Determination Of Different Types Research Articles

Risk analysis of Spanish companies

AbstractThis paper aims to investigate the determinants of different types of market risk faced by Spanish firms from 2012 to 2019. Using Fama and French's (Journal of Financial Economics, 1993, 33, 3) three‐factor model, we estimate total risk, diversifiable risk, and systematic or non‐diversifiable risk in the three dimensions proposed by these authors: market risk, size risk, and valuation risk. Risk determinants are derived from a series of economic and financial variables obtained from the information contained in financial statements. This information is summarised using a factor analysis that aims to resolve the correlation issues between the proposed measures. The study demonstrates that the systematic risk factors proposed by Fama and French in their 1993 three‐factor model incorporate dimensions of systematic risk that are relevant to investors and that the set of economic and financial variables proposed can explain these risks. Among these variables, profitability and the market to book ratio have the greatest impact in explaining company risk, while factors such as operating and financial leverage, growth, or company insolvency have a much smaller effect as explanatory factors for risk.

Give citizens a task: An innovative tool to compose policy bundles that reach the climate goal

We analyse the preferences of citizens with respect to climate policies in the transport sector. More specifically, we examine the citizens' preference for mixing different policies, the preferences for and determinants of different types of policy bundles, as well as the CO2 reduction achieved with these bundles. To this end, we developed an innovative evaluation tool, in which respondents could mix 11 different policies at various intensity levels according to their preferences with the (non-binding) goal to reduce CO2 emissions of passenger transport in Austria from currently 13.19 to 4.22 mill. tons/year. Respondents interactively received detailed information on ecological, financial and social effects of their policy selection, and could adjust their choice accordingly. We find that respondents display a widespread aversion against highly restrictive policies, but a preference for broad and well-balanced bundles between pull and push and also between different push policies. With these broad bundles, almost 60% of respondents met the ambitious climate goal. We speculate that this surprisingly high level of ambition may be driven by putting citizens into the role of a task solver (achieve the climate goal) instead of a mere choice maker of policies. Our analysis suggests that car affinity (strongly confounded with urban/non-urban residence), self-concern, political trust, the importance of solidarity and fairness, and (most of all) the climate concern determine the participants’ selection (or rejection) of effective policy bundles. The paper provides relevant insights for policymakers, both regarding participatory decision-making tools and acceptable policy bundles.

Biohybrid adsorbent for the preconcentration of lead and its determination in fruit juices by electrothermal atomic absorption spectrometry.

Fruit juices are one of the most non-alcoholic beverages consumed in the world. Essential elements and other nutrients present in fruit juices play an important role in human well-being. However, fruit juices may also contain potentially toxic elements at trace levels, causing health risks. The objective of this work was to develop an analytical methodology based on the preconcentration of lead using a new biodegradable hybrid material composed of Rhodococcus erythropolis AW3 bacteria and Brassica napus hairy roots. The biodegradable hybrid material was implemented in an online solid phase extraction system for the determination of lead in fruit juices by electrothermal atomic absorption spectrometry. Effects of critical parameters on lead retention were studied. Under optimal experimental conditions, extraction efficiency higher than 99.9% and an enrichment factor of 62.5 were achieved. The dynamic capacity of the biodegradable hybrid material was 36 mg/g, which favored the reuse of the column to at least 8 biosorption-desorption cycles. The limit of detection and quantification for preconcentration of 5 mL of sample were 5.0 and 16.5 ng/L lead, respectively. The relative standard deviation was 4.8% (at 1 µg/L lead and n = 10). The developed method was suitable to be applied for lead determination in different types of fruit juices.

A novel quadruple templates molecularly imprinted polymer electrochemical sensor assisted by second-order calibration methods for detection of Sustanon abuse

Sustanon (SUS) consists of testosterone propionate (TP), testosterone phenylpropionate (TPP), testosterone isocaproate (TIC) and testosterone decanoate (TD) which is generally used as a medication to treat the testosterone deficiency in men. Misuse of SUS to enhance the ability of the athletes can be a very serious risk for their health which is discouraged. Therefore, the main aim of this work was based on developing a novel biosensing system for determination of different types of testosterones in SUS to monitor it. A rotating glassy carbon electrode (GCE) was modified with fullerene C60-multiwalled carbon nanotubes-ionic liquid (C60-MWCNTs-IL) and used as the working electrode for recording second-order hydrodynamic square wave voltammetric (hydrodynamic SWV) data at different step potentials including 0.02, 0.025, 0.03, 0.035, 0.04 and 0.045 V as a sensitive method. Different types of testosterones were extracted and preconcentrated by quadruple templates molecularly imprinted polymers (QTMIPs) and they were determined by C60-MWCNTs-IL/GCE. The testosterones showed severely overlapped peaks at the surface of C60-MWCNTs-IL/GCE which were resolved by three-way calibration based on second-order hydrodynamic SWV data. Therefore, a novel sensor assisted by QTMIPs and second-order calibration methods was developed which had a very good performance for the analysis of synthetic and real matrices in simultaneous determination of TP, TPP, TIC and TD with aim of monitoring the SUS.

Étude de la géométrie ventriculaire gauche chez des hypertendus Noirs Africains

AimTo determine the prevalence and determinants of different types of echocardiographic left ventricular remodeling in African black hypertensive patients. Patients and methodsA transversal descriptive study was conducted from January 1, 2015, to March 31, 2016, in the external explorations department of the Abidjan Heart Institute-Côte d'Ivoire. Transthoracic cardiac echo-graphs were performed in 524 (251 women) hypertensive subjects according to the American Society of Echocardiography convention. ResultsTwenty-nine percent of hypertensive patients had cardiac remodeling (in women and men, respectively, concentric remodeling 14.7 % and 15.7 %; concentric hypertrophy 6 % and 10.3 %; eccentric hypertrophy 7.6 % and 3.7 %). Only systolic and diastolic blood pressure levels were significantly correlated with left ventricular mass indexed to body surface area. ConclusionThis study showed a significant proportion of hypertensives with abnormal left ventricular geometry and confirmed the relationship between blood pressure level and left ventricular geometry change.

Effects of biotic interactions on plant fecundity depend on spatial and functional structure of communities and time since disturbance

Abstract Biotic interactions in plant communities affect individual fitness and community dynamics. Interactions between plants vary in space, over time and with organisational complexity. Yet it is challenging to quantify temporal, spatial and functional determinants of different types of interactions between long‐lived perennial plant species and their effect on lifetime fecundity. We studied how plant–plant, pollinator‐ and seed predator‐mediated interactions affect year‐to‐year variation in three fecundity components (cone production, seed set and seed survival) during post‐fire recovery. Age‐stratified data on the three fecundity components were collected in 19 even‐aged communities comprising 20 serotinous Protea shrub species in the South African Fynbos. We analyse data on these fecundity components with neighbourhood models to infer the sign and strength of interactions throughout post‐disturbance recovery, the neighbour plant traits that shape them and the spatial scale at which interactions take place. For each fecundity component, these models describe how neighbourhood effects change over time and with spatial distance between plants. We then predicted neighbourhood effects on individual fecundity components and cumulative reproductive output at different post‐fire stand ages for each focal plant. Competitive effects on cone production and seed set increased with post‐fire stand age as biomass and floral resources for pollinators build up. In contrast, neighbourhood effects on seed survival were weak throughout post‐disturbance recovery. Plant–plant interactions were shaped by neighbour traits related to resource acquisition, whereas animal‐mediated interactions depended on neighbour traits related to resource availability for pollinators and seed predators. The spatial scale of the interactions increased from plant–plant over predator‐mediated to pollinator‐mediated interactions. The joint effect of these interactions on cumulative reproductive output caused the proportion of focal plants experiencing competition to increase with time since fire. Synthesis. We show that temporal changes in biotic interactions throughout post‐disturbance recovery of perennial plant communities depend on functional traits and can be integrated into neighbourhood effects on lifetime fecundity. Studying the temporal, spatial and functional determinants of neighbourhood effects on lifetime fecundity is important for predicting not only individual plant fitness but also population and community dynamics in changing environments.

A Novel Carbon Paste Electrode Modified with N1-Hydroxy-N1,N2-Diphenylbenzamidine for the Electrochemical Determination of Cadmium(II) in Environmental Samples.

The present study introduces a novel electrode for rapid, highly sensitive, and selective electrochemical sensor for cadmium(II) using 5% N1-hydroxy-N1,N2-diphenylbenzamidine (HDPBA) modified carbon paste electrode (CPE) (HDPBA‒CPE). Surface characterizations and structural analysis of the proposed HDPBA‒CPE were performed using several analytical techniques. The voltammetric measurements of Cd(II) were conducted by cyclic voltammetry (CV) and square wave anodic stripping voltammetry (SWASV). Several experimental conditions such as composition and pH of buffer solutions, HDPBA composition, accumulation potential and time, and other voltammetric conditions were optimized. Cd(II) was preconcentrated on the modified electrode surface for 270 s using Britton Robinson (B-R) buffer (0.1 M, pH 4) at −1.0 V versus Ag/AgCl, followed by electrochemical oxidation of the accumulated Cd(II) in the positive scan of SWASV after a quiet time of 10 s. Under optimized parameters, the proposed method showed a linear range of 0.3–100 nM Cd(II) with a detection limit of 0.032 nM. The fabricated HDPBA-modified carbon paste electrode exhibited excellent sensitivity, selectivity, stability, and reproducibility (with RSD of 3.8%). The developed HDPBA‒CPE was used for the quantification of Cd(II) in tobacco and environmental water samples, and it was found to be applicable for the determination of different types of real samples.

Comparison of PCR Methods for Determination of Different Types of Milk Added to Goat Milk

Amaç: Bu çalışma, keçi sütüne karıştırılmış inek ve koyun sütünün tespiti için multipleks konvansiyonel PCR ve Real Time PCR yöntemlerinden hangisinin daha uygun olduğunun belirlenmesi amavıyla yapılmıştır. Gereç ve Yöntem: Bu amaçla Van ilindeki çiftliklerden keçi, inek ve koyun sütünden birer litre süt temin edilmiştir. Keçi sütüne aynı oranlarda inek sütü ve koyun sütü (%1, %2, %5, %0.1 ve %0.5) ilave edilerek PCR deneyleri yapılmıştır. Bu denemelerde mültipleks konvansiyonel ve Real Time PCR kullanıldı. Bulgular: İnek ve koyun sütü denemelerinde keçi sütüne ilave edilen %1, %2 ve %5 inek ve koyun sütünün varlığının multipleks konvansiyonel PCR yöntemi ile belirlenebileceği ortaya konmuştur. Ancak %0.5 oranında eklenen süt karışımlarının jel görüntüsünün pozitifliğinin belirsiz olduğu ve %0.1 oranındaki karışımların tespit edilemediği görülmüştür. Real Time PCR yönteminde ise tüm karışımlarda inek ve koyun sütü varlığı tespit edildi ve pozitif grafikler belirlendi. Sonuç: Bu sonuçlar, Real Time PCR yönteminin, ticari olarak satılan keçi sütü ile %0,1 inek veya koyun sütü karıştırıldığında bile daha güvenilir sonuçlar verdiğini gösterdi.

Patterns and driving forces of the agricultural water footprint of Chinese cities

The patterns and determinants of different types of agricultural water footprints in China are poorly understood at the prefecture-city level. In this paper, we evaluate Chinese agricultural water footprints from 2000 to 2017 and analyzed their spatio-temporal characteristics. Our estimation results show that the annual average agricultural water footprint in China was 5.038 × 109 m3, and the proportions of green water, blue water, and gray water were 70%, 9%, and 21%, respectively. In addition, high agricultural water-footprint cities with obvious urban agglomeration effects are mainly located in the Northeast, the Huanghuai River, the Yangtze River Basin, and Northwestern of Xinjiang, while low agricultural water-footprint cities are concentrated in high coastal urbanization-level areas or less developed agricultural areas of the west. We also investigate their determinants using a spatio-temporal fixed-effect model and find that GDP per capita, total investment in fixed assets, the income level of rural residents, the proportion of food grown, spray and drip irrigation technology, low-pressure pipe irrigation technology and seepage control irrigation technology have significant positive impacts on the agricultural water footprint. In contrast, the proportion of secondary and tertiary industries, social retail consumption, urbanization, technology expenditure, and the effective irrigation area proportion have a significant inhibitory effect. The primary determinants of the agricultural water footprint also vary substantially across water footprint categories (green, blue, and gray water footprints) and regions. Our findings imply that the agricultural water footprint should be incorporated into city water resource management and monitoring system.

How to Reduce Individuals’ Ecological Footprint without Harming Their Well-Being: An Application to Belgium

Human activities are a key driver of many environmental problems the world is facing today, including climate change, the disruption of biogeochemical cycles, and biodiversity loss. Behavioural changes at the individual and household level are needed to reduce humanity’s environmental impact, but people also need the capacity to behave in a sustainable way. If their well-being is negatively impacted or if behaving sustainably is too time consuming or too expensive, people might be less inclined to change their behaviour. In this article, we look at the determinants of different types of pro-environmental behaviour and how these are associated with their experienced levels of well-being. More specifically, we focus on the determinants of behaviours that influence both the ecological footprint (EF) and satisfaction with life. In our analysis we include socio-demographic characteristics and a number of psychological antecedents of pro-environmental behaviour (PEB). The data we use was collected in Flanders (Belgium) and allows us to calculate the EF of each respondent individually. Our main conclusions are threefold. First, even if individuals are provided with opportunities to behave in a more sustainable way, they do not always do so (e.g., richer people on average have a higher EF). Efforts could be put in place at the collective side (e.g., public infrastructure) to stimulate people to reduce their environmental impact. Second, as we distinguish seven EF components, we are able to show differential effects of each of the determinants. Third, the association between PEB and satisfaction with life is not strong: only the type of housing is significantly associated with satisfaction with life. Related to that, the psychological antecedents of PEB are only associated with the EF, not with satisfaction with life.

Income inequality and violent crime: evidence from Indian states

The objective of this study is to examine the determinants of different types of violent crime in India. A panel data model was estimated using data from 28 Indian states and one union territory during the years 1993, 2004 and 2011, covering three decades. Based on the Hausman test result, random effect model was used for all types of violent crime except robbery. Our main result suggests that income inequality measured using Gini coefficient negatively affects the incidence of murder, attempt to commit murder, and kidnapping and abduction. Furthermore, there are evidences suggesting that unemployment is an insignificant variable in explaining the incidence of different categories of violent crime. Consistent with previous research, lower levels of violent crimes are associated with a higher literacy rate. The current study also discusses the possible reasons for the above mentioned relationship between economic variables and violent crime.

Optimization and Validation of a Headspace Solid-Phase Microextraction with Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometric Detection for Quantification of Trace Aroma Compounds in Chinese Liquor (Baijiu).

The detection of trace aroma compounds in samples with complex matrices such as Chinese liquor (Baijiu) requires a combination of several methods, which makes the analysis process very complicated. Therefore, a headspace solid-phase microextraction (HS-SPME) method coupled with two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS) was developed for the quantitation of a large number of trace compounds in Baijiu. Optimization of extraction conditions via a series of experiments revealed that dilution of the alcohol content of 8 mL of Baijiu to 5%, followed by the addition of 3.0 g of NaCl and subsequent SPME extraction with DVB/CAR/PDMS fiber coating over 45 min at 45 °C was the most suitable. To check the matrix effects, various model Baijiu matrices were investigated in detail. The quantitative method was established through an optimized model synthetic solution, which can identify 119 aroma compounds (esters, alcohols, fatty acids, aldehydes and ketones, furans, pyrazines, sulfur compounds, phenols, terpenes, and lactones) in the Baijiu sample. The developed procedure provided high recovery (86.79–117.94%), good repeatability (relative standard deviation < 9.93%), high linearity (R2 > 0.99), and lower detection limits than reported methods. The method was successfully applied to study the composition of volatile compounds in different types of Baijiu. This research indicated that the optimized HS-SPME–GC×GC-TOFMS method was a valid and accurate procedure for the simultaneous determination of different types of trace compounds in Baijiu. This developed method will allow an improved analysis of other samples with complex matrices.

Anemia in Sports: A Narrative Review.

Recent years have brought about new understandings regarding the pathogenesis of anemia in sports. From hemodilution and redistribution considered to contribute to the so-called “sports anemia” to iron deficiency caused by increased demands, dietary restrictions, decreased absorption, increased losses, hemolysis, and sequestration, to genetic determinants of different types of anemia (some related to sport), the anemia in athletes deserves a careful and multifactorial approach. Dietary factors that reduce iron absorption (e.g., phytate, polyphenols) and that augment iron’s bioavailability (e.g., ascorbic acid) should be considered. Celiac disease, more prevalent in female athletes, may underlie an unexplained iron deficiency anemia. Iron loss during exercise occurs in several ways: sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis. From a practical point of view, assessing iron status, especially in the athletes at risk for iron deficiency (females, adolescents, in sports with dietary restrictions, etc.), may improve the iron balance and possibly the performance. Hemoglobin and serum ferritin are measures that are easily employable for the evaluation of patients’ iron status. Cutoff values should probably be further assessed with respect to the sex, age, and type of sport. A healthy gut microbiome influences the iron status. Athletes at risk of iron deficiency should perform non-weight-bearing, low-intensity sports to avoid inducing hemolysis.

The determinants of different types of private-sphere pro-environmental behaviour: an integrating framework

The determinants of different types of private-sphere pro-environmental behaviour: an integrating framework

Determination of different types of fixed effects in three-dimensional panels*

In this paper, we propose a jackknife method to determine the type of fixed effects in three-dimensional panel data models. We show that with probability approaching 1, the method can select the correct type of fixed effects in the presence of only weak serial or cross-sectional dependence among the error terms. In the presence of strong serial correlation, we propose a modified jackknife method and justify its selection consistency. Monte Carlo simulations demonstrate the excellent finite sample performance of our method. Applications to two datasets in macroeconomics and international trade reveal the usefulness of our method.

Determinants of Performance in Paced and Maximal 800-m Running Time Trials.

We aimed to identify the underpinning physiological and speed/mechanical determinants of different types of 800-m running time trials (i.e., with a positive or negative pacing strategy) and key components within each 800-m time trial (i.e., first and final 200 m). Twenty trained male 800-m runners (800-m personal best time (min:s): 1:55.10 ± 0:04.44) completed a maximal 800-m time trial (800MAX) and one pacing trial, whereby runners were paced for the first lap, and speed was reduced by 7.5% (800PACE) relative to 800MAX, whereas the last lap was completed in the fastest time possible. Anaerobic speed reserve, running economy, the velocity corresponding with V˙O2peak (VV˙O2peak), maximal sprint speed (MAXSS), maximal accumulated oxygen deficit, and sprint force-velocity-power profiles were derived from laboratory and field testing. Carnosine content was quantified by proton magnetic resonance spectroscopy in the gastrocnemius and soleus and expressed as a carnosine aggregate Z (CAZ) score to estimate muscle typology. Data were analyzed using multiple stepwise regression analysis. MAXSS and vV˙O2peak largely explained the variation in 800MAX time (r2 = 0.570; P = 0.020), whereas MAXSS was the best explanatory variable for the first 200-m time in 800MAX (adjusted r2 = 0.661, P < 0.001). Runners with a higher CAZ score (i.e., higher estimated percentage of type II fibers) reduced their last lap time to a greater extent in 800PACE relative to 800MAX (adjusted r2 = 0.413, P < 0.001), whereas better maintenance of mechanical effectiveness during sprinting, a higher CAZ score and vV˙O2peak was associated with a faster final 200-m time during 800PACE (adjusted r2 = 0.761, P = 0.001). These findings highlight that diversity in the physiological and speed/mechanical characteristics of male middle-distance runners may be associated with their suitability for different 800-m racing strategies to have the best chance of winning.

Civic Competence in the Logic of Openness: A Phenomenological Approach

The article offers a phenomenological view on civic competency, openness of education, and values as type of competencies. The need for such a comparison is dictated by the discrepancy between the humanistic meanings of education and the social reality in which they are supposed to be implemented. It is assumed that a phenomenological perspective can present civic competency as a borderline connecting both the areas. This study is methodically supported by explication of the philosophical (transcendental-phenomenological) logic of the concept of openness.The appeal to openness, which is the essence of human subjectivity (autonomy), clarifies the substantive character of civic competency structure.Firstly, the study underlines the connection between openness and universalism as cultural principle (that is, in culture and through culture) of self-determination of the mind, constituting civic mindedness as a universal moral and legal modus of subjectivity. Bringing the civic idea to the competency range is the own task of education, which can be accomplished only in continuous actualization of the concept of openness.Secondly, the article proposes to consider the concept of value in the meaning of “type of competencies” according to the Council of Europe’s “Reference Framework of Competence for Democratic Culture” as a tool for crystallizing the self-determining mind into civic competency. Attention to this document is drawn by the coherence of openness and universalism with educational policies and practices, which is formalized in the pedagogical design of values as a type of competence. The study’s argumentation confirms this connection and ascertains that an open edu­cational system is defined in its essence not by a set of accessible educational environment technologies, but by the depth of its rooting in the logic of openness.Thirdly, the actualization of values as a type of competence in the logic of openness provides an opportunity for phenomenological designing of pedagogical technologies. The essential idea of this approach is that civic competency can be constituted as a semantic determination of different types of subject knowledge and, through their correction, can transform broad social contexts. As an example of that sort of transformative participation, the article presents the values’ influence on the strengthening of human capital in aggregation of new technologies and inequality.

Development of multi-residue extraction procedures using QuEChERS and liquid chromatography tandem mass spectrometry for the determination of different types of organic pollutants in mussel.

This study aimed to develop multi-residue methods for the extraction of organic pollutants in mussels (Mytilus galloprovincialis), including 11 pharmaceuticals, 5 pesticides, 5 perfluoroalkyl substances (PFASs) and 2 illicit drugs. The combination of 4 different QuEChERS methods and 12 clean-ups (a total of 44 combinations) was tested. QuEChERS included acidified (AQ), non-acidified (SQ) and their miniaturized versions. The clean-ups included 6 different conventional dispersive solid phase extraction (dSPE) plus 2 enhanced matrix removal (EMR-Lipid) and 4 SPE procedures (including sorbents focused on phospholipid removal and polymer-based). After sample analysis via HPLC-MS/MS, the three methods that provided the best results were validated in terms of linearity, accuracy, precision, sensitivity and matrix effect. The methods selected were the combination of (i) SQ and EMR-Lipid, (ii) AQ and Z-sep+ bulk-based dSPE and (iii) AQ and graphitized carbon black (GCB)-based dSPE. Recoveries at two concentration levels (50 and 500ng/g) ranged 54-124%, 59-124% and 60-127%, respectively, and limits of quantification (LOQs) were < 30ng/g for most analytes using any of the methods. The three methods were tested in non-spiked mussel samples purchased in local markets, but organic pollutants were not detected in any sample. However, the methods probed to successfully extract a wide range of organic pollutants families in mussel samples from the market and from bioaccumulation trials.

Alpha-defensins determination in different types of synovial fluid and parallel collected serum samples by ELISA

The study aims were to verify the serum (S) and synovial fluid (SF) reference intervals (RIs) for human neutrophil defensins (HNP1-3); measure S and SF defensin concentrations in different types of SF, including non-inflammatory, inflammatory non-pyogenic, inflammatory pyogenic, and hemorrhagic; and to compare the HNP1-3 concentrations in SF and S with those of other inflammatory biomarkers. SF and S samples were collected from 92 patients. HNP1-3 concentrations were determined using enzyme-linked immunosorbent assays; glucose, lactate, interleukin-6, and procalcitonin using an automatic analyzer; and presepsin using a Pathfast system. There were 61 non-inflammatory, 11 inflammatory non-pyogenic, 11 inflammatory pyogenic, and 9 hemorrhagic SF. Non-inflammatory SF was divided into non-inflammatory normal and non-inflammatory osteoarthritis. The former was used to estimate the HNP1-3 RI in SF and S. The estimated HNP1-3 RIs of SF and S were 12.47-437.42 mg/L and 5.45-44.75 µg/L, respectively. HNP1-3 differed significantly between S and SF and individual groups of SF (P<0.001 and P=0.001, respectively). There were significant relationships between SF HNP1-3 and S HNP1-3 (P<0.001), S C-reactive protein (P<0.001), and S interleukin-6 (P=0.007), and between SF HNP1-3 and SF C-reactive protein (P=0.004) and SF interleukin-6 (P<0.001). The highest kappa coefficient was between SF HNP1-3 and SF interleukin-6 (κ=0.507). We validated the SF HNP1-3 diagnostic kit and demonstrated that SF and S HNP1-3 are promising biomarkers for distinguishing inflammatory from non-inflammatory joint diseases.

Effect of Grain Shape on Quasi‐Static Fluid‐Fluid Displacement in Porous Media

AbstractWe study how grain shapes impact multiphase flow in porous media in the quasi‐static regime using an extended pore‐network model. The algorithm allows the explicit determination of different types of pore‐scale instabilities and tracks the interface motion during the fluid‐fluid displacement process. It also includes the volume capacitance model, such that both the evolution of capillary pressure signal and sizes of Haines jumps can be captured. Further, it considers the pinning of menisci at sharp edges of grains, through which the distribution of effective contact angles can be obtained. Simulations are carried out across a wide range of wetting conditions for different particle shapes. Our results show that the effective contact angle distribution during displacement widens as the grain becomes more angular, which consequently modifies the macroscopic fluid invasion morphology. By analyzing various characteristic metrics during displacement, including capillary pressure signal, Haines jump size distribution, and fractal dimension, our results highlight the profound influence of particle shape on the multiphase flow.