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1.
Sci Rep ; 14(1): 7231, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538681

RESUMEN

Generally, when optimizing a rolling stock schedule, the locations of the depots, or places in the network where the composition changes and maintenance occurs, are assumed known. The locations where maintenance is performed naturally influence the quality of any resulting rolling stock schedules. In this paper, the problem of selecting new depot locations and their corresponding capacities is considered. A two-stage mixed integer programming approach for rolling stock scheduling with maintenance requirements is extended to account for depot selection. First, a conventional flow-based model is solved, ignoring maintenance requirements, to obtain a variety of rolling stock schedules with multiple depot locations and capacity options. Then, a maintenance feasible rolling stock schedule can be obtained by solving a series of assignment problems by using the schedules found in the first stage. The proposed methodology is tested on real-life instances, and the numerical experiments of different operational scenarios are discussed.

2.
Sensors (Basel) ; 23(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37447659

RESUMEN

Erasure-code-based storage systems suffer from problems such as long repair time and low I/O performance, resulting in high repair costs. For many years, researchers have focused on reducing the cost of repairing erasure-code-based storage systems. In this study, we discuss the demerits of node selecting, data transferring and data repair in erasure-code-based storage systems. Based on the network topology and node structure, we propose SDNC-Repair, a cooperative data repair strategy based on erasure code for SDS (Software Defined Storage), and describe its framework. Then, we propose a data source selection algorithm that senses the available network bandwidth between nodes and a data flow scheduling algorithm in SDNC-Repair. Additionally, we propose a data repair method based on node collaboration and data aggregation. Experiments illustrate that the proposed method has better repair performance under different data granularities. Compared to the conventional repair method, although the SDNC-Repair is more constrained by the cross-rack bandwidth, it improves system throughput effectively and significantly reduces data repair time in scenarios where multiple nodes fail and bandwidth is limited.


Asunto(s)
Algoritmos , Programas Informáticos
3.
Clin Lab ; 69(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37057937

RESUMEN

BACKGROUND: Only a few epidemiological studies have reported the association between blood selenium and the prevalence of anemia. To date, the evidence is limited and inconsistent. METHODS: We enrolled 9,335 participants (≥ 20 years) who participated in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2016 to assess the link between blood selenium and the risk of anemia. Multivariate logistic regression analysis and a generalized additive model (GAM) was applied to assess the relationship between blood selenium and anemia risk. RESULTS: We found a significant adverse association between blood selenium and the prevalence of anemia after adjusting for all potential covariates (OR = 0.98, 95% CI: 0.97, 0.98, p < 0.001). After a sequence of sensitive analyses, the conclusion remains stable (p for trend < 0.001). However, a non-linear relationship was detected based on GAM. We calculated a turning point of 205.89 µg/L using a two-piecewise linear regression model. CONCLUSIONS: When blood selenium level is lower than 205.89 µg/L, blood selenium level is inversely associated with the risk of anemia. Our results provide a new strategy to reduce the risk of anemia.


Asunto(s)
Anemia , Selenio , Humanos , Adulto , Encuestas Nutricionales , Anemia/epidemiología , Prevalencia , Modelos Lineales
4.
PLoS One ; 18(2): e0281950, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36848383

RESUMEN

As the COVID-19 pandemic fades, the aviation industry is entering a fast recovery period. To analyze airport networks' post-pandemic resilience during the recovery process, this paper proposes a Comprehensive Resilience Assessment (CRA) model approach using the airport networks of China, Europe, and the U.S.A as case studies. The impact of COVID-19 on the networks is analyzed after populating the models of these networks with real air traffic data. The results suggest that the pandemic has caused damage to all three networks, although the damages to the network structures of Europe and the U.S.A are more severe than the damage in China. The analysis suggests that China, as the airport network with less network performance change, has a more stable level of resilience. The analysis also shows that the different levels of stringency policy in prevention and control measures during the epidemic directly affected the recovery rate of the network. This paper provides new insights into the impact of the pandemic on airport network resilience.


Asunto(s)
Aviación , COVID-19 , Humanos , Aeropuertos , Pandemias/prevención & control , COVID-19/epidemiología , COVID-19/prevención & control , Políticas
5.
Clin Chem ; 69(4): 374-385, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36702572

RESUMEN

BACKGROUND: The role of sex hormone-binding globulin (SHBG) levels in clinical risk stratification and intervention for coronary heart disease (CHD) remains uncertain. We aimed to examine whether circulating levels of SHBG are predictive of CHD risk in men and women. METHODS: We investigated the association between SHBG and the risk of incident CHD in 128 322 men and 135 103 women free of CHD at baseline in the prospective United Kingdom Biobank (UKB) cohort. The unconfounded associations were estimated using Mendelian randomization (MR) analysis. We further conducted a meta-analysis to integrate currently available prospective evidence. CHD events included nonfatal and fatal myocardial infarction and coronary revascularization. RESULTS: In the UKB, during a median of 11.7 follow-up years, 10 405 men and 4512 women developed CHD. Serum levels of SHBG were monotonically associated with a decreased risk of CHD in both men (adjusted hazard ratio [HR] per log nmol/L increase in SHBG: 0.88 [0.83-0.94]) and women (HR: 0.89 [0.83-0.96]). MR-based analyses suggested causality and a dose-response relationship of SHBG with CHD risk. A cumulative meta-analysis including 216 417 men and 138 282 women from 11 studies showed that higher levels of SHBG were prospectively associated with decreased CHD risk in men comparing the highest with the lowest quartile: pooled relative risk (RR) 0.81 (0.74-0.89) and women (pooled RR: 0.86 [0.78-0.94]). CONCLUSIONS: Higher circulating SHBG levels were directly and independently predictive of lower CHD risk in both men and women. The utility of SHBG for CHD risk stratification and prediction warrants further study.


Asunto(s)
Enfermedad Coronaria , Infarto del Miocardio , Humanos , Estudios Prospectivos , Globulina de Unión a Hormona Sexual/análisis , Riesgo , Factores de Riesgo
6.
Public Health Nutr ; 24(15): 5081-5089, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33634772

RESUMEN

OBJECTIVE: Previous studies have reported inverse associations between certain healthy lifestyle factors and non-alcoholic fatty liver disease (NAFLD), but limited evidence showed the synergistic effect of those lifestyles. This study examined the relationship of a combination of lifestyles, expressed as Healthy Lifestyle Score (HLS), with NAFLD. DESIGN: A community-based cross-sectional study. Questionnaires and body assessments were used to collect data on the six-item HLS (ranging from 0 to 6, where higher scores indicate better health). The HLS consists of non-smoking (no active or passive smoking), normal BMI (18·5-23·9 kg/m2), physical activity (moderate or vigorous physical activity ≥ 150 min/week), healthy diet pattern, good sleep (no insomnia or <6 months) and no anxiety (Self-rating Anxiety Scale < 50), one point each. NAFLD was diagnosed by ultrasonography. SETTING: Guangzhou, China. PARTICIPANTS: Two thousand nine hundred and eighty-one participants aged 40-75 years. RESULTS: The overall prevalence of NAFLD was 50·8 %. After adjusting for potential covariates, HLS was associated with lower presence of NAFLD. The OR of NAFLD for subjects with higher HLS (3, 4, 5-6 v. 0-1 points) were 0·68 (95 % CI 0·51, 0·91), 0·58 (95 % CI 0·43, 0·78) and 0·35 (95 % CI 0·25, 0·51), respectively (P-values < 0·05). Among the six items, BMI and physical activity were the strongest contributors. Sensitivity analyses showed that the association was more significant after weighting the HLS. The beneficial association remained after excluding any one of the six components or replacing BMI with waist circumference. CONCLUSIONS: Higher HLS was associated with lower presence of NAFLD, suggesting that a healthy lifestyle pattern might be beneficial to liver health.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Adulto , Anciano , China/epidemiología , Estudios Transversales , Estilo de Vida Saludable , Humanos , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Factores de Riesgo , Circunferencia de la Cintura
7.
Br J Nutr ; 125(4): 460-470, 2021 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-32713378

RESUMEN

Flavonoid-rich foods have shown a beneficial effect against non-alcoholic fatty liver disease (NAFLD) in short-term randomised trials. It is uncertain whether the usual dietary intake of flavonoids may benefit patients with NAFLD. The present study evaluated the association between the usual intake of flavonoids and the risk of progression in NAFLD. The prospective study included 2694 adults from the Guangzhou Nutrition and Health Study. Face-to-face interviews using a seventy-nine-item FFQ were administered to assess habitual dietary flavonoid intake, while abdominal ultrasonography was conducted to evaluate the presence and degree of NAFLD, with measurements conducted 3 years apart. After adjustment for potential confounders, higher flavonoid intakes were gradely associated with reduced risks of worsen NAFLD status. The relative risks of worsening (v. non-worsening) NAFLD in the highest (v. lowest) quintile were 0·71 (95 % CI 0·54, 0·93) for total flavonoids, 0·74 (95 % CI 0·57, 0·95) for flavanones, 0·74 (95 % CI 0·56, 0·96) for flavan-3-ols, 0·90 (95 % CI 0·68, 1·18) for flavonols, 0·73 (95 % CI 0·56, 0·93) for flavones, 0·79 (95 % CI 0·61, 1·02) for isoflavones and 0·74 (95 % CI 0·57, 0·96) for anthocyanins. An L-shaped relationship was observed between total flavonoid intake and the risk of NAFLD progression. Path analyses showed that the association between flavonoids and NAFLD progression was mediated by decreases in serum cholesterol and homeostasis model assessment of insulin resistance. This prospective study showed that higher flavonoid intake was associated with a lower risk of NAFLD progression in the elderly overweight/obese Chinese population.


Asunto(s)
Dieta , Flavonoides/administración & dosificación , Análisis de los Alimentos , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Abdomen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Estudios Prospectivos , Ultrasonografía
8.
Atherosclerosis ; 298: 7-13, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32126389

RESUMEN

BACKGROUND AND AIMS: The relationship of polyunsaturated fatty acids (PUFAs) with cardiovascular risk is still controversial. We aimed to determine whether erythrocyte n-3 and n-6 PUFAs are related to the risk of carotid atherosclerosis. METHODS: From 2008 to 2019, baseline erythrocyte n-3 and n-6 PUFAs were determined in a cohort of 4040 Chinese adults (40-75 ys). The intima-media thickness (IMT) at the common carotid artery (CCA) and bifurcation of the carotid artery (BIF) and carotid plaque were assessed using ultrasonography at baseline and every 3 years. RESULTS: During a median follow-up of 8.8 years, we identified the following newly diagnosed cases: 535 cases of CCAIMT thickening, 654 cases of BIFIMT thickening, and 850 cases of carotid plaque. Higher erythrocyte docosahexaenoic acid (DHA) and arachidonic acid (ARA) and lower gamma-linolenic acid (GLA) were associated with decreased risks of BIFIMT thickening. N-3 eicosatrienoic acid (ETrA), docosapentaenoic acid (DPA), and n-6 dodecylthioacetic acid (DTA) presented a significant beneficial association with carotid IMT thickening in the short-term (2.8 y) follow-up (all p trend <0.02), although the association was attenuated in the relatively long-term (8.8 y) follow-up. In addition, carotid plaque risk was found to be inversely associated with ETrA and DHA but positively associated with alpha-linolenic acid (ALA). N-6 linolenic acid (LA) and eicosadienoic acid (EDA) were not significantly associated with carotid atherosclerosis risk. CONCLUSIONS: Higher erythrocyte very-long-chain n-3 and n-6 PUFAs (especially DHA and ARA) and lower erythrocyte GLA are associated with lower carotid atherosclerosis risk, suggesting potential cardioprotective roles of very-long-chain PUFAs.


Asunto(s)
Enfermedades de las Arterias Carótidas/metabolismo , Membrana Eritrocítica/metabolismo , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6/metabolismo , Adulto , Anciano , Ácido Araquidónico/sangre , Grosor Intima-Media Carotídeo , Ácidos Docosahexaenoicos/sangre , Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/sangre , Ácidos Grasos Insaturados/sangre , Ácidos Grasos Insaturados/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ácido gammalinolénico/sangre
9.
Eur J Nutr ; 59(2): 719-728, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30953148

RESUMEN

PURPOSE: Many studies have examined the association of isoflavone intake with type 2 diabetes (T2D), and produced inconsistent results. Few studies, however, explored the association using objective biomarkers (particular for daidzein metabolite-equol) of isoflavones. We aimed to explore the association of urinary equol, daidzein and genistein concentrations with T2D and examine the mediating roles of high-sensitivity C-reactive protein (hsCRP) and retinol binding protein 4 (RBP4). METHODS: This prospective study included 2818 subjects. Urinary concentrations of equol, daidzein and genistein were measured by high-performance liquid chromatography-tandem mass spectrometry. The associations between urinary isoflavones and T2D incidence were evaluated by cox proportional hazards model. RESULTS: After adjustment for covariates, urinary equol except daidzein and genistein was inversely associated with T2D incidence. In comparison with the first tertile, multivariable adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for T2D incidence in the second and third tertile of equol concentration were 0.52 (0.37, 0.73) and 0.72 (0.53, 0.97), respectively. In stratified analyses by sex, the HR (95% CI) of men in the second vs. first tertile of equol was 0.29 (0.14, 0.58). Equivalent estimation in women was 0.67 (0.45, 1.01). Neither women nor men in the third tertile showed significant difference of T2D incidence compared with the first tertile. In path analyses, there was no evidence of mediating effects of hsCRP and RBP4 on the "equol-T2D" relationship. CONCLUSIONS: Urinary equol was favorably associated with a decreased T2D incidence in Chinese adults. The equol-T2D relationship might not be mediated by hsCRP and RBP4. TRIAL REGISTRATION: This study has been registered at http://www.clinicaltrials.gov as NCT03179657.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/orina , Equol/orina , Genisteína/orina , Isoflavonas/orina , Biomarcadores/orina , China/epidemiología , Cromatografía Líquida de Alta Presión , Equol/farmacología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Genisteína/farmacología , Humanos , Incidencia , Isoflavonas/farmacología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo
10.
Endocr J ; 67(3): 257-266, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-31748434

RESUMEN

Little is known about the association between equol and bioavailable testosterone (BT) in adults. In this study, we examined the associations of urinary equol concentrations with serum concentrations of total, bioavailable and free testosterone (FT), dehydroepiandrosterone sulfide (DHEAS), free androgen index (FAI) and sex hormone-binding globulin (SHBG). This cross-sectional study included 1,904 women with a mean age of 59.7 years. Urinary equol concentrations were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The serum androgenic indices and SHBG were also determined. Overall, urinary equol tended to be inversely associated with bioactive forms of androgenic indices (BT, FT or FAI) but not with total testosterone (TT) or DHEAS. Urinary equol was also positively associated with SHBG. In multi-covariate-adjusted analyses stratified by menopausal status, graded and inverse associations between urinary equol and bioactive forms of androgenic indices (BT, FT and FAI) were observed in postmenopausal women (all p-trends < 0.05), but not in premenopausal women. A significant positive association between urinary equol and SHBG was observed only in postmenopausal women. No significant associations were observed between urinary equol and TT or DHEAS in either group. A path analysis indicated that these associations of equol with androgens in postmenopausal women might be mediated by SHBG. In conclusion, urinary equol exhibited graded and inverse associations with BT or FT, but not TT in women. However, further longitudinal studies of human patients are needed to confirm these results and overcome the limitations of cross-sectional studies.


Asunto(s)
Andrógenos/sangre , Sulfato de Deshidroepiandrosterona/sangre , Equol/orina , Testosterona/sangre , Anciano , Biomarcadores/sangre , Cromatografía Líquida de Alta Presión , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia/metabolismo , Premenopausia/metabolismo , Globulina de Unión a Hormona Sexual/metabolismo , Espectrometría de Masas en Tándem
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