bluuebunny/crossref_metadata_2025 huggingface dataset:
Epigenetically Downregulated Breast Cancer Gene 2 through Acetyltransferase Lysine Acetyltransferase 2B Increases the Sensitivity of Colorectal Cancer to Olaparib
Authors: Chen Siche , Allgayer Heike
Published: November 2023

Olaparib suppresses DNA damage repair by inhibiting the poly ADP ribose polymerase (PARP), especially in cancers with BRCA1/2 mutations or the BRCA-ness phenotype. However, the first trials showed that some patients with defective DNA damage repair are still resistant to olaparib. The recovery of the wildtype BRCA is a prominent mechanism of PARP inhibitor (PARPi) resistance in BRCA-deficient tumors, but additional molecular features of olaparib resistance remain poorly understood. The objective of our study was to find molecular parameters that contribute to olaparib response or resistance in CRC. We report that histone acetyltransferase KAT2B decreases BRCA2 expression by reducing the acetylation of the 27th amino acid in histone H3 (H3K27) at the promoter of the BRCA2 gene in colorectal cancer (CRC). This increases the sensitivity of CRC cells toward olaparib treatment. The H3K27ac binding domain of BRCA2 may be required for its transcription. Low endogenous KAT2B expression, which we identify in a subset of cultured BRCA2-expressing CRC cells, leads to an accumulation of γH2AX (more DNA damage), resulting in low PARPi resistance in BRCA-expressing cells. Our results reveal KAT2B and histone acetylation as regulators of BRCA2 expression and PARPi responses in BRCA2-expressing CRC cells, providing further insights into molecular prerequisites for targeting BRCA-functional tumors.
Treatment and Outcomes of Radiation-Induced Soft Tissue Sarcomas of the Extremities and Trunk—A Systematic Review of the Literature
Authors: Inchaustegui Maria L. , Kon-Liao Kelly , Ruiz-Arellanos Kim , Silva George Aquilino E. , Gonzalez Marcos R. , Pretell-Mazzini Juan
Published: November 2023

Introduction: Radiation-induced soft tissue sarcomas (RISs) are rare secondary malignancies with a dire prognosis. The literature on the management of these tumors remains scarce due to their low incidence. Our systematic review sought to assess the treatment alternatives and outcomes of patients with RIS. Methods: A systematic review was conducted following the PRISMA guidelines. Our study was registered in PROSPERO (ID: CRD42023438415). Quality assessment was performed using the STROBE checklist. Weighted means for both continuous and categorical values were calculated. Results: Twenty-one studies comprising 1371 patients with RIS were included. The mean latency period from radiation to RIS diagnosis was 14 years, and the mean radiation dose delivered to the primary malignancy was 29.2 Gy. The most common histological type was undifferentiated pleomorphic sarcoma (42.2%), and 64% of all tumors were high-grade. The trunk was the most common location (59%), followed by extremities (21%) and pelvis (11%). Surgery was performed in 68% of patients and, among those with an appendicular tumor, the majority (74%) underwent limb-salvage surgery. Negative margins were attained in 58% of patients. Chemotherapy and radiotherapy were administered in 29% and 15% of patients, respectively. The mean 5-year overall survival was 45%, and the local recurrence and metastasis rates were 39% and 27%, respectively. Conclusions: In our study, the most common treatment was surgical resection, with RT and chemotherapy being administered in less than one third of patients. Patients with RIS exhibited poor oncologic outcomes. Future studies should compare RIS with de novo STS while controlling for confounders.
Cancer Cachexia: New Insights and Future Directions
Authors: Mariean Claudia Raluca , Tiucă Oana Mirela , Mariean Alexandru , Cotoi Ovidiu Simion
Published: November 2023

Cancer remains a major health problem and is associated with cachexia in up to 80% of cases, leading to decreased survival and quality of life. Cachexia involves complex metabolic disturbances in both protein and energy balance, muscle wasting phenomena, weight loss, systemic inflammation, overall decreased performance status, and tolerability to treatment. The clinical impact of cancer cachexia is very complex, with early detection of cachectic patients and identification of predictive biomarkers being two key factors for improving survival. Thus, a better understanding of the complexity of cancer cachexia phenomena and its main pathophysiological mechanism is much needed. Our review highlights the most important information about cancer cachexia, aiming to disseminate updated research findings about this highly deadly condition.
Association between Immune Checkpoint Inhibitor Treatment Outcomes and Body Composition Factors in Metastatic Renal Cell Carcinoma Patients
Authors: Takei Kohei , Kijima Toshiki , Okubo Naoya , Kurashina Ryo , Kokubun Hidetoshi , Uematsu Toshitaka , Betsunoh Hironori , Yashi Masahiro , Kamai Takao
Published: November 2023

Introduction: Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of metastatic renal cell carcinoma (mRCC); however, validating body composition-related biomarkers for their efficacy remains incomplete. We evaluated the association between body composition-related markers and the prognosis of patients with mRCC who received ICI-based first-line therapies. Patients and Methods: We retrospectively investigated 60 patients with mRCC who underwent ICI-based therapy as their first-line treatment between 2019 and 2023. Body composition variables, including skeletal muscle, subcutaneous fat, and visceral fat indices, were calculated using baseline computed tomography scans. Sarcopenia was defined according to sex-specific cut-off values of the skeletal mass index. The associations between body composition indices and objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were evaluated. Results: Patients with sarcopenia had lower ORR and DCR than those without sarcopenia (33.3% vs. 61.1%, p = 0.0436 and 52.4% vs. 94.4%, p = 0.0024, respectively). Patients with sarcopenia had a significantly shorter median PFS (14 months vs. not reached, p = 0.0020) and OS (21 months vs. not reached, p = 0.0023) than patients without sarcopenia did. Sarcopenia was a significant predictor of PFS (hazard ratio [HR], 4.31; 95% confidence interval [CI], 1.65–14.8; p = 0.0018) and OS (HR, 5.44; 95% CI, 1.83–23.4; p = 0.0013) along with poor IMDC risk. No association was found between the subcutaneous, visceral, and total fat indices and the therapeutic effect of ICI-based therapy. Conclusions: Sarcopenia was associated with a lower response and shorter survival rates in patients with mRCC who received first-line ICI-based therapy.
Treatment Sequencing and Outcome of Chronic Lymphocytic Leukemia Patients Treated at Fondazione Policlinico Universitario Agostino Gemelli IRCCS: A Thirty-Year Single-Center Experience
Authors: Innocenti Idanna , Fresa Alberto , Tomasso Annamaria , Tarnani Michela , De Padua Laura , Benintende Giulia , Pasquale Raffaella , Galli Eugenio , Morelli Francesca , Giannarelli Diana , Autore Francesco , Laurenti Luca
Published: November 2023

Background: This monocentric retrospective study describes the treatment patterns and outcomes of chronic lymphocytic leukemia (CLL) patients. Methods: Adult CLL patients treated between 1992 and 2022 were included. The time to next treatment (TTNT) was defined as the time from the treatment’s start to the start of a subsequent therapy or death. The time to next treatment failure or death (TTNTF) was defined as the time from treatment discontinuation to the discontinuation of a subsequent therapy or death. Results: Of 637 registered patients, 318 (49.9%) received treatment. We evaluated 157 cBTKi-exposed, 34 BCL2i-exposed cBTKi-naïve, and 26 double-exposed patients. The five-year TTNT values in the cBTKi-exposed patients were 80% (median NR), 40% (median 40 months), and 21% (median 24 months) months in the first line (1L), second line (2L), and beyond the second line (>2L), respectively (p < 0.0001). The five-year TTNT values in the BCL2i-exposed patients were 83% (median NR), 72% (median NR), 12% (median 28 months) in the 1L, 2L, and >2L, respectively (p = 0.185). The median TTNTF was 9 months (range 1–87) after cBTKi and 17 months (range 8–49) after both a cBTKi and BCL2i. Conclusions: This study suggests that, in CLL patients, the earlier we used targeted therapies, the better was the outcome obtained. Nonetheless, the poor outcomes in the advanced lines of therapy highlight the need for more effective treatments.
Development of MDS in Pediatric Patients with GATA2 Deficiency: Increased Histone Trimethylation and Deregulated Apoptosis as Potential Drivers of Transformation
Authors: Schreiber Franziska , Piontek Guido , Schneider-Kimoto Yuki , Schwarz-Furlan Stephan , De Vito Rita , Locatelli Franco , Gengler Carole , Yoshimi Ayami , Jung Andreas , Klauschen Frederick , Niemeyer Charlotte M. , Erlacher Miriam , Rudelius Martina
Published: November 2023

GATA2 deficiency is a heterogeneous, multisystem disorder associated with a high risk of developing myelodysplastic syndrome (MDS) and the progression to acute myeloid leukemia. The mechanisms underlying malignant transformation in GATA2 deficiency remain poorly understood, necessitating predictive markers to assess an individual’s risk of progression and guide therapeutic decisions. In this study, we performed a systematic analysis of bone marrow biopsies from 57 pediatric MDS patients. Focusing on hematopoiesis and the hematopoietic niche, including its microenvironment, we used multiplex immunofluorescence combined with multispectral imaging, gene expression profiling, and multiplex RNA in situ hybridization. Patients with a GATA2 deficiency exhibited a dysregulated GATA2 transcriptional network. Disease progression (GATA2-EB, n = 6) was associated with increased GATA2 mRNA levels, restored expression of the GATA2 target EZH2, and increased H3K27me3. GATA2-EB was further characterized by the high expression of the anti-apoptotic protein BCL2, a feature absent in children with a GATA2 deficiency and refractory cytopenia of childhood (GATA2-RCC, n = 24) or other pediatric MDS subgroups (RCC, n = 17; MDS-EB, n = 10). The multispectral imaging analysis of additional BCL2 family members revealed significantly elevated Mediators of Apoptosis Combinatorial (MAC) scores in GATA2-EB patients. Taken together, our findings highlight the potential drivers of disease progression in GATA2 deficiency, particularly increased histone trimethylation and dysregulated apoptosis. Furthermore, upregulated BCL2 and EZH2 and increased MAC scores provide a strong rationale for the use of venetoclax and azacitidine in therapeutic regimens for GATA2-EB.
Cervical Cancer Stages, Human Papillomavirus Integration, and Malignant Genetic Mutations: Integrative Analysis of Datasets from Four Different Cohorts
Authors: Mohammed Foziya Ahmed , Tune Kula Kekeba , Jett Marti , Muhie Seid
Published: November 2023

Cervical cancer represents a significant global health concern, stemming from persistent infections with high-risk types of human papillomavirus (HPV). The understanding of cervical cancer’s clinical correlates, risk factors, molecular mechanisms, stages, and associated genetic mutations is important for early detection and improved treatment strategies. Through integrated analysis of clinical and molecular datasets, this study aims to identify key factors that are overlapping and distinct across four cohorts of different races and regions. Here, datasets from four distinct cohorts of patients from Uganda (N = 212), the United States of America (USA) (N = 228), China (N = 106), and Venezuela (N = 858) were examined to comprehensively explore the relationships between cervical cancer stages, HPV types (clades), productive HPV integration, and malignant genetic mutations. Cohort-specific findings included the occurrence frequencies of cervical cancer stages and grades. The majority of patients from the USA and China were diagnosed with stages I and II, while those from Uganda were diagnosed with stages II and III, reflecting levels of awareness and the availability of HPV vaccines and screening services. Conversely, cervical cancer and its stages were positively correlated with HPV types (clades), HPV integration, and risk-factor habits across the cohorts. Our findings indicate that the more common squamous cervical cancer can be potentially due to productive HPV16 (clade 9) integration. At the molecular level, pathways related to HPV infection, cancer-related conditions, and viral carcinogenesis were among the most significant pathways associated with mutated genes in cervical cancer (across cohorts). These findings collectively corroborate the prominent role of HPV infection and integration leading to genetic mutation and hence to the development of cervical cancer and its stages across patients of distinct races and regions.
Identifying Predictive Biomarkers for Head and Neck Squamous Cell Carcinoma Response
Authors: Becker Anne-Sophie , Kluge Cornelius , Schofeld Carsten , Zimpfer Annette , Schneider Björn , Strüder Daniel , Redwanz Caterina , Ribbat-Idel Julika , Idel Christian , Maletzki Claudia
Published: November 2023

The 5-year survival rate for head and neck squamous cell carcinoma (HNSCC) is approximately 65%. In addition to radio-chemotherapy, immunotherapy is an approach in the treatment of advanced HNSCC. A better understanding of the immune context would allow personalized treatment by identifying patients who are best suited for different treatment options. In our discovery cohort, we evaluated the expression profiles of CMTM6, PD-L1, CTLA-4, and FOXP3 in 177 HNSCCs from Caucasian patients of all tumor stages and different treatment regimens, correlating marker expression in tumor and immune cells with outcomes. Patients with CMTM6high-expressing tumors had a longer overall survival regardless of treatment. This prognostic benefit of CMTM6 in HNSCC was validated in an independent cohort. Focusing on the in the discovery cohort (n = 177), a good predictive effect of CMTM6high expression was seen in patients receiving radiotherapy (p = 0.07; log rank), but not in others. CMTM6 correlated with PD-L1, CTLA-4 and FOXP3 positivity, with patients possessing CMTM6high/FOXP3high tumors showing the longest survival regardless of treatment. In chemotherapy-treated patients, PD-L1 positivity was associated with longer progression-free survival (p < 0.05). In the 27 patients who received immunotherapy, gene expression analysis revealed lower levels of CTLA-4 and FOXP3 with either partial or complete response to this treatment, while no effect was observed for CMTM6 or PD-L1. The combination of these immunomodulatory markers seems to be an interesting prognostic and predictive signature for HNSCC patients with the ability to optimize individualized treatments.
Reflectance Confocal Microscopy and Dermoscopy of Facial Pigmented and Non-Pigmented Actinic Keratosis Features before and after Photodynamic Therapy Treatment
Authors: Mazur Ewelina , Kwiatkowska Dominika , Reich Adam
Published: November 2023

Actinic keratosis (AK), due to its widespread prevalence, as well as the possibility of progression to an invasive form of squamous cell carcinoma, requires treatment regardless of the clinical stage. New imaging techniques, such as in vivo reflectance confocal microscopy (RCM), significantly increase the accuracy of diagnosis and allow noninvasive evaluation of the therapeutic efficacy of the ongoing treatment. Our objective was to evaluate the prevalence of specific (video)dermoscopy and RCM features of pigmented and classical subtypes of AK before and after photodynamic therapy (PDT) treatment. We included patients with facial grade II AKs (25 pigmented, 275 non-pigmented) were included in the study. Skin lesions were evaluated by (video)dermoscopy and RCM at the baseline and three months after PDT. In classic AK, the most frequent dermoscopic findings were fine wavy vessels (96%), scale (92%), microerosions (48%), and “strawberry” pattern (36%), while pigmented AK was characterized mostly by “rhomboidal pattern” (80%), scale (60%), white globules (48%), “jelly sign”, and superficial pigmentation (40%). RCM’s most characteristic classic AK findings were abnormal honeycomb pattern in the spinous layer, epidermal inflammatory infiltrate, and solar elastosis that were present in 96% of lesions. Pigmented AKs presented mostly with dark central areas of parakeratosis (72%), mottled pigmentation (72%), dermal inflammatory infiltrate (64%), solar elastosis (60%), and abnormal honeycomb pattern in the spinous layer (56%). Dermoscopically, PDT resulted in complete disappearance of the “rhomboidal pattern” in both classical and pigmented AKs, “starburst pattern” and “jelly sign” in classical AKs, and inner gray halo, “rosette sign” and central crust in pigmented AKs. Three months after one PDT session, RCM evaluation showed mostly solar elastosis in both classical and pigmented AK subtypes, epidermal inflammatory infiltrate in classical AKs, and dermal inflammatory infiltrate in pigmented AKs. New noninvasive imaging techniques such as RCM and (video)dermoscopy can help practitioners better visualize the efficacy of the ongoing PDT treatment in either classical or pigmented AK subtypes.
Overview of Risk Factors for Esophageal Squamous Cell Carcinoma in China
Authors: Conway Erica , Wu Haisheng , Tian Linwei
Published: November 2023

(1) Background: China has the highest esophageal squamous cell carcinoma (ESCC) incidence areas in the world, with some areas of incidence over 100 per 100,000. Despite extensive public health efforts, its etiology is still poorly understood. This study aims to review and summarize past research into potential etiologic factors for ESCC in China. (2) Methods: Relevant observational and intervention studies were systematically extracted from four databases using key terms, reviewed using Rayyan software, and summarized into Excel tables. (3) Results: Among the 207 studies included in this review, 129 studies were focused on genetic etiologic factors, followed by 22 studies focused on dietary-related factors, 19 studies focused on HPV-related factors, and 37 studies focused on other factors. (4) Conclusions: ESCC in China involves a variety of factors including genetic variations, gene–environment interactions, dietary factors like alcohol, tobacco use, pickled vegetables, and salted meat, dietary behavior such as hot food/drink consumption, infections like HPV, poor oral health, gastric atrophy, and socioeconomic factors. Public health measures should prioritize genetic screening for relevant polymorphisms, conduct comprehensive investigations into environmental, dietary, and HPV influences, enhance oral health education, and consider socioeconomic factors overall as integral strategies to reduce ESCC in high-risk areas of China.
Recent Advances in Surface Plasmon Resonance (SPR) Technology for Detecting Ovarian Cancer Biomarkers
Authors: Kumar Vikneswary Ravi , Kampan Nirmala Chandralega , Abd Aziz Nor Haslinda , Teik Chew Kah , Shafiee Mohamad Nasir , Menon P. Susthitha
Published: November 2023

Epithelial Ovarian Cancer (EOC) is a leading cause of cancer-related deaths among women, mainly due to a lack of early detection and screening methods. Advanced immunoassay techniques, such as Luminex and proximity extension assay (PEA) technology, show promise in improving EOC detection by utilizing highly sensitive and specific multiplex panels to detect multiple combinations of biomarkers. However, these advanced immunoassay techniques have certain limitations, especially in validating the performance characteristics such as specificity, sensitivity, limit of detection (LOD), and dynamic range for each EOC biomarker within the panel. Implementing multiplexing in point-of-care (POC) biosensors can enhance EOC biomarker detection, with Surface Plasmon Resonance (SPR) being a versatile option among optical biosensors. There is no study on multiplex SPR biosensors specifically tailored for diagnosing EOC. Recent studies have shown promising results in the single detection of EOC biomarkers using SPR, with LOD for cancer antigen 125 (CA125) at 0.01 U/mL−1 and human epididymis protein 4 (HE4) at 1pM. This study proposes a potential roadmap for scientists and engineers in academia and industry to develop a cost effective yet highly efficient SPR biosensor platform for detecting EOC.
Satureja bachtiarica Induces Cancer Cell Death in Breast and Glioblastoma Cancer in 2D/3D Models and Suppresses Breast Cancer Stem Cells
Authors: Zavareh Vajihe , Gharibi Shima , Hosseini Rizi Mahnaz , Nekookar Abdolhossein , Mirhendi Hossein , Rahimmalek Mehdi , Szumny Antoni
Published: November 2023

Overcoming drug resistance and specifically targeting cancer stem cells (CSCs) are critical challenges in improving cancer therapy. Nowadays, the use of novel and native medicinal plants can provide new sources for further investigations for this purpose. The aim of this study was to assess the potential of S. bachtiarica, an endemic plant with diverse medicinal applications, in suppressing and targeting cancer and cancer stem cells in glioblastoma and breast cancer. The effect of S. bachtiarica on viability, migration, invasion, and clonogenic potential of MDAMB-231 and U87-MG cells was assessed in both two- and three-dimensional cell culture models. Additionally, we evaluated its effects on the self-renewal capacity of mammospheres. The experimental outcomes indicated that S. bachtiarica decreased the viability and growth rate of cells and spheroids by inducing apoptosis and inhibited colony formation, migration, and invasion of cells and spheroids. Additionally, colony and sphere-forming ability, as well as the expression of genes associated with EMT and stemness were reduced in mammospheres treated with S. bachtiarica. In conclusion, this study provided valuable insights into the anti-cancer effects of S. bachtiarica, particularly in relation to breast CSCs. Therefore, S. bachtiarica may be a potential adjuvant for the treatment of cancer.
Sports Practice, Body Image Perception, and Factors Involved in Sporting Activity in Italian Schoolchildren
Authors: Zaccagni Luciana , Rosa Luca , Toselli Stefania , Gualdi-Russo Emanuela
Published: November 2023

Regular physical activity is generally deemed to positively affect health, but studies on children are scarce. Among the kinds of physical activity, sports practice is the most common and easiest to quantify and report by children. This cross-sectional study aimed to compare the two genders and evaluate the association between organized sports practice and body dissatisfaction in a sample of 214 Italian schoolchildren (55.6% males) aged 5 to 12. Body image perception and data on sports practice expectations and facilitators were collected in individual face-to-face interviews; weight and stature were directly measured. Girls tended to be sportier than boys (91.6% of girls vs. 86.3% of boys practiced sports), with an earlier start in sports (5.48 ± 1.47 vs. 5.72 ± 1.38 years) and a greater amount of weekly sports (3.41 ± 2.95 vs. 3.01 ± 2.11 h/week). In both genders, the ideal silhouette was more slender than the feel silhouette, and in girls more than in boys. According to the outcomes of multiple regression models, years of organized sports participation were a significant predictor of the weekly amount of sports in both genders, in addition to the feel weight status minus actual weight status inconsistency score, fun in sports, and parental support only in boys and teacher support only in girls. Children’s needs and interests and sports facilitators should be considered to promote an early active lifestyle.
Eye Movement Evidence for Simultaneous Cognitive Processing in Reading
Authors: Fella Argyro , Loizou Maria , Christoforou Christoforos , Papadopoulos Timothy C.
Published: November 2023

Measuring simultaneous processing, a reliable predictor of reading development and reading difficulties (RDs), has traditionally involved cognitive tasks that test reaction or response time, which only capture the efficiency at the output processing stage and neglect the internal stages of information processing. However, with eye-tracking methodology, we can reveal the underlying temporal and spatial processes involved in simultaneous processing and investigate whether these processes are equivalent across chronological or reading age groups. This study used eye-tracking to investigate the simultaneous processing abilities of 15 Grade 6 and 15 Grade 3 children with RDs and their chronological-age controls (15 in each Grade). The Grade 3 typical readers were used as reading-level (RL) controls for the Grade 6 RD group. Participants were required to listen to a question and then point to a picture among four competing illustrations demonstrating the spatial relationship raised in the question. Two eye movements (fixations and saccades) were recorded using the EyeLink 1000 Plus eye-tracking system. The results showed that the Grade 3 RD group produced more and longer fixations than their CA controls, indicating that the pattern of eye movements of young children with RD is typically deficient compared to that of their typically developing counterparts when processing verbal and spatial stimuli simultaneously. However, no differences were observed between the Grade 6 groups in eye movement measures. Notably, the Grade 6 RD group outperformed the RL-matched Grade 3 group, yielding significantly fewer and shorter fixations. The discussion centers on the role of the eye-tracking method as a reliable means of deciphering the simultaneous cognitive processing involved in learning.
Feasibility of Using the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY) as a Framework for Aquatic Activities: A Scoping Review
Authors: Hadar-Frumer Merav , Ten-Napel Huib , Yuste-Sánchez Maria José , Rodríguez-Costa Isabel
Published: November 2023

(1) Background: In recent years, reviewing studies of aquatic activities for children with developmental delays has been a complex task due to the multitude of indices and professional languages. (2) Aim: To determine if the ICF-CY framework can be used as the unifying language in AA studies of children with DD. (3) Methods: Part One—A systematic review of selected studies focusing on goals that were found to be positive. These goals were linked to the ICF-CY categories. Part Two—Review of all studies using the ICF-CY’s functioning components. (4) Results: Most of the positive goals were properly linked to ICF-CY and made it possible to review the 71 articles in a uniform language. (5) Conclusions: It is feasible to use the ICF framework as a universal structure and language.
Simulating the Effect of Depositing an 8YSZ Buffer Layer in P92/Al2O3 on the Thermal Cycles Endurance and Fracture Toughness of the System
Authors: Huang Kezhi , Liu Yu , Wang Weijing , Yu Qinghe , Mi Jing , Hao Lei , Liu Hao , Yuan Baolong , Xiao Wei , Chen Xiaotao , Dong Ziqiang , Wang Ping
Published: November 2023

The effect of depositing 8YSZ between serving as an intermediate layer of the P92/Al2O3 was analyzed via finite element analysis. The result shows that depositing an 8YSZ buffer coat beneath the Al2O3 will dramatically decrease the maximum principal stress in the coating system in thermal shock. The stress intensity factor, KI, and J-integral are also decreased which indicates the crack propagation resistance is improved. Inserting a 100 nm 8YSZ buffer layer could reduce the KI and J-integral by 2 orders of magnitude. Thus, cracks are less likely to initiate and propagate. Moreover, coating an 8YSZ layer between the P92/Al2O3 can significantly change the stress distribution pattern in the Al2O3 coating. The 8YSZ with a proper coefficient of thermal expansion between that of the Al2O3 and P92 and good deformability is an ideal buffer layer to improve the thermal cycle endurance and prolong the service life of the Al2O3 coating.
Effect of Alternating Magnetic Field on the Organization and Corrosion Resistance of 2205 Duplex Stainless Steel Narrow-Gap Laser-MIG Hybrid Weld Head
Authors: He Zhenxing , Zhao Yong , Fu Juan , Chen Fugang , Chen Guoqiang , Qin Yonghui
Published: November 2023

In this study, an alternating magnetic field is applied in the narrow-gap laser-MIG hybrid welding of 2205 duplex stainless steel with a thickness of 25 mm to achieve the purpose of balancing the ration of the two phases, refining the grains and improving the corrosion resistance. With the help of OM, EBSD, TEM, and other microstructural analysis methods, the organization evolution of a 2205 duplex stainless steel narrow-gap laser arc hybrid weld under the effect of alternating magnetic field is revealed. The corrosion resistance of the welded joints is investigated by electrochemical tests. The results show that the use of a 40 mT applied alternating magnetic field can not only effectively inhibit the generation of porosity and unfused defects in the weld, but also that the addition of an alternating magnetic field improves the ratio of austenite to ferrite in the weld, and the ratio of the two phases is increased from 0.657 without a magnetic field to 0.850. The weld grain preferential orientation is affected by the magnetic field, and the weld austenite grains are shifted from the Goss texture to the Copper texture. Under the electromagnetic stirring effect of the applied magnetic field, the average austenite grain size decreased from 4.15 μm to 3.82 μm, and the average ferrite grain size decreased from 4.99 μm to 4.08 μm. In addition, the effect of the alternating magnetic field increases the density of twins in the organization. Electrochemical test results show that the addition of an alternating magnetic field increases the corrosion potential by 75.2 mV and the pitting potential by 134.5 mV, which indicates that the corrosion resistance of the cover-welded specimens is improved by the effect of an alternating magnetic field. The improvement in corrosion resistance mainly depends on the austenite grain refinement and the increase in the austenite content.
Study on the Performance and Modification Mechanism of Polyphosphoric Acid (PPA)/Styrene–Butadiene–Styrene (SBS) Composite Modified Asphalt
Authors: Niu Xiangjie , Chen Yuanzhao , Li Zhenxia , Guo Tengteng , Wang Jing , Jin Lihui
Published: November 2023

In order to address the high preparation cost of styrene–butadiene–styrene block copolymer (SBS) modified asphalt, four kinds of polyphosphoric acid (PPA) content (0%, 0.5%, 0.75%, and 1% PPA by weight of the matrix asphalt) were selected to prepare composite modified asphalt with better high-temperature performance. The physical properties of composite modified asphalt were evaluated by conventional performance tests. The rheological properties of composite modified asphalt were evaluated by dynamic shear rheometer (DSR) test and bending beam rheometer (BBR) test. The synergistic modification mechanism of PPA and SBS was revealed by the Fourier transform infrared spectroscopy test. The results show that with the increase of PPA content, the penetration of PPA/SBS composite modified asphalt is reduced by 20.92%, 25.07% and 28.94%, respectively, compared with matrix asphalt, and the softening point is increased by 5.46%, 22.69% and 34.03%, respectively. In addition, PPA can improve the thermal oxidative aging resistance of asphalt. PPA can improve the shear resistance, high-temperature performance and temperature sensitivity of asphalt. At 82 °C, compared with SBS modified asphalt, the phase angle of PPA/SBS composite modified asphalt can be decreased by 8.63%, 13.23% and 19.24%, respectively, and G*/sinδ can be increased by 41.97%, 67.62% and 70.97%, respectively. SBS mainly exists in asphalt in the form of physical blending, and PPA has a new chemical reaction with asphalt, which increases the macromolecules and chain hydrocarbon components in asphalt, and the macroscopic performance is the improvement of high-temperature performance of asphalt. However, PPA has a negative effect on the low-temperature performance of the SBS modified asphalt.
The Effect of CO2 Laser Engraving on the Surface Structure and Properties of Spruce Wood
Authors: Kúdela Jozef , Andrejko Michal , Kubovský Ivan
Published: November 2023

This work appraises the influence of CO2 laser irradiation on mass loss, morphology, chemical changes and discolouration of spruce wood surfaces. The amount of energy applied to the surface was expressed as the total irradiation dose, which was demonstrated to have a strong impact on increasing wood weight loss. Along with increasing mass loss, surface roughness also increased, resulting from the differences in density between the early wood and late wood. The evaluated roughness parameters increased linearly with increasing irradiation dose and mass loss. At the maximum irradiation dose, the Ra parameter value parallel to the fibre direction showed a 6-fold increase; perpendicular to the grain, the increase was as much as 33.5-fold. Similar differences were also observed for the parameter Rz. At the lowest laser power and the lowest raster density, the engraved spruce wood surface exhibited some evidence of discolouration (ΔE* ≅ 9). An additional increase in the amount of supplied energy clearly resulted in a novel surface colour compared to the original (ΔE* = 12). The chemical analysis of the wood surface revealed that the discolouration was mainly caused by heat-induced cleavage of C=O groups in the lignin and hemicellulose structures. Part of these structures (so-called chromophores) are responsible for the natural colour of the wood as well as for colour changes caused by engraving. The detected dependences of the wood mass loss and colour values on the total radiation dose are the basis for achieving targeted modifications of spruce wood surfaces using a laser beam.
Effect of Melt Superheating Treatment on the Microstructures and Purity of a Directionally Solidified Superalloy
Authors: Li Yi , Zhang Qifei , You Xiaogang , Qiang Jianbing
Published: November 2023

In this paper, the effects and the mechanisms of melt superheating treatment (MST) on a directionally solidified alloy were investigated. The mass loss rate of the superalloy becomes severe as the MST temperature rises. The chromium, tantalum, and hafnium are the primary evaporation elements during MST. As the MST temperature increases from 1500 to 1600 °C, the secondary dendrite arm spacing is reduced by 13.3%, and the average size of γ′ particles are reduced by 11.5% and 18.2% in the dendrite core and inter-dendritic area, respectively. The content of oxygen and nitrogen gradually reduces with the increase in the MST temperature. However, the sulfur content is not significantly affected by the MST temperature. The essential cause of γ′ phases transition is supposed to be the MST-induced changes in solute distribution and the decomposition of atomic clusters. In addition, the nitrides and Ti (N, C)-type carbides are continuously dispersed as the MST temperature increases, which promotes the removal of nitrogen impurities.
Effect of Sn Addition on the Microstructure and Age-Hardening Response of a Zn-4Cu Alloy
Authors: Shamaki Aysha E. , Zahran Heba Y. , Abd El-Rehim Alaa F.
Published: November 2023

The aim of this research is to assess the influence of Sn inclusion on the microstructure evolution and age-hardening response of a Zn-4Cu alloy. This is the first study to correlate the age-hardening response to the microstructure of Zn-4Cu alloy reinforced with different Sn contents. A series of Zn-4Cu-Sn alloys were successfully fabricated with different Sn concentrations in the range of 0.0–4.0 wt.% using permanent mold casting. The microstructure of Zn-4Cu-Sn alloys was investigated by means of a scanning electron microscope (SEM) attached with an energy dispersive spectroscope (EDS) and X-ray diffraction (XRD) line profile analysis. At room temperature, the Vickers microhardness measurements were used to assess the age-hardening response of alloys. The results show that the microhardness of the Zn-4Cu (ZC) binary alloy increases a little bit from 76 to 80 HV as the aging time increases from 2 to 128 h, respectively. For aging times up to 16 h, the microhardness of all Sn-containing alloys decreases but then increases again. The lowest hardness belongs to the ZC-1.5Sn alloy, and the Sn-Zn-3.0Sn alloy has the highest; the other alloys fall somewhere in between. At high aging times (64 and 128 h), the microhardness of all Sn-containing samples increased continuously with an increasing Sn content from 0.0 to 3.0 wt.%. When the Sn-containing alloys (3.5 and 4.0 wt.% Sn) were aged for 64 and 128 h, the hardness declined by 7.94% and 8.90% compared to their peak aging hardness values, respectively. By considering the structural changes that occur in the Zn-4Cu-Sn alloys, the reasons for the observed variations in microhardness data with increasing Sn content and aging time were elucidated. X-ray diffraction (XRD) data was analyzed to determine the zinc matrix’s lattice parameters, c/a ratio, and unit cell volume variations.
In Situ Growth of Mg-Fe Layered Double Hydroxides (LDH) Film on Titanium Dental Implant Substrates for pH Regulation in Oral Environments
Authors: Li Yuliu , Gianfreda Francesco , Danesi Carlotta , Bollero Patrizio , Ermini Anita , Pizzoferrato Roberto , Nicolai Eleonora
Published: November 2023

Layered double hydroxides (LDHs) consist of two-dimensional, positively charged lamellar structures with the ability to host various anions in the interlayer spaces, which grants them unique properties and tunable characteristics. LDHs, a class of versatile inorganic compounds, have recently emerged as promising candidates for enhancing osseointegration. A suitable alkaline microenvironment is thought to be beneficial for stimulating osteoblasts’ differentiation (responsible for bone matrix formation) while suppressing osteoclast generation (responsible for bone matrix disintegration). LDHs are prone to adjusting their alkalinity and thus offering us the chance to study how pH affects cellular behavior. LDHs can indeed modulate the local pH, inflammatory responses, and oxidative stress levels, factors that profoundly influence the behavior of osteogenic cells and their interactions with the implant surface. Herein, we deposited Mg–Fe LDH films on titanium substrates for dental implants. The modified Ti substrates was more alkaline in comparison to the bare ones, with a pH higher than 8 after hydrolysis in an aqueous environment.
Recent Progress in True 3D Display Technologies Based on Liquid Crystal Devices
Authors: Liu Shuxin , Li Yan , Su Yikai
Published: November 2023

In recent years, the emergence of virtual reality (VR) and augmented reality (AR) has revolutionized the way we interact with the world, leading to significant advancements in 3D display technology. However, some of the currently employed 3D display techniques rely on stereoscopic 3D display method, which may lead to visual discomfort due to the vergence-accommodation conflict. To address this issue, several true 3D technologies have been proposed as alternatives, including multi-plane displays, holographic displays, super multi-view displays, and integrated imaging displays. In this review, we focus on planar liquid crystal (LC) devices for different types of true 3D display applications. Given the excellent optical performance of the LC devices, we believe that LC devices hold great potential for true 3D displays.
Nitrate Reduction Reaction on Zr-Doped TiO2 (101) Surfaces Investigated by First-Principles Calculations
Authors: He Xiyu , Yang Fan , Hu Qiaodan , Yin Jiewei , Zhang Junliang
Published: November 2023

Electrochemical nitrate reduction to ammonia is an efficient strategy for nitrate removal and ammonia production in ambient conditions. TiO2 is a promising electrocatalyst for such a reaction, but chemical doping is still needed to further improve the electrocatalytic properties of TiO2. Here, we investigated the effect of Zr-doping on the nitrate reduction reaction processes on the (101) surface of anatase TiO2 using first-principles calculations. Two models with different Zr-doping levels were built. The reaction pathways and the potential-determining steps were established based on a thorough investigation of the variation in Gibbs free energy of each possible elementary step. The results show that a high level of Zr doping was effective to lower the Gibbs free energy for nitrate adsorption; however, Zr doping may promote the competing hydrogen evolution reaction (HER) by reducing the adsorption Gibbs free energy of H. Moreover, Zr doping also increases the adsorption Gibbs free energies for the intermediate products NO2 and NO, which may result in an earlier termination of the reaction, by releasing the intermediates as the final products without producing ammonia. Therefore, Zr doping may decrease the Faradaic efficiency and selectivity of TiO2 for the reaction and should be treated with caution experimentally.
How the Hinge Region Affects Interactions between the Catalytic and β-Propeller Domains in Oligopeptidase B
Authors: Timofeev Vladimir , Gaponov Yury , Petrenko Dmitry , Peters Georgy , Agapova Yulia , Nikolaeva Alena , Mikhailova Anna , Rakitina Tatiana
Published: November 2023

In order to elucidate the effect of modification of the hinge region on structural polymorphism associated with conformational transitions, structural studies of hinge-modified oligopeptidase B from Serratia proteamaculans (SpOpBmod) in the crystalline state and solution were carried out. A new crystal structure of SpOpBmod in the intermediate conformation was obtained, and a molecular model of SpOpBmod in the open conformation was created using a combination of small-angle X-ray scattering with MD simulations. The improved electron density of the mobile H-loop carrying the catalytic H652 distinguished the obtained crystal structure from that which was previously reported. Good electron density in this region was previously found only in the inhibitor-bound SpOpBmod structure, in which one of the inhibitor molecules was covalently bound to H652. Comparison of the above structures of free and inhibitor-bound enzymes showed that both tertiary folds are the result of the internal conformational dynamics of SpOpBmod, which were captured by inhibitor binding. Comparison of the SpOpBmod structures with the structures of the same enzyme with a native hinge peptide made it possible to establish the influence of hinge modification on the rearrangement of the interdomain interface during conformational transitions. The above analysis also used models of native and hinge-modified enzymes in open conformations. We found that the interdomain interface observed in the crystal structures of hinge-modified enzymes could be considered an extreme version of the H-loop arrangement, in which closure of the domains does not lead to the assembly of the catalytic triad, whereas the intermediate conformation observed in the structure of the enzyme with the native hinge sequence illustrates a productive transition to the catalytically active closed conformation.
Meta-heuristic Algorithms in UAV Path Planning Optimization: A Systematic Review (2018–2022)
Authors: Hooshyar Maral , Huang Yueh-Min
Published: November 2023

Unmanned Aerial Vehicles (UAVs), a subset of aerial robots, play crucial roles in various domains, such as disaster management, agriculture, and healthcare. Their application proves invaluable in situations where human intervention poses risks or involves high costs. However, traditional approaches to UAV path planning struggle in efficiently navigating complex and dynamic environments, often resulting in suboptimal routes and extended mission durations. This study seeks to investigate and improve the utilization of meta-heuristic algorithms for optimizing UAV path planning. Toward this aim, we carried out a systematic review of five major databases focusing on the period from 2018 to 2022. Following a rigorous two-stage screening process and a thorough quality appraisal, we selected 68 papers out of the initial 1500 to answer our research questions. Our findings reveal that hybrid algorithms are the dominant choice, surpassing evolutionary, physics-based, and swarm-based algorithms, indicating their superior performance and adaptability. Notably, time optimization takes precedence in mathematical models, reflecting the emphasis on CPU time efficiency. The prevalence of dynamic environmental types underscores the importance of real-time considerations in UAV path planning, with three-dimensional (3D) models receiving the most attention for accuracy in complex trajectories. Additionally, we highlight the trends and focuses of the UAV path planning optimization research community and several challenges in using meta-heuristic algorithms for the optimization of UAV path planning. Finally, our analysis further highlights a dual focus in UAV research, with a significant interest in optimizing single-UAV operations and a growing recognition of the challenges and potential synergies in multi-UAV systems, alongside a prevalent emphasis on single-target mission scenarios, but with a notable subset exploring the complexities of multi-target missions.
Using Unoccupied Aerial Systems (UASs) to Determine the Distribution Patterns of Tamanend’s Bottlenose Dolphins (Tursiops erebennus) across Varying Salinities in Charleston, South Carolina
Authors: Principe Nicole , McFee Wayne , Levine Norman , Balmer Brian , Ballenger Joseph
Published: November 2023

The Charleston Estuarine System Stock (CESS) of Tamanend’s bottlenose dolphins (Tursiops erebennus) exhibit long-term site fidelity to the Charleston Harbor, and the Ashley, Cooper, and Wando Rivers in Charleston, South Carolina, USA. In the Cooper River, dolphins have been irregularly sighted in upper regions where salinity levels are below what is considered preferred dolphin habitat. We conducted unoccupied aerial system (UAS) surveys in high-salinity (>15 parts per thousand) and low-salinity (<15 parts per thousand) regions (n = 8 sites) of the Cooper River and surrounding waters to assess dolphin distribution in terms presence/absence, detection rate, abundance, and density. We also assessed the influence of ecological factors (salinity, water temperature, season, and prey availability) on dolphin distribution. Dolphins were detected at five sites, with higher salinity and water temperature being significant predictors of presence and abundance. Dolphins were detected year-round across high-salinity sites, and were infrequently detected in low-salinity sites during months with warmer water temperatures. The results from this study contribute to the overall understanding of dolphin distribution across various habitats within the Charleston Estuary System and the potential drivers for their movement into low-salinity waters.