Individual Partitions Research Articles

An epidemic model for COVID-19 transmission in Argentina: Exploration of the alternating quarantine and massive testing strategies

The COVID-19 pandemic has challenged authorities at different levels of government administration around the globe. When faced with diseases of this severity, it is useful for the authorities to have prediction tools to estimate in advance the impact on the health system as well as the human, material, and economic resources that will be necessary. In this paper, we construct an extended Susceptible–Exposed–Infected–Recovered model that incorporates the social structure of Mar del Plata, the 4°most inhabited city in Argentina and head of the Municipality of General Pueyrredón. Moreover, we consider detailed partitions of infected individuals according to the illness severity, as well as data of local health resources, to bring predictions closer to the local reality. Tuning the corresponding epidemic parameters for COVID-19, we study an alternating quarantine strategy: a part of the population can circulate without restrictions at any time, while the rest is equally divided into two groups and goes on successive periods of normal activity and lockdown, each one with a duration of τ days. We also implement a random testing strategy with a threshold over the population. We found that τ=7 is a good choice for the quarantine strategy since it reduces the infected population and, conveniently, it suits a weekly schedule. Focusing on the health system, projecting from the situation as of September 30, we foresee a difficulty to avoid saturation of the available ICU, given the extremely low levels of mobility that would be required. In the worst case, our model estimates that four thousand deaths would occur, of which 30% could be avoided with proper medical attention. Nonetheless, we found that aggressive testing would allow an increase in the percentage of people that can circulate without restrictions, and the medical facilities to deal with the additional critical patients would be relatively low.

Full-scale CFD simulation of commercial pig building and comparison with porous media approximation of animal occupied zone

Many CFD simulation studies substitute Animal Occupied Zone (AOZ) as porous media to reduce computation time and resources. With the improved computational capacity, it is now possible to include realistic geometric models of individual animals and partition walls. This study presents a CFD model of a large commercial-sized, hybrid ventilated pig building with 1,360 animals. It compares the developed full-scale model (that includes pigs and partition walls) with a simplified model that substitutes AOZ with a porous media approximation. We find that the simplified model with porous media approximation predicts the airflow rates and overall flow characteristics in the building as good as the full-scale model. Full-scale simulations with animals and partition walls give a snapshot of a particular situation in the building and the environmental conditions in the AOZ level; for example, we found that even in a well-ventilated pig building temperatures in the AOZ were, on average, 3 °C - 5 °C higher than at a height 0.5 m above the AOZ. Including the realistic shape of animals and the partition walls is overkill if the aim is to study ventilation configurations’ effects. However, porous media models are not good enough to describe the conditions in the AOZ.

I am not talking to you: Partitioning an audience in an attempt to solve the self-promotion dilemma

This work investigates self-promotion partitioning, a strategy used in group conversations by self-promoters trying to overcome the self-promotion dilemma – a desire to share self-enhancing information without appearing to be overtly bragging. Self-promotion partitioning occurs when individuals partition their audience by addressing one or more specific recipients, deliberately turning unaddressed recipients into “bystanders.” Across a series of experiments and the analysis of secondary data, we show people disproportionally favor partitioning their audience when they face the self-promotion dilemma, both in face-to-face conversations and on social media platforms. They do so because they expect bystanders to believe they were not intended recipients, and in turn be less likely to see the self-promoter as overtly bragging, resulting in a more favorable impression. We also identify an important boundary condition, audience size; when partitioning creates a single bystander, the self-promoter worries partitioning would make the lone bystander feel excluded and ultimately hurt impressions.

Bioguided Fractionation of Local Plants against Matrix Metalloproteinase9 and Its Cytotoxicity against Breast Cancer Cell Models: In Silico and In Vitro Study (Part II).

In our previous work, the partitions (1 mg/mL) of Ageratum conyzoides (AC) aerial parts and Ixora coccinea (IC) leaves showed inhibitions of 94% and 96%, respectively, whereas their fractions showed IC50 43 and 116 µg/mL, respectively, toward Matrix Metalloproteinase9 (MMP9), an enzyme that catalyzes a proteolysis of extracellular matrix. In this present study, we performed IC50 determinations for AC n-hexane, IC n-hexane, and IC ethylacetate partitions, followed by the cytotoxicity study of individual partitions against MDA-MB-231, 4T1, T47D, MCF7, and Vero cell lines. Successive fractionations from AC n-hexane and IC ethylacetate partitions led to the isolation of two compounds, oxytetracycline (OTC) and dioctyl phthalate (DOP). The result showed that AC n-hexane, IC n-hexane, and IC ethylacetate partitions inhibit MMP9 with their respective IC50 as follows: 246.1 µg/mL, 5.66 µg/mL, and 2.75 × 10−2 µg/mL. Toward MDA-MB-231, 4T1, T47D, and MCF7, AC n-hexane demonstrated IC50 2.05, 265, 109.70, and 2.11 µg/mL, respectively, whereas IC ethylacetate showed IC50 1.92, 57.5, 371.5, and 2.01 µg/mL, respectively. The inhibitions toward MMP9 by OTC were indicated by its IC50 18.69 µM, whereas DOP was inactive. A molecular docking study suggested that OTC prefers to bind to PEX9 rather than its catalytic domain. Against 4T1, OTC showed inhibition with IC50 414.20 µM. In conclusion, this study furtherly supports the previous finding that AC and IC are two herbals with potential to be developed as triple-negative anti-breast cancer agents.

Dietary Fiber Source and Length of Feeding Partitions Differentially Affected Behavior, Immune Status, and Productivity of Group-Housed Dry Sows

Aggression is one of the major welfare concerns among group-housed sows, especially during feeding and regrouping. There are no simple solutions, but any attempt to reduce aggression should be considered. Therefore, the aim was to reduce aggression among group-housed gestating sows by feeding sows different dietary fiber using individual feeding places made from either short- or long-length partitions. Five blocks (n = 36 sows/block) of primiparous and multiparous sows were fed a dietary treatment of either 30% wheat middlings and 15% soybean hulls (MIDD-SY) or 30% distillers dried grains and 30% corn germ meal (DDGS-GM) and housed in pens (9 sows/pen) with individual feeding partitions that were either shoulder (short) or full-body (long) in length. Sow behavior, skin lesions, immune status, and performance were measured. Sow behavior, including aggression and lesion severity scores, were mainly affected by partition length. Aggressive encounters were greater and remained elevated among sows in pens with short partitions until 9 weeks post-grouping but were reduced among sows in pens with long partitions by 3 weeks. During feeding, sows in pens with short ones were more likely to be displaced than were those in pens with long ones. Percentages of time spent lying, standing, eating, and oral–nasal–facial behaviors were also differentially influenced by partition length. Dietary fiber differentially influenced immune status and productivity. For example, sows fed MIDD-SY had higher lymphocyte proliferation and increased neutrophils, while those fed DDGS-GM had deeper backfat and weaned heavier piglets. Overall, the length of the feeding partitions influenced the aggressive encounters, other behaviors, and lesion scores; in turn, the fibrous source differentially influenced several immune measures and sow productivity.

Finding bugs in database systems via query partitioning

Logic bugs in Database Management Systems (DBMSs) are bugs that cause an incorrect result for a given query, for example, by omitting a row that should be fetched. These bugs are critical, since they are likely to go unnoticed by users. We propose Query Partitioning, a general and effective approach for finding logic bugs in DBMSs. The core idea of Query Partitioning is to, starting from a given original query, derive multiple, more complex queries (called partitioning queries), each of which computes a partition of the result. The individual partitions are then composed to compute a result set that must be equivalent to the original query's result set. A bug in the DBMS is detected when these result sets differ. Our intuition is that due to the increased complexity, the partitioning queries are more likely to stress the DBMS and trigger a logic bug than the original query. As a concrete instance of a partitioning strategy, we propose Ternary Logic Partitioning (TLP), which is based on the observation that a boolean predicate p can either evaluate to TRUE, FALSE, or NULL. Accordingly, a query can be decomposed into three partitioning queries, each of which computes its result on rows or intermediate results for which p, NOT p, and p IS NULL hold. This technique is versatile, and can be used to test WHERE, GROUP BY, as well as HAVING clauses, aggregate functions, and DISTINCT queries. As part of an extensive testing campaign, we found 175 bugs in widely-used DBMSs such as MySQL, TiDB, SQLite, and CockroachDB, 125 of which have been fixed. Notably, 77 of these were logic bugs, while the remaining were error and crash bugs. We expect that the effectiveness and wide applicability of Query Partitioning will lead to its broad adoption in practice, and the formulation of additional partitioning strategies.

The Influence of Environmental Features on the Morphometric Variation in Mauritia flexuosa L.f. Fruits and Seeds.

The environmental heterogeneity may reflect the different morphological and phenotypic traits of individuals belonging to a single species. We used 14 morphological traits of Mauritia flexuosa L.f. to understanding the relation between environment and phenotypic traits. Twenty-five fruits were collected from each of the 10 individuals sampled in each study site: Chapada dos Guimarães (CG), Vila Bela da Santíssima Trindade (VB), and Alta Floresta (AF). We analyzed the genetic divergence, using the standardized Euclidean distance, the sequential method of Tocher, unweighted pair group method with arithmetic mean (UPGMA), and the projection of the distances onto 2D plane, and calculated the relative importance of the traits evaluated. The analysis showed the partition of individuals into three main groups: Two groups comprising the majority of individuals. Fresh fruit weight, pulp rate, fresh pulp weight, and moisture rate were the traits that most helped explaining the difference between materials. The results shown in the current study evidenced the influence of these three different environments on the biometric traits of M. flexuosa. Such influence has led to the formation of Alta Floresta and Vila Bela da Santíssima Trindade individuals in different groups, whereas the Chapada dos Guimarães individuals were able to permeate the two other groups, although they showed stronger tendency to group with individuals from Vila Bela da Santíssima Trindade.

Colorist: An r package for colouring wildlife distributions in space–time

Abstract Maps are essential tools for communicating information about wildlife distributions in space and time. As observational datasets grow and enable description of distributions at broader spatiotemporal extents and finer spatiotemporal resolutions, new opportunities arise for visualizing when and where animals occur. Here we present a package for the r statistical computing environment, colorist, that facilitates visualization of animal distributions in space and time using raster inputs. In addition to enabling display of sequential change in distributions through the use of small multiples, colorist provides functions for extracting several features of interest from a sequence of distributions and for visualizing those features within an HCL (hue–chroma–luminance) colour space. Resulting maps allow for ‘fair’ visual comparison of occurrence, abundance or probability density values across space and time and can be used to address questions about where, when and how consistently a species or individual is likely to be found. Functions can also be harnessed to visualize distributions of multiple species or individuals within a single time period when research questions are focused on understanding the degree to which species or individuals partition space. By colouring temporal features of distributions, while simultaneously controlling their perceptual weight, we expand the set of tools available for exploring wildlife movements through space–time and for communicating research results. We expect colorist functions will prove useful for visualizing other types of multivariate data that we have yet to consider.

Compositional neural scene representations for shading inference

We present a technique for adaptively partitioning neural scene representations. Our method disentangles lighting, material, and geometric information yielding a scene representation that preserves the orthogonality of these components, improves interpretability of the model, and allows compositing new scenes by mixing components of existing ones. The proposed adaptive partitioning respects the uneven entropy of individual components and permits compressing the scene representation to lower its memory footprint and potentially reduce the evaluation cost of the model. Furthermore, the partitioned representation enables an in-depth analysis of existing image generators. We compare the flow of information through individual partitions, and by contrasting it to the impact of additional inputs (G-buffer), we are able to identify the roots of undesired visual artifacts, and propose one possible solution to remedy the poor performance. We also demonstrate the benefits of complementing traditional forward renderers by neural representations and synthesis, e.g. to infer expensive shading effects, and show how these could improve production rendering in the future if developed further.

An Efficient Processing Approach for Colored Point Cloud-Based High-Throughput Seedling Phenotyping

Plant height and leaf area are important morphological properties of leafy vegetable seedlings, and they can be particularly useful for plant growth and health research. The traditional measurement scheme is time-consuming and not suitable for continuously monitoring plant growth and health. Individual vegetable seedling quick segmentation is the prerequisite for high-throughput seedling phenotype data extraction at individual seedling level. This paper proposes an efficient learning- and model-free 3D point cloud data processing pipeline to measure the plant height and leaf area of every single seedling in a plug tray. The 3D point clouds are obtained by a low-cost red–green–blue (RGB)-Depth (RGB-D) camera. Firstly, noise reduction is performed on the original point clouds through the processing of useable-area filter, depth cut-off filter, and neighbor count filter. Secondly, the surface feature histograms-based approach is used to automatically remove the complicated natural background. Then, the Voxel Cloud Connectivity Segmentation (VCCS) and Locally Convex Connected Patches (LCCP) algorithms are employed for individual vegetable seedling partition. Finally, the height and projected leaf area of respective seedlings are calculated based on segmented point clouds and validation is carried out. Critically, we also demonstrate the robustness of our method for different growth conditions and species. The experimental results show that the proposed method could be used to quickly calculate the morphological parameters of each seedling and it is practical to use this approach for high-throughput seedling phenotyping.

Competitive equilibria in Shapley–Scarf markets with couples

We investigate the existence and properties of competitive equilibrium in Shapley–Scarf markets involving an exogenous partition of individuals into couples. The presence of couples generates preference interdependencies which cause existence problems. For both cases of transferable and non-transferable income among partners, we establish properties for preferences that are sufficient for the existence of an equilibrium. Moreover, we show that these properties define a maximal preference domain.

A Partition Dirichlet Process Model for Functional Data Analysis

Recently, extensions of the Dirichlet process to the functional domain have been presented in the literature. These processes can be classified based on the type of labeling they induce across different arguments in the domain, i.e., marginal or joint labeling. We show that marginal labeling processes have undesirable properties if functional observations are assumed to be almost surely continuous. Joint labeling processes avoid this undesirable behavior. They are specified through finite dimensional distributions for locations across the entire domain. They range from a common label for all arguments (relatively easy to fit) to joint local label selection at every argument (computationally very demanding). Here, we offer a middle ground - a joint labeling process which partitions the domain of the stochastic process and assign labels to individual partition elements. We call the proposed model a partition functional Dirichlet process and show that it can outperform both of the foregoing extremes of joint labeling. Given data that is a sample from each function in a collection of independent functions over the given domain, we employ this process as a prior for the true functions. We show results from simulation studies as well as a dataset arising from reflectance curves to demonstrate the performance of this process and make comparison with the two extreme labeling models.

Self-partitioning SlipChip for slip-induced droplet formation and human papillomavirus viral load quantification with digital LAMP

Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide, and persistent HPV infection can cause warts and even cancer. Nucleic acid analysis of HPV viral DNA can be very informative for the diagnosis and monitoring of HPV. Digital nucleic acid analysis, such as digital PCR and digital isothermal amplification, can provide sensitive detection and precise quantification of target nucleic acids, and its utility has been demonstrated in many biological research and medical diagnostic applications. A variety of methods have been developed for the generation of a large number of individual reaction partitions, a key requirement for digital nucleic acid analysis. However, an easily assembled and operated device for robust droplet formation without preprocessing devices, auxiliary instrumentation or control systems is still highly desired. In this paper, we present a self-partitioning SlipChip (sp-SlipChip) microfluidic device for the slip-induced generation of droplets to perform digital loop-mediated isothermal amplification (LAMP) for the detection and quantification of HPV DNA. In contrast to traditional SlipChip methods, which require the precise alignment of microfeatures, this sp-SlipChip utilized a design of “chain-of-pearls” continuous microfluidic channel that is independent of the overlapping of microfeatures on different plates to establish the fluidic path for reagent loading. Initiated by a simple slipping step, the aqueous solution can robustly self-partition into individual droplets by capillary pressure-driven flow. This advantage makes the sp-SlipChip very appealing for the point-of-care quantitative analysis of viral load. As a proof of concept, we performed digital LAMP on a sp-SlipChip to quantify human papillomaviruses (HPVs) 16 and 18 and tested this method with fifteen anonymous clinical samples.

Droplet and Microchamber-Based Digital Loop-Mediated Isothermal Amplification (dLAMP).

Digital loop-mediated isothermal amplification (dLAMP) refers to compartmentalizing nucleic acids and LAMP reagents into a large number of individual partitions, such as microchambers and droplets. This compartmentalization enables dLAMP to be an excellent platform to quantify the absolute number of the target nucleic acids. Owing to its low requirement for instrumentation complexity, high specificity, and strong tolerance to inhibitors in the nucleic acid samples, dLAMP has been recognized as a simple and accurate technique to quantify pathogenic nucleic acid. Herein, the general process of dLAMP techniques is summarized, the current dLAMP techniques are categorized, and a comprehensive discussion on different types of dLAMP techniques is presented. Also, the challenges of the current dLAMP are illustrated together with the possible strategies to address these challenges. In the end, the future directions of the dLAMP developments, including multitarget detection, multisample detection, and processing nucleic acid extraction are outlined. With recently significant advances in dLAMP, this technology has the potential to see more widespread use beyond the laboratory in the future.

Reassessing the role of morphology in bryophyte phylogenetics: Combined data improves phylogenetic inference despite character conflict

Morphological data has gained renewed attention and has been shown to be crucial in clarifying the phylogenetic relationship in a wide range of taxa. In the last decades, phylogenetic analyses of sequence-level data have radically modified the systematic schemes within bryophytes (early non-vascular land plants) and have revealed a widespread pattern of conflict with morphology-based classifications. Yet, a comprehensive evaluation of character conflict has not yet been performed in the context of combined matrices. In this study, we evaluate the impact of morphology on bryophyte phylogeny following a total-evidence approach across 10 published matrices. The analysed matrices span a wide range of bryophytes, taxonomic levels, gene sampling and number of morphological characters and taxa. Data conflict was addressed by measuring: (i) the topological congruence between individual partitions, (ii) changes in support values of the combined data relative to the molecular partition and (iii) clade stability. The association between these measures and the number of morphological characters per taxon (Nc/T ratio) and the proportion of non-fixed characters (i.e., inapplicable, polymorphic and missing data) was explored. In the individual partition analyses, the Nc/T ratio correlated positively with the topological congruence in six to seven datasets depending on the weighting scheme. The proportion of non-fixed cells had a minor influence on congruence between data partitions. The number of characters and proportion of non-fixed data varied significantly between morphological datasets that improved congruence between data types. This variation suggests that morphological datasets affect the results of combined analyses in different ways, depending on the taxa studied. Combined analyses revealed that, despite the low congruence values between partitions, integrating data types improves support values and stability. However, while non-fixed data had no negative effect on support values, stability was reduced as the proportion of non-fixed cells increased. Nc/T ratio was negatively associated with support values and it showed ambiguous responses in stability evaluations. Overall, the results indicate that adding morphology may contribute to the inference of phylogenetic relationships of bryophytes despite character conflict. Our findings suggest that merely comparing (a) morphology-based classifications with molecular phylogenies or (b) the outcome from individual data partitions can misestimate data conflict. These findings imply that analyses of combined data may provide conservative assessments of data conflict and, eventually, lead to an improved sampling of morphological characters in large-scale analyses of bryophytes.

Temporal stability of functional brain modules associated with human intelligence.

Individual differences in general cognitive ability (i.e., intelligence) have been linked to individual variations in the modular organization of functional brain networks. However, these analyses have been limited to static (time‐averaged) connectivity, and have not yet addressed whether dynamic changes in the configuration of brain networks relate to general intelligence. Here, we used multiband functional MRI resting‐state data (N = 281) and estimated subject‐specific time‐varying functional connectivity networks. Modularity optimization was applied to determine individual time‐variant module partitions and to assess fluctuations in modularity across time. We show that higher intelligence, indexed by an established composite measure, the Wechsler Abbreviated Scale of Intelligence (WASI), is associated with higher temporal stability (lower temporal variability) of brain network modularity. Post‐hoc analyses reveal that subjects with higher intelligence scores engage in fewer periods of extremely high modularity — which are characterized by greater disconnection of task‐positive from task‐negative networks. Further, we show that brain regions of the dorsal attention network contribute most to the observed effect. In sum, our study suggests that investigating the temporal dynamics of functional brain network topology contributes to our understanding of the neural bases of general cognitive abilities.

Ecological biomass allocation strategies in plant species with different life forms in a cold desert, China

Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass (AGB) and below-ground biomass (BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass (TB), leaf mass ratio (LMR) and root/shoot ratio (R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms (ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants (1.675) than in ephemeral (0.154) and annual (0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants.

ROOTCLUS: Searching for "ROOT CLUSters" in Three-Way Proximity Data.

In the context of three-way proximity data, an INDCLUS-type model is presented to address the issue of subject heterogeneity regarding the perception of object pairwise similarity. A model, termed ROOTCLUS, is presented that allows for the detection of a subset of objects whose similarities are described in terms of non-overlapping clusters (ROOT CLUSters) common across all subjects. For the other objects, Individual partitions, which are subject specific, are allowed where clusters are linked one-to-one to the Root clusters. A sound ALS-type algorithm to fit the model to data is presented. The novel method is evaluated in an extensive simulation study and illustrated with empirical data sets.

Surfactant as selective modulator in the partitioning of dyes in aqueous two-phase systems: A strategy for separation

In this work, aqueous two-phase systems (ATPSs) were employed to separate two model dyes, remazol golden yellow (RY) and methylene blue (MB), using the cetyltrimethylammonium bromide (CTAB) surfactant as a selective modulator in the partitioning. Experiments involving individual and simultaneous partitioning of the dyes were performed in the absence and presence of CTAB in ATPSs formed by a polymer (polyethylene glycol (PEG), polypropylene glycol (PPG), or poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) copolymer (L35)), a salt ((NH4)2SO4, MgSO4, Na2SO4, or Li2SO4), and water. In experiments of individual partitioning, RY and MB were transferred to the top phase in ATPSs formed using PEG in the absence of CTAB. However, in the presence of certain surfactant concentrations, the MB dye remained in the top phase, while the RY dye was transferred to the bottom phase. The same result was obtained in experiments of simultaneous partitioning. This was attributed to a specific interaction between CTAB and RY, which promoted the formation of RY-CTAB aggregates that were stabilized in the bottom phase. The amount of RY transferred to the bottom phase in the presence of CTAB was highly dependent on the polymer molar mass and the natures of the salt and the polymer. Interestingly, the surfactant did not promote the transfer of RY to the bottom phase in ATPSs formed by PPG or L35, due to competition between the polymer and the RY dye for the CTAB monomers. The best separation factor between the dyes was of 271.2 in the ATPS formed by PEG with molar mass of 1500 g mol−1, MgSO4, and water, hence demonstrating the potential of ATPSs for separation among dyes.

Numerical investigations of key aspects influencing CO2 foam performance in fractured carbonate system using CO2 soluble surfactants

Experimental studies have showed that CO2 soluble surfactants were more effective than aqueous soluble surfactant as supercritical CO2 foaming agent in fractured carbonate cores, in terms of higher foam strengths and oil recoveries. This paper aims to reveal the potential causes responsible to those superiorities and probe the impacts of key aspects during this complex process. Variable surfactants are examined to investigate the presence of optimal partition coefficient. The impact of surfactant structure on critical foaming concentration is also studied. Effect of reservoir pressure is investigated through stepwise independent manipulations attempting to decouple its influences on miscibility between CO2/oil, free gas phase availability and surfactant partition coefficient between CO2/brine. Effect of injection foam quality (gas volumetric fraction) is probed at constant liquid injection rate. It is found that the optimal partition coefficient for selected system is affected by multiple practical conditions including injection periods and surfactant structure relevant model parameters, but not determined by absolute coefficient values. The results of increasing system pressure and injection foam quality are combination of multiple aspects, including miscibility between CO2/Oil, local pressure drop, foam apparent viscosity, among of CO2 injection, gaseous CO2 available for surfactant delivery, and interplay between faster surfactant propagation and reduced local pressure gradient (“spreading” effect). The contribution of promoted or suppressed spreading effect could depend on magnitude of individual partition coefficient. The findings here reveal the complex interactions of multiple key aspects affecting CO2 soluble surfactant foams performance and promote the understandings to apply this novel technology in fractured systems.