bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Psychosomatic Traits in Tailored Workup for Anterior Cervical Discectomy and Fusion—A Case Series
Authors: Battistelli Marco , Mazzucchi Edoardo , Muselli Mario , Polli Filippo Maria , Galieri Gianluca , Bazzu Paola , Pignotti Fabrizio , Olivi Alessandro , Sabatino Giovanni , La Rocca Giuseppe
Published: April 2024

Study design: Prospective study. Objective: To evaluate the influence of preoperatively assessed psychosomatic traits on postoperative pain, disability, and quality of life outcomes. Summary of background data: Anterior cervical discectomy and fusion (ACDF) is a widely employed surgical procedure for treating cervical spondylosis. Despite its effectiveness, various studies have reported non-success rates in terms of alleviating disability and pain. Psychological factors have become increasingly recognized as critical determinants of surgical outcomes in various medical disciplines. The full extent of their impact within the context of ACDF remains insufficiently explored. This case series aims to assess the influence of preoperative psychological profiling on long-term pain, disability and quality of life outcomes. Methods: We conducted a prospective cohort study of prospectively collected data from 76 consecutive patients who underwent ACDF with PEEK inter-fixed cages from July 2019 to November 2021. The preoperative psychological traits were assessed using the Symptom Checklist 90 (SCL-90) questionnaire. The Oswestry Disability Index (ODI), Visual Analogue Scale (VAS), Neck Disability index (NDI), EuroQol-5D (EQ-5D), and Short Form-36 (SF-36) were collected preoperatively, one month postoperatively, and at least one year after the surgical procedure. Results: The correlation analyses revealed associations between psychosomatic traits and multiple preoperative and postoperative outcome measures. The univariate analyses and linear regression analyses demonstrated the influence of the Global Severity Index (GSI) over the final follow-up scores for the ODI, VAS, NDI, EQ-5D, and SF-36. The GSI consistently exhibited a stronger correlation with the final follow-up pain, disability, and quality of life outcomes with respect to the correspondent preoperative values. Conclusion: This study highlights the importance of psychosomatic traits as predictive factors for ACDF outcomes and emphasizes their relevance in preoperative assessment for informing patients about realistic expectations. The findings underscore the need to consider psychological profiles in the preoperative workup, opening avenues for research into medications and psychological therapies. Recognizing the influence of psychosocial elements informs treatment strategies, fostering tailored surgical approaches and patient care.
New Insight into Laryngo-Tracheal Surgery: High-Flow Oxygen Therapy to Prevent Early Complications after Surgery
Authors: Trabalza Marinucci Beatrice , Fiorelli Silvia , Siciliani Alessandra , Menna Cecilia , Tiracorrendo Matteo , Massullo Domenico , Venuta Federico , Rendina Erino Angelo , Ciccone Anna Maria , D’Andrilli Antonio , Ibrahim Mohsen , Maurizi Giulio
Published: April 2024

Background: Early post-operative airway management after laryngo-tracheal surgery is crucial. Acute respiratory failure due to glottis’ edema may occur, requiring reintubation. This can prolong ventilatory assistance, jeopardizing anastomosis. To date, only judicious steroid administration and fluid management are available to avoid more invasive procedures. High-flow oxygen therapy (HFOT) is a noninvasive O2 support method providing humidification, warmed air, and Positive End-Expiratory Pressure (AIRVO2). No data about HFOT use to prevent early complications after laryngo-tracheal surgery are reported in the literature. Methods: Between September 2020 and September 2022, 107 consecutive patients who underwent laryngo-tracheal surgery received HFOT (Group A). Data and long-term results were compared with those of 80 patients operated between September 2018 and August 2020 (Group B), when HFOT was not available. All patients were operated in a single center. No pre- or post-operative settings changed, except for HFOT introduction. We analyzed and compared the risk for “delayed” reintubation (unexpected reintubation within the first 24–48 h after extubating/laryngeal mask removal) in the two groups. Results: No patients reported HFOT-related adverse events. The control group (B) presented “delayed” reintubation in 37% (p = 0.027), intensive care unit admission in 67% (p = 0.005) and longer hospital stay (p = 0.001) compared to the HFOT group (A). The minor complications’ rate was 3% in both group and overall mortality was 0%. Re-stenosis was described in 4.6% of the HFOT group, without a statistically significant difference (p = 0.7006). Conclusions: Our study is the first to investigate HFOT use in patients undergoing laryngo-tracheal surgery, potentially representing a consistent innovation in the peri-operative management of these patients. With the limitation of a retrospective series, we would suggest HFOT use for preventing post-operative reintubation rate, possibly reducing ICU admissions and hospital stays.
Prognostic Value of KRAS Mutations in Relation to PDL1 Expression and Immunotherapy Treatment in Adenocarcinoma and Squamous Cell Carcinoma Patients: A Greek Cohort Study
Authors: Tsiouda Theodora , Domvri Kalliopi , Boutsikou Efimia , Bikos Vasileios , Kyrka Krystallia , Papadaki Konstantina , Pezirkianidou Persefoni , Porpodis Konstantinos , Cheva Angeliki
Published: April 2024

Background: Factors that could predict which patients will benefit from Immune Checkpoint Inhibitors (ICIs) are not fully understood. This study aimed to investigate the prognostic value of KRAS biomarker in patients with advanced non-small cell lung cancer (NSCLC) in relation to clinical characteristics, treatment response and PDL1 expression. Patients and methods: The study included 100 patients with NSCLC who received immunotherapy with or without chemotherapy as 1st line treatment. In biopsy samples, the PDL1 biomarker expression rate and somatic mutations of KRAS gene were determined. Results: The mean age of the patients was 67 ± 8 years. Patients were all male and 66% were found with adenocarcinoma whereas 34% with squamous cell carcinoma. The KRAS G12C mutation was found with the highest percentage (73%). In the Kaplan-Meier survival analysis, patients with PDL1 > 49% in combination with a negative KRAS result had a median overall survival of 40 months compared to patients with a positive KRAS result (9 months, p < 0.05). In addition, patients diagnosed with adenocarcinoma, PDL1 < 49% and negative KRAS result had a median overall survival of 39 months compared to patients with a positive result (28 months, p < 0.05). Conclusions: Our study suggests that the presence of KRAS mutations in advanced NSCLC patients has a poor prognostic value, regardless of their PDL1 expression values, after receiving immunotherapy as first-line treatment.
Residual Cardiovascular Risk: Role of Remnants Cholesterol, Monocyte/HDL Ratio and Lipoprotein Ratios on Personalized Cardiovascular Prevention
Authors: Sucato Vincenzo , Comparato Francesco , Ortello Antonella , Galassi Alfredo Ruggero , Novo Giuseppina
Published: April 2024

Cardiovascular diseases represent the leading cause of death in the world and are subject to limitations in prevention strategies despite the use of very effective drugs. The concept of residual risk (RR) is intrinsically related to that of global risk of which it represents a very significant percentage. In the cardiovascular field, the term RR refers to the probability of incurring a major cardiovascular event, despite adequate control of the risk factors present in the individual patient. A significant portion of the RR in the cardiovascular field results from the underestimation of additional risk factors not subjected to adequate intervention such as, for example, triglyceride levels in patients treated for the presence of hypertension and/or hypercholesterolemia. The control of the RR therefore appears as an essential condition for the effective reduction of the global risk profile and is based on an integrated intervention that combines all the different prevention strategies derived from the available evidence and capable of interacting on the basis of a strengthening reciprocal between lifestyle and pharmacological and nutraceutical intervention methods.
Multi-Scenario Simulating the Impacts of Land Use Changes on Ecosystem Health in Urban Agglomerations on the Northern Slope of the Tianshan Mountain, China
Authors: Hua Ziyi , Ma Jing , Sun Yan , Yang Yongjun , Zhu Xinhua , Chen Fu
Published: April 2024

It is of great significance for scientific land use planning and ecological security protection to clarify the impacts of land use changes on an ecosystem’s health. Based on the dynamic evolution of land use and ecosystem health on the Northern Slope of Tianshan Mountain (NSTM) from 2000 to 2020, this study utilized the patch-generating land use simulation (PLUS) model, the Vitality–Organization–Resilience–Services (VORS) model, and the elasticity approach to assess the impacts of land use changes on ecosystem health under four different scenarios: Natural Development Scenario (ND), Farmland Conservation Priority Scenario (FP), Ecological Conservation Priority Scenario (EP), and Urban Development Priority Scenario (UD). The results indicate that (1) land use on the NSTM from 2000 to 2020 was predominantly characterized by barren land and grassland. (2) The overall level of ecosystem health on the NSTM was poor from 2000 to 2020 but showed a gradual improvement trend. (3) Ecosystem health levels vary greatly across scenarios. In general, ecosystem health improves under FP and EP scenarios but deteriorates significantly under ND and UD scenarios. The resilience of ecosystem health varies significantly across different land categories. In the future, optimizing the current land use pattern and refining the ecological protection policy are essential to enhance ecosystem health and services in the NSTM.
A Territorial Strategy for the Activation of Tourism in Low Population Density Heritage Landscapes
Authors: Linares Gómez del Pulgar Mercedes , López Sánchez Marina , Gilabert Cristina Vicente , Antonio-García Miguel Ángel , Sánchez-Salazar Francisco , Tejedor Cabrera Antonio
Published: April 2024

Sustainable and balanced territory development involves management and planning based on the cultural and natural values that characterise it. In contrast to solutions based exclusively on quantitative growth, today, we defend qualitative territorial planning based on specific characteristics and identity what, ultimately, is the heritage content and significance of the territory. In line with these arguments, this article reflects on the need to design territorial planning strategies to activate territories with low demographic density through their heritage and landscape values, specifically referring to rural areas made up of small, scattered population centres. The wide territorial dispersion of these settlements, which represent a large proportion of Latin American and European territory, calls for specific planning and management models and criteria. This article proposes a territorial strategy for these sites aimed at sustainable tourism activation through itineraries and potential identity facilities. The application of the strategy is shown in a pilot case study of the island of Fuerteventura (Canary Islands, Spain).
Extracting Features from Satellite Imagery to Understand the Size and Scale of Housing Sub-Markets in Madrid
Authors: Kenyon Gladys Elizabeth , Arribas-Bel Dani , Robinson Caitlin
Published: April 2024

The following paper proposes a novel machine learning approach to the segmentation of urban housing markets. We extract features from globally available satellite imagery using an unsupervised machine learning model called MOSAIKS, and apply a k-means clustering algorithm to the extracted features to identify sub-markets at multiple intra-urban scales within a case study of Madrid (Spain). To systematically explore scale effects on the resulting clusters, the analysis is repeated with varying sizes of satellite image patches. We assess the resulting clusters across scales using several internal cluster-evaluation metrics. Additionally, we use data from online listings portal Idealista to measure the homogeneity of housing prices within the clusters, to understand how well sub-markets can be differentiated by the image features. This paper evaluates the strengths and weakness of the method to identify urban housing sub-markets, a task which is important for planners and policy makers and is often limited by a lack of data. We conclude that the approach seems useful to divide large urban housing markets according to different attributes and scales.
Living Together, Living Apart: Residential Structures in Late Bronze Age Shirenzigou, Xinjiang
Authors: Ren Meng , Chen Lixun , Xi Tongyuan , You Yue , Tian Duo , Wang Jianxin , Festa Marcella , Ma Jian
Published: April 2024

The spatial organization within ancient settlements offers valuable insights into the evolution of social complexity. This paper examines spatially and chronologically contextualized architectural structures and artifacts uncovered at the Late Bronze Age Shirenzigou site to explore the relationship between the use of space and underlying social dynamics in the Eastern Tianshan Mountains of Xinjiang (China). Central to our findings is a distinctive centripetal compound structure, consisting of a larger non-domestic building surrounded by smaller dwellings. This arrangement, along with the variety and distribution of the artifacts, reveals a complex interplay between private and communal spaces at the site, reflecting a growing complexity within the social fabric of the community. The formation of conglomerates of houses around a central communal structure which occurs across the Tianshan Mountains appears to be a strategic adaptation in response to environmental challenges and socio-political transformations across this region at the end of the second millennium BCE.
Assessment of the Spatial Variation of the Economic Benefits of Urban Green Spaces in a Highly Urbanized Area
Authors: Cho Cheol-Joo , Cheon Kwangil , Kang Wanmo
Published: April 2024

Urban green spaces play a vital role in improving the quality of life and well-being of urban residents. However, their economic benefits in different spatial contexts within highly urbanized areas remain a critical yet understudied topic. This study delves into the economic value of urban green spaces in Cheongju City, Republic of Korea, and investigates the distance-decay features associated with the proximity of green spaces to residential properties. Two spatial econometric models were employed to address these questions: the spatially autoregressive (SAR) model and the generalized additive model (GAM). The SAR model was used to assess the economic benefits of urban green spaces, whereas the distance decay of these benefits was examined with the GAM. Empirical analyses revealed that small-sized parks or forests under 20 ha hold greater economic value when in proximity to residential areas compared to medium-sized parks or forests between 20 and 200 ha. Conversely, large parks or forests over 200 ha appeared to have a disamenity effect, negatively impacting property prices when in close proximity. The GAM’s smooth functions illustrated that the distance-decay effect was shorter for small-sized green spaces and exhibited an inverted U-shape for large-sized ones, resulting in a negative benefit of proximity. Our findings suggest that urban green spaces have a positive impact on property prices, but this effect may not apply uniformly to large-sized parks or forests. Therefore, to enhance the residents’ welfare, green infrastructure policies should prioritize the provision of accessible small- and/or medium-sized parks or forests near residential areas.
Predictive Language Processing in Russian Heritage Speakers: Task Effects on Morphosyntactic Prediction in Reading
Authors: Parshina Olga , Ladinskaya Nina , Gault Lidia , Sekerina Irina A.
Published: April 2024

This study investigates the effect of task demands on the predictive processing of morphosyntactic cues (word class, noun/adjective gender, case, and number) in reading among Heritage Speakers of Russian (N = 29), comparing them with Russian language learners (N = 29) and monolingual Russian speakers (N = 63). Following the utility account of bilingual prediction, we hypothesized that the predictive use of morphosyntactic cues would be more evident in a less-demanding reading cloze task (Experiment 1) than in a more-challenging eye-tracking reading task (Experiment 2), and for cues that RHSs regard as more reliable (word class and number vs. gender and case cues). The results confirmed our predictions: In Experiment 1, Heritage Speakers (and L2 learners) used all cues predictively to generate the upcoming lexical item, with higher accuracy for word class and number cues compared to gender and case cues. In Experiment 2, in contrast to monolingual readers, neither Heritage Speakers nor L2 learners used gender cues on adjectives to anticipate the gender of the upcoming noun. The results are discussed in respect to the interplay between task demands, cue weight, oral fluency, and Russian literacy experience.
Home Language Experience Shapes Which Skills Are Used during Unfamiliar Speech Processing
Authors: Levi Susannah V.
Published: April 2024

Speech mixed with noise and speech that is of an unfamiliar variety both make the task of understanding more difficult. Children are often more negatively affected by these situations than adults. Numerous studies have examined the cognitive and linguistic skills that support spoken language processing. In the current study, we examine the contribution of linguistic exposure and various cognitive and linguistic skills for spoken word recognition of an unfamiliar variety of speech (German-accented English). The Ease of Language Understanding model predicts that working memory skills are needed in the most difficult listening situations. Two groups of school-age children were drawn from a larger sample: those with exposure to multiple languages in the home and those exposed to only English in the home. As predicted, working memory skills predicted performance for children with less varied linguistic experience (those only exposed to English in the home), but not for children with varied linguistic exposure. In contrast, linguistic skills predicted performance for children with more varied linguistic experience, even though the two groups did not differ overall in any of the assessed skills. These findings support the Ease of Language Understanding model of language processing.
The Judicialisation of Parliamentary Privilege in Canada: A Cautionary Tale
Authors: Neudorf Lorne
Published: April 2024

Over the past few decades, Canadian courts have exerted strong influence over the meaning and operation of parliamentary privileges. Starting with a television producer’s Charter rights claim to access a provincial legislature’s public gallery and followed by an employment law claim made by the chauffeur to the Speaker of the House of Commons, the Supreme Court of Canada has articulated an approach under which judges closely scrutinise privileges invoked by legislatures when defending themselves against litigated claims. By applying the doctrine of necessity, Canadian courts make authoritative rulings on what counts as a valid legislative function and the processes and activities needed to fulfil those functions. Canadian courts also require the scope of parliamentary privileges to be pleaded in narrow terms that correspond to the details of a plaintiff’s claim, which has resulted in a hollowed-out conception of privilege over time. In scrutinising the necessity and scope of privilege, Canadian courts have chipped away at the separation of powers. Further, the Canadian approach unjustifiably prioritises the judicial vindication of private rights over the institutional needs of the legislature. Courts in other jurisdictions should reject the Canadian approach and avoid scrutinising the propriety of the exercise of privilege through a necessity test. Instead, courts should engage in a more limited jurisdictional test to confirm the availability of a relevant category of parliamentary privilege in law or historical practice. Judicialising parliamentary privileges weakens the autonomy and vitality of legislative institutions, with the Canadian approach serving as a cautionary tale. Ultimately, the legislature is accountable to the electorate for the exercise of its privileges. To promote fairness and reduce the risk of court interference, parliaments should strengthen the accountability and transparency associated with the exercise of their privileges, including by developing guidelines for their appropriate use.
Chrono-Endocrinology in Clinical Practice: A Journey from Pathophysiological to Therapeutic Aspects
Authors: Mercadante Silvia , Bellastella Antonio
Published: April 2024

This review was aimed at collecting the knowledge on the pathophysiological and clinical aspects of endocrine rhythms and their implications in clinical practice, derived from the published literature and from some personal experiences on this topic. We chose to review, according to the PRISMA guidelines, the results of original and observational studies, reviews, meta-analyses and case reports published up to March 2024. Thus, after summarizing the general aspects of biological rhythms, we will describe the characteristics of several endocrine rhythms and the consequences of their disruption, paying particular attention to the implications in clinical practice. Rhythmic endocrine secretions, like other physiological rhythms, are genetically determined and regulated by a central hypothalamic CLOCK located in the suprachiasmatic nucleus, which links the timing of the rhythms to independent clocks, in a hierarchical organization for the regulation of physiology and behavior. However, some environmental factors, such as daily cycles of light/darkness, sleep/wake, and timing of food intake, may influence the rhythm characteristics. Endocrine rhythms are involved in important physiological processes and their disruption may cause several disorders and also cancer. Thus, it is very important to prevent disruptions of endocrine rhythms and to restore a previously altered rhythm by an early corrective chronotherapy.
Prevalence and Characteristics of Patients with Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: Overlap Syndrome
Authors: Fanaridis Michail , Bouloukaki Izolde , Stathakis Georgios , Steiropoulos Paschalis , Tzanakis Nikos , Moniaki Violeta , Mavroudi Eleni , Tsiligianni Ioanna , Schiza Sophia
Published: April 2024

Overlap syndrome (OVS) is a distinct clinical entity that seems to result in potential cardiovascular consequences. We aimed to estimate the prevalence and risk factors for OVS in OSA patients and analyze clinical and PSG characteristics associated with OVS. In this cross-sectional study, 2616 patients evaluated for OSA underwent type-1 polysomnography (PSG). They were grouped as pure OSA (AHI > 15/h) and OVS patients. Demographics, PSG data, pulmonary function tests and arterial blood gases (ABGs) were compared between groups after adjustments for confounders. OSA was diagnosed in 2108 out of 2616 patients. Of those, 398 (19%) had OVS. Independent predictors of OVS were older age [OR: 5.386 (4.153–6.987)], current/former smoking [OR: 11.577 (7.232–18.532)], BMI [OR: 2.901 (2.082–4.044)] and ABG measurements [PaCO2 ≥ 45 OR: 4.648 (3.078–7.019), PO2 [OR: 0.934 (0.920–0.949)], HCO3− [OR: 1.196 (1.133–1.263), all p < 0.001]. OVS was also associated with prevalent hypertension [OR: 1.345 (1.030–1.758), p = 0.03] and cardiovascular disease [OR: 1.617 (1.229–2.126), p < 0.001], depressive symptoms [OR: 1.741 (1.230–2.465), p = 0.002] and nocturia [OR: 1.944 (1.378–2.742), p < 0.001], as well as with indices of OSA severity. Disturbances in sleep architecture were more prominent in OVS expressed by lower %N3 and REM% and higher arousal index. Our data suggest that OVS is prevalent among OSA patients, with distinct clinical and PSG characteristics. These characteristics could be utilized as predictive factors for early identification and further evaluation of these patients towards desirable patient-reported outcomes.
Exploring the Potential of Micro-Immunotherapy in the Treatment of Periodontitis
Authors: Ferrà-Cañellas Maria del Mar , Garcia-Sureda Laura
Published: April 2024

Periodontitis, characterized by the progressive destruction of dental support tissues due to altered immune responses, poses a significant concern for public health. This condition involves intricate interactions between the immune response and oral microbiome, where innate and adaptive immune responses, with their diverse cell populations and inflammatory mediators, play crucial roles in this immunopathology. Indeed, cytokines, chemokines, growth factors, and immune cells perform key functions in tissue remodeling. Focusing on periodontal therapies, our attention turns to micro-immunotherapy (MI), employing low doses (LDs) and ultra-low doses (ULDs) of immunological signaling molecules like cytokines, growth factors, and hormones. Existing studies across various fields lay the groundwork for the application of MI in periodontitis, highlighting its anti-inflammatory and regenerative potential in soft tissue models based on in vitro research. In summary, this review underscores the versatility and potential of MI in managing periodontal health, urging further investigations to solidify its clinical integration. MI supports an innovative approach by modulating immune responses at low doses to address periodontitis.
RNA-Seq of an LPS-Induced Inflammation Model Reveals Transcriptional Profile Patterns of Inflammatory Processes
Authors: Sheen Kisung , Myung Seokho , Lee Dong-Min , Yu Sanghyeon , Choi Yueun , Kim Taeyoon , Kim Jihan , Ji Sang-Gu , Kim Myung-Seo , Kim Wonnam , Lee Yoonsung , Kim Man S. , Park Yeon-Cheol
Published: April 2024

The LPS-induced inflammation model is widely used for studying inflammatory processes due to its cost-effectiveness, reproducibility, and faithful representation of key hallmarks. While researchers often validate this model using clinical cytokine markers, a comprehensive understanding of gene regulatory mechanisms requires extending investigation beyond these hallmarks. Our study leveraged multiple whole-blood bulk RNA-seq datasets to rigorously compare the transcriptional profiles of the well-established LPS-induced inflammation model with those of several human diseases characterized by systemic inflammation. Beyond conventional inflammation-associated systems, we explored additional systems indirectly associated with inflammatory responses (i.e., ISR, RAAS, and UPR) using a customized core inflammatory gene list. Our cross-condition-validation approach spanned four distinct conditions: systemic lupus erythematosus (SLE) patients, dengue infection, candidemia infection, and staphylococcus aureus exposure. This analysis approach, utilizing the core gene list aimed to assess the model’s suitability for understanding the gene regulatory mechanisms underlying inflammatory processes triggered by diverse factors. Our analysis resulted in elevated expressions of innate immune-associated genes, coinciding with suppressed expressions of adaptive immune-associated genes. Also, upregulation of genes associated with cellular stresses and mitochondrial innate immune responses underscored oxidative stress as a central driver of the corresponding inflammatory processes in both the LPS-induced and other inflammatory contexts.
Short-Chain Fatty Acids and Human Health: From Metabolic Pathways to Current Therapeutic Implications
Authors: Facchin Sonia , Bertin Luisa , Bonazzi Erica , Lorenzon Greta , De Barba Caterina , Barberio Brigida , Zingone Fabiana , Maniero Daria , Scarpa Marco , Ruffolo Cesare , Angriman Imerio , Savarino Edoardo Vincenzo
Published: April 2024

The gastrointestinal tract is home to trillions of diverse microorganisms collectively known as the gut microbiota, which play a pivotal role in breaking down undigested foods, such as dietary fibers. Through the fermentation of these food components, short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are produced, offering numerous health benefits to the host. The production and absorption of these SCFAs occur through various mechanisms within the human intestine, contingent upon the types of dietary fibers reaching the gut and the specific microorganisms engaged in fermentation. Medical literature extensively documents the supplementation of SCFAs, particularly butyrate, in the treatment of gastrointestinal, metabolic, cardiovascular, and gut-brain-related disorders. This review seeks to provide an overview of the dynamics involved in the production and absorption of acetate, propionate, and butyrate within the human gut. Additionally, it will focus on the pivotal roles these SCFAs play in promoting gastrointestinal and metabolic health, as well as their current therapeutic implications.
Tribological Behavior of GTL Base Oil Improved by Ni-Fe Layered Double Hydroxide Nanosheets
Authors: Xiang Shuo , Zhi Xinghao , Bao Hebin , He Yan , Zhang Qinhui , Lin Shigang , Hu Bo , Wang Senao , Lu Peng , Yang Xin , Tian Qiang , Du Xin
Published: April 2024

The layered double hydroxide (LDH) has been practically applied in the field of tribology and materials science due to its unique physicochemical properties, weak bonding, flexible structural composition, and adjustable interlayer space. In this work, a series of ultrathin and flexible composition of Ni-Fe LDH samples were prepared via a cost-effective room-temperature co-precipitation process. Then, they were mechanically dispersed into GTL base oil and their lubricating performance were tested by a four-ball tribometer. It is found that the variation of Ni-Fe ratio of Ni-Fe LDH has a great influence on the improvement of lubricating performance of GTL base oil. At the same concentration (0.3 mg/mL), the Ni-Fe LDH with Ni/Fe ratio of 6 was demonstrated to exhibit the best lubricating performance and the AFC, WSD, the wear volume, surface roughness and average wear scar depth decreased 51.3%, 30.8%, 78.4%, 6.7% and 50.0%, respectively. SEM-EDS and X-ray photoelectron spectra illustrated that the tribo-chemical film consisting of iron oxides and NiO with better mechanical properties formed and slowly replaced the physical film, which resists scuffing and protect solid surface from severe collisions.
Fabrication of High Thermal Conductivity Aluminum Nitride Ceramics via Digital Light Processing 3D Printing
Authors: Tang Yuxin , Xue Zhenhai , Zhou Guohong , Hu Song
Published: April 2024

The sintering of high-performance ceramics with complex shapes at low temperatures has a significant impact on the future application of ceramics. A joint process of digital light processing (DLP) 3D printing technology and a nitrogen-gas pressure-assisted sintering method were proposed to fabricate AlN ceramics in the present work. Printing parameters, including exposure energy and time, were optimized for the shaping of green bodies. The effects of sintering temperature, as well as nitrogen pressure, on the microstructure, density, and thermal conductivity of AlN ceramics were systematically discussed. A high thermal conductivity of 168 W·m−1·K−1 was achieved by sintering and holding at a significantly reduced temperature of 1720 °C with the assistance of a 0.6 MPa nitrogen-gas pressure. Further, a large-sized AlN ceramic plate and a heat sink with an internal mini-channel structure were designed and successfully fabricated by using the optimized printing and sintering parameters proposed in this study. The heat transfer performance of the ceramic heat sink was evaluated by infrared thermal imaging, showing excellent cooling abilities, which provides new opportunities for the development of ceramic heat dissipation modules with complex geometries and superior thermal management properties.
Study on Pyrolysis Characteristics of Phosphate Tailings under H2O Atmosphere
Authors: Yang Yanping , Zhang Yu , Nie Dengpan , Sun Chenxin , Cao Jianxin
Published: April 2024

The pyrolysis separation of calcium and magnesium from phosphate tailings is an important process due to its high-value resource utilization. In this paper, aiming to address the problems of high energy consumption, a slow decomposition rate and the low activity of decomposition products in the high-temperature pyrolysis of phosphate tailings, the medium-temperature pyrolysis of phosphate tailings under a H2O atmosphere was carried out, and the phase reconstruction and activation of pyrolysis process were discussed. The results showed that compared with N2, air and CO2 atmospheres, the pyrolysis process of phosphate tailings in a H2O atmosphere was changed from two stages to one stage, the starting decomposition temperature was reduced to 500 °C and the decomposition time was shortened to 30 min. The order of the influence of each factor on the pyrolysis of phosphate tailings was temperature > H2O pressure > holding time. Under the optimized pyrolysis conditions, the yield of CaMg(CO3)2 decomposition of phosphate tailings into MgO and CaO was 97.3% and 98.1%, respectively, and the reactivity of MgO was 31.6%. The distribution of Ca and Mg elements in the phosphate tailings after pyrolysis showed a negative correlation, and both of them no longer formed associated compounds; Ca mainly existed in the form of Ca(OH)2, Ca5(PO4)3F, CaSiO3 and CaF2, and Mg mainly existed in the form of MgO, MgF2 and Mg(OH)2.
Thermal Stability, Durability, and Service Life Estimation of Woven Flax-Carbon Hybrid Polyamide Biocomposites
Authors: Bahrami Mohsen , Abenojar Juana , Aparicio Gladis M. , Martínez Miguel Angel
Published: April 2024

Woven flax-carbon hybrid polyamide biocomposites offer a blend of carbon fibers’ mechanical strength and flax’s environmental advantages, potentially developing material applications. This study investigated their thermal behavior, degradation kinetics, and durability to water uptake and relative humidity exposure and compared them with pure flax and carbon composites with the same matrix. The hybrid composite exhibited intermediate water/moisture absorption levels between pure flax and carbon composites, with 7.2% water absorption and 3.5% moisture absorption. It also displayed comparable thermal degradation resistance to the carbon composite, effectively maintaining its weight up to 300 °C. Further analysis revealed that the hybrid composite exhibited a decomposition energy of 268 kJ/mol, slightly lower than the carbon composite’s value of 288.5 kJ/mol, indicating similar thermal stability. Isothermal lifetime estimation, employing the activation energy (Ed) and degree of conversion facilitated by the Model Free Kinetics method, indicated a 41% higher service life of the hybrid laminate at room temperature compared to the carbon laminate. These insights are crucial for understanding the industrial applications of these materials without compromising durability.
Study on the Mechanical Properties of a Carbon-Fiber/Glass-Fiber Hybrid Foam Sandwich Structure
Authors: Cai Yingqiang , Wang Xiaolong , Ouyang Fenglin , Chen Qinglin , Zhu Zhaoyi , Fan Kuan , Ding Fan
Published: April 2024

Considering the different structural strength requirements of different parts of fiberglass yachts, carbon fiber/glass fiber hybrid reinforcement can be applied to the skins of sandwich panels in special areas. This paper designs and prepares 12 foam sandwich panel samples composed of pure carbon fiber, a carbon fiber/glass fiber hybrid, pure glass fiber skin, and PVC and SAN foam sandwich, with reference to the layup structure of the outer panel of a fiberglass yacht. Through a comparative analysis of low-speed impact experiments, edge compression experiments, and short beam three-point bending experiments, we seek the optimal carbon fiber/glass fiber hybrid layup design scheme for local structures to guide production. The results show that a reasonable hybrid carbon fiber layup in fiberglass skin can effectively reduce the low-speed impact damage of the sandwich structure, reduce edge compression damage, and improve the bending and compression resistance of sandwich structure. The impact resistance, compression resistance, and shear resistance of the SAN sandwich structure are stronger than the PVC sandwich structure. The carbon fiber/glass fiber hybrid SAN foam sandwich structure can be used for the local structural reinforcement of special parts such as the bow, side, and main deck of fiberglass yachts.
Assessment of Potential Use of a Composite Based on Polyester Textile Waste as Packing Elements of a Trickle Bed Bioreactor
Authors: Gloc Martyna , Paździor Katarzyna , Kudzin Marcin , Mrozińska Zdzisława , Kucińska-Król Iwona , Żyłła Renata
Published: April 2024

Biological wastewater treatment using trickle bed reactors is a commonly known and used solution. One of the key elements of the proper operation of the trickle bed bioreactor is the appropriate selection of biofilm support elements. The respective properties of the bioreactor packing media used can influence, among other things, the efficiency of the treatment process. In this study, the possibility of polyester waste material usage for the preparation of the biofilm support elements was tested. The following properties were checked: adsorption capacity, swelling, surface morphology, microbicidal properties, as well as the possibility of their use in biological wastewater treatment. The tested elements did not adsorb copper nor showed microbicidal properties for bacterial strains Escherichia coli and Staphylococcus aureus as well as fungal strains Aspergillus niger and Chaetomium globosum. The hydrophilic and rough nature of the element surface was found to provide a friendly support for biofilm formation. The durability of the elements before and after their application in the biological treatment process was confirmed by performing tests such as compressive strength, FTIR analysis, hardness analysis and specific surface area measurement. The research confirmed the applicability of the packing elements based on polyester textile waste to the treatment of textile wastewater. The treatment efficiency of the model wastewater stream was above 90%, while in the case of a stream containing 60% actual industrial wastewater it was above 80%. The proposed solution enables the simultaneous management of textile waste and wastewater treatment, which is consistent with the principles of a circular economy. The selected waste raw material is a cheap and easily available material, and the use of the developed packing elements will reduce the amount of polyester materials ending up in landfills.
Fabrication of Ciprofloxacin-Immobilized Calcium Phosphate Particles for Dental Drug Delivery
Authors: Pal Aniruddha , Oyane Ayako , Inose Tomoya , Nakamura Maki , Nishida Erika , Miyaji Hirofumi
Published: April 2024

Calcium phosphate (CaP) particles immobilizing antibacterial agents have the potential to be used as dental disinfectants. In this study, we fabricated CaP particles with immobilized ciprofloxacin (CF), a commonly prescribed antibacterial agent, via a coprecipitation process using a supersaturated CaP solution. As the aging time in the coprecipitation process increased from 2 to 24 h, the CaP phase in the resulting particles transformed from amorphous to low-crystalline hydroxyapatite, and their Ca/P elemental ratio, yield, and CF content increased. Despite the higher CF content, the particles aged for 24 h displayed a slower release of CF in a physiological salt solution, most likely owing to their crystallized matrix (less soluble hydroxyapatite), than those aged for 2 h, whose matrix was amorphous CaP. Both particles exhibited antibacterial and antibiofilm activities along with an acid-neutralizing effect against the major oral bacteria, Streptococcus mutans, Porphyromonas gingivalis, and Actinomyces naeslundii, in a dose-dependent manner, although their dose–response relationship was slightly different. The aging time in the coprecipitation process was identified as a governing factor affecting the physicochemical properties of the resulting CF-immobilized CaP particles and their functionality as a dental disinfectant.
A New Double-Step Process of Shortening Fibers without Change in Molding Equipment Followed by Electron Beam to Strengthen Short Glass Fiber Reinforced Polyester BMC
Authors: Faudree Michael C. , Nishi Yoshitake
Published: April 2024

It is vital to maximize the safety of outdoor constructions, airplanes, and space vehicles by protecting against the impact of airborne debris from increasing winds due to climate change, or from bird strikes or micrometeoroids. In a widely-used compression-molded short glass fiber polyester bulk-molded compound (SGFRP-BMC) with 55% wt. CaCO3 filler, the center of the mother panel has lower impact strength than the outer sections with solidification texture angles and short glass fiber (SGF) orientations being random from 0 to 90 degrees. Therefore, a new double-step process of: (1) reducing commercial fiber length without change in molding equipment; followed by a (2) 0.86 MGy dose of homogeneous low-voltage electron beam irradiation (HLEBI) to both sides of the finished samples requiring no chemicals or additives, which is shown to increase the Charpy impact value (auc) about 50% from 6.26 to 9.59 kJm−2 at median-accumulative probability of fracture, Pf = 0.500. Shortening the SGFs results in higher fiber spacing density, Sf, as the thermal compressive stress site proliferation by action of the CTE difference between the matrix and SGF while the composite cools and shrinks. To boost impact strength further, HLEBI provides additional nano-compressive stresses by generating dangling bonds (DBs) creating repulsive forces while increasing SGF/matrix adhesion. Increased internal cracking apparently occurs, raising the auc.
Utilizing Wheel Washing Machine Sludge as a Cement Substitute in Repair Mortar: An Experimental Investigation into Material Characteristics
Authors: Jang Changhwan , Abebe Tadesse Natoli
Published: April 2024

The construction industry strives for sustainable solutions to tackle environmental challenges and optimize resource use. One such focus area is the management of industrial byproducts and waste materials, including fugitive dust control through wheel washers. While wheel washers play a pivotal role in dust management, they generate a challenging byproduct known as wheel washer sludge (WWS). The disposal of WWS is complicated due to its composition and potential hazards. Recent research explores reusing WWS in construction materials, particularly in repair mortar, aiming for sustainability and circular economy principles. This study investigates the incorporation of WWS into repair mortar formulations, evaluating mechanical properties, durability, and environmental implications. Results show that WWS enhances workability but prolongs setting time. Mechanical strength tests reveal improvements with WWS addition, especially when pretreated. Water absorption rates decrease with pretreated WWS, indicating enhanced durability. Chemical attack tests demonstrate resistance to carbonation and chloride penetration, especially with modified WWS. Freeze–thaw tests reveal improved resistance with WWS addition, particularly modified. Microstructure analysis confirms hydration products and denser matrices with WWS inclusion. Environmental hazard analysis shows WWS contains no harmful heavy metals, indicating its suitability for use in repairs. Overall, this study highlights the technical feasibility and environmental benefits of incorporating WWS into repair mortar, contributing to sustainable construction practices.
Development of New Composite Materials by Modifying the Surface of Porous Hydroxyapatite Using Cucurbit[n]urils
Authors: Burkhanbayeva Tolkynay , Ukhov Arthur , Fedorishin Dmitry , Gubankov Alexander , Kurzina Irina , Bakibaev Abdigali , Yerkassov Rakhmetulla , Mashan Togzhan , Suyundikova Faiziya , Nurmukhanbetova Nurgul , Khamitova Aina
Published: April 2024

This study represents an advancement in the field of composite material engineering, focusing on the synthesis of composite materials derived from porous hydroxyapatite via surface modification employing cucurbit[n]urils, which are highly promising macrocyclic compounds. The surface modification procedure entailed the application of cucurbit[n]urils in an aqueous medium onto the hydroxyapatite surface. A comprehensive characterization of the resulting materials was undertaken, employing analytical techniques including infrared (IR) spectroscopy and scanning electron microscopy (SEM). Subsequently, the materials were subjected to rigorous evaluation for their hemolytic effect, anti-inflammatory properties, and cytotoxicity. Remarkably, the findings revealed a notable absence of typical hemolytic effects in materials incorporating surface-bound cucurbit[n]urils. This observation underscores the potential of these modified materials as biocompatible alternatives. Notably, this discovery presents a promising avenue for the fabrication of resilient and efficient biocomposites, offering a viable alternative to conventional approaches. Furthermore, these findings hint at the prospect of employing supramolecular strategies involving encapsulated cucurbit[n]urils in analogous processes. This suggests a novel direction for further research, potentially unlocking new frontiers in material engineering through the exploitation of supramolecular interactions.
Design and In Vitro Activity of Furcellaran/Chitosan Multilayer Microcapsules for the Delivery of Glutathione and Empty Model Multilayer Microcapsules Based on Polysaccharides
Authors: Drozdowska Mariola , Piasna-Słupecka Ewelina , Such Aleksandra , Dziadek Kinga , Krzyściak Paweł , Kruk Tomasz , Duraczyńska Dorota , Morawska-Tota Małgorzata , Jamróz Ewelina
Published: April 2024

In this study, multilayer microcapsules (two-layer and four-layer) based on furcellaran (FUR) and chitosan (CHIT) were produced, enclosing a tripeptide with an antioxidant effect—glutathione—in different concentrations. In addition, for the first time, an empty, four-layer microcapsule based on CHIT and FUR (ECAPS) was obtained, which can be used to contain sensitive, active substances of a hydrophobic nature. Layering was monitored using zeta potential, and the presence of the resulting capsules was confirmed by SEM imaging. In the current study, we also investigated whether the studied capsules had any effect on the Hep G2 cancer cell line. An attempt was also made to identify the possible molecular mechanism(s) by which the examined capsules suppressed the growth of Hep G2 cells. In this report, we demonstrate that the capsules suppressed the growth of cancer cells. This mechanism was linked to the modulation of the AKT/PI3K signaling pathway and the induction of the G2/M arrest cell cycle. Furthermore, the results indicate that the tested multilayer microcapsules induced cell death through an apoptotic pathway.