.9 years; time of inhalers' use 9.6±9.8 years; asthma/COPD: 46.2%/25.7%) were included. Pressurized metered-dose inhalers were the most commonly used inhalers (30.5%). Most users considered the recycling of inhalers to be very important (7.75±2.76, out of 10), and rated highly the availability of having a monthly rechargeable inhaler every 6 months (7.77±2.79, out of 10). Only 33% of users had been informed by their healthcare professionals about the place of delivering the inhaler. With respect to recycling, 42.9% of all users recycled in the SIGRE point of the pharmacy. Regarding the final destination of inhalers, 43.6% thought that the removed inhalers were recycled or destroyed, but 35.3% did not know what would happen to the inhalers after placing in the SIGRE point. CONCLUSIONS: Despite users considered the importance of inhalers recycling and the availability of re-usable inhalers, a significant proportion does not recycle in the SIGRE point, has not been informed about the appropriate place of delivering the inhaler and ignores what happens to inhalers. Information campaigns are warranted.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Administração por Inalação , Asma/tratamento farmacológico , Estudos Transversais , Humanos , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
7.
Results Phys ; : 104845, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34603944

RESUMO

This study was conducted to predict the number of COVID-19 cases, deaths and recoveries using reported data by the Algerian Ministry of health from February 25, 2020 to January 10, 2021. Four models were compared including Gompertz model, logistic model, Bertalanffy model and inverse artificial neural network (ANNi). Results showed that all the models showed a good fit between the predicted and the real data (R2>0.97). In this study, we demonstrate that obtaining a good fit of real data is not directly related to a good prediction efficiency with future data. In predicting cases, the logistic model obtained the best precision with an error of 0.92% compared to the rest of the models studied. In deaths, the Gompertz model stood out with a minimum error of 1.14%. Finally, the ANNi model reached an error of 1.16% in the prediction of recovered cases in Algeria. .

8.
J Commun Disord ; 92: 106113, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34098333

RESUMO

The production of facial expressions is an important skill that allows children to share and adapt emotions during social interactions. While deaf children are reported to show delays in their social and emotion understanding, the way in which they produce facial expressions of emotions has been relatively unexplored. The present study investigated the production of facial expressions of emotions by young congenitally deaf children. Six facial expressions of emotions produced by 5 congenitally deaf children and 5 hearing children (control group) were filmed across three tasks: 1) voluntarily posed expression of emotion 2) responding to social stories 3) intentionally mimicking expressions of emotion. The recorded videos were analysed using a software based of the Facial Action Coding System (FACS), and then judged by adult raters using two different scales: according to the emotion elicited (i.e. accuracy) and the intensity of the emotion produced. The results of both measurement scales showed that all children (deaf and hearing) were able to produce socially recognisable prototypical configuration of facial expressions. However, the deaf children were rated by adults as expressing their emotions with greater intensity compared to the hearing children. The results suggest deaf children may show more exaggerated facial expressions of emotion, possibly to avoid any ambiguity in communication.


Assuntos
Emoções , Expressão Facial , Adulto , Criança , Comunicação , Audição , Humanos , Gravação de Videoteipe
9.
Nonlinear Dyn ; 104(4): 4655-4669, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967393

RESUMO

The present work is focused on modeling and predicting the cumulative number of deaths from COVID-19 in México by comparing an artificial neural network (ANN) with a Gompertz model applying multiple optimization algorithms for the estimation of coefficients and parameters, respectively. For the modeling process, the data published by the daily technical report COVID-19 in Mexico from March 19th to September 30th were used. The data published in the month of October were included to carry out the prediction. The results show a satisfactory comparison between the real data and those obtained by both models with a R2 > 0.999. The Levenberg-Marquardt and BFGS quasi-Newton optimization algorithm were favorable for fitting the coefficients during learning in the ANN model due to their fast and precision, respectively. On the other hand, the Nelder-Mead simplex algorithm fitted the parameters of the Gompertz model faster by minimizing the sum of squares. Therefore, the ANN model better fits the real data using ten coefficients. However, the Gompertz model using three parameters converges in less computational time. In the prediction, the inverse ANN model was solved by a genetic algorithm obtaining the best precision with a maximum error of 2.22% per day, as opposed to the 5.48% of the Gompertz model with respect to the real data reported from November 1st to 15th. Finally, according to the coefficients and parameters obtained from both models with recent data, a total of 109,724 cumulative deaths for the inverse ANN model and 100,482 cumulative deaths for the Gompertz model were predicted for the end of 2020.

10.
Diabetes Res Clin Pract ; 173: 108692, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33571599

RESUMO

AIM: To determine the percentages of (CD19 + CD24 + CD38+, CD19 + CD24 + CD27+, CD19 + IL-10+)-Breg cells, IL-17 single and IL-17+/IFN-γ double producers T cells and IFN-γ+ T cells, in normal-glycemic individuals, prediabetes and T2DM patients, and to analyze the association of Breg cells with metabolic parameters of T2DM. METHODS: percentages of Breg cells, IL-17+ and IL-17 + IFN-γ+ T cells, IFN-γ+ T cells and IL-10 were determined by flow cytometry. IL-6 levels were evaluated by ELISA assay. RESULTS: increased IL-6 levels, IL-17+ and IL-17 + IFN-γ+ T cells and a diminution of IL-10 levels and CD19 + IL-10+ cells in T2DM patients were observed. We found that CD19 + CD24 + CD27+ cells and CD19 + CD24 + CD38+ cells were increased in T2DM patients. The percentages of CD19 + CD24 + CD38+ cells were associated with HOMA-B, TyG index, HDL and cholesterol values. In normal-glycemic individuals, CD19 + CD24 + CD27+ cells were inversely associated to triglycerides and TyG index. In prediabetes patients, CD19 + CD24 + CD38+ cells were inversely related with cholesterol and LDL. Finally, CD19 + CD24 + CD38+ cells were inversely related with HDL values in T2DM patients. CONCLUSION: Our results suggest that increased percentages of IL-17 single and IL-17/IFN-γ double producers T cells in T2DM patients may be a consequence of the initial CD19 + IL-10+ cells reduction. Furthermore, dyslipidemia could play an important role in percentages and activity of B regulatory cells.


Assuntos
Linfócitos B Reguladores/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inflamação/metabolismo , Estado Pré-Diabético/metabolismo , Adulto , Feminino , Humanos , Masculino
11.
Conserv Biol ; 35(1): 336-345, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32297668

RESUMO

Recent bioacoustic advances have facilitated large-scale population monitoring for acoustically active species. Animal sounds, however, can of information that is underutilized in typical approaches to passive acoustic monitoring (PAM) that treat sounds simply as detections. We developed 3 methods of extracting additional ecological detail from acoustic data that are applicable to a broad range of acoustically active species. We conducted landscape-scale passive acoustic surveys of a declining owl species and an invasive congeneric competitor in California. We then used sex-specific vocalization frequency to inform multistate occupancy models; call rates at occupied sites to characterize interactions with interspecific competitors and assess habitat quality; and a flexible multivariate approach to differentiate individuals based on vocal characteristics. The multistate occupancy models yielded novel estimates of breeding status occupancy rates that were more robust to false detections and captured known habitat associations more consistently than single-state occupancy models agnostic to sex. Call rate was related to the presence of a competitor but not habitat quality and thus could constitute a useful behavioral metric for interactions that are challenging to detect in an occupancy framework. Quantifying multivariate distance between groups of vocalizations provided a novel quantitative means of discriminating individuals with ≥20 vocalizations and a flexible tool for balancing type I and II errors. Therefore, it appears possible to estimate site turnover and demographic rates, rather than just occupancy metrics, in PAM programs. Our methods can be applied individually or in concert and are likely generalizable to many acoustically active species. As such, they are opportunities to improve inferences from PAM data and thus benefit conservation.


Uso de la Importancia Ecológica de las Vocalizaciones Animales para Mejorar la Inferencia en los Programas de Monitoreo Acústico Resumen Los avances bioacústicos recientes han facilitado el monitoreo a gran escala de poblaciones de especies acústicamente activas. Sin embargo, los sonidos de animales pueden transmitir cantidades sustanciales de información que queda utilizada insuficientemente en las estrategias comunes de monitoreo acústico pasivo (MAP) que tratan a los sonidos como simples detecciones. Desarrollamos tres métodos de extracción de detalles ecológicos adicionales de los datos acústicos que son aplicables a una gama amplia de especies acústicamente activas. Realizamos censos acústicos pasivos a escala de paisaje para una especie de búho en declinación y para un competidor congenérico invasivo en California. Después utilizamos la frecuencia de vocalizaciones específicas por sexo para orientar los modelos multiestado de ocupación; las tasas de llamados en sitios ocupados para caracterizar las interacciones con los competidores interespecíficos y evaluar la calidad de su hábitat; y una estrategia multivariada flexible para diferenciar a los individuos con base en sus características vocales. Los modelos multiestado de ocupación brindaron estimaciones novedosas para las tasas de ocupación por estado reproductivo que fueron más sólidas ante las detecciones falsas y capturaron el número de asociaciones de hábitat más sistemáticamente que los modelos de estado único agnósticos al sexo. La tasa de llamados estuvo relacionada con la presencia de un competidor pero no con la calidad del hábitat y por lo tanto podría constituir una medida conductual útil para las interacciones que son difíciles de detectar en un marco de trabajo de ocupación. La cuantificación de la distancia multivariada entre los grupos de vocalizaciones proporcionó un medio cuantitativo novedoso para discriminar a los individuos con ≥20 vocalizaciones y una herramienta flexible para balancear los errores del tipo I y del tipo II. Por lo tanto, parecer que hay posibilidad de estimar las tasas demográficas y de rotación, en lugar de sólo las medidas de ocupación, en los programas MAP. Nuestros métodos pueden aplicarse individualmente o de manera conjunta y es probable poder generalizarlas para muchas especies acústicamente activas. Dicho así, son oportunidades para mejorar las inferencias de los datos MAP y por lo tanto, beneficiar a la conservación.


Assuntos
Conservação dos Recursos Naturais , Vocalização Animal , Acústica , Animais , Ecossistema
12.
J Agromedicine ; 26(2): 211-219, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33143555

RESUMO

Occupational and environmental exposures in the agricultural industry have been associated with several illnesses and poor health outcomes. Information regarding the characteristics and health status of the labor force working in the agricultural sector in Puerto Rico is limited. The overall objective of this study was to increase the available information on agricultural workers health and needs by ascertaining the potential differences in characteristics and health status of farmworkers when compared to the general population in rural Puerto Rico This cross-sectional study used the collection and analysis of medical records of agricultural workers and non-agricultural workers in Hospital General Castañer, located in Lares, Puerto Rico. The research period was five years, from 2012 to 2016. This research described agricultural workers' demographic and socioeconomic profile and evaluated relationships between one or more demographic variables and farmer's health. Agricultural workers presented alower prevalence of hypertensive disease (69.4%) and ahigher prevalence of cerebrovascular disease (3.4%) when compared to non-agricultural workers. In other words, agricultural workers were 21% less likely to have hypertensive disease as compared to non-agricultural workers. Results for agricultural workers showed that 4.0% of the workers were diagnosed with arthritis, and 48.8% had suffered at least one type of dorsopathy. The results from this research provide useful information for developing an appropriate framework to address Puerto Rican agricultural worker's health while promoting the agricultural industry development on the island. Finally, this study provided insight into the prevalence and demographic characteristics of agriculture workers in acentral region of Puerto Rico. Further efforts are needed to better define the agricultural workers and farming communities in Puerto Rico that may be exposed to related hazards.


Assuntos
Emprego , Fazendeiros , Doença Crônica , Estudos Transversais , Humanos , Porto Rico/epidemiologia
13.
Rehabilitacion (Madr) ; 55(4): 320-324, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33168182

RESUMO

We describe the case of a 49-year-old woman who, after surgical treatment of breast cancer, developed axillary web syndrome (AWS) followed, 3 weeks later, by the appearance of soft and painless subcutaneous nodules along the cords and close to the flexure of the elbow. After tests (soft tissue and Doppler ultrasound), a dermal/subcutaneous or neoplastic cause was ruled out, although a cephalic and ulnar venous thrombosis was revealed. Anticoagulant medication was prescribed, with disappearance of the nodules 3-4 weeks later and improvement of AWS. The symptoms, clinical course, diagnostic tests, as well as the published evidence, helped to establish a diagnosis of AWS with subcutaneous nodules. AWS is an early complication after axillary surgery, which is well known among breast cancer professionals and whose diagnosis is based on clinical presentation. Its association with subcutaneous nodules is one of its rare variants and requires compulsory complementary studies to exclude other causes. Like AWS, nodules are believed to be due to lymphatic vessel thrombosis.


Assuntos
Neoplasias da Mama , Axila , Neoplasias da Mama/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Mastectomia , Pessoa de Meia-Idade , Síndrome
14.
Andes Pediatr ; 92(5): 781-789, 2021 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-35319588

RESUMO

In recent decades, the vegetarian dietary option has been increasing in the general population, in cluding the pediatric age group. This has led to numerous questions regarding the benefits and risks that may arise from its implementation. Food restriction implies the potential deficiency of several nutrients, establishing some of them as critical for this period of development and rapid growth, so the safety of vegetarian diets has not been fully established worldwide. The main critical nutrients are iron, zinc, calcium, vitamin B12, and omega-3 fatty acids. The groups most at risk of nutritional deficiencies are infants, adolescents, more restrictive vegetarian options, and those who do not have adequate professional nutritional counseling. Therefore, vegetarian diets should be strictly supervi sed. Scientific societies such as the American, Canadian, Italian, and British nutrition societies recog nize vegetarian diets as healthy in the pediatric age as long as they are supervised by qualified health professionals. However, there are others that do not support it as the French one, while the Spanish one supports it with restrictions in the infant period. The objective of this publication is to describe potential nutritional deficiencies and to provide recommendations to follow a balanced and safe ve getarian diet in the pediatric population according to the available information, paying attention to the limitations that we may have in the implementation of this diet in our population, especially in critical stages such as infants and adolescents.


Assuntos
Dieta Vegetariana , Pediatria , Adolescente , Canadá , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Humanos , Lactente , Necessidades Nutricionais , Estados Unidos
15.
Andes Pediatr ; 92(6): 991, 2021 12.
Artigo em Espanhol | MEDLINE | ID: mdl-35506820
16.
Semergen ; 46(8): 512-523, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-33239152

RESUMO

OBJECTIVE: To describe the quantitative use of inhaled rescue medication in an asthmatic population treated in the Primary Care clinics, and secondly to determine its possible relationship as regards other variables associated with control. MATERIAL AND METHODS: An observational, descriptive study was conducted on a randomised sample of all the asthmatic patients with more than one year of onset, and coming from 17 Primary Care catchment areas. 1 year observation period. The data collected included sociodemographic variables and characteristics of the asthma, such as the use of short-acting beta-agonists (SABA) and level of control as regards its frequency of use, the use of inhaled control medication (ICM), number of hospital exacerbations, smoking habits, and availability of an action plan. The data were obtained from the clinical history and the computerised prescription modules. RESULTS: A total of 442 asthmatic patients were included (59.5% female), with a mean age of 45.4 years. The total number of SABA containers prescribed in one year per patient was between 0 and 25 containers, with a mean of 4.26 (SD=4.1). Only 46.6% showed a regular use of an ICM. The number of SABA containers prescribed to patients with an intermittent use of an ICM was significantly higher than those patients that used it regularly (P=.001). There was an association between the number of exacerbations and the number of SABA containers prescribed (Spearman correlation coefficient=0.474, P<.001), as such that the higher the number of containers prescribed there was also a higher number of hospitalised asthmatic exacerbations. CONCLUSIONS: A considerable number of asthmatics in the sample had elevated prescriptions for SABA inhalers and within the defined quantitative ranges of at least a partially or poor-controlled asthma. There is a positive relationship between the overuse of SABA and the intermittent use of the ICM, the same as with hospital exacerbations, smoking, and the lack of a written action plan..


Assuntos
Asma , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Autoanticorpos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nebulizadores e Vaporizadores , Atenção Primária à Saúde
17.
Phys Rev Lett ; 125(16): 160601, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33124846

RESUMO

Symmetry-breaking dynamical phase transitions (DPTs) abound in the fluctuations of nonequilibrium systems. Here, we show that the spectral features of a particular class of DPTs exhibit the fingerprints of the recently discovered time-crystal phase of matter. Using Doob's transform as a tool, we provide a mechanism to build classical time-crystal generators from the rare event statistics of some driven diffusive systems. An analysis of the Doob's smart field in terms of the order parameter of the transition then leads to the time-crystal lattice gas (TCLG), a model of driven fluid subject to an external packing field, which presents a clear-cut steady-state phase transition to a time-crystalline phase characterized by a matter density wave, which breaks continuous time-translation symmetry and displays rigidity and long-range spatiotemporal order, as required for a time crystal. A hydrodynamic analysis of the TCLG transition uncovers striking similarities, but also key differences, with the Kuramoto synchronization transition. Possible experimental realizations of the TCLG in colloidal fluids are also discussed.

18.
Chaos Solitons Fractals ; 138: 109946, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32836915

RESUMO

This work presents the modeling and prediction of cases of COVID-19 infection in Mexico through mathematical and computational models using only the confirmed cases provided by the daily technical report COVID-19 MEXICO until May 8th. The mathematical models: Gompertz and Logistic, as well as the computational model: Artificial Neural Network were applied to carry out the modeling of the number of cases of COVID-19 infection from February 27th to May 8th. The results show a good fit between the observed data and those obtained by the Gompertz, Logistic and Artificial Neural Networks models with an R2 of 0.9998, 0.9996, 0.9999, respectively. The same mathematical models and inverse Artificial Neural Network were applied to predict the number of cases of COVID-19 infection from May 9th to 16th in order to analyze tendencies and extrapolate the projection until the end of the epidemic. The Gompertz model predicts a total of 47,576 cases, the Logistic model a total of 42,131 cases, and the inverse artificial neural network model a total of 44,245 as of May 16th. Finally, to predict the total number of COVID-19 infected until the end of the epidemic, the Gompertz, Logistic and inverse Artificial Neural Network model were used, predicting 469,917, 59,470 and 70,714 cases, respectively.

19.
Histol Histopathol ; 35(10): 1083-1103, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32329808

RESUMO

Intussusceptive angiogenesis (IA) is currently considered an important alternative and complementary form of sprouting angiogenesis (SA). Conversely, intussusceptive lymphangiogenesis (IL) is in an initial phase of study. We compare their morphofunctional characteristics, since many can be shared by both processes. To that end, the following aspects are considered: A) The concept of IA and IL as the mechanism by which blood and lymphatic vessels split, expand and remodel through transluminal pillar formations (hallmarks of intussusception). B) Terminology and historical background, with particular reference to the group of Burri, including Djonov and Patan, who initiated and developed the vessel intussusceptive concept in blood vessels. C) Incidence in normal (e.g. in the sinuses of developing lymph nodes) and pathologic conditions, above all in vessel diseases, such as dilated veins in hemorrhoidal disease, intravascular papillary endothelial hyperplasia (IPEH), sinusoidal hemangioma, lobular capillary hemangioma, lymphangiomas/lymphatic malformations and vascular transformation of lymph nodes. D) Differences and complementarity between vessel sprouting and intussusception. E) Characteristics of the cover (endothelial cells) and core (connective tissue components) of pillars and requirements for pillar identification. F) Structures involved in pillar formation, including endothelial contacts of opposite vessel walls, interendothelial bridges, merged adjacent capillaries, vessel loops and spilt pillars. G) Structures resulting from pillars with intussusceptive microvascular growth, arborization, remodeling and segmentation (compartmentalization). H) Influence of intussusception in the morphogenesis of vessel tumors/ pseudotumors; and I) Hemodynamic and molecular control of vessel intussusception, including VEGF, PDGF BB, Hypoxia, Notch, Endoglobin and Nitric oxide.


Assuntos
Vasos Sanguíneos/patologia , Linfangiogênese , Vasos Linfáticos/patologia , Neovascularização Patológica , Neovascularização Fisiológica , Proteínas Angiogênicas/metabolismo , Animais , Vasos Sanguíneos/metabolismo , Humanos , Vasos Linfáticos/metabolismo , Transdução de Sinais , Terminologia como Assunto
20.
Gut Microbes ; 12(1): 1732852, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32167011

RESUMO

BACKGROUND: . Oral administration of bovine antibodies active against enterotoxigenic Escherichia coli (ETEC) have demonstrated safety and efficacy against diarrhea in human challenge trials. The efficacy of bovine serum immunoglobulins (BSIgG) against recombinant colonization factor CS6 or whole cell ETEC strain B7A was assessed against challenge with the CS6-expressing B7A. METHODS: . This was a randomized, double-blind, placebo-controlled trial in which healthy adults received oral hyperimmune BSIgG anti-CS6, anti-B7A whole cell killed or non-hyperimmune BSIgG (placebo) in a 1:1:1 ratio then challenged with ETEC B7A. Two days pre-challenge, volunteers began a thrice daily, seven day course of immunoprophylaxis. On day 3, subjects received 1 × 1010 CFUs of B7A. Subjects were observed for safety and the primary endpoint of moderate-severe diarrhea (MSD). RESULTS: . A total of 59 volunteers received product and underwent ETEC challenge. The BSIgG products were well-tolerated across all subjects. Upon challenge, 14/20 (70%) placebo recipients developed MSD, compared to 12/19 (63%; p = .74) receiving anti-CS6 BSIgG and 7/20 (35%; p = .06) receiving anti-B7A BSIgG. Immune responses to the ETEC infection were modest across all groups. CONCLUSIONS: . Bovine-derived serum antibodies appear safe and well tolerated. Antibodies derived from cattle immunized with whole cell B7A provided 50% protection against MSD following B7A challenge; however, no protection was observed in subjects receiving serum antibodies targeting CS6. The lack of observed efficacy in this group may be due to low CS6 surface expression on B7A, the high dose challenge inoculum and/or the use of serum derived antibodies versus colostrum-derived antibodies.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Escherichia coli Enterotoxigênica/imunologia , Infecções por Escherichia coli/tratamento farmacológico , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Adolescente , Adulto , Animais , Anticorpos Antibacterianos/administração & dosagem , Bovinos , Diarreia/tratamento farmacológico , Método Duplo-Cego , Enterotoxinas/imunologia , Feminino , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Profilaxia Pré-Exposição , Adulto Jovem
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