scholarly journals Evaluating Clouds in Long-Term Cloud-Resolving Model Simulations with Observational Data

2007 ◽  
Vol 64 (12) ◽  
pp. 4153-4177 ◽  
Author(s):  
Xiping Zeng ◽  
Wei-Kuo Tao ◽  
Minghua Zhang ◽  
Christa Peters-Lidard ◽  
Stephen Lang ◽  
...  

Abstract Two 20-day, continental midlatitude cases are simulated with a three-dimensional (3D) cloud-resolving model (CRM) and are compared to Atmospheric Radiation Measurement Program (ARM) data. Surface fluxes from ARM ground stations and a land data assimilation system are used to drive the CRM. This modeling evaluation shows that the model simulates precipitation well but overpredicts clouds, especially in the upper troposphere. The evaluation also shows that the ARM surface fluxes can have noticeable errors in summertime. Theoretical analysis reveals that buoyancy damping is sensitive to spatial smoothers in two-dimensional (2D) CRMs, but not in 3D ones. With this theoretical analysis and the ARM cloud observations as background, 2D and 3D simulations are compared, showing that the 2D CRM has not only rapid fluctuations in surface precipitation but also spurious dehumidification (or a decrease in cloud amount). The present study suggests that the rapid precipitation fluctuation and spurious dehumidification be attributed to the sensitivity of buoyancy damping to dimensionality.

2006 ◽  
Vol 19 (1) ◽  
pp. 139-149 ◽  
Author(s):  
Xiaoqing Wu ◽  
Stephen Guimond

Abstract Two-dimensional (2D) and three-dimensional (3D) cloud-resolving model (CRM) simulations are conducted to quantify the enhancement of surface sensible and latent heat fluxes by tropical precipitating cloud systems for 20 days (10–30 December 1992) during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE). The mesoscale enhancement appears to be analogous across both 2D and 3D CRMs, with the enhancement for the sensible heat flux accounting for 17% of the total flux for each model and the enhancement for the latent heat flux representing 18% and 16% of the total flux for 2D and 3D CRMs, respectively. The convection-induced gustiness is mainly responsible for the enhancement observed in each model simulation. The parameterization schemes of the mesoscale enhancement by the gustiness in terms of convective updraft, downdraft, and precipitation, respectively, are examined using each version of the CRM. The scheme utilizing the precipitation was found to yield the most desirable estimations of the mean fluxes with the smallest rms error. The results together with previous findings from other studies suggest that the mesoscale enhancement of surface heat fluxes by the precipitating deep convection is a subgrid process apparent across various CRMs and is imperative to incorporate into general circulation models (GCMs) for improved climate simulation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kiyoshi Masuyama ◽  
Tomoaki Higo ◽  
Jong-Kook Lee ◽  
Ryohei Matsuura ◽  
Ian Jones ◽  
...  

AbstractIn contrast to hypertrophic cardiomyopathy, there has been reported no specific pattern of cardiomyocyte array in dilated cardiomyopathy (DCM), partially because lack of alignment assessment in a three-dimensional (3D) manner. Here we have established a novel method to evaluate cardiomyocyte alignment in 3D using intravital heart imaging and demonstrated homogeneous alignment in DCM mice. Whilst cardiomyocytes of control mice changed their alignment by every layer in 3D and position twistedly even in a single layer, termed myocyte twist, cardiomyocytes of DCM mice aligned homogeneously both in two-dimensional (2D) and in 3D and lost myocyte twist. Manipulation of cultured cardiomyocyte toward homogeneously aligned increased their contractility, suggesting that homogeneous alignment in DCM mice is due to a sort of alignment remodelling as a way to compensate cardiac dysfunction. Our findings provide the first intravital evidence of cardiomyocyte alignment and will bring new insights into understanding the mechanism of heart failure.


2021 ◽  
Vol 7 (3) ◽  
pp. 209-219
Author(s):  
Iris J Holzleitner ◽  
Alex L Jones ◽  
Kieran J O’Shea ◽  
Rachel Cassar ◽  
Vanessa Fasolt ◽  
...  

Abstract Objectives A large literature exists investigating the extent to which physical characteristics (e.g., strength, weight, and height) can be accurately assessed from face images. While most of these studies have employed two-dimensional (2D) face images as stimuli, some recent studies have used three-dimensional (3D) face images because they may contain cues not visible in 2D face images. As equipment required for 3D face images is considerably more expensive than that required for 2D face images, we here investigated how perceptual ratings of physical characteristics from 2D and 3D face images compare. Methods We tested whether 3D face images capture cues of strength, weight, and height better than 2D face images do by directly comparing the accuracy of strength, weight, and height ratings of 182 2D and 3D face images taken simultaneously. Strength, height and weight were rated by 66, 59 and 52 raters respectively, who viewed both 2D and 3D images. Results In line with previous studies, we found that weight and height can be judged somewhat accurately from faces; contrary to previous research, we found that people were relatively inaccurate at assessing strength. We found no evidence that physical characteristics could be judged more accurately from 3D than 2D images. Conclusion Our results suggest physical characteristics are perceived with similar accuracy from 2D and 3D face images. They also suggest that the substantial costs associated with collecting 3D face scans may not be justified for research on the accuracy of facial judgments of physical characteristics.


Author(s):  
Alexei Chichinin ◽  
Christof Maul ◽  
Karl-Heinz Gericke

The photodissociation dynamics of PCl3 at 235 nm has been studied by monitoring ground state Cl(2P3/2) and spin-orbitally excited Cl(2P1/2) atoms by resonance enhanced multiphoton ionization(REMPI). Also, the PCl+n (n=0,1,2)...


2021 ◽  
pp. 039139882098680
Author(s):  
Xuefeng Zhang ◽  
Nan Wang ◽  
Yuhua Huang ◽  
Yan Li ◽  
Gang Li ◽  
...  

Background: Three-dimensional (3D) culture has been reported to increase the therapeutic potential of mesenchymal stem cells (MSCs). The present study assessed the therapeutic efficacy of extracellular vesicles (EVs) from 3D cultures of human placental MSCs (hPMSCs) for acute kidney injury (AKI). Methods: The supernatants from monolayer culture (2D) and 3D culture of hPMSCs were ultra-centrifuged for EVs isolation. C57BL/6 male mice were submitted to 45 min bilateral ischemia of kidney, followed by renal intra-capsular administration of EVs within a 72 h reperfusion period. Histological, immunohistochemical, and ELISA analyses of kidney samples were performed to evaluate cell death and inflammation. Kidney function was evaluated by measuring serum creatinine and urea nitrogen. The miRNA expression profiles of EVs from 2D and 3D culture of hPMSCs were evaluated using miRNA microarray analysis. Results: The 3D culture of hPMSCs formed spheroids with different diameters depending on the cell density seeded. The hPMSCs produced significantly more EVs in 3D culture than in 2D culture. More importantly, injection of EVs from 3D culture of hPMSCs into mouse kidney with ischemia-reperfusion (I/R)-AKI was more beneficial in protecting from progression of I/R than those from 2D culture. The EVs from 3D culture of hPMSCs were more efficient against apoptosis and inflammation than those from 2D culture, which resulted in a reduction in tissue damage and amelioration of renal function. MicroRNA profiling analysis revealed that a set of microRNAs were significantly changed in EVs from 3D culture of hPMSCs, especially miR-93-5p. Conclusion: The EVs from 3D culture of hPMSCs have therapeutic potential for I/R-AKI.


2021 ◽  
Author(s):  
Serge Marbacher ◽  
Matthias Halter ◽  
Deborah R Vogt ◽  
Jenny C Kienzler ◽  
Christian T J Magyar ◽  
...  

Abstract BACKGROUND The current gold standard for evaluation of the surgical result after intracranial aneurysm (IA) clipping is two-dimensional (2D) digital subtraction angiography (DSA). While there is growing evidence that postoperative 3D-DSA is superior to 2D-DSA, there is a lack of data on intraoperative comparison. OBJECTIVE To compare the diagnostic yield of detection of IA remnants in intra- and postoperative 3D-DSA, categorize the remnants based on 3D-DSA findings, and examine associations between missed 2D-DSA remnants and IA characteristics. METHODS We evaluated 232 clipped IAs that were examined with intraoperative or postoperative 3D-DSA. Variables analyzed included patient demographics, IA and remnant distinguishing characteristics, and 2D- and 3D-DSA findings. Maximal IA remnant size detected by 3D-DSA was measured using a 3-point scale of 2-mm increments. RESULTS Although 3D-DSA detected all clipped IA remnants, 2D-DSA missed 30.4% (7 of 23) and 38.9% (14 of 36) clipped IA remnants in intraoperative and postoperative imaging, respectively (95% CI: 30 [ 12, 49] %; P-value .023 and 39 [23, 55] %; P-value = <.001), and more often missed grade 1 (< 2 mm) clipped remnants (odds ratio [95% CI]: 4.3 [1.6, 12.7], P-value .005). CONCLUSION Compared with 2D-DSA, 3D-DSA achieves a better diagnostic yield in the evaluation of clipped IA. Our proposed method to grade 3D-DSA remnants proved to be simple and practical. Especially small IA remnants have a high risk to be missed in 2D-DSA. We advocate routine use of either intraoperative or postoperative 3D-DSA as a baseline for lifelong follow-up of clipped IA.


2021 ◽  
pp. 021849232110304
Author(s):  
Mehrnoush Toufan ◽  
Zahra Jabbary ◽  
Naser Khezerlou aghdam

Background To quantify valvular morphological assessment, some two-dimensional (2D) and three-dimensional (3D) scoring systems have been developed to target the patients for balloon mitral valvuloplasty; however, each scoring system has some potential limitations. To achieve the best scoring system with the most features and the least restrictions, it is necessary to check the degree of overlap of these systems. Also the factors related to the accuracy of these systems should be studied. We aimed to determine the correlation between the 2D Wilkins and real-time transesophageal three-dimensional (RT3D-TEE) scoring systems. Methods This cross-sectional study was performed on 156 patients with moderate to severe mitral stenosis who were candidates for percutaneous balloon valvuloplasty. To morphologic assessment of mitral valve, patients were examined by 2D-transthoracic echocardiography and RT3D-TEE techniques on the same day. Results A strong association was found between total Wilkins and total RT3D-TEE scores (r = 0.809, p < 0.001). The mean mitral valve area assessed by the 2D and 3D was 1.07 ± 0.25 and 1.03 ± 0.26, respectively, indicating a mean difference of 0.037 cm2 (p = 0.001). We found a strong correlation between the values of mitral valve area assessed by 2D and 3D techniques (r = 0.846, p < 0.001). Conclusion There is a high correlation between the two scoring systems in terms of evaluating dominant morphological features. Partially, mitral valve area overestimation in the 2D-transthoracic echocardiography and its inability to assess commissural involvement as well as its dependence on patient age were exceptions in this study.


2021 ◽  
Vol 8 (1) ◽  
pp. 11
Author(s):  
Sorel E. De Leon ◽  
Lana Cleuren ◽  
Zay Yar Oo ◽  
Paul R. Stoddart ◽  
Sally L. McArthur

Three-dimensional (3D) cell cultures have recently emerged as tools for biologically modelling the human body. As 3D models make their way into laboratories there is a need to develop characterisation techniques that are sensitive enough to monitor the cells in real time and without the need for chemical labels. Impedance spectroscopy has been shown to address both of these challenges, but there has been little research into the full impedance spectrum and how the different components of the system affect the impedance signal. Here we investigate the impedance of human fibroblast cells in 2D and 3D collagen gel cultures across a broad range of frequencies (10 Hz to 5 MHz) using a commercial well with in-plane electrodes. At low frequencies in both 2D and 3D models it was observed that protein adsorption influences the magnitude of the impedance for the cell-free samples. This effect was eliminated once cells were introduced to the systems. Cell proliferation could be monitored in 2D at intermediate frequencies (30 kHz). However, the in-plane electrodes were unable to detect any changes in the impedance at any frequency when the cells were cultured in the 3D collagen gel. The results suggest that in designing impedance measurement devices, both the nature and distribution of the cells within the 3D culture as well as the architecture of the electrodes are key variables.


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