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1.
J Environ Manage ; 365: 121620, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38941848

RESUMEN

Accurate quantification of flow dynamics during reservoir ecological scheduling hinders the maintenance of normal reproductive activities in downstream riverine fish. This study proposed a quantitative method for determining the flow rate changes in reservoir ecological scheduling. The approach utilized the daily flow rate and daily flow-rate increment to characterize the flow process. Adopting the perspective of shifting spawning grounds of adhesive egg-laying fish species in response to flow rate variations, we introduced the Spawning Ground Overlap Rate as an indicator and utilized it to determine flow rate changes. Focusing on the downstream area of the Yangqu Hydropower Station in the upper reaches of the Yellow River, we calculated the distribution of spawning grounds and the Spawning Ground Overlap Rate in the region. We set a threshold for the Spawning Ground Overlap Rate to restrict the flow rate changes. The results indicated that during the fish spawning period, the ecological flow range in the downstream area of the Yangqu Dam was 480-1200 m3/s. It was required to maintain a daily flow rate change of less than 49.45 m3/(s·d) and a maximum seven-day flow difference of less than 227.76 m3/s to maintain the optimal level of spawning ground overlap rate. Additionally, it was necessary to keep the daily flow rate change below 123.83 m3/(s·d) and the maximum seven-day flow difference below 368.84 m3/s to maintain the minimum spawning ground overlap rate. The findings provide foundational data for determining flow dynamics during the ecological scheduling of the spawning period for viscous-spawning fish.


Asunto(s)
Ríos , Animales , Peces/fisiología , Reproducción , Ecosistema , Ecología , China , Movimientos del Agua
2.
Transpl Int ; 35: 10422, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35692736

RESUMEN

Relationships between renal function and medical costs for deceased donor kidney transplant recipients are not fully quantified post-transplant. We describe these relationships with renal function measured by estimated glomerular filtration rate (eGFR) and graft failure. The United States Renal Data System identified adults receiving single-organ deceased donor kidneys 2012-2015. Inpatient, outpatient, other facility costs and eGFRs at discharge, 6 and 12 months were included. A time-history of costs was constructed for graft failures and monthly costs in the first year post-transplant were compared to those without failure. The cohort of 24,021 deceased donor recipients had a 2.4% graft failure rate in the first year. Total medical costs exhibit strong trends with eGFR. Recipients with 6-month eGFRs of 30-59 ml/min/1.73m2 have total costs 48% lower than those <30 ml/min/1.73m2. For recipients with graft failure monthly costs begin to rise 3-4 months prior to failure, with incremental costs of over $38,000 during the month of failure. Mean annual total incremental costs of graft failure are over $150,000. Total costs post-transplant are strongly correlated with eGFR. Graft failure in the first year is an expensive, months-long process. Further reductions in early graft failures could yield significant human and economic benefits.


Asunto(s)
Trasplante de Riñón , Adulto , Tasa de Filtración Glomerular , Supervivencia de Injerto , Humanos , Riñón/fisiología , Riñón/cirugía , Donantes de Tejidos , Estados Unidos
3.
BMC Geriatr ; 22(1): 484, 2022 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-35658904

RESUMEN

BACKGROUND: Falls are the leading cause of injury-related death among older Americans. While some research has found that insomnia heightens falls, health care resource utilization (HCRU) and costs, the impact of insomnia treatments on fall risk, mortality, HCRU and costs in the elderly population, which could be of substantial interest to payers, has not been fully elucidated. This study evaluated the risk of falls and related consequences among adults ≥ 65 years of age treated with common prescription medications for insomnia compared with non-sleep disordered controls. METHODS: This was a retrospective cohort analysis of deidentified Medicare claims from January 2011 through December 2017. Medicare beneficiaries treated for insomnia receiving zolpidem extended-release, zolpidem immediate-release, trazodone, or benzodiazepines were matched with non-sleep disordered controls. The main outcomes were falls, mortality, healthcare resource utilization (HCRU), and medical costs during the 12 months following the earliest fill date for the insomnia medication of interest. Generalized linear models controlled for several key covariates, including age, race, sex, geographic region and Charlson Comorbidity Index score. RESULTS: The study included 1,699,913 Medicare beneficiaries (59.9% female, mean age 75 years). Relative to controls, adjusted analyses showed that beneficiaries receiving insomnia medication experienced over twice as many falls (odds ratio [OR] = 2.34, 95% CI: 2.31-2.36). In adjusted analyses, patients receiving benzodiazepines or trazodone had the greatest risk. Crude all-cause mortality rates were 15-times as high for the insomnia-treated as controls. Compared with controls, beneficiaries receiving insomnia treatment demonstrated higher estimated adjusted mean number of inpatient, outpatient, and emergency department visits and longer length of inpatient stay. All-cause total adjusted mean costs were higher among insomnia treated patients ($967 vs $454). CONCLUSIONS: Individuals receiving insomnia treatment had an increased risk of falls and mortality and higher HCRU and costs compared with matched beneficiaries without sleep disorders. Trazodone and benzodiazepines were associated with the greatest risk of falls. This analysis suggests that significant risks are associated with common, older generation insomnia medication treatments in the elderly. Nonetheless, these results should be interpreted with caution as the use of these medications may be indicative of underlying morbidity with potential for residual confounding.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Trazodona , Accidentes por Caídas , Anciano , Benzodiazepinas/uso terapéutico , Atención a la Salud , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Medicare , Estudios Retrospectivos , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Trazodona/efectos adversos , Estados Unidos/epidemiología , Zolpidem/efectos adversos
4.
J Obstet Gynaecol ; 42(8): 3712-3719, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36562187

RESUMEN

This study aimed to explore the parameters of the independent predictive characteristic pulse diagram of polycystic ovary syndrome (PCOS) by analysing the pulse characteristics between healthy women and the PCOS group. A total of 278 women were recruited for this study. Pulse wave parameters were collected by the pulse spectrum analyser. The single-factor analysis of the pulse diagram parameters was used to identify significant indicators, and the logistic regression analysis was carried out on the above indicators with statistical differences to obtain independent predictors. According to the single-factor and multi-factor analyses, h1, h5, h3/h1, t, t1 and t5 were independent predictors of PCOS diagnosis. The results showed that PCOS patients had a faster heart rate, decreased left ventricular systolic function and decreased aortic compliance compared to healthy individuals. These findings suggested that the characteristic pulse parameters screened out are valuable for the diagnosis of PCOS.IMPACT STATEMENTWhat is already known on this subject? Polycystic ovary syndrome (PCOS) is a common gynecological reproductive endocrine and metabolic disease, which is significant for screening and early intervention in the disease. However, due to the lack of pulse's diagnostic evidence of PCOS, there is still an unknown area in the research on the correlation between PCOS and pulse diagram parameters.What do the results of this study add? This study fills the gap between the research on PCOS and pulse wave. The study also shows that the pulse characteristic parameters h1, h5, h3/h1, t, t1, and t5 are independent predictors of PCOS, suggesting that the patients have a higher heart rate, lower ventricular systolic function, and aortic compliance than healthy individuals.What are the implications of these findings for clinical practice and/or further research? Prominent risk factors for pulse parameters associated with the occurrence of PCOS facilitate early screening and diagnosis of the disease. The objectification of pulse diagnosis helps to establish a health management model, which can be used for the accurate assessment and treatment of PCOS by traditional Chinese medicine (TCM). It provides a clinical reference for the study of pulse diagnosis objectification.


Asunto(s)
Ginecología , Síndrome del Ovario Poliquístico , Femenino , Humanos , Síndrome del Ovario Poliquístico/complicaciones , Frecuencia Cardíaca , Modelos Logísticos , Factores de Riesgo
5.
Protein Expr Purif ; 178: 105747, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32898688

RESUMEN

Structure heterogeneity and host nucleic acids contamination are two major problems for virus-like particles (VLPs) produced by various host cells. In this study, an in vitro optimized disassembly-purification-reassembly process was developed to obtain uniform and nucleic acid free hepatitis B core (HBc) based VLPs from E. coli fermentation. The process started with ammonium sulfate precipitation of all heterogeneous HBc structures after cell disintegration. Then, dissolution and disassembly of pellets into basic subunits were carried out under the optimized disassembly condition. All contaminants, including host nucleic acids and proteins, were efficiently removed with affinity chromatography. The purified subunits reassembled into VLPs by final removal of the chaotropic agent. Two uniform and nucleic acid free HBc-based VLPs, truncated HBc149 and chimeric HBc183-MAGE3 I, were successfully prepared. It was found that disassembly degree of HBc-based VLPs had a great influence on the protein yield, nucleic acid removal and reassembly efficiency. 4 M urea was optimal because lower concentration would not disassemble the particles completely while higher concentration would further denature the subunits into disordered aggregate and could not be purified and reassembled efficiently. For removal of strong binding nucleic acids such as in the case of HBc183-MAGE3 I, benzonase nuclease was added to the disassembly buffer before affinity purification. Through the optimized downstream process, uniform and nucleic acid free HBc149 VLPs and HBc183-MAGE3 I VLPs were obtained with purities above 90% and yields of 55.2 and 43.0 mg/L, respectively. This study would be a reference for efficient preparation of other VLPs.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B , Virus de la Hepatitis B , Virión , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Antígenos del Núcleo de la Hepatitis B/biosíntesis , Antígenos del Núcleo de la Hepatitis B/química , Antígenos del Núcleo de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/química , Virus de la Hepatitis B/genética , Ácidos Nucleicos/química , Virión/química , Virión/aislamiento & purificación , Virión/metabolismo
6.
Clin Transplant ; 34(10): e14022, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32573812

RESUMEN

Increased utilization of suboptimal organs in response to organ shortage has resulted in increased incidence of delayed graft function (DGF) after transplantation. Although presumed increased costs associated with DGF are a deterrent to the utilization of these organs, the financial burden of DGF has not been established. We used the Premier Healthcare Database to conduct a retrospective analysis of healthcare resource utilization and costs in kidney transplant patients (n = 12 097) between 1/1/2014 and 12/31/2018. We compared cost and hospital resource utilization for transplants in high-volume (n = 8715) vs low-volume hospitals (n = 3382), DGF (n = 3087) vs non-DGF (n = 9010), and recipients receiving 1 dialysis (n = 1485) vs multiple dialysis (n = 1602). High-volume hospitals costs were lower than low-volume hospitals ($103 946 vs $123 571, P < .0001). DGF was associated with approximately $18 000 (10%) increase in mean costs ($130 492 vs $112 598, P < .0001), 6 additional days of hospitalization (14.7 vs 8.7, P < .0001), and 2 additional ICU days (4.3 vs 2.1, P < .0001). Multiple dialysis sessions were associated with an additional $10 000 compared to those with only 1. In conclusion, DGF is associated with increased costs and length of stay for index kidney transplant hospitalizations and payment schemes taking this into account may reduce clinicians' reluctance to utilize less-than-ideal kidneys.


Asunto(s)
Trasplante de Riñón , Funcionamiento Retardado del Injerto/epidemiología , Rechazo de Injerto/epidemiología , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Riñón , Estudios Retrospectivos , Factores de Riesgo
7.
Biochem Biophys Res Commun ; 508(3): 667-674, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30527812

RESUMEN

Virus-induced signaling adaptor (VISA), which mediates the production of type I interferon, is crucial for the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) signaling pathway. Upon viral infection, RIG-I recognizes double-stranded viral RNA and interacts with VISA to mediate antiviral innate immunity. However, the mechanisms underlying RIG/VISA-mediated antiviral regulation remain unclear. In this study, we confirmed that receptor for activated C kinase 1 (RACK1) interacts with VISA and attenuates the RIG/VISA-mediated antiviral innate immune signaling pathway. Overexpression of RACK1 inhibited the interferon-ß (IFN-ß) promoter; interferon-stimulated response element (ISRE); nuclear factor kappa B (NF-κB) activation; and dimerization of interferon regulatory factor 3 (IRF3) mediated by RIG-I, VISA, and TANK-binding kinase 1 (TBK1). A reduction in RACK1 expression level upon small interfering RNA knockdown increased RIG/VISA-mediated antiviral transduction. Additionally, RACK1 disrupted formation of the VISA-tumor necrosis factor receptor-associated factor 2 (TRAF2), VISA-TRAF3, and VISA-TRAF6 complexes during RIG-I/VISA-mediated signal transduction. Additionally, RACK1 enhanced K48-linked ubiquitination of VISA, attenuated its K63-linked ubiquitination, and decreased VISA-mediated antiviral signal transduction. Together, these results indicate that RACK1 interacts with VISA to repress downstream signaling and downregulates virus-induced IFN-ß production in the RIG-I/VISA signaling pathway.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antivirales/metabolismo , Proteína 58 DEAD Box/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Cinasa C Activada/metabolismo , Transducción de Señal , Técnicas de Silenciamiento del Gen , Humanos , Interferón beta/biosíntesis , Interferón beta/metabolismo , Lisina/metabolismo , Complejos Multiproteicos/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Interferente Pequeño/metabolismo , Virus Sendai/fisiología , Péptidos y Proteínas Asociados a Receptores de Factores de Necrosis Tumoral/metabolismo , Ubiquitinación
8.
J Med Virol ; 91(3): 482-492, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30267576

RESUMEN

The mitochondrial antiviral signal protein mitochondrial antiviral signaling protein, also known as virus-induced signaling adaptor (VISA), plays a key role in regulating host innate immune signaling pathways. This study identifies FK506 binding protein 8 (FKBP8) as a candidate interacting protein of VISA through the yeast two-hybrid technique. The interaction of FKBP8 with VISA, retinoic acid inducible protein 1 (RIG-I), and IFN regulatory factor 3 (IRF3) was confirmed during viral infection in mammalian cells by coimmunoprecipitation. Overexpression of FKBP8 using a eukaryotic expression plasmid significantly attenuated Sendai virus-induced activation of the promoter interferons ß (IFN-ß), and transcription factors nuclear factor κ-light chain enhancer of activated B cells (NF-κB) and IFN-stimulated response element (ISRE). Overexpression of FKBP8 also decreased dimer-IRF3 activity, but enhanced virus replication. Conversely, knockdown of FKBP8 expression by RNA interference showed opposite effects. Further studies indicated that FKBP8 acts as a negative interacting partner to regulate RLR-VISA signaling by acting on VISA and TANK binding kinase 1 (TBK1). Additionally, FKBP8 played a negative role on virus-induced signaling by inhibiting the formation of TBK1-IRF3 and VISA-TRAF3 complexes. Notably, FKBP8 also promoted the degradation of TBK1, RIG-I, and TRAF3 resulting from FKBP8 reinforced Sendai virus-induced endogenous polyubiquitination of RIG-I, TBK1, and TNF receptor-associated factor 3 (TRAF3). Therefore, a novel function of FKBP8 in innate immunity antiviral signaling regulation was revealed in this study.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/inmunología , Inmunidad Innata , Virus Sendai , Transducción de Señal , Proteínas de Unión a Tacrolimus/genética , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Proteína 58 DEAD Box/genética , Proteína 58 DEAD Box/inmunología , Células HEK293 , Humanos , Factor 3 Regulador del Interferón/genética , Factor 3 Regulador del Interferón/inmunología , FN-kappa B/genética , FN-kappa B/inmunología , Unión Proteica , Proteínas Serina-Treonina Quinasas/inmunología , Receptores Inmunológicos , Factor 3 Asociado a Receptor de TNF/genética , Factor 3 Asociado a Receptor de TNF/inmunología , Técnicas del Sistema de Dos Híbridos , Ubiquitinación
9.
Biochem Biophys Res Commun ; 496(2): 422-428, 2018 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-29305862

RESUMEN

Hepatic ischemia reperfusion (I/R) injury is unavoidable in various clinical conditions. Despite considerable investigation, the underlying molecular mechanism revealing liver I/R injury remains elusive. Stromal interaction molecule 1 (STIM1) plays essential role in regulating the induction of cellular responses to a number of stress conditions, including temperature changes, elevated ROS, and hypoxia. Here, to explore if STIM1 is involved in hepatic injury, wild type (WT) and STIM1-knockout (STIM1-/-) mice were subjected to I/R. Our results indicated that the WT mice with hepatic I/R injury showed higher STIM1 expressions from gene and protein levels in liver tissue samples. Similar results were observed in hypoxia-exposed cells in vitro. Significantly, STIM1-/- attenuated hepatic injury compared to the WT mice after I/R, as evidenced by the improved pathological alterations in liver sections. WT mice subjected to liver I/R showed higher serum alanine aminotransferase (ALT) and aminotransferase (AST) levels, as well as pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß, which were significantly reduced by STIM1-/-. In addition, STIM1-/- also decreased the liver mRNA levels of pro-inflammatory cytokines in mice after I/R injury. Furthermore, significantly decreased oxidative stress was found in STIM1-/- mice after I/R injury compared to the WT group of mice, evidenced by the enhanced superoxide dismutase (SOD) activity and the reduced malondialdehyde (MDA) and reactive oxygen species (ROS) levels in liver tissue samples. Moreover, STIM1-/- mice with hepatic I/R injury displayed the down-regulated nuclear factor of activated T cell (NFAT1), Orai1 and cleaved Caspase-3 levels in liver, contributing to apoptosis suppression. The results above were confirmed in hypoxia-treated cells lacking of STIM1 expression. Together, the findings suggested that STIM1-deletion protects the liver from I/R injury in mice through inhibiting inflammation, oxidative stress and apoptosis. STIM1 could be considered as a potential therapeutic target to ameliorate I/R injury.


Asunto(s)
Macrófagos del Hígado/metabolismo , Hígado/metabolismo , Daño por Reperfusión/genética , Molécula de Interacción Estromal 1/genética , Alanina Transaminasa/sangre , Animales , Apoptosis/genética , Aspartato Aminotransferasas/sangre , Caspasa 3/genética , Caspasa 3/metabolismo , Regulación de la Expresión Génica , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos del Hígado/patología , Hígado/patología , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Estrés Oxidativo , Cultivo Primario de Células , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Daño por Reperfusión/prevención & control , Molécula de Interacción Estromal 1/deficiencia , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
10.
Eur J Mass Spectrom (Chichester) ; 23(3): 122-126, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28657436

RESUMEN

A series of coumarins were analyzed using electrospray ionization quadrupole time-of-flight tandem mass spectrometry in the positive-ion mode. Unexpected hydrated ions ([M + H2O + Na]+) was observed upon collision-induced dissociation of the sodiated ions ([M + Na]+) of eight coumarins. Several factors which affected relative abundance of [M + H2O + Na]+ ions such as collision energy, concentration and solvent were investigated. None of them have effect on the relative abundance of [M + H2O + Na]+. However, the peak of hydrated ions was not detected in the further collision-induced dissociation of protonated ions of coumarins. Apigenin and Quercetin sharing similar benzopyrone structural unit with coumarins are selected for tandem mass spectrometry analysis. There were no hydrated ions in their tandem mass spectrometry spectra of the precursor [M + Na]+ ions. Thus, both coumarins and sodium were necessary for the formation of [M + H2O + Na]+. Together with the result that hydrated ions are not formed by hydrolysis reactions, a six-membered ring structure which involves with the formation of [M + H2O + Na]+ was presented. And D-labeling experiment indicates that the H2O molecule did not come from solvent.


Asunto(s)
Cumarinas/análisis , Cumarinas/química , Iones/química , Sodio/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Agua/química , Hidrólisis , Sodio/análisis
11.
J Stroke Cerebrovasc Dis ; 26(6): 1233-1238, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28236594

RESUMEN

BACKGROUND: Disability and mortality represent the most relevant clinical outcomes after acute ischemic stroke. Recently, a number of prognostic models of acute ischemic stroke have been developed, but they have not been extensively validated. In this study, we evaluated the ability of 3 prognostic models including the iScore, the PLAN score, and the ASTRAL score in predicting clinical poor outcomes or mortality at 6 months in patients with acute ischemic stroke. METHODS: A total of 323 patients were divided into a good-prognosis group and a poor-prognosis group based on the modified Rankin Scale. Model discrimination was quantified by calculating the area under the receiver operating characteristic (ROC) curve, and calibration was assessed by Hosmer-Lemeshow goodness of fit test and Pearson correlation coefficient. RESULTS: We identified 96 (29.7%) patients with poor prognosis, including 21 who were dead. All 3 models showed good ability in predicting poor prognosis and mortality in patients with acute ischemic stroke (all ROC > .70). There was no difference between these 3 models in terms of sensitivity and accuracy (all P > .05). CONCLUSIONS: The results of this study suggest that the iScore, the PLAN score, and the ASTRAL score were equal in predicting 6-month poor prognosis and mortality in patients with acute ischemic stroke. Overall, there was a very high correlation between observed and expected outcomes at the risk score level.


Asunto(s)
Isquemia Encefálica/diagnóstico , Técnicas de Apoyo para la Decisión , Accidente Cerebrovascular/diagnóstico , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Isquemia Encefálica/mortalidad , Isquemia Encefálica/fisiopatología , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
12.
Opt Express ; 24(16): 18176-83, 2016 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-27505782

RESUMEN

Staggered AlGaN quantum wells (QWs) are designed to enhance the transverse-electric (TE) polarized optical emission in deep ultraviolet (DUV) light- emitting diodes (LED). The optical polarization properties of the conventional and staggered AlGaN QWs are investigated by a theoretical model based on the k·p method as well as polarized photoluminescence (PL) measurements. Based on an analysis of the valence subbands and momentum matrix elements, it is found that AlGaN QWs with step-function-like Al content in QWs offers much stronger TE polarized emission in comparison to that from conventional AlGaN QWs. Experimental results show that the degree of the PL polarization at room temperature can be enhanced from 20.8% of conventional AlGaN QWs to 40.2% of staggered AlGaN QWs grown by MOCVD, which is in good agreement with the theoretical simulation. It suggests that polarization band engineering via staggered AlGaN QWs can be well applied in high efficiency AlGaN-based DUV LEDs.

13.
Environ Sci Technol ; 50(10): 5007-16, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-27104794

RESUMEN

Geochemical fractionation is used to assess the significance of environmental factors on organic phosphorus (OP) pools in sediments. Labile, moderately labile, and nonlabile OP pools in the sediments from Lake Hulun, Inner Mongolia, were fractionated, and their responses to environmental conditions and lake evolution were investigated based on the spatial and vertical distribution of OP fractionations. In light of the recalcitrant characteristics of organic matter (OM) in different environmental conditions, the pH presents significant negative effects on the amount of labile OP, while water depth shows an important role in regulating the distribution between the moderately labile and nonlabile OP pools. A latitudinal zonation in the distribution of OP pools in surface sediments from different lakes was apparent with this zonation likely linked to the gradient effects of climate and anthropogenic activities on OM decomposition and thereby on the sediments capacity to hold phosphorus. These results show that OM plays a role in governing the impacts of weather and environmental factors on OP fractionation in aquatic environments. This work suggests that OP pools in the sediment core could be used as an archive for environmental conditions and lake evolution.


Asunto(s)
Lagos/química , Fósforo/química , Fraccionamiento Químico , Sedimentos Geológicos/química , Contaminantes Químicos del Agua
15.
ScientificWorldJournal ; 2014: 617162, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25258726

RESUMEN

Gas turbines are considered as one kind of the most important devices in power engineering and have been widely used in power generation, airplanes, and naval ships and also in oil drilling platforms. However, they are monitored without man on duty in the most cases. It is highly desirable to develop techniques and systems to remotely monitor their conditions and analyze their faults. In this work, we introduce a remote system for online condition monitoring and fault diagnosis of gas turbine on offshore oil well drilling platforms based on a kernelized information entropy model. Shannon information entropy is generalized for measuring the uniformity of exhaust temperatures, which reflect the overall states of the gas paths of gas turbine. In addition, we also extend the entropy to compute the information quantity of features in kernel spaces, which help to select the informative features for a certain recognition task. Finally, we introduce the information entropy based decision tree algorithm to extract rules from fault samples. The experiments on some real-world data show the effectiveness of the proposed algorithms.


Asunto(s)
Algoritmos , Entropía , Gases , Sistemas Microelectromecánicos/métodos , Modelos Teóricos , Simulación por Computador , Diseño de Equipo , Lógica Difusa , Humanos , Sistemas Microelectromecánicos/instrumentación , Tecnología de Sensores Remotos/métodos , Reproducibilidad de los Resultados
16.
Front Digit Health ; 6: 1463419, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39347446

RESUMEN

Introduction: Endometriosis (EMs) and adenomyosis (AD) are common gynecological diseases that impact women's health, and they share symptoms such as dysmenorrhea, chronic pain, and infertility, which adversely affect women's quality of life. Current diagnostic approaches for EMs and AD involve invasive surgical procedures, and thus, methods of noninvasive differentiation between EMs and AD are needed. This retrospective cohort study introduces a novel, noninvasive classification methodology employing a stacked ensemble machine learning (ML) model that utilizes peripheral blood and coagulation markers to distinguish between EMs and AD. Methods: The study included a total of 558 patients (329 with EMs and 229 with AD), in whom key hematological and coagulation markers were analyzed to identify distinctive profiles. Feature selection was conducted through ML (logistic regression, support vector machine, and K-nearest neighbors) to determine significant hematological markers. Results: Red cell distribution width, mean corpuscular hemoglobin concentration, activated partial thromboplastin time, international normalized ratio, and antithrombin III were proved to be the key distinguishing indexes for disease differentiation. Among all the ML classification models developed, the stacked ensemble model demonstrated superior performance (area under the curve = 0.803, 95% credibility interval = 0.701-0.904). Our findings demonstrate the effectiveness of the stacked ensemble ML model for classifying EMs and AD. Discussion: Integrating biomarkers into this multi-algorithm framework offers a novel approach to noninvasive diagnosis. These results advocate for the application of stacked ensemble ML utilizing cost-effective and readily available peripheral blood and coagulation indicators for the early, rapid, and noninvasive differential diagnosis of EMs and AD, offering a potentially transformative approach for clinical decision-making and personalized treatment strategies.

17.
Materials (Basel) ; 17(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611973

RESUMEN

Porous asphalt pavements are widely used in rainy and wet areas for their skid resistance, noise reduction, runoff minimization and environmental sustainability. Long-term moisture vapor erosion and the destabilization of large pore structures can easily result in pavement problems such as fragmentation, spalling, cracking, and excessive permanent deformation. To this end, four different preventive maintenance materials, including the rejuvenation (RJ), cohesion reinforcement (CEM), polymerization reaction, and emulsified asphalt (EA) types, were selected in this paper to improve the high-viscosity porous asphalt pavement. The effects of the different preventive maintenance materials on the temperature sensitivity, rheological properties and fatigue performance of high-viscosity modified asphalt were evaluated through temperature sweep, frequency sweep, multi-stress creep recovery (MSCR), linear amplitude sweep (LAS), and bending beam rheometer (BBR) tests. The results showed that the four preventive maintenance materials exhibit different enhancement mechanisms and effects. RJ improves the fatigue properties, deformation resistance and low-temperature cracking resistance of aged asphalt by adding elastomeric components; CEM materials are more conducive to increasing the low-temperature crack resistance of aged asphalt; while GL1 and EA improve the viscoelastic behavior of aged asphalt, but the effect of the dosing ratio needs to be considered.

18.
Ecol Evol ; 14(8): e70202, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39184570

RESUMEN

The development of hydroelectric projects has adversely affected the reproductive activities of downstream fish species. To facilitate the natural reproduction of fish and restore spawning grounds post-dam construction, it is imperative to explore the ecological factors crucial for their reproduction. Currently, various research methods with different advantages and limitations are employed for this purpose. Using identified spawning locations and periods as clues, we quantitatively investigate the flow velocity, water depth, water temperature, and riverbed substrate required for spawning. The results are validated using habitat simulation methods, aiming to establish a more scientific approach to explore ecological factors affecting fish reproduction. This study provides a more scientific, systematic, and detailed report on the ecological factors required for the spawning of Gymnocypris eckloni: flow velocity ranging from 0.19 to 0.97 m/s, water depth from 0.28 to 1.12 m, water temperature between 11.4 and 15.2°C, and predominantly gravel substrate. The reliability of the results was verified in another spawning ground, with good verification results. This research provides crucial data for the bio-mimetic reproductive technology of Gymnocypris eckloni and the restoration of spawning grounds for natural fish reproduction post-dam construction. It addresses the lack of suitable ecological factor data for protective fish species in the upper reaches of the Yellow River. The method exhibits strong scientific, accurate, and implementable characteristics.

19.
Front Med ; 18(5): 831-849, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39115793

RESUMEN

SETD2 is the only enzyme responsible for transcription-coupled histone H3 lysine 36 trimethylation (H3K36me3). Mutations in SETD2 cause human diseases including cancer and developmental defects. In mice, Setd2 is essential for embryonic vascular remodeling. Given that many epigenetic modifiers have recently been found to possess noncatalytic functions, it is unknown whether the major function(s) of Setd2 is dependent on its catalytic activity or not. Here, we established a site-specific knockin mouse model harboring a cancer patient-derived catalytically dead Setd2 (Setd2-CD). We found that the essentiality of Setd2 in mouse development is dependent on its methyltransferase activity, as the Setd2CD/CD and Setd2-/- mice showed similar embryonic lethal phenotypes and largely comparable gene expression patterns. However, compared with Setd2-/-, the Setd2CD/CD mice showed less severe defects in allantois development, and single-cell RNA-seq analysis revealed differentially regulated allantois-specific 5' Hoxa cluster genes in these two models. Collectively, this study clarifies the importance of Setd2 catalytic activity in mouse development and provides a new model for comparative study of previously unrecognized Setd2 functions.


Asunto(s)
Desarrollo Embrionario , N-Metiltransferasa de Histona-Lisina , Mutación , Animales , Ratones , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Desarrollo Embrionario/genética , Humanos , Modelos Animales de Enfermedad , Femenino
20.
Opt Express ; 21(21): 24497-503, 2013 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-24150295

RESUMEN

The exciton localization in wurtzite AlxGa1-xN alloys with x varying from 0.41 to 0.63 has been studied by deep-ultraviolet photoluminescence (PL) spectroscopy and picosecond time-resolved PL spectroscopy. Obvious S-shape temperature dependence was observed indicating that the strong exciton localization can be formed in high Al composition AlxGa1-xN alloys. It was also found that the Al composition dependence of exciton localization energy of AlGaN alloys is inconsistent with that of the excitonic linewidth. We contribute the inconsistency to the strong zero-dimensional exciton localization.

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