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1.
Sci Rep ; 14(1): 22004, 2024 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-39317735

RESUMEN

Recent evidence has demonstrated that abnormal expression and regulation of circular RNA (circRNAs) are implicated in the development and progression of various tumors. The aim of this study was to investigate the effects of circ_SMA4 in Gastrointestinal Stromal Tumors (GISTs) malignant progression. Human circRNAs microarray analysis was conducted to identify differentially expressed (DE) circRNAs in GISTs. The effect of circ_SMA4 on cell proliferation, invasion, migration, and apoptosis was assessed in both in vitro and in vivo settings. Dual-luciferase reporter assay, RT-qPCR, Western-blot, and rescue assay were employed to confirm the interaction between circ_SMA4/miR-494-3p/ KIT axis. The results revealed that circ_SMA4 was significantly upregulated in GISTs, and exhibited high diagnostic efficiency with an AUC of 0.9824 (P < 0.01). circ_SMA4 promoted cell proliferation, invasion, migration, while inhibiting apoptosis in GISTs cells, both in vitro and in vivo. Silencing circ_SMA4 partially inhibited GISTs malignant progression. Additionally, circ_SMA4 acted as a competing endogenous RNA (ceRNA) by targeting miR-494-3p, and KIT was identified as a functional gene for miR-494-3p in GISTs. Furthermore, the results confirmed that circ_SMA4/miR-494-3p/ KIT axis plays a role in activating the JAK/STAT signaling pathway in GISTs. Therefore, for the first time, we have identified and emphasized that circ_SMA4 is significantly upregulated and plays an oncogenic role in GISTs by sponging miR-494-3p to activate the KIT/JAK/STAT pathway. These findings underscore circ_SMA4 may serve as a novel diagnostic biomarker and therapeutic target for GISTs.


Asunto(s)
Proliferación Celular , Progresión de la Enfermedad , Tumores del Estroma Gastrointestinal , Regulación Neoplásica de la Expresión Génica , Quinasas Janus , MicroARNs , ARN Circular , Factores de Transcripción STAT , Transducción de Señal , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Proliferación Celular/genética , Quinasas Janus/metabolismo , Quinasas Janus/genética , Factores de Transcripción STAT/metabolismo , Factores de Transcripción STAT/genética , Línea Celular Tumoral , Animales , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Movimiento Celular/genética , Masculino , Ratones , Femenino , Apoptosis/genética , Persona de Mediana Edad , Ratones Desnudos
2.
Immunopharmacol Immunotoxicol ; 46(5): 672-684, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39155607

RESUMEN

BACKGROUND: Hepatic ischemia reperfusion injury (IRI) is a common liver surgery complication. This study aims to explore the effect and potential mechanism of Sunitinib - a multi-target tyrosine kinase inhibitor - on hepatic IRI. METHODS: We established a hepatic IRI model using C57BL/6 mice, and integrated 40 mg/kg of Sunitinib, solely or combined with 100 µg/kg of coumermycin A1 (C-A1), in the treatment strategy. H&E staining, TUNEL assay, and detection of serum ALT and AST activities were used to assess liver damage. Further, ELISA kits and Western Blots were utilized to determine IL-1ß, TNF-α, IL-6, CXCL10, and CXCL2 levels. Primary macrophages, once isolated, were cultured in vitro with either 2 nM of Sunitinib, or Sunitinib in conjunction with 1 µM of C-A1, to gauge their influence on macrophage polarization. qPCR and Western blot were conducted to examine the level of p-STAT1/STAT1, p-STAT3/STAT3, p-JAK2/JAK2, and M1/M2 polarization markers. To quantify immune cell infiltration, we applied Immunofluorescence. RESULTS: Sunitinib pretreatment significantly alleviated liver injury and reduced p-STAT1/STAT1, p-STAT3/STAT3, p-JAK2/JAK2 levels. In vitro, Sunitinib treatment curbed M1 polarization induced by LPS + IFN-γ and bolstered M2 polarization triggered by IL-4. C-A1 application upregulated JAK2/STAT pathway phosphorylation and promoted LPS + IFN-γ-induced M1 polarization, which was reversed by Sunitinib treatment. In IL-4-stimulated macrophages, application of C-A1 activated the JAK2/STAT pathway and decreased M2-type macrophages, which was reversed by Sunitinib treatment either. CONCLUSION: Sunitinib is capable of guiding the polarization of macrophages toward an M2-type phenotype via the inhibition of the JAK2/STAT pathway, thereby exerting a protective effect on hepatic IRI.


Asunto(s)
Janus Quinasa 2 , Macrófagos , Ratones Endogámicos C57BL , Daño por Reperfusión , Transducción de Señal , Sunitinib , Animales , Janus Quinasa 2/metabolismo , Janus Quinasa 2/antagonistas & inhibidores , Sunitinib/farmacología , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Daño por Reperfusión/inmunología , Daño por Reperfusión/patología , Ratones , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/inmunología , Masculino , Transducción de Señal/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Factores de Transcripción STAT/metabolismo
3.
Diagnostics (Basel) ; 14(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38611660

RESUMEN

Clustered ring enhancement (CRE) is a new lexicon for non-mass enhancement (NME) of breast MR in the 5th BIRADS, indicating a high suspicion of malignancy. We wonder if the presence of CRE correlates with expression of prognostic molecular biomarkers of breast cancer. A total of 58 breast lesions, which MRI reported with NME, were collected between July 2013 and December 2018. The patterns of enhancement including CRE were reviewed and the pathological results with expression of molecular biomarkers were collected. The association between MRI NME, pathological, and IHC stain findings were investigated under univariate analysis. A total of 58 breast lesions were pathologically proven to have breast cancer, comprising 31 lesions with CRE and 27 lesions without CRE on breast MRI. The expression of the estrogen receptor (ER) (p = 0.017) and the progesterone receptor (PR) (p = 0.017) was significantly lower in lesions with CRE as compared with those without CRE. The expression of Ki-67 (≥25%) was significantly higher in lesions with CRE (p = 0.046). The lesions with CRE had a lower expression ratio of ER (50.71 ± 45.39% vs. 74.26 ± 33.59%, p = 0.028). Our study indicated that lesions with CRE may possess different features from those without CRE in molecular expression, bearing a more aggressive behavior.

4.
Biol Direct ; 19(1): 23, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500127

RESUMEN

BACKGROUND: This study seeks to investigate the impacts of Lactobacillus reuteri (L. reuteri) on hepatic ischemia-reperfusion (I/R) injury and uncover the mechanisms involved. METHODS: Mice in the I/R groups were orally administered low and high doses of L.reuteri (L.reuteri-low and L. reuteri-hi; 1 × 1010 CFU/d and 1 × 1011 CFU/d), for 4 weeks prior to surgery. Following this, mice in the model group were treated with an Nrf2 inhibitor (ML-385), palmitoylcarnitine, or a combination of both. RESULTS: After treatment with L. reuteri, mice exhibited reduced levels of serum aminotransferase (ALT), aspartate aminotransferase (AST), and myeloperoxidase (MPO) activity, as well as a lower Suzuki score and apoptosis rate. L. reuteri effectively reversed the I/R-induced decrease in Bcl2 expression, and the significant increases in the levels of Bax, cleaved-Caspase3, p-p65/p65, p-IκB/IκB, p-p38/p38, p-JNK/JNK, and p-ERK/ERK. Furthermore, the administration of L. reuteri markedly reduced the inflammatory response and oxidative stress triggered by I/R. This treatment also facilitated the activation of the Nrf2/HO-1 pathway. L. reuteri effectively counteracted the decrease in levels of beneficial gut microbiota species (such as Blautia, Lachnospiraceae NK4A136, and Muribaculum) and metabolites (including palmitoylcarnitine) induced by I/R. Likewise, the introduction of exogenous palmitoylcarnitine demonstrated a beneficial impact in mitigating hepatic injury induced by I/R. However, when ML-385 was administered prior to palmitoylcarnitine treatment, the previously observed effects were reversed. CONCLUSION: L. reuteri exerts protective effects against I/R-induced hepatic injury, and its mechanism may be related to the promotion of probiotic enrichment, differential metabolite homeostasis, and the Nrf2/HO-1 pathway, laying the foundation for future clinical applications.


Asunto(s)
Microbioma Gastrointestinal , Limosilactobacillus reuteri , Daño por Reperfusión , Ratones , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/uso terapéutico , Palmitoilcarnitina/uso terapéutico , Daño por Reperfusión/prevención & control , Daño por Reperfusión/tratamiento farmacológico , Isquemia
5.
Sci Rep ; 14(1): 5310, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438474

RESUMEN

Our study aimed to compare bone scintigraphy and dual-layer detector spectral CT (DLCT) with multiphase contrast enhancement for the diagnosis of osteoblastic bone lesions in patients with prostate cancer. The patients with prostate cancer and osteoblastic bone lesions detected on DLCT were divided into positive bone scintigraphy group (pBS) and negative bone scintigraphy group (nBS) based on bone scintigraphy. A total of 106 patients (57 nBS and 49 pBS) was included. The parameters of each lesion were measured from DLCT including Hounsfield unit (HU), 40-140 keV monochromatic HU, effective nuclear numbers (Zeff), and Iodine no water (InW) value in non-contrast phase (N), the arterial phase (A), and venous phase (V). The slope of the spectral curve at 40 and 100 keV, the different values of the parameters between A and N phase (A-N), V and N phase (V-N), and hybrid prediction model with multiparameters were used to differentiate pBS from nBS. Receiver operating characteristic analysis was performed to compare the area under the curve (AUC) for differentiating the pBS group from the nBS group. The value of conventional HU values, slope, and InW in A-N and V-N, and hybrid model were significantly higher in the pBS group than in the nBS group. The hybrid model of all significant parameters had the highest AUC of 0.988, with 95.5% sensitivity and 94.6% specificity. DLCT with arterial contrast enhancement phase has the potential to serve as an opportunistic screening tool for detecting positive osteoblastic bone lesions, corresponding to those identified in bone scintigraphy.


Asunto(s)
Enfermedades Óseas , Enfermedades de los Cartílagos , Yodo , Neoplasias de la Próstata , Masculino , Humanos , Detección Precoz del Cáncer , Tomografía Computarizada por Rayos X , Tamizaje Masivo , Neoplasias de la Próstata/diagnóstico por imagen , Cintigrafía
6.
Water Sci Technol ; 89(1): 20-37, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38214984

RESUMEN

Chlorophyll-a (Chl-a) is an important parameter in water bodies. Due to the complexity of optics in water bodies, it is difficult to accurately predict Chl-a concentrations in water bodies by current traditional methods. In this paper, using Sentinel-2 remote sensing images as the data source combined with measured data, taking Wuliangsu Lake as the study area, a new intelligent algorithm is proposed for prediction of Chl-a concentration, which uses the adaptive ant colony exhaustive optimization algorithm (A-ACEO) for feature selection and the gray wolf optimization algorithm (GWO) to optimize support vector regression (SVR) to achieve Chl-a concentration prediction. The ant colony optimization algorithm is improved to select remote sensing feature bands for Chl-a concentration by introducing relevant optimization strategies. The GWO-SVR model is built by optimizing SVR using GWO with the selected feature bands as input and comparing it with the traditional SVR model. The results show that the usage of feature bands selected by the presented A-ACEO algorithm as inputs can effectively reduce complexity and improve the prediction performance of the model, under the condition of the same model, which can provide valuable references for monitoring the Chl-a concentration in Wuliangsu Lake.


Asunto(s)
Monitoreo del Ambiente , Lagos , Clorofila A/análisis , Monitoreo del Ambiente/métodos , Clorofila , Algoritmos , Agua
7.
Medicine (Baltimore) ; 102(13): e33349, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37000048

RESUMEN

RATIONALE: This report documents the intracardiac migration of a hook wire in a 47-year-old male patient after computed tomography (CT)-guided percutaneous hook wire localization of pulmonary ground-glass opacities. PATIENT CONCERNS: The patient underwent CT-guided hook wire localization before video-assisted thoracoscopic surgery (VATS) wedge resection for a pulmonary nodule in the right upper lung field. However, the hook wire was not found in the specimen obtained from the wedge resection. A right upper lobectomy was performed to locate the hook wire; however, it was not found. DIAGNOSIS: A transesophageal echocardiogram was performed, and the hook wire was found in the left ventricle (LV). INTERVENTIONS: The patient subsequently underwent exploratory cardiotomy to remove the foreign body. The patient was admitted to the intensive care unit for postoperative care. OUTCOMES: Postoperatively, no complications were observed, and the patient was discharged from the hospital 7 days postoperatively. He received standard lung cancer treatment afterwards. LESSONS: The present case was unique because the hook wire migrated through the bloodstream from the pulmonary vein to the left atrium, before finally reaching the LV. Based on the patient preoperative CT images, the ground glass opacities were proximal to a 2.5 mm wide vein, which drained into the pulmonary vein. The proximity of the hook wire to a blood vessel was reportedly attributed to an increased risk of hook wire migration through the bloodstream. Hematogenous hook wire migration into the heart can result in fatal complications. Early diagnosis and timely removal of the hook wire are recommended to prevent the worsening of this complication.


Asunto(s)
Neoplasias Pulmonares , Nódulo Pulmonar Solitario , Masculino , Humanos , Persona de Mediana Edad , Nódulo Pulmonar Solitario/cirugía , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/etiología , Tomografía Computarizada por Rayos X/métodos , Cirugía Torácica Asistida por Video/métodos , Cuidados Posoperatorios
8.
Nat Microbiol ; 8(2): 347-359, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36737588

RESUMEN

Bacterial fitness depends on adaptability to changing environments. In rich growth medium, which is replete with amino acids, Escherichia coli primarily expresses protein synthesis machineries, which comprise ~40% of cellular proteins and are required for rapid growth. Upon transition to minimal medium, which lacks amino acids, biosynthetic enzymes are synthesized, eventually reaching ~15% of cellular proteins when growth fully resumes. We applied quantitative proteomics to analyse the timing of enzyme expression during such transitions, and established a simple positive relation between the onset time of enzyme synthesis and the fractional enzyme 'reserve' maintained by E. coli while growing in rich media. We devised and validated a coarse-grained kinetic model that quantitatively captures the enzyme recovery kinetics in different pathways, solely on the basis of proteomes immediately preceding the transition and well after its completion. Our model enables us to infer regulatory strategies underlying the 'as-needed' gene expression programme adopted by E. coli.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Proteoma/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Biosíntesis de Proteínas , Aminoácidos/metabolismo
9.
Math Biosci Eng ; 20(1): 383-401, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36650771

RESUMEN

Drugs are an important means to treat various diseases. They are classified into several classes to indicate their properties and effects. Those in the same class always share some important features. The Kyoto Encyclopedia of Genes and Genomes (KEGG) DRUG recently reported a new drug classification system that classifies drugs into 14 classes. Correct identification of the class for any possible drug-like compound is helpful to roughly determine its effects for a particular type of disease. Experiments could be conducted to confirm such latent effects, thus accelerating the procedures for discovering novel drugs. In this study, this classification system was investigated. A classification model was proposed to assign one of the classes in the system to any given drug for the first time. Different from traditional fingerprint features, which indicated essential drug properties alone and were very popular in investigating drug-related problems, drugs were represented by novel features derived from a large drug network via a well-known network embedding algorithm called Node2vec. These features abstracted the drug associations generated from their essential properties, and they could overview each drug with all drugs as background. As class sizes were of great differences, synthetic minority over-sampling technique (SMOTE) was employed to tackle the imbalance problem. A balanced dataset was fed into the support vector machine to build the model. The 10-fold cross-validation results suggested the excellent performance of the model. This model was also superior to models using other drug features, including those generated by another network embedding algorithm and fingerprint features. Furthermore, this model provided more balanced performance across all classes than that without SMOTE.


Asunto(s)
Algoritmos , Máquina de Vectores de Soporte
10.
Proc Natl Acad Sci U S A ; 119(20): e2201585119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35544692

RESUMEN

Many cellular activities in bacteria are organized according to their growth rate. The notion that ppGpp measures the cell's growth rate is well accepted in the field of bacterial physiology. However, despite decades of interrogation and the identification of multiple molecular interactions that connects ppGpp to some aspects of cell growth, we lack a system-level, quantitative picture of how this alleged "measurement" is performed. Through quantitative experiments, we show that the ppGpp pool responds inversely to the rate of translational elongation in Escherichia coli. Together with its roles in inhibiting ribosome biogenesis and activity, ppGpp closes a key regulatory circuit that enables the cell to perceive and control the rate of its growth across conditions. The celebrated linear growth law relating the ribosome content and growth rate emerges as a consequence of keeping a supply of ribosome reserves while maintaining elongation rate in slow growth conditions. Further analysis suggests the elongation rate itself is detected by sensing the ratio of dwelling and translocating ribosomes, a strategy employed to collapse the complex, high-dimensional dynamics of the molecular processes underlying cell growth to perceive the physiological state of the whole.


Asunto(s)
Escherichia coli , Guanosina Tetrafosfato , Extensión de la Cadena Peptídica de Translación , Ribosomas , Escherichia coli/citología , Escherichia coli/crecimiento & desarrollo , Guanosina Tetrafosfato/metabolismo , Ribosomas/metabolismo
11.
Cardiol Young ; 31(6): 1051-1053, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33558002

RESUMEN

Post-procedural right ventricular pseudoaneurysm is a rare but life-threatening complication of interventional catheterisation. We describe a 3-day-old newborn who underwent transcatheter intervention for pulmonary atresia with a complication of right ventricular pseudoaneurysms, and transcatheter embolisation of the pseudoaneurysms was performed at 3-week-old. It is the first described case that receives transcatheter closure of right ventricular pseudoaneurysms in a newborn with a favourable outcome.


Asunto(s)
Aneurisma Falso , Cardiopatías Congénitas , Atresia Pulmonar , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/etiología , Cateterismo Cardíaco/efectos adversos , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Recién Nacido , Atresia Pulmonar/cirugía , Resultado del Tratamiento
12.
Sensors (Basel) ; 21(1)2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33401444

RESUMEN

With the popularity of portable positioning devices, crowd-sourced trajectory data have attracted widespread attention, and led to many research breakthroughs in the field of road network extraction. However, it is still a challenging task to detect the road networks of old downtown areas with complex network layouts from high noise, low frequency, and uneven distribution trajectories. Therefore, this paper focuses on the old downtown area and provides a novel intersection-first approach to generate road networks based on low quality, crowd-sourced vehicle trajectories. For intersection detection, virtual representative points with distance constraints are detected, and the clustering by fast search and find of density peaks (CFDP) algorithm is introduced to overcome low frequency features of trajectories, and improve the positioning accuracy of intersections. For link extraction, an identification strategy based on the Delaunay triangulation network is developed to quickly filter out false links between large-scale intersections. In order to alleviate the curse of sparse and uneven data distribution, an adaptive link-fitting scheme, considering feature differences, is further designed to derive link centerlines. The experiment results show that the method proposed in this paper preforms remarkably better in both intersection detection and road network generation for old downtown areas.

13.
Artículo en Inglés | MEDLINE | ID: mdl-33505507

RESUMEN

OBJECTIVE: To compare the efficacy and safety of combination of Aidi injection and chemotherapy and chemotherapy alone in treatment of breast cancer. METHODS: The related control and randomized studies till August 1st, 2020, were retrieved in the database including PubMed, Embase, Cochrane Library, CNKI, CBM, Wang-Fang, and VIP. Primary outcomes were response rate (RR) and performance status (KPS) improvement rate; secondary outcomes were rate of adverse drug reactions (ADR) including myelosuppression, digestive tract reaction, liver dysfunction, and cardiac toxicity. Review Manager 5.3 was used in the present analysis. RESULTS: In total, 20 studies (18 articles) were included in the present analysis. RR (OR 1.76 (1.32, 2.35); p=0.0001) and KPS improvement rate (OR: 2.68 (1.34, 6.46); p=0.007) in Aidi injection plus chemotherapy group were significantly higher than those of chemotherapy alone group. Addition of Aidi injection significantly reduced the rate of myelosuppression, digestive tract reaction, leukocyte decrease, II-IV cardiac function abnormality, atrial dysrhythmia, ventricular arrhythmia, ST segment T wave inversion, and abnormal ECG (all p < 0.05). CONCLUSION: Aidi injection could increase the efficacy of chemotherapy, could reduce myelosuppression, digestive tract reaction, and cardiac toxicity induced by chemotherapy, and did not lead to additional toxicity and side effect. Therefore, it is an anticancer drug with good efficacy and low toxicity, worth further popularization.

14.
Front Neurol ; 12: 759869, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34975723

RESUMEN

Background: Blepharospasm (BSP) and hemifacial spasm (HFS) are both facial hyperkinesia however BSP is thought to be caused by maladaptation in multiple brain regions in contrast to the peripherally induced cause in HFS. Plausible coexisting pathophysiologies between these two distinct diseases have been proposed. Objectives: In this study, we compared brain resting state functional connectivity (rsFC) and quantitative thermal test (QTT) results between patients with BSP, HFS and heathy controls (HCs). Methods: This study enrolled 12 patients with BSP, 11 patients with HFS, and 15 HCs. All subjects received serial neuropsychiatric evaluations, questionnaires determining disease severity and functional impairment, QTT, and resting state functional MRI. Image data were acquired using seed-based analyses using the CONN toolbox. Results: A higher cold detection threshold was found in the BSP and HFS patients compared to the HCs. The BSP and HFS patients had higher rsFC between the anterior cerebellum network and left occipital regions compared to the HCs. In all subjects, impaired cold detection threshold in the QTT of lower extremities had a correlation with higher rsFC between the anterior cerebellar network and left lingual gyrus. Compared to the HCs, increased rsFC in right postcentral gyrus in the BSP patients and decreased rsFC in the right amygdala and frontal orbital cortex in the HFS subjects were revealed when the anterior cerebellar network was used as seed. Conclusions: Dysfunction of sensory processing detected by the QTT is found in the BSP and HSP patients. Altered functional connectivity between the anterior cerebellar network and left occipital region, especially the Brodmann area 19, may indicate the possibility of shared pathophysiology among BSP, HFS, and impaired cold detection threshold. Further large-scale longitudinal study is needed for testing this theory in the future.

15.
Environ Pollut ; 267: 115569, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33254687

RESUMEN

The threshold effect in the relationship between impervious surfaces and water quality has been a focus in past decades, but little attention has been paid to how the threshold effect changes during a rapid urbanization period. This study reveals the temporal variation of threshold effect in the relationship between the percentage of total impervious area (PTIA) and water quality indicators in a reticular river network area in Shanghai, China. The PTIA was surveyed and defined using the ISC method (impervious surface coefficients). A segmented regression model was used to disclose the non-linear relationship between PTIA and water quality. It is confirmed that the threshold effect was different in terms of water quality indicators, but the effect size became smaller as the threshold increased with urbanization level during the period of 1989-2010. Meteorological conditions make influence on the threshold effect, it can be found that the effect is more significant under higher air temperature conditions, while in the lower temperature situation, there is no significant threshold effect.


Asunto(s)
Urbanización , Calidad del Agua , Aire Acondicionado , China , Ríos
16.
Opt Express ; 28(16): 23679-23689, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32752361

RESUMEN

A potential technology applied in optical storage, the polarization holography has attracted much attention. In polarization holography, not only the amplitude and phase but also the polarization state is applied to record the information. What is meant by faithful reconstruction is that the reconstructed wave is identical to the signal wave. In the previously reported experiments about faithful reconstruction in orthogonal polarization holography, all the reading waves are identical to the reference waves of recording stage. It may result in a misunderstanding that the reading wave being identical to the reference wave of recording stage is the prerequisite for faithful reconstruction. We designed the experiments to observe the faithful reconstruction read by different polarized waves, where two orthogonal elliptically polarized waves are applied in the recording stage and phenanthrenequinone-doped poly methyl methacrylate (PQ/PMMA) is used as the recording material. By controlling the exposure time of recording material, the faithful reconstruction may be observed when the reading wave is the linearly polarized wave and the elliptically polarized wave, where neither reading wave is the same as the reference wave. The result may be of help for us to understand the reconstructed characteristics of orthogonal polarization holography.

17.
Environ Monit Assess ; 191(12): 771, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31773378

RESUMEN

Shanghai is one of the largest metropolitan areas in the world, during the rapid urbanization of the past decades, impervious surface expanded dramatically and became a main factor influencing surface water quality. Thus, exploring the driving forces of impervious surface has great implications in such metropolitan area. In this study, an impervious surface coefficient method (ISC) was used to measure the percentage of total impervious area (PTIA) of Shanghai; regression analysis was conducted to define the relationship between PTIA and three socio-economic factors, population density, unit area gross domestic product, and unit area industrial output at the city and district scale. Results showed that the industrial land use generated the highest ISC value, followed by high-density residential. Strong correlations were showed between PTIA and socio-economic indicators, in which population density was the most significant. Threshold effect was presented that when population density was higher than 15000 per/km2, this relationship would become less significant and PTIA remained stable. Similar effects were found when unit area gross domestic product exceeded 125 million yuan/km2. Scale effect was also discussed that the relationship was more significant at city scale than district. An improved understanding of the threshold effect and scale effect will help guide future urban planning and design new urban ecosystem policies.


Asunto(s)
Ecosistema , Propiedades de Superficie , Urbanización , China , Ciudades , Planificación de Ciudades , Movimientos del Agua
19.
Iran J Radiol ; 13(2): e19814, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27679690

RESUMEN

BACKGROUND: Traditional digital subtraction angiography (DSA) is currently the gold standard diagnostic method for the diagnosis and evaluation of cerebral arteriovenous malformation (AVM) and dural arteriovenous fistulas (dAVF). OBJECTIVES: The aim of this study was to analyze different less invasive magnetic resonance angiography (MRA) images, time-resolved MRA (TR-MRA) and three-dimensional time-of-flight MRA (3D TOF MRA) to identify their diagnostic accuracy and to determine which approach is most similar to DSA. PATIENTS AND METHODS: A total of 41 patients with AVM and dAVF at their initial evaluation or follow-up after treatment were recruited in this study. We applied time-resolved angiography using keyhole (4D-TRAK) MRA to perform TR-MRA and 3D TOF MRA examinations simultaneously followed by DSA, which was considered as a standard reference. Two experienced neuroradiologists reviewed the images to compare the diagnostic accuracy, arterial feeder and venous drainage between these two MRA images. Inter-observer agreement for different MRA images was assessed by Kappa coefficient and the differences of diagnostic accuracy between MRA images were evaluated by the Wilcoxon rank sum test. RESULTS: Almost all vascular lesions (92.68%) were correctly diagnosed using 4D-TRAK MRA. However, 3D TOF MRA only diagnosed 26 patients (63.41%) accurately. There were statistically significant differences regarding lesion diagnostic accuracy (P = 0.008) and venous drainage identification (P < 0.0001) between 4D-TRAK MRA and 3D TOF MRA. The results indicate that 4D-TRAK MRA is superior to 3D TOF MRA in the assessment of lesions. CONCLUSION: Compared with 3D TOF MRA, 4D-TRAK MRA proved to be a more reliable screening modality and follow-up method for the diagnosis of cerebral AVM and dAVF.

20.
Adv Mater ; 28(5): 951-8, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26638861

RESUMEN

Rigid fused perylene diimide (PDI) dimers bridged with heterocycles exhibit superior photovoltaic performance compared to their unfused semiflexible analogues. Changing the chalcogen atoms in the aromatic bridges gradually increases the twist angles between the two PDI planes, leading to a varied morphology in which the one bridged by thiophene achieves a balance and shows the best efficiency of 6.72%.

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