bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual single-atom sites coupled with graphene-encapsulated core–shell Fe–Cu nanoalloy for boosting the oxygen reduction reaction
Authors: Srinivas Katam , Chen Zhuo , Chen Anran , Huang He , Yang Chengtao , Wang Fei , Zhu Ming-qiang , Chen Yuanfu
Published: September 2024

The strategic integration of Cu–Nx sites and graphene-encapsulated Fe–Cu core–shell nanoalloys near Fe–Nx sites significantly enhances the performance of Fe single-atom catalysts for the oxygen reduction reaction.
Cost-effective synthesis of rGO/CeNiO3 perovskite nanocomposites for enhanced and stable supercapacitors and oxygen evolution reaction catalysts
Authors: Kumaresan Lakshmanan , Palanisamy Govindasamy , Lee Jintae
Published: September 2024

We have successfully developed a low-cost and highly stable rGO/CeNiO3 electrode for excellent bifunctional performance for both supercapacitor applications and the oxygen evolution reaction.
Constructing a zero leak landfill cell
Authors: Gilson Abigail , Brechko Nick
Published: September 2024

Engineered landfill barriers are the last line of defence in protecting precious groundwater resources from contamination. A landfill cell without any leaks at the conclusion of construction is the exception rather than the rule. From design to materials testing to installation practices and contractor care, all of these elements contribute to both the short and long-term integrity of the lining system. Electrical leak location (ELL) methods can be used to detect leaks in installed landfill cells after construction so that leaks can be repaired before a landfill cell begins filling operations. However, the thorough testing of landfill cells using ELL can be complicated by their complex configuration. The dipole method, employed after cover material placement, requires electrical isolation of the cover material, which is difficult to achieve with a landfill expansion cell configuration. Additionally, employing only this type of testing can leave the tie-in area untested, which is a critical area prone to damage. This paper provides solutions for complete landfill expansion cell testing, including a relatively new testing methodology (ASTM D8265, [1]), which provides protocol for verifying that a geomembrane has been successfully installed with no leaks. A case study is included to show how ASTM D8265 can be used to provide documentation of a zero-leak condition of a landfill cell after construction. Common elements of design, geomembrane installation, and quality assurance are discussed in order to provide a road map of how to reach a zero-leak condition at the end of a landfill expansion cell construction project. This paper can be used as a guide to constructing a zero-leak landfill cell using state-of-the art construction practices and ELL testing methodologies.
When field seam test results sail, yet laboratory test results pass: A practical approach to understanding why
Authors: Eichelberger Cristopher , Kamp Ryan , Koerner George
Published: September 2024

A standard quality control (QC) and quality assurance (QA) plan during installation of an unreinforced polyethylene geomembrane often requires destructive testing of the production welded seams at regular intervals. This testing is different from “trial weld testing.” Prior to welding of the seams, within the project footprint, a “trial weld” is fabricated on site as a proficiency test. The procedure utilizes project specific geomembrane material, environmental conditions, welding technician and equipment intended to perform the seaming of geomembrane installed as part of the containment system. There are cases where on-site trial welds become difficult to pass, even when experienced crews, quality equipment and materials are present. The difficulty can lead to a scenario where trial welds fail and destructive seam tests pass when sent to a 3rd party lab for testing, (this is a nightmare for geomembrane installers). Variables are numerous and often difficult to identify between these two different testing scenarios. However, this paper will show results and insightful data that will give rationale for the discrepancy.
Comparative life cycle assessment study for erosion control application with conventional shotcrete and geomat solutions
Authors: Ferrara M.L. , Jayakrishnan P.V.
Published: September 2024

Geosynthetic products are used more frequently in civil and environmental engineering applications due to their technological, commercial, and sustainable advantages. However, a quantitative analysis of the sustainability benefits of geosynthetics compared to traditional solutions is rarely conducted in real projects. Traditional engineering design primarily considers function, cost, and safety, while sustainable engineering design also takes into account the impact the design will have on society and the environment. To ensure sustainability in engineering, designers need quantitative tools to evaluate the metrics that can be applied in the design process. One such tool is life cycle assessment (LCA) for evaluating sustainability in engineering designs. The use of polymeric materials in construction projects may not immediately appear to have environmental benefits. However, geosynthetics can significantly reduce the use of other natural construction materials, which more than compensates for any negative impact. Additionally, geosynthetic solutions can reduce global warming potential due to their reduced carbon emissions. Although this topic is less widely discussed outside the geosynthetics industry, it is important for any construction project. Geosynthetic applications reduce carbon emissions and lower non-renewable energy consumption, ozone layer depletion, acidification, and eutrophication. This paper presents the results of a detailed comparative LCA study between a geomat and a traditional shotcrete-based erosion control solution.
The role of geosynthetic materials and vegetation on slope erosional control: Results of scale model tests
Authors: Olinic Tatiana , Olinic Ernest Daniel
Published: September 2024

Geosynthetic materials for erosion control have the potential to significantly reduce the soil loss and to ensure the shallow stability of slopes. The paper presents the results of a scale model tests of a 2:3 (V:H) slope made from a very erodible soil, a sandy soil without and with 5 cm of topsoil, with and without vegetation, without and with different types of geosynthetics for erosional control. The slope models were subjected to heavy rainfall using a rainfall simulator. Results of the study show that the geosynthetics and vegetation generates a delay in the erosion process caused by the raindrops. Another result highlighted in this paper is the fact that the roots system improves the soil shear strength of the upper soil mass.
Fluorescent microspheres in particle migration studies during geotextile dewatering: Proof of concept
Authors: Karamizadeh Narges , Huang Yan Nan , Lake Craig , Jamieson Rob
Published: September 2024

Understanding the mobility of small particles in geotextile dewatering applications is important when considering highly toxic sediments containing dioxins and furans. These contaminants are often strongly associated with organic matter that are colloidal in size. Microspheres have been used in the soil science research community for tracking the mobility of colloids through porous media for various applications (e.g., bacteria, virus). In this paper, the use of microspheres as a surrogate for small particles (2μm) in geotextile dewatering tests is investigate. Establishment of a reliable and repeatable method for microsphere visualization with a microscope is presented, both for detection and quantification. A simple geotextile dewatering test is conducted in which a soil filter cake is established and the microspheres are passed through the filter cake, followed by the passing of distilled water. It is shown that the microspheres in the effluent can help assist in better understanding the transport of small particles during dewatering which can help us better understand risk of particle transport in these types of tests.
Effect of wet and dry cycles on lighter bentonite-polymer geosynthetic clay liners
Authors: Stark Benjamin M. , Zhao Hanrui , Tian Kuo
Published: September 2024

This study evaluated the hydraulic conductivity (K) of lighter bentonitepolymer (B-P) geosynthetic clay liners (GCLs) subjected to wet-dry cycles which simulated seasonal conditions on a GCL installed in a landfill cover system. Lighter bentonite-polymer composite (B-P) GCLs are manufactured with a lower mass per unit area of sodium bentonite (Na-B) (approximately 2.9 kg/m2) than conventional Na-B GCLs (approximately ≥ 3.6 kg/m2) which can reduce the transportation and installation costs compared to conventional Na-B GCLs. Hydraulic conductivity tests on lighter B-P GCL and Na-B GCL were conducted with a synthetic soil porewater leachate to represent wet season conditions on a landfill cover. Between hydraulic conductivity tests, GCL samples were placed in sealed chambers with a relative humidity of 75% until the water content of the specimens decreased to 55%, which represented dry season conditions of a GCL under a geomembrane in a cover system. Slight increases of the hydraulic conductivity were measured for both the Na-B and lighter B-P GCLs. After 5 wet-dry cycles K of the Na-B GCL increased from 3.1 x 10-12 m/s to 8.3 x 10-12 m/s, and K of the lighter B-P GCL increased from 1.6 x 10-12 m/s to 8.3 x 10-12 m/s.
Using an engineered turf cover to support PV solar systems on landfills
Authors: Zhu Ming , Hughes Kenneth
Published: September 2024

Using landfills as solar sites saves natural lands from destruction. The large space of a closed landfill usually has limited redevelopment options due to restricted site access and long-term operation and maintenance requirements. A solar farm built on top of a closed landfill can generate additional revenue to offset post-closure maintenance costs and transform the otherwise undevelopable site into a renewal energy asset. A new solution has been developed in recent years to use an engineered turf cover to close a landfill, which serves as a foundation to support a low-profile photovoltaic (PV) solar power generation system. Case studies are presented to demonstrate field installation and performance of this new landfill closure and solar development solution.
Exhumation of HDPE geomembranes exposed to the weather for 10 years in a gold mining tailing
Authors: Urashima Beatriz , Santos Renato , Ferreira Lucas , Inui Toru , Urashima Denise
Published: September 2024

The durability study of a high-density polyethylene (HDPE) geomembrane that has been acting as a fluid barrier for 10 years in a gold mining dam/reservoir in Brazil was evaluated. The system stores waste considered hazardous, according to Brazilian legislation, with an average pH of 8 and presence of a cyanide solution. Samples exhumed after 10 years of service were exposed to the following three conditions: 1- only the weather; 2- contact with waste and exposure to the weather; 3- with field seams in contact with the tailings and exposure to the weather. Tensile strength, deformation under traction, tear resistance, puncture resistance and stresscracking tests were carried out. With the use of statistical tools, the results obtained were compared with the GM13 standard. Through the results analysed, it was not possible to observe significant losses in the geomembrane's resistances or a significant increase in its tensile deformation. It was observed the geomembrane did not present significant alteration in 10 years of service, with stress crack exception. The geomembrane may be able to continue to perform the function for which it was designed. It is necessary to carry out additional tests and monitor the system to understand whether or not its low performance in stress crack test is affecting the flow barrier function.
Root cause failure assessment of a water retention reservoir at a mining industry Site
Authors: Wall Dean , Kerry Rowe R.
Published: September 2024

This paper reports on an investigation into the failure of a double HDPE geomembrane lined retention reservoir constructed in 2018 that failed in 2021, only 3 years after construction. Several technical and non-technical factors contributed to the failure, and these are examined systematically. The primary failure occurred at the outlet pipe penetration, where the design detail had been modified due to constructability issues. Several administrative failures were also identified during the investigation, the most significant of which was the absence of a comprehensive construction report with a concluding statement from the engineer of record verifying the structure was constructed in accordance with the design and specifications and is fit for purpose. The failure highlights the need to better integrate design and construction teams and to keep impeccable records of all technical decisions.
Numerical modeling for mining dam cover infiltration design with geosynthetics: A trade off study
Authors: Martins Paula , Prinz Gabriela
Published: September 2024

In the mining dam closure project, depending on the classification of the tailings, cover systems are used to reduce precipitation infiltration over time, avoiding future environmental impacts associated with metal leaching. Furthermore, reduced infiltration promotes reservoir drainage and therefore improved geotechnical stability. The covering system can be built from different materials, natural or synthetic, or even using waste itself. The main objective of this study is to present the results as a trade-off study of a one-dimensional modeling performed considering 3 configurations of geosynthetic covers, using the SOFTWARE SEEP/W emphasizing the importance and impact of the presence of geosynthetics. Since numerical models constitute an essential tool in the development of engineering projects, computational numerical modeling was carried out using Brazilian climatic parameters from the National Institute of Meteorology in conventional and automatic stations, and historical geotechnical parameters for a structure located in the state of Minas Gerais. Gerais (Brazil). For the comparison of the cover configurations, the thickness and type of the geosynthetic were varied. The results emphasize the importance of studying numerical modeling in the pre-closure design phase, to define a viable, economical and sustainable coverage, and contribute to the use of geosynthetics in this type of application.
Ca-bentonite/polymer blends to compose GCLs for effective containment of mining leachates
Authors: Silva Debora T. V. , Correia Natalia S. , Souza Mauro A. , Portelinha Fernando H. M.
Published: September 2024

This study investigates the swelling potential of blends of a Brazilian sodium-activated calcium bentonite with linear structure polymers and a cross-linked structure polymer in contact with aggressive mining solutions (sodium hydroxide, calcium chloride, simulated bauxite liquor, copper tailing and gold tailing leachates). Results showed that the polymer addition contributed to the swelling of the bentonite under aggressive solutions. The effectiveness of the polymers varied with the permeant liquid and concentration. Sodium Polyacrylate and Carboxymethyl Cellulose proved the most effectiveness in bentonite swelling capacity. Research presents valuable insights into the chemical compatibility of bentonitepolymer blends when exposed to aggressive liquids.
Degradation behavior of stressed polyester reinforcing products under alkaline conditions embedded in eluates and soils
Authors: Detert Oliver , Sadegh-Azar Parviz , Strahberger Matthias
Published: September 2024

The use of geosynthetic reinforcements in different applications has been proven over the last decades to be a very beneficial and valid technique. For a safe design of such structures the long-term behavior and especially the available resistant tensile force over the time under variable boundary conditions, such as temperature, chemical influences or loading conditions, has to be well known and understood. The known effects, which lead to a reduction in tensile strength, are considered in the design by applying so called reduction factors. So far, those reduction factors are determined separately without considering a possible interdependency. Latest research results are indicating that this can lead to major misjudgements. The main mechanism of the chemical degradation of polyester in high alkaline environment is the so called alkaline or “external” hydrolyses. In contrast to the internal hydrolyses, which provokes an evenly distributed, very slow degradation of the whole cross-section of the synthetic material, the external degradation generates a much faster “surface corrosion” with creation of fissures or cracks. If this does occur while the material is loaded, the fissures are widened, and their propagation are dramatically accelerated. The understanding and consideration of chemical degradation under mechanical stress is from crucial importance. This research will present results for products made of PET with different production technologies, where above-described mechanism has been investigated in more detail and conclude with a recommendation, how to proceed based on those findings. Tests have been conducted with samples embedded in eluate as well as in partially and fully saturated soils.
Unraveling the Interplay of 5-hydroxytryptamine-3 and
N-methyl-d-aspartate Receptors in Seizure Susceptibility
Authors: Jahanabadi Samane , Madvar Mohammadreza Riahi
Published: September 2024

Background Epilepsy, a prevalent neurological disorder characterized by
recurrent seizures, presents significant challenges in treatment and management.
This study aimed to evaluate the effect of tropisetron, a selective 5-HT3
receptor antagonist on pentylenetetrazole (PTZ) – induced seizure in mice by
exploring the potential role of the NMDA receptor and inflammatory
responses.

Methods For this purpose, seizures were induced by intravenous PTZ
infusion. Tropisetron at 1-, 2-, 3-, 5-, 10- mg/kg were administered
intraperitoneally 30 minutes before PTZ. To evaluate probable role of NMDA
signaling, selective NMDAR antagonists, ketamine and MK-801, were injected
15 minutes before tropisetron. Also, TNF-α level of hippocampus were measured
following administration of mentioned drugs in mice.

Results Our results demonstrate that tropisetron displayed a
dose-dependent impact on seizure threshold, with certain doses (5 and 10 mg/kg)
exhibiting anticonvulsant properties. In addition, the noncompetitive NMDAR
antagonists, ketamine (1 mg/kg) and MK-801 (0.5 mg/kg), at doses that had no
effect on seizure threshold, augmented the anticonvulsant effect of tropisetron
(3 mg/kg). Also, tropisetron led to a reduction in hippocampal TNF-α levels,
indicating its anti-inflammatory potential independent of 5-HT receptor
activity.

Conclusion In conclusion, we demonstrated that the anticonvulsant effect
of tropisetron is mediated by the inhibition of NMDA receptors and a decline in
hippocampal TNF-α level. These findings highlight a potential connection between
5-HT3 and NMDA receptors in the pharmacological treatment of inflammatory
diseases, such as seizure, warranting further investigation into their combined
therapeutic effects.
Efficacy of Subperiosteal Drains in Chronic Subdural Hematoma: A Prospective Randomized Single-Center Study
Authors: Bozhkov Yavor , Feulner Julian , Buchfelder Michael , Kleiss Max , Brandner Sebastian , Kinfe Thomas M.
Published: September 2024

Background Chronic subdural hematomas (cSDHs) are most frequently treated by evacuation via a burr-hole craniostomy procedure. Subperiosteal drains have been introduced as alternatives to subdural ones, but only a few prospective studies have explored their efficacy. Thus, a prospective randomized trial was designed to assess their use.

Methods The study enrolled patients with newly diagnosed surgically amenable cSDH. These patients were randomized into two groups. The first group underwent cSDH evacuation via a single burr hole craniostomy procedure, followed by placement of a subperiosteal drain; the second group underwent the identical procedure without drain placement. Patient demographics, drain volumes, duration of drainage, cSDH recurrence, and postoperative outcomes were recorded.

Results Eighty-eight patients presenting with cSDH (12 with bilateral cSDHs) from a total of 100 surgical cases were enrolled. Nine patients (1 bilateral) were lost to follow-up. Of all remaining 90 procedures, 37 were carried out with drain placement and the remaining 53 without drain placement. There were five recurrent cases (13.5%) in the drain placement group and 17 (32.1%) in the group without drain placement. This resulted in a statistical significance (odds ratio [OR]: 0.33; p < 0.05) favoring the use of a drain.

Conclusion Subperiosteal drain placement can be used safely and effectively to treat cSDH in conjunction with a burr-hole craniostomy procedure, significantly reducing the rate of recurrence without any additional disadvantages.
Early-Onset Adjacent Vertebral Fractures after Balloon Kyphoplasty and SpineJack Kyphoplasty for the Management of Single-Level Thoracolumbar Vertebral Compression Fractures
Authors: Chung Ming-Hsuan , Yang Yun-Ju , Wu Yi-Chieh , Chen Guann-Juh , Ju Da-Tong , Chou Kuan-Nien
Published: September 2024

Background The aim of this study was to evaluate the risk factors contributing to early-onset adjacent level fractures (ALFs) occurring within 1 month following either balloon kyphoplasty (BKP) or SpineJack kyphoplasty (SJ) for the treatment of thoracolumbar vertebral compression fractures (TLVCFs).

Methods This retrospective analysis enrolled patients with single-level TLVCFs (T11–L2) who underwent either BKP or SJ between July 2013 and June 2019. We recorded the ALF occurrences within 1 month. Age, osteoporosis, severity and shape of TLVCFs, and surgical type were compared between patients with and without early-onset ALFs.

Results Altogether, 106 TLVCF patients were enrolled, comprising 64 BKP and 42 SJ cases. We observed 19 early-onset ALFs, with 9 and 10 cases in the BKP and SJ, respectively. Patients with early-onset ALFs have significantly more severe TLCVFs (severe vs. mild, 25 vs. 0%, p = 0.055), and wedge-shaped TLVCFs (26.47 vs. 2.63%, p = 0.002), older age (81.05 vs. 73.34 years, p < 0.001), and kyphoplasty performed within 1 month are risk factors for early-onset ALFs (26.92 vs. 9.26%, p = 0.018). Univariable analysis showed that kyphoplasty timing within 1 month (odds ratio [OR]: 0.193; p = 0.008), wedge-shaped TLVCFs (OR: 5.358; p = 0.036), and advanced age (OR: 1.119; p = 0.001) are significant risk factors for early-onset ALFs.

Conclusions The occurrence rate of early-onset ALFs between BKP or SJ techniques in treating TLVCFs does not differ. Preoperative wedge-shaped TLVCFs, advanced age, and early treatment within 1 month are the risk factors for early-onset ALFs following kyphoplasty for TLVCFs.
Embolization of Bleeding Ileal Varices post Adnexal Biopsy in Liver Cirrhosis without Gastroesophageal Varices
Authors: Wagle Suhas D. , Munde Yadav , Vaze Smita Kori , Mankeshwar Tejas
Published: September 2024

Bleeding ileal varices are rare in liver cirrhosis, where the gastroesophageal varices frequently accompany ectopic varices. Small bowel varices usually develop in patients with a history of abdominal surgery. We report a case of bleeding ileal varices without accompanying gastroesophageal varices, managed by percutaneous embolization, in a case of liver cirrhosis with no history of laparotomy. Computed tomography–guided percutaneous adnexal biopsy had been undertaken a year before the onset of bleeding.
Frequencies of Human Leukocyte Antigen Alleles in Turkish Children with Kawasaki Disease
Authors: Teke Türkan Aydın , Tan Çağman , Aydın Zeynep Gökçe Gayretli , Kaman Ayşe , Özbek Begüm , Öz Fatma Nur , Çağdaş Deniz , Tanır Gönül , Tezcan İlhan
Published: September 2024

Objective Kawasaki disease (KD) is an acute systemic vasculitis that is one of the major causes of acquired heart disease especially in young children. The pathogenesis of KD is still unclear. The increased incidence of the disease among Japanese children and siblings of affected patients suggests a genetic component to KD susceptibility. Several reports have studied human leukocyte antigen (HLA) polymorphisms in different populations with KD and found various results. In the present study, we aimed to evaluate the association of HLA-A, -B, -C, -DRB1, and -DQB1 allele frequencies in Turkish children with KD.

Methods The study was conducted between January 2016 and February 2018. HLA Class I (A, B, and C) and Class II (DRB1 and DQB1) alleles of patients and healthy controls were studied using the low-resolution DNA-based sequence-specific oligonucleotide method.

Results Fifty children with KD and 500 healthy controls were included in this study. In the analysis of HLA-A, HLA-B, HLA-C, and HLA-DRB1 alleles, no statistical difference was found in the frequency of alleles between the patients with KD and the control group. However, a significantly lower frequency of the HLA-DQB1*03 allele was observed in the KD group than in the control group (p < 0.001, odds ratio [OR]: 0.29, 95% confidence interval [CI]: 0.15–0.55). When the patients with KD were divided into two subgroups with or without coronary artery lesions (CALs), the frequency of the HLA-DQB1*03 allele was also found lower in the KD group with CALs than the KD group without CALs (p = 0.008, OR: 0.19, 95% CI: 0.05–0.68).

Conclusion The study may guide future studies on HLA-DQB1*03 whether it is a protective allele for KD and CALs in Turkish children.
Mathematical analysis of the Wiener processes with time-delayed feedback
Authors: Kobayashi Miki U. , Takehara Kohta , Ando Hiroyasu , Yamada Michio
Published: September 2024

It is known that time delays generally make a system unstable. However, it is numerically observed that the diffusion coefficients of the Wiener processes with time-delayed feedback decrease while increasing the time delay τ. In particular, the decay of the diffusion coefficients with the form (11+τ)2 has been confirmed by numerical simulations [Ando et al., Phys. Rev. E 96, 012148 (2017)]. In this paper, we present two analytical derivations for the relation (11+τ)2 by dynamical system approaches using the Laplace transform and stochastic differential equations.
Numerical simulation and experimental study of the dynamic characteristics of a gas turbine rotor system with beam sea and head sea excitation
Authors: Zhang Xin , Liu YongBao , Wang Qiang , Xing ZhiKai , Li Mo
Published: September 2024

Vibration analysis is crucial for studying rotor dynamics. The gas turbine rotor system is subjected to complex alternating loads during navigation, resulting in vibrations transmitted to the bearings that alter the system’s dynamic characteristics. Based on the similarity law of the wave resistance test, a hull model was established. Beam sea and head sea tests were conducted in the towing pool to measure the acceleration response at the key positions. A finite element model of the turbine rotor system was established, and the test data were imported into the model after wavelet noise reduction and resampling to calculate the vibration response at the front and rear bearing points. The vibration responses transmitted to different locations and directions caused by beam sea and head sea conditions were analyzed. A comparison and analysis were conducted on the acceleration responses in various locations and directions under beam sea or head sea conditions. The equivalent von Mises stress distribution of the gas turbine rotor system under beam sea and head sea loads was obtained. The vibration transfer model was verified for accuracy and can be used to quickly analyze the vibration response of bearings under wave load transfer. This study provides a theoretical basis and reference for enhancing the stability of the gas turbine rotor system.
Hunting down the elusive cytosolic-DNA sensor
Authors: Mathis Diane
Published: September 2024

The 2024 Albert Lasker Basic Medical Research Award was attributed to Zhijian (James) Chen for “the discovery of the cGAS enzyme that senses foreign and self DNA, solving the mystery of how DNA stimulates immune and inflammatory responses.” Bringing to bear an ingenious in vitro complementation system, an astute insight, and superlative biochemistry, Chen and colleagues identified cGAS (cGAMP synthase) as both the molecule that perceives cytosolic DNA in infected, stressed, or dying cells and the enzyme that catalyzes the synthesis of cGAMP (cyclic GMP-AMP), a critical second messenger along the route to inflammatory cytokine production. These findings cleared up the reigning confusion surrounding a major mechanism of inciting the innate immune system, with therapeutic implications for fighting infections, containing tumors, and extinguishing autoimmune and inflammatory diseases.
Inhibition of hTERT/telomerase/telomere mediates therapeutic efficacy of osimertinib in EGFR mutant lung cancer
Authors: Chen Zhen , Vallega Karin A. , Wang Dongsheng , Quan Zihan , Fan Songqing , Wang Qiming , Leal Ticiana , Ramalingam Suresh S. , Sun Shi-Yong
Published: September 2024

The inevitable acquired resistance to osimertinib (AZD9291), an FDA-approved third-generation EGFR tyrosine kinase inhibitor (EGFR-TKI) for the treatment of patients with advanced non-small cell lung cancer (NSCLC) harboring EGFR activating or T790M resistant mutations, limits its long-term clinical benefit. Telomere maintenance via telomerase reactivation is linked to uncontrolled cell growth and is a cancer hallmark and an attractive cancer therapeutic target. Our effort toward understanding the action mechanisms, including resistance mechanisms, of osimertinib has led to the identification of a novel and critical role in maintaining c-Myc–dependent downregulation of hTERT, a catalytic subunit of telomerase, and subsequent inhibition of telomerase/telomere and induction of telomere dysfunction in mediating therapeutic efficacy of osimertinib. Consequently, osimertinib combined with the telomere inhibitor, 6-Thio-dG, which is currently tested in a phase II trial, effectively inhibited the growth of osimertinib-resistant tumors, regressed EGFRm NSCLC patient-derived xenografts, and delayed the emergence of acquired resistance to osimertinib, warranting clinical validation of this strategy to manage osimertinib acquired resistance.
Carleman estimates for space semi-discrete approximations of one-dimensional stochastic parabolic equation and its applications
Authors: Wu Bin , Wang Ying , Wang Zewen
Published: September 2024

In this paper, we study discrete Carleman estimates for space semi-discrete approximations of one-dimensional stochastic parabolic equation. We then apply these Carleman estimates to investigate two inverse problems for the space semi-discrete stochastic parabolic equations, including a discrete inverse random source problem and a discrete Cauchy problem. We firstly establish two Carleman estimates for a one-dimensional semi-discrete stochastic parabolic equation, one for homogeneous boundary and the other for non-homogeneous boundary. Then we apply these two estimates separately to derive two stability results. The first one is the Lipschitz stability for the discrete inverse random source problem. The second one is the Hölder stability for the discrete Cauchy problem.
Analysis and computation of an inverse source problem for the biharmonic wave equation
Authors: Chang Yan , Guo Yukun , Yin Tao , Zhao Yue
Published: September 2024

In this paper, we study the inverse source problem for the biharmonic wave equation. Mathematically, we characterize the radiating and non-radiating sources at a fixed wavenumber. We show that a general source can be decomposed into a radiating source and a non-radiating source. The radiating source can be uniquely determined by Dirichlet boundary measurements at a fixed wavenumber. Moreover, we derive a Lipschitz stability estimate for determining the radiating source. On the other hand, the non-radiating source does not produce any scattered fields outside the support of the source function. Numerically, we propose a novel source reconstruction method based on the Fourier series expansion by multi-wavenumber boundary measurements. The stability of the proposed method is analyzed and numerical experiments are presented to verify the accuracy and efficiency.
Polyaniline/graphitic carbon nitride/reduced graphene oxide ternary nanocomposite film for flexible thermoelectric application
Authors: Singh Manoj , Gautam Amish Kumar , Faraz Mohd , Khare Neeraj
Published: September 2024

The present study outlines the preparation of a ternary nanocomposite film comprising of polyaniline doped with camphor sulfonic acid (PANI), reduced graphene oxide (rGO), and graphitic carbon nitride (g-C3N4), and delves into its thermoelectric performance. PANI is known to possess high electrical conductivity (σ) and poor thermal conductivity (κ). However, its potential for thermoelectric applications is constrained by the low value of the Seebeck coefficient (S). The incorporation of g-C3N4 in PANI has been demonstrated to result in an improvement of the Seebeck coefficient. Furthermore, the addition of rGO to the PANI/g-C3N4 sample counteracts the decrease in electrical conductivity. The PANI/g-C3N4/rGO ternary nanocomposite film exhibits an enhanced Seebeck coefficient of ∼2.2 times when compared to the PANI sample. The Seebeck coefficient of the PANI/g-C3N4/rGO nanocomposite is enhanced by the energy filtering effect that occurs at the interfaces between g-C3N4/PANI and PANI/rGO. The π–π interaction between the PANI chains and rGO is responsible for the increased electrical conductivity resulting from the well-ordered polymer chain arrangement on the g-C3N4 and rGO surfaces. The ternary nanocomposite sample demonstrated a synergistic improvement in both electrical conductivity and Seebeck coefficient, resulting in a remarkable ∼4.6-fold increment in power factor and an ∼4.3-fold enhancement in the figure of merit (zT), as compared to the pristine PANI film.
Ag modified ZnO nanoflower gas sensitive sensor for selective detection of n-butanol
Authors: Wang Ai-Jing , Jin Zhen , Sun Yu-Ru , Zhou Shu-Hao , Li Jie
Published: September 2024

Ag modified ZnO nanoflowers were successfully prepared by sunlight induced solvent reduction method. The samples were characterized by x-ray diffractometer, field emission scanning electron microscope, transmission electron microscope and energy dispersive x-ray spectrum, and the results confirmed the presence of Ag nanoparticles on the ZnO nanoflower. The gas sensing performance of the materials was studied at different operating temperatures and different n-butanol concentrations. The results showed that the Ag modified ZnO nanoflower sensor responded to 50 ppm n-butanol up to 147.17 at 280 °C, and the Ag modified ZnO nanoflower sensor exhibited excellent repeatability, stability and response recovery time. In addition, different target gases were employed for the selectivity study of the Ag modified ZnO nanoflower. It can be found that the Ag modified ZnO nanoflower had good selectivity for n-butanol. The improved response of the Ag modified ZnO nanoflower sensor was attributed to the catalytic effect of Ag nanoparticles. The results indicate that the Ag modified ZnO nanoflower will become a very promising sensing material for n-butanol gas detection.
Minimal amenable subshift with full mean topological dimension
Authors: Yin Zhengyu , Xiao Zubiao
Published: September 2024

Let G be an infinite countable amenable group and P a polyhedron with the topological dimension

dim
⁡
(
P
)
<
∞

. We construct a minimal subshift (X, G) of

(

P
G

,
G
)

such that its mean topological dimension is equal to

dim
⁡
(
P
)

. This result answers the question of Dou (2017 Discrete Contin. Dyn. Syst.
37 1411–24). Moreover, it extends the work of Jin and Qiao (2023 arXiv:2102.10339) for

Z

-action.
Optical transmission and refraction at the atomic level
Authors: Riggs Peter J
Published: September 2024

The standard explanations for the phenomena of transmission and refraction of electromagnetic waves of optical wavelengths upon entering a transparent medium is in terms of the speed of the waves being altered. However, these phenomena are explicable without assuming that the speed of electromagnetic waves changes. The actual speed does not alter in various media but is customarily assumed to do so as this facilitates straight-forward calculations and allows easily understood explanations to be advanced. An underlying account of transmission and refraction at the level of individual atoms is presented in which the speed of electromagnetic waves remains constant.
Motion of a ball attached to a mass via a hole in a horizontal table
Authors: Cross Rod
Published: September 2024

Measurements are presented of the circular motion of a ball on a table attached to another ball by a length of thread via a hole in the table. It is a standard problem often assigned to students, but the experimental results differ from predictions.
Dosimetry at cellular level for the alpha-emitting radionuclides actinium-225, astatine-211 and radium-223 for bone metastasis cells from castration resistant prostate cancer
Authors: Oliveira-Silva Catherine C , Maillard Mateus S , Silva Raoni , Sá Lidia V
Published: September 2024

Objectives. The aim of this work is to evaluate energy deposition in the nucleus and cytoplasm in targeted alpha therapy of metastatic castration-resistant prostate cancer by modeling two cell lines, PC3 (osteolytic) and LNCaP C4-2 (osteoblastic), for actinium-225, astatine-211, and radium-223 and their progeny, using Monte Carlo simulations with the GATE/Geant4 code. Approach. We developed single cell and cell clusters models to Monte Carlo simulations, performed on the GATE platform version 9.3, with the GEANT4-DNA physics list emstandard_opt3_mixed_dna for At-211, Ac-225 and Ra-223 progenies. We considered three radionuclide distributions as a sources: the nucleus, the cytoplasm and the whole cell. Main results. When the nucleus was considered as a target, the S-values (N←N) calculated for At-211, Ac-225 and Ra-223 progenies were significantly higher, within 60%-90%, than S-values (N←Cy), demonstrating less influence of cytoplasm only internalization. When the cytoplasm was considering as a target, the S-values (Cy←Cy) calculated for At-211, Ac-225 and Ra-223 progeny were significantly higher, within 30%–90%, than the S-values (Cy←N). When no progeny migration occurs and for target nucleus , the cumulative S-values (N←N) calculated for At-211, Ac-225 and Ra-223 were significantly higher, within 50%–70%, than the S-values (N←N) computed for At-211, Ac-225, and Ra-223. Comparing the cumulative S-values, Ac-225 and Ra-223 therapies is more effective, in terms of deposited energy in a target, than that with At-211. Significance. The data presented in this research indicates that Ac-225 therapy may be the optimum choice due to the energy deposited in the nucleus, as long as the recoil effects and redistribution of progeny are understood. In contrast, At-211 is an alternative to avoid progeny migration. However, to completely analyze the efficacy of radionuclide therapy, other parameters must be considered, such as biological half-life, stability of the transport molecule, progeny migration, excretion pathways, and uptake in different organs.
RayStation/GATE Monte Carlo simulation framework for verification of proton therapy based on the 12N imaging
Authors: Ahmadi Ganjeh Zahra , Zapien-Campos Brian , Traneus Erik , Both Stefan , Dendooven Peter
Published: September 2024

Objective. 12N, having a half-life of 11 ms, is a highly effective positron emitter that can potentially provide near real-time feedback in proton therapy. There is currently no framework for comparing and validating positron emission imaging of 12N. This work describes the development and validation of a Monte Carlo (MC) framework to calculate the images of 12N, as well as long-lived isotopes, originating from activation by protons. Approach. The available dual-panel Biograph mCT PET scanner was modeled in GATE and validated by comparing the simulated sensitivity map with the measured one. The distributions of 12N and long-lived isotopes were calculated by RayStation and used as the input of GATE simulations. The RayStation/GATE combination was verified using proton beam irradiations of homogeneous phantoms. A 120 MeV pulsed pencil beam with 108 protons per pulse was used. Two-dimensional images were created from the GATE output and compared with the images based on the measurements and the 1D longitudinal projection of the full 2D image was used to calculate the 12N activity range. Main results. The simulated sensitivity in the center of the FoV (5.44%) agrees well with the measured one (5.41%). The simulated and measured 2D sensitivity maps agree in good detail. The relative difference between the measured and simulated positron activity range for both 12N and long-lived isotopes is less than 1%. The broadening of the 12N images relative to those of the longer-lived isotopes can be understood in terms of the large positron range of 12N. Significance. We developed and validated a MC framework based on RayStation/GATE to support the in-beam PET method for quality assurance of proton therapy. The inclusion of the very short-lived isotope 12N makes the framework useful for developing near real-time verification. This represents a significant step towards translating 12N real-time in vivo verification to the clinic.
Design and performance evaluation of a stick–slip actuator with Z-shaped beam and two-stage amplification system
Authors: Xu Dongmei , Liang Tenglin , Cao Chuqing , Wang Zhen , Zhao Zhiwei , Yu Simiao
Published: September 2024

In the domain of piezoelectric driving, actuators that utilize the stick–slip effect at high speeds and low frequency have garnered significant interest. This study presents an innovative linear piezoelectric actuator that integrates a two-stage amplification system with a Z-shaped beam mechanism. The designed actuator has good driving speed at low frequency while overcoming the disadvantage of such actuators requiring two flexible mechanisms to achieve reverse motion and poor reverse performance. The structure and scale of the actuator are explained and designed through theory and simulation. The experimental results demonstrate the prototype’s capability for bidirectional motion. Subjected to a 400 Hz and 140 V excitation, the maximum speed of the actuator is 12.88 mm s−1. The maximum load capacity is tested to be of 0.35 N. This research introduces a new approach for the design of high-speed bidirectional motion stick–slip piezoelectric actuators.
In situ assembly enabling adhesive-free bonding of large area electronic sensors to concrete for structural health monitoring
Authors: Ogunniyi Emmanuel , Liu Han , Downey Austin RJ , Laflamme Simon , Li Jian , Bennett Caroline , Collins William , Jo Hongki , Ziehl Paul
Published: September 2024

Cracks developed in concrete infrastructure are one of the primary mechanisms that degrade their structural integrity, which may result in structural failures. Previous research on soft elastomeric capacitors (SEC) has shown their viability for structural health monitoring of structural materials, including concrete, steel, and fiberglass composites. The SEC, or its derivative version with a corrugated geometry termed corrugated SEC or cSEC, is a parallel plate capacitor. Prior work demonstrated that it was possible to directly paint the electrode interfacing with the structural material onto the structure and adhere the rest of the pre-fabricated sensor onto the wet interface, thereby eliminating the need for a joining epoxy. This demonstration was conducted on steel and fiberglass. The study on concrete was left to future work as concrete exhibits a much rougher surface and structure/sensor capacitive coupling, causing a significant amplification in signal noise. This study advances structural health monitoring in concrete applications by investigating the in situ assembly of the SEC on concrete where the carbon black (CB)-based electrode plate of the cSEC is directly painted onto the concrete surface and serves as both the adhesive and electrode for the sensor. A series of free-vibration and compression tests were designed and conducted to evaluate the sensing performance of in situ assembled cSEC compared to that of an epoxy-bonded cSEC. Additionally, the bonding strength of the in situ assembled and epoxy-bonded cSEC is evaluated through a peel test. Results show good strain sensing capabilities of the in situ assembled SEC with an R
2 value of 0.986 and a resolution of 45

±
μ
ε

. Even though the epoxied cSEC demonstrated a higher bonding strength than the in situ assembled cSEC, the in situ assembled cSEC demonstrated adequate bonding strength for the application. This research contributes to the scientific understanding of sensor adhesion and opens avenues for practical applications in infrastructure monitoring, potentially leading to more resilient and sustainable urban environments.
Tunable thermoelectric superconducting heat pipe and diode
Authors: Antola F , Braggio A , De Simoni G , Giazotto F
Published: September 2024

Efficient heat management at cryogenic temperatures is crucial for superconducting quantum technologies. This study demonstrates the controlled manipulation of the heat flow and heat rectification through an asymmetric superconducting tunnel junction. The system exhibits a non-reciprocal behavior, developing a thermoelectric regime exclusively when the electrode with the larger gap is heated. This feature significantly boosts thermal rectification effectively classifying the device as a heat diode. At the same time when operating as a thermoelectric engine, the same device also functions as a heat pipe, expelling heat from the cryogenic environment, minimizing losses at the cold terminal. This dual functionality is inherently passive, and the performance of the heat pipe and the heat diode can be finely adjusted by modifying the external electrical load.
Experimental values for Nickel and Palladium in gas state resistivity limits
Authors: Rodríguez Prieto Gonzalo , Bilbao Luis E
Published: September 2024

Metals in various phases, including the gas state, can be obtained using a pulsed wire explosive system. If experimental system is properly configured, sufficient metal gas can be obtained to estimate the limits of its electrical resistivity in later phases of the discharge, complementing solid and liquid state measurements of the same parameter. This article presents for the first time those experimental limits for the metals Palladium and Nickel. Obtained values for Palladium maximum limits are in the range from 0.25 to 1.25 10−3 Ω · m, meanwhile Nickel obtained maximum ranges go from 0.3 to 1.5 10−3 Ω · m.