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OBJECTIVES: The prognostic value of cardiac magnetic resonance feature tracking (CMR-FT)-derived right ventricular longitudinal strain (RVLS) post-heart transplantation has not been studied. This study aimed to evaluate the prognostic significance of CMR-FT-derived RVLS, in patients post- heart transplantation and to directly compare its value with that of conventional RV ejection fraction (RVEF). METHODS: In a cohort of consecutive heart transplantation recipients who underwent CMR for surveillance, RVLS from the free wall was measured by CMR-FT. The composite endpoint was all-cause death or major adverse cardiac events. The Cox regression model was used to examine the independent association between RVLS and the endpoint. RESULTS: A total of 96 heart transplantation recipients were retrospectively included. Over a median follow-up of 41 months, 20 recipients reached the composite endpoint. The multivariate Cox analysis showed that the model with RVLS (hazard ratio [HR]:1.334; 95% confidence interval [CI]:1.148 to 1.549; p < 0.001; Akaike information criterion [AIC] = 140, C-index = 0.831) was better in predicting adverse events than the model with RVEF (HR:0.928; 95% CI: 0.868 to 0.993; p = 0.030; AIC = 149, C-index = 0.751). Furthermore, receiver operating characteristic curves revealed that the accuracy for predicting adverse events was greater for RVLS than RVEF (area under the curve: 0.85 vs 0.76, p = 0.03). CONCLUSIONS: CMR-FT-derived RVLS is an independent predictor of adverse events in post-heart transplantation, and its predictive value was better than RVEF. Therefore, our study highlighted the importance of evaluating RVLS for risk stratification after heart transplantation. KEY POINTS: ⢠CMR-RVLS is an independent predictor of adverse events post-heart transplantation and provides greater predictive value. ⢠CMR-RVLS may help clinicians to risk stratification in heart transplantation recipients.
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Trasplante de Corazón , Disfunción Ventricular Derecha , Humanos , Pronóstico , Estudios Retrospectivos , Ventrículos Cardíacos/diagnóstico por imagen , Curva ROC , Volumen Sistólico , Valor Predictivo de las Pruebas , Función Ventricular Derecha , Imagen por Resonancia Cinemagnética/efectos adversos , Función Ventricular IzquierdaRESUMEN
Solid amine adsorbents are among the most promising CO2 adsorption technologies for biogas upgrading due to their high selectivity toward CO2, low energy consumption, and easy regeneration. However, in most cases, these adsorbents undergo severe chemical inactivation due to urea formation when regenerated under a realistic CO2 atmosphere. Herein, we demonstrated a facile and efficient synthesis route, involving the synthesis of nano-Al2O3 support derived from coal fly ash with a CO2 flow as the precipitant and the preparation of polyethylenimine (PEI)-impregnated Al2O3-supported adsorbent. The optimal 55%PEI@2%Al2O3 adsorbent showed a high CO2 uptake of 139 mg·g-1 owing to the superior pore structure of synthesized nano-Al2O3 support and exhibited stable cyclic stability with a mere 0.29% decay per cycle even under the realistic regenerated CO2 atmosphere. The stabilizing mechanism of PEI@nano-Al2O3 adsorbent was systematically demonstrated, namely, the cross-linking reaction between the amidogen of a PEI molecule and nano-Al2O3 support, owing to the abundant Lewis acid sites of nano-Al2O3. This cross-linking process promoted the conversion of primary amines into secondary amines in the PEI molecule and thus significantly enhanced the cyclic stability of PEI@nano-Al2O3 adsorbents by markedly inhibiting the formation of urea compounds. Therefore, this facile and efficient strategy for PEI@nano-Al2O3 adsorbents with anti-urea properties, which can avoid active amine content dilution from PEI chemical modification, is promising for practical biogas upgrading and various CO2 separation processes.
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Biocombustibles , Polietileneimina , Adsorción , Dióxido de Carbono , UreaRESUMEN
OBJECTIVES: To investigate whether cardiovascular magnetic resonance (CMR)-derived myocardial strains were abnormal in asymptomatic heart transplant (HT) patients with normal left ventricular ejection fraction (LVEF) and to detect the relationship between CMR-derived myocardial strain parameters and late gadolinium enhancement (LGE) in asymptomatic HT patients. METHODS: A total of 72 HT patients and 35 healthy volunteers underwent 1.5-T MR scanning. The examination protocol included basic cine imaging and LGE. The deformation registration algorithm (DRA) and feature tracking (FT) software were used for the strain analyses. Myocardial strain measurements included left ventricular global longitudinal strain (LVGLS), LV global circumferential strain (LVGCS), LV global radial strain (LVGRS) and right ventricular longitudinal strain (RVLS). RESULTS: Compared with healthy volunteers, HT patients had significantly decreased DRA- and FT- derived myocardial strain measurements (all p < 0.05). There was a significant correlation and high reproducibility between the DRA- and FT-derived strain parameters. Both CMR-derived LVGLS and LVGRS were significantly related to the presence of LGE, and multivariate logistic regression analyses showed that the LVGLS measurement obtained from both techniques was independently associated with the presence of LGE. The odds ratios (ORs) for DRA- and FT-LVGLS were 1.340 and 1.342, respectively. CONCLUSIONS: Asymptomatic HT patients with preserved LVEF exhibited reduced myocardial strain parameters. The CMR-derived LVGLS was independently related to the presence of LGE in HT patients. KEY POINTS: ⢠Reduced myocardial strain parameters were found in asymptomatic heart transplanted (HT) patients with normal left ventricular ejection fraction (LVEF). ⢠The deformation registration algorithm (DRA) and feature tracking (FT)-derived strains in asymptomatic HT patients had high reproducibility. ⢠DRA- and FT-derived LVGLS had an independent relationship with late gadolinium enhancement (LGE) in asymptomatic HT patients.
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Trasplante de Corazón , Ventrículos Cardíacos/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Adulto , Enfermedades Asintomáticas , Estudios de Casos y Controles , Medios de Contraste , Femenino , Gadolinio , Corazón , Ventrículos Cardíacos/fisiopatología , Humanos , Lógica , Imagen por Resonancia Cinemagnética/métodos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Miocardio , Reproducibilidad de los Resultados , Volumen Sistólico , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Derecha/fisiopatología , Función Ventricular IzquierdaRESUMEN
PURPOSE: Baraitser-Winter cerebrofrontofacial syndrome (BWCFF) is a rare autosomal dominant genetic disorder involving multiple organ systems and primarily characterized by structural brain abnormalities and a distinctive facial appearance. METHODS: To study the clinical characteristics, gene types and seizures of BWCFF. The natural history, clinical data and peripheral blood sample were collected in the child and his patients. To screen the ß-actin gene (ACTB) of a newly diagnosed child, hoping to find the gene mutation. RESULTS: The child had left ptosis, ocular hypertelorism, arched eyebrows, only 30% of the left ear hearing, a slight hypotonia, normal muscle strength, walking instability. The seizures were difficult to control with antiepileptic drugs and presented some degree of psychomotor development delay. Genetic screening showed De Novo in ACTB gene (c.484A> G, p.Thr162Ala). Parents did not detect related gene mutations. CONCLUSIONS: Patients with typical facial features and cerebral cortical malformations associated with refractory epilepsy should be highly suspected BWCFF. Patients are advised to carry out genetic screening to confirm the diagnosis.
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Epilepsia/complicaciones , Malformaciones del Sistema Nervioso/complicaciones , Actinas/genética , Niño , Análisis Mutacional de ADN , Electroencefalografía , Epilepsia/diagnóstico por imagen , Epilepsia/genética , Humanos , Imagen por Resonancia Magnética , Modelos Moleculares , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Malformaciones del Sistema Nervioso/genéticaRESUMEN
Amine-functionalized adsorbents offer substantial potential for CO2 capture owing to their selectivity and diverse application scenarios. However, their effectiveness is hindered by low efficiency and unstable cyclic performance. Here we introduce an amine-support system designed to achieve efficient and stable CO2 capture. Through atom-level design, each polyethyleneimine (PEI) molecule is precisely impregnated into the cage-like pore of MIL-101(Cr), forming stable composites via strong coordination with unsaturated Cr acid sites within the crystal lattice. The resulting adsorbent demonstrates a low regeneration energy (39.6 kJ/molCO2), excellent cyclic stability (0.18% decay per cycle under dry CO2 regeneration), high CO2 adsorption capacity (4.0 mmol/g), and rapid adsorption kinetics (15 min for saturation at 30 °C). These properties stem from the unique electron-level interaction between the amine and the support, effectively preventing carbamate products' dehydration. This work presents a feasible and promising cost-effective and sustainable CO2 capture strategy.
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Tubulin plays an essential role in cortical development, and TUBA1A encodes a major neuronal α-tubulin. Neonatal mutations in TUBA1A are associated with severe brain malformations, and approximately 70% of patients with reported cases of TUBA1A mutations exhibit lissencephaly. We report the case of a 1-year-old boy with the TUBA1A nascent mutation c.1204C >T, p.Arg402Cys, resulting in lissencephaly, developmental delay, and seizures, with a brain MRI showing normal cortical formation in the bilateral frontal lobes, smooth temporo-parieto-occipital gyri and shallow sulcus. This case has not been described in any previous report; thus, the present case provides new insights into the broad disease phenotype and diagnosis associated with TUBA1A mutations. In addition, we have summarized the gene mutation sites, neuroradiological findings, and clinical details of cases previously described in the literature and discussed the differences that exist between individual cases of TUBA1A mutations through a longitudinal comparative analysis of similar cases. The complexity of the disease is revealed, and the importance of confirming the genetic diagnosis from the beginning of the disease is emphasized, which can effectively shorten the diagnostic delay and help clinicians provide genetic and therapeutic counseling.
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The research on the high-value utilization of biomass has good application prospects and is conducive to sustainable development. In this paper, three different types of activators (potassium hydroxide, phosphoric acid, and polypropylene) were used to carbonize jujube branches at high temperatures of 600 °C and 800 °C, and then the PEG/jujube charcoal composite phase change materials (PCM) were prepared by vacuum impregnation of polyethylene glycol (PEG). The results showed that the carbon support activated by polypropylene (PP) had a richer pore size distribution than the other two activation methods, and the 800 °C carbonization carrier loaded PEG had a higher phase change enthalpy than the composite material at 600 °C. The mesoporous and macroporous structures were staggered with PP-activated jujube charcoal at 800 °C, with a specific surface area of 1082.2 m²/g, the melting enthalpy of the composite material reached 114.92 J/g, and the enthalpy of solidification reached 106.15 J/g after PEG loading. The diffraction peak of the composite phase change material was the superposition of PEG and carbon matrix, which proved that the loading process was physical adsorption. After 200 thermal cycles, the melting enthalpy and crystallization enthalpy were only reduced by 4.3% and 4.1%, respectively, and they remained stable and leak-free at the melting point of PEG for 2 h, demonstrating good thermal stability of the composite phase change materials. In summary, PP has obvious advantages over traditional activation, and the carbon-supported PEG phase change composite after PP activation is a biochar energy storage material with excellent performance.
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The serious phase separation in inorganic phase change materials, and easy leakage of organic phase change materials are the main obstacles to the practical batch application of phase change heat storage materials. To solve these problems, in this work, emulsion polymerization is introduced as the method for preparing organic-inorganic coupling phase change material (oic-PCM) with high heat storage performance using polyacrylamide (PAM) as the wall material and organic phase change material of cetyl alcohol as the core material, and diatomite is used as a supporting substrate to absorb inorganic sodium sulfate decahydrate (SSD). A differential scanning calorimeter (DSC), X-ray diffractometer (XRD), dust morphology and dispersion analyzer, and thermal conductivity tester were used to characterize the prepared organic-inorganic coupled phase change materials and investigate their performance. The research results show that when the mass fraction of cetyl alcohol is 68.97%, the mass fraction of emulsifier is 3.38%, and the mass fraction of sodium sulfate decahydrate/diatomite is 3.40%. The phase change latent heat of the organic-inorganic coupled phase change material is as high as 164.13 J/g, and the thermal conductivity reaches up to 0.2061 W/(m·k), which proves that the prepared organic-inorganic coupled phase change material has good heat storage performance, showing its good application prospects.
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The interaction between the terahertz wave propagating in free space and the sample is weak, which leads to the weak signal of the sample, which cannot meet the detection needs of trace samples. In order to meet the detection of trace samples, a kind of metamaterial absorber (the basic unit of the absorber is composed of gold-high resistance silicon-aluminum three-layer structure) is designed, and the monolayer graphene is transferred on the surface of the metamaterial absorber to construct the graphene-metamaterial absorber heterostructure. The transmission spectrum of the resonant cavity is simulated and measured by terahertz time domain spectroscopy system, and the obvious resonance frequency shift is observed. The results show that the graphene-metamaterial absorber heterostructure can detect josamycin antibiotic solution with concentration of 0.02 mg/L (the mass of josamycin is 0.2 ng). Compared with using the same structure metamaterial absorber to detect josamycin antibiotics, the sensitivity is increased by an order of magnitude. Using graphene-metamaterial heterostructure to detect the relative change of heterostructure reflectivity caused by josamycin antibiotics can reach 40%. The research in this paper provides a new technical means for accurate and rapid detection in terahertz band.
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Técnicas Biosensibles , Grafito , Antibacterianos , Simulación por Computador , Grafito/química , Josamicina , Materiales Manufacturados , Modelos Teóricos , Refractometría/métodos , Dispersión de RadiaciónRESUMEN
Peroxymonosulfate (PMS)-based Fenton-like reactions are widely used for wastewater remediation. Metal-free carbonaceous activators can avoid the secondary pollution caused by metal leaching but often suffer from insufficient activity due to limited active centers and mass transfer barriers. Here, we prepared a series of heteroatom (N, S, F)-doped, highly porous carbonaceous materials (UC-X, X = N, S, F) by pyrolyzing UiO-66 precursors assembled by various organic ligands. Density functional theory calculations showed that the heteroatoms modulated the electronic structures of the carbon plane. UC-X exhibited significantly enhanced PMS activation capability compared with the undoped counterpart, in the efficiency order of UC-N > UC-S > UC-F > UC. UC-N (calcined at 1000°C) showed the best PMS activation, exceeding that of commonly used carbocatalysts. The prominent performance of UC-N originated from its unique porous structure and homogeneously dispersed graphitic N moieties. Trapping experiments and electron spin resonance showed a nonradical degradation pathway in the UC-N/PMS system, through which organics were oxidized by donating electrons to UC-N/PMS* metastable complexes. This work not only reports a universal way to access high-performance, metal-free PMS activators but also provides insight into the underlying mechanism of the carbon-activated PMS process.
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Carbono , Grafito , Electrónica , Ligandos , MetalesRESUMEN
Syngas production from biomass gasification is a promising technology, which is widely used in the chemical industry. Crop straw and red mud are typical agricultural and industrial wastes, respectively, which are cheap and widespread; however, they cause serious environmental pollution due to the open burning of straw and the toxicity and alkalinity of red mud. In the present work, we converted crop straw into syngas by chemical looping gasification using red mud as a sinter-resistant oxygen carrier. The reactivity of red mud, the syngas yields, and the air pollutant emissions under different conditions were systematically investigated through a thermo-gravimetric analyzer and mass spectrometer. Compared with pure Fe2O3, red mud can promote the syngas yields from crop straw gasification owing to the presence of inert Al2O3 and SiO2. Red mud can effectively reduce the emission of air pollutants owing to the presence of alkaline components such as CaO and Na2O. As the Fe2O3/fuel mass ratio increases, the syngas yield increases and the air pollutant emissions simultaneously reduce; whereas the syngas yield and the air pollutant emissions decrease with increasing heating rate. After calcination at high temperature, the structure of red mud remains stable with slight agglomeration, and can be easily regenerated. Therefore, the promising results provide a breakthrough for efficient utilization and disposal of both crop straw and red mud.
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Gases , Oxígeno , Biomasa , Dióxido de Silicio , TermogravimetríaRESUMEN
Metal-organic framework (MOF) derivatives have drawn considerable attention for applications in various fields. In this work, spindle-shaped Ce-TCPPs were assembled by a rapid microwave-assisted hydrothermal method. After thermal treatment at low temperature under a N2 atmosphere, the Ce-TCPPs were partially pyrolyzed and converted to a novel CeO2/N-doped carbon/Ce-TCPP nanocomposite. Compared to completely decomposed materials, these partially decomposed heterogeneous catalysts exhibited significantly higher photocatalytic activation ability toward PMS for the removal of organic pollutants (e.g., rhodamine B, methylene blue, methyl orange, tetracycline and oxytetracycline). For the optimized sample thermal treated at 450 °C, a 100 mL RhB solution (10 mg/L) can be removed within 20 min with the assistance of PMS under visible light. The significantly enhanced activity can be attributed to the effective spatial separation of photogenerated electrons and holes in the formed Z-scheme CeO2/N-doped carbon/Ce-TCPP system. This work may provide useful guidance for the design and fabrication of MOF-derived photocatalytic systems for environmental remediation.
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Contaminantes Ambientales , Catálisis , Luz , PeróxidosRESUMEN
Objective: This study aimed to: (1) evaluate the association between myocardial fibrosis (MF) quantified by extracellular volume fraction (ECV) and myocardial strain measured by two-dimensional (2D)- and three-dimensional speckle-tracking echocardiography (3D-STE) and (2) further investigate which strain parameter measured by 2D- and 3D-STE is the more robust predictor of MF in heart transplant (HT) recipients. Methods: A total of 40 patients with HT and 20 healthy controls were prospectively enrolled. Left ventricular (LV)-global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were measured by 2D- and 3D-STE. LV diffuse MF was defined by cardiovascular magnetic resonance (CMR)-ECV. Results: The HT recipients had a significantly higher native T1 and ECV than healthy controls (1043.8 ± 34.0 vs. 999.7 ± 19.7 ms, p < 0.001; 26.6 ± 2.7 vs. 24.3 ± 1.8%, p = 0.02). The 3D- and 2D-STE-LVGLS and LVGCS were lower (p < 0.005) in the HT recipients than in healthy controls. ECV showed a moderate correlation with 2D-LVGLS (r = 0.53, p = 0.002) and 3D-LVGLS (r = 0.60, p < 0.001), but it was not correlated with 2D or 3D-LVGCS, or LVGRS. Furthermore, 3D-LVGLS and 2D-LVGLS had a similar correlation with CMR-ECV (r = 0.60 vs. 0.53, p = 0.670). A separate stepwise multivariate linear analysis showed that both the 2D-LVGLS (ß = 0.39, p = 0.019) and 3D-LVGLS (ß = 0.54, p < 0.001) were independently associated with CMR-ECV. Conclusion: CMR marker of diffuse MF was present in asymptomatic patients with HT and appeared to be associated with decreased myocardial strain by echocardiography. Both the 2D- and 3D-LVGLS were independently correlated with diffuse LVMF, which may provide an alternative non-invasive tool for monitoring the development of adverse fibrotic remodeling during the follow-up of HT recipients.
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Teaching point: Barium granuloma is a rare but potentially risky complication of barium studies that should be prevented, especially in susceptible patients.
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Recycling of spent lithium-ion batteries (LIBs) has drawn considerable attention in recent years, as an economic solution to the resource shortage. Selective ammonia leaching is recognized as an economical and environment-friendly method, yet it is difficult to separate and reuse the valuable metals from the leachate. In this study, we proposed an NH3-(NH4)2CO3-Na2SO3 leaching system to selectively recover the valuable metals from commercial LiNixCoyMn1-x-yO2 (NCM) and spent NCM. For single-stage leaching, 79.1% of the lithium, 86.4% of the cobalt, and 85.3% of the nickel were selectively leached under optimal conditions, and a mere 1.45% of the manganese was dissolved in the solution. The leaching process in the NH3-(NH4)2CO3-Na2SO3 system was consistent with the surface chemical reaction control model. For multistage leaching, almost all metals (98.4% of the lithium, 99.4% of the cobalt, 97.3% of the nickel) could be leached and a high-purity (>99%) MnCO3 product was simultaneously obtained. The introduction of CO32- not only led to the production of MnCO3 with wide application prospects, but also greatly reduced the consumption of the reducing agent. This study is thus beneficial for recycling of the valuable metals and synthesis of the MnCO3 product from the spent LIBs.
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Litio , Manganeso , Amoníaco , Carbonatos , Suministros de Energía Eléctrica , Metales , ReciclajeRESUMEN
Background The current study aims to validate the accuracy of 3-dimensional speckle-tracking echocardiography (3D-STE) in evaluating biventricular functions against the accuracy of cardiac magnetic resonance (CMR) and to explore the comprehensive characteristics and normal values for 3D-biventricular functions in transplanted hearts. Methods and Results A cohort of 35 heart transplant (HT) patients underwent both 3D echocardiography and CMR examination to validate the accuracy of 3D-STE in evaluating biventricular functions (Protocol 1). Then, 3D-STE derived biventricular functions were compared between 46 HT patients and 46 non-HT controls (Protocol 2). Protocol 1, validated that 3D-STE showed excellent accuracy in evaluating biventricular functions of transplanted hearts against CMR. Protocol 2, revealed lower (normal range) 3D-biventricular ejection fractions in HT patients than in controls (P<0.001). 3D-left ventricular global longitudinal strain, left ventricular-global circumferential strain, left ventricular-global radial strain, left ventricular-global performance index and right ventricular free-wall longitudinal strain were all lower in the HT patients than in healthy controls (P<0.001). Further, these strain values were all good for differentiating between groups (areas under the curve: 0.80-0.94, P<0.001). Moreover, left ventricular-lateral-wall radial displacement was higher and septal-wall radial displacement was lower in the HT group than in control group (P<0.001). Conclusions Compared with cardiac magnetic resonance, 3D-STE can evaluate biventricular functions of transplanted hearts accurately; 3D-biventricular mechanical functions are reduced even in clinically well HT patients. The provided characteristics and appropriate normal values of biventricular functions can be the basis for detection of ventricular dysfunction during follow-ups and further studies on transplanted hearts.
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Ecocardiografía Tridimensional , Trasplante de Corazón/efectos adversos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Función Ventricular Izquierda , Función Ventricular Derecha , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/fisiopatologíaRESUMEN
Although the ultrasonic technique for measuring temperature distributions has drawn much attention in recent years, most studies that adopt this technique focus on two-dimensional (2D) systems. Mathematically, extending from 2D to 3D requires higher construction-performing algorithms, as well as more complicated, but extremely crucial, designs of ultrasonic transducer layouts. Otherwise the ill condition of governing-equation matrices will become more serious. Here, we aim at constructing 3D temperature distributions by using a network of properly-installed ultrasonic transducers that can be controlled to transmit and receive ultrasound. In addition, the proposed method is capable of performing this construction procedure in real time, thus monitoring transient temperature distributions and guarantee the safety of operations related to heating or burning. Numerical simulations include constructions for four kinds of temperature distributions, as well as corresponding qualitative and quantitative analyses. Finally, our study offers a guide in developing non-intrusive experimental methods that measure 3D temperature distributions in real time.
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Myocardial interstitial expansion seems to be fundamental to the process of adverse left ventricular remodeling. Recent evidence has shown that the extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) can be used as a noninvasive method to quantify myocardial interstitial volume in a range of heart diseases. Our aim was to determine whether ECV is increased in asymptomatic orthotopic heart transplant (HTx) patients and its associations with clinical features and T2 values, the elevation of which usually suggests myocardial edema. A group of asymptomatic cardiac transplant recipients and some healthy volunteers were invited to undergo a comprehensive CMR scan, including cine imaging, late gadolinium enhancement, T1 mapping and T2 mapping, from March to June in 2017. All quantitative measurements were averaged from the basal and mid short-axis slices. Fifty-eight recipients (mean age, 42.7 ± 11.5 years; 13 females), at a median of 1.8 years (0.3-6.3 years) after HTx, and 20 healthy volunteers (mean age, 39.5 ± 11.3 years; 5 females) underwent the CMR scan. We found that both the ECV and T2 values were higher in the post-HTx group (ECV: 26.7 ± 3.3 vs. 24.6 ± 2.5%, p = 0.008; T2: 47.7 ± 2.8 vs. 44.5 ± 1.6 ms, p < 0.001) than in the control group. ECV was moderately associated with organ ischemia time at the time of transplantation but not with the hemodynamics parameter or the time since transplantation at CMR. Additionally, a relatively strong correlation was observed between ECV and T2 (r = 0.7, p < 0.001). So, our conclusion is that CMR-derived ECV is increased and associated with peri-transplant ischemia time in asymptomatic HTx patients. And the strong correlation of ECV with elevated T2 indicates that myocardial edema may be an important part of the extracellular volume expansion after heart transplantation.
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Edema Cardíaco/diagnóstico por imagen , Trasplante de Corazón/efectos adversos , Imagen por Resonancia Cinemagnética , Adulto , Enfermedades Asintomáticas , Estudios de Casos y Controles , Medios de Contraste/administración & dosificación , Edema Cardíaco/patología , Edema Cardíaco/fisiopatología , Femenino , Fibrosis , Gadolinio DTPA/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Miocardio/patología , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Función Ventricular Izquierda , Remodelación Ventricular , Adulto JovenRESUMEN
Temperature distribution reconstruction is of critical importance for circular area, and an ultrasonic technique is investigated to meet this demand in this paper. Considering the particularity of circular area, algorithm based on Markov radial basis approximation and singular value decomposition is proposed, while ultrasonic transducers layout and division of measured area are properly designed. The reconstruction performance is validated via numerical experiments using different temperature distribution models, and is compared with algorithm based on least square method. To study the anti-interference, various noises are adding to the theoretical value of time-of-flight. Experiment results indicate that the proposed algorithm can reconstruct temperature distribution with higher accuracy and stronger anti-interference, while without the problem of algorithm based on least square method that its reconstructions will lose much temperature information near the edge of measured area.
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Enhanced desulfurizing flotation of low sulfur coal was investigated using sonoelectrochemical method. The supporting electrolyte used in this process was sodium chloride and the additive was anhydrous ethanol. The effects of treatment conditions on desulfurization were studied by a single-factor method. The conditions include anhydrous ethanol concentration, sodium chloride concentration, sonoelectrolytic voltage, sonoelectrolytic temperature, sonoelectrolytic time and coal sample granulometry. The optimal experimental conditions achieved for anhydrous ethanol concentration, sodium chloride concentration, sonoelectrolytic voltage, sonoelectrolytic temperature and sonoelectrolytic time are 1.7 mol L(-1), 5.1×10(-3) mol L(-1), 10 V, 70 °C, 50 min achieved for a -0.18 mm coal sample. Optimal conditions cause a sulfur reduction of up to 69.4%. The raw and treated coals were analyzed by infrared spectroscopy and a chemical method. Pyritic sulfur, organic sulfur, ash as well as moisture are partially removed. The combination of high sulfur reduction, high yield, as well as high ash reduction was obtained in the newly developed method of enhanced flotation by sonoelectrochemistry. Ultrasound irradiation promotes electron transfer efficiency and increases clean coal yield.