Miracle-dz/UniFAR-FTUs huggingface dataset:
Formation of liquid bridges between porous matrix blocks

It is widely accepted that, in fluid flow and transport in fractured porous media, there exists some degree of block-to-block interaction that may lead to capillary continuity. The formation of liquid bridges causing interaction between blocks will affect oil recovery from naturally fractured reservoirs. However, the accurate modeling of the growth and detachment of liquid bridges that may cause capillary continuity between matrix blocks remains a controversial topic. In an attempt to improve our understanding of the problem, a mechanistic model is developed in this work for the formation of liquid bridges between porous blocks. The proposed model considers growth and detachment of pendant liquid droplets perpendicular to the horizontal and smooth fracture between porous matrix blocks. The liquid bridge model is then coupled with various upscaled fracture capillary pressure models to study the liquid bridge formation process. An expression is obtained that relates the commonly used fracture capillary pressure to the critical length of the liquid element. Results based on various fracture capillary pressure models reveal that the threshold Bond number is an important parameter in the formation of liquid bridges. We introduce a simple mechanistic model for the formation of liquid bridges in a horizontal fracture between two porous blocks, advancing our understanding of the two-phase flow in fractured porous media. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Clickstream Knowledge Tracing: Modeling How Students Answer Interactive Online Questions

Knowledge tracing (KT) is a research topic which seeks to model the knowledge acquisition process of students by analyzing their past performance in answering questions, based on which their performance in answering future questions is predicted. However, existing KT models only consider whether a student answers a question correctly when the answer is submitted but not the in-question activities. We argue that the interaction involved in the in-question activities can at least partially reveal the thinking process of the student, and hopefully even the competence of acquiring or understanding each piece of the knowledge required for the question. Based on real student interaction clickstream data collected from an online learning platform on which students solve mathematics problems, we conduct clustering analysis for each question to show that clickstreams can reflect different student behaviors. We then propose the first clickstream-based KT model, dubbed clickstream knowledge tracing (CKT), which augments a basic KT model by modeling the clickstream activities of students when answering questions. We apply different variants of CKT and compare them with the baseline KT model which does not use clickstream data. Despite the limited number of questions with clickstream data and its noisy nature which may compromise the data quality, we show that incorporating clickstream data leads to performance improvement. Through this pilot study, we hope to open a new direction in KT research to analyze finer-grained interaction data of students on online learning platforms.
Subversive Learning Analytics

This paper puts forth the idea of a subversive stance on learning analytics as a theoretically-grounded means of engaging with issues of power and equity in education and the ways in which they interact with the usage of data on learning processes. The concept draws on efforts from fields such as socio-technical systems and critical race studies that have a long history of examining the role of data in issues of race, gender and class. To illustrate the value that such a stance offers the field of learning analytics, we provide examples of how taking a subversive perspective can help us to identify tacit assumptions-in-practice, ask generative questions about our design processes and consider new modes of creation to produce tools that operate differently in the world.
Neuroimaging studies exploring the neural basis of social isolation

Abstract According to the social brain hypothesis, the human brain includes a network designed for the processing of social information. This network includes several brain regions that elaborate social cues, interactions and contexts, i.e. prefrontal paracingulate and parietal cortices, amygdala, temporal lobes and the posterior superior temporal sulcus. While current literature suggests the importance of this network from both a psychological and evolutionary perspective, little is known about its neurobiological bases. Specifically, only a paucity of studies explored the neural underpinnings of constructs that are ascribed to the social brain network functioning, i.e. objective social isolation and perceived loneliness. As such, this review aimed to overview neuroimaging studies that investigated social isolation in healthy subjects. Social isolation correlated with both structural and functional alterations within the social brain network and in other regions that seem to support mentalising and social processes (i.e. hippocampus, insula, ventral striatum and cerebellum). However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies with longitudinal designs are needed to measure the effect of social isolation in experimental v. control groups and to explore its relationship with perceived loneliness, ultimately helping to clarify the neural correlates of the social brain.
RADIOCARBON DATES FROM THE MONASTERY ON KOM H IN OLD DONGOLA (SUDAN) AND THE CHRONOLOGY OF MEDIEVAL NUBIAN POTTERY

ABSTRACT The paper presents and discusses a series of radiocarbon (14C) dates from a medieval Nubian monastery found on Kom H of Old Dongola, the capital of the kingdom of Makuria located in modern-day Sudan. The monastery was founded in the 6th–7th century AD and although it probably ceased to function in the 14th century, the site remained occupied until the beginning of the 15th century. The investigated courtyard of the monastery was in use from the 11th to the 14th century, as indicated by the ceramics and 14C analysis results presented here. The dates under consideration are the first published series of 14C dates from this site, which is of crucial importance for historical research on medieval Nubian Christianity and monasticism. They permit to begin building an absolute chronological framework for research on the archaeological finds from the site and region. A group of finds in particular need of such a framework are ceramics, and the implications of the 14C dates for pottery assemblages found in the dated contexts are discussed. The conclusions summarize the significance of the datings for the history of the site.
Factors Impacting Reproductive Success and Asset Value of Beef Breeding Females in Mississippi Auctions

Abstract A breeding female’s perceived value is a complicated process and depends on a combination of expected production costs, reproductive success, and calf values. A conceptual asset value model based on female characteristics as signals and net implicit marginal value expectations is developed. A hedonic model based on sequentially sold individuals at multiple Mississippi auction locations is estimated by panel regression. Among other findings, pregnant females are discounted in proportion to abortion risk, which decreases toward birth. A follow-up cost/benefit analysis indicates producers are better off from at home pregnancy checking and selling only nonpregnant females or cow/calf pairs.
Geometric phase methods with Stokes theorem for a general viscous swimmer

Abstract The geometric phase techniques for swimming in viscous flows express the net displacement of a swimmer as a path integral of a field in configuration space. This representation can be transformed into an area integral for simple swimmers using the Stokes theorem. Since this transformation applies for any loop, the integrand of this area integral can be used to help design these swimmers. However, the extension of this Stokes theorem technique to more complicated swimmers is hampered by problems with variables that do not commute and by how to visualise and understand the higher-dimensional spaces. In this paper, we develop a treatment for each of these problems, thereby allowing the displacement of general swimmers in any environment to be designed and understood similarly to simple swimmers. The net displacement arising from non-commuting variables is tackled by embedding the integral into a higher-dimensional space, which can then be visualised through a suitability constructed surface. These methods are developed for general swimmers and demonstrated on three benchmark examples: Purcell's two-hinged swimmer, an axisymmetric squirmer in free space and an axisymmetric squirmer approaching a free interface. We show in particular that, for swimmers with more than two modes of deformation, there exists an infinite set of strokes that generate each net displacement. Hence, in the absence of additional restrictions, general microscopic swimmers do not have a single stroke that maximises their displacement.
Viscous fingering of miscible annular ring

Abstract Miscible viscous fingering (VF) of the annulus of a more viscous fluid radially displaced by a less viscous fluid is investigated through both numerical computations and experimental study. We aim to understand how VF with finiteness in a radial displacement different from the classical radial VF and the instability of a slice displaced rectilinearly with a uniform velocity. It is observed that the VF of a miscible annular ring is a persistent phenomenon in contrast to the transient nature of VF of a miscible slice. Although new fingers cease to appear after some time but due to the radial spreading of the area available for VF, a finite number of fingers always remain at a later time when diffusion is the ultimate dominating force. A statistical analysis is performed for the numerical data and it is found that the second moment of the averaged profile, variance, is a non-monotonic function of time, contrary to variance in classical radial VF and rectilinear VF with one fluid sandwiched between layers of another. The minimum in the variance indicates the interaction of two fronts which is visible in terms of pressure fingers, but not the concentration fingers indicating a faster growth of pressure than the concentration growth. In addition, for existence of critical parameters for instability in terms of viscosity contrast and amount of sample, the variation of the finger length with flow rate is found to be dependent on the amount of the more viscous fluid confined in the annulus.
RADIOCARBON DATING OF A LATE ANTIQUE NECROPOLIS FROM FELANITX (MALLORCA, BALEARIC ISLANDS)

ABSTRACT The excavation of a building in the village of Felanitx in the eastern part of the island of Mallorca (Balearic Islands) has revealed the existence of a small necropolis. The inhumations did not provide grave goods except for a bronze belt buckle for which the typological study suggests a Late Antique chronology. The stratigraphical sequence however seems to suggest a possible evolution of the space across time since some graves are cut by others. In order to obtain an absolute date for the necropolis and to verify if there are chronological differences between the graves, a total of 6 human bones samples have been 14C dated by AMS. The results of the radiocarbon dating confirm a Late Antique chronology (4th to 7th century AD) for the graves but do not suggest a chronological evolution. Despite the fact that the knowledge of the necropolis is still fragmentary, the results are extremely important because they provide an absolute date for a Late Antique necropolis in the Mallorcan rural area.
TREE-RING-RADIOCARBON DATING AT A LATE CONTACT PERIOD KITKAHAHKI PAWNEE SITE ON THE CENTRAL GREAT PLAINS, USA

ABSTRACT This study obtained calendar dates by radiocarbon accelerator mass spectrometry (14C AMS) dating sequential tree-rings of wooden support posts from the buried remains of traditional Kitkahahki Pawnee earthlodges preserved at an archaeological site on the Central Great Plains, USA. The tree-ring segments from the site were dendrochronologically analyzed prior to this study, but the cross-matched site chronology could not be definitively cross-dated and was thus “floating” in time. Our study represents the first floating tree-ring chronology from the Great Plains to be anchored in time by means of independent radiocarbon analysis. Three specimens were analyzed and dated to 1724–1774 CE (82.0% probability), 1774–1794 CE (95.4% probability), and 1800–1820 CE (95.4% probability). These dates correspond to the hypothetical timing of Kitkahahki ethnogensis, the main phase of village growth in the area, and a later reoccupation during a turbulent period in regional history. The results of this study conform to a scenario in which chaotic social conditions correspond to an increase in residential mobility between the core of Pawnee territory and a southern frontier in the Republican River valley.
Mechanics of Arboreal Locomotion in Swinhoe’s Striped Squirrels: A Potential Model for Early Euarchontoglires

Differences between arboreal and terrestrial supports likely pose less contrasting functional demands on the locomotor system at a small body size. For arboreal mammals of small body size, asymmetrical gaits have been demonstrated to be advantageous to increase dynamic stability. Many of the extant arboreal squirrel-related rodents display a small body size, claws on all digits, and limited prehensility, a combination that was proposed to have characterized the earliest Euarchontoglires. Thus, motion analysis of such a modern analog could shed light onto the early locomotor evolution of eurarchontoglirans. In this study, we investigated how Swinhoe’s striped squirrels (Tamiops swinhoei; Scuiromorpha) adjust their locomotion when faced with different orientations on broad supports and simulated small branches. We simultaneously recorded high-Hz videos (501 trials) and support reaction forces (451 trials) of squirrels running on two types of instrumented trackways installed at either a 45° incline (we recorded locomotion on inclines and declines) or with a horizontal orientation. The striped squirrels almost exclusively used asymmetrical gaits with a preference for full bounds. Locomotion on simulated branches did not differ substantially from locomotion on the flat trackway. We interpreted several of the quantified adjustments on declines and inclines (in comparison to horizontal supports) as mechanisms to increase stability (e.g., by minimizing toppling moments) and as adjustments to the differential loading of fore- and hind limbs on inclined supports. Our data, in addition to published comparative data and similarities to the locomotion of other small arboreal rodents, tree shrews, and primates as well as a likely small body size at the crown-group node of Euarchontoglires, render a preference for asymmetrical gaits in early members of the clade plausible. This contributes to our understanding of the ancestral lifestyle of this mammalian ‘superclade’.
Characteristics of bifacial solar cells under bifacial illumination with various intensity levels

The characteristics of bifacial solar cells with different rear structures were investigated under front, rear and bifacial illumination with an intensity of 0.4–4.2 suns. Five kinds of solar cells, rear flat local‐BSF cells, rear textured local‐BSF cells (textured RLB cells), rear total‐BSF cells, rear floating‐emitter cells, and triode cells with double‐sided junctions, were tested. The I–V characteristics of the cells under bifacial illumination were measured with a newly designed measurement system that simultaneously illuminated both surfaces of the cells. In the short‐circuit current (JSC) and the saturation current evaluations, the bifacial illumination effect, which means that the power output of the cell is intrinsically improved by adding rear illumination, was not observed. Although the RLB cells showed a nonlinear increase in JSC and enhanced VOC, these increases did not make a practical contribution to extra output because of the low levels of these characteristics. When we evaluated the maximum output power, the bifacial illumination effect was only observed in the triode cell. A triode cell can decrease resistive loss by introducing light from both surfaces, compared with a conventional cell with one junction. Copyright © 2001 John Wiley & Sons, Ltd.
Art Teachers' Attitudes Toward Online Learning: An Empirical Study Using Self Determination Theory

The pandemic in 2020 made online learning the widely used modality of teaching in several countries and it has also entered the spotlight of educational research. However, online learning has always been a challenge for disciplines (engineering, biology, and art) that require hands-on practice. For art teaching or training, online learning has many advantages and disadvantages. How art teachers embrace and adapt their teaching for online delivery remains an unanswered question. This research examines 892 art teachers' attitudes toward online learning, using learning environment, need satisfaction, mental engagement, and behavior as predictors. Structural equation modeling was used to explore the relationship between these four dimensions during these teachers' participation in an online learning program. The results reveal significant correlations between the learning environment, need satisfaction, mental engagement, and behavior. Moreover, this study reveals the group characteristics of art teachers, which can actually be supported by online learning programs. These findings provide insights into how art teachers view and use online learning, and thus can shed lights on their professional development.
Use of Social Media, Network Avenues, Blog and Scientific Information Systems Through the Website Promoting the Mediterranean Diet as a Method of a Health Safeguarding

The Mediterranean Diet (MD) is considered by the Food and Agriculture Organization of the United Nations (FAO) as “the best for people and the most sustainable for the environment”. In the era of Big Data, new tools are emerging to facilitate health care research. One form of Big Data is the one that accumulates in the traffic caused by publications on the web and social networks. These data can provide valuable information about the epidemiological patterns of certain behavior and interest of the population. The objective of this study was to explore through websites and its associated official social media on information related to different publications of both international or national nutrition official agencies as well as publications of scientific diffusion for the design of future nutritional education and MD programs. This study opens up future avenues of research, such as studying the acceptance of post writing in other languages in those northern European countries where MD is being implemented. Or through the use of subtitled videos, due to the great acceptance of this format. The MD remains in 2020 considered the best option to follow a healthy diet without difficulties, therefore it is very important to continue promoting the need for good nutritional health based on its qualities.
Seasonal Efficiency of Supplemental LED Lighting on Growth and Photomorphogenesis of Sweet Basil

For decisions on supplemental lighting a quantitative knowledge of the plants' responses to light under varying conditions is fundamental. In this study, we developed light dose-response curves of growth and morphological traits for Ocimum basilicum L. and examined the effects of light color (blue, red, and white plus far-red) and natural environment (season) on these curves. Four greenhouse experiments were conducted throughout the year to determine the efficiencies of the light regimes on growth and their effects on plant morphology. A special aspect was the photosynthetic efficiency of far-red light. Linear and monomolecular relationships were found for the relationships between plant traits and supplemental light dose. Traits related to biomass productivity increased linearly with light dose whereas some morphological characters showed a saturation behavior. Red light and white plus far-red light were more efficient in plant dry weight production than blue light, and the plants adapted differently to the light qualities: higher biomass under red light was related to a plant architecture more favorable for light capture, i.e., taller plants and bigger leaves. White plus far-red light, on the other hand, increased leaf mass per area (LMA) and light use efficiency (LUE). Blue light resulted in lowest plant light interception and LUE. Considering photosynthetic effects of near-infrared light (PPFD800, 400–800 nm) instead of photosynthetic photon flux density (PPFD700, 400–700 nm) led to strongly reduced efficiencies. Traits related to photosynthesis such as dry weight, LMA and LUE were particularly affected by PPFD800. There were no interactions between the efficiencies of the different light colors and the seasons. Efficiencies of all light regimes were significantly lower during summer compared to spring and winter. Higher dry weight production during summer compared to winter and spring were a consequence of increased light interception rather than changes in LUE. The observed differences in seasonal efficiencies were directly linked to the amount of natural light present as indicated by changes in the ratio of supplemental to natural light.
ORAI1 Ca2+ Channel as a Therapeutic Target in Pathological Vascular Remodelling

In the adult, vascular smooth muscle cells (VSMC) are normally physiologically quiescent, arranged circumferentially in one or more layers within blood vessel walls. Remodelling of native VSMC to a proliferative state for vascular development, adaptation or repair is driven by platelet-derived growth factor (PDGF). A key effector downstream of PDGF receptors is store-operated calcium entry (SOCE) mediated through the plasma membrane calcium ion channel, ORAI1, which is activated by the endoplasmic reticulum (ER) calcium store sensor, stromal interaction molecule-1 (STIM1). This SOCE was shown to play fundamental roles in the pathological remodelling of VSMC. Exciting transgenic lineage-tracing studies have revealed that the contribution of the phenotypically-modulated VSMC in atherosclerotic plaque formation is more significant than previously appreciated, and growing evidence supports the relevance of ORAI1 signalling in this pathologic remodelling. ORAI1 has also emerged as an attractive potential therapeutic target as it is accessible to extracellular compound inhibition. This is further supported by the progression of several ORAI1 inhibitors into clinical trials. Here we discuss the current knowledge of ORAI1-mediated signalling in pathologic vascular remodelling, particularly in the settings of atherosclerotic cardiovascular diseases (CVDs) and neointimal hyperplasia, and the recent developments in our understanding of the mechanisms by which ORAI1 coordinates VSMC phenotypic remodelling, through the activation of key transcription factor, nuclear factor of activated T-cell (NFAT). In addition, we discuss advances in therapeutic strategies aimed at the ORAI1 target.