RESUMEN
OBJECTIVE: To compare corneal and anterior segment morphology among children and adolescents with and without diabetes. MATERIALS AND METHODS: PubMed, Embase and Scopus databases were systematically searched. Studies that were observational in design were considered. Included studies should have been done in young children and/or adolescents and compared relevant outcomes of interest based on the diabetic status. The outcomes of interest were related to corneal morphology, morphology of lens, as well as important characteristics of anterior segment such as depth, pupillary diameter, intra-ocular pressure and axial length. The pooled effect sizes were reported as weighted mean difference (WMD). STATA software was used for statistical analysis. RESULTS: The meta-analysis included 17 studies. Diabetic children had lower corneal endothelial cell density (cells/mm2) (WMD -215.7, 95% CI: -406.5, -24.9), higher central corneal thickness (µm) (WMD 12.66, 95% CI: 5.47, 19.84), higher lenticular thickness (mm) (WMD 0.25, 95% CI: 0.13, 0.36) and density (WMD 3.02, 95% CI: 2.23, 3.81) than non-diabetic children. The anterior chamber depth (mm) (WMD -0.17, 95% CI: -0.24, -0.09) and pupillary diameter (mm) (WMD -0.61, 95% CI: -1.12, -0.10) was significantly reduced in diabetic children, compared to non-diabetic children. No differences in the corneal curvature, corneal diameter, spherical equivalent, intra-ocular pressure, axial length, tear film breakup time and Schirmer test were noted among diabetic and non-diabetic children. CONCLUSIONS: Significant structural changes in cornea and lens along with reduction in anterior chamber depth and pupillary diameter were found. These morphological changes may be indication for early and prompt management and underscore the need for more advanced ophthalmological evaluation techniques, in addition to routine examination.
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Diabetes Mellitus , Cristalino , Adolescente , Niño , Preescolar , Córnea , Humanos , Presión Intraocular , Refracción OcularRESUMEN
OBJECTIVE: The aim of this work was to investigate the transplantation efficacy of microencapsulated young market pig islets in a diabetic rat model. METHODS: Islets were isolated and purified from young market pigs obtained from a local slaughterhouse. The islets were encapsulated in barium alginate and subjected to a glucose-induced insulin release functional assay in culture. Microencapsulated islets were transplanted into diabetic Sprague-Dawley rats and removed after 30 days for histologic examination. RESULTS: The mean islet equivalent (IEQ) yield per gram of digested tissue was 3,125 ± 617 IEQ/g after isolation and 2,618 ± 917 IEQ/g after purification, respectively. Host rats' blood glucose concentrations normalized (from 22.3 ± 2.7 mmol/L to 5.1 ± 0.67 mmol/L) following encapsulated islet transplantation. After graft removal, hyperglycemia recurred in the rats, indicating that the grafts were responsible for maintaining euglycemia. Histology revealed viable islets in the capsules 30 days after graft removal. Immunolabeling of insulin verified that ß-cells within the capsules remained well granulated. No fibrosis or immune cells were found in histopathology. CONCLUSIONS: Barium alginate encapsulation of young market pig islets can normalize glucose regulation in diabetic rats without fibrosis or an immunologic response.
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Diabetes Mellitus Experimental/cirugía , Composición de Medicamentos/métodos , Trasplante de Islotes Pancreáticos/métodos , Trasplante Heterólogo/métodos , Alginatos , Animales , Diabetes Mellitus Experimental/sangre , Hiperglucemia/etiología , Islotes Pancreáticos/fisiología , Trasplante de Islotes Pancreáticos/inmunología , Masculino , Ratas , Ratas Sprague-Dawley , Sus scrofaRESUMEN
OBJECTIVE: To explore whether lncRNA UCA1 (long non-coding RNA urothelial carcinoma associated 1) could promote the development of papillary thyroid carcinoma (PTC) via Wnt pathway and its underlying mechanism. PATIENTS AND METHODS: UCA1 expression in PTC tissues, paracancerous tissues, and thyroid cancer cells were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). UCA1 lentivirus was then constructed for the following in vitro experiments. Proliferative ability of MTC and SW579 cells was detected by cell counting kit-8 (CCK-8) and colony formation assay. Cell apoptosis after altering UCA1 expression in MTC and SW579 cells was detected by flow cytometry and Western blot. Invasive ability of MTC and SW579 cells was detected by transwell and wound healing assay. Finally, protein expressions of Wnt pathway-related genes were detected by Western blot. RESULTS: UCA1 was overexpressed in PTC tissues and thyroid cancer cells. UCA1 expression was positively correlated to tumor size, tumor stage, and metastasis of PTC. Overexpressed UCA1 promoted proliferation and invasion, whereas inhibited apoptosis of thyroid cancer cells via Wnt pathway. CONCLUSIONS: Overexpressed UCA1 promotes PTC development by stimulating proliferation, migration, and anti-apoptosis of thyroid cancer cells via activating Wnt pathway.
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ARN Largo no Codificante/fisiología , Cáncer Papilar Tiroideo/etiología , Neoplasias de la Tiroides/etiología , Vía de Señalización Wnt/fisiología , Adulto , Anciano , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Humanos , Persona de Mediana Edad , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patologíaRESUMEN
Powdery mildew (PM) of cucumber (Cucumis sativus), caused by Podosphaera xanthii, is a major foliar disease worldwide and resistance is one of the main objectives in cucumber breeding programs. The resistance to PM in cucumber stem is important to the resistance for the whole plant. In this study, genetic analysis and gene mapping were implemented with cucumber inbred lines NCG-122 (with resistance to PM in the stem) and NCG-121 (with susceptibility in the stem). Genetic analysis showed that resistance to PM in the stem of NCG-122 was qualitative and controlled by a single-recessive nuclear gene (pm-s). Susceptibility was dominant to resistance. In the initial genetic mapping of the pm-s gene, 10 SSR markers were discovered to be linked to pm-s, which was mapped to chromosome 5 (Chr.5) of cucumber. The pm-s gene's closest flanking markers were SSR20486 and SSR06184/SSR13237 with genetic distances of 0.9 and 1.8 cM, respectively. One hundred and fifty-seven pairs of new SSR primers were exploited by the sequence information in the initial mapping region of pm-s. The analysis on the F2 mapping population using the new molecular markers showed that 17 SSR markers were confirmed to be linked to the pm-s gene. The two closest flanking markers, pmSSR27and pmSSR17, were 0.1 and 0.7 cM from pm-s, respectively, confirming the location of this gene on Chr.5. The physical length of the genomic region containing pm-s was 135.7 kb harboring 21 predicted genes. Among these genes, the gene Csa5G623470 annotated as encoding Mlo-related protein was defined as the most probable candidate gene for the pm-s. The results of this study will provide a basis for marker-assisted selection, and make the benefit for the cloning of the resistance gene.
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Cucumis/genética , Genes de Plantas , Inmunidad de la Planta/genética , Ascomicetos/patogenicidad , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Cucumis/inmunología , Cucumis/microbiología , Sitios Genéticos , Repeticiones de Microsatélite , Tallos de la Planta/genética , Tallos de la Planta/microbiologíaRESUMEN
Objective: To explore the clinical characteristics of bronchiectasis(BR)coexisting in patients with rheumatoid arthritis (RA). Methods: One hundred and forty-eight bronchiectasis patients were retrospectively analyzed. These cases were all diagnosed in the Respiratory Department of Shanghai Pulmonary Hospital and Shanghai Gongli Hospital of Pudong New Area during Jan. 2012 to Dec.2015.The patients consisted of 74 males and 74 females, aging from 45 to 79 [mean(65±11)] years. In these patients, coexisting rheumatoid arthritis was found in 34 males and 36 females, aging from 45 to 79[mean(68±12)] years(RA-BR group). Patients with bronchiectasis alone consisted of 40 males and 38 females, aging from 49 to 76 [mean(63±10)] years (BR alone group). Data between the 2 groups of patients were compared, including general clinical features, serum anti-cyclic citrullinated peptide antibodies (anti-CCP), rheumatoid factor (RF), chest high-resolution CT (HRCT), and lung function . FACED scores were used to assess the severity of bronchiectasis. Meanwhile, we analyzed the correlation between anti-CCP and FACED scores in the 2 groups. Results: We observed an increase of serum anti-CCP in RA-BR patients compared with BR alone patients (196±68 versus 64±26, P<0.05). In addition, FACED scores in RA-BR patients were higher than those in BR patients (5.2±1.8 versus 3.1±1.4 , P< 0.05). Positive correlations between serum anti-CCP levels and FACED scores (r=0.678, r=0.461, P<0.05) in both RA-BR and BR alone groups were observed in this study. Conclusions: The disease severity scores of RA-BR patients were higher than those of patients with BR alone. Levels of serum anti-CCP may act as a predictor for the diagnosis and prognosis of bronchiectasis in patients with RA.
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Autoanticuerpos/sangre , Bronquiectasia/inmunología , Péptidos Cíclicos/sangre , Adulto , Anciano , Artritis Reumatoide/sangre , Artritis Reumatoide/epidemiología , Artritis Reumatoide/inmunología , Bronquiectasia/sangre , Bronquiectasia/epidemiología , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Factor Reumatoide/sangreRESUMEN
BACKGROUND: Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is a new determinate syndrome whose exact characteristics remain unclear. AIM: The objective of this study is to find more difference between ACOS and COPD. DESIGN: A retrospective study of ACOS and COPD in Chinese. METHODS: Data from 65 patients with ACOS and 65 patients with COPD were retrospectively collected and analyzed. The basis of this study was to compare the two groups while ruling out differences in age, sex and smoking history. RESULTS: Patients with ACOS tended to have earlier ages of onset, longer durations of symptoms, better nutritional status, higher single-breath diffusing capacity of carbon monoxide (DLCO) %predicted and airway resistance %predicted, more exacerbations in the preceding 12 months and shorter lengths of hospitalization. DLCO %predicted, airway resistance %predicted, and length of hospitalization were the variables most significantly associated with the presence of ACOS in patients with COPD. ROC correlating airway resistance %predicted value and current ACOS showed an optimal cutoff of airway resistance %predicted of over 296.6. During follow-up (median: 45 months; interquartile range: 6-82 months), 16 patient deaths were recorded (3 patients with ACOS). The risk remained significantly higher in patients with COPD alone than in patients with ACOS (HR 3.932; 95% CI 1.083-19.755; P = 0.046). CONCLUSION: Patients with ACOS were more likely to have better prognoses and lower mortality than those with COPD alone, though with greater exacerbation frequency.
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Asma/complicaciones , Asma/mortalidad , Hospitalización/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Anciano , China/epidemiología , Comorbilidad , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Humanos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Encuestas y Cuestionarios , Análisis de Supervivencia , Evaluación de Síntomas , SíndromeRESUMEN
OBJECTIVE: To analyze the characteristics of distribution and drug resistance of bacterial infection in several different parts of hematology department inpatients of Anhui Provincial Hospital from January 2010 to December 2014, including patients who had received hematopoietic stem cell transplantation (HSCT). METHODS: Anti-microbial susceptibility test was done by Kirby-Bauer method and automated systems and the data were analysed by WHONET 5.6 software. RESULTS: A total of 3 312 copies of inspection samples were analyzed, including 2 716 (82%) blood samples and other 596 specimens (18%). 634 bacterial strains were isolated from 3 312 samples (19.14%) including 488 samples (76.97%) from blood culture. 427 (67.35%) bacterial strains were gram-negative, and the other 207 (32.65%) were gram-positive. Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were most common gram-negative bacterial and the resistant rates to imipenem were 0.8%, 11.8% and 3.3%, respectively. Detection rates of Extended-spectrum beta-lactamases in Escherichia coli and Klebsiella pneumoniae were 83.9% and 75.0%, respectively. At the same time, Coagulase negative Staphylococcus, Streptococcus and Enterococcus were most common kinds of gram-positive bacteria. Methicillin-resistant coagulase negative staphylococcus accounted for 65.9% antibiotic resistance. No vancomycin and/or linezolid and/or tigecycline resistant strains of Staphylococcus spp. and Enterococcus spp. were found in those patients. CONCLUSION: Patients with hematology diseases had a higher risk of bacterial infections, mainly caused by Gram-negative bacteria. There are different distributions of bacterial in different wards.
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Infecciones Bacterianas/epidemiología , Farmacorresistencia Bacteriana , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/aislamiento & purificación , Enfermedades Hematológicas/epidemiología , Enfermedades Hematológicas/microbiología , Hematología , Trasplante de Células Madre Hematopoyéticas , Departamentos de Hospitales , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
The association between the CCDC26 rs4295627 single nucleotide polymorphism (SNP) and the glioma risk has been studied previously, but these studies have yielded conflicting results. The aim of the present study is to analyze this association more vigorously, by means of a meta-analysis. A comprehensive literature search was performed in databases PubMed and EMBASE. Six articles including 12 case-control studies in English with 11,368 controls and 5891 cases were eligible for the meta-analysis. We conducted subgroup analyses by the source of controls, ethnicity, and country. Our meta-analysis revealed that the rs4295627 SNP was associated with the glioma risk in a heterozygote model (TG versus TT: odds ratio = 1.35, 95% confidence interval = 1.26-1.45, P = 0.066). Moreover, our results suggested that the rs4295627 SNP was associated with a notably increased risk of glioma among Caucasians except for Swedes in 4 models (the homozygote model, recessive model, dominant model, and additive model). Nonetheless, in Sweden and China, the results showed no associations. No evidence of the publication bias was uncovered. Thus, our meta-analysis suggests that the rs4295627 SNP is associated with an increased risk of glioma. Additional studies are needed to derive more precise conclusion.
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Neoplasias Encefálicas/genética , Glioma/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Polimorfismo de Nucleótido Simple , Neoplasias Encefálicas/etnología , Estudios de Casos y Controles , China , Glioma/etnología , Humanos , ARN Largo no Codificante , SueciaRESUMEN
Administration of corticosteroids to patients affected by influenza virus, especially pandemic avian influenza virus, although relatively common, remains controversial. A systematic review and meta-analysis was performed to assess the impact of corticosteroid treatment on outcomes of patients with influenza virus infection. The PubMed, EMBASE, Web of Science and Cochrane Library databases were searched up to February, 2015. Studies comparing corticosteroid treatment with no corticosteroid treatment in patients with influenza virus infection were included. The primary outcomes assessed were the association of mortality and nosocomial infection with corticosteroid treatment. Two authors independently extracted the data. ORs and weighted mean differences (WMDs) were used to describe dichotomous data and continuous data, respectively. Nineteen studies with 4916 patients were included in this meta-analysis. The results showed that corticosteroid treatment was significantly associated with mortality (OR 1.98, 95% CI 1.62-2.43, p < 0.00001) and nosocomial infection (OR 3.16, 95% CI 2.09-4.78, p < 0.00001). The durations of mechanical ventilation (WMD 3.82, 95% CI 1.49-6.15, p 0.001) and intensive-care unit stay (WMD 4.78, 95% CI 2.27-7.29, p 0.0002) were both markedly longer in the corticosteroid treatment group than in the control group. These findings suggest that routine steroid use may not be ideal for influenza virus infection. However, these results are derived from observational studies, with some important biases. They should be examined in future sufficiently powered randomized trials.
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Corticoesteroides/uso terapéutico , Antiinflamatorios/uso terapéutico , Gripe Humana/tratamiento farmacológico , Corticoesteroides/efectos adversos , Antiinflamatorios/efectos adversos , Infección Hospitalaria/epidemiología , Humanos , Gripe Humana/complicaciones , Gripe Humana/mortalidad , Tiempo de Internación , Respiración Artificial , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
A key issue facing integrated water resources management and water pollution control is to address the vague parametric information. A full credibility-based chance-constrained programming (FCCP) method is thus developed by introducing the new concept of credibility into the modeling framework. FCCP can deal with fuzzy parameters appearing concurrently in the objective and both sides of the constraints of the model, but also provide a credibility level indicating how much confidence one can believe the optimal modeling solutions. The method is applied to Heshui River watershed in the south-central China for demonstration. Results from the case study showed that groundwater would make up for the water shortage in terms of the shrinking surface water and rising water demand, and the optimized total pumpage of groundwater from both alluvial and karst aquifers would exceed 90% of its maximum allowable levels when credibility level is higher than or equal to 0.9. It is also indicated that an increase in credibility level would induce a reduction in cost for surface water acquisition, a rise in cost from groundwater withdrawal, and negligible variation in cost for water pollution control.
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Conservación de los Recursos Naturales/métodos , Contaminación del Agua/prevención & control , Recursos Hídricos/provisión & distribución , Abastecimiento de Agua/estadística & datos numéricos , China , Monitoreo del Ambiente , Ríos/química , Contaminación del Agua/estadística & datos numéricosRESUMEN
This study proposes an environmental- and health-risk-induced remediation design approach for benzene-contaminated groundwater. It involves exposure frequency and intake rates that are important but difficult to be exactly quantified as breakthrough point. Flexible health-risk control is considered in the simulation and optimization work. The proposed approach is then applied to a petroleum-contaminated site in western Canada. Different situations about remediation durations, public concerns, and satisfactory degrees are addressed by the approach. The relationship between environmental standards and health-risk limits is analyzed, in association with their effect on remediation costs. Insights of three uncertain factors (i.e. exposure frequency, intake rate and health-risk threshold) for the remediation system are also explored, on a basis of understanding their impacts on health risk as well as their importance order. The case study results show that (1) nature attenuation plays a more important role in long-term remediation scheme than the pump-and-treat system; (2) carcinogenic risks have greater impact on total pumping rates than environmental standards for long-term remediation; (3) intake rates are the second important factor affecting the remediation system's performance, followed by exposure frequency; (4) the 10-year remediation scheme is the most robust choice when environmental and health-risk concerns are not well quantified.
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Benceno/análisis , Restauración y Remediación Ambiental , Agua Subterránea/análisis , Contaminantes Químicos del Agua/análisis , Canadá , Restauración y Remediación Ambiental/economía , Restauración y Remediación Ambiental/métodos , Petróleo/análisis , Medición de Riesgo , IncertidumbreRESUMEN
The methylation of tumor suppressor genes has been shown to be involved in many human cancers. 5-Aza-2'-deoxycytidine (5-Aza-CdR) can reactivate the expression of methylated tumor suppressor genes. In our study, 2 human cervical cancer cell lines, HeLa and SiHa, were treated with different concentrations (20, 10, 5, and 2.5 µM) of 5-Aza-CdR for 24, 48, and 72 h. After incubation, cells were analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and flow cytometry. The expression of RASSF1A and APAF-1 was detected by RT-PCR. 5-Aza-CdR inhibited the growth of HeLa and SiHa cells at different concentrations. The strongest inhibition and apoptosis rates were obtained after incubation for 72 h (5.63 ± 1.38 and 8.24 ± 2.40%, respectively). No significant difference in the expression of RASSF1A was found upon drug treatment, while APAF-1 expression increased in HeLa cells after treatment (0.790 ± 0.056%). Our results suggest that the tumor-suppressive effect of 5-Aza-CdR may result from the reactivation of silenced APAF-1 through demethylation.
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Apoptosis/efectos de los fármacos , Apoptosis/genética , Azacitidina/análogos & derivados , Metilación de ADN/efectos de los fármacos , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/genética , Factor Apoptótico 1 Activador de Proteasas/genética , Azacitidina/farmacología , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/genética , Línea Celular Tumoral , Decitabina , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Proteínas Supresoras de Tumor/genética , Neoplasias del Cuello Uterino/patologíaRESUMEN
We investigated voltage-dependent K(+) currents (I(K)) in noradrenergic (NAergic) A7 neurons. The I(K) evoked consisted of A-type I(K) (I(A)), which had the characteristics of a low threshold for activation (approximately -50 mV), fast activation/inactivation, and rapid recovery from inactivation. Since the I(A) were blocked by heteropodatoxin-2 (Hptx-2), a specific Kv4 channel blocker, and the NAergic A7 neurons were shown to be reactive with antibodies against Kv4.1/Kv4.3 channel proteins, we conclude that the I(A) evoked in NAergic neurons are mediated by Kv4.1/Kv4.3 channels. I(A) were also evoked using voltage commands of a single action potential (AP), a subthreshold voltage change between two consecutive APs, or excitatory postsynaptic potential (EPSP) activity recorded in current-clamp mode (CCM). Blockade of the I(A) by 4-AP, a broad spectrum I(A) blocker, or by Hptx-2 increased the half-width and spontaneous firing of APs and reduced the amount of synaptic drive needed to elicit APs in CCM, showing that the I(A) play important roles in regulating the shape and firing frequency of APs and in synaptic integration in NAergic A7 neurons. Since these neurons are the principal projection neurons to the dorsal horn of the spinal cord, these results also suggest roles for Kv4.1/4.3 channels in descending NAergic pain regulation.
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Potenciales de Acción , Tronco Encefálico/fisiología , Neuronas/fisiología , Norepinefrina/metabolismo , Canales de Potasio/fisiología , Transmisión Sináptica , Animales , Dopamina beta-Hidroxilasa/metabolismo , Femenino , Técnicas In Vitro , Masculino , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley , Canales de Potasio Shal/fisiologíaRESUMEN
Solving groundwater remediation optimization problems based on proxy simulators can usually yield optimal solutions differing from the "true" ones of the problem. This study presents a new stochastic optimization model under modeling uncertainty and parameter certainty (SOMUM) and the associated solution method for simultaneously addressing modeling uncertainty associated with simulator residuals and optimizing groundwater remediation processes. This is a new attempt different from the previous modeling efforts. The previous ones focused on addressing uncertainty in physical parameters (i.e. soil porosity) while this one aims to deal with uncertainty in mathematical simulator (arising from model residuals). Compared to the existing modeling approaches (i.e. only parameter uncertainty is considered), the model has the advantages of providing mean-variance analysis for contaminant concentrations, mitigating the effects of modeling uncertainties on optimal remediation strategies, offering confidence level of optimal remediation strategies to system designers, and reducing computational cost in optimization processes.
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Restauración y Remediación Ambiental/métodos , Modelos Estadísticos , Purificación del Agua/métodos , Procesos EstocásticosRESUMEN
A new stochastic optimization model under modeling uncertainty (SOMUM) and parameter certainty is applied to a practical site located in western Canada. Various groundwater remediation strategies under different significance levels are obtained from the SOMUM model. The impact of modeling uncertainty (proxy-simulator residuals) on optimal remediation strategies is compared to that of parameter uncertainty (arising from physical properties). The results show that the increased remediation cost for mitigating modeling-uncertainty impact would be higher than those from models where the coefficient of variance of input parameters approximates to 40%. This provides new evidence that the modeling uncertainty in proxy-simulator residuals can hardly be ignored; there is thus a need of investigating and mitigating the impact of such uncertainties on groundwater remediation design. This work would be helpful for lowering the risk of system failure due to potential environmental-standard violation when determining optimal groundwater remediation strategies.
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Restauración y Remediación Ambiental/métodos , Modelos Estadísticos , Purificación del Agua/métodos , Canadá , Procesos EstocásticosRESUMEN
This study provides a coupled simulation-optimization approach for optimal design of petroleum-contaminated groundwater remediation under uncertainty. Compared to the previous approaches, it has the advantages of: (1) addressing the stochasticity of the modeling parameters in simulating the flow and transport of NAPLs in groundwater, (2) providing a direct and response-rapid bridge between remediation strategies (pumping rates) and remediation performance (contaminant concentrations) through the created proxy models, (3) alleviating the computational cost in searching for optimal solutions, and (4) giving confidence levels for the obtained optimal remediation strategies. The approach is applied to a practical site in Canada for demonstrating its performance. The results show that mitigating the effects of uncertainty on optimal remediation strategies (through enhancing the confidence level) would lead to the rise of remediation cost due to the increase in the total pumping rate.
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Restauración y Remediación Ambiental/métodos , Agua Subterránea/química , Modelos Químicos , Petróleo/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Canadá , Suelo/química , Incertidumbre , Movimientos del AguaRESUMEN
Municipal solid waste (MSW) should be properly disposed in order to help protect environmental quality and human health, as well as to preserve natural resources. During MSW disposal processes, a large amount of greenhouse gas (GHG) is emitted, leading to a significant impact on climate change. In this study, an inexact dynamic optimization model (IDOM) is developed for MSW-management systems under uncertainty. It grounds upon conventional mixed-integer linear programming (MILP) approaches, and integrates GHG components into the modeling framework. Compared with the existing models, IDOM can not only deal with the complex tradeoff between system cost minimization and GHG-emission mitigation, but also provide optimal allocation strategies under various emission-control standards. A case study is then provided for demonstrating applicability of the developed model. The results indicate that desired waste-flow patterns with a minimized system cost and GHG-emission amount can be obtained. Of more importance, the IDOM solution is associated with over 5.5 million tonnes of TEC reduction, which is of significant economic implication for real implementations. Therefore, the proposed model could be regarded as a useful tool for realizing comprehensive MSW management with regard to mitigating climate-change impacts.
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Gases/análisis , Efecto Invernadero , Eliminación de Residuos/métodos , Administración de Residuos/métodos , China , Planificación de Ciudades , Clima , Humanos , Modelos Teóricos , Eliminación de Residuos/economía , Eliminación de Residuos/normas , Transportes , Administración de Residuos/economía , Administración de Residuos/normasRESUMEN
A number of inexact programming methods have been developed for municipal solid waste management under uncertainty. However, most of them do not allow the parameters in the objective and constraints of a programming problem to be functional intervals (i.e., the lower and upper bounds of the intervals are functions of impact factors). In this study, a flexible interval mixed-integer bi-infinite programming (FIMIBIP) method is developed in response to the above concern. A case study is also conducted; the solutions are then compared with those obtained from interval mixed-integer bi-infinite programming (IMIBIP) and fuzzy interval mixed-integer programming (FIMIP) methods. It is indicated that the solutions through FIMIBIP can provide decision support for cost-effectively diverting municipal solid waste, and for sizing, timing and siting the facilities' expansion during the entire planning horizon. These schemes are more flexible than those identified through IMIBIP since the tolerance intervals are introduced to measure the level of constraints satisfaction. The FIMIBIP schemes may also be robust since the solutions are "globally-optimal" under all scenarios caused by the fluctuation of gas/energy prices, while the conventional ones are merely "locally-optimal" under a certain scenario.
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Modelos Teóricos , Eliminación de Residuos/métodos , Administración de Residuos/métodos , Técnicas de Apoyo para la Decisión , Matemática , Eliminación de Residuos/economía , Análisis de Sistemas , Administración de Residuos/economíaRESUMEN
A simulation-aided 2-level factorial analysis approach is proposed to characterize the interactive effects of composting factors (i.e. temperature, moisture, oxygen content and initial biomass concentration) on composting processes. To screen the important effect factors when high-order interactions occur, normal probability plot is applied to the result analysis. The results show that the factors have various effects on the composting process in different stages. At the 24th hour, the factors do not show significant effects on the composting process. At the 72nd hour when the composting process reaches active stage, the factors have important effects on the composting process, and their interactive effects are also significant. At the 144th hour, temperature and oxygen content still have effects on the composting process, but not as significant as those at the active stage. These findings could be useful for guiding composting-process operation and management and developing associated control strategies in different composting stages.
Asunto(s)
Suelo , Análisis Factorial , Modelos TeóricosRESUMEN
The A7 catecholamine cell group consists of noradrenergic (NAergic) neurons that project to the dorsal horn of the spinal cord. Here, we characterized their morphology and physiology properties and tested the effect of substance P (Sub-P) on them, since the results of many morphological studies suggest that A7 neurons are densely innervated by Sub-P-releasing terminals from nuclei involved in the descending inhibitory system, such as the lateral hypothalamus and periaqueductal gray area. Whole cell recordings were made from neurons located approximately 200 microm rostral to the trigeminal motor nucleus (the presumed A7 area) in sagittal brainstem slices from rats aged 7-10 days. After recording, the neurons were injected with biocytin and immunostained with antibody against dopamine-beta-hydroxylase (DBH). DBH-immunoreactive (ir) cells were presumed to be NAergic neurons. They had a large somata diameter ( approximately 20 microm) and relatively simple dendritic branching patterns. They fired action potentials (AP) spontaneously with or without blockade of synaptic inputs, and had similar properties to those of NAergic neurons in other areas, including the existence of calcium channel-mediated APs and a voltage-dependent delay in initiation of the AP (an indicator of the existence of A-type potassium currents) and an ability to be hyperpolarized by norepinephrine. Furthermore, in all DBH-ir neurons tested, Sub-P caused depolarization of the membrane potential and an increase in neuronal firing rate by acting on neurokinin-1 receptors. Non-DBH-ir neurons with a smaller somata size were also found in the A7 area. These showed great diversity in firing patterns and about half were depolarized by Sub-P. Morphological examination suggested that the non-DBH-ir neurons form contacts with DBH-ir neurons. These results provide the first description of the intrinsic regulation of membrane properties of, and the excitatory effect of Sub-P on, A7 area neurons, which play an important role in pain regulation.