EXPRESS: Can arrows change the subjective perception of space? Exploring symbolic attention repulsion

The attention repulsion effect (ARE) refers to distortions in the perception of space for areas nearby the focus of attention. For instance, when attending to the right-hand side of the visual field, objects in central vision may appear as though they are shifted to the left. The phenomenon is likely caused by changes in visual cell functioning. To date, research on the ARE has almost exclusively used exogenous manipulations of attention. In contrast, research exploring endogenous attention repulsion has been mixed, and no research has explored the effects of non-predictive arrow cues on this phenomenon. This gap in the literature is unexpected, as symbolic attention appears to be a unique form of attentional orienting compared to endogenous and exogenous attention. Therefore, the current study explored the effects of symbolic orienting on spatial repulsion and compared it to an exogenously generated ARE. Across four experiments, both exogenous and symbolic orienting resulted in AREs; however, the magnitude of the symbolic ARE was smaller than the exogenous ARE. This difference in magnitude persisted, even after testing both phenomena using stimulus timing parameters known to produce optimal effects in traditional attentional cueing paradigms. Therefore, compared to symbolic attention, it appears that exogenous manipulations may tightly constrict attention resources on the cued location, in turn potentially influencing the functioning of visual cells for enhanced perceptual processing.

Experimental investigation of degassing properties of geothermal fluids

<p>Geothermal energy, the extraction of hot water from the subsurface (500 m to 5 km deep), is generally considered one of the key technologies to achieve the demands of the energy transition.  One of the main problems during production of geothermal waters is degassing. Many subsurface waters contain substantial amounts of dissolved gasses. As the hot water travels up the production well, the pressure and/or temperature drop will cause dissolved gas to come out of the solution. This causes several problems, such as corrosion of the facilities (due to pH changes and/or degassing-related precipitation) and in some cases even to blocking of the reservoir as the free gas limits the water flow.  To better understand under which conditions free gas nucleates, we need confirmation of theoretical bubble point pressure and temperature, and understand what controls the evolution of the bubble front:  i.e. what are the conditions under which free gas emerges from the solution and at what rate are bubbles created?</p><p>An experimental setup was designed in which the degassing process can be observed visually. The setup consists of a high-pressure visual cell which contains water saturated with dissolved gas at high-pressure. The pressure within the cell can be reduced in a reproducible manner using a back-pressure regulator at the outlet of the system. A high-speed camera paired with a uniform LED light source is used to record the degassing process. The pressure in the cell is monitored using a pressure transducer which is synchronized with the camera. The resulting images are then analysed using a MATLAB routine, which allows for determination of the bubble point pressure and rate of bubble formation.</p><p>The first two sets of experiments at ambient temperatures (~20 <sup>o</sup>C) were carried out using two different gases, N<sub>2</sub> and CO<sub>2</sub>. Initial pressure was 70 and 30 bar for the N<sub>2</sub> and CO<sub>2</sub> experiments respectively. In these first experiments we determined the influence of the initial fluid used to pressurize the system. Using gas as the initial fluid causes a large amount of bubbles, whereas only a single bubble was observed for a system where degassed water is used as the initial fluid. An intermediate system where degassed water is pumped into a system full of air at ambient conditions and is subsequently pressurized yields a number of bubbles in between the two systems described previously. All three methods give reproducible bubble point pressures within 2 bar (i.e. pressure where the first free bubble is formed). There are clear differences in bubble point between N<sub>2</sub> and CO<sub>2</sub>.</p><p>A series of follow-up experiments is planned that will investigate specific properties at more extreme conditions: at higher pressures (up to 500 bar) and temperatures (500 <sup>o</sup>C) and using high-salinity brines (2.5 M).</p>

Estimation of the Influence of Associated Petroleum Gas with a High Carbon Dioxide Content on the Oil Displacement Regime in the Development of the Tolumskoye Field

Depending on reservoir conditions, composition of reservoir oil and gas agent, various modes of oil displacement by gas can be implemented in reservoir conditions. The most preferable mode from the standpoint of the completeness of oil recovery is the mode of miscible displacement of oil by gas. The main parameter indicating the achievement of the miscible displacement mode is the minimum miscibility pressure. The most popular and reliable laboratory method for determining the minimum mixing pressure is the slim-tube method. The results of laboratory studies performed to determine the value of the minimum miscibility pressure of reservoir oil from the Tolumskoye field and associated petroleum gas of the Semividovskaya group of fields and also to determine the mode of oil displacement by associated petroleum gas are presented. To determine the parameters of reservoir oil and change its properties at various molar concentrations, the standard PVT research technique was used. To determine the minimum miscibility pressure, the slim-tube technique was used. To assess the mechanism of miscibility process development, chromatographic analysis of the sampled gas composition and visual analysis of the phase fluids behavior by means of a visual cell were additionally performed. Two series of filtration experiments were performed to displace the recombined oil model of the Tolumskoye field by the model of associated petroleum gas from the Semividovskaya group of fields on slim models. According to the obtained dependence of the oil displacement coefficient on pressure, when oil from the Tolumskoye field was displaced by associated petroleum gas of the Semividovskaya group of fields, the minimum miscibility pressure would be 14.8 MPa. Based on the criteria for determining the mixing mode, as a result of generalization and comprehensive analysis of the research results, it was found that for the conditions of the Tolumskoye field, the mode of oil displacement by associated petroleum gas of the Semividovskaya group of fields was the mode of the developed multi-contact miscible displacement (the mechanism of condensation of solvent components into the oil phase).

Visualizing Interactions Between Liquid Propane and Heavy Oil

In this study, we use a custom-designed visual cell to investigate nonequilibrium interactions between liquid propane (C3(l)) and a heavy oil sample (7.2 deg API) at varying experimental conditions. We inject C3(l) into the visual cell containing the heavy oil sample (pressure-buildup process) and allow the injected C3(l) to interact with the oil sample (soaking process). We measure visual-cell pressure and visualize the C3/heavy oil interactions during the pressure-buildup and soaking processes. Nonequilibrium interactions occurring at the interfaces of C3(l)/heavy oil and C3(l)/C3(g) are recorded with respect to time. The results show that the complete mixing of heavy oil with C3(l) occurs in two stages. First, upward extracting flows of oil components from bulk heavy oil phase toward C3(l) phase form a distinguished layer (L1) during the soaking process. The extracted oil components become denser over time and move downward (draining flows) toward the C3(l)/heavy oil interface due to gravity. The gradual color change of L1 from colorless (color of pure C3(l)) to black suggests the mixing of oil components with C3(l). After L1 appears to be uniform, a second layer (L2) is formed above L1 in the bulk C3(l) phase. Extracting and draining flows become active once again, leading to the mixing of oil components from L1 into L2. At final conditions, heavy oil and C3(l) appear to be mixed and form a single uniform phase.

EVICAN—a balanced dataset for algorithm development in cell and nucleus segmentation

Motivation Deep learning use for quantitative image analysis is exponentially increasing. However, training accurate, widely deployable deep learning algorithms requires a plethora of annotated (ground truth) data. Image collections must contain not only thousands of images to provide sufficient example objects (i.e. cells), but also contain an adequate degree of image heterogeneity. Results We present a new dataset, EVICAN—Expert visual cell annotation, comprising partially annotated grayscale images of 30 different cell lines from multiple microscopes, contrast mechanisms and magnifications that is readily usable as training data for computer vision applications. With 4600 images and ∼26 000 segmented cells, our collection offers an unparalleled heterogeneous training dataset for cell biology deep learning application development. Availability and implementation The dataset is freely available (https://edmond.mpdl.mpg.de/imeji/collection/l45s16atmi6Aa4sI?q=). Using a Mask R-CNN implementation, we demonstrate automated segmentation of cells and nuclei from brightfield images with a mean average precision of 61.6 % at a Jaccard Index above 0.5.

Investigation of acid pre-flushing and pH-sensitive microgel injection in fractured carbonate rocks for conformance control purposes

Waterflooding in fractured reservoirs is a challenging task due to the presence of high conductive flow pathways such as fractures. Much of the injected water passes through fractures without sweeping the oil in the low permeable area, which results in an early breakthrough. Implementing deep conformance control techniques can be a remedy for this early water breakthrough. pH-sensitive microgel injection is a conformance control method in which the dependency of microgel viscosity to pH guarantees easy injection of these microgels into formations at low pH environments. Because of the geochemical reactions among rock minerals, microgels, and a pre-flushing acid, the microgel pH increases; therefore, these microgels swell and block high conductive fractures. In this study, a designed visual cell containing rock samples is implemented to observe rock–microgel interactions during a pH-sensitive microgel flooding into a fractured carbonate medium. First, the dependency of fracture aperture changes to the acid pre-flush flow rate is examined. Then, we investigate the effect of pH-sensitive microgel concentration on its resistance to block fractures during post-water flooding by studying the gel failure mechanisms (e.g., adhesive separation, cohesive failure). Finally, the effect of an initial aperture of fracture is examined on microgel washout when water injection is resumed. The results showed that both decreasing the acid flow rate and lowering the initial aperture could increase the rate of aperture changes. Moreover, the microgel solution with a concentration of 1 wt% showed the highest resistance (98.2 psi/ft) against post-water injection. Additionally, this microgel concentration had the highest permeability reduction factor. Meanwhile, the smaller initial aperture of fracture contributed to a higher microgel resistance.

Visual Cell Sorting: A High-throughput, Microscope-based Method to Dissect Cellular Heterogeneity

Microscopy is a powerful tool for characterizing complex cellular phenotypes, but linking these phenotypes to genotype or RNA expression at scale remains challenging. Here, we present Visual Cell Sorting, a method that physically separates hundreds of thousands of live cells based on their visual phenotype. Visual Cell Sorting uses automated imaging and phenotypic analysis to direct selective illumination of Dendra2, a photoconvertible fluorescent protein expressed in live cells; these photoactivated cells are then isolated using fluorescence-activated cell sorting. First, we use Visual Cell Sorting to assess the effect of hundreds of nuclear localization sequence variants in a pooled format, identifying variants that improve nuclear localization and enabling annotation of nuclear localization sequences in thousands of human proteins. Second, we use Visual Cell Sorting to recover cells that retain normal nuclear morphologies after paclitaxel treatment, then derive their single cell transcriptomes to identify multiple pathways associated with paclitaxel resistance in human cancers. Unlike alternative methods, Visual Cell Sorting depends on inexpensive reagents and commercially available hardware. As such, it can be readily deployed to uncover the relationships between visual cellular phenotypes and internal states, including genotypes and gene expression programs.