bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elastoplastic analysis of surrounding rock in weakly cemented soft rock roadways and its support practice
Authors: Zhang Jihua , Rui Qiao , Li Xinwei , Yang Yushun , Wang Ge , Chen Jiarui , Shen Wei , Wang Chengwu , Liu Weili 
Published: August 2024

Abstract

The effects of rock softening and shear dilation in the plastic zone are considered to examine the stability of surrounding rock in deep, weakly cemented soft rock roadways. An elastic-soft fracture mechanical model of the surrounding rock is developed, from which the analytical solutions for the stress and displacement fields are derived, providing expressions for the radius of the plastic zone. This analysis assesses the impact of cohesion, internal friction angle, and support force on the stress field, displacement field, and plastic zone radius. The results indicated that the elastic-plastic mechanical model, which considers the softening and shear dilation effects, more accurately represents the deformation characteristics of the roadway's surrounding rock across the zones of elasticity, softness, and fragmentation. As initial cohesion and internal friction angle increase, the surrounding rock's load resistance is enhanced, delaying the emergence and expansion of plastic zones. The elastic-plastic interface moves toward the excavation surface, causing a gradual increase in the circumferential stress at the interface. With increasing cohesion and internal friction angle, the radius of the plastic zone exhibits a non-linear decrease, with the plastic fracture zone diminishing first. The influence of cohesion and internal friction angle on the various zones of surrounding rock is ranked as follows: radius of plastic fracture zone > plastic softening zone > elastic zone. A joint support scheme, incorporating "anchor net and cable injection" with grouting as the core component, is proposed for a project overview of weakly cemented soft rock roadways in the western mining area. This scheme achieves positive outcomes and enhances the safety of roadway construction.
Coulomb Stress Characteristics and Fault Slip Distribution of the 2023 Mw 6.1 Earthquake in Jishishan County (Gansu, China) Based on InSAR Observations
Authors: yu shuyuan , Zhang Shubi , Li Zhejun , Luo Jiaji , Yang Yuanyuan , Ding Juan 
Published: August 2024

Abstract

On December 18, 2024, a Mw 6.1 earthquake occurred in Jishishan County, Linxia Prefecture, Gansu Province. This earthquake is the largest recorded since the establishment of seismic observations on the Laji Mountain fault zone along the northeastern edge of the Tibetan Plateau. This study utilizes Sentinel-1A satellite data to obtain the coseismic deformation field from ascending and descending tracks of the 2023 Jishishan earthquake, using this information to constrain the inversion of the earthquake's fault kinematic parameters and fault slip distribution characteristics. Finally, integrating the characteristics of Coulomb stress changes with regional tectonic background research results, we assess the seismic hazard of the region. The study indicates that the deformation field generated by this earthquake is oriented predominantly in the NNW direction, with the coseismic deformation from both ascending and descending tracks mostly exhibiting uplift. The maximum line-of-sight (LOS) displacement for the ascending track is approximately 6 cm, while for the descending track it is about 6.7 cm. The results of slip testing on the coseismic fault suggest that both east-dipping and west-dipping fault geometric models can adequately explain the parameters of the fault that caused this earthquake. Based on aftershock relocation and comprehensive analysis of the regional tectonic background, the study concludes that the rupture likely occurred on a northeast-dipping fault, potentially a concealed reverse fault with an NNW orientation located along the southern margin of Laji Mountain. Calculations of static Coulomb stress changes indicate that the occurrence of the 2023 Jishishan earthquake has increased the risk of future seismic events along segments of the NWW-oriented southern and northern margins of the Laji Mountain fault, as well as to the east of the epicenter along the Xiqinling northern fault and the Daotanghe-Linxia fault.
T Cell Exhaustion Methylation Signature Drives Differential Immune Responses in Glioblastoma
Authors: Chen Feng , Qian Wen-Bo , Chen Zhen-Hua , Qian Jun , Luo Chun 
Published: August 2024

Abstract

Background Methylation-related signatures play crucial roles in tumorigenesis and progression. However, their roles in the immune response in primary glioblastoma (GBM) remains unclear.Methods We analyzed the differential expression of specific members of T cell exhaustion-related pathways in GBM from the perspective of T cell exhaustion. We further screened for significantly negatively correlated methylation sites as candidate methylation markers for T cell exhaustion. Using consensus clustering, we divided the samples into two categories with significant differences in overall survival (OS). We then performed univariate and multivariate Cox regression analyses to construct the T Cell Exhaustion Methylation (TEXM) signature. Finally, we confirmed that this signature served as an independent prognostic factor, and further characterized it in terms of drug resistance and immunotherapy.Results We identified 95 significantly differentially expressed T cell exhaustion-related genes and 51 methylation markers associated with T cell exhaustion. The cancer samples were classified according to methylation site markers, thus indicating two subtypes with significant differences in OS: subtype A and subtype B. Tumor scores, stromal scores, tumor purity, and ESTIMATE scores all showed significant differences between subtypes (P < 0.05). Univariate Cox regression analysis identified five methylation sites significantly associated with OS, and multivariate Cox regression analysis was used to construct the TEXM signature model by using these five methylation sites. Survival analysis, based on calculating the TEXM signature scores of tumor samples and using the median score to divide them into high and low score groups, revealed significant OS differences between high score group and low score group in the validation set. However, comparison of the TEXM signature with clinical TEXM Additionally, drug sensitivity significantly differed between the high and low TEXM signature score groups, with the high score group showing higher drug resistance and poorer prognosis. The tumor immune state, as predicted with TIP, revealed significant differences in antitumor immune scores between the high and low TEXM signature score groups. Finally, we identified 43 significantly differentially regulated metabolism-associated biological processes.Conclusion The epigenetic methylation-related TEXM signature plays a key role in driving differential immune responses in GBM.
Self-deception, Psychological Capital and Depression in Normal University Students: A Cross-lagged Analysis
Authors: Chen Yuxia , Wahab Rozita Binti , Jaladin Rafidah Binti Aga Mohd 
Published: August 2024

Abstract

University students are particularly vulnerable to depression. This study examines the correlation and causation between self-deception, psychological capital, and depression in a sample of students from Chinese normal university and assumes that self-deception, like psychological capital, is a positive psychology variable to supply rational interventions for the precaution of potential depressive normal university students. A 3-month follow-up mental health study was conducted on 260 Chinese normal university students, using Self-Deceptive Enhancement scale, Center of Epidemiological Studies Depression Scale and Positive Psychological capital Questionnaire. The Cross-lagged panel Model was employed to test the causal relationship between self-deception, psychological capital, and depression. The prevalence of depression among the average college student is as high as 35.0%. The correlation analysis showed that self-deception was positively correlated with psychological capital and negatively correlated with depression, and psychological capital was negatively correlated with depression. The cross-lagged analyses revealed that self-deception could negatively predict depression (β = -0.16, p < 0.01); Psychological capital could negatively predict depression (β= -0.16, p < 0.01); Self-deception could positively predict psychological capital (β = 0.23, p < 0.001) and the reciprocal effect (β = 0.13, p < 0.05) was also observed. The existence of a causal relationship between self-deception, psychological capital and depression, which support the cognitive bias orientation of self-deception and the risk compensation model of psychological capital, and provides a theoretical basis for designing easy-to-administer interventions to alleviate students' depressive symptoms in the classroom.
Resin anchoring reinforcement for multi-stage reaming of a cable bolt in a soft-rock roadway
Authors: Zhao Hongrui 
Published: August 2024

Abstract

In cable bolt reaming and anchoring of a soft-rock roadway tunnel, the cable bolt and its stirring end are in direct contact with the wall of the drilling hole, which can easily damage the structure of the drilling hole. The cable bolt cannot effectively break and stir the resin cartridge in the reaming area. The anchoring force of the cable bolt is low and the deformation of the surrounding rock is large. The characteristics of cable bolt reaming and anchoring in a soft-rock roadway are analyzed systematically. The influence of the cable bolt on the reaming and anchoring performance is calculated and analyzed in terms of cable bolt stirring, anchoring solid strength, pull-out force, cable bolt concentricity, and the influence of the drilling hole wall. A multi-stage reaming and anchoring reinforcement (MRAR) is developed, and the mechanism through which the MRAR strengthens the reaming and anchoring of a cable bolt is analyzed theoretically. Through numerical simulation and laboratory and field experiments, the working performance of the MRAR is verified comprehensively. The results show that the MRAR greatly improves the dynamic stirring action of the cable bolt, compactness and strength of the anchoring solid, drilling performance, concentricity, pull-out force, and pretension. It can ensure to the maximum extent that all the resin cartridge in the reaming area is stirred, reacted, and firmly bonded with the hole wall. It greatly improves the reaming and anchoring and roof deformation control of the cable bolt in the soft-rock roadway. This technology has practical significance for improving the reaming and anchoring of a cable bolt and the bearing capacity of the surrounding rock in a soft-rock roadway tunnel.
Impact of growing media on yield, biochemical, and physiological characteristics of Rheum rhabarbarum L
Authors: Daryadar Mahsa , Matevosyan Artur , Roosta Hamid Reza , Ghorbanpour Mansour , Ghahramanyan Aristakes , Stepanyan Anjelika , Tadevosyan Anna 
Published: August 2024

Abstract

Rhubarb (Rheum rhabarbarum L.) is a popular springtime vegetable known for its vibrant red stalks and tart flavor. This study explores the intriguing biochemical profile of rhubarb and highlights its potential health benefits. Hydroponic systems (volcanic slag and volcanic slag with gravel significantly increased rhubarb yield (both fresh and dry weight) by 2.6-6.0 times compared to traditional soil, especially in June and July. Rhubarb grown hydroponically also produced 1.6-1.8 times more petioles per plant, each with 1.6 times the fresh weight and 1.1 times the dry weight of soil-grown petioles. Compared to soil, hydroponics significantly increased the levels of extractive substances (1.2-3.2 times), flavonoids (1.4-3.7 times), and phenols (1.2-4.0 times). The research evaluated antioxidant activity, with hydroponically grown rhubarb demonstrating superior performance, particularly in the volcanic slag + gravel plants, which exhibited the strongest antioxidant activity. In contrast, the soil-grown plants displayed the lowest antioxidant activity. According to the FRAP analysis, 1 gram of plant dry mass recovered more iron in the soil-grown variant, followed by the volcanic slag variant. These findings suggest that hydroponic systems, especially those using the volcanic slag substrate, hold promise for cultivating rhubarb enriched with health-promoting compounds in the Ararat Valley.
Modulating cancer stem cell characteristics in CD133+ melanoma cells through HIF1α, KLF4, and SHH silencing
Authors: Aktug Huseyin , Ozdil Berrin , Avci Cigir Biray , Kocaturk Duygu Calik , Gorgulu Volkan , Uysal Aysegul , Guler Gunnur , Yavasoglu Nefise Ulku Karabay 
Published: August 2024

Abstract

Malignant melanoma, an aggressive skin cancer derived from melanocytes, contains a subpopulation known as cancer stem cells (CSCs), with distinct self-renewal and differentiation abilities, setting them apart from non-cancer stem cells (NCSCs). This study aims to examine how CSCs respond to the suppression of their stem cell characteristics through targeted gene silencing of HIF1α, KLF4, and SHH within the context of the extracellular matrix, with a particular focus on Matrigel. Silencing targeted genes individually induced distinct changes in CSCs behavior, revealing novel therapeutic targets through analysis of gene expression, protein levels, and cell cycle dynamics. A comparison between melanoma CSCs and NCSCs revealed significant shifts in SHH signaling, epigenetic markers, differentiation, migration, and vascularization genes. Specifically, CSCs exhibited elevated levels of SHH, Gli1, and HDAC9, while NCSCs showed increased expression of Mif. Our findings highlight the emergence of a unique cellular phenotype following gene silencing, distinct from both CSCs and NCSCs. Diverse signaling pathways underlie this phenomenon, offering valuable insights for development of melanoma therapies.
Dementia special care units in nursing homes: a revised program theory resulting from a theory-driven evaluation
Authors: Adlbrecht Laura , Wallner Martin , Bartholomeyczik Sabine , Mayer Hanna 
Published: August 2024

Abstract

Background: People with dementia often receive care in dementia special care units of nursing homes. The concept of these units vary considerably. Knowledge about the effects and mechanisms of action of dementia special care units is limited. The aim of the study was to evaluate a specific care concept of a dementia special care unit in long-term care. In this paper, we present the results of the evaluation study in the form of a revised program theory. The aim was to describe the components of the care concept, its context as well as its mechanisms of impact and outcomes for persons with dementia and the nursing staff members.
Methods: We conducted a theory-driven evaluation resulting in a revised program theory. The revision was based on an initial program theory and the findings of the outcome/process evaluation. The primarily data-driven revision is enriched by theory and further literature. Data analysis followed a two-step process: evaluation of the original program theory and construction of the revised program theory, consisting of an action and a change model.
Results: The action model describes interventions, context, target groups and implementers. The change model details how the program generates outcomes. Structural, organizational and educational elements promote a shared person-centered understanding of care among nurses. A unified understanding of care favors engagement in meaningful activities and social interactions. It also supports early interventions addressing challenging behavior. Mutually reinforcing interventions create positive experiences and maintain the residents’ personhood. The success of the program is largely based on a workplace culture and a leadership style facilitating person-centered ways of working.
Conclusion: The revised program theory highlights the positive effects of the dementia special care unit care concept on staff and residents. It provides starting points for future practice development. Considering the interdependence of interventions, increased promotion of meaningful activities and social interactions seem advisable. Future research should explore whether the mechanisms of action developed for a specific care concept are transferable to a broader program theory for specialized dementia care.
Trial registration: DRKS00011513
Optimized Enhanced Energy Absorption in Polymer Nanocomposites Reinforced with Nano-Clay, Nano-Silica, and Diethylenetriamine
Authors: Taghipoor Hossein , Ghiaskar Ahmad 
Published: August 2024

Abstract

In today's world, where various industries face ever-increasing developments, improving people's lives and preserving their property and lives are important issues in industrial production. One of the most unpleasant events in life is a collision while using the vehicle. Therefore, in recent decades, the high importance of this issue has attracted the attention of many researchers. The present study investigates the energy absorption of polymer nanocomposites with cylindrical and conical structures with different percentages of clay and silica nanoparticles to determine the various effects of nanomaterials and the effect of structure geometry on energy absorption under quasi-static tests. The design of this experiment was done using Design Expert software and the Box-Benken method. The range of changes of nanomaterials is (0-0.4) percent, and diethylenetriamine material with weight percent (1,3,5) has also been used. The results indicate that with the increase of nanomaterial in this range, the energy absorbed by adding nano silica up to the central point, i.e., 0.2%, we have witnessed an increase in energy absorption, and after that, its intensity has decreased. For the nano clay material, a significant increase of up to 0.4% has been observed in this range, and its trend continues with the previous intensity after the central point. However, in diethylenetriamine material, the highest energy absorption at the central point was 0.2%, after which a downward trend was observed. Also, in the investigation of the geometry of the structure, it was found that cone-shaped structures have higher energy absorption.
Post-COVID Educational Leadership: Emerging Models and Styles for a New Era
Authors: Khawaja Sarwar , Karimi Hengameh 
Published: August 2024

Abstract

A compelling vision, goals to go along with it, and a suitable plan for implementation, observation, and review are all necessary components of modern educational leadership, which is widely regarded as essential for boosting an institution's effectiveness and acting as a catalyst for change and innovative strategy. The COVID-19 pandemic has caused disruptions to the delivery of educational services, highlighting weaknesses in the leadership theory behind schools and universities. The majority of institutes' adoption of suitable crisis management strategies to swiftly adapt to a new reality and effectively address upcoming difficulties at both the administrative and instructional levels was mostly responsible for these failures. Despite the idea of crisis management having been successfully applied in various types of crises and extensively developed theoretically, there is a notable lack of empirical research in this area, indicating that the field of educational leadership has not given it consistent attention. This study bridges the research gap by employing the PRISMA methodology to build a systematic review of scholarly articles published during 2019 and 2022. Following the unstable leader, the paper discusses the challenges faced, the crisis management strategies employed, and the personality attributes most commonly associated with effective crisis leadership during the COVID-19 time frame.
Influence of the structural factors on the photoluminescence properties of polyaniline derivatives
Authors: Andriianova Anastasia N. , Petrov Ivan S. , Latypova Lyaysan R. , Mustafin Akhat G. 
Published: August 2024

Abstract

Introduction of a substituent into the aromatic ring of polyaniline (PANI) is one of the most popular methods of polymer modification. In this connection, the photoluminescent properties of a wide range of PANI derivatives have been investigated in the present work: ortho-alkenyl substituted PANI derivatives, with different dopants, copolymers of aniline and its substituted analog. The presented results demonstrate that the modification of PANI by introducing a substituent into the aromatic ring contributes not only to the improvement of solubility but also to the increase of photoluminescence intensity. Comparative analysis of photoluminescence spectra of the investigated series of polymers showed that the presence of a bulk substituent in the aromatic ring of the polymer chain leads to an increase in the luminescence intensity due to steric hindrance.
Riverbank plastic distributions and how to sample them
Authors: Tasseron Paolo F. , Emmerik Tim H.M. van , de Winter Winnie , Vriend Paul , Ploeg Martine van der 
Published: August 2024

Abstract

As plastic pollution exists in aquatic ecosystems globally, monitoring its abundance and distribution has become crucial for understanding transport pathways, sources, sinks, and impacts. Riverbanks are accumulation zones for plastic, but the selection of monitoring methods is constrained by research goals, available resources, and site-specific conditions. This diversity in approaches has led to disparate datasets, highlighting the need for standardized monitoring protocols. Here, we study the spatial distribution of plastic at the riverbank scale, quantify the uncertainty of existing riverbank methods, and provide recommendations for improved monitoring based on the balance between uncertainty loss and increase in effort. We measured riverbank plastic abundance at eight Dutch riverbanks, categorizing the items using 108 item categories (River-OSPAR). For every riverbank, an area of 100 by 25 meters was subdivided into five-by-five-meter squares, resulting in 100 individual monitored sub-areas. We found riverbank plastic exhibited high spatial variability, with deposition patterns ranging from parallel to the waterline to clustered, random, or uniform (Moran's I between -0.050 and 0.301). Individual measurements from diverse sampling protocols are 5-49 times less accurate than estimates derived from extensive sampling, highlighting the diminishing impact of specific methods with increased data collection. Lastly, our findings suggest that increasing the sampling area quickly reaches diminishing returns in terms of accuracy. Reducing the sampled area by 80% only increases the uncertainty in estimating the true plastic density by 20%. While standardized protocols are essential for data comparability, a rigid, uniform sampling approach may be less efficient and resource-intensive than a flexible (step-wise) strategy that adapts to local conditions. By demonstrating that extensive sampling can mitigate the differences between unique sampling protocols, this study promotes a shift towards flexible and efficient riverbank plastic monitoring, ultimately accelerating global efforts to combat plastic pollution.