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1.
Microorganisms ; 12(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38674619

RESUMEN

Cefotaxime (CTX) is an easily detectable antibiotic pollutant in the water environment, but little is known about its toxic effects on aquatic invertebrates, especially on the intestine. Here, we determined the oxidative stress conditions of A. sinica under CTX exposure with five concentrations (0, 0.001, 0.01, 0.1 and 1 mg/L) for 14 days. After that, we focused on changes in intestinal tissue morphology and gut microbiota in A. sinica caused by CTX exposure at 0.01 mg/L. We found malondialdehyde (MDA) was elevated in CTX treatment groups, suggesting the obvious antibiotic-induced oxidative stress. We also found CTX exposure at 0.01 mg/L decreased the villus height and muscularis thickness in gut tissue. The 16S rRNA gene analysis indicated that CTX exposure reshaped the gut microbiota diversity and community composition. Proteobacteria, Actinobacteriota and Bacteroidota were the most widely represented phyla in A. sinica gut. The exposure to CTX led to the absence of Verrucomicrobia in dominant phyla and an increase in Bacteroidota abundance. At the genus level, eleven genera with an abundance greater than 0.1% exhibited statistically significant differences among groups. Furthermore, changes in gut microbiota composition were accompanied by modifications in gut microbiota functions, with an up-regulation in amino acid and drug metabolism functions and a down-regulation in xenobiotic biodegradation and lipid metabolism-related functions under CTX exposure. Overall, our study enhances our understanding of the intestinal damage and microbiota disorder caused by the cefotaxime pollutant in aquatic invertebrates, which would provide guidance for healthy aquaculture.

2.
Clin Cardiol ; 47(4): e24264, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563389

RESUMEN

BACKGROUND: Recently, patients with type 2 diabetes mellitus (T2DM) have experienced a higher incidence and severer degree of vascular calcification (VC), which leads to an increase in the incidence and mortality of vascular complications in patients with T2DM. HYPOTHESIS: To construct and validate prediction models for the risk of VC in patients with T2DM. METHODS: Twenty-three baseline demographic and clinical characteristics were extracted from the electronic medical record system. Ten clinical features were screened with least absolute shrinkage and selection operator method and were used to develop prediction models based on eight machine learning (ML) algorithms (k-nearest neighbor [k-NN], light gradient boosting machine, logistic regression [LR], multilayer perception [(MLP], Naive Bayes [NB], random forest [RF], support vector machine [SVM], XGBoost [XGB]). Model performance was evaluated using the area under the receiver operating characteristic curve (AUC), accuracy, and precision. RESULTS: A total of 1407 and 352 patients were retrospectively collected in the training and test sets, respectively. Among the eight models, the AUC value in the NB model was higher than the other models (NB: 0.753, LGB: 0.719, LR: 0.749, MLP: 0.715, RF: 0.722, SVM: 0.689, XGB:0.707, p < .05 for all). The k-NN model achieved the highest sensitivity of 0.75 (95% confidence interval [CI]: 0.633-0.857), the MLP model achieved the highest accuracy of 0.81 (95% CI: 0.767-0.852) and specificity of 0.875 (95% CI: 0.836-0.912). CONCLUSIONS: This study developed a predictive model of VC based on ML and clinical features in type 2 diabetic patients. The NB model is a tool with potential to facilitate clinicians in identifying VC in high-risk patients.


Asunto(s)
Diabetes Mellitus Tipo 2 , Calcificación Vascular , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Estudios Retrospectivos , Teorema de Bayes , Calcificación Vascular/diagnóstico , Calcificación Vascular/epidemiología , Calcificación Vascular/etiología , Aprendizaje Automático
3.
BMC Psychiatry ; 24(1): 124, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355472

RESUMEN

BACKGROUND: This study examined the association between social support and the severity of positive symptoms in rural community-dwelling schizophrenia patients during the COVID-19 pandemic. METHOD: The cross-sectional study included 665 rural community-dwelling schizophrenia patients investigated during the COVID-19 pandemic. Social support was measured using the Social Support Rating Scale, and positive symptoms were assessed using the Positive Scale extracted from the Positive and Negative Syndrome Scale. Multiple linear regression was adopted to examine the association of social support with positive symptoms. RESULT: The scores for total social support, subjective support, objective support and the use of social support were 28.3 ± 5.9, 16.4 ± 5.2, 6.5 ± 1.4 and 5.4 ± 2.8, respectively. Total social support (ß = -0.08, 95%CI: -0.13 to -0.02, P < 0.01) and subjective social support (ß = -0.10, 95%CI: -0.16 to -0.04, P < 0.01) were significantly and negatively associated with the Positive Scale score after adjustment for confounders. Objective social support (ß = 0.11, 95%CI: -0.10 to 0.32, P = 0.31) and the use of social support (ß = -0.03, 95%CI: -0.14 to 0.07, P = 0.53) were not significantly associated with the Positive Scale score. CONCLUSION: The study confirmed the importance of social support, especially subjective support, provided to rural community-dwelling schizophrenia patients during the COVID-19 pandemic. This support should be addressed and strengthened for such patients in emergent events.


Asunto(s)
COVID-19 , Esquizofrenia , Humanos , Vida Independiente , Esquizofrenia/epidemiología , Estudios Transversales , Pandemias , Apoyo Social
4.
Biomed Pharmacother ; 173: 116329, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38401518

RESUMEN

Benzodiazepines have been long-established treatments for various conditions, including anxiety disorders and insomnia. Recent FDA warnings emphasize the risks of misuse and dependence associated with benzodiazepines. This article highlights their benefits and potential drawbacks from various perspectives. It achieves this by explaining how benzodiazepines work in terms of neuroendocrinology, immunomodulation, sleep, anxiety, cognition, and addiction, ultimately improving their clinical effectiveness. Benzodiazepines play a regulatory role in the HPA axis and impact various systems, including neuropeptide Y and cholecystokinin. Benzodiazepines can facilitate sleep-dependent memory consolidation by promoting spindle wave activity, but they can also lead to memory deficits in older individuals due to reduced slow-wave sleep. The cognitive effects of chronic benzodiazepines use remain uncertain; however, no adverse findings have been reported in clinical imaging studies. This article aims to comprehensively review the evidence on benzodiazepines therapy, emphasizing the need for more clinical studies, especially regarding long-term benzodiazepines use.


Asunto(s)
Benzodiazepinas , Medicina de Precisión , Humanos , Anciano , Benzodiazepinas/efectos adversos , Sistema Hipotálamo-Hipofisario , Sistema Hipófiso-Suprarrenal , Ansiedad/tratamiento farmacológico
5.
Fish Shellfish Immunol ; 147: 109423, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38341117

RESUMEN

Cystatins comprise a vast superfamily of evolutionary conserved proteins, predominantly recognized for their roles as endogenous inhibitors by regulating the activity of cysteine proteases. Emerging lines of research evidence also provides insight into their alternative roles in a spectrum of biological and pathological processes, including neurodegenerative disorders, tumor progression, inflammatory diseases, and immune response. Nowadays, various type-1 cystatins (stefins) have been demonstrated among a variety of discovered vertebrate groups, while little is known about the related homologue in cephalochordate amphioxus, which are repositioned at the base of the chordate phylum. In the present study, a single type-1 cystatin homologue in Branchiostoma japonicum was first successfully cloned and designated as Bjcystatin-1. The deduced Bjcystatin-1 protein is structurally characterized by the presence of typical wedge-shaped cystatin features, including the 'QxVxG' and 'Px' motif, as well as the conserved N-terminal glycine residue. Phylogenomic analyses utilizing different cystatin counterparts affirmed the close evolutionary relationship of Bjcystatin-1 and type-1 cystatin homologue. Bjcystatin-1 was predominantly expressed in the gills and hind-gut in a tissue-specific pattern, and its expression was remarkably up-regulated in response to challenge with bacteria or their signature molecules LPS and LTA, suggesting the involvement in immune response. Additionally, the recombinant Bjcystatin-1 (rBjcystatin-1) protein showed significant inhibitory activity towards papain and binding ability to LPS and LTA, indicating its hypothesized role as a pattern recognition receptor in immune response. Subcellular localization results also showed that Bjcystatin-1 was located in the cytoplasm and nucleus, and its overexpression could attenuate the activation of LPS-induced nuclear transcription factors NF-κB. Taken together, our study suggests that amphioxus Bjcystatin-1 acts as a dual role in protease inhibitor and an immunocompetent factor, providing new insights into the immune defense effect of type-1 cystatin in amphioxus.


Asunto(s)
Cistatinas , Anfioxos , Animales , Lipopolisacáridos , Cistatinas/genética , Evolución Biológica , Factores de Transcripción
6.
Pharmacol Res ; 200: 107054, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38181858

RESUMEN

Diabetes, characterized as a well-known chronic metabolic syndrome, with its associated complications pose a substantial and escalating health and healthcare challenge on a global scale. Current strategies addressing diabetes are mainly symptomatic and there are fewer available curative pharmaceuticals for diabetic complications. Thus, there is an urgent need to identify novel pharmacological targets and agents. The impaired mitochondria have been associated with the etiology of diabetes and its complications, and the intervention of mitochondrial dysfunction represents an attractive breakthrough point for the treatments of diabetes and its complications. Natural products (NPs), with multicenter characteristics, multi-pharmacological activities and lower toxicity, have been caught attentions as the modulators of mitochondrial functions in the therapeutical filed of diabetes and its complications. This review mainly summarizes the recent progresses on the potential of 39 NPs and 2 plant-extracted mixtures to improve mitochondrial dysfunction against diabetes and its complications. It is expected that this work may be useful to accelerate the development of innovative drugs originated from NPs and improve upcoming therapeutics in diabetes and its complications.


Asunto(s)
Productos Biológicos , Complicaciones de la Diabetes , Diabetes Mellitus , Enfermedades Mitocondriales , Humanos , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Productos Biológicos/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Complicaciones de la Diabetes/tratamiento farmacológico , Complicaciones de la Diabetes/metabolismo , Mitocondrias/metabolismo , Enfermedades Mitocondriales/metabolismo , Estudios Multicéntricos como Asunto
7.
J Chem Theory Comput ; 19(15): 4851-4862, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37233199

RESUMEN

We present a quantum algorithm based on the generalized quantum master equation (GQME) approach to simulate open quantum system dynamics on noisy intermediate-scale quantum (NISQ) computers. This approach overcomes the limitations of the Lindblad equation, which assumes weak system-bath coupling and Markovity, by providing a rigorous derivation of the equations of motion for any subset of elements of the reduced density matrix. The memory kernel resulting from the effect of the remaining degrees of freedom is used as input to calculate the corresponding non-unitary propagator. We demonstrate how the Sz.-Nagy dilation theorem can be employed to transform the non-unitary propagator into a unitary one in a higher-dimensional Hilbert space, which can then be implemented on quantum circuits of NISQ computers. We validate our quantum algorithm as applied to the spin-boson benchmark model by analyzing the impact of the quantum circuit depth on the accuracy of the results when the subset is limited to the diagonal elements of the reduced density matrix. Our findings demonstrate that our approach yields reliable results on NISQ IBM computers.

8.
Chemosphere ; 334: 138993, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37244548

RESUMEN

Vacuum ultraviolet (VUV) based advanced oxidation processes (AOPs) recently attracted widespread interests. However, the role of UV185 in VUV is only considered to be generating a series of active species, while the effect of photoexcitation has long been overlooked. In this work, the role of UV185 induced high-energy excited state for the dephosphorization of organophosphorus pesticides was studied using malathion as a model. Results showed malathion degradation was highly related to radical yield, while its dephosphorization was not. It was UV185 rather than UV254 or radical yield that was responsible for malathion dephosphorization by VUV/persulfate. DFT calculation results demonstrated that the polarity of P-S bond was further increased during UV185 excitation, favoring dephosphorization while UV254 did not. The conclusion was further supported by degradation path identification. Moreover, despite the fact that anions (Cl-, SO42- and NO3-) considerably affected radical yield, only Cl- and NO3- with high molar extinction coefficient at 185 nm significantly affected dephosphorization. This study shed light on the crucial role of excited states in VUV based AOPs and provided a new idea for the development of mineralization technology of organophosphorus pesticides.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Compuestos Organofosforados , Malatión , Vacio , Contaminantes Químicos del Agua/química , Rayos Ultravioleta , Oxidación-Reducción
9.
Patient Prefer Adherence ; 17: 249-257, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36721389

RESUMEN

Purpose: To probe into the needs and barriers underlying patients' participation in shared decision-making related to rehabilitation nursing for hemophilic arthropathy. Patients and Methods: The phenomenological research approach was adopted to conduct a series of semi-structured, in-depth interviews with 15 patients with hemophilic arthropathy undergoing rehabilitative treatments, 10 caregivers, and 7 healthcare providers from a hemophilia treatment center in Shanxi province, China. Colaizzi's seven-step method of data analysis was applied to organize, analyze, and extract the themes from the interview materials. Results: Three main themes emerged from the analysis: the status quo of the healthcare system (insufficient decision support systems and mismatch between healthcare providers' and patients' resources), circumstances of provider-patient interactions (lack of information exchange and unbalanced power structure between healthcare providers and patients), and patient-related factors influencing participation in decision-making (lack of self-efficacy, personal characteristics, family and social decision support, and attitude toward participation in decision-making). Conclusion: Participation in rehabilitation decision-making among patients with hemophilic arthropathy is affected by multiple barriers. Healthcare professionals should improve their understanding of shared decision-making, offer patients active guidance on participating in the decision-making process, prioritize their affective needs, and formulate professional and effective solutions to support shared decision-making as early as possible.

10.
Front Public Health ; 11: 1294360, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38186712

RESUMEN

Introduction: The COVID-19 pandemic, which began in the last quarter of 2019, has had a significant impact on urban transportation. With increasing demand for urban transport, the internal roads and public spaces of university campuses play an important role in facilitating commuting and communication between various functional zones. While considerable research has been conducted on route planning, pedestrian-vehicle segregation, and safety management in the internal transportation environment of university campuses, empirical investigations exploring barrier-free inclusive campus environment design and the subjective evaluation of road and public space users in the aftermath of the COVID-19 pandemic are lacking. Recent developments in travel behavior models and positive psychology have led to an increased focus on the correlation among subjective perceptions, attitudes, emotions, and commuting satisfaction in urban transportation and planning design. Methods: To elucidate this relationship, a study was conducted on the new campus of Central South University in Changsha, Hunan Province, China. Using 312 valid samples, a structural equation model was constructed to analyse the relationship between commuting satisfaction and the barrier-free environment perception of university students regarding the internal transportation environment of the campus. Results: The results revealed that individuals' instantaneous barrier-free environment perceptions and long-term established positive emotions had a significant positive effect on commuting satisfaction. Furthermore, positive emotions were found to mediate the relationship between commuting attitudes induced by COVID-19, barrier-free environment perceptions, and commuting satisfaction. Discussion: The results of this study provide a theoretical basis for the necessity of accessibility design in the post-COVID era. In addition, this study considers the perspective of users to provide ideas for the planning and construction of barrier-free campus environments that are based on convenient and inclusive design.


Asunto(s)
COVID-19 , Pandemias , Humanos , Transportes , COVID-19/epidemiología , Satisfacción Personal , Percepción
11.
Seizure ; 91: 278-286, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34252880

RESUMEN

PURPOSE: Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) are assessed as oxidative stress markers to determine the impact of oxidation on the levels of GSH-Px and SOD in patients with epilepsy (PWE) and healthy controls. METHODS: A meta-analysis was completed on twenty-nine published studies. A total of 636 PWE and 665 healthy controls, 303 PWE and 191 controls, and 22 PWE and 22 controls were included to study GSH-Px levels in erythrocytes, serum and plasma, respectively. For SOD studies, there were 610 PWE and 680 controls, 464 PWE and 382 controls, and 62 PWE with 77 controls for erythrocytes, serum and plasma, respectively. RESULTS: Meta-analysis showed that the erythrocyte SOD level was significantly lower in PWE than in healthy controls (SMD =-1.96; 95% CI [-2.93, -0.99]; P<0.0001). Moreover, the meta-analysis demonstrated that in serum and plasma, SOD levels in PWE were significantly lower than those in healthy controls (SMD =-1.47; 95% CI [-2.47, -0.48]; P<0.0001). Erythrocyte GSH-Px levels had a tendency to decrease in PWE compared with healthy controls (SMD =-0.31; 95% CI [-1.48, 0.85]; P=0.598), but the results showed no significant difference. CONCLUSION: Our results showed reduced SOD levels in erythrocytes, serum and plasma in PWE, which may be an indicator of oxidative damage in epilepsy. This is the first meta-analysis of circulating GSH-Px and SOD levels in PWE and healthy controls.


Asunto(s)
Epilepsia , Glutatión Peroxidasa/sangre , Superóxido Dismutasa/sangre , Eritrocitos/metabolismo , Humanos , Estrés Oxidativo
12.
Fish Shellfish Immunol ; 115: 35-42, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33785471

RESUMEN

Mitogen-activated protein kinase 4, MKK4, is a key upstream kinase in the JNK/p38 MAPK pathway that has been reported to participate in multiple immune responses. In this study, the gene that encodes ApMKK4 was isolated and identified from Artemia parthenogenetica. It was found to contain a 1134 bp open reading frame encoding 378 amino acids. The predicted protein contains D domain, DVD domain and kinase domain. Homology analysis revealed that ApMKK4 shares 38-69% identity with MKK4 homologs from other species. Results revealed that ApMKK4 was mainly expressed during early development of which highest at the gastrula stage. After challenged by Vibrio harveyi and Micrococcus lysodeikticus, ApMKK4 was remarkably upregulated at 10 and 103 cfu/mL bacterial concentrations, respectively. Through siRNAi, the transcript level of ApMKK4 was significantly decreased by 46-67%. Intriguingly, when the ApMKK4-knockdown nauplii faced with bacterial stimulation, the expression of ApMKK4 was completely restored in a short time. Moreover, this phenomenon also occurred in related antimicrobial peptide genes, ABF-1 and ABF-2. Our research reveals that ApMKK4 plays a pivotal role during early development and immune responses against bacterial infections.


Asunto(s)
Artemia/genética , Artemia/inmunología , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Perfilación de la Expresión Génica , MAP Quinasa Quinasa 4/química , MAP Quinasa Quinasa 4/genética , MAP Quinasa Quinasa 4/inmunología , Micrococcus/fisiología , Alineación de Secuencia , Vibrio/fisiología
13.
Entropy (Basel) ; 22(1)2020 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33285893

RESUMEN

Image fusion is a very practical technology that can be applied in many fields, such as medicine, remote sensing and surveillance. An image fusion method using multi-scale decomposition and joint sparse representation is introduced in this paper. First, joint sparse representation is applied to decompose two source images into a common image and two innovation images. Second, two initial weight maps are generated by filtering the two source images separately. Final weight maps are obtained by joint bilateral filtering according to the initial weight maps. Then, the multi-scale decomposition of the innovation images is performed through the rolling guide filter. Finally, the final weight maps are used to generate the fused innovation image. The fused innovation image and the common image are combined to generate the ultimate fused image. The experimental results show that our method's average metrics are: mutual information ( M I )-5.3377, feature mutual information ( F M I )-0.5600, normalized weighted edge preservation value ( Q A B / F )-0.6978 and nonlinear correlation information entropy ( N C I E )-0.8226. Our method can achieve better performance compared to the state-of-the-art methods in visual perception and objective quantification.

14.
Ecotoxicol Environ Saf ; 204: 111129, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32805505

RESUMEN

Anaerobic digestate has been widely used for agricultural activities as an organic fertilizer product. Dissolved organic matter (DOM) derived from anaerobic digestate plays a key role in the speciation, bioavailability and ultimate fate of metals that is related to agriculture and food safety as well as the soil environment. Hence, the binding properties of Cu, Pb and Zn with digestate DOM are investigated using two-dimensional correlation spectroscopy (2D-COS) in combination with ultraviolet absorption, synchronous fluorescence spectra (SFS) and Fourier transform infrared (FTIR) spectroscopy. The 2D absorption COS shows that the DOM at 200 nm is most susceptive with the addition of Pb, followed by Zn and Cu. The log-transformed absorption spectra can also obtain more valuable signals than that from conventional absorption spectra. The 2D-SFS-COS indicates that protein-like peak is more sensitive to the variation of the concentration of metal ions, and fulvic-like substances can preferentially interact with the three heavy metals (HMs). The 2D-FTIR-COS reveals that Cu(II) and Zn(II) ions can be bonded preferentially to the N-H of secondary amide (II), and phenolic OH groups shows a favorable binding with Pb(II). Humic-like peaks with Cu(II) and Zn(II) obtains relatively higher log KM values than fulvic- and protein-like substances. However, the proportion of initial fluorescence (f) for DOM-Cu(II) and DOM-Zn(II) decreased with an increase in wavelength. Protein-like materials have more fluorescent substances that can combine with Cu(II) and Zn(II). This study provides a guide for understanding the geochemical behavior of metal ions in agricultural soils when anaerobic digestate is applied as an organic fertilizer product.


Asunto(s)
Sustancias Húmicas/análisis , Estiércol/microbiología , Metales Pesados/química , Anaerobiosis , Animales , Pollos , Fertilizantes , Fluorescencia , Suelo/química , Espectrometría de Fluorescencia/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos
15.
J Chem Theory Comput ; 16(7): 4479-4488, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32421321

RESUMEN

In this work, we investigate the ability of different quasiclassical mapping Hamiltonian methods to simulate the dynamics of electronic transitions through conical intersections. The analysis is carried out within the framework of the linear vibronic coupling (LVC) model. The methods compared are the Ehrenfest method, the symmetrical quasiclassical method, and several variations of the linearized semiclassical (LSC) method, including ones that are based on the recently introduced modified representation of the identity operator. The accuracy of the various methods is tested by comparing their predictions to quantum-mechanically exact results obtained via the multiconfiguration time-dependent Hartree (MCTDH) method. The LVC model is found to be a nontrivial benchmark model that can differentiate between different approximate methods based on their accuracy better than previously used benchmark models. In the three systems studied, two of the LSC methods are found to provide the most accurate description of electronic transitions through conical intersections.

16.
J Chem Theory Comput ; 16(5): 2883-2895, 2020 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-32227993

RESUMEN

Quasi-classical mapping Hamiltonian methods have recently emerged as a promising approach for simulating electronically nonadiabatic molecular dynamics. The classical-like dynamics of the overall system within these methods makes them computationally feasible, and they can be derived based on well-defined semiclassical approximations. However, the existence of a variety of different quasi-classical mapping Hamiltonian methods necessitates a systematic comparison of their respective advantages and limitations. Such a benchmark comparison is presented in this paper. The approaches compared include the Ehrenfest method, the symmetrical quasi-classical (SQC) method, and five variations of the linearized semiclassical (LSC) method, three of which employ a modified identity operator. The comparison is based on a number of popular nonadiabatic model systems; the spin-boson model, a Frenkel biexciton model, and Tully's scattering models 1 and 2. The relative accuracy of the different methods is tested by comparing with quantum-mechanically exact results for the dynamics of the electronic populations and coherences. We find that LSC with the modified identity operator typically performs better than the Ehrenfest and standard LSC approaches. In comparison to SQC, these modified methods appear to be slightly more accurate for condensed phase problems, but for scattering models there is little distinction between them.

17.
J Hazard Mater ; 393: 122436, 2020 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-32151934

RESUMEN

The influence of digestate dissolved organic matter (DOM) on chemical behavior of soil heavy metals (HMs) in an abandoned copper mining areas was explored by fluorescence quenching titration and heavy metal extracting experiment. Five fluorescent components were obtained from digestate DOM by PARAFAC model combined with the EEM data. The stability constant (log KM) values were in the range of 4.95-5.53, 5.05-5.29, 5.21-6.00, and 4.12-4.75 for DOM-Cr(III), DOM-Cu(II), DOM-Fe(III) and DOM-Pb(II) complexes, respectively. Alcohols, ethers and esters in digestate DOM were preferentially combined with Fe(III), Cu(II) and Zn(II). However, phenolic hydroxyl groups were more likely to combine with Cr(III) and Pb(II). The speciation distribution of HMs indicated that mining resulted in a higher concentration of Cu(II) in the grassland soil (GS) than those in the agricultural soil (AS) and forest land soil (FS). Fe-Mn oxides and organic forms of Pb(II) increased dramatically due to mining. Digestate DOM extraction can increase the content of Cr(III), Fe(III) and Pb(II), and decrease the content of Cu(II) and Zn(II) in the AS, GS, and FS. However, the contents of HMs in the mining soil (MS) and slag soil (SS) decreased due to the application of digestate DOM, except for Cu(II) in the SS.

18.
J Clin Hypertens (Greenwich) ; 21(9): 1343-1349, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31381261

RESUMEN

Recently, the American Academy of Pediatrics (AAP) recommended 120/80 mm Hg as thresholds for identifying elevated blood pressure (BP) in adolescents aged 13-17 years. The authors aimed to compare the performance of the new definition in identifying elevated BP with traditional percentile-based definition. Data were obtained from the National Health and Nutrition Examination Survey 1999-2014, which included 7485 adolescents aged 13-17 years. Elevated BP was defined using the recommended (≥120/80 mm Hg) and traditional definition (≥90th percentile for sex, age, and height or 120/80 mm Hg) presented in AAP guideline. The prevalence of elevated BP was 15.7% and 17.2% using the recommended and traditional definition, respectively (P < .001). The recommended definition had high sensitivity (90.9%), perfect specificity (100.0%), perfect positive predictive value (100.0%), and very high negative predictive value (98.1%) compared with the traditional definition. The Kappa correlation coefficient between two definitions was 0.94 (P < .001). Similar results can be observed in subgroups across sex, age, and sex- and age-specific height percentile except for both sexes with young age and low height percentile. Generally, our results supported the use of the recommended definition for identifying elevated BP in adolescents.


Asunto(s)
Hipertensión/diagnóstico , Hipertensión/fisiopatología , Encuestas Nutricionales/métodos , Pediatría/organización & administración , Adolescente , Determinación de la Presión Sanguínea/métodos , Estatura , Índice de Masa Corporal , Enfermedades Cardiovasculares/epidemiología , Estudios de Casos y Controles , Estudios Transversales/métodos , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Valor Predictivo de las Pruebas , Prevalencia , Medición de Riesgo , Sensibilidad y Especificidad , Estados Unidos/epidemiología
19.
J Chem Phys ; 151(7): 074103, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438690

RESUMEN

The generalized quantum master equation (GQME) provides a powerful framework for simulating electronically nonadiabatic molecular dynamics. Within this framework, the effect of the nuclear degrees of freedom on the time evolution of the electronic reduced density matrix is fully captured by a memory kernel superoperator. In this paper, we consider two different procedures for calculating the memory kernel of the GQME from projection-free inputs obtained via the combination of the mapping Hamiltonian (MH) approach and the linearized semiclassical (LSC) approximation. The accuracy and feasibility of the two procedures are demonstrated on the spin-boson model. We find that although simulating the electronic dynamics by direct application of the two LSC-based procedures leads to qualitatively different results that become increasingly less accurate with increasing time, restricting their use to calculating the memory kernel leads to an accurate description of the electronic dynamics. Comparison with a previously proposed procedure for calculating the memory kernel via the Ehrenfest method reveals that MH/LSC methods produce memory kernels that are better behaved at long times and lead to more accurate electronic dynamics.

20.
Front Neurosci ; 13: 21, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30842720

RESUMEN

Extrapancreatic nerves project to pancreatic islets directly or converge onto intrapancreatic ganglia. Intrapancreatic ganglia constitute a complex information-processing center that contains various neurotransmitters and forms an endogenous neural network. Both intrapancreatic ganglia and extrapancreatic nerves have an important influence on pancreatic endocrine function. This review introduces the histomorphology, innervation, neurochemistry, and electrophysiological properties of intrapancreatic ganglia/neurons, and summarizes the modulatory effects of intrapancreatic ganglia and extrapancreatic nerves on endocrine function.

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