bluuebunny/crossref_metadata_2025 huggingface dataset:
Soft-Matter Physics Provides New Insights on Myocardial Architecture: Automatic and Quantitative Identification of Topological Defects in the Trabecular Myocardium
Authors: Auriau Johanne , Usson Yves , Jouk Pierre-Simon
Published: December 2023

This article is the third in our series dedicated to the analysis of cardiac myoarchitecture as a nematic chiral liquid crystal (NCLC). Previously, we introduced the concept of topological defects (disclinations) and focused on their visual identification inside the compact myocardium. Herein, we investigate these using a mathematical and automated algorithm for the reproducible identification of a larger panel of topological defects throughout the myocardium of 13 perinatal and 11 early infant hearts. This algorithm identified an average of 29 ± 11 topological defects per slice with a 2D topological charge of m = +1/2 and an average of 27 ± 10 topological defects per slice with a 2D topological charge of m = −1/2. The excess of defects per slice with a 2D topological charge of m = +1/2 was statistically significant (p < 0.001). There was no significant difference in the distribution of defects with a 2D topological charge of m = +1/2 and m = −1/2 between perinatal and early infant hearts. These defects were mostly arranged in pairs, as expected in nematics, and located inside the trabecular myocardium. When isolated, defects with a 2D topological charge of m = +1/2 were located near the luminal extremity of the trabeculae and those with a 2D topological charge of m = −1/2 were located at the anterior and posterior part of the interventricular septum. These findings constitute an advance in the characterization of the deep cardiac myoarchitecture for application in developmental and pathological studies.
Diagnostic Yield of High-Resolution Vessel Wall Magnetic Resonance Imaging in the Evaluation of Young Stroke Patients
Authors: Simaan Naaem , Jubeh Tamer , Shalabi Fatma , Jubran Hamza , Metanis Issa , Parag Yoav , Schwartzman Yoel , Magadlla Jad , Gomori John. M. , Beiruti Karine Wiegler , Cohen Jose E. , Leker Ronen
Published: December 2023

(1) Background: The mechanism responsible for stroke in patients younger than 50 often remains unknown. This study was designed to assess whether high-resolution intracranial vessel wall MR imaging (icVWI) may be instrumental in determining stroke cause. (2) Methods: Young stroke patients with and without an identified cause of stroke despite an exhaustive investigation were prospectively included. Patients who underwent icVWI were compared to those who did not. We next compared patients with and without intracranial vulnerable plaques on icVWI. (3) Results: Overall, 47 young stroke patients were identified over the span of 2 years and included in this study. Of those, 20 (42%) underwent intracranial icVWI. Cancer prevalence was higher among patients who did not have an icVWI study (19% vs. 0% p = 0.042) but there were no other significant differences between patients who had an icVWI study and those who did not have an icVWI. Among patients who had an icVWI, 11 (55%) had vulnerable plaques and the remaining nine studies were negative. Patients with positive icVWI scans had significantly higher stroke severity at admission (mean ± SD NIHSS score 5.5 ± 3.5 vs. 1.7 ± 2.3, p = 0.012). Patients with positive icVWI scans were more often treated with antiplatelets upon discharge (100% vs. 67%, p = 0.038). (4) Conclusions: icVWI can add significant information relevant to stroke pathogenesis and secondary prevention among young stroke patients with a negative exhaustive diagnostic workup.
Intraoperative Extracorporeal Support during Lung Transplantation: Not Just for the High-Risk Patient
Authors: Laskey Daniel , Housman Brian , Dawodu Gbalekan , Scheinin Scott
Published: December 2023

The use of intraoperative mechanical support during lung transplantation has traditionally been a controversial topic. Trends for intraoperative mechanical support strategies swing like a pendulum. Historically, cardiopulmonary bypass (CPB) was the modality of choice during transplantation. It provides full hemodynamic support including oxygenation and decarboxylation. Surgical exposure is improved by permitting the drainage of the heart and provides more permissive retraction. CPBs contain drainage reservoirs with hand-held pump suction catheters promoting blood conservation through collection and re-circulation. But CPB has its disadvantages. It is known to cause systemic inflammation and coagulopathy. CPB requires high doses of heparinization, which increases bleeding risks. As transplantation progressed, off-pump transplantation began to trend as a preferable option. ECMO, however, has many of the benefits of CPB with less of the risk. Outcomes were improved with ECMO compared to CPB. CPB has a higher blood transfusion requirement, a higher need for post-operative ECMO support, a higher re-intubation rate, high rates of kidney injury and need for hemodialysis, longer ICU stays, higher incidences of PGD grade 3, as well as overall in-hospital mortality when compared with ECMO use. The focus now shifts to using intraoperative mechanical support to protect the graft, helping to reduce ischemia-reperfusion injury and allowing for lung protective ventilator settings. Studies show that the routine use of ECMO during transplantation decreases the rate of primary graft dysfunction and many adverse outcomes including ventilator time, need for tracheostomy, renal failure, post-operative ECMO requirements, and others. As intraoperative planned ECMO is considered a safe and effective approach, with improved survival and better overall outcomes compared to both unplanned ECMO implementation and off-pump transplantation, its routine use should be taken into consideration as standard protocol.
Improving Cardiovascular Risk in Postmenopausal Women with an (−)-Epicatechin-Based Nutraceutical: A Randomly Assigned, Double-Blind vs. Placebo, Proof-of-Concept Trial
Authors: Nájera Nayelli , Ortíz-Flores Miguel , Pérez-Durán Javier , Reyes-Muñoz Enrique , Romo-Yañez José , Ortiz-Luna Guillermo , Villarreal Francisco , Meaney Eduardo , Ceballos Guillermo , Montoya-Estrada Araceli
Published: December 2023

Background: Age-adjusted rates of cardiovascular disease (CVD) are higher in men than in women. CVD risk-factor outcomes are underrecognized, underestimated, and undertreated in women because the clinical expressions in women differ from those of men. There are no universally accepted recommendations on what to do in women when the values of fasting glucose, blood pressure, and lipids are only slightly altered or at borderline values. We reported the positive effects on CVD risk markers using cacao by-products, showing that alternative approaches can be used to prevent cardiovascular disease in women. The objective was to evaluate the changes in lipoprotein subfractions induced by three months of treatment with an epicatechin-enriched cacao supplement. Methods: A double-blind, placebo-controlled proof-of-concept study was developed to evaluate the effects of 3 months of treatment with an (−)-epicatechin-enriched cacao supplement on lipoprotein subfractions. Results: The usual screening workshop for postmenopausal women could be insufficient and misleading. Assessing the effect of a (−)-epicatechin-enriched cacao supplement employing a lipoprotein subfractionation profile analysis suggests a decrease in cardiovascular risk. Conclusions: A simple, low-cost, safe (−)-epicatechin-enriched cacao supplement product can improve the cardiovascular risk in postmenopausal women.
Incretin Therapies for Patients with Type 2 Diabetes and Chronic Kidney Disease
Authors: Alicic Radica Z. , Neumiller Joshua J.
Published: December 2023

Since the early 2000s, an influx of novel glucose-lowering agents has changed the therapeutic landscape for treatment of diabetes and diabetes-related complications. Glucagon-like peptide-1 (GLP-1) receptor agonists represent an important therapeutic class for the management of type 2 diabetes (T2D), demonstrating benefits beyond glycemic control, including lowering of blood pressure and body weight, and importantly, decreased risk of development of new or worsening chronic kidney disease (CKD) and reduced rates of atherosclerotic cardiovascular events. Plausible non-glycemic mechanisms that benefit the heart and kidneys with GLP-1 receptor agonists include anti-inflammatory and antioxidant effects. Further supporting their use in CKD, the glycemic benefits of GLP-1 receptor agonists are preserved in moderate-to-severe CKD. Considering current evidence, major guideline-forming organizations recommend the use of GLP-1 receptor agonists in cases of T2D and CKD, especially in those with obesity and/or in those with high cardiovascular risk or established heart disease. Evidence continues to build that supports benefits to the heart and kidneys of the dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide. Ongoing outcome and mechanistic studies will continue to inform our understanding of the role of GLP-1 and dual GLP-1/GIP receptor agonists in diverse patient populations with kidney disease.
Impact of Adjuvant Radiotherapy on Free Flap Volume in Autologous Breast Reconstruction: A Scoping Review
Authors: Pfister Pablo , Müller Seraina L. C. , Eberhardt Anna-Lena , Rodriguez Medea , Menzi Nadia , Haug Martin , Schaefer Dirk J. , Kappos Elisabeth A. , Ismail Tarek
Published: December 2023

In autologous breast reconstruction, a sufficient flap volume is fundamental to restore breast shape and ensure an aesthetic outcome. After mastectomy, postoperative irradiation is regularly indicated in the oncological treatment algorithm. When administering radiation therapy after autologous reconstruction, the tissue transferred is inherently irradiated. Although there is evidence that points to a reduction in flap volume after adjuvant radiotherapy, the data have been contradicting and inconclusive. To address this anecdotal evidence, we performed a scoping review of the current literature that addresses the effect of radiotherapy on breast flap volume. Six two-armed studies, comprising a total of 462 patients, reported on the effect of adjuvant radiotherapy on free flap volume changes. Of those, two studies found a significant negative impact of radiotherapy on free flap volume, while the other four studies did not. Reported flap volume changes ranged from no change to a reduction of 26.2%, measured up to two years postoperatively. The selected studies contain varying patient numbers, follow-up timepoints, types of flaps, and measuring methods, contributing to a relatively high heterogeneity. While we present some evidence suggesting a significant impact of adjuvant radiotherapy on breast flap volume, future studies are needed to further investigate this potential correlation.
Late Holocene Climate Warming Events and Their Linkage to Hydraulic Engineering on the Coast of Hangzhou Bay, East China
Authors: Li Xunpeng , You Xiaolei , Lin Sen , Zhang Wentong , Cheng Zeen , Wang Zhanghua
Published: December 2023

The coastal lowlands in East China are very sensitive to climate change and marine disasters, and much large-scale hydraulic engineering was recorded in the historical documents of the Late Holocene. In this study, AMS 14C and OSL were used to date three sedimentary profiles from the north and south coasts of inner Hangzhou Bay, and grain size and geochemical analyses including organic carbon, macro-elements, and alkaline earth metals were performed, while hydraulic engineering records in historical documents were compiled, in an attempt to reveal the sedimentary records of extreme climatic and hydrological events over the past 3000 years and to probe into the correlation between them and hydraulic engineering. The results show that the intensified chemical weathering during ca. 200 BCE to 900 CE in East China corresponded to the warm and humid climate during the Qin-Han and Sui-Tang dynasties. Salinity intrusion with rising local water levels occurred in the lowland plains along the south coast of Hangzhou Bay from 120 to 895 CE. Low-salinity water intrusion from 32 to 488 CE was also recorded in the stratigraphy of lowland plains along the north coast of Hangzhou Bay. The sedimentary records of the East Tiaoxi River basin show river floods about 2000 years ago. The above sedimentary records indicate that the relative sea level rose in the Hangzhou Bay area during the Qin-Han and Sui-Tang Warm Periods, resulting in frequent salinity intrusion and river floods, which coincided with the historical records of hydraulic engineering such as the construction of seawalls, river levees, and the enclosure of lakes for restoration of river floods during the Han and Tang dynasties. Such coincidence reflects that climate change profoundly affected the hydrological environment of the coastal areas in East China as well as the response of the human societies.
Foliar Lesions Induced by Pestalotiopsis arengae in Oil Palm (O × G) in the Colombian Southwest Palm Zone
Authors: Betancourt-Ortiz William Fabian , Medina-Cardenas Hector Camilo , Padilla-Agudelo Jose Luis , Varon Francia Helena , Mestizo-Garzón Yuri Adriana , Morales-Rodríguez Anuar , Sarria-Villa Greicy Andrea
Published: December 2023

In Colombia, plantings with the oil palm hybrid between Elaeis oleifera × Elaeis guineensis, known as O × G hybrid, have increased due to its tolerance to bud rot. Despite this, different degrees of foliar necrosis, chlorosis, and leaf blight have been reported in some cultivars; therefore, this work aimed to diagnose this problem. We visited plantation plots with palms exhibiting the mentioned symptoms and collected 21 samples of affected tissues in different disease states. The affected tissues were examined and seeded in a culture medium. Pathogenicity tests were performed and the isolates were characterized by culture and morphological and molecular features. Curvularia, Colletotrichum, Phoma, and 25 Pestalotiopsis-like fungi were isolated from the foliar lesions. In the pathogenicity tests, the symptoms observed in the field were reproduced with MFTU01-1, MFTU12, and MFTU21 isolates, which were identified at the species level through a sequence analysis of three genes (ITS, TUB2, and TEF1-α) as Pestalotiopsis arengae with an identical level of 99% based on the results of BLAST and phylogenetic tree analyses. The remaining 22 Pestalotiopsis-like non-pathogenic isolates were identified as species of Neopestalotiopsis and Pseudopestalotiopsis. The direct association of P. arengae with the disease was confirmed via molecular detection in affected tissues in 15 of 21 samples collected for this evaluation. This is the first report of P. arengae as the causal agent of foliar lesions in O × G hybrid oil palm in Colombia.
Personalization of Therapy in High-Grade Serous Tubo-Ovarian Cancer—The Possibility or the Necessity?
Authors: Wilczyński Jacek , Paradowska Edyta , Wilczyński Miłosz
Published: December 2023

High-grade serous tubo-ovarian cancer (HGSTOC) is the most lethal tumor of the female genital tract. The foregoing therapy consists of cytoreduction followed by standard platinum/taxane chemotherapy; alternatively, for primary unresectable tumors, neo-adjuvant platinum/taxane chemotherapy followed by delayed interval cytoreduction. In patients with suboptimal surgery or advanced disease, different forms of targeted therapy have been accepted or tested in clinical trials. Studies on HGSTOC discovered its genetic and proteomic heterogeneity, epigenetic regulation, and the role of the tumor microenvironment. These findings turned attention to the fact that there are several distinct primary tumor subtypes of HGSTOC and the unique biology of primary, metastatic, and recurrent tumors may result in a differential drug response. This results in both chemo-refractoriness of some primary tumors and, what is significantly more frequent and destructive, secondary chemo-resistance of metastatic and recurrent HGSTOC tumors. Treatment possibilities for platinum-resistant disease include several chemotherapeutics with moderate activity and different targeted drugs with difficult tolerable effects. Therefore, the question appears as to why different subtypes of ovarian cancer are predominantly treated based on the same therapeutic schemes and not in an individualized way, adjusted to the biology of a specific tumor subtype and temporal moment of the disease. The paper reviews the genomic, mutational, and epigenetic signatures of HGSTOC subtypes and the tumor microenvironment. The clinical trials on personalized therapy and the overall results of a new, comprehensive approach to personalized therapy for ovarian cancer have been presented and discussed.
Association between the Number of Days/Week of Different Levels of Physical Activity and Chronic Pain in People of Different Races: A Mendelian Randomization Study
Authors: Luo Sumei , Yang Minjing , Yang Haojun , Guo Qulian , Wang Yunjiao , Wang E
Published: December 2023

Objective: Regular physical activity is beneficial for health, but the effect of the number of days/week of physical activity on chronic pain (CP) remains unclear, so we used a two-sample Mendelian randomization (MR) analysis to explore the relationship between the number of days/weeks of different levels of physical activity and chronic pain in people of different races. Methods: We obtained summary data from genome-wide association studies (GWASs) on the number of days/week of physical activity and multisite chronic pain in European, South Asian, East Asian, Middle Eastern, and African American populations. The single-nucleotide polymorphisms (SNPs) of the exposed data were visualized with a Manhattan plot via the R program. MR analysis was performed by the MR-Base platform. Results: The results indicated that a higher number of days/week with ≥10 min of walking protects against CP in African American and Afro-Caribbean populations (inverse-variance weighting, IVW p < 0.05) but has little effect on people of different races (IVW p > 0.05). A higher number of days/week with ≥10 min of moderate physical activity increased the risk of CP in European and South Asia (IVW p < 0.05) but had little effect on people of different races (IVW p > 0.05). The number of days/week of ≥10 min of vigorous physical activity increased the risk of CP in Europeans (IVW p < 0.05) and protected against CP in African Americans and Afro-Caribbeans (IVW p < 0.05). Conclusions: A higher number of days/week of moderate and vigorous physical activity increased the risk of CP in Europeans; however, a higher number of days/week of walking and vigorous physical activity may protect against CP in African American and Afro-Caribbean individuals.
Can the Conditional Rebate Strategy Work? Signaling Quality via Induced Online Reviews
Authors: Xiao Lu , Qian Chen , Wang Chaojie , Wang Jun
Published: December 2023

Online reviews are an important part of product information and have important effects on consumers’ purchasing decisions. Some sellers try to manipulate the market by inducing online reviews. In this study, a signal game model based on Bayesian conditional probability is constructed to analyze the preconditions, decision-making process, and effect on market demand and profit of this behavior. The results show that first, when consumer sensitivity to rebates reaches a certain threshold, low-quality sellers will adopt a conditional rebate strategy to induce consumers to give positive reviews. Second, the optimal rebate cost (β*) is obtained, where β* increases with the product price (p), but it is not necessarily monotonic in consumers’ sensitivity to rebates (ρ) or the proportion of high-quality products (α). Third, the conditional rebate strategy can only work in a market dominated by low-quality goods. Using the conditional rebate strategy in a market dominated by high-quality goods will not bring benefits to low-quality sellers but will harm their profits. This study proposes that some developing online markets have collusive behaviors owing to a lack of regulations and laws, as well as consumers’ concern for small interests. Ensuring the orderly development of online markets will require joint efforts by platform enterprises, government agencies, and consumers.
Genetic Association and Differential RNA Expression of Histone (De)Acetylation-Related Genes in Pemphigus Foliaceus—A Possible Epigenetic Effect in the Autoimmune Response
Authors: Sulzbach Denardin Maiara , Bumiller-Bini Hoch Valéria , Salviano-Silva Amanda , Lobo-Alves Sara Cristina , Adelman Cipolla Gabriel , Malheiros Danielle , Augusto Danillo G. , Wittig Michael , Franke Andre , Pföhler Claudia , Worm Margitta , van Beek Nina , Goebeler Matthias , Sárdy Miklós , Ibrahim Saleh , Busch Hauke , Schmidt Enno , Hundt Jennifer Elisabeth , Petzl-Erler Maria Luiza , Beate Winter Boldt Angelica
Published: December 2023

Pemphigus foliaceus (PF) is an autoimmune skin blistering disease characterized by antidesmoglein-1 IgG production, with an endemic form (EPF) in Brazil. Genetic and epigenetic factors have been associated with EPF, but its etiology is still not fully understood. To evaluate the genetic association of histone (de)acetylation-related genes with EPF susceptibility, we evaluated 785 polymorphisms from 144 genes, for 227 EPF patients and 194 controls. Carriers of HDAC4_rs4852054*A were more susceptible (OR = 1.79, p = 0.0038), whereas those with GSE1_rs13339618*A (OR = 0.57, p = 0.0011) and homozygotes for PHF21A_rs4756055*A (OR = 0.39, p = 0.0006) were less susceptible to EPF. These variants were not associated with sporadic PF (SPF) in German samples of 75 SPF patients and 150 controls, possibly reflecting differences in SPF and EPF pathophysiology. We further evaluated the expression of histone (de)acetylation-related genes in CD4+ T lymphocytes, using RNAseq. In these cells, we found a higher expression of KAT2B, PHF20, and ZEB2 and lower expression of KAT14 and JAD1 in patients with active EPF without treatment compared to controls from endemic regions. The encoded proteins cause epigenetic modifications related to immune cell differentiation and cell death, possibly affecting the immune response in patients with PF.
Alien Algae Species Invasions in Humic Rivers within Weakly Human Impact Basin
Authors: Kulizin Pavel , Vodeneeva Ekaterina , Martynenko Nikita , Sharagina Ekaterina , Okhapkin Alexander
Published: December 2023

Increasing anthropogenic influence and climate change are leading to significant transformations in living conditions for indigenous representatives of aquatic communities. The problem of alien species invasions is actively discussed in the example of large rivers and water reservoirs, but medium and small rivers with weak anthropogenic influence have been insufficiently studied in this aspect. With the help of analysis of literary data and the results of our own long-term observations of phytoplankton using morphological and molecular genetic methods in some left-bank Volga tributaries, we identified six invasive species of different taxonomic groups of algae, with a predominance of diatoms. The relevance of using both traditional and modern approaches to identifying invasive algae species is revealed. Such invasive species as Thalassiosira incerta, T. faurii, Skeletonema subsalsum, Unruhdinium kevei, and Gonyostomum semen were part of planktonic communities; the benthic species Plagiotropis lepidoptera var. proboscidea sometimes reached a significant level of development (up 6 to 44% from total biomass) in plankton. It was demonstrated that some algae species have firmly taken the position of dominants and subdominants in planktonic algae communities. The expansion of alien representatives of microphytobenthos was noted in the Volga River basin for the first time. For Gonyostomum semen, its European origin was revealed, for plankton and benthic diatom—Ponto-Caspian. Our study showed that the processes of invasion and subsequent development of alien species take place in habitats with weak anthropogenic influence, which is likely determined by the hydrological, hydrochemical, and climatic changes in river basins and the high adaptive capabilities of invasive species.
Numerical Simulation on Solidification during Vertical Centrifugal Casting Process for TC4 Alloy Wheel Hub with Enhanced Mechanical Properties
Authors: Yang Yujie , Wang Xiangyi , Li Xiangming , Zhou Rongfeng , He Zhengyuan , Jiang Yehua
Published: December 2023

The Ti-6Al-4V (TC4) alloy wheel hub has exhibited some defects that affect the properties during the vertical centrifugal casting process. Therefore, the analysis of the solidification process would contribute to solving the above-mentioned problems. In this study, an orthogonal experimental design was employed to optimize the process parameters (rotational speed, mold preheating temperature, and pouring temperature) of the vertical centrifugal casting method. The effects of process parameters on the velocity field, temperature field, and total shrinkage porosity during the solidification process were explored, and the microstructure and mechanical properties of the wheel hub prepared by the vertical centrifugal casting method were also investigated. The results showed that the rotational speed mainly induced the change of the velocity field. The pouring temperature and mold preheating temperature affected the temperature field and solidification time. Based on the analysis of the orthogonal experiment, the optimal parameters were confirmed as a rotational speed of 225 rpm, mold preheating temperature of 400 °C, and pouring temperature of 1750 °C, respectively. The simulation results of total shrinkage porosity were in agreement with the experiment results. The wheel hub was composed of nonuniform α and β phases. The lath α phase precipitated from larger β grains with different orientations. Compared with the other samples at different locations, the α phase in the PM sample (middle of the TC4 wheel hub) displayed high peak intensity and uniformly distributed β phase along the radial direction of the wheel hub. Moreover, the PM sample revealed a higher tensile strength of 820 MPa and similar Vickers hardness of 318 HV compared with the other samples at different locations, which were higher than those of rolling and extrusion molding. This experiment design would provide a good reference for the vertical centrifugal casting of the TC4 alloy.
Assessing and Forecasting ISR-Affected Critical Infrastructure: State-of-the-Art and Challenges
Authors: Bergmann Ana , Medeiros Rennan , Sanchez Leandro
Published: December 2023

Internal swelling reactions (ISRs) are among the most critical deterioration mechanisms affecting infrastructure’s durability worldwide. While preventative measures for new structures have been extensively explored, effective protocols for diagnosing and prognosing ISR-affected structures, especially at their early stages, are still required. Therefore, through a comprehensive bibliometric analysis, this study focuses on exploring the evolution and current methods for assessing and forecasting ISR damage in concrete structures. For diagnosis, a shift from concrete petrography and non-destructive techniques (NDTs) towards more comprehensive methods (i.e., multi-level assessment) with the stiffness damage test (SDT) and damage rating index (DRI) is observed. Moreover, it identifies the valuable inputs from residual expansion and pore solution analysis as relevant parameters for prognosis. Based on these findings, a structured management framework is proposed aiming to refine the diagnosis and prognosis processes of ISR-affected infrastructure, ultimately contributing to improved long-term structural health and maintenance strategies.
Temperature Influence on Brake Pad Friction Coefficient Modelisation
Authors: Bellini Costanzo , Di Cocco Vittorio , Iacoviello Daniela , Iacoviello Francesco
Published: December 2023

Brake pad linings are an essential part of the correct functioning of braking systems based on the use of pads and discs. Generally, the compounds used to make the gaskets are characterised by the use of over 20 sintered components, which allow friction coefficients that vary between 0.2 and 0.6 at temperatures up to 200 °C. In this work, a traditional compound was investigated under close-to-real conditions in order to evaluate the tribological behaviour at different temperatures. Finally, a model based on the proportionality between temperature increase and relative variation of the friction coefficient was proposed. From the experimental test, it was evident that the friction coefficient increased with the temperature, passing from 0.4 to 0.6 in the temperature range of 100 °C to 180 °C; however, a further temperature increment until 350 °C caused a reduction in the friction coefficient to 0.2. The proposed model was able to anticipate the abovementioned trend, especially at high temperatures.
Photocatalytic Activity and Self-Cleaning Effect of Coating Mortars with TiO2 Added: Practical Cases in Warm Sub-Humid Climates
Authors: Kuk-Dzul Liliana , Jiménez Luis F. , Vega-Azamar Ricardo E. , Gurrola Mayra P. , Cruz Julio C. , Trejo-Arroyo Danna L.
Published: December 2023

In this study, the photocatalytic activity of coating mortars with synthetized and commercial TiO2 nanoparticles added has been evaluated at 2, 3 and 5% by weight of cement by calculating the degradation efficiency of methyl orange and red wine dyes exposed to both visible-light and UV radiation; also, the self-cleaning effect of coatings exposed to weather conditions (warm sub-humid climate) was assessed. TiO2 nanoparticles were synthesized via the sol–gel method to a low synthesis temperature and characterized via X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results show synthesized TiO2 particles in anatase phase with a crystallite size of 14.69 nm, and hemispherical particles with sizes of submicron order. The addition percentage with the best performance in the coating mortars was 3%, with both commercial and synthesized TiO2; however, coating mortars with synthesized TiO2 exhibited the highest degradation efficiency for both dyes when they were exposed to visible light, while mortars with commercial TiO2 exhibited the highest degradation efficiency when exposed to UV radiation. In addition, in coating mortars with synthesized TiO2, the self-cleaning effect was evident from the beginning of exposure to weather, reaching the largest dye-free surface at the end of exposure. The compressive strength increased significantly in mortars with TiO2 addition.
Study on Quench Sensitivity during Isothermal Treatment of 7A65 Aluminum Alloy
Authors: Li Chen , Bao Liangliang , Huang Ke , Huang Shiquan
Published: December 2023

The quenching sensitivity of 7A65 aluminum alloy was investigated using interrupted quenching experiments. The time–temperature transformation (TTT) and time–temperature performance (TTP) curves of the alloy were determined. The results indicate that the nose temperature is about 320 °C and the quenching sensitivity temperature range is from 240 °C to 360 °C. During the isothermal treatment, the supersaturated solid solution resolves to the equilibrium phase of η (MgZn2), and the precipitation rate is the largest at about 320 °C. Through transmission electron microscope (TEM) observation and X-ray diffraction (XRD) tests, it was found that with the extension of the isothermal holding time, the originally dispersed η’ phase gradually decreases until disappear, and the number of η phase increases and gradually grows up at the grain boundary or around the Al3Zr particles. The rod-like η phase at the grain boundary is distributed from discontinuous distribution to chain-like continuous distribution, and the precipitation free zone (PFZ) is gradually generated and widened as the holding time is extended. At the nose temperature, the driving force of nucleation is high, and the diffusion rate is fast, which promotes the precipitation and growth of η phases. The coarse η phase weakens the mechanical properties. According to the results, it is recommended to increase the cooling rate at the sensitivity temperature range to reduce the precipitation of the η phase and decrease the quenching cooling rate from solution temperature to 360 °C to reduce residual stresses in the components.
Strengthening Device for Improving Shear Performance of Anchor Cable in Rock Support
Authors: Feng Chao , Liu Shaowei , Jia Housheng , Fu Mengxiong , He Deyin
Published: December 2023

Many designs of anchor cables are currently in use for rock support in civil and mining operations. Because of the exposed surface and weak shear performance of the cable bolt’s free section (CBFS) in end-anchored structures, breaking failure frequently occurs. Numerical simulations and laboratory experiments were performed in this study to develop measures to improve CBFS resistance to shear failure. Analysis of shear characteristics of the CBFS showed that higher axial tension weakens the cable bolt’s shear resistance, and that shear damage on the cable surface and uneven distribution of shear stress aggravate CBFS tensile–shear failure. A high-strength steel pipe is proposed to protect the shear cable bolt, and the preliminary design of a CBFS-strengthening device (CFSD) is presented. Numerical simulation revealed that the CFSD effectively improved CBFS shear resistance and provided protection from harmful shear damage. The optimal performance of a Q-type (slotted steel pipe) CFSD was confirmed. The mechanism of improvement of the cable’s shear resistance to surrounding rock by employing the CFSD was analyzed. Double-shear tests were carried out on a bare cable bolt and a cable bolt with a Q-CFSD. The results revealed that the CFSD increased the peak shear force on the joint plane, cable peak axial force, and ultimate shear displacement by 31%, 18%, and 11%, respectively. The proposed device is effective in improving the shear performance of end-anchored cable bolts and enhancing surrounding rock stability.
Dynamic Power Provisioning System for Fog Computing in IoT Environments
Authors: Al Masarweh Mohammed , Alwada’n Tariq
Published: December 2023

Large amounts of data are created from sensors in Internet of Things (IoT) services and applications. These data create a challenge in directing these data to the cloud, which needs extreme network bandwidth. Fog computing appears as a modern solution to overcome these challenges, where it can expand the cloud computing model to the boundary of the network, consequently adding a new class of services and applications with high-speed responses compared to the cloud. Cloud and fog computing propose huge amounts of resources for their clients and devices, especially in IoT environments. However, inactive resources and large number of applications and servers in cloud and fog computing data centers waste a huge amount of electricity. This paper will propose a Dynamic Power Provisioning (DPP) system in fog data centers, which consists of a multi-agent system that manages the power consumption for the fog resources in local data centers. The suggested DPP system will be tested by using the CloudSim and iFogsim tools. The outputs show that employing the DPP system in local fog data centers reduced the power consumption for fog resource providers.
Anti-Inflammatory and Proangiogenic Metabolites from the Hadal Trench-Derived Fungus Acremonium dichromosporum YP-213
Authors: Zhang Yan , Zhou Jia-Bao , Yang Shu-Ting , Liu Xin , Cao Wei , Li Pei-Hai , Chen Hao , Fan Ya-Qin
Published: December 2023

Four new compounds, including two ascochlorin-type meroterpenoids acremocholrins A (1) and B (2), one pyridone alkaloid acremopyridone A (7), and one cyclopentenone derivative acremoketene A (12), together with eight known compounds (3–6 and 8–11), were isolated and identified from the hadal trench-derived fungus Acremonium dichromosporum YP-213. Their structures were determined with a detailed spectroscopic analysis of NMR and MS data, NOE analysis, octant rule and quantum chemical calculations of ECD, and NMR (with DP4+ probability analysis). Among the compounds, 7 represent a novel scaffold derived from a pyridone alkaloid by cleavage of the C-16-C-17 bond following oxidation to give a ketone. Compounds 9, 11, and 12 showed potent in vivo anti-inflammatory activity in transgenic zebrafish, while compound 8 exhibited significant proangiogenic activity in transgenic zebrafish.
Effects of Pelvic Floor Muscle Physiotherapy on Urinary, Bowel, and Sexual Functions in Women with Deep Infiltrating Endometriosis: A Randomized Controlled Trial
Authors: Del Forno Simona , Cocchi Laura , Arena Alessandro , Pellizzone Valentina , Lenzi Jacopo , Raffone Antonio , Borghese Giulia , Paradisi Roberto , Youssef Aly , Casadio Paolo , Raimondo Diego , Seracchioli Renato
Published: December 2023

Background and Objectives: Endometriosis is a chronic and recurrent disease defined as the presence and proliferation of endometrial glands and stroma outside the uterine cavity. It affects up to 6–10% of women of reproductive age and can be classified into superficial, ovarian, and deep infiltrating endometriosis (DIE). Deep infiltrating endometriosis can be associated with pain symptoms and pelvic floor muscle hypertone. Moreover, it may be responsible of bowel, urinary, and sexual dysfunctions with impairment of women’s quality of life. Few studies have investigated the role of physiotherapy in women with DIE. Here, we aimed first to evaluate the effects of pelvic floor physiotherapy (PFP) on urinary, bowel, and sexual functions. Secondly, we aimed to evaluate the effects of ultrasound visual feedback during PFP on pelvic floor and subjective modifications in the frequency of sexual intercourse. Materials and Methods: This randomized controlled trial was conducted between June 2018 and December 2019 at our tertiary center. Nulliparous women with DIE and superficial dyspareunia were enrolled. At first examination, levator hiatal area (LHA) assessed with 3D/4D transperineal ultrasound, pain symptoms, urinary, bowel, and sexual functions were evaluated. Then, women were randomly assigned to no intervention (control group) or treatment with five individual sessions of PFP (experimental group), and after four months women underwent a second examination. Urinary, bowel, and sexual functions were assessed with validated questionnaires at first and second examinations. In particular, the Bristol Female Lower Urinary Tract Symptoms questionnaire was used to evaluate urinary symptoms, the Knowles–Eccersley–Scott–Symptom questionnaire to assess the presence of constipation, and the Female Sexual Function Index to investigate sexual function. Study outcomes were the comparisons among groups in terms of differences in actual changes in median of questionnaire scores between first and second examinations. Results: Thirty women (17 in the experimental group and 13 in the control group) completed the study. No significant differences were found between the two groups regarding urinary, bowel, and sexual functions, although women in the experimental group showed a tendency towards an improvement in constipation symptoms. Conclusion: In women with DIE, PFP does not appear to affect urinary, bowel, and sexual functions. Therefore, despite the improvement in superficial dyspareunia, chronic pelvic pain, and PFM relaxation with high treatment satisfaction, women should be informed about the unclear impact of PFP on urinary, bowel, and sexual functions. Larger studies are necessary to further investigate the impact of PFP on these functions.
Brittle Crack Arrest Temperature Estimation Method Utilizing a Small-Scale Test with a Thick Steel Plate for Shipbuilding
Authors: An Gyubaek , Park Jeongung , Seong Daehee , Seo Junseok
Published: December 2023

As the shipbuilding industry has emerged from an extended recession, orders for high-value-added ships, such as LNG and ultra-large container ships, are increasing. For ultra-large container ships, high-strength, thick materials are applied. Because the possibility of brittle fracture increases owing to the application of thick steel plates, the related regulations of the International Association of Classification Societies have been strengthened to prevent brittle fracture. To secure brittle fracture stability, it is necessary to secure crack arrest toughness (Kca) through large ESSO experiments or to secure a crack arrest temperature (CAT) value. Because large-scale experiments require considerable costs and efforts, efforts have increased to examine brittle fracture stability through small-scale tests. In the present study, a technology was developed to predict CAT with small specimens. The CAT prediction formula developed with small specimens makes it possible to accurately predict CAT using data obtained through large-scale experiments.
Multiscale Investigation of Microcracks and Grain Boundary Wetting in Press-Hardened Galvanized 20MnB8 Steel
Authors: Arndt Martin , Kürnsteiner Philipp , Truglas Tia , Duchoslav Jiri , Hingerl Kurt , Stifter David , Commenda Christian , Haslmayr Johannes , Kolnberger Siegfried , Faderl Josef , Groiss Heiko
Published: December 2023

Grain boundary wetting as a preliminary stage for zinc-induced grain boundary weakening and embrittlement in a Zn-coated press-hardened 20MnB8 steel was analyzed using electron backscatter diffraction, Auger electron spectroscopy, energy dispersive X-ray analysis, atom probe tomography and transmission electron microscopy. Microcracks at prior austenite grain boundaries were observed. Structures that developed after microcrack formation were identified: for example, Zn/Fe intermetallic phases with grain sizes smaller than 100 nm were present at the crack surfaces and the wedge-shaped crack tips. An electrolytically coated reference sample that underwent the same heat treatment as the press-hardened material but without the application of tensile stress was investigated in order to find the initial cause of the microcracks. On this sample, Zn, in the order of one atomic layer, was found along prior austenite grain boundaries several micrometers away from the actual Zn/Fe phases in the coating. The resulting grain boundary weakening with the Zn wetting of prior austenitic grain boundaries during austenitization and/or hot forming is a necessary precondition for microcrack formation.
A Comparative Study on the Effect of Substrate Structure on Electrochemical Performance and Stability of Electrodeposited Platinum and Iridium Oxide Coatings for Neural Electrodes
Authors: Li Linze , Jiang Changqing , Li Luming
Published: December 2023

Implantable electrodes are crucial for stimulation safety and recording quality of neuronal activity. To enhance their electrochemical performance, electrodeposited nanostructured platinum (nanoPt) and iridium oxide (IrOx) have been proposed due to their advantages of in situ deposition and ease of processing. However, their unstable adhesion has been a challenge in practical applications. This study investigated the electrochemical performance and stability of nanoPt and IrOx coatings on hierarchical platinum-iridium (Pt-Ir) substrates prepared by femtosecond laser, compared with the coatings on smooth Pt-Ir substrates. Ultrasonic testing, agarose gel testing, and cyclic voltammetry (CV) testing were used to evaluate the coatings’ stability. Results showed that the hierarchical Pt-Ir substrate significantly enhanced the charge-storage capacity of electrodes with both coatings to more than 330 mC/cm2, which was over 75 times that of the smooth Pt-Ir electrode. The hierarchical substrate could also reduce the cracking of nanoPt coatings after ultrasonic, agarose gel and CV testing. Although some shedding was observed in the IrOx coating on the hierarchical substrate after one hour of sonication, it showed good stability in the agarose gel and CV tests. Stable nanoPt and IrOx coatings may not only improve the electrochemical performance but also benefit the function of neurobiochemical detection.
Analysis of the Operation Mechanism of Superjunction in RC-IGBT and a Novel Snapback-Free Partial Schottky Collector Superjunction RC-IGBT
Authors: Yuan Song , Li Yichong , Hou Min , Jiang Xi , Gong Xiaowu , Hao Yue
Published: December 2023

This paper explores the operation mechanism of the superjunction structure in RC-IGBTs based on carrier distribution and analyzes the advantages and challenges associated with its application in RC-IGBTs for the first time. A Partial Schottky Collector Superjunction Reverse Conduction IGBT (PSC-SJ-RC-IGBT) is proposed to address these issues. The new structure eliminates the snapback phenomenon. Furthermore, by leveraging the unipolar conduction of the Schottky diode and its fast turn-off characteristics, the proposed device significantly reduces the turn-off power consumption and reverse recovery charge. With medium pillar doping concentration, the turn-off loss of the PSC-SJ-RC-IGBT decreases by 54.1% compared to conventional superjunction RC-IGBT, while the reverse recovery charge is reduced by 52.6%.
A Novel Flexible Liquid Metal Microheater with a Textured Structure
Authors: Li Yuqing , Zhang Huimin , Ye Zi , Liu Mingyang , Liu Wei , Li Zhenming , Gui Lin
Published: December 2023

In this paper, we propose a novel liquid metal microheater utilizing a textured structure. This microheater effectively solves the problem of the liquid metal in the PDMS flow channel fracturing at a certain temperature and significantly increases the maximum operating temperature that can be achieved by the current liquid metal microheater. Experimental results demonstrate that this new structured microheater can achieve a maximum operating temperature exceeding 300 °C. To explain the performance improvement and the reasons behind liquid metal fracture, corresponding experiments were conducted, and explanations were provided based on the experimental results. Subsequently, we verified the mechanical flexibility of the microheater and found that it exhibits excellent tensile and bending resistance. Finally, utilizing its good mechanical flexibility, the microheater was successfully attached to the side wall of a cup, resulting in the boiling of water.
Fabricating Ultra-Narrow Precision Slit Structures with Periodically Reducing Current Over-Growth Electroforming
Authors: Yang Xiaohong , Zhang Xinmin , Ming Pingmei , Li Yuntao , Wang Wei , Zhang Yunyan , Li Zongbin , Li Lunxu , Xiao Youping , Guo Xiaoyi , Yang Zheng
Published: December 2023

An ultra-narrow precision slit with a width of less than ten micrometers is the key structure of some optical components, but the fabrication of these structures is still very difficult to accomplish. To fabricate these slits, this paper proposed a periodically reducing current over-growth electroforming process. In the periodically reducing current over-growth electroforming, the electric current applied to the electrodeposition process is periodically stepped down rather than being constant. Simulations and experimentation studies were carried out to verify the feasibility of the proposed process, and further optimization of process parameters was implemented experimentally to achieve the desired ultra-narrow precision slits. The current values were: I1=Iinitial, I2=0.75Iinitial at Qc=0.5Qt, I3=0.5Iinitial at Qc=0.75Qt,respectively. It was shown that, compared with conventional constant current over-growth electroforming, the proposed process can significantly improve the surface quality and geometrical accuracy of the fabricated slits and can markedly enhance the achievement of the formed ultra-narrow slits. With the proposed process, slits with a width of down to 5 ± 0.1 μm and a surface roughness of less than 62.8 nm can be easily achieved. This can improve the determination sensitivity and linear range of the calibration curves of spectral imagers and food and chemical analysis instruments. Periodically reducing current over-growth electroforming is effective and advantageous in fabricating ultra-narrow precision slits.