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1.
Sensors (Basel) ; 24(2)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38257503

RESUMEN

It has been proven that structural damage can be successfully identified using trendlines of structural acceleration responses. In previous numerical and experimental studies, the Savitzky-Golay filter and moving average filter were adjusted to determine suitable trendlines and locate structural damage in a simply supported bridge. In this study, the quadratic regression technique was studied and employed to calculate the trendlines of the bridge acceleration responses. The normalized energies of the resulting trendlines were then used as a damage index to identify the location and severity of the structural bridge damage. An ABAQUS model of a 25 m simply supported bridge under a truckload with different velocities was used to verify the accuracy of the proposed method. The structural damage was numerically modeled as cracks at the bottom of the bridge, so the stiffness at the damage positions was decreased accordingly. Four different velocities from 1 m/s to 8 m/s were used. The proposed method can identify structural damage in noisy environments without monitoring the dynamic modal parameters. Moreover, the accuracy of the newly proposed trendline-based method was increased compared to the previous method. For velocities up to 4 m/s, the damage in all single- and multiple-damage scenarios was successfully identified. For the velocity of 8 m/s, the damage in some scenarios was not located accurately. Additionally, it should be noted that the proposed method can be categorized as an online, quick, and baseline-free structural damage-detection method.

2.
BMC Neurol ; 23(1): 309, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608251

RESUMEN

BACKGROUND: This systematic review synthesizes the most recent neuroimaging procedures and machine learning approaches for the prediction of conversion from mild cognitive impairment to Alzheimer's disease dementia. METHODS: We systematically searched PubMed, SCOPUS, and Web of Science databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematic review guidelines. RESULTS: Our search returned 2572 articles, 56 of which met the criteria for inclusion in the final selection. The multimodality framework and deep learning techniques showed potential for predicting the conversion of MCI to AD dementia. CONCLUSION: Findings of this systematic review identified that the possibility of using neuroimaging data processed by advanced learning algorithms is promising for the prediction of AD progression. We also provided a detailed description of the challenges that researchers are faced along with future research directions. The protocol has been registered in the International Prospective Register of Systematic Reviews- CRD42019133402 and published in the Systematic Reviews journal.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Algoritmos , Aprendizaje Automático , Neuroimagen
3.
Pestic Biochem Physiol ; 195: 105521, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37666627

RESUMEN

The use of pesticides in the past century has lot helped humankind in improving crops' field and general hygiene level. Nevertheless, there has been countless evidences on the toxic effects of pesticides on the living systems. The link of exposure to pesticides with different human chronic diseases in the context of carcinogenicity, neurotoxicity, developmental toxicity, etc., have been evaluated in various types of studies. There are also some evidences on the link of exposure to pesticides with higher incidence of metabolic diseases associated with insulin resistance like diabetes, obesity, metabolic syndrome, hypertension, polycystic ovary syndrome and chronic kidney diseases. Physiologically, weakening intracellular insulin signaling is considered as a compensatory mechanism for cells to cope with cellular stresses like xenobiotic effects, oxidative stress and inflammatory responses, but it can pathologically lead to a defective cycle with lowered sensitivity of the cells to insulin which happens in metabolic disorders. In this work, the data related to metabolic toxicity of pesticides categorized in the mentioned metabolic diseases with a focus on the effects of pesticides on insulin signaling pathway and the mechanisms of development of insulin resistance will be systematically reviewed and presented.


Asunto(s)
Resistencia a la Insulina , Insulinas , Enfermedades Metabólicas , Plaguicidas , Humanos , Femenino , Plaguicidas/toxicidad , Enfermedades Metabólicas/inducido químicamente , Transducción de Señal
4.
Hosp Pharm ; 58(5): 484-490, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37711413

RESUMEN

Introduction: Drug-drug interactions (DDIs) can reduce therapeutic efficacy and increase the duration and cost of hospitalization so that patients are sometimes exposed to significant complications and even death. Patients in the intensive care unit (ICU) are at higher risk of DDIs for a variety of reasons, including impaired absorption, decreased metabolism, and renal failure. The main objective of this study was to evaluate frequency, clinical ranking and risk factors of potential DDIs in the ICUs of 3 teaching hospitals in Ardabil. Methods: In this descriptive-analytical cross-sectional study, drug prescriptions 355 patients admitted to the ICUs were studied. Patient information including age, sex, diagnosis, number of prescribers, number of drugs, length of stay, and status of patients' discharge (recovery or death) were recorded and checked using the online software up to date and the book Drug Interaction Facts. Finally, the data were statistically analyzed using the SPSS software. Results: The number of patients studied was 355. The mean age of the patients were 51.88 ± 23.22 years, and on average, 8.45 drugs had been prescribed for each patient. The total number of DDIs was 1597 among which class X was 1.4%, class D was 26.2%, and class C was 67.7%. Four hundred ninety-seven unique pairs of DDIs were identified. Age, number of prescribed drugs and length of stay in ICU were associated with prevalence of DDIs. Age and number of drugs were also identified as the risk factors of patients' discharge caused by death. Conclusion: DDIs can complicate health state of patients in ICUs and may increase the length of hospital stay. Setting up computerized systems to alert drug interactions in hospital wards and pharmacotherapeutic intervention by clinical pharmacist can minimize DDIs.

5.
Int J Environ Health Res ; 32(12): 2718-2755, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34663153

RESUMEN

Following the introduction and application of pesticides in human life, they have always been along with health concerns both in acute poisoning and chronic toxicities. Neurotoxicity of pesticides in chronic exposures has been known as one of the most important human health problems, as most of these chemicals act through interacting with some elements of nervous system. Pesticide-induced neurotoxicity can be defined in different categories of neurological disorders including neurodegenerative (Alzheimer, Parkinson, amyotrophic lateral sclerosis, multiple sclerosis), neurodevelopmental (attention deficit hyperactivity disorder, autism spectrum disorders, developmental delay, and intellectual disability), neurobehavioral and neuropsychiatric (depression/suicide attempt, anxiety/insomnia, and cognitive impairment) disorders some of which are among the most debilitating human health problems. In this review, neurotoxicity of pesticides in the mentioned categories and sub-categories of neurological diseases have been systematically presented in relation to different route of exposures including general, occupational, environmental, prenatal, postnatal, and paternal.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Síndromes de Neurotoxicidad , Plaguicidas , Embarazo , Femenino , Humanos , Plaguicidas/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Síndromes de Neurotoxicidad/etiología , Enfermedad Crónica , Trastorno por Déficit de Atención con Hiperactividad/inducido químicamente
6.
Stat Med ; 40(12): 2922-2938, 2021 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-33728679

RESUMEN

Age-adjusted rates are frequently used by epidemiologists to compare disease incidence and mortality across populations. In small geographic regions, age-adjusted rates computed directly from the data are subject to considerable variability and are generally unreliable. Therefore, we desire an approach that accounts for the excessive number of zero counts in disease mapping datasets, which are naturally present for low-prevalence diseases and are further innated when stratifying by age group. Bayesian modeling approaches are naturally suited to employ spatial and temporal smoothing to produce more stable estimates of age-adjusted rates for small areas. We propose a Bayesian hierarchical spatio-temporal hurdle model for counts and demonstrate how age-adjusted rates can be estimated from the hurdle model. We perform a simulation study to evaluate the performance of the proposed model vs a traditional Poisson model on datasets with varying characteristics. The approach is illustrated using two applications to cancer mortality at the county level.


Asunto(s)
Teorema de Bayes , Simulación por Computador , Humanos , Prevalencia
7.
PLoS Comput Biol ; 14(3): e1006020, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29513661

RESUMEN

The surveillance of influenza activity is critical to early detection of epidemics and pandemics and the design of disease control strategies. Case reporting through a voluntary network of sentinel physicians is a commonly used method of passive surveillance for monitoring rates of influenza-like illness (ILI) worldwide. Despite its ubiquity, little attention has been given to the processes underlying the observation, collection, and spatial aggregation of sentinel surveillance data, and its subsequent effects on epidemiological understanding. We harnessed the high specificity of diagnosis codes in medical claims from a database that represented 2.5 billion visits from upwards of 120,000 United States healthcare providers each year. Among influenza seasons from 2002-2009 and the 2009 pandemic, we simulated limitations of sentinel surveillance systems such as low coverage and coarse spatial resolution, and performed Bayesian inference to probe the robustness of ecological inference and spatial prediction of disease burden. Our models suggest that a number of socio-environmental factors, in addition to local population interactions, state-specific health policies, as well as sampling effort may be responsible for the spatial patterns in U.S. sentinel ILI surveillance. In addition, we find that biases related to spatial aggregation were accentuated among areas with more heterogeneous disease risk, and sentinel systems designed with fixed reporting locations across seasons provided robust inference and prediction. With the growing availability of health-associated big data worldwide, our results suggest mechanisms for optimizing digital data streams to complement traditional surveillance in developed settings and enhance surveillance opportunities in developing countries.


Asunto(s)
Gripe Humana/epidemiología , Vigilancia de la Población/métodos , Teorema de Bayes , Simulación por Computador , Bases de Datos Factuales , Humanos , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Registros Médicos , Modelos Teóricos , Sistemas en Línea , Pandemias , Sesgo de Selección , Vigilancia de Guardia , Estados Unidos
8.
Malar J ; 13: 126, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24678602

RESUMEN

BACKGROUND: Malaria is a leading cause of mortality worldwide. There is currently conflicting data and interpretation on how variability in climate factors affects the incidence of malaria. This study presents a hierarchical Bayesian modelling framework for the analysis of malaria versus climate factors in West Africa. METHODS: The hierarchical Bayesian framework takes into account spatiotemporal dependencies, and in this paper is applied to annual malaria and climate data from ten West African countries (Benin, Burkina Faso, Côte d'Ivoire, Gambia, Ghana, Liberia, Mali, Senegal, Sierra Leone, and Togo) during the period 1996-2006. RESULTS: Results show a statistically significant correspondence between malaria rates and the climate variables considered. The two most important climate factors are found to be average annual temperature and total annual precipitation, and they show negative association with malaria incidence. CONCLUSIONS: This modelling framework provides a useful approach for studying the impact of climate variability on the spread of malaria and may help to resolve some conflicting interpretations in the literature.


Asunto(s)
Clima , Malaria/epidemiología , Plasmodium/fisiología , Tiempo (Meteorología) , África Occidental/epidemiología , Teorema de Bayes , Humanos , Incidencia , Malaria/parasitología , Modelos Teóricos
9.
BMC Public Health ; 14: 850, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25127906

RESUMEN

BACKGROUND: Infectious disease surveillance is a process the product of which reflects both actual disease trends and public awareness of the disease. Decisions made by patients, health care providers, and public health professionals about seeking and providing health care and about reporting cases to health authorities are all influenced by the information environment, which changes constantly. Biases are therefore imbedded in surveillance systems; these biases need to be characterized to provide better situational awareness for decision-making purposes. Our goal is to develop a statistical framework to characterize influenza surveillance systems, particularly their correlation with the information environment. METHODS: We identified Hong Kong influenza surveillance data systems covering healthcare providers, laboratories, daycare centers and residential care homes for the elderly. A Bayesian hierarchical statistical model was developed to examine the statistical relationships between the influenza surveillance data and the information environment represented by alerts from HealthMap and web queries from Google. Different models were fitted for non-pandemic and pandemic periods and model goodness-of-fit was assessed using common model selection procedures. RESULTS: Some surveillance systems - especially ad hoc systems developed in response to the pandemic flu outbreak - are more correlated with the information environment than others. General practitioner (percentage of influenza-like-illness related patient visits among all patient visits) and laboratory (percentage of specimen tested positive) seem to proportionally reflect the actual disease trends and are less representative of the information environment. Surveillance systems using influenza-specific code for reporting tend to reflect biases of both healthcare seekers and providers. CONCLUSIONS: This study shows certain influenza surveillance systems are less correlated with the information environment than others, and therefore, might represent more reliable indicators of disease activity in future outbreaks. Although the patterns identified in this study might change in future outbreaks, the potential susceptibility of surveillance data is likely to persist in the future, and should be considered when interpreting surveillance data.


Asunto(s)
Gripe Humana/epidemiología , Vigilancia de la Población , Adolescente , Adulto , Anciano , Teorema de Bayes , Niño , Preescolar , Femenino , Hong Kong/epidemiología , Humanos , Lactante , Recién Nacido , Gripe Humana/prevención & control , Internet , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Reproducibilidad de los Resultados
10.
Sci Rep ; 14(1): 16734, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39030306

RESUMEN

The interactions of environmental, geographic, socio-demographic, and epidemiological factors in shaping mosquito-borne disease transmission dynamics are complex and changeable, influencing the abundance and distribution of vectors and the pathogens they transmit. In this study, 27 years of cross-sectional malaria survey data (1990-2017) were used to examine the effects of these factors on Plasmodium falciparum and Plasmodium vivax malaria presence at the community level in Africa and Asia. Monthly long-term, open-source data for each factor were compiled and analyzed using generalized linear models and classification and regression trees. Both temperature and precipitation exhibited unimodal relationships with malaria, with a positive effect up to a point after which a negative effect was observed as temperature and precipitation increased. Overall decline in malaria from 2000 to 2012 was well captured by the models, as was the resurgence after that. The models also indicated higher malaria in regions with lower economic and development indicators. Malaria is driven by a combination of environmental, geographic, socioeconomic, and epidemiological factors, and in this study, we demonstrated two approaches to capturing this complexity of drivers within models. Identifying these key drivers, and describing their associations with malaria, provides key information to inform planning and prevention strategies and interventions to reduce malaria burden.


Asunto(s)
Malaria Falciparum , Humanos , Estudios Transversales , África/epidemiología , Asia/epidemiología , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria Falciparum/transmisión , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Malaria Vivax/transmisión , Factores Socioeconómicos , Geografía , Plasmodium falciparum , Malaria/epidemiología , Malaria/transmisión , Temperatura , Mosquitos Vectores/parasitología , Animales , Plasmodium vivax , Ambiente
11.
Oecologia ; 173(2): 331-41, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23604861

RESUMEN

While numerous studies have examined the effects of increased primary production on higher trophic levels, most studies have focused primarily on the grazing food web and have not considered the importance of alternate prey channels. This has happened despite the fact that fertilization not only increases grazing herbivore abundance, but other types of consumers such as detritivores that serve as alternate prey for generalist predators. Alternate prey channels can sustain generalist predators at times when prey abundance in the grazing food web is low, thus increasing predator densities and the potential for trophic cascades. Using arthropod data from a fertilization experiment, we constructed a hierarchical Bayesian model to examine the direct and indirect effects of plant production and alternate prey channels on predators in a salt marsh. We found that increased plant production positively affected the density of top predators via effects on lower trophic level herbivores and mesopredators. Additionally, while the abundance of algivores and detritivores positively affected mesopredators and top predators, respectively, the effects of alternate prey were relatively weak. Because previous studies in the same system have found that mesopredators and top predators rely on alternate prey such as algivores and detritivores, future studies should examine whether fertilization shifts patterns of prey use by predators from alternate channels to the grazing channel. Finally, the hierarchical Bayesian model used in this study provided a useful method for exploring trophic relationships in the salt marsh food web, especially where causal relationships among trophic groups were unknown.


Asunto(s)
Artrópodos/fisiología , Cadena Alimentaria , Desarrollo de la Planta , Humedales , Animales , Teorema de Bayes , Biomasa , Modelos Biológicos , New Jersey , Densidad de Población , Estaciones del Año
12.
Am J Physiol Regul Integr Comp Physiol ; 303(3): R311-20, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22696574

RESUMEN

In the brains of teleosts, angiotensin II (ANG II), one of the main effector peptides of the renin-angiotensin system, is implicated in various physiological functions notably body fluid and electrolyte homeostasis and cardiovascular regulation, but nothing is known regarding the potential action of ANG II and other angiotensin derivatives on ventilation. Consequently, the goal of the present study was to determine possible ventilatory and cardiovascular effects of intracerebroventricular injection of picomole doses (5-100 pmol) of trout [Asn(1)]-ANG II, [Asp(1)]-ANG II, ANG III, ANG IV, and ANG 1-7 into the third ventricle of unanesthetized trout. The central actions of these peptides were also compared with their ventilatory and cardiovascular actions when injected peripherally. Finally, we examined the presence of [Asn(1)]-ANG II, [Asp(1)]-ANG II, ANG III, and ANG IV in the brain and plasma using radioimmunoassay coupled with high-performance liquid chromatography. After intracerebroventricular injection, [Asn(1)]-ANG II and [Asp(1)]-ANG II two ANG IIs, elevated the total ventilation through a selective stimulatory action on the ventilation amplitude. However, the hyperventilatory effect of [Asn(1)]-ANG II was threefold higher than the effect of [Asp(1)]-ANG II at the 50-pmol dose. ANG III, ANG IV, and ANG 1-7 were without effect. In addition, ANG IIs and ANG III increased dorsal aortic blood pressure (P(DA)) and heart rate (HR). After intra-arterial injections, none of the ANG II peptides affected the ventilation but [Asn(1)]-ANG II, [Asp(1)]-ANG II, and ANG III elevated P(DA) (50 pmol: +80%, +58% and +48%, respectively) without significant decrease in HR. In brain tissue, comparable amounts of [Asn(1)]-ANG II and [Asp(1)]-ANG II were detected (ca. 40 fmol/mg brain tissue), but ANG III was not detected, and the amount of ANG IV was about eightfold lower than the content of the ANG IIs. In plasma, ANG IIs were also the major angiotensins (ca. 110 fmol/ml plasma), while significant but lower amounts of ANG III and ANG IV were present in plasma. In conclusion, our study suggests that the two ANG II isoforms produced within the brain may act as a neurotransmitter and/or neuromodulator to regulate the cardioventilatory functions in trout. In the periphery, two ANG IIs and their COOH-terminal peptides may act as a circulating hormone preferentially involved in cardiovascular regulations.


Asunto(s)
Angiotensina III/farmacología , Angiotensina II/análogos & derivados , Angiotensina II/farmacología , Angiotensina I/farmacología , Fenómenos Fisiológicos Cardiovasculares/efectos de los fármacos , Branquias/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Trucha/fisiología , Angiotensina I/administración & dosificación , Angiotensina II/administración & dosificación , Angiotensina III/administración & dosificación , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Branquias/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Inyecciones Intraventriculares , Masculino , Fragmentos de Péptidos/administración & dosificación , Factores de Tiempo
13.
Materials (Basel) ; 15(4)2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35208142

RESUMEN

In recent years, additive manufacturing of ceramics is becoming of increasing interest due to the possibility of the fabrication of complex shaped parts. However, the fabrication of a fully dense bulk ceramic part without cracks and defects is still challenging. In the presented work, the digital light processing method was introduced for fabricating zirconia parts. The flexural properties of the printed zirconia were systematically investigated via a three-point bending test with the digital image correlation method, scanning electron microscopy observation and fractography analysis. Due to the anisotropy of the sample, the bending deformation behaviors of the zirconia samples in the parallel and vertical printing directions were significantly different. The flexural strength and the related elastic modulus of the samples under vertical loading were higher than that of the parallel loading, as the in-plane strength is higher than that of the interlayer strength. The maximum horizontal strain always appeared at the bottom center before the failure for the parallel loading case; while the maximum horizontal strain for the vertical loading moved upward from the bottom center to the top center. There was a clear dividing line between the minimum perpendicular strain and the maximum perpendicular strain of the samples under parallel loading; however, under vertical loading, the perpendicular strain declined from the bottom to the top along the crack path. The surrounding dense part of the sintered sample (a few hundred microns) was mainly composed of large and straight cracks between printing layers, whereas the interior contained numerous small winding cracks. The intense cracks inside the sample led to a low flexural property compared to other well-prepared zirconia samples, which the inadequate additive formulations would be the main reason for the generation of cracks. A better understanding of the additive formulation (particularly the dispersant) and the debinding-sintering process are necessary for future improvement.

14.
PLOS Digit Health ; 1(6): e0000039, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36812505

RESUMEN

Traditional disease surveillance is increasingly being complemented by data from non-traditional sources like medical claims, electronic health records, and participatory syndromic data platforms. As non-traditional data are often collected at the individual-level and are convenience samples from a population, choices must be made on the aggregation of these data for epidemiological inference. Our study seeks to understand the influence of spatial aggregation choice on our understanding of disease spread with a case study of influenza-like illness in the United States. Using U.S. medical claims data from 2002 to 2009, we examined the epidemic source location, onset and peak season timing, and epidemic duration of influenza seasons for data aggregated to the county and state scales. We also compared spatial autocorrelation and tested the relative magnitude of spatial aggregation differences between onset and peak measures of disease burden. We found discrepancies in the inferred epidemic source locations and estimated influenza season onsets and peaks when comparing county and state-level data. Spatial autocorrelation was detected across more expansive geographic ranges during the peak season as compared to the early flu season, and there were greater spatial aggregation differences in early season measures as well. Epidemiological inferences are more sensitive to spatial scale early on during U.S. influenza seasons, when there is greater heterogeneity in timing, intensity, and geographic spread of the epidemics. Users of non-traditional disease surveillance should carefully consider how to extract accurate disease signals from finer-scaled data for early use in disease outbreaks.

15.
J Funct Biomater ; 13(4)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36547562

RESUMEN

Irregular 3D biological scaffolds have been widely observed in nature. Therefore, in the current work, new designs are proposed for lightweight 3D scaffolds based on Voronoi tessellation with high porosity. The proposed designs are inspired by nature, which has undoubtedly proven to be the best designer. Thus, the Rhinoceros 7/Grasshopper software was used to design three geometric models for both normal and elongated Voronoi structures: homogeneous, gradient I, and gradient II. Then, stereolithography (SLA) additive manufacturing was utilized to fabricate biopolymeric materials. Finally, a compression test was carried out to study and compare the mechanical properties of the designed samples. The gradient I cylinder show the highest Young's modulus. For the Homogeneous and gradient II cylinders, elongated Voronoi structures show superior mechanical properties and energy absorption compared to normal Voronoi designs. Hence, these designs are promising topologies for future applications.

16.
Materials (Basel) ; 15(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36556665

RESUMEN

Prussian Blue (PB) thin films were prepared by DC chronoamperometry (CHA), symmetric pulse, and non-symmetric pulse electrodeposition techniques. The formation of PB was confirmed by infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX) and UV-Vis transmission measurements. X-ray diffraction (XRD) shows the stabilization of the insoluble form of PB. From scanning electron microscopy (SEM) studies, an increase in porosity is obtained for the shorter pulse widths, which tends to improve the total charge exchange and electrochemical stability of the films. While the film prepared by CHA suffered a degradation of 82% after 260 cycles, the degradation reduced to 24% and 34% for the samples prepared by the symmetric and non-symmetric pulse methods, respectively. Additionally, in the non-symmetric pulse film, the improvement in the charge exchange reached ~522% after 260 cycles. According to this study, the deposition time distribution affects the physical/chemical properties of PB films. These results then render pulse electrodeposition methods especially suitable to produce high-quality thin films for electrochemical devices, based on PB.

17.
Ticks Tick Borne Dis ; 12(6): 101822, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34555712

RESUMEN

Epidemiological data often include characteristics such as spatial and/or temporal dependencies and excess zero counts, which pose modeling challenges. Excess zeros in such data may arise from imperfect detection and/or relative rareness of the disease in a given location. Here, we studied the spatio-temporal variation in annual Lyme disease cases in Virginia from 2001-2016 and modeled the disease with a spatio-temporal hierarchical Bayesian model. Using observed ecological and environmental covariates, we constructed a predictive model for the disease spread over space and time, including spatial and temporal random effects. We considered several different models and found that the negative binomial hurdle model performs the best for such epidemiological data. Among the various ecological predictors, the North-South (V component) of winds and relative humidity significantly contributed to predicting the Lyme cases. Our model results provide important insights on the spread of the disease in Virginia and the proposed modeling framework offers epidemiologists and health policymakers a useful tool for improving disease preparedness and control plans for the future.


Asunto(s)
Enfermedad de Lyme/epidemiología , Humanos , Enfermedad de Lyme/transmisión , Modelos Estadísticos , Análisis Espacio-Temporal , Virginia/epidemiología
18.
Front Aging Neurosci ; 13: 693791, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34483879

RESUMEN

Introduction: Rates of dementia are projected to increase over the coming years as global populations age. Without a treatment to slow the progression of dementia, many health policies are focusing on preventing dementia by slowing the rate of cognitive decline with age. However, it is unclear which lifestyle changes in old age meaningfully reduce the rate of cognitive decline associated with aging. Objectives: Use existing, multi-year longitudinal health data to determine if engagement in a variety of different lifestyle activities can slow the rate of cognitive decline as older adults age. Method: Data from the English Longitudinal Study of Aging was analyzed using a quasi-experimental, efficient matched-pair design inspired by the clinical trial methodology. Changes in short-term memory scores were assessed over a multi-year interval for groups who undertook one of 11 different lifestyle activities, compared to control groups matched across confounding socioeconomic and lifestyle factors. Results: Two factors, moderate-intensity physical activity and learning activities, resulted in significant positive impact on cognitive function. Conclusion: Our analysis brings cognitive benefit arguments in favor of two lifestyle activities, moderate-intensity physical activity and learning activities, while rejecting other factors advanced by the literature such as vigorous-intensity physical activity. Those findings justify and encourage the development of new lifestyle health programs by health authorities and bring forward the new health system solution, social prescribing.

19.
J Med Entomol ; 58(4): 1680-1685, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-33825903

RESUMEN

Lyme disease is the most common tick-borne disease in North America. Though human infection is mostly transmitted in a limited geography, the range has expanded in recent years. One notable area of recent expansion is in the mountainous region of southwestern Virginia. The ecological factors that facilitate or constrain the range of human Lyme disease in this region remain uncertain. To evaluate this further, we obtained ecological data, including remotely sensed data on forest structure and vegetation, weather data, and elevation. These data were aggregated within the census block groups of a 9,153 km2 area around the cities of Blacksburg and Roanoke, VA, an area with heterogeneous Lyme disease transmission. In this geographic area, 755 individuals were reported to have Lyme disease in the 10 yr from 2006 to 2015, and these cases were aggregated by block group. A zero-inflated negative binomial model was used to evaluate which environmental variables influenced the abundance of Lyme disease cases. Higher elevation and higher vegetation density had the greatest effect size on the abundance of Lyme disease. Measures of forest edge, forest integrity, temperature, and humidity were not associated with Lyme disease cases. Future southward expansion of Lyme disease into the southeastern states may be most likely in ecologically similar mountainous areas.


Asunto(s)
Ambiente , Enfermedad de Lyme/epidemiología , Enfermedades Transmisibles Emergentes , Estudios Transversales , Humanos , Estudios Retrospectivos , Virginia/epidemiología
20.
Nat Ecol Evol ; 5(7): 987-994, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33927370

RESUMEN

Animals and plants are shifting the timing of key life events in response to climate change, yet despite recent documentation of escalating phenological change, scientists lack a full understanding of how and why phenological responses vary across space and among species. Here, we used over 7 million community-contributed bird observations to derive species-specific, spatially explicit estimates of annual spring migration phenology for 56 bird species across eastern North America. We show that changes in the spring arrival of migratory birds are coarsely synchronized with fluctuations in vegetation green-up and that the sensitivity of birds to plant phenology varied extensively. Bird arrival responded more synchronously with vegetation green-up at higher latitudes, where phenological shifts over time are also greater. Critically, species' migratory traits explained variation in sensitivity to green-up, with species that migrate more slowly, arrive earlier and overwinter further north showing greater responsiveness to earlier springs. Identifying how and why species vary in their ability to shift phenological events is fundamental to predicting species' vulnerability to climate change. Such variation in sensitivity across taxa, with long-distance neotropical migrants exhibiting reduced synchrony, may help to explain substantial declines in these species over the last several decades.


Asunto(s)
Migración Animal , Aves , Animales , Cambio Climático , Fenotipo , Estaciones del Año
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