bluuebunny/crossref_metadata_2025 huggingface dataset:
IOT BASED SMART HOME SIMULATION (INTERNET OF THINGS)
Authors: Ardianto Yeheskiel Hency , Widiasari Indrastanti Ratna
Published: December 2024

Abstract: The development of Internet of Things (IoT) technology has significantly impacted life, particularly in creating more efficient and secure smart homes. Smart homes integrate various electronic devices to enhance comfort and energy efficiency. However, cost, integration complexity, and security issues remain. This study will simulate an IoT-based smart home system to analyse and evaluate device performance before real-world implementation. The simulation method involves testing connectivity and evaluating delay and packet loss using the ping method on each device. Results show the highest delay on CCTV devices at 41.8 ms and the lowest on motion detector 2 at 32.8 ms, with 0% packet loss. According to TIPHON standards, the network is rated excellent with an index of 4. The designed smart home system demonstrates optimal performance and is feasible for implementation but requires further development in configuration using AI and machine learning technologies.            Keywords: internet of things; simulation; smart home; testing  Abstrak: Perkembangan teknologi Internet of Things (IoT) telah membawa perubahan signifikan dalam kehidupan, terutama dalam pengembangan rumah pintar (smart home) yang lebih efisien dan aman. Smart home mengintegrasikan berbagai perangkat elektronik untuk meningkatkan kenyamanan dan efisiensi energi. Meskipun demikian, tantangan seperti biaya, kompleksitas integrasi, dan isu keamanan masih ada. Penelitian ini bertujuan untuk mensimulasikan sistem smart home berbasis IoT guna menganalisis dan mengevaluasi kinerja perangkat sebelum implementasi nyata. Metode simulasi yang digunakan melibatkan pengujian konektivitas dan evaluasi delay serta packet loss dengan metode ping pada setiap perangkat. Hasil menunjukkan delay tertinggi pada perangkat CCTV sebesar 41.8 ms dan terendah pada motion detector 2 sebesar 32.8 ms, dengan packet loss 0%. Berdasarkan standar TIPHON, jaringan dinilai sangat baik dengan indeks 4. Sistem smart home yang dirancang menunjukkan kinerja optimal dan layak diimplementasikan, namun masih memerlukan pengembangan lebih lanjut dalam konfigurasi menggunakan teknologi AI dan machine learning.  Keywords: internet of things; pengujian; simulasi; smart home
THE STATE OIL REFINERY IN DROHOBYCH (1919–1939)
Authors: MASYK Roman
Published: December 2024

The importance of the state oil refinery «Polmin» in Drohobych for the economy of interwar Poland has investigated. The state of the enterprise at the time of its takeover by the Polish authorities has been determined. The management of the refinery, its subordination, finances, and the participation of state bodies in the development of the enterprise have been analysed. Visions of the role of «Polmin» in different groups of entrepreneurs involved in the oil business in Galicia have been highlighted. It is found that the majority of firms based on Polish capital proposed that this enterprise should remain an instrument of the government’s oil policy and pay less attention to its profitability. At the same time, the government was trying to develop the state oil refinery as a commercial enterprise. The relations between «Polmin» and foreign oil firms that dominated Galicia at the time have been traced. It is stated that the state-owned refinery took an active part in monopoly associations of large oil refineries, which often undermined its independence and reduced its profitability.

The ways of supplying crude oil to the state-owned plant have analysed. It is noted that the company mostly processed raw materials from small oil producers («pure producers») owned by local industrialists. «Polmin’s» relations with them have been traced. Attempts of the state-owned plant to produce crude oil on its own have been noted. The dynamics of «Polmin’s» participation in the trade of oil products on the Polish and foreign markets have been analysed. It is found that this enterprise continued to be the largest oil refinery in interwar Poland. Despite the government's attempts to run «Polmin» like a commercial enterprise, it continued to use the plant as a means of state control over the entire oil industry in Galicia. In this way, the Polish authorities did not allow foreigners to completely take over the industry and allowed local industrialists to engage in the oil business.

Keywords: oil refinery, Galicia, interwar Poland, economy, Drohobych, Boryslav field.
NARRATIVES ABOUT THE DEPORTATION FROM THE POLISH-UKRAINIAN BORDER OF PARTICIPANTS OF THE DISSIDENT MOVEMENT: MARIA HEL, LYUBOV WOZNIAK-LEMYK AND HANNA MYKHAILENKO
Authors: ARTYMYSHYN Yuliia
Published: December 2024

This paper analyzes the memoirs of dissident women Maria Hel, Lyubov Wozniak-Lemyk, and Hanna Mykhailenko, who originated from Zakerzonia. It examines their experiences of deportation, the ways in which these experiences are represented, and the impact of forced displacement on their life choices. The memoirs emphasize the women’s involvement in the national liberation and human rights movements. However, the narratives also reflect on life in the Polish-Ukrainian borderlands, the social and cultural activities of the Ukrainian community during the interwar period, and memories of family members' participation in the OUN and UPA. The content of the memoirs of women dissidents about deportation includes stories about the immediate course of forced deportation, subsequent living conditions, difficulties of a material and household nature, the reasons and prerequisites for deportation are singled out, with mentions or a brief retelling of official orders. Maria Hel and Hanna Mykhailenko place primary responsibility for the deportations on Soviet authorities, while also acknowledging the inter-ethnic Polish-Ukrainian conflict and the Ukrainian underground movement in their native regions.

Lyubov Wozniak-Lemyk, who moved to Lviv in 1920 and lived there until the outbreak of Second World War, was an active participant in the Ukrainian national liberation movement, being a member of Plast and the OUN. His familiarity with the Trans-Curzonia region helped her craft an underground identity, and that she used stories of deportation as a means of protection from Soviet special services.

The paper concluded that the experience of forced deportation from the Polish-Ukrainian border did not prevent these women from opposing the Soviet regime or engaging in further political and human rights activism. Instead, it is hypothesized that forced migration, combined with their families’ active involvement in the national liberation movement of the 1930s and 1940s, influenced their life trajectories.

Keywords: women, dissidence, Ukraine, national liberation movement, human rights movement, deportation from the Polish-Ukrainian border, Zakerzonia.
NATO SUMMITS AND UKRAINE: ANALYSIS OF POLITICAL DIALOGUE AND MEMBERSHIP PROSPECTS IN THE ALLIANCE
Authors: RUDA Oksana
Published: December 2024

The article highlights the progression of political dialogue between Ukraine and NATO at the organization's summits from 2014 to 2023, examining its impact on Ukraine’s membership prospects. It demonstrates that throughout these summits, Ukraine gained substantial support from NATO member countries regarding its sovereignty, territorial integrity, and right to self-determination, which significantly bolstered Ukraine's international backing amid its military conflict with Russia.

In the context of the Russian-Ukrainian war, the Euro-Atlantic integration of our country has acquired special importance, since the security of the region is a priority task for both sides. The evolution of the political dialogue between Ukraine and the Alliance on the sidelines of the summits was considered with an emphasis on such key issues as security, defense capability, and strategic interests of the event participants. In this context, the results of the political debates and decisions taken at the summits related to security and stability in Central and Eastern Europe are analyzed. These decisions had a significant impact on the geopolitical map of the region, as well as on Ukraine’s strategic plans regarding its international status and security. Attempts to resolve security issues at the summits, including political support, provision of military assistance, and the organization of military exercises, were important for Ukraine’s strategic planning in the face of Russian military aggression. Attendance at summits and participation in partnership programs allowed the Ukrainian authorities to maintain a dialogue with the members of the Alliance and continue to take steps to improve their military, political, and economic structures in accordance with the organization’s standards. The North Atlantic Alliance summits served as an important mechanism for Ukraine in ensuring security and support in the conditions of the Russian-Ukrainian war, as well as for the implementation of its strategic goals in the direction of Euro-Atlantic integration.

Keywords: Ukraine, North Atlantic Treaty Organization, Russian-Ukrainian war, NATO summits, Euro-Atlantic integration, political support, military aid.
CULTURAL AND EDUCATIONAL ACTIVITIES OF MYKHAILO HRUSHEVSKY DURING THE TIME OF EMIGRATION: MODERN HISTORIOGRAPHIC RECEPTION
Authors: PAVLOS Ivona Ewa
Published: December 2024

Based on the analysis of diverse historiographical sources, the article reconstructs the reception of M. Hrushevsky’s cultural, educational, and scientific-pedagogical activities during his emigration, as reflected in Ukrainian studies from the late 20th century to the early decades of the 21st century. Reconstructing modern historiographical images of the cultural and educational work of the prominent historian during 1919-1923, the growing interest in this aspect of his national service during the last thirty years has been proven, in terms of volume and number of subjects. The author indicated that modern researchers, without the diaspora experience of the cultural and educational Hrushevsky studies, conducted considerable heuristic work and, for the first time, outlined the multifaceted nature of M. Hrushevsky's enlightening activity during his emigration wanderings. As a result, fairly fact-saturated reconstructions of his didactic work have emerged (V. Masnenko, V. Ulyanovskyi, I. Matyash) as well as lecture and popularization activity (V. Potulnytskyi, A. Sadov, D. Sudyn), culturally aware journalistic work (A. Zhukovsky, S. Pankova) and scientific popularization (M. Kapral, A. Felonyuk, V. Telvak). The cultural and educational Hrushevsky studies of that time is in the "shadow" of his scientific and, especially, social and political activity. This often complicates the independent study of relevant issues, which leads to fragmentation in the reconstruction of the scientist's cultural and educational service. Therefore, an urgent task is an independent comprehensive study of the above-mentioned subjects, which will allow approaching the ripe problem of the synthesis of cultural and educational practices of M. Hrushevsky as an organic component of his intellectual biography.

Keywords: M. Hrushevsky, emigration era, cultural and educational activity, modern Ukrainian historiography, reception.
A Generalized Autoregressive Conditional Heteroscedasticity GARCH for Forecasting and Modeling Crude Oil Price Volatility
Authors: Osho Gbolahan Solomon
Published: December 2024

This current study explores the application of Generalized Autoregressive Conditional Heteroskedasticity (GARCH) models to forecast and model crude oil price volatility. Crude oil is a vital commodity whose price fluctuations significantly impact global economies, energy markets, and strategic decisions of both National Oil Companies (NOCs) and International Oil Corporations (IOCs). Using the GARCH(1,1) and GARCH(1,2) models, this study evaluates the effectiveness of these models in capturing the dynamic nature of oil price volatility. The findings indicate that while both models fit the data well, the GARCH(1,1) model is preferred due to its parsimonious nature and comparable forecast accuracy. Despite including an additional lag in the GARCH(1,2) model, it did not significantly outperform the GARCH(1,1) model in predictive performance. The study further analyzes the residuals and autocorrelation characteristics, highlighting the potential for model refinement. The study underscores the importance of selecting an appropriate model complexity, incorporating external factors, and exploring advanced methodologies to enhance forecast accuracy. These insights are critical for developing effective risk management strategies and informing policy decisions in volatile crude oil markets.
Information Technology and Electronic Commerce Investments, Time Trends of the Speeds of Adjusting the Actual Toward the Maximum Pay, and Chief Executive Officer Compensation
Authors: Lin Winston T. , Chen Yueh H.
Published: December 2024

This research analyzes the effects of information technology (IT) and e-commerce (EC) investments and trends of the speeds of adjusting the observed toward the desired CEO pay in US firms, based on the adjustment model and its associated adjustment valuation (AV) approach, where the adjustment speeds are assumed dynamic and variable. The findings include: the speeds of adjusting the observed toward the unobserved compensation are fast; either IT or EC appearing alone or jointly impacts CEO compensation; the trends of adjustment speeds are nonlinear and nonstationary; and overall, the US CEOs tend to underpay during the period under study; among others.
A Content Analysis of the Modernization of Regulation S-K Items 101, 103, and 105
Authors: Swift Orry , Colon Ricardo
Published: December 2024

In 2020, the U.S. Securities and Exchange Commission (SEC) adopted amendments to modernize the disclosure requirements of Regulation S-K Items 101, 103, and 105. These amendments aim to enhance the readability of disclosure documents and provide investors with more relevant information. This study conducts a content analysis of the modernized disclosure items to assess the extent and nature of the changes implemented. A sample of annual reports filed before and after the amendments was examined to determine whether the SEC meets its stated goals of improving the readability of disclosure documents and discouraging repetition and immaterial information. We conclude that the stated SEC goals for modernization were not met in terms of textual characteristics. These findings provide insights into the effectiveness of the SEC's efforts to update disclosure rules and improve investor’s informational value.
American Left-Behind Children Oral History
Authors: Zhang Yujie Bailey
Published: December 2024

This paper examines emotional resilience, and independence in “left behind children,” defined as those growing up with one or more parents working and living away from home. In considering existing literature on the subject, as well as drawing from oral interviews conducted, this paper suggests that “left behind children” are indeed more emotionally resilient and independent than their peers who do not fall into this category. The participants in this study are five high-school students, two from China and three from America, who grew up with one or more parents living outside of the household. This research complicates broader assumptions regarding “left behind” identity, a term typically associated with low socioeconomic rural Chinese children of migrant workers. The findings of this paper highlight the interviewees’ minimal emotional distress and relatively apathetic dispositions toward their circumstances, challenging canonical assumptions of adverse mental and physical effects.
Optimal control and cost-effectiveness analysis for bacterial meningitis disease
Authors: Belay Malede Atnaw , Abonyo Jeconia Okelo , Alemneh Haileyesus Tessema , Engida Habtamu Ayalew , Ferede Melkamu Molla , Delnessaw Samuel Abebe
Published: December 2024

In this study, we developed an optimal control deterministic model for the dynamics of bacterial meningitis disease. The objective was to investigate the efficiency and cost-effectiveness of the three controls (prevention, treatment, and screening) in curtailing the spread of bacterial meningitis. To accomplish this, we applied Pontryagin's maximum principle to derive the optimality system. We examined different combination strategies to investigate the effect of the interventions on the spread of bacterial meningitis. We used an incremental cost-effectiveness ratio (ICER) to examine which control technique was the most successful. The simulation results show that combining prevention and screening is the most cost-effective strategy. The objective function and the incremental cost-effectiveness ratio further support this result, indicating that maximum utilization of prevention and screening is required for the entire period.
Composition and antimicrobial activity of hydroalcoholic extracts of Pleurotus eryngii var. ferulae and P. eryngii var. elaeoselini
Authors: Polito Flavio , De Martino Laura , Mirabile Giulia , Venturella Giuseppe , Gargano Maria Letizia , De Feo Vincenzo , Elshafie Hazem S. , Camele Ippolito
Published: December 2024

Background

The basidiomycetes Pleurotus eryngii var. ferulae Lanzi and P. eryngii var. elaeoselini Venturella et al. belong to the P. eryngii species complex, acting as facultative biotrophs in association with members of Apiaceae family, i.e., Ferula communis L. and Elaeoselinum asclepium L., respectively. The consumption of these fungi has rapidly increased in recent decades, not only thanks to their nutritional properties and pleasant flavor, but also for their bioactive and medicinal properties.

Methods

A quantitative study of their hydroalcoholic extracts was carried out by liquid chromatography-mass spectrometry. The potential antimicrobial activity of the extracts was also tested against some phytopathogenic bacteria [Clavibacter michiganensis and Bacillus megaterium (Gram-positive), Pseudomonas viridiflava, Xanthomonas campestris, and Escherichia coli (Gram-negative)] and fungi (Aspergillus fumigatus, Penicillium italicum, Monilinia laxa, Botrytis cinerea, Cadophora sp., and Sclerotinia sclerotiorum).

Results

The chemical analysis allowed the identification of secondary metabolites belonging to different classes, as flavonoids, organic acids, amino acids, carbohydrates, vitamins, nucleic acids, fatty acids, and triterpenoids. Both extracts demonstrated antimicrobial activity against of the most tested microorganisms.

Conclusion

The results can broaden the knowledge on the possible use of these fungal species in the agricultural sector.
Unravelling the mechanisms causing murepavadin resistance in Pseudomonas aeruginosa: lipopolysaccharide alterations and its consequences
Authors: Hernández-García Marta , Barbero-Herranz Raquel , Bastón-Paz Natalia , Díez-Aguilar María , López-Collazo Eduardo , Márquez-Garrido Francesc J. , Hernández-Pérez José María , Baquero Fernando , Ekkelenkamp Miquel B. , Fluit Ad C. , Fuentes-Valverde Víctor , Moscoso Miriam , Bou Germán , del Campo Rosa , Cantón Rafael , Avendaño-Ortiz José
Published: December 2024

Introduction

Murepavadin is an antimicrobial peptide (AMP) in clinical development that selectively targets Pseudomonas aeruginosa LptD and whose resistance profile remains unknown. We aimed to explore genomic modifications and consequences underlying murepavadin and/or colistin susceptibility.

Methods

To define genomic mechanisms underlying resistance, we performed two approaches: 1) a genome-wide association study (GWAS) in a P. aeruginosa clinical collection (n=496), considering >0.25 mg/L as tentative cut-off of murepavadin acquired resistance; 2) a paired genomic comparison in a subset of 5 isolates and their isogenic murepavadin-resistant mutants obtained in vitro. Lipid-A composition, immunogenicity and cathelicidin and indolicidin effects on bacterial growth were also tested in this last subset of isolates. Murepavadin MICs were determined in ΔlpxL1 and ΔlpxL2 knock-out mutants obtained from a auxotroph PAO1 derivative.

Results

GWAS revealed a missense variant (A→G p.Thr260Ala in the hisJ gene) associated with murepavadin resistance although both resistant and susceptible strains harbored it (21% and 12% respectively, OR=1.92, p=0.012 in χ² test). Among the isolate subset, murepavadin-resistant mutants with deletions in lpxL1 and lpxL2 genes showed lower abundance of hexa-acylated lipid-A (m/z 1616, 1632). 4-aminoarabinose addition was found only in colistin-resistant isolates but not in the other ones, irrespective of murepavadin susceptibility. Accordingly, ΔlpxL1 and ΔlpxL2 mutants exhibited higher murepavadin MICs than parental PAO1 auxotroph strain (2 and 4 vs 0.5 mg/L respectively). Lipopolysaccharide from murepavadin-resistant mutants triggered lower inflammatory responses in human monocytes. Those with lpxL mutations and hexa-acylated lipid-A loss also exhibited greater growth reduction when exposed to host-derived AMPs cathelicidin and indolicidin.

Discussion

High murepavadin-resistance seems to be linked to lpxL1 and lpxL2 mutations and lower hexa-acylated lipid-A, corresponding to lower inflammatory induction and higher susceptibility to host-derived AMPs. Although GWAS identified one variant associated with the murepavadin-resistant phenotype, data revealed that there was no unique single genetic event underlying this phenotype. Our study provides insight into the mechanisms underlying murepavadin susceptibility.
Rising challenges in periprosthetic joint infections: a focus on rare pathogens and their clinical implications
Authors: Lyu Jianhua , Huang Jiagu , Huang Jiexin , Hu Hongxin , Wang Qijin , Ding Haiqi , Li Hongyan , Fang Xinyu , Zhang Wenming
Published: December 2024

Objectives

The study aimed to evaluate differences in clinical characteristics and treatment outcomes of periprosthetic joint infection (PJI) attributed to rare versus common pathogens.

Methods

Data on PJI patients who underwent hip or knee arthroplasty at our center from April 2013 to December 2022 were retrospectively collected. Among the 219 enrolled patients, we compared 32 cases of PJI caused by rare pathogens with 187 controls of PJI caused by common pathogens, analyzing demographic information, clinical characteristics, and treatment outcomes.

Results

In demographic data, the Charlson comorbidity index and preoperative invasive procedures were identified as risk factors for rare pathogen PJI. Clinically, the rare pathogen cohort exhibited a significantly higher rate of sinus tract formation compared to those with common bacteria PJI. In terms of laboratory findings, the mean serum C-reactive protein (CRP) was significantly lower in the rare pathogen group. This cohort also had a significantly lower culture positivity rate and a higher rate of polymicrobial co-infections. The median hospital stay was statistically longer for rare pathogen PJI cases than for those with common bacteria PJI. Furthermore, the rare pathogen group required longer antibiotic treatments and had higher rates of antibiotic-related adverse events, although reinfection rates did not significantly differ.

Conclusion

PJI caused by rare pathogens exhibits distinct clinical presentations. With advances in diagnostic techniques such as metagenomic next-generation sequencing (mNGS), optimized culture methods, and an interdisciplinary approach facilitating early targeted treatment, rare pathogen PJIs may achieve outcomes comparable to those of typical cases.
Point-of-care testing diagnosis of African swine fever virus by targeting multiple genes with enzymatic recombinase amplification and CRISPR/Cas12a System
Authors: Cao Shinuo , Ma Dongxue , Xie Jun , Wu Zhi , Yan Haoyu , Ji Shengwei , Zhou Mo , Zhu Shanyuan
Published: December 2024

African swine fever virus (ASFV) infection is causing devastating outbreaks globally; pig farming has suffered severe economic losses due to the ASFV. Currently, strict biosecurity control measures can mitigate the incidence of ASF. Rapid, cost-effective, and sensitive detection of ASFV can significantly reduce disease transmission and mortality. CRISPR/Cas-associated proteins can detect polymorphisms with high specificity and sensitivity, making them ideal for detecting pathogens. In this study, based on CRISPR/Cas12a integrated with enzymatic recombinase amplification (ERA) technology, a CRISPR/Cas12a detection system capable of identifying ASFV E183L, K205R, and C962R gene sequences has been developed. The ERA-CRISPR/Cas12a detection system detected ASFV precisely without cross-reactivity with other porcine pathogen templates and with a sensitivity detection limit of 10 copies per reaction; it takes 60 minutes to complete the detection process. In combination with this integrated ERA pre-amplification and Cas12a/crRNA cutting assay, it provides a rapid, straightforward, sensitive, and specific method for ASFV detection in the field.
Zhuanggu Shubi ointment mediated the characteristic bacteria-intestinal mucosal barrier-bone metabolism axis to intervene in postmenopausal osteoporosis
Authors: Li Xiaoya , Li Ning , Pei Huan , Ren Yu , Li Lei , Sun Lan , Wu Yueying , Yuan Jiali , Ma Yuan
Published: December 2024

Background

Zhuanggu Shubi ointment (ZGSBG) has good efficacy in postmenopausal osteoporosis (PMO), but the mechanism of efficacy involving gut microecology has not been elucidated.

Objective

This study investigated the mechanism of ZGSBG in regulating gut microecology in PMO.

Methods

The bilateral ovarian denervation method was used to construct a rat model of PMO and was administered ZGSBG. Behavior, bone transformation, gut microbiota, intestinal mucosal barrier, and intestinal inflammatory-related indexes were detected.

Results

After ZGSBG intervention, bone R-hydroxy glutamic acid protein and procollagen type I N-terminal propeptides were significantly upregulated, while C-terminal telopeptide of type-I collagen and tartrate-resistant acid phosphatase-5b were significantly downregulated. Pathological analysis demonstrated an improvement in femoral and colonic structures. The expressions of zonula occludens-1, occludin, claudin-1, and secretory immunoglobulin A in the colonic tissues were significantly elevated, while the levels of tumor necrosis factor-α, interleukin-1β, interleukin-6, and lipopolysaccharides were reduced. Moreover, characteristic bacteria Muribaculaceae and Prevotella were significantly enriched. Furthermore, Muribaculaceae and Prevotella have a positive correlation with intestinal mucosal barrier function and a negative correlation with intestinal inflammatory responses.

Conclusion

ZGSBG promoted bone formation, inhibited bone resorption, regulated gut microbiota, repaired intestinal mucosal barrier damage, and inhibited intestinal inflammatory responses in PMO rats. Muribaculaceae and Prevotella might play positive roles in ZGSBG treatment of intestinal mucosal barrier injury and inflammatory reactions in PMO.
Numerical investigation of bolted rock joints under varying normal stress and joint roughness coefficient conditions
Authors: Wang Zhiyong , Liao Liyun , Guo Shiyi , Zheng Hanfang , Wu Xuezhen
Published: December 2024

Rock masses are formed through long-term, complex geological processes, and the presence of joints significantly reduces their strength and increases their deformation. Rock bolts effectively enhance the strength and stability of rock masses and are extensively utilized for reinforcement. According to field investigations, a significant portion of the damage to bolted rock masses stems from shear deformation at joint surfaces. Moreover, roughness affects friction and surface contact, thus influencing the shear behavior between rock and rock bolts. This study considers two crucial factors affecting the shear characteristics of bolted rock joints: joint surface roughness and normal stress. Using the Particle Flow Code discrete element numerical method, the Barton standard joint profile lines were input to establish numerical models of both unbolted and bolted rock joints for direct shear tests. Results reveal that the peak shear stress and stiffness of both unbolted and bolted rock joints increase with rising normal stress and joint roughness coefficient. The peak shear stress and stiffness of bolted rock joints are notably higher than those of unbolted ones, with a maximum increase of 17.5%. Crack development in bolted rock joints occurs in stages of rapid, slow, and stable development, whereas no distinct slow development stage is observed in unbolted rock joints. Additionally, micro cracks in both unbolted and bolted rock joints are primarily tensile cracks, originating around the joint surface and extending outward with increasing shear displacement. These findings offer valuable insights into the microscopic shear mechanics of bolted rock joints and provide practical references for engineering design and applications in rock reinforcement projects.
Journey to becoming a culturally responsive science educator: reflections about use and barriers from graduate teaching assistants at a Minority-Serving Institution
Authors: McAnally Kaylyn , Barron Hillary A. , Woodruff Isabella , Beaster-Jones Laura , Menke Erik , Kranzfelder Petra
Published: December 2024

Introduction

A pedagogical framework with the aim of dismantling sociostructural disparity and systemic oppression is culturally responsive science teaching (CRST). Although CRST has been linked with improved student empowerment, self-efficacy, and ethnic and academic identity, more research is needed to assess whether graduate teaching assistants (TAs) in college science are familiar with and prepared to engage in CRST. We conducted two training sessions for inclusive teaching practices and CRST during a graduate TA teaching professional development course at a research-intensive Minority-Serving Institution (MSI).

Methods

We collected surveys, written reflections, and session artifacts from five graduate TAs participants and used qualitative methods to generate an understanding of their experiences with inclusive teaching and CRST.

Results

Results from this exploratory study indicated that graduate TAs felt they lacked training in inclusive practices and CRST, but still were intentional in providing their students with individualized attention and tried to make sociopolitical connections in their teaching. Also, they reported using inclusive practices and CRST by encouraging shared student experiences and promoting growth mindsets. A lack of time and training remained a barrier to implementation.

Discussion

These findings can inform future inclusive teaching professional development, which aims to bolster instructor's inclusive and culturally responsive science teaching practices, especially at MSIs.
Analyzing first-semester chemistry students’ transactive talk and problem-solving activities in an intervention study through a quantitative coding manual
Authors: Hauck David Johannes , Steffen Andreas , Melle Insa
Published: December 2024

Introduction

During the COVID-19 pandemic, digital video conferencing formats temporarily became the new norm at universities. Due to social distancing, these environments were often the only way for students to work together. In the present study, we investigated how first-semester chemistry students dealt with new, challenging content, i.e., quantum theories of chemical bonding such as molecular orbital (MO) theory, in such an unfamiliar collaboration environment. Studies in the field of Computer-Supported Collaborative Learning (CSCL) suggest that small groups working on complex tasks are particularly effective when students actively build on the ideas and reasoning of their peers, i.e., when they engage in transactive talk and when they structure their work on a metacognitive level by following typical problem-solving patterns.

Methods

To operationalize these constructs, we developed a coding manual through quantitative content analysis, that we used to analyze a total of N = 77 students working together in 21 small groups on two consecutive tasks: the creation of glossaries and the construction of concept maps on MO theory. Our manual showed very good characteristics in terms of internal consistency and inter-coder reliability. Based on the data obtained, it was possible to not only describe the student’s transactive communication and problem-solving activities, but to correlate it with other variables such as knowledge development in MO theory, which allowed us to compare the two different collaborative phases as well as different treatment groups.

Results and discussion

Students showed a higher proportion of transactivity and problem-solving activities when constructing the concept maps than when creating glossaries. In terms of knowledge gains, a multiple linear regression analysis revealed that students in groups that derived consequences from their collaborative work showed greater improvements than students who did not, although the students’ prior knowledge remained the most influential factor. As for the different treatments, our data did not reveal any noticeable difference when students from a small group worked with either complementary or identical material before collaboration, neither in terms of transactive talk nor problem-solving patterns. All in all, we were able to develop and test a powerful tool to quantify transactive communication and problem-solving activities in a collaborative context.
Loss of Sult1a1 reduces body weight and increases browning of white adipose tissue
Authors: Springer Margherita , Meugnier Emmanuelle , Schnabl Katharina , Hof Kevin Sebastiaan , Champy Marie-France , Sorg Tania , Petit-Demoulière Benoit , Germain Natacha , Galusca Bogdan , Estour Bruno , Vidal Hubert , Klingenspor Martin , Hager Jörg
Published: December 2024

Background and objective

Overweight and obesity affects millions of individuals worldwide and consequently represents a major public health concern. Individuals living with overweight and obesity have difficulty maintaining a low body weight due to known physiological mechanisms which prevent further weight loss and drive weight regain. In contrast, mechanisms which promote low body weight maintenance receive less attention and are largely unknown. To uncover these intrinsic mechanisms, we investigated a human cohort of constitutionally thin (CT) individuals which maintain a low body weight and are resistant to weight gain despite exposure to an obesogenic environment.

Methods

To identify novel genes that contribute to low body weight maintenance, we performed transcriptomics on adipose tissue biopsies collected from CT and normal body weight (NBW) individuals and identified sulfotransferase 1A1 (SULT1A1) as a target for further investigation in mice. Sult1a1 knockout (KO) mice were fed a standard diet to assess the impact of Sult1a1 deletion on metabolic traits. To determine if high-fat feeding recapitulated the CT weight gain resistance phenotype, Sult1a1 KO mice were fed a high-fat diet for 13-weeks. A subset of wild-type and Sult1a1 KO mice from the standard diet were further analyzed for characterization of adipose tissue respiratory capacity.

Results

In comparison to NBW controls, adipose tissue from CT individuals expresses less SULT1A1. Sult1a1 KO mice weigh 10% less at the end of the study period and on a high-fat diet, Sult1a1 KO mice tended to gain less weight and had reduced fat mass at 14-weeks of age. These changes were associated with reduced fasting insulin and lessened adipose tissue inflammation and fibrosis. Subcutaneous adipose tissue from Sult1a1 KO mice on a standard chow diet had elevated leak respiration, uncoupling protein 1 (UCP1) expression and increased expression of a mitochondrial marker, VDAC, associating Sult1a1 deletion to adipose tissue browning.

Conclusions

Our results associate Sult1a1 deletion with a tendency for lower body weight through remodeling of white adipose tissue towards a brown phenotype. The presence of UCP1, the expression of an additional mitochondrial protein and increased respiratory capacity suggest browning of the subcutaneous adipose tissue depot of Sult1a1 KO mice.
Design and implementation of a PV-tied effective inverter with high reliability and low THD for distribution-grid applications
Authors: Nyamathulla Shaik , C. Dhanamjayulu
Published: December 2024

Research has focused on multilevel inverters (MLIs) due to their use in electric vehicles, renewable energy systems, and industrial applications. This paper proposes a new design for a single-phase 21-level asymmetrical MLI for photovoltaic (PV) applications that reduces the number of components, voltage stress, and overall size and cost. Enhanced incremental maximum power point tracking (EINC-MPPT) is used in the PV standalone system to offer a fast dynamic response, track maximum power, and regulate the PV module output voltage. This paper presents a PV-boost DC–DC single-input multi-output (SIMO) converter linked to solar panels to provide supply voltage to the inverter. A level-shifted constant multicarrier sinusoidal pulse width modulation (LSCMSPWM) technique is used to produce a better-synthesized output waveform from the MLI, resulting in low total harmonic distortion (THD) and also meeting IEEE standards. The suggested MLI is simulated in MATLAB/Simulink and tested with a hardware prototype under various load conditions. It is suitable for medium-power and grid-connected renewable energy systems applications. The qualitative and quantitative parameters of the proposed MLI have been evaluated by cost function (CF), number of components, reliability, THD, and total standing voltage (TSV); these parameters are compared with the existing MLIs.
Coordinated optimization of control parameters for suppressing transient overvoltage in wind power DC transmission systems
Authors: Zhao Jie , Dou Jinqiu , Li Ming , Wu Fangjie , Shen Xiaolin , Liang Yilin , Shang Lei
Published: December 2024

With the increasing proportion of new energy in power systems, the instability issues of novel power systems become more prominent. This paper addresses the transient overvoltage problem in wind power DC transmission systems by proposing a method for transient overvoltage suppression based on doubly-fed wind turbines, high-voltage DC transmission systems, and SVC control parameter optimization. The electromagnetic transient model of the wind power DC transmission system is combined with intelligent optimization algorithms through joint invocation to achieve coordinated optimization of control parameters. Case studies validate the effectiveness of the proposed model and method. The results indicate that the improved genetic algorithm, SEGA, proposed in this paper, effectively suppresses overvoltage at the grid connection point of wind turbines. Furthermore, by simultaneously applying coordinated control strategies based on DFIG and SVC and optimizing parameters of HVDC, DFIG, and SVC, transient overvoltage phenomena can be effectively eliminated.
Voltage regulation in distribution networks by electrical vehicles with online parameter estimation
Authors: Lyu Shukang , Han Huachun , Li Jingyan , Yuan Xiaodong , Wang Wenyue
Published: December 2024

The integration of a large number of electric vehicles (EVs) offers a new perspective for providing voltage regulation services for the operation of distribution networks. The flexible charging and discharging capabilities of EVs can help mitigate voltage fluctuations and improve grid stability. In this paper, we utilize EV clusters by controlling the discharging power to realize voltage regulation of distribution networks. We formulate a feedback-based optimization problem with the objectives of minimizing voltage mismatch as well as reducing the cost of voltage regulation services provided by EV clusters. Then we propose an algorithm with online resistance estimation to find the optimal solution without requiring complete information about distribution networks. The convergence of the proposed algorithm is guaranteed by the oretical proof. Numerical results in 33-bus system validate the performance of the algorithm. The results validate the applicability of the proposed approach in distribution networks, highlighting the potential of EV clusters as a flexible and cost-effective solution for voltage regulation.
Does green finance promote the improvement of regional eco-efficiency? Direct and spillover effects
Authors: Zhang Yuze , Zhang Jisong , Liu Yuqing
Published: December 2024

Introduction

Green finance plays a pivotal role in advancing China’s ecological civilization construction and achieving sustainable economic and social development.

Methods

Using panel data from 30 provinces in China from 2009 to 2021, this study applies the entropy weighting method and the super-efficiency slack-based measure (Super-SBM) model to assess the levels of green finance and eco-efficiency in each province. Employing spatial statistical methods such as the spatial standard deviation ellipse (SSDE) and the spatial Markov chain, the study reveals the spatiotemporal evolution characteristics of green finance and eco-efficiency. Additionally, the spatial Durbin model is used to analyze the direct effects, spatial spillover effects, and spatial heterogeneity features of green finance on regional eco-efficiency.

Results

The results show that (1) From 2009 to 2021, green finance and regional eco-efficiency levels exhibited an overall upward trend, though with notable spatiotemporal differences. (2) The direct and spatial spillover effects of green finance on regional eco-efficiency followed a notable inverted U–shaped relationship. However, in most provinces, green finance levels had not yet reached the turning point during the study period, and the impact of green finance on regional eco-efficiency remained largely positive. (3) The effects of green finance on regional eco-efficiency showed considerable structural differences due to regional heterogeneity, with the strongest effects observed in the Eastern regions.

Discussion

This study provides policymakers with strategies to enhance regional eco-efficiency through the development of green finance, offering valuable insights for promoting ecological civilization construction and achieving sustainable development.
Navigating diversity: primer impact on arthropod recovery in molecular environmental monitoring in tropical Amazon
Authors: Penner Fernanda Valente , Lynggaard Christina , Argolo Leandro Araujo , da Silva Yorranna Kelly Rossy , de Oliveira Guilherme Corrêa , Bohmann Kristine , Gastauer Markus
Published: December 2024

Introduction

The urgent need for effective environmental monitoring amid the escalating biodiversity crisis has prompted the adoption of molecular techniques like DNA metabarcoding. Through sequencing of taxonomically informative mitochondrial markers in bulk arthropod samples, metabarcoding allows assessment of arthropod diversity, which is crucial for ecosystem health evaluations, especially in threatened regions like the Amazon. However, challenges such as primer biases and reference database limitations persist.

Methods

Here, we assess the performance of four metabarcoding primer sets, two COI markers (ZBJ-ArtF1c/ZBJ-ArtR2c [Zeale]: 157bp, targeting arthropods, and mlCOIintF/jgHCO2198 [Leray]: 313bp, targeting metazoans) and two 16S markers (Ins16S_1shortF/Ins16S_1shortR [Ins16S]: 150bp, targeting insects, and Coleop_16Sc/Coleop_16Sd [EPP]: 105bp, targeting arthropods, mainly Coleoptera) in amplifying the taxonomic constituents of bulk arthropod samples, collected across different natural and anthropogenic habitats from the Brazilian Amazon biome. To evaluate primer performance, we used the indicators (i) amplification efficiency, (ii) primer specificity, i.e., the amount of non-target sequences, (iii) detected OTU richness, (iv) group coverage and (v) taxonomic resolution. Finally, we (vi) estimated the refinement in taxa recovery by additional amplifications.

Results

Despite lower specificity and contrasting results regarding OTU richness, the primer pairs returning larger fragments showed higher taxonomic resolution (Ins16S) and broader taxonomic coverage (Leray) than Zeale and EPP did. Furthermore, results demonstrated the complementarity of the Leray and the Ins16S primer sets from taxon-dependent studies.

Conclusions

Despite limitations, combining these primers could enhance biodiversity monitoring in the region. Considering incomplete reference gene banks, primers maximizing OTU richness (EPP and Leray) may be the best choice for taxon-independent surveys. These findings underscore the importance of primer selection and highlight the ongoing efforts to refine DNA metabarcoding for robust environmental assessments.
OCRClassifier: integrating statistical control chart into machine learning framework for better detecting open chromatin regions
Authors: Lai Xin , Liu Min , Liu Yuqian , Zhu Xiaoyan , Wang Jiayin
Published: December 2024

Open chromatin regions (OCRs) play a crucial role in transcriptional regulation and gene expression. In recent years, there has been a growing interest in using plasma cell-free DNA (cfDNA) sequencing data to detect OCRs. By analyzing the characteristics of cfDNA fragments and their sequencing coverage, researchers can differentiate OCRs from non-OCRs. However, the presence of noise and variability in cfDNA-seq data poses challenges for the training data used in the noise-tolerance learning-based OCR estimation approach, as it contains numerous noisy labels that may impact the accuracy of the results. For current methods of detecting OCRs, they rely on statistical features derived from typical open and closed chromatin regions to determine whether a region is OCR or non-OCR. However, there are some atypical regions that exhibit statistical features that fall between the two categories, making it difficult to classify them definitively as either open or closed chromatin regions (CCRs). These regions should be considered as partially open chromatin regions (pOCRs). In this paper, we present OCRClassifier, a novel framework that combines control charts and machine learning to address the impact of high-proportion noisy labels in the training set and classify the chromatin open states into three classes accurately. Our method comprises two control charts. We first design a robust Hotelling T2 control chart and create new run rules to accurately identify reliable OCRs and CCRs within the initial training set. Then, we exclusively utilize the pure training set consisting of OCRs and CCRs to create and train a sensitized T2 control chart. This sensitized T2 control chart is specifically designed to accurately differentiate between the three categories of chromatin states: open, partially open, and closed. Experimental results demonstrate that under this framework, the model exhibits not only excellent performance in terms of three-class classification, but also higher accuracy and sensitivity in binary classification compared to the state-of-the-art models currently available.