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1.
iScience ; 27(4): 109416, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38510142

RESUMEN

Battery health assessment and recuperation play crucial roles in the utilization of second-life Li-ion batteries. However, due to ambiguous aging mechanisms, it is challenging to estimate battery health and devise an effective strategy for cell rejuvenation. This paper presents aging and reconditioning experiments of 62 commercial lithium iron phosphate cells, which allow us to use machine learning models to predict cycle life and identify important indicators of recoverable capacity. An average test error of 16.84% ± 1.87% (mean absolute percentage error) for cycle life prediction is achieved by gradient boosting regressor. Some of the recoverable lost capacity is found to be attributed to the non-uniformity in electrodes. An experimentally validated equivalent circuit model is built to demonstrate how such non-uniformity can be accumulated, and how it can give rise to recoverable capacity loss. Furthermore, Shapley additive explanations (SHAP) analysis also reveals that battery operation history significantly affects the capacity recovery.

2.
Curr Oncol ; 30(9): 8078-8091, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37754501

RESUMEN

BACKGROUND: The successful implementation of an equitable lung cancer screening program requires consideration of factors that influence accessibility to screening services. METHODS: Using lung cancer cases in British Columbia (BC), Canada, as a proxy for a screen-eligible population, spatial access to 36 screening sites was examined using geospatial mapping and vehicle travel time from residential postal code at diagnosis to the nearest site. The impact of urbanization and Statistics Canada's Canadian Index of Multiple Deprivation were examined. RESULTS: Median travel time to the nearest screening site was 11.7 min (interquartile range 6.2-23.2 min). Urbanization was significantly associated with shorter drive time (p < 0.001). Ninety-nine percent of patients with ≥60 min drive times lived in rural areas. Drive times were associated with sex, ethnocultural composition, situational vulnerability, economic dependency, and residential instability. For example, the percentage of cases with drive times ≥60 min among the least deprived situational vulnerability group was 4.7% versus 44.4% in the most deprived group. CONCLUSIONS: Populations at risk in rural and remote regions may face more challenges accessing screening services due to increased travel times. Drive times increased with increasing sociodemographic and economic deprivations highlighting groups that may require support to ensure equitable access to lung cancer screening.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Colombia Británica
3.
Sci Adv ; 8(19): eabm2422, 2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35544561

RESUMEN

A reliable energy storage ecosystem is imperative for a renewable energy future, and continued research is needed to develop promising rechargeable battery chemistries. To this end, better theoretical and experimental understanding of electrochemical mechanisms and structure-property relationships will allow us to accelerate the development of safer batteries with higher energy densities and longer lifetimes. This Review discusses the interplay between theory and experiment in battery materials research, enabling us to not only uncover hitherto unknown mechanisms but also rationally design more promising electrode and electrolyte materials. We examine specific case studies of theory-guided experimental design in lithium-ion, lithium-metal, sodium-metal, and all-solid-state batteries. We also offer insights into how this framework can be extended to multivalent batteries. To close the loop, we outline recent efforts in coupling machine learning with high-throughput computations and experiments. Last, recommendations for effective collaboration between theorists and experimentalists are provided.

4.
Phys Rev E ; 100(4-1): 042204, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31770935

RESUMEN

An immobile charged species provides a charged medium for transport of charge carriers that is exploited in many applications, such as permselective membranes, doped semiconductors, biological ion channels, as well as porous media and microchannels with surface charges. In this paper, we theoretically study the electrochemical impedance of electrodiffusion in a charged medium by employing the Nernst-Planck equation and the electroneutrality condition with a background charge density. The impedance response is obtained under different dc bias conditions extending above the diffusion-limiting bias. We find a transition in the impedance behavior around the diffusion-limiting bias and present an analytical approximation for a weakly charged medium under an overlimiting bias.

5.
BMC Cancer ; 19(1): 543, 2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31170936

RESUMEN

BACKGROUND: Iron has been shown to promote breast carcinogenesis in animal models through generation of oxidative stress and interaction with estrogen. Heme iron, which is found exclusively in animal-sourced foods, is suggested to have a more detrimental effect. Epidemiological evidence of the association between iron and breast cancer risk remains inconclusive and has not been comprehensively summarized. This systematic review and meta-analysis evaluated associations between both iron intake and body iron status and breast cancer risk. METHODS: Four electronic databases (MEDLINE, EMBASE, CINAHL, and Scopus) were searched up to December 2018 for studies assessing iron intake and/or biomarkers of iron status in relation to breast cancer risk. Using random-effects meta-analyses, pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated comparing the highest vs. lowest category of each iron measure. Dose-response meta-analyses were also performed to investigate linear and nonlinear associations. RESULTS: A total of 27 studies were included in the review, of which 23 were eligible for meta-analysis of one or more iron intake/status measures. Comparing the highest vs. lowest category, heme iron intake was significantly associated with increased breast cancer risk, with a pooled RR of 1.12 (95% CI: 1.04-1.22), whereas no associations were found for dietary (1.01, 95% CI: 0.89-1.15), supplemental (1.02, 95% CI: 0.91-1.13), or total (0.97, 95% CI: 0.82-1.14) iron intake. Associations of iron status indicators with breast cancer risk were generally in the positive direction; however, a significant pooled RR was found only for serum/plasma levels (highest vs. lowest) of iron (1.22, 95% CI: 1.01-1.47), but not for ferritin (1.13, 95% CI: 0.78-1.62), transferrin saturation (1.16, 95% CI: 0.91-1.47), or total iron-binding capacity (1.10, 95% CI: 0.97-1.25). In addition, a nonlinear dose-response was observed for heme iron intake and serum iron (both Pnonlinearity < 0.05). CONCLUSIONS: Heme iron intake and serum iron levels may be positively associated with breast cancer risk. Although associations were modest, these findings may have public health implications given the widespread consumption of (heme) iron-rich foods. In light of methodological and research gaps identified, further research is warranted to better elucidate the relationship between iron and breast cancer risk.


Asunto(s)
Neoplasias de la Mama/patología , Hierro de la Dieta , Hierro/sangre , Estado Nutricional/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/etiología , Carcinogénesis/metabolismo , Femenino , Ferritinas/sangre , Hemo/química , Humanos , Carne/efectos adversos , Persona de Mediana Edad , Posmenopausia , Riesgo , Transferrina/análisis , Adulto Joven
6.
Zoonoses Public Health ; 66(4): 428-435, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30665259

RESUMEN

The objective of this study was to determine healthcare costs attributable to laboratory-confirmed Lyme disease (LD) from the healthcare payer perspective in Ontario, Canada. A cost-of-illness study was conducted for incident LD subjects from 1 January 2006 through 31 December 2013 ascertained from provincial laboratory and reportable disease databases, linked to health administrative data. All LD subjects included were laboratory-confirmed, according to provincial case definitions. Incident LD subjects were propensity-score matched to uninfected subjects on age, sex, comorbidities and urban/rural status. We used phase-of-care methods to calculate attributable costs for two phases of illness: initial care (≤30 days following "index date") and continuing care (>30 days after index date to the end of the follow-up period). A total of 663 incident, confirmed LD subjects were identified from 2006 through 2013. Mean age was 44.2 ± 20.1 years; 339 (51.1%) were female; and 31 (4.7%) were hospitalized ≤30 days after index date. Six hundred fifty-eight (99.2%) LD subjects were matched to uninfected subjects; mean follow-up time was 3.3 years. Mean attributable costs per case during the initial care phase and continuing care were $277 (95% CI: $197, $357) and -$5 (-$27, $17), respectively. Attributable costs per LD subject aged 5-14 years were $440 ($132, $747), greater than the costs observed for other age strata. Expected 1-year attributable costs were $832, given continuing care costs were negligible. Limitations to our study include estimating costs using a cohort of only laboratory-confirmed LD cases, introducing selection bias for diagnosed and treated patients who may have a lower risk of developing sequelae. In conclusion, the initial care phase of LD is associated with increased healthcare costs, but without significant costs attributable to LD infection after 30 days. Estimates of costs attributable to LD are important for healthcare resource prioritization and the evaluation of novel interventions.


Asunto(s)
Costos de la Atención en Salud/estadística & datos numéricos , Enfermedad de Lyme/economía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Preescolar , Técnicas de Laboratorio Clínico , Estudios de Cohortes , Costo de Enfermedad , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ontario , Proyectos de Investigación , Adulto Joven
7.
Can J Public Health ; 109(4): 451-458, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30276636

RESUMEN

OBJECTIVE: For patients who belonged to physician rosters at a family medicine practice in the core of Calgary, Canada, we compared primary care utilization for those who were stably housed and those experiencing homelessness. METHODS: This retrospective chart review accessed electronic medical record data for rostered patients who visited their family physician between July 1, 2015 and August 31, 2016. We assessed the association between homelessness status (defined as having been sheltered in overnight shelters and/or emergency/provisional housing during the study period) and the rate of visits to primary care (defined as the count of visits associated with a patient accounting for the length of the patient's relationship with their family physician) using multivariate negative binomial regression. RESULTS: We analyzed 1013 patients belonging to three family physician rosters, of whom 112 experienced homelessness during the study period (11.1%). The mean number of visits for patients who experienced homelessness was 9.6 (SD 10.5), compared to 4.2 (SD 3.6) visits for stably housed patients (p < 0.0001). The rate of accessing primary care for patients experiencing homelessness was 2.02 times greater than the rate for stably housed individuals (rate ratio [RR] 2.02, 95% confidence interval [95% CI] 1.74-2.35; p < 0.0001). CONCLUSION: In the context of an inner-city primary care clinic in Calgary, Canada, homelessness status is associated with an increased rate of visits to primary care. This work has implications for public health and health systems decision-makers involved in developing equitable health policy, as well as for frontline care providers who serve this vulnerable population.


Asunto(s)
Personas con Mala Vivienda/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Atención Primaria de Salud/estadística & datos numéricos , Adulto , Canadá , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Estudios Retrospectivos
8.
PLoS One ; 11(4): e0153852, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27100392

RESUMEN

BACKGROUND: Mutations in granulin (PGRN) and tau (MAPT), and hexanucleotide repeat expansions near the C9orf72 genes are the most prevalent genetic causes of frontotemporal lobar degeneration. Although behavior, language and movement presentations are common, the relationship between genetic subgroup and movement disorder phenomenology is unclear. OBJECTIVE: We conducted a systematic review and meta-analysis of the literature characterizing the spectrum and prevalence of movement disorders in genetic frontotemporal lobar degeneration. METHODS: Electronic databases were searched using terms related to frontotemporal lobar degeneration and movement disorders. Articles were included when cases had a proven genetic cause. Study-specific prevalence estimates for clinical features were transformed using Freeman-Tukey arcsine transformation, allowing for pooled estimates of prevalence to be generated using random-effects models. RESULTS: The mean age at onset was earlier in those with MAPT mutations compared to PGRN (p<0.001) and C9orf72 (p = 0.024). 66.5% of subjects had an initial non-movement presentation that was most likely a behavioral syndrome (35.7%). At any point during the disease, parkinsonism was the most common movement syndrome reported in 79.8% followed by progressive supranuclear palsy (PSPS) and corticobasal (CBS) syndromes in 12.2% and 10.7%, respectively. The prevalence of movement disorder as initial presentation was higher in MAPT subjects (35.8%) compared to PGRN subjects (10.1). In those with a non-movement presentation, language disorder was more common in PGRN subjects (18.7%) compared to MAPT subjects (5.4%). SUMMARY: This represents the first systematic review and meta-analysis of the occurrence of movement disorder phenomenology in genetic frontotemporal lobar degeneration. Standardized prospective collection of clinical information in conjunction with genetic characterization will be crucial for accurate clinico-genetic correlation.


Asunto(s)
Degeneración Lobar Frontotemporal/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Trastornos del Movimiento/etiología , Mutación/genética , Proteínas tau/genética , Edad de Inicio , Degeneración Lobar Frontotemporal/complicaciones , Degeneración Lobar Frontotemporal/patología , Humanos , Trastornos del Movimiento/patología , Progranulinas
9.
Respirology ; 21(6): 1015-25, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27009804

RESUMEN

Nontuberculous mycobacterial (NTM) infections are increasing in disease frequency worldwide. This systematic review examines health-related quality of life (HRQOL), comorbidities and mortality associated with pulmonary NTM disease. We searched MEDLINE, EMBASE, CINAHL, Scopus Life Sciences, conference proceedings and Google (earliest date available to February 2015) for primary studies. Eligible studies compared populations with and without pulmonary NTM disease in high-income jurisdictions. We excluded studies on HIV/AIDS. All languages were accepted. Two reviewers followed MOOSE and PRISMA reporting guidelines and independently appraised quality using STROBE. All studies were summarized qualitatively regardless of quality. Of 3193 citations screened, we included 17 studies mostly from Taiwan (n = 5) and the USA (n = 4). Two studies assessed HRQOL; one assessed comorbidities, 11 assessed mortality, and three assessed multiple outcomes. Populations with pulmonary NTM reported significantly worse or similar HRQOL than the general population, depending on the instruments used. Some suggested greater prevalence of having bronchiectasis (n = 2) and greater risk of developing pulmonary tuberculosis (n = 1). Most (n = 7) suggested no difference in mortality, although only one was age-matched and gender-matched to the general population. Four suggested NTM populations had higher mortality-two of which compared with the general population and were deemed of high quality, while two compared with non-NTM patients from hospital. High clinical heterogeneity in study design may explain discordant results. Bias assessments and controlling for confounding were carried out poorly. No consistent trends were observed although there is suggestion of an increased health burden from respiratory diseases and increased mortality associated with pulmonary NTM disease.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Calidad de Vida , Tuberculosis Pulmonar/epidemiología , Adulto , Bronquiectasia/epidemiología , Comorbilidad , Costo de Enfermedad , Femenino , Humanos , Masculino , Mortalidad , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/psicología , Prevalencia , Adulto Joven
10.
CMAJ Open ; 3(2): E208-16, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26389099

RESUMEN

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) is increasing and survival rates are poor. Our objectives were to estimate the relative survival over time in patients with HCC in Ontario and to examine potential factors associated with excess mortality risk. METHODS: We performed a population-based retrospective cohort analysis involving patients with a diagnosis of HCC in Ontario between 1990 and 2009 using data extracted from the Ontario Cancer Registry. Relative survival was estimated by controlling for background mortality using expected mortality from Ontario life tables. A generalized linear model was used to estimate the excess mortality risk for important factors. RESULTS: A total of 5645 patients had HCC diagnosed during the study period; 4412 (78.2%) of these patients were male. Improvements in 1-year relative survival were observed across all age groups over time: the highest was among those patients less than 60 years of age who had a diagnosis of HCC during 2005-2009, with 1-year survival exceeding 50% for both sexes. However, the overall 5-year relative survival did not exceed 28%. The excess mortality risk decreased with increased years of follow-up, recent diagnosis, and curative or noncurative treatments for HCC, whereas excess mortality risk increased with age. INTERPRETATION: Although improving, the prognosis for HCC remains poor. Our findings highlight the importance of effective prevention and treatment for HCC to reduce the burden of disease and improve health care systems.

11.
PLoS One ; 9(12): e114733, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25536218

RESUMEN

OBJECTIVE: Evaluate safety and efficacy of Incobotulinumtoxin A in elderly patients with dementia and paratonia. SETTING: University-affiliated hospital, spasticity management Clinic. PARTICIPANTS: Ten subjects were enrolled. INCLUSION CRITERIA: 1) severe cognitive impairment 2) diagnosis of Alzheimer's disease, vascular dementia, or frontotemporal dementia, and 3) score >3 on the paratonic assessment instrument, with posture in an arm(s) interfering with provision of care. EXCLUSION CRITERIA: 1) alternate etiologies for increased tone and 2) injection with botulinum toxin within the 6 months preceding the study. DESIGN: Single center, randomized, double blind, placebo-controlled, crossover trial with two treatment cycles of 16 weeks. Assessments occurred at 2, 6, 12 and16 weeks following injections. Subjects received up to 300 U of Incobotulinumtoxin A in arm(s). PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome measure was the modified caregiver burden scale (mCBS); exploratory secondary outcome measures were also performed. Analysis of variance and mixed modeling techniques were used to evaluate treatment effects. RESULTS: Incobotulinumtoxin A treatment produced significant improvement in mCBS total score -1.11 (-2.04 to -0.18) (Treatment effect and 95% CI), dressing sub-score -0.36 (-0.59 to 0.12), and cleaning under the left and right armpits sub-score -0.5 (-0.96 to -0.04), -0.41 (-0.79 to -0.04) respectively. PROM in the left and right elbow increased by 27.67 degrees (13.32-42.02) and 22.07 degrees (9.76-34.39) respectively. PROM in the left and right shoulder increased by 11.92 degrees (5.46-18.38) and 8.58 degrees (3.73-13.43) respectively. No significant treatment effect was found for GAS, VAS and PAINAD scales or change in time to perform care. No adverse drug reactions occurred. CONCLUSIONS: Administration of Incobotulinumtoxin A in elderly people with advanced dementia and paratonia may be an efficacious and safe treatment to increase range of motion and reduce functional burden. Further studies are needed to confirm results. TRIAL REGISTRATION: ClinicalTrials.Gov NCT02212119.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/tratamiento farmacológico , Rigidez Muscular/complicaciones , Rigidez Muscular/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/farmacología , Demografía , Femenino , Humanos , Masculino , Modelos Biológicos , Proyectos Piloto , Placebos , Rango del Movimiento Articular/efectos de los fármacos , Reproducibilidad de los Resultados , Escala Visual Analógica
12.
Sci Rep ; 4: 7056, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25394685

RESUMEN

Understanding over-limiting current (faster than diffusion) is a long-standing challenge in electrochemistry with applications in desalination and energy storage. Known mechanisms involve either chemical or hydrodynamic instabilities in unconfined electrolytes. Here, it is shown that over-limiting current can be sustained by surface conduction in nanopores, without any such instabilities, and used to control dendritic growth during electrodeposition. Copper electrodeposits are grown in anodized aluminum oxide membranes with polyelectrolyte coatings to modify the surface charge. At low currents, uniform electroplating occurs, unaffected by surface modification due to thin electric double layers, but the morphology changes dramatically above the limiting current. With negative surface charge, growth is enhanced along the nanopore surfaces, forming surface dendrites and nanotubes behind a deionization shock. With positive surface charge, dendrites avoid the surfaces and are either guided along the nanopore centers or blocked from penetrating the membrane.

13.
PLoS Curr ; 62014 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-25642358

RESUMEN

The 2014 West African Ebola virus outbreak, now more correctly referred to as an epidemic, is the largest ever to occur. As of August 28, 2014, concerns have been raised that control efforts, particularly in Liberia, have been ineffective, as reported case counts continue to increase. Limited data are available on the epidemiology of the outbreak. However, reported cumulative incidence data as well as death counts are available for Guinea, Sierra Leone, Liberia and Nigeria. We utilized a simple, two parameter mathematical model of epidemic growth and control, to characterize epidemic growth patterns in West Africa, to evaluate the degree to which the epidemic is being controlled, and to assess the potential implications of growth patterns for epidemic size. Models demonstrated good fits to data. Overall basic reproductive number (R0) for the epidemic was estimated to be between 1.6 and 2.0, consistent with prior outbreaks. However, we identified only weak evidence for the occurrence of epidemic control in West Africa as a whole, and essentially no evidence for control in Liberia (though slowing of growth was seen in Guinea and Sierra Leone). It is projected that small reductions in transmission would prevent tens of thousands of future infections. These findings suggest that there is an extraordinary need for improved control measures for the 2014 Ebola epidemic, especially in Liberia, if catastrophe is to be averted.

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