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1.
Chemistry ; 30(22): e202304114, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38311596

RESUMEN

Lithium-selenium (Li-Se) batteries are promising energy storage devices. However, the long-term durability and high-rate performance of the Se cathode have been limited by significant volume expansion and the troublesome shuttle effect of polyselenides during repeated charging/discharging processes. To revolutionize these issues, we applied a top-down strategy through the in-situ trapping of amorphous Se within bubble-like carbon (BLC) frameworks, which can radically minimize the presence of surface-absorbed Se while enhancing Se loading capacity. This ingenious technique successfully encapsulates all Se species within carbon nanoshells, creating a distinct half-filled core-shell structure known as Se@void@BLC. This in-situ trapping approach ensures the efficient management of Se volume changes during repeated discharge and charge cycles. Moreover, an extraordinary Se loading capacity of up to 65.6 wt% is reached. Using the Se@void@BLC as cathode for Li-Se battery, we achieve a high initial Columbic efficiency of 84.2 %, a high reversible capacity of 585 mAh g-1, and an ultralow capacity decay of only 0.0037 % per cycle during 4000 cycles at 10 A g-1.

2.
J Am Chem Soc ; 144(13): 6028-6039, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35302356

RESUMEN

Water-alkaline electrolysis holds a great promise for industry-scale hydrogen production but is hindered by the lack of enabling hydrogen evolution reaction electrocatalysts to operate at ampere-level current densities under low overpotentials. Here, we report the use of hydrogen spillover-bridged water dissociation/hydrogen formation processes occurring at the synergistically hybridized Ni3S2/Cr2S3 sites to incapacitate the inhibition effect of high-current-density-induced high hydrogen coverage at the water dissociation site and concurrently promote Volmer/Tafel processes. The mechanistic insights critically important to enable ampere-level current density operation are depicted from the experimental and theoretical studies. The Volmer process is drastically boosted by the strong H2O adsorption at Cr5c sites of Cr2S3, the efficient H2O* dissociation via a heterolytic cleavage process (Cr5c-H2O* + S3c(#) → Cr5c-OH* + S3c-H#) on the Cr5c/S3c sites in Cr2S3, and the rapid desorption of OH* from Cr5c sites of Cr2S3 via a new water-assisted desorption mechanism (Cr5c-OH* + H2O(aq) → Cr5c-H2O* + OH-(aq)), while the efficient Tafel process is achieved through hydrogen spillover to rapidly transfer H# from the synergistically located H-rich site (Cr2S3) to the H-deficient site (Ni3S2) with excellent hydrogen formation activity. As a result, the hybridized Ni3S2/Cr2S3 electrocatalyst can readily achieve a current density of 3.5 A cm-2 under an overpotential of 251 ± 3 mV in 1.0 M KOH electrolyte. The concept exemplified in this work provides a useful means to address the shortfalls of ampere-level current-density-tolerant Hydrogen evolution reaction (HER) electrocatalysts.

3.
Small ; 18(10): e2105761, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35266313

RESUMEN

Rechargeable aqueous zinc-ion batteries (ZIBs) are promising in stationary grid energy storage due to their advantages in safety and cost-effectiveness, and the search for competent cathode materials is one core task in the development of ZIBs. Herein, the authors design a 2D heterostructure combining amorphous vanadium pentoxide and electrochemically produced graphene oxide (EGO) using a fast and scalable spray drying technique. The unique 2D heterostructured xerogel is achieved by controlling the concentration of EGO in the precursor solution. Driven by the improved electrochemical kinetics, the resultant xerogel can deliver an excellent rate capability (334 mAh g-1 at 5 A g-1 ) as well as a high specific capacity (462 mAh g-1 at 0.2 A g-1 ) as the cathode material in ZIB. It is also shown that the coin cell constructed based on spray-dried xerogel can output steady, high energy densities over a broad power density window. This work provides a scalable and cost-effective approach for making high performance electrode materials from cheap sources through existing industrialized materials processing.

4.
Proc Biol Sci ; 289(1976): 20212727, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35673869

RESUMEN

To quantify the potential impact of rotavirus vaccines and identify strategies to improve vaccine performance in Bangladesh, a better understanding of the drivers of pre-vaccination rotavirus patterns is required. We developed and fitted mathematical models to 23 years (1990-2012) of weekly rotavirus surveillance data from Dhaka with and without incorporating long-term and seasonal variation in the birth rate and meteorological factors. We performed external model validation using data between 2013 and 2019 from the regions of Dhaka and Matlab. The models showed good agreement with the observed age distribution of rotavirus cases and captured the observed shift in seasonal patterns of rotavirus hospitalizations from biannual to annual peaks. The declining long-term trend in the birth rate in Bangladesh was the key driver of the observed shift from biannual to annual winter rotavirus patterns. Meteorological indices were also important: a 1°C, 1% and 1 mm increase in diurnal temperature range, surface water presence and degree of wetness were associated with a 19%, 3.9% and 0.6% increase in the transmission rate, respectively. The model demonstrated reasonable predictions for both Dhaka and Matlab, and can be used to evaluate the impact of rotavirus vaccination in Bangladesh against changing patterns of disease incidence.


Asunto(s)
Infecciones por Rotavirus , Vacunas contra Rotavirus , Rotavirus , Bangladesh/epidemiología , Tasa de Natalidad , Clima , Humanos , Lactante , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/prevención & control
5.
Phys Rev Lett ; 126(6): 061101, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33635682

RESUMEN

We perform a joint Bayesian inference of neutron-star mass and radius constraints based on GW170817, observations of quiescent low-mass x-ray binaries (QLMXBs), photospheric radius expansion x-ray bursting sources, and x-ray timing observations of J0030+0451. With this dataset, the form of the prior distribution still has an impact on the posterior mass-radius curves and equation of state (EOS), but this impact is smaller than recently obtained when considering QLMXBs alone. We analyze the consistency of the electromagnetic data by including an "intrinsic scattering" contribution to the uncertainties, and find only a slight broadening of the posteriors. This suggests that the gravitational-wave and electromagnetic observations of neutron-star structure are providing a consistent picture of the neutron-star mass-radius curve and the EOS.

6.
Ann Pharmacother ; 55(4): 421-429, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32929977

RESUMEN

INTRODUCTION: The Medication Regimen Complexity -Intensive Care Unit (MRC-ICU) is the first tool for measuring medication regimen complexity in critically ill patients. This study tested machine learning (ML) models to investigate the relationship between medication regimen complexity and patient outcomes. METHODS: This study was a single-center, retrospective observational evaluation of 130 adults admitted to the medical ICU. The MRC-ICU score was utilized to improve the inpatient model's prediction accuracy. Three models were proposed: model I, demographic data without medication data; model II, demographic data and medication regimen complexity variables; and model III: demographic data and the MRC-ICU score. A total of 6 ML classifiers was developed: k-nearest neighbor (KNN), naïve Bayes (NB), random forest, support vector machine, neural network, and logistic classifier (LC). They were developed and tested using electronic health record data to predict inpatient mortality. RESULTS: The results demonstrated that adding medication regimen complexity variables (model II) and the MRC-ICU score (model III) improved inpatient mortality prediction.. The LC outperformed the other classifiers (KNN and NB), with an overall accuracy of 83%, sensitivity (Se) of 87%, specificity of 67%, positive predictive value of 93%, and negative predictive value of 46%. The APACHE III score and the MRC-ICU score at the 24-hour interval were the 2 most important variables. CONCLUSION AND RELEVANCE: Inclusion of the MRC-ICU score improved the prediction of patient outcomes on the previously established APACHE III score. This novel, proof-of-concept methodology shows promise for future application of the MRC-ICU scoring tool for patient outcome predictions.


Asunto(s)
APACHE , Enfermedad Crítica/terapia , Aprendizaje Automático/normas , Conciliación de Medicamentos/normas , Adulto , Anciano , Anciano de 80 o más Años , Teorema de Bayes , Femenino , Mortalidad Hospitalaria/tendencias , Hospitalización/tendencias , Humanos , Unidades de Cuidados Intensivos/normas , Unidades de Cuidados Intensivos/tendencias , Masculino , Conciliación de Medicamentos/métodos , Persona de Mediana Edad , Estudios Retrospectivos
7.
Eur Heart J Suppl ; 23(Suppl B): B21-B23, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34054361

RESUMEN

According to the Non-communicable disease Risk Factors Survey of 2018, more than one-fifth (21.0%) of adults aged 25 years or older have hypertension and one-third of the adults did not have their blood pressure (BP) measured in their lifetime in Bangladesh. The National Heart Foundation of Bangladesh participated in May Measurement Month (MMM) 2017 and 2018 as well as this 2019 as a part of a global initiative aimed at raising awareness of high BP and to act as a temporary solution to the lack of screening programmes worldwide. This opportunistic screening of voluntary participants aged ≥18 years was carried out from May to July 2019. Data were collected from 100 screening sites in 16 districts in Bangladesh. BP measurement, the definition of hypertension, and statistical analysis followed the MMM protocol. Data on 24 941 individuals were analysed. Among the participants, 12 658 (50.8%) were female. After multiple imputation, 6990 (28.0%) had hypertension. Among the 6990 participants with hypertension, 5007 (71.6%) were on antihypertensive medication and 5331 (76.3%) were aware of having hypertension. Among 6990 participants with hypertension, 3217 (46.0%) had controlled BP (<140/90 mmHg) and among the participants with hypertension and on antihypertensive medication, 64.2% had controlled BP. Opportunistic BP screening can identify significant numbers of people with raised BP and thus assist in the prevention of cardiovascular diseases.

8.
J Intellect Disabil ; : 17446295211002355, 2021 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-33882755

RESUMEN

This cross-sectional study explored stressful situations of caregivers related to life events of their children suffering from neurodevelopmental disorders along with potential contributing factors. A total of 906 caregivers of children with diagnosed neurodevelopmental disorder, from eight administrative districts and two city corporation areas in Bangladesh were interviewed. The Family Stress and Coping Interview scale was used to evaluate parenting stress. The diagnosis of neurodevelopmental disorder at the outset, feelings about the cause of the disorder, future planning for employment and accommodation for the child and dealing with child sexuality were some important stressful situations for parents. Parenting stress is found to be higher among female [regression coefficient (B) = 5.09, p < 0.001] and less educated caregivers [B = 2.69, p < 0.01]. Increasing age of child [B = 0.82, p < 0.001] and diagnosis of neurodevelopmental disorder before child's second birthday [B = 4.22, p < 0.001] are also associated with higher parenting stress.

9.
J Infect Dis ; 221(10): 1669-1676, 2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-31875229

RESUMEN

BACKGROUND: Pneumococcus is a diverse pathogen, with >90 serotypes, each of which has a distinct polysaccharide capsule. Pneumococci can switch capsules, evading vaccine pressure. Certain serotype pairs are more likely to occur on the same genetic background as a results of serotype switching, but the drivers of these patterns are not well understood. METHODS: We used the PubMLST and Global Pneumococcal Sequencing Project databases to quantify the number of genetic lineages on which different serotype pairs occur together. We also quantified the genetic diversity of each serotype. Regression model were used to evaluate the relationship between shared polysaccharide components and the frequency of serotype co-occurrence and diversity. RESULTS: A number of serotype pairs occurred together on the same genetic lineage more commonly than expected. Co-occurrence of between-serogroup pairs was more common when both serotypes had glucose as a component of the capsule (and, potentially, glucuronic acid, any-N-acetylated sugar, or ribitol). Diversity also varied markedly by serotype and was associated with the presence of specific sugars in the capsule. CONCLUSIONS: Certain pairs of serotypes are more likely to co-occur on the same genetic background. These patterns were correlated with shared polysaccharide components. This might reflect adaptation of strains to produce capsules with specific characteristics.


Asunto(s)
Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/genética , Bases de Datos Genéticas , Humanos , Infecciones Neumocócicas/microbiología , Serogrupo , Serotipificación
10.
Eur Heart J Suppl ; 22(Suppl H): H20-H22, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32884460

RESUMEN

Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. According to Non-communicable disease (NCD) Risk Factors Survey Bangladesh 2010, one-fifth (21.9%) of adults aged 25 years or more have hypertension. Almost one-third of the adult population did not have their BP measured in their lifetime in Bangladesh. National Heart Foundation of Bangladesh participated in May Measurement Month (MMM) 2018 as a part of a global initiative aimed at raising awareness of high BP and to act as a temporary solution to the lack of screening programmes nationally. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in May 2018. Blood pressure measurement, the definition of hypertension and statistical analysis followed the MMM protocol. Data were collected from 10 screening sites in 9 districts in Bangladesh. A total of 5208 individuals were screened during MMM18. After multiple imputation, 1750 (33.6%) had hypertension. Among the 1750 participants with hypertension, 1312 (75.0%) were aware of having hypertension. Among those that were not on antihypertensive medication, 15.2% were hypertensive and among those that were on antihypertensive medication 33.6% had uncontrolled hypertension. The present study showed that opportunistic screening can identify significant numbers of people with raised BP. A periodic public health programme at a national level needs to be initiated to increase hypertension detection and control rates and thus for prevention of cardiovascular diseases.

11.
BMC Public Health ; 19(1): 1002, 2019 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-31345186

RESUMEN

BACKGROUND: Developing strategies aimed at reducing behavioral risk factors and hence the prevalence of non-communicable diseases (NCDs) is a major challenge to the policy makers today. Like the same age group worldwide, the prevalence of obesity, unhealthy dietary habit, physical inactivity, smoking and alcohol intake is high among the adolescents of Bangladesh. Studies showed promising results of an early intervention at adolescent age in reducing the likelihood of NCDs at adult age. So, this study is designed to implement a behavior change intervention and evaluate the effectiveness of the intervention in reducing the behavioral risk factors of NCDs among the adolescents of Bangladesh. METHODS: A before-after designed intervention study will be conducted in two randomly selected secondary schools- one will be selected randomly as intervention school and the another as control school. A baseline survey will be conducted among the students of both schools by a pre-tested questionnaire to attain their current status of knowledge, attitude and practices related to NCDs. Afterward, students will be enrolled in the intervention group who will meet the eligibility criteria from the intervention school. The intervention will be given through a health promotion session to a group of students, not more than 25 at a time, by trained facilitators. A post-intervention end line survey will be conducted among all the participants from both schools using the same questionnaire 3 months after the baseline survey. DISCUSSION: An intervention has been developed based on some principals of two psychosocial theory- Motivational Interview and Social Cognitive Theory. Emphasis will be given on motivating the adolescents towards a healthy lifestyle, supporting self-efficacy to be changed, guiding self-regulatory ways along with facilitating desired changing process by empowering them with choices about the preventive measures of NCDs. This intervention is expected to increase awareness by equipping the adolescents with specific knowledge and skills and thus, facilitate an eventual change in their practiced risk behaviors. Besides, this intervention will address multiple behaviors at a time, and will be delivered to a group of adolescents, to attain the cost-effectiveness and thereby making it more realistic in the resource-poor context of Bangladesh. TRIAL REGISTRATION: ClinicalTrials.gov NCT03975335, registered on 01.06.2019. Retrospectively registered.


Asunto(s)
Educación en Salud , Enfermedades no Transmisibles/prevención & control , Conducta de Reducción del Riesgo , Servicios de Salud Escolar , Adolescente , Bangladesh , Femenino , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Proyectos de Investigación , Factores de Riesgo
12.
Angew Chem Int Ed Engl ; 58(26): 8824-8828, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31050110

RESUMEN

The poor cycling stability resulting from the large volume expansion caused by lithiation is a critical issue for Si-based anodes. Herein, we report for the first time of a new yolk-shell structured high tap density composite made of a carbon-coated rigid SiO2 outer shell to confine multiple Si NPs (yolks) and carbon nanotubes (CNTs) with embedded Fe2 O3 nanoparticles (NPs). The high tap density achieved and superior conductivity can be attributed to the efficiently utilised inner void containing multiple Si yolks, Fe2 O3 NPs, and CNTs Li+ storage materials, and the bridged spaces between the inner Si yolks and outer shell through a conductive CNTs "highway". Half cells can achieve a high area capacity of 3.6 mAh cm-2 and 95 % reversible capacity retention after 450 cycles. The full cell constructed using a Li-rich Li2 V2 O5 cathode can achieve a high reversible capacity of 260 mAh g-1 after 300 cycles.

13.
Appl Environ Microbiol ; 84(17)2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29959243

RESUMEN

Fresh produce supply chains present variable and diverse conditions that are relevant to food quality and safety because they may favor microbial growth and survival following contamination. This study presents the development of a simulation and visualization framework to model microbial dynamics on fresh produce moving through postharvest supply chain processes. The postharvest supply chain with microbial travelers (PSCMT) tool provides a modular process modeling approach and graphical user interface to visualize microbial populations and evaluate practices specific to any fresh produce supply chain. The resulting modeling tool was validated with empirical data from an observed tomato supply chain from Mexico to the United States, including the packinghouse, distribution center, and supermarket locations, as an illustrative case study. Due to data limitations, a model-fitting exercise was conducted to demonstrate the calibration of model parameter ranges for microbial indicator populations, i.e., mesophilic aerobic microorganisms (quantified by aerobic plate count and here termed APC) and total coliforms (TC). Exploration and analysis of the parameter space refined appropriate parameter ranges and revealed influential parameters for supermarket indicator microorganism levels on tomatoes. Partial rank correlation coefficient analysis determined that APC levels in supermarkets were most influenced by removal due to spray water washing and microbial growth on the tomato surface at postharvest locations, while TC levels were most influenced by growth on the tomato surface at postharvest locations. Overall, this detailed mechanistic dynamic model of microbial behavior is a unique modeling tool that complements empirical data and visualizes how postharvest supply chain practices influence the fate of microbial contamination on fresh produce.IMPORTANCE Preventing the contamination of fresh produce with foodborne pathogens present in the environment during production and postharvest handling is an important food safety goal. Since studying foodborne pathogens in the environment is a complex and costly endeavor, computer simulation models can help to understand and visualize microorganism behavior resulting from supply chain activities. The postharvest supply chain with microbial travelers (PSCMT) model, presented here, provides a unique tool for postharvest supply chain simulations to evaluate microbial contamination. The tool was validated through modeling an observed tomato supply chain. Visualization of dynamic contamination levels from harvest to the supermarket and analysis of the model parameters highlighted critical points where intervention may prevent microbial levels sufficient to cause foodborne illness. The PSCMT model framework and simulation results support ongoing postharvest research and interventions to improve understanding and control of fresh produce contamination.


Asunto(s)
Simulación por Computador , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos/métodos , Enfermedades Transmitidas por los Alimentos/prevención & control , Solanum lycopersicum/microbiología , Verduras/microbiología , Recuento de Colonia Microbiana , Granjas , Manipulación de Alimentos/métodos , Inocuidad de los Alimentos/métodos , México , Modelos Teóricos , Estados Unidos
14.
J Dairy Sci ; 101(7): 6443-6454, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29705432

RESUMEN

This paper uses an agent-based simulation model to estimate the costs associated with Mycobacterium avium ssp. paratuberculosis (MAP), or Johne's disease, in a milking herd, and to determine the net benefits of implementing various control strategies. The net present value (NPV) of a 1,000-cow milking herd is calculated over 20 yr, parametrized to a representative US commercial herd. The revenues of the herd are generated from sales of milk and culled animals. The costs include all variable and fixed costs necessary to operate a representative 1,000-cow milking herd. We estimate the NPV of the herd with no MAP infection, under an expected endemic infection distribution with no controls, and under an expected endemic infection distribution with various controls. The initial number of cows in a herd with an endemic MAP infection is distributed as 75% susceptible, 13% latent, 9% low MAP shedding, and 3% high MAP shedding. Control strategies include testing using ELISA and fecal culture tests and culling of cows that test positive, and culling based on observable milk production decrease. Results show that culling cows based on test results does not increase the herd's NPV and in most cases decreases NPV due to test costs as well as false positives and negatives with their associated costs (e.g., culling healthy cows and keeping infected cows). Culling consistently low producing cows when MAP is believed to be present in the herd produces higher NPV over the strategy of testing and culling MAP infected animals, and over the case of no MAP control.


Asunto(s)
Enfermedades de los Bovinos/economía , Industria Lechera/economía , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/economía , Animales , Bovinos , Enfermedades de los Bovinos/prevención & control , Análisis Costo-Beneficio , Industria Lechera/métodos , Ensayo de Inmunoadsorción Enzimática , Heces , Femenino , Leche , Paratuberculosis/prevención & control
15.
Nephrology (Carlton) ; 22(4): 301-307, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27003709

RESUMEN

AIM: As one of the most popular social networking sites in the world, Facebook has strong potential to enable peer support and the user-driven sharing of health information. We carried out a qualitative thematic analysis of the wall posts of a public Facebook group focused on dialysis to identify some of the major themes discussed. METHODS: We searched Facebook using the word 'dialysis'. A Facebook group (Dialysis Discussion Uncensored) with the highest number of members was selected amongst publicly available forums related to dialysis and operated in English (http://www.facebook.com/groups/DialysisUncensored). Two researchers independently extracted information on features of the group including purpose, group members and the user-generated posts on the group wall. Posts were further analysed to develop major themes. RESULTS: Characteristics of a Facebook group based on its participants and activities are presented. Three themes are described with representative quotations. In a period of 2 weeks, we found 1257 wall posts with total of 31 636 likes and 15 972 comments. All messages were in English, and the majority of the participants were dialysis patients. However, we observed the participation of family members and care providers as well. Posts were categorized into three major themes: sharing information, seeking and providing emotional and social support and sharing experience. CONCLUSION: Findings of this study provide an example of how a social networking platform can enable patients and their families to share information and to encourage peer-based support for managing dialysis-related experiences.


Asunto(s)
Cuidadores/psicología , Familia/psicología , Conocimientos, Actitudes y Práctica en Salud , Enfermedades Renales/terapia , Pacientes/psicología , Diálisis Renal , Red Social , Acceso a la Información , Adaptación Psicológica , Actitud del Personal de Salud , Comunicación , Costo de Enfermedad , Emociones , Relaciones Familiares , Humanos , Difusión de la Información , Enfermedades Renales/fisiopatología , Enfermedades Renales/psicología , Grupo Paritario , Investigación Cualitativa , Apoyo Social
16.
Small ; 12(21): 2866-71, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27087475

RESUMEN

A strongly coupled CoCr2 O4 /carbon nanosheet composite is concurrently grown via a facile one-step molten-salt calcination approach. The strong coupling between carbon and CoCr2 O4 has improved the electrical conductivity and preserved the active sites in catalysts. These results may pave the way to improve the performance of spinel oxides as electrocatalysts for oxygen evolution reactions.

17.
J Theor Biol ; 408: 105-117, 2016 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-27521525

RESUMEN

In the dairy industry, Johne's disease (JD), caused by Mycobacterium avium subsp. paratuberculosis (MAP) is one of the major investigated diseases. To date, researchers have suggested some control strategies for JD, such as test-and-cull based herd management, isolated calf rearing management, and vaccinations. Due to the slow progressing nature of MAP, tests with low diagnostic test sensitivity and specificity, and economic limitations, implementing these strategies has not resulted in elimination of MAP from farms. To date, no study has integrated detailed dairy herd dynamics with different MAP transmission routes. We have developed an individual-based dairy herd model by incorporating basic herd dynamics in a closed herd environment where no new animals have been bought from outside. The model considered three age groups of animals: calves, heifers and adults. It includes sequential life events of a dairy animal and such key dynamic processes of the dairy herd as lactation cycle, calving, voluntary waiting period, insemination, pregnancy, dry-off period and calf and heifer rearing. After initially validating that the model reproduced typical herd dynamics, it was extended by incorporating MAP infection dynamics, where each individual adult animal belonged to one of four infection compartments: susceptible, latent, low shedding and high shedding. The model includes two disease transmission routes: horizontal transmission (i.e., fecal-oral) and vertical transmission (i.e., in utero infection). The results confirm that this model can simulate a realistic dairy herd and that inclusion of the above-mentioned dynamic processes provides useful information about individual infected animals to farmers. Access to the individual animal information offers more validity to assessment of appropriate control strategies for an endemically MAP infected herd. This model can serve as an accurate and novel tool not only to better understand MAP dynamics, but is also valuable as an individual based system of a typical dairy herd that can be applied to other research questions.


Asunto(s)
Modelos Biológicos , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/transmisión , Animales , Bovinos , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/transmisión , Industria Lechera , Paratuberculosis/prevención & control , Dinámica Poblacional
18.
Clin Exp Nephrol ; 20(3): 379-93, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26728745

RESUMEN

The growing burden of chronic kidney disease (CKD), with its associated morbidity and mortality, is recognized as a major public health problem globally and causing substantial load on health care systems. The current framework for the definition and staging of CKD, based on eGFR levels or presence of kidney damage, is useful for clinical classification of patients, but identifies a huge number of people as having CKD which is too many to target for intervention. The ability to identify a subset of patients, at high risk for adverse outcomes, would be useful to inform clinical management. The current staging system applies static definitions of kidney function that fail to capture the dynamic nature of the kidney disease over time. Now-a-days, it is possible to capture multiple measurements of different laboratory test results for an individual including eGFR values. A new possibility for identifying individuals at higher risk of adverse outcomes is being explored through assessment and consideration of the rate of change in kidney function over time, and this approach will be feasible in the current context of digitalization of health record keeping system. On the basis of the existing evidence, this paper summarizes important findings that support the concept of dynamic changes in kidney function over time, and discusses how the magnitude of these changes affect the future adverse outcomes of kidney disease, particularly the End Stage Renal Disease (ESRD), CVD and mortality.


Asunto(s)
Tasa de Filtración Glomerular , Riñón/fisiopatología , Insuficiencia Renal Crónica/fisiopatología , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/fisiopatología , Progresión de la Enfermedad , Humanos , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/fisiopatología , Selección de Paciente , Valor Predictivo de las Pruebas , Pronóstico , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/terapia , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
19.
Prev Chronic Dis ; 12: E11, 2015 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-25633486

RESUMEN

INTRODUCTION: We studied Facebook groups related to hypertension to characterize their objectives, subject matter, member sizes, geographical boundaries, level of activity, and user-generated content. METHODS: We performed a systematic search among open Facebook groups using the keywords "hypertension," "high blood pressure," "raised blood pressure," and "blood pressure." We extracted relevant data from each group's content and developed a coding and categorizing scheme for the whole data set. Stepwise logistic regression was used to explore factors independently associated with each group's level of activity. RESULTS: We found 187 hypertension-related Facebook groups containing 8,966 members. The main objective of most (59.9%) Facebook groups was to create hypertension awareness, and 11.2% were created primarily to support patients and caregivers. Among the top-displayed, most recent posts (n = 164), 21.3% were focused on product or service promotion, whereas one-fifth of posts were related to hypertension-awareness information. Each Facebook group's level of activity was independently associated with group size (adjusted odds ratio [AOR], 1.02; 95% confidence interval [CI], 1.01-1.03), presence of "likes" on the most recent wall post (AOR, 3.55, 95% CI, 1.41-8.92), and presence of attached files on the group wall (AOR, 5.01, 95% CI, 1.25-20.1). CONCLUSION: The primary objective of most of the hypertension-related Facebook groups observed in this study was awareness creation. Compared with the whole Facebook community, the total number of hypertension-related Facebook groups and their users was small and the groups were less active.


Asunto(s)
Promoción de la Salud , Hipertensión/diagnóstico , Difusión de la Información/métodos , Educación del Paciente como Asunto/métodos , Medios de Comunicación Sociales/provisión & distribución , Red Social , Apoyo Social , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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