Past Studies Research Articles

Race, Racism, and Ethnicity

This article examines the debates over historiographical uses of the terms race, racism, and ethnicity in the study of the premodern past. It begins with an analysis of conventional approaches to defining race, which understand the concept to be fundamentally modern and reject uses of the term in the study of the premodern world. Such conventional approaches to historicizing race are predicated on problematically essentialist definitions of the term that preclude comparisons of varying types of racisms that manifest across different historical periods. The article spotlights some of the arguments in favor of formulations of race and racism that allow for comparative analyses of premodern instances of racism, relying on the ideas of scholars working in race theory, philosophy of race, and premodern critical race studies. It also puts forward a working model of racism useful for analyzing examples of race-thinking found in Christian texts of the late antique period, focusing specifically on negative significations of blackness. Broadly, the article aims to outline more dynamic and fruitful approaches to conceptualizing race, racism, and ethnicity in the study of the ancient world.

Linking formulation feedstock to printability by robocasting: a case study of eco-friendly alumina pastes

Robocasting stands as a pertinent additive manufacturing technique for producing intricate ceramic parts. Amidst stricter environmental regulations, the adoption of natural additives becomes imperative. This study investigates the influence of plant-based additives on the rheology and printability of eco-friendly pastes.Various 50 vol%-alumina pastes were formulated using natural binders, plasticizers and dispersants (e.g., lignosulfonate, polysaccharides, glycerol) and then assessed through oscillation and flow rheological analyses. Paste viscosity and rigidity often deviated from printability maps reported in the literature, showing the complexity of defining universal printability criteria. A comprehensive investigation was conducted on the water retention capabilities of additives, liquid phase migration and paste drying kinetics.This paper highlights the critical importance of constraining liquid phase migration within eco-friendly ceramic pastes and the crucial role of polymer chain reorientation under shear. Consequently, this research lays diversifying formulations, offering sustainable solutions for industrial ceramic applications.

The Evolution of Entrepreneurship: A Comparative Study of Perspectives Past, Present, and Future

Entrepreneurship has become an important element in the economic and social development of a country. This research aims to analyze the development of entrepreneurship from the past to the present, as well as predict how entrepreneurship will develop in the future. Social, economic, and cultural factors that influence society's views on entrepreneurship will be explored to gain a comprehensive understanding. Through comparative analysis, it is hoped that changes and continuity in entrepreneurship throughout history can be revealed, as well as the opportunities and challenges that will be faced in the future era. The data and information in this research were collected from various sources, including academic literature, industry publications, and statistical reports. It is hoped that the findings of this research will provide valuable insights for academics, practitioners, and policymakers in the field of entrepreneurship

Stability Analysis and Robust Parameter Design of DC-Voltage Loop for Three-Phase Grid-Connected PV Inverter Under Weak Grid Condition

In the grid-connected inverter, both the PLL (phase-locked loop) and DVL (DC-voltage loop) can lead to the frequency coupling in the weak grid. Instabilities caused by PLL frequency coupling have been widely discussed. For DVL, past studies have analyzed the effect of DVL parameters on the degree of frequency coupling, but it is quite unclear how DVL parameters affect the inverter stability and how DVL can be designed under the weak grid. Hence, by fully considering the abovementioned frequency coupling, an accurate admittance model of PV (photovoltaic) grid-connected inverter is established in this study. By deriving the modified admittance matrix, the effects of grid impedance and DVL parameters on the frequency coupling are clearly studied. In addition, by modeling the equivalent inverter output impedance, the impact of DVL on the inverter stability under the weak grid is revealed. As proved, the increase of DVL bandwidth <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vbw</sub> and grid impedance will aggravate the frequency coupling, but the current distortion does not necessarily increase. Meanwhile, the increase of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vbw</sub> helps to improve the inverter stability under the weak grid. Accordingly, a novel design for DVL in the weak grid is proposed. Experiments verify the correctness of the analysis and design.

Fly ash-GGBS blended geopolymer mortar for early engineering characteristic at ambient temperature

Geopolymer concept is by using industrial waste materials which is rich in silica and alumina, then activating them with alkaline solution. An appropriate binder combination that achieves high early age strength at ambient temperature using FA is still subject required. Thus, this study has been designed in two stages which involving the paste and mortar studies. The alkaline activator as a blend of sodium hydroxide and sodium silicate solution with SS/SH ratio of 2.5, NaOH molarity of 12 M and L/B ratio of 0.43 are used for geopolymer composite. Compressive strength, water absorption and shrinkage are tested on geopolymer mortar with various level of blended combination. High volume content (60–80 %) gave a promising early age compressive strength at ambient temperature. Metakaolin gave a further strength improvement on geopolymer mortar. Overall, the finding suggested that the geopolymer with high FA content is suitable for cement-based material repair product.

A systematic review on the formative assessment practice in teaching and learning in secondary school

Formative assessment is an assessment that is conducted throughout the teaching and learning process. Therefore, teachers should play an important role in mastering the appropriate approaches to practicing formative assessment. According to previous studies, some teachers are unable to comprehend the roles of formative assessment practices in teaching and learning, which prevents them from using them effectively in the classroom. Many researchers have conducted research related to the practice of formative assessment in schools due to this issue. Therefore, this article aims to conduct a systematic literature review (SLR) on past studies related to the practice of formative assessment in teaching and learning in secondary schools. This SLR writing process has been referred to as the Preferred Reporting Items for systematic review and meta-analysis (PRISMA) writing standard. To find related articles and resources in this systematic literature review, two main databases, namely Web of Science and Scopus, were used. A total of 19 articles were extracted from 366 from 2017 to 2021, with exceptions and inclusion criteria considered. Based on the theme analysis, this SLR has three main themes: assessment diversity; assessment strategies, and student learning development. Thus, this study suggests that all compulsory levels of education understand formative assessment conceptually and its implementation comprehensively. This can be disseminated through teacher professional development training programs. It is hoped that such programs will develop teachers who are committed to integrating the concept and practice of assessment for the benefit of students in twenty-first century education.

Do you cite what you tweet? Investigating the relationship between tweeting and citing research articles

Abstract The last decade of altmetrics research has demonstrated that altmetrics have a low to moderate correlation with citations, depending on the platform and the discipline, among other factors. Most past studies used academic works as their unit of analysis to determine whether the attention they received on Twitter was a good predictor of academic engagement. Our work revisits the relationship between tweets and citations where the tweet itself is the unit of analysis, and the question is to determine if, at the individual level, the act of tweeting an academic work can shed light on the likelihood of the act of citing that same work. We model this relationship by considering the research activity of the tweeter and its relationship to the tweeted work. The results show that tweeters are more likely to cite works affiliated with their same institution, works published in journals in which they also have published, and works in which they hold authorship. It finds that the older the academic age of a tweeter the less likely they are to cite what they tweet, though there is a positive relationship between citations and the number of works they have published and references they have accumulated over time.

Sport, migration and diaspora: the case of Ivorian track and field athletes

PurposeThis study focused on Ivorian track and field athletes who were current or former members of the Ivorian national team to understand athletes’ experiences with migration, diaspora and sport.Design/methodology/approachParticipatory action research (PAR) methodology was used in this research study (Lenette and Nesvaderani, 2021). According to Schinke and Blodgett (2016), PAR is a type of qualitative research used to engage the researcher and researched. The researcher and researched work together to understand the issues of a situation and communicate a plan to work toward resolving those issues (Kemmis et al., 2014). Using PAR helped to engage multiple people in the study, and as more research studies explore forced migration and sport, more scholars are starting to lean on the methodology to create a more diverse perspective and to include marginalized populations in the world of scholarly research (Stone, 2018; Robinson et al., 2019).FindingsKey findings illustrate Ivorian athletes’ ability to forge a bond that transcended tribal and political differences through geographical proximity and sport opportunity, allowing them to (re)connect with their Ivorian diaspora by representing the national team.Originality/valueThis research paper expands on past studies in sport and migration by showcasing the fluid nature of how diaspora constructs an athlete’s national identity once they are forced to leave their homeland.

Marine lebensspuren: improving the classification of seafloor traces from underwater imagery and observations

Taxonomy is a dynamic and evolving scientific field in biological and paleontological research, which describes and systematises species and other taxa and thus lays the foundation to solve and structure biological questions. The study of past (fossil) and modern (present) seafloor traces holds huge potential for understanding the composition, behavioural ecology, and ecosystem impact of benthic communities, e.g., in terms of bioturbation and carbon cycling. In trace fossil research (paleoichnology), ichnotaxonomical analysis is based on the application of ichnotaxobases, morphology being the most important and useful criterion. However, marine neoichnological analyses (modern traces; lebensspuren) have no standardised ichnotaxobases. In the literature, classification based on morphological descriptions or behavioural assignations can be found, but without consensus. This lack of standardised terminology hinders comparisons among studies and regions. Through this manuscript, we discuss the limitations of marine lebensspuren characterisation through underwater observations and how further classification could be done (i.e., possible ichnotaxobases). Considering that most of the classifications will be based on marine still images, we propose a classification for marine lebensspuren based on a combination of three labels: 1) morphology (e.g., M-ridged trail), 2) behaviour determination (e.g., locomotion and feeding), and 3) tracemaker taxonomy (e.g., Echinocrepis rostrata). Accordingly, the classification will be 1) M-ridged trail 2) Locomotion and feeding 3) Echinocrepsis rostrata. A set of recommendations is given to address all three labels. Also, we describe some of the contrasting positions of paleo- and neoichnology, particularly where a solution presently seems difficult to find, and argue that open nomenclature could be useful as still images contain large amounts of information. Finally, we provide examples of the usage of this classification for input to a marine lebensspuren online repository and how this nomenclature can help to compare worldwide lebensspuren in a consistent way.

DNA metabarcoding reveals ecological patterns and driving mechanisms of archaeal, bacterial, and eukaryotic communities in sediments of the Sansha Yongle Blue Hole

The Sansha Yongle Blue Hole (SYBH) is the world’s deepest marine blue hole with unique physicochemical characteristics. However, our knowledge of the biodiversity and community structure in SYBH sediments remains limited, as past studies have mostly focused on microbial communities in the water column. Here, we collected sediment samples from the aerobic zone (3.1 to 38.6 m) and the deep anaerobic zone (150 m, 300 m) of the SYBH and extracted DNA to characterize the archaeal, bacterial, and eukaryotic communities inhabiting these sediments. Our results showed that the archaeal and bacterial communities were dominated by Thaumarchaeota and Proteobacteria, respectively. The dominant taxa of eukaryotes in different sites varied greatly, mainly including Phaeophyceae, Annelida, Diatomea and Arthropoda. All three examined domains showed clear vertical distributions and significant differences in community composition between the aerobic and anaerobic zones. Sulfide played a prominent role in structuring the three domains, followed by salinity, nitrous oxide, pH, temperature and dissolved oxygen, all of which were positively correlated with the turnover component, the main contributor to beta diversity. Neutral community model revealed that stochastic processes contributed to more than half of the community variations across the three domains. Co-occurrence network showed an equal number of positive and negative interactions in the archaeal network, while positive interactions accounted for ~ 80% in the bacterial and eukaryotic networks. Our findings reveal the ecological features of prokaryotes and eukaryotes in SYBH sediments and shed new light on community dynamics and survival strategies in the special environment of marine blue holes.

Loanwords in Basic Vocabulary as an Indicator of Borrowing Profiles

Abstract Loanwords carry information on linguistic interactions, and can also reveal (pre-)historical population contacts. The contact history of a particular language family is an essential component of historical linguistics, but it is also illuminating for integrative studies of the human past. However, data availability and the time-consuming nature of etymology mean that comprehensive research on loanword layers exists for relatively few languages, forcing us to rely on limited material for others. This paper compares the loanword layers in the basic and total vocabulary of six well-studied Uralic languages, assessing how accurately the borrowing profile in basic vocabulary reflects the full profile of a language. We define “borrowing profile” as the known contact history of a language reflected by its loanword layers. We demonstrate that the loanword layers in basic vocabulary provide an adequate cross-section of the full borrowing profile, although basic vocabulary manifests prehistoric contacts more strongly than more recent contacts.

On-Surface Fabrication toward Polar 2D Macromolecular Crystals.

Polar 2D macromolecular structures have attracted significant attention because of their ferroelectricity and ferro-magnetism. However, it is challenging to synthesize them experimentally because dipoles or spins of these macromolecules tend to cancel each other. So far, there has been no successful strategy for assembling macromolecules in a unidirectional manner, achieving stereoregular polymerization on metal surfaces, and creating polar 2D polymer crystals. Recent progress in molecular assembly, on-surface polymer synthesis, and direct control of molecules using electric field applications provides an opportunity to develop such strategies. In this regard, we first review past studies on chiral and achiral molecular assembly, on-surface polymer synthesis, and orientation control of polar molecules. Then, we discuss our newly developed approach called "vectorial on-surface synthesis", which is based on "dynamic chirality" of compass precursors, stereoselective polymerization, and favorable interchain interactions originating from CH-π interactions. Finally, we conclude with a prospective outlook.

Локальні студії радянського повсякдення: досвід, уроки, виклики

The purpose of the article is an attempt to analyze the results of the activities of domestic researchers of the history of Soviet everyday life (historians, ethnologists, cultural scientists, anthropologists, sociologists, art critics), which were presented at seven all-Ukrainian scientific and theoretical seminars of the series «Everyday Life: Visions and Meanings», held at Vinnytsia State Pedagogical University M. Kotsyubynskyi during 2015-2023. The research methodology is based on a combination of general scientific, special-historical and interdisciplinary methods and tools of socio-cultural analysis. The scientific novelty of the work lies in the fact that it attempts a primary (self) analysis and generalization of the local experience of the problematization of the Soviet past through the lens of everyday life. Conclusion. The initiative of the scientists of the Center for the Study of Everyday History of the Faculty of Vinnytsia Pedagogical University was launched in the context of the beginning of Russian aggression as a response to the request for an in-depth historical-anthropological and socio-cultural study of the (un)completed Soviet past through the visions and meanings of the life world of an ordinary Soviet person. Researchers of leading scientific institutions and higher educational institutions of Ukraine actively responded to the proposal of a scientific and theoretical dialogue between specialists. Some summaries of the journey can be expressed in several theses. First, the choice of topics for each subsequent seminar was not arbitrary. It is determined, on the one hand, by specific public requests and the professional readiness of researchers, and on the other hand, it arose from the specific interdisciplinary work of each previous seminar. Secondly, in Ukraine as  result, a stable core of qualified researchers of the Soviet past from various scientific fields has formed, to which new generations of researchers are interested. Systematic scientific dialogues contributed to the expansion of the subject field of Soviet everyday life, deepened and improved the methodology of its study, significantly for the development of an adequate understanding and interpretation of the Soviet past.

High-frequency suppression of inductive coupling between flux qubit and transmission line resonator

Abstract We perform theoretical calculations to investigate the naturally occurring high-frequency cutoff in a circuit comprising a flux qubit coupled inductively to a transmission line resonator (TLR). Specifically, a decoupling occurs between the qubit and the high-frequency modes. The coupling strength between the qubit and resonator modes increases with mode frequency ω as ω at low frequencies and decreases as 1 / ω at high frequencies. This result is similar to those of past studies that considered somewhat similar circuit designs. By avoiding the approximation of ignoring the qubit-TLR coupling in certain steps in the analysis, we obtain effects not captured in previous studies. In particular, we obtain a resonance effect that shifts the TLR mode frequencies close to qubit oscillation frequencies. We derive expressions for the TLR mode frequencies, qubit-TLR coupling strengths and qubit Lamb shift. We identify features in the spectrum of the system that can be used in future experiments to test and validate the theoretical model.

Feasibility of RPG for Learning about Empathy, Creativity, and Self-efficacy

Feasibility of RPG for Learning about Empathy, Creativity, and Self-efficacy

Can the Spontaneous Electroencephalography Theta/Beta Power Ratio and Alpha Oscillation Measure Individuals' Attentional Control?

Past studies have shown that spontaneous electroencephalography indicators-namely, the theta/beta power ratio and alpha oscillation-may measure individuals' attentional control processes. However, there is lack of research distinguishing these differences. This study investigated whether the theta/beta power ratio and alpha oscillation were separately related to the objective and subjective criteria of attentional control in eyes-open and eyes-closed conditions. The results showed two main findings: (1) In the eyes-open condition, the theta/beta power ratio at the Fz and Pz electrode sites were significantly negatively correlated with the attentional control scale score; the alpha power at the Pz electrode site was significantly negatively correlated with flanker RT interference effect; (2) In the eyes-closed condition, the alpha power at the Cz and Pz electrode sites were significantly positively correlated with flanker P3d. In summary, this study showed that the eyes-open spontaneous theta/beta power ratio may reflect individuals' beliefs in their attentional control ability, and the alpha oscillation may be related to individuals' attentional control ability.

Distributional analyses reveal the polymorphic nature of the Stroop interference effect: It's about (response) time.

The study addressed the still-open issue of whether semantic (in addition to response) conflict does indeed contribute to Stroop interference (which along with facilitation contributes to the overall Stroop effect also known as Congruency effect). To this end, semantic conflict was examined across the entire response time (RT) distribution (as opposed to mean RTs). Three (out of four) reported experiments, along with cross-experimental analyses, revealed that semantic conflict was absent in the participants' faster responses. This result characterizes Stroop interference as a unitary phenomenon (i.e., driven uniquely by response conflict). When the same participants' responses were slower, Stroop interference became a composite phenomenon with an additional contribution of semantic conflict that was statistically independent of both response conflict and facilitation. While the present findings allow us to account for the fact that semantic conflict has not been consistently found in past studies, further empirical and theoretical efforts are still needed to explain why exactly it is restricted to longer responses. Indeed, since neither unitary nor composite models can account for this polymorphic nature of Stroop interference on their own, the implications for the current state of theory are outlined.

Non-Coding RNAs: Novel Regulators of Macrophage Homeostasis in Ocular Vascular Diseases.

Ocular neovascularization can impair vision and threaten patients' quality of life. However, the underlying mechanism is far from transparent. In all mammals, macrophages are a population of cells playing pivotal roles in the innate immune system and the first line of defense against pathogens. Therefore, it has been speculated that the disfunction of macrophage homeostasis is involved in the development of ocular vascular diseases. Moreover, various studies have found that non-coding RNAs (ncRNAs) regulate macrophage homeostasis. This study reviewed past studies of the regulatory roles of ncRNAs in macrophage homeostasis in ocular vascular diseases.

Association Between Community Elderly Care Services and the Physical and Emotional Burden of Family Caregivers of Older Adults: Evidence from Beijing, China.

The rate of usage of community elderly care services in China is low, and past studies about the effects of these services on caregiver burden domestically are few. This study used a large sample of Beijing census data (n = 55,634) to examine the impact of these services on caregiver burden. Logistic regression and propensity score matching were used to estimate the effects. The results showed that meal assistance, respite care, and spiritual comfort are all significantly associated with a lower likelihood of perceived emotional burden among caregivers, while only respite care is very significantly associated with a lower likelihood of feeling physically burdened. However, the effects of these services on caregiver burden also depend on the activities of daily living performance and location of residence of the care recipients. The practical implications for policy makers are discussed.

Response of shallow foundations in tire derived aggregate

This study investigates the quasi-static bearing stress-settlement response of shallow foundations in monolithic tire derived aggregate (TDA) layers having a total thickness of 3 m using a large-scale container and loading system. Tests were performed on footings having a range of widths, embedment depths, shapes, and loading inclinations. In tests where tilting was restricted, a clear bearing capacity was not observed for settlements up to 1.2B, where B is the footing width, but in tests where tilting was permitted bearing capacity was observed between settlements of 0.2B to 0.7B. Surface settlements indicate a dragdown response of the TDA adjacent to the footing extending out to more than 3B from the footing center, while settlement plates beneath the footing indicate a zone of influence of induced settlements of 14% at a depth of 4B. While bearing capacity theories for frictional geomaterials provided a reasonable prediction of the bearing capacity of footings in TDA for most tests, the corresponding settlements may be excessive for engineering applications. Accordingly, a correlation was developed between the theoretical bearing capacity and bearing stress at a settlement of 0.1B. A test with sustained loading indicates slight creep settlements with some stress dependency with magnitudes consistent with past studies.