chamber size
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2021 ◽  
Author(s):  
Zu Biao Ren ◽  
Abdullah Akarim Al-Rabah ◽  
Antonio Pico ◽  
Michael Freeman

Abstract The challenge of Heavy oil thermal production Kuwait includes how to monitor steam flood effectiveness and cap rock integrity. Due to shallow & heterogeneous reservoirs and thin cap rock, pressurized and heated steam could diffuse in all directions and breach the cap rock. KOC acquired a baseline & time-lapsed surface seismic and 3D VSP for purposes of monitoring CSS production. This paper presents a technical application of seismic inversion to steam chamber size & cap rock integrity interpretation. The seismic image area includes 13 CSS wells, at varying CSS stages of steam injection, soaking and production. The data acquisition consisted of a base and a time-lapsed monitor seismic; each acquisition period lasting for around a week and separated by 40 day intervals. The simultaneous acquisition of surface seismic and the 3D VSP enabled complimentary data exchange and results validation. Well data of sonic and PHIT are used for building a low frequency inversion model. Rock physical modeling is also required to understand the effect of steam and production changes on acoustic and elastic properties. Various geophysical inversion methods are performed on AI inversion of post & pre stack seismic and Poisson's ratio inversion. To estimate reservoir temperature changes due to steam injection, the calibrated rock-physics model was utilized to relate the AI response to temperature change. The steam injection is expected to decrease acoustic impedance. The AI difference exhibits much wider impedance anomalies revealing steam chamber size and the production zone around the wells at various stages of the CSS cycle. Average temperature maps in reservoirs derived from rock-physical modeling also show temperature change around the wells. Inverted seismic attributes of acoustic impedance and temperature were used for study of cap rock integrity. Interpretation results of the steam size through AI and temperature analysis at reservoir and cap rock enable optimization of our CSS and SF completion strategies include steam pressure and volume, soaking period and thermal production control. The result of cap rock integrity monitoring also indicate no serious damage of cap rock under existing conditions of CSS operation (WHT: 420 °F & WHP: 320 PSI), which defines the limits of strategies to increase steam pressure and volume to increase EOR efficiency.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1572
Author(s):  
Rafa Tasnim ◽  
Yong-Jiang Zhang

Wild lowbush blueberries, an important fruit crop native to North America, contribute significantly to the economy of Maine, USA, Atlantic Canada, and Quebec. However, its photosynthetic capacity has not been well-quantified, with only a few studies showing its low photosynthetic rates. Its small leaves make accurate leaf-level photosynthetic measurements difficult and introduce potential uncertainties in using large leaf chambers. Here, we determined the photosynthetic rate for five different wild blueberry genotypes using a big leaf chamber enclosing multiple leaves and a small leaf chamber with a single leaf to test whether using big leaf chambers (branch-level measurements) underestimates the photosynthetic capacity. Photosynthetic rates of wild blueberries were significantly (35–47%) lower when using the big leaf chamber, and they are not a crop with low photosynthetic capacity, which can be as high as 16 μmol m−2 s−1. Additionally, wild blueberry leaves enclosed in the big chamber at different positions of a branch did not differ in chlorophyll content and photosynthetic rate, suggesting that the difference was not caused by variation among leaves but probably due to leaf orientations and self-shading in the big chamber. A significant linear relationship between the photosynthetic rate measured by the small and big leaf chambers suggests that the underestimation in leaf photosynthetic capacity could be corrected. Therefore, chamber-size effects need to be considered in quantifying photosynthetic capacity for small-leaf crops, and our study provided important guidelines for future photosynthesis research. We also established the relationship between the Electron Transport Rate (ETR) and photosynthetic CO2 assimilation for wild blueberries. ETR provides an alternative to quantify photosynthesis, but the correlation coefficient of the relationship (R2 = 0.65) suggests that caution is needed in this case.


2021 ◽  
Author(s):  
Julia R Mitchell ◽  
Sean G Trettel ◽  
Anna J Li ◽  
Sierra Wasielewski ◽  
Kylie A Huckleberry ◽  
...  

Pavlovian fear conditioning is a widely used behavioral paradigm for studying associative learning in rodents. Despite early recognition that subjects may engage in a variety of behaviors that reflect the experimental parameters of a given protocol, the last several decades have seen the field narrow its focus to measure freezing as the sole indicator of conditioned fear. Additionally, unconditioned responses such as shock-related activity are rarely considered. We previously reported that female Sprague Dawley rats are more likely than males to engage in darting, an escape-like conditioned response that is associated with heightened shock reactivity, but we did not establish whether darting was sensitive to manipulations of factors such as chamber size, shock intensity, or number of trials. Our goal here was to address these questions by defining parametric and phenotypic predictors of darting in both sexes. To better capture fear-related behavioral repertoires in our animals, we developed ScaredyRat, a custom Python tool that analyzes Noldus Ethovision-generated raw data files to identify Darters and quantify both conditioned and unconditioned responses. We find that like freezing, darting probability scales with experimental alterations in multiple dimensions. In most cases, the sex bias towards females persists, but males will transition to darting in extended, or overtraining fear conditioning protocols.


2021 ◽  
Vol 6 (5) ◽  

Background: Cardiac percussion (CP) is a bedside technique to evaluate cardiac borders and chamber size. Although advanced cardiac imaging has revolutionized the methods to detect cardiomegaly, art of CP remains the most convenient option, especially in emergent situations. Although transthoracic echocardiography (TTE) is considered the gold standard to determine left ventricular (LV) size, CP can estimate LV size with equal accuracy as TTE in appropriate clinical setting. The aim of this study was to investigate the correlation of LV size assessed by CP technique versus standard TTE, as well as cardiothoracic ratio (CTR) on chest roentgenography (CXR). Methods: This descriptive study was conducted on Telemetry units. Patients were positioned in supine position at Gatch angle of 30-45 degrees. Cardiac dullness was measured in cm by percussing from mid clavicular line towards gladiolus of sternal body. Subsequently, findings were correlated with TTE dimensions of left ventricular end-diastolic diameter (LVEDD). Results: In 200 patients, mean age was 63+15.8 years, with 51% females. The LV diameter (LVD) measured by CP technique was observed to be similar to LVEDD measured by TTE (Mean- 4.65+0.67 cm versus 4.69+0.76 cm, COV 7.6%). The BlandAltman comparison of CP technique and TTE measurements indicated significant differences in variances between the two measures (r=0.270, p=<0.001). The LVD measured by CXR did not show correlation with LVEDD (5.79+1.21 cm, COV 14.3%) with significant differences in the variances between the two measures (r=-0.475, p<0.001). The LV volumes measured by CP technique were observed to have correlation with LV volumes measured by TTE (COV 14.9%). Conclusion: CP technique is a convenient bedside method that can be utilized to assess LVD and volume. It is shown to have a precise correlation with LVEDD measured by TTE. The study emphasizes role of bedside estimation of LV size by using the art of physical examination.


Author(s):  
Annika Ingvarsson ◽  
Anna Werther Evaldsson ◽  
Johan Waktare ◽  
Oscar Braun ◽  
Gustav Jan Smith ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Guochen Duan ◽  
Boqiang Shi ◽  
Jie Gu

In order to reduce wear and increase crushing efficiency of the 6-DOF (degree of freedom) robotic crusher, the maximum single-particle compression ratio function of the granular material and the wear model of the mantle liner under eccentric compression are established. The function and model take into account the influence of crusher parameters and granular material parameters on maximum single-particle compression ratio, which is simulated by EDEM and obtained under different conditions. Combined with previous research, the theoretical distribution of crushed products and the crushing chamber size can be obtained at each time of the whole life cycle of the liner. Compared with the experimental data of Ansteel Group in previous research, the difference between the functional model and the actual results is small. This function is universal and can be used to provide reference for the 6-DOF robotic crusher’s crushing strategy and a theoretical basis and a design reference of the traditional structure cone crusher.


2021 ◽  
Vol 8 (2) ◽  
pp. 15
Author(s):  
Kendall E. Martin ◽  
Joshua S. Waxman

Proper development and function of the vertebrate heart is vital for embryonic and postnatal life. Many congenital heart defects in humans are associated with disruption of genes that direct the formation or maintenance of atrial and pacemaker cardiomyocytes at the venous pole of the heart. Zebrafish are an outstanding model for studying vertebrate cardiogenesis, due to the conservation of molecular mechanisms underlying early heart development, external development, and ease of genetic manipulation. Here, we discuss early developmental mechanisms that instruct appropriate formation of the venous pole in zebrafish embryos. We primarily focus on signals that determine atrial chamber size and the specialized pacemaker cells of the sinoatrial node through directing proper specification and differentiation, as well as contemporary insights into the plasticity and maintenance of cardiomyocyte identity in embryonic zebrafish hearts. Finally, we integrate how these insights into zebrafish cardiogenesis can serve as models for human atrial defects and arrhythmias.


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