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1.
PeerJ Comput Sci ; 10: e1763, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38196963

RESUMEN

The manufacturing sector faces unprecedented challenges, including intense competition, a surge in product varieties, heightened customization demands, and shorter product life cycles. These challenges underscore the critical need to optimize manufacturing systems. Among the most enduring and complex challenges within this domain is production scheduling. In practical scenarios, setup time is whenever a machine transitions from processing one product to another. Job scheduling with setup times or associated costs has garnered significant attention in both manufacturing and service environments, prompting extensive research efforts. While previous studies on customer order scheduling primarily focused on orders or jobs to be processed across multiple machines, they often overlooked the crucial factor of setup time. This study addresses a sequence-dependent bi-criterion scheduling problem, incorporating order delivery considerations. The primary objective is to minimize the linear combination of the makespan and the sum of weighted completion times of each order. To tackle this intricate challenge, we propose pertinent dominance rules and a lower bound, which are integral components of a branch-and-bound methodology employed to obtain an exact solution. Additionally, we introduce a heuristic approach tailored to the problem's unique characteristics, along with three refined variants designed to yield high-quality approximate solutions. Subsequently, these three refined approaches serve as seeds to generate three distinct populations or chromosomes, each independently employed in a genetic algorithm to yield a robust approximate solution. Ultimately, we meticulously assess the efficacy of each proposed algorithm through comprehensive simulation trials.

2.
RSC Adv ; 12(41): 26514-26526, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36275145

RESUMEN

The Rashba effect is an essential phenomenon in asymmetrical ferroelectric materials with local dipole fields. Rashba spin splitting due to spin-orbit coupling in the asymmetrical 2D ferroelectricity MTe (M = Ge, Sn, Pb) has provided a promising arena for achieving an ultra-high power factor to improve their thermoelectric performance. Herein, we show that the hidden Rashba effect may exist in centrosymmetric rock-salt MTe because of the emerging macroscopic electric dipoles caused by the local Te off-centering distortion. Using first-principles calculations, we prove that Te off-centering causes a change in the atomic reciprocal displacement and induces a ferroelectric Rashba effect in rock-salt MTe. Further analyses of the energy evaluation, lattice vibration and chemical orbital confirm that the atomic off-centering behavior manipulates Rashba spin splitting and stereochemical irregularities of the s2 lone electron pair of the cation, leading to the formation of strong anharmonic bonds in the original high-symmetry crystalline solids. The changes of the phonon dispersion and electronic structure also affect the electron-phonon scattering and scattering mechanism of MTe, which then manipulates the electrical transport properties. This work unravels the underlying physics on how the local Te off-centering distortion manipulates Rashba spin splitting and improves the thermoelectric performance of MTe.

3.
Nanomaterials (Basel) ; 11(12)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34947688

RESUMEN

Noniridescent and nonfading structural colors generated from metallic and dielectric nanoparticles with extraordinary optical properties hold great promise in applications such as image display, color printing, and information security. Yet, due to the strong wavelength dependence of optical constants and the radiation pattern, it is difficult and time-consuming to design nanoparticles with the desired hue, saturation, and brightness. Herein, we combined the Monte Carlo and Mie scattering simulations and a bidirectional neural network (BNN) to improve the design of gold nanoparticles' structural colors. The optical simulations provided a dataset including color properties and geometric parameters of gold nanoparticle systems, while the BNN was proposed to accurately predict the structural colors of gold nanoparticle systems and inversely design the geometric parameters for the desired colors. Taking the human chromatic discrimination ability as a criterion, our proposed approach achieved a high accuracy of 99.83% on the predicted colors and 98.5% on the designed geometric parameters. This work provides a general method to accurately and efficiently design the structural colors of nanoparticle systems, which can be exploited in a variety of applications and contribute to the development of advanced optical materials.

4.
Medicine (Baltimore) ; 97(13): e0161, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29595642

RESUMEN

BACKGROUND: To investigate the efficacy of febuxostat in hyperuricemic patients with chronic kidney disease (CKD), relevant randomized clinical trials (RCTs) were analyzed. METHODS: We used PubMed, Medline, ISI Web of Science, CBMdisc, and Cochrane Library databases to conduct a systematic literature research. A fixed-effects model was used to evaluate the standardized mean differences (SMDs) with 95% confidence intervals (CIs). We conducted subgroup analysis, sensitivity analysis, and analyzed publication bias, to comprehensively estimate the renoprotective effects of febuxostat in hyperuricemic patients with CKD. RESULTS: Among 296 retrieved studies, 5 relevant RCTs were included in the meta-analysis. The result showed that serum estimated glomerular filtration rate (eGFR) was improved after febuxostat treatment in hyperuricemic patients with CKD, with an SMD (95% CI) of 0.24 [-0.17 to 0.43] and P = .67 (fixed-effects model). No heterogeneity was observed across studies (I  = 0% and P = .67). Subgroup analysis suggested that treatment-related reductions in serum eGFR levels were not related to drug doses, intervention times, or region. CONCLUSIONS: The present meta-analysis suggests that febuxostat may slow the progression of mild-to-moderate CKD. Given the limited number of included studies, additional large sample-size RCTs are required to determine the long-term renoprotective effects of febuxostat in hyperuricemic patients with CKD.


Asunto(s)
Febuxostat/uso terapéutico , Supresores de la Gota/uso terapéutico , Hiperuricemia/complicaciones , Hiperuricemia/tratamiento farmacológico , Insuficiencia Renal Crónica/complicaciones , Humanos
5.
Medicine (Baltimore) ; 96(39): e8183, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28953677

RESUMEN

BACKGROUND: Metformin is effective for the treatment of polycystic ovary syndrome (PCOS), but conflicting results regarding its impact on serum levels of C-reactive protein (CRP) and interleukin-6 (IL-6) in women with PCOS have been reported. To provide high-quality evidence about the effect of treatment with metformin on CRP and IL-6 in PCOS, relevant studies that assessed the serum levels of CRP and IL-6 in women with PCOS receiving metformin treatment were reviewed and analyzed. METHODS: A literature search was conducted in the Science Citation Index, PubMed, Embase, and Cochrane Library databases, and personal contact was made with the authors. Random-effects model was used to estimate the standardized mean differences (SMDs) with 95% confidence intervals (95% CIs). To ensure synthesis of the best available evidence, subgroup analysis, sensitivity analysis, meta-regression analysis, and publication bias were performed. RESULTS: Of 216 studies identified, 20 were included in the meta-analysis (7 prospective, nonrandomized studies, and 13 randomized control trials). Data suggest that serum levels of CRP were decreased after metformin treatment in PCOS patients with an SMD (95% CI) of -0.86 [-1.24 to -0.48] and P = .000 (random-effects). However, significant heterogeneity was detected across studies (I = 84.6% and P = .000). Unfortunately, the sources of heterogeneity were not found by subgroup analysis and meta-regression analysis. Serum IL-6 concentrations were not significantly changed after metformin treatment in PCOS with an SMD (95% CI) of -0.48 [-1.26 to 0.31] and P > .05 (random-effects). Significant heterogeneity was also detected across studies (I = 90.9% and P = .000). The subgroup analysis suggested that treatment-related reductions in serum IL-6 levels were significantly correlated with BMI, whereas the sources of heterogeneity were not found. In addition, we noticed that metformin treatment could decrease BMI in the CRP and IL-6 related studies (SMD = -0.45, 95% CI: -0.68 to -0.23; SMD = -0.44, 95% CI: -0.73 to -0.16). CONCLUSION: This meta-analysis showed a significant decrease of serum CRP levels, especially in obese women, but no significant changes in IL-6 levels after metformin treatment in women with PCOS. In general, the data support that early metformin therapy may ameliorate the state of chronic inflammation in women with PCOS. Considering the obvious heterogeneity reported in the literature, further well-designed investigations with larger samples are needed to ascertain the long-term effects of metformin on chronic inflammation in PCOS.


Asunto(s)
Proteína C-Reactiva/análisis , Interleucina-6/sangre , Metformina/farmacología , Síndrome del Ovario Poliquístico , Femenino , Humanos , Hipoglucemiantes/farmacología , Evaluación del Resultado de la Atención al Paciente , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
Medicine (Baltimore) ; 96(51): e9212, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29390468

RESUMEN

RATIONALE: Diabetic foot ulcer (DFU) is a chronic complication of diabetes characterized by continuity, repeatability, and nonhealing. In recent years, mesenchymal stem cells hydrogel complex has been a new emerging technique in the treatment of DFU. The placenta-derived mesenchymal stem cells (PDMSCs) hydrogel is multipotent, and can secrete growth factors, cytokines, and immunomodulatory substances which could accelerate wound healing. PATIENT CONCERNS: In this case report, we present a 57-year-old female with type 2 diabetes mellitus and a 20-day DFU.A wound bed located at the dorsalis pedis of the right foot, and conventional therapies had no effect on the foot. DIAGNOSES: The patient was confirmed a diagnosis of type 2 DM with diabetic foot (Wagner classification III). INTERVENTIONS: To assess the efficacy and safety of PDMSCs hydrogel in wound repair and to improve the rate of wound healing, we administered PDMSCs hydrogel (cell number: 1 × 10/cells/cm) topically into the wound with the patient's permission. OUTCOMES: The patient's foot ulcer was almost healed, and foot function in walking was well preserved. No complications were observed. No recurrence occurred in the subsequent 6 months. LESSONS: To the best of our knowledge, this is the first patient globally to receive PDMSCs hydrogel to treat DFU. The present case study suggests that PDMSCs hydrogel may provide a new approach to DFU treatment. Clinical Trial Registration-URL: http://www.chictr.org.cn/searchproj.aspx:chiCRT-ONC-16008732.


Asunto(s)
Pie Diabético/diagnóstico , Pie Diabético/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Placenta/citología , Cicatrización de Heridas/fisiología , Administración Tópica , Femenino , Estudios de Seguimiento , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Persona de Mediana Edad , Embarazo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
7.
Biomed Res Int ; 2017: 5905384, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28409158

RESUMEN

Studies have suggested that metformin can potentially decrease the incidence of cancer and improve survival outcomes. However, the association between metformin use and the incidence and survival of endometrial cancer (EC) remains controversial. So, a meta-analysis was performed. An electronic search was conducted using PubMed, EMBASE, and Web of Science. The outcome measures were relative risks (RRs) or hazard ratios (HRs) with 95% confidence intervals (CIs) comparing the EC incidence and survival in patients treated with and without metformin. Eleven studies involving 766,926 participants were included in this study. In the pooled analysis of five studies which evaluated the association of metformin use with the incidence of EC, we found that metformin use was associated with a 13% reduction in EC risk among patients with diabetes (RR = 0.87, 95% CI: 0.80-0.95; p = 0.006). In the pooled analysis of six retrospective cohort studies evaluating the effect of metformin on the survival of EC patients, we found that, relative to nonuse, metformin use significantly improved the survival of EC patients (HR = 0.63, 95% CI: 0.45-0.87; p = 0.006). This study showed that metformin use was significantly associated with a decreased incidence of EC in diabetes and a favorable survival outcome of EC patients.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/epidemiología , Metformina/uso terapéutico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/patología , Neoplasias Endometriales/patología , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos
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