bluuebunny/crossref_metadata_2025 huggingface dataset:
Quality and Readability of Hearing Aid-Related Websites in English and Spanish
Authors: Willgruber Abbigayle , Kinealy Brian , Adkins David , Schuh Marissa , Shinn Jennifer B. , Cline Trey A. , Board Ryleigh , Hassan Zain , Bush Matthew
Published: December 2024

Objective To determine the readability and quality of both English and Spanish Web sites for the topic of hearing aids.

Study Design Cross-sectional Web site analysis.

Setting Various online search engines.

Methods The term “hearing aid” was queried across four popular search engines. The first resulted 75 English Web sites and first resulted 75 Spanish Web sites were extracted for data collection. Web sites that met the inclusion criteria were stratified by the presence of a Health on the Net Code (HONCode) certificate. Articles were then compiled to be independently reviewed by experts on hearing aids, using the DISCERN criteria, which allowed assessment of the quality of the Web sites. Readability was assessed by calculating the Flesch Reading Ease Score in English and the Fernandez Huerta Formula in Spanish. Readability and quality were both analyzed, comparing scores to their respective language and cross-comparing.

Results There were 37 English Web sites and 30 Spanish Web sites that met inclusion criteria. When analyzing readability, English Web sites were determined to be significantly more difficult to read (average = 55.37, standard deviation [SD] = 7.73, 95% confidence interval [CI] = 52.9–57.9) than the Spanish Web site counterparts (average = 58.64, SD = 5.26, 95% CI = 56.8–60.5, p = 0.035). For quality, Spanish Web sites (average = 38, SD = 9.7, 95% CI = 34.5–41.5) were determined to be of significantly higher quality than English Web sites (average = 32.16, SD = 10.60, 95% CI = 29.7–34.6). Additionally, there was a significant difference between the non-HONCode English Web sites versus the non-HONCode Spanish Web sites (p = 0.0081), signifying that Spanish non-HONCode certified Web sites were less reliable than non-HONCode certified English Web sites.

Discussion The present study highlights the importance and necessity of providing quality, readable materials to patients seeking information regarding hearing aids. This study shows that both English and Spanish Web sites are written at a level that is much higher than the American Medical Association (AMA)-recommended sixth-grade reading level, and no Web site included in this study fell at or below the AMA-recommended sixth-grade reading level. English and Spanish Web sites also lacked consistency and quality, as evidenced by their wide variability in DISCERN scores. Specifically, Hispanic patients are more likely to suffer long-term consequences of their health care due to low levels of health literacy. It is important to bridge this gap by providing adequate reading materials. It is especially important to provide evidence-based claims that are directly supported by experts in the field.
Hemorrhoidectomy Using the Harmonic Scalpel versus the Ferguson Technique
Authors: Aldawoodi Mustafa Abdullah , Rezqallah Raed Esttaifan
Published: December 2024

Introduction Hemorrhoidal disease is an anorectal condition commonly encountered in the clinical practice. Various instruments, such as circular staplers, harmonic scalpels, lasers, and bipolar electrothermal devices, are used in different modalities of hemorrhoidectomy in cases of high-grade hemorrhoids.

Objective T compare the results of hemorrhoidectomy using the Ferguson technique and the harmonic scalpel.

Materials and Methods The present is a randomized prospective study involving 60 patients submitted to hemorrhoidectomy from February 2022 to January 2024. The patients were randomly grouped: group I was composed of 30 patients who underwent the operation through the conventional Ferguson technique, and group II was composed of 30 patients submitted to hemorrhoidectomy with the use of the harmonic scalpel.

Results The demographic and clinical features of the patients in the two groups were identical. We found a significant difference in the mean operative time: for the Ferguson technique, it was of 21.9 ± 4.6 minutes, while for the harmonic scalpel, it was of 17.9 ± 3.1 minutes (p = 0.003). The mean postoperative pain scores on the Visual Analog Scale (VAS) were of 7.1 ± 1.2 points for group I, and of 6.5 ± 0.5 points for group II (p = 0.024). And the mean hospital stay was of 1.23 ± 2.1 days for group I, and of 1.03 ± 0.1 for group II (p = 0.023). No statistical significance was observed regarding the other parameters.

Conclusion Hemorrhoidectomy using the harmonic scalpel seems to be a superior approach to treat high-grade hemorrhoids; it has the advantage of reduced hospital stay, decreased postoperative pain, and shorter operative time.
Adjustable Phonatory PEEP to Treat Dysphonia: A Preliminary Investigation of Progressive Masked Voice Exercises (PMVE)
Authors: Frank Matthew K. , Sechtem Phillip R. , Garg Hina , Price Summer , Terry Camrin , Collins John R. , Castelli Dave
Published: December 2024

The Progressive Masked Voice Exercises (PMVE) with an innovative semioccluded ventilation mask fitted and adjustable positive end-expiratory pressure (PEEP) valve was evaluated. This study aimed to compare the effectiveness of the PMVE with the PEEP device and the Vocal Function Exercise (VFE) program on acoustic, auditory-perceptual, aerodynamic, and self-report measures. Twenty-five participants diagnosed with voice disorders met the criteria. Participants were randomly assigned to either the PMVE or the VFE group for a 6-week home therapy program. Pre- and post-data were analyzed with parametric and nonparametric statistics. Acoustic and aerodynamic measures showed no between-group or interaction group × time effects; however, a main effect of time was observed for all but one of the eight acoustic variables, indicating that both groups improved. Additional within-group analysis showed improvements in two of the eight variables for the PMVE program and four for the VFE program. No between-group differences were observed for the auditory-perceptual judgments using the GRBASI scale; however, the strain was improved for the VFE group. No differences in self-report measures were also seen, except for the VFE group. This study provides preliminary evidence for the PMVE therapy program. Further research is needed in large and diverse samples and clinical application is invited.
Association of Evening Eating with Sleep Quality and Insomnia among Adults in a Brazilian National Survey
Authors: Nunes Maria Eduarda Bezerra , dos Santos Caio Henrique Barros , Lima Márcia de Oliveira , Pedrosa Anny Kariny Pereira , de Menezes Risia Cristina Egito , Longo-Silva Giovana
Published: December 2024

Objective To examine the association of evening eating clock time, its elapsed time to the midpoint of sleep (TEM), consumption of caffeine and sugary foods, and reporting dinner as the largest meal with sleep quality indicators and insomnia.

Methods Participants (n = 2,050;18–65y) were part of population-based research, with virtual data collection. Logistic regression models were fitted to assess differences in the ORs(95%CI) of sleep duration < 7 hours, sleep latency > 30 minutes, poor sleep quality, and insomnia (outcomes) with the evening diet-related variables. Linear regression analyses evaluated differences in sleep duration and latency associated with the same variables. Restricted cubic splines were used to study the shape of the association of eating event clock time and TEM with sleep duration and latency.

Results Each additional hour of evening eating clock time and of the TEM, respectively increased and decreased, the odds of sleep duration < 7/h [OR(95%CI):1.30(1.20,1.40); OR(95%CI):0.51(0.47,0.56)], sleep latency > 30min [OR(95%CI):1.14(1.07,1.22); 0.88(0.83,0.94)], poor sleep quality [OR(95%CI):1.21(1.13,1.30); 0.80(0.76,0.85)] and insomnia [OR(95%CI):1.12(1.04,1.20); 0.89(0.84,0.95)]. We found a dose-response association between evening eating (clock time and TEM) and sleep duration. The shortest latency was seen when evening eating was ∼20:00 and ∼7–8 hours before the midpoint of sleep. Participants who reported dinner as the largest meal and consumed caffeine and sugary foods/beverages after 18:00 presented higher odds of sleep duration < 7 hours, poor quality, and insomnia.

Conclusions Our findings indicate that an early-eating schedule has beneficial sleep effects and that it will be necessary to consider evening eating patterns and timing, along with the existing sleep and circadian hygiene, to improve sleep quality and circadian health.
Safety and Efficacy of Novel Cost-Effective EUS Coiling and Glue Technique for the Management of Large Gastric Varices: A Long-Term Follow-up Study
Authors: Khare Shivam , Arora Anil , Varghese Jijo , Singla Vikas , Rahman Asif , Kumar Ashish , Ranjan Piyush , Kumar Mandhir , Sharma Praveen , Bansal Naresh , Anikhindi Shrihari , Sachdeva Munish , Khandelwal Asheish , Gupta Mayank , Giri Suprabhat
Published: December 2024

Aims and Objective Mortality by gastric variceal bleeding can reach up to 30%. Gastric varices can be treated by either direct endoscopic glue or endoscopic ultrasound (EUS) coiling + glue injection. Now, enough data show that EUS coil + glue is an effective option for large varices. However, it is a costlier option than direct endoscopic glue injection. In our study, after putting the coil under EUS guidance, direct endoscopic glue injection is done with a 21G sclerotherapy needle. Since the EUS needle was not used for the glue injection, it can be reused for up to three cases for deployment of the EUS coil, hence reducing the cost of the whole procedure. In short, our study aims to find the safety and efficacy of a cost-effective method of EUS coiling + glue injection in a cohort of the Indian population.

Material and Methods Retrospective review of prospectively collected data on EUS coiling + direct endoscopic glue injection over a period spanning from July 2017 to December 2023 from a tertiary care center in North India.

Results A total of 103 patients (gastroesophageal varices type 2, GOV2 [n = 82] and isolated gastric varices type 1, IGV1 [n = 21]) were taken up for the study. Among the 103 patients, 74 patients were males and 29 were females. The mean follow-up duration of the study population was 34.2 ± 21 months. The average size of the varix was 2.3 cm. The average number of coils was 3.3 and the volume of injected glue was 3.1 mL. In our study, 4 out of 103 patients had rebleeding, but the cause of rebleeding turned out to be nonvariceal. Regarding the intraprocedural and postprocedural adverse events, 1 out of 103 patients in our study experienced abdominal pain and fever, which responded to oral analgesics and antipyretics. There was no active bleeding from the puncture site or evidence of systemic embolization. Technical success was 100% in our study. Reuse of needles was not associated with any increment in risk of infection.

Conclusion EUS coiling + direct endoscopic glue injection is a safe and effective endoscopic therapy for large gastric varices with sustainable long-term beneficial effects with a negligible amount of rebleeding. Direct endoscopic injection of glue following EUS coiling with a 21G sclerotherapy needle can significantly reduce the cost of the procedure without any risk of infection.
Isolated Right Atrial Enhancement with Atrial Standstill: An Uncommon Presentation of Emery–Dreifuss Muscular Dystrophy
Authors: Biradar Basavaraj , Valakkada Jineesh , Ayyappan Anoop , Alex Ajay
Published: December 2024

Emery–Dreifuss muscular dystrophy (EDMD) is a rare inherited syndrome that affects muscles, joints, and the heart. The classic clinical triad includes early joint contractures, slowly progressive muscle weakness, and cardiac abnormalities. The common cardiac manifestations include conduction disturbances, systolic dysfunction, and dilated cardiomyopathy and may be associated with left ventricular noncompaction with an increased risk of thromboembolic events. Conduction disturbances include atrial arrhythmias, atrial standstill, complete heart block, or ventricular tachyarrhythmia. Cardiac magnetic resonance imaging (CMR) can help in the diagnosis of this condition by identifying chamber dilatation, systolic dysfunction, and late gadolinium enhancement of the atrium. Additional MRI finding of paraspinal muscle atrophy, an important finding in this muscular dystrophy, helped in reaching a confident imaging diagnosis. Our case in this article highlights the clinical and CMR findings of this rare condition.
Stoma-Related Complications: Frequency of Postoperative Morbid Events and Factors Related to Adverse Outcomes
Authors: Zubillaga-Mares Asya , Alvarez-Bautista Francisco Emmanuel , Cárdenas-Lailson Eduardo , Nájera-Saldaña Alberto , Nuñez-Venzor Alejandra , Meza-Hernández Javier Andrés , Serrano-Sánchez Minnet , Trejo-Ávila Mario
Published: December 2024

Introduction Stoma placement is a common surgical procedure that can be performed in the context of urgent and elective surgery for benign and malignant conditions, with an estimated morbidity ranging from 21% to 70%.

Methods A retrospective cohort analysis to determine the incidence of stoma placement postoperative-related complications and potential associated factors. This study was conducted at a single tertiary care center in Mexico City including all patients who underwent a stoma construction between January 2016 and October 2023.

Results A total of 276 patients underwent stoma construction. Eighty-one (29.3%) patients presented morbidity exclusively related to the ostomy.

The multivariate analysis showed the following risk factors: advanced age for developing stoma-related complications; obesity for developing parastomal hernia; strangulated hernia and complicated diverticular disease for developing mucocutaneous dehiscence; bowel obstruction and parastomal hernia for developing stomal prolapse; anastomotic leak and preoperative corticosteroid therapy for developing parastomal abscess; and end-colostomy and advanced age for reoperation.

Discussion Ostomy creation carries a high morbidity rate. Preoperative features such as advanced age, obesity, corticosteroid therapy, the indication of the surgery, as well as the type of the stoma created must be considered as they could significantly impact the development of adverse outcomes.
Epidemiological Data from Patients Who Underwent Colonoscopy from High-Susceptibility Vacancies
Authors: Martins Ana Claudia , Miranda Vera Lúcia , Junior Milton Brandão Monteiro , Silva Mayra dos Santos
Published: December 2024

Objective The objective of this study was to analyze the epidemiological profile of patients to propose measures that facilitate regulation and access to diagnostic imaging exams.

Methods Data were collected from 157 scheduled exams for high-suspicion colonoscopy through regulation systems and electronic medical records from January to December 2023. Results: The data showed a higher rate of appointments among females, particularly in older age groups (71–80 years). There was a high rate of non-attendance on the day of the exam scheduled during the coldest months of the year. The most prevalent biopsy location was the colon region, with a predominance of low-grade adenomas and polyps.

Conclusion Facilitating access to diagnostic imaging exams includes regionalization in scheduling. Monitoring results allows for the tracking of family members, enabling preventive action and early diagnosis.
Comparisons of the Efficacy of Ligasure Hemorrhoidectomy in Grade 3 and 4 Hemorrhoid Diseases
Authors: Taşkin Ali Kemal , Karademir Enes
Published: December 2024

Objective In recent years, Ligasure hemorrhoidectomy has been preferred in the treatment of grade 3 and 4 hemorrhoids rather than traditional surgery. This study aimed to compare the efficacy of Ligasure hemorrhoidectomy in grade 3 and 4 hemorrhoid treatment.

Methods A retrospective examination was made of the files of patients who underwent Ligasure hemorrhoidectomy because of grade 3 or 4 hemorrhoids. The demographic and clinical data of the patients were recorded. To evaluate pain severity after the procedure, a Visual Analog Scale (VAS) was used, and patient satisfaction at 6 months after the procedure was evaluated with a Likert-type scale. Early and late complications were determined in these follow-up examinations.

Results The patients included in the study had a mean age of 45 ± 11 years and 82 (75.9%) were male. The mean follow-up period was 18 months (range, 6–44 months). The mean age of patients with grade 4 hemorrhoid was significantly higher than that of those with grade 3 hemorrhoid (p = 0.006). Postoperative early and late (relapse) complications were seen at a higher rate in grade 4 patients compared with grade 3, but the difference was not statistically significant. More successful treatment outcomes were observed in grade 3 patients than in those with grade 4 hemorrhoid, but not to a statistically significant level.

Conclusion Ligasure hemorrhoidectomy is safer in terms of postoperative complications and treatment success is greater in patients with grade 3 hemorrhoids compared with those with grade 4 hemorrhoids.
8 Bioorthogonal Supramolecular Assemblies in Cells
Authors: Geng J. , Sapkota N.
Published: December 2024

This review addresses the concept and mechanisms of bioorthogonal supramolecular self-assembly in living organisms. It introduces bioorthogonal chemistry, which allows chemical reactions to occur within biological systems without interfering with natural processes. Key mechanisms reviewed include intracellular polymerization, host–guest interactions involving macrocyclic molecules, enzyme-mediated assembly, and peptide self-assembly. These processes mimic the way nature constructs complex structures and are crucial for applications in drug delivery, bioimaging, and diagnostics, paving the way for advancements in personalized medicine and cancer therapy.
Bridging the critical gap between infectious disease blood donation screening and connection to healthcare services: the American Chagas disease example
Authors: Lynn M. K. , Parker Mary , Stramer Susan L. , Townsend Rebecca L. , Nolan Melissa S.
Published: December 2024

Chagas disease (Trypanosoma cruzi infection) affects ~ 290,000 USA residents and is included in routine blood donation screening panels. Donors are notified of positive T. cruzi-screening results, deferred from donation, and given limited information for next steps. Individuals living with undiagnosed, uncommon infections often face substantial barriers in accessing physicians with infectious disease competency, confirmatory testing, and continuum of care after the point of blood donor deferral. We assessed 46 T. cruzi-deferred donors’ experience following deferral, highlight donor challenges, and provide public health institution opportunities to support cases of rare transfusion-transmitted infections in the USA.
Digital replicas and democracy: issues raised by the Hollywood actors’ strike
Authors: Yamazaki Asuka
Published: December 2024

Recent years have seen artificial intelligence (AI) technologies from large companies increasingly privatize people’s data, creating asymmetrical and undemocratic economic relations. Specifically, generative AI disseminates false information, distorts perceptions, and transforms the free and critical cultural public sphere into one that is privatized and undemocratic. This study examines the major Screen Actors Guild-American Federation of Television and Radio Artists strike in Hollywood in May 2023, focusing on the issues raised against actors’ digital replicas from a democratic perspective. The introduction of this technology, aiming to enhance the audience’s immersive experience, reinforces the cultural imperialistic and neoliberal hierarchical relation between companies and actors. Moreover, this study explains how digital replicas relegate actors to a subjugated state, damage their image, and demote them to the periphery of filmmaking, thereby resulting in undemocratic problems that deprive them of their subjectivity and creativity. The main findings are as follows: (1) Actors’ data, embedded in the data capitalism structure, are used to generate their digital replicas, thus causing economic and structural inequalities. Video companies’ monopolization and unapproved use of such data lead to the loss of these actors’ freedom and humanity. (2) Unauthorized digital replicas of actors through deepfakes globally damage their public image and social authority, and such false body representation has negative cultural and ontological effects on them. (3) The use of digital replicas excludes actors from the filmmaking process, eliminating their interaction and creativity in relation to other creators and audiences and preventing their participation in the critical and cultural public sphere of cinema. As humans and generative AI continue to coexist, using digital replicas with actors’ legal consent is important as it ensures their independence and expressive potential. This will develop a democratic film industry that enhances the interactive cinema–media cultural public sphere.
ELM-free enhanced D
α
H-mode with near zero NBI torque injection in DIII-D tokamak
Authors: Macwan T. , Barada K. , Parisi J. F. , Groebner R. J. , Rhodes T. L. , Banerjee S. , Chrystal C. , Pratt Q. , Yan Z. , Wang H. , Zeng L. , Austin M. E. , Crocker N. A. , Peebles W. A.
Published: December 2024

Enhanced Dα H-mode (EDA H-mode), an ELM-free H-mode regime, and the concomitant quasi-coherent mode (QCM) are explored in neutral beam heated, lower single null plasmas with near zero external torque injection. This regime exhibits good energy confinement (H98y2 ∼ 1) with βN ∼ 2, high density, regime access at low input power, and no ELMs. New time–resolved measurements of electron and ion density, temperature, plasma rotation, and radial electric field as well as turbulence, flows, thermal and particle transport, and linear instability calculations examining the dynamics of the QCM are presented. Measurements using multiple fluctuation diagnostics reveal the QCM to be a separatrix spanning mode, peaking just inside the separatrix, existing in a wide range of k⊥ρs ∼ 0.1–1.2 with multiple harmonics, and propagating with a very small phase velocity in the plasma frame, where k⊥ is the binormal wavenumber and ρs is the ion sound radius. Linear gyrokinetic simulations of this EDA H-mode discharge with CGYRO indicate that the trapped electron mode (TEM) and electron temperature gradient mode are the dominant instabilities in the radial region where QCM is also unstable. Qualitative analysis indicates that the properties of TEM are consistent with the experimentally observed characteristics of the QCM. These similarities suggest that the QCM is consistent with a TEM instability existing in the edge region of the EDA H-mode plasmas.
Recent developments in microfluidic passive separation to enable purification of platelets for transfusion
Authors: Dinh Mai T. P. , Iqbal Mubasher , Abhishek Kumar , Lam Fong W. , Shevkoplyas Sergey S.
Published: December 2024

Platelet transfusion is a lifesaving therapy intended to prevent and treat bleeding. However, in addition to platelets, a typical unit also contains a large volume of supernatant that accumulates multiple pro-inflammatory contaminants, including residual leukocytes, microaggregates, microparticles, antibodies, and cytokines. Infusion of this supernatant is responsible for virtually all adverse reactions to platelet transfusions. Conventional methods for removing residual leukocytes (leukoreduction) and reducing the volume of transfused supernatant (volume reduction) struggle to mitigate these risks holistically. Leukoreduction filters can remove leukocytes and microaggregates but fail to reduce supernatant volume, whereas centrifugation can reduce volume, but it is ineffective against larger contaminants and damages platelets. Additionally, platelet purification based on these methods is often too logistically complex, time-consuming, and labor-intensive to implement routinely. Emerging microfluidic technologies offer promising alternatives through passive separation mechanisms that enable cell separation with minimal damage and drastically reduced instrumentation size and facility requirements. This review examines recent innovations in microfluidic cell separation that can be used for leukoreduction and volume reduction of platelets. It begins by defining the performance requirements that any separation method must meet to successfully replace conventional methods currently used to perform these tasks. Standard performance metrics are described, including leukocyte depletion efficiency, degree of volume reduction, processing throughput, and platelet recovery. Finally, the review outlines the primary challenges that must be overcome to enable simple-to-use, disposable microfluidic devices capable of both reducing the platelet unit volume and removing pro-inflammatory contaminants, while preserving most functional platelets for transfusion.
Accurate numerical simulations of open quantum systems using spectral tensor trains
Authors: Grimm Ryan T. , Eaves Joel D.
Published: December 2024

Decoherence between qubits is a major bottleneck in quantum computations. Decoherence results from intrinsic quantum and thermal fluctuations as well as noise in the external fields that perform the measurement and preparation processes. With prescribed colored noise spectra for intrinsic and extrinsic noise, we present a numerical method, Quantum Accelerated Stochastic Propagator Evaluation (Q-ASPEN), to solve the time-dependent noise-averaged reduced density matrix in the presence of intrinsic and extrinsic noise. Q-ASPEN is arbitrarily accurate and can be applied to provide estimates for the resources needed to error-correct quantum computations. We employ spectral tensor trains, which combine the advantages of tensor networks and pseudospectral methods, as a variational ansatz to the quantum relaxation problem and optimize the ansatz using methods typically used to train neural networks. The spectral tensor trains in Q-ASPEN make accurate calculations with tens of quantum levels feasible. We present benchmarks for Q-ASPEN on the spin-boson model in the presence of intrinsic noise and on a quantum chain of up to 32 sites in the presence of extrinsic noise. In our benchmark, the memory cost of Q-ASPEN scales as a low-order polynomial in the size of the system once the number of system states surpasses the number of basis functions used in the spectral expansion.
Titrating chimeric antigen receptors on CAR T cells enabled by a microfluidic-based dosage-controlled intracellular mRNA delivery platform
Authors: Chen Yu-Hsi , Mirza Mahnoor , Jiang Ruoyu , Lee Abraham P.
Published: December 2024

Chimeric antigen receptor (CAR) T-cell therapy shows unprecedented efficacy for cancer treatment, particularly in treating patients with various blood cancers, most notably B-cell acute lymphoblastic leukemia. In recent years, CAR T-cell therapies have been investigated for treating other hematologic malignancies and solid tumors. Despite the remarkable success of CAR T-cell therapy, cytokine release syndrome (CRS) is an unexpected side effect that is potentially life-threatening. Our aim is to reduce pro-inflammatory cytokine release associated with CRS by controlling CAR surface density on CAR T cells. We show that CAR expression density can be titrated on the surface of primary T cells using an acoustic-electric microfluidic platform. The platform performs dosage-controlled delivery by uniformly mixing and shearing cells, delivering approximately the same amount of CAR gene coding mRNA into each T cell.
Experimental and numerical simulation study on the CO2 pre-injection fracturing optimization parameters in continental shale oil
Authors: Li Zhongxin , Lin Chengyan , Shi Xueying , Dong Xu , Su Xianheng , Pan Zhejun , Liu Bo , Suo Yu
Published: December 2024

The CO2 pre-injection fracturing technique is widely used in the development of shale oil. To address the unclear mechanism of fracture creation in CO2 pre-injection fracturing, a study was conducted on the multi-fracture propagation model for lacustrine shale oil using CO2 pre-injection fracturing. This study revealed the changes in rock mechanical parameters during CO2 pre-injection fracturing, clarified the mechanisms of shale failure and fracture propagation, and optimized the parameters for CO2+water-based fluid fracturing to guide field operations. The research findings indicate that water-based fracturing fluid has a greater impact on the tensile strength and fracture toughness of shale samples compared to CO2+water-based fracturing fluid. CO2 can mitigate the adverse effects of water-based fracturing fluid on the rock's tensile strength and fracture toughness. Introducing CO2 before slickwater can partially restore the brittleness of shale, which is conducive to increasing the complexity of fracture networks. Reducing the viscosity of the water-based fracturing fluid and increasing the volume of CO2 injection are effective measures to enhance the modified volume. Increasing the stage spacing can improve the modified volume but may reduce fracture complexity. As the angle between natural fractures and the maximum horizontal principal stress decreases, the complexity of fractures created by CO2 pre-pad fracturing initially increases and then decreases, while the modified volume initially decreases and then increases.
Abnormal magnetic field topology in the beam-plasma instability driven by ion dynamics
Authors: Liu Yi-Nuo , Hu Zhang-Hu , Xu Wang-Wen , Lan Jie-Jie , Wang You-Nian
Published: December 2024

We report on abnormal topological structures in the particles and electromagnetic field distributions induced by current filamentation instability, with emphasis on the effects of plasma ions. In the plasma filament (PF) situation, the transverse magnetic field reaches its maximum at the edge of the plasma filaments, in contrast to the case of beam filament (BF, i.e., the magnetic field reaches the maximum at the edge of the beam filaments). An analytical model is proposed to estimate the response time of the beam electrons and plasma ions, which is essential to determine the criterion of PF occurrence. With increase in beam energy and density, and decrease in plasma ion mass, the transition from BF to PF can be observed. The results are also confirmed by detailed electromagnetic particle-in-cell simulations. Moreover, the influence of PF on the synchrotron photon emission power is also discussed.
MeV x-ray production from a petawatt laser in the regime of a relativistically transparent preplasma, with applications to radiography
Authors: Strehlow J. , Yin L. , Wong C.-S. , Luedtke S. V. , Palaniyappan S. , Stark D. J. , Huang C.-K. , Bogale A. , Cage B. , Coffman T. A. , Figueroa Bengoa A. , Fitzgarrald R. , Mix L. T. , Nedbailo R. , Rusby D. R. , Schmidt J. L. , Twardowski J. , Van Pelt A. , Day T. H. , Jones B. J. , Bruce S. A. , Helal A. , Spinks M. M. , Quevedo H. J. , Beg F. N. , Chowdhury E. A. , Ditmire T. , Liang E. , Thomas A. G. R. , Fernández J. C. , Gautier D. C. , Hunter J. , Kim Y. , Meaney K. D. , Albright B. J.
Published: December 2024

Bright sources of mega-electron volt (MeV) x-rays have many unique applications, including nuclear physics, radiation oncology, and imaging high areal density systems. High intensity lasers (>1018 W cm−2) incident on mm-thick metal targets can deliver MeV x-rays via the bremsstrahlung process, providing sources with ultrashort duration (∼ps) and small source size (∼100 μm). Here, we report on a reproducible regime of laser-driven MeV x-ray sources, where the x-ray dose can be further increased by 60% by coating the metal target with micrometers of plastic. High fidelity numerical simulations indicate that the interaction is a result of relativistic transparency in the preplasma. Though relativistic transparency is present in both cases, the greater sound speed and smaller ion inertia of the plastic target allow the laser to more deeply penetrate and couple more efficiently to electrons. Radiography with this system demonstrates a resolving power < 300 μm, important for imaging applications.
Ratcheting fluid pumps: Using generalized polynomial chaos expansions to assess pumping performance and sensitivity
Authors: Moin Zain , Miller Laura A. , Battista Nicholas A.
Published: December 2024

A large diversity of fluid pumps is found throughout nature. The study of these pumps has provided insights into fundamental fluid dynamic processes and inspiration for the development of micro-fluid devices. Recent work by Thiria and Zhang [Appl. Phys. Lett. 106, 054106 (2015)] demonstrated how a reciprocal, valveless pump with a geometric asymmetry could drive net fluid flow due to an impedance mismatch when the fluid moves in different directions. Their pump's geometry is reminiscent of the asymmetries seen in the chains of contractile chambers that form the insect heart and mammalian lymphangions. Inspired by these similarities, we further explored the role of such geometric asymmetry in driving bulk flow in a preferred direction. We used an open-source implementation of the immersed boundary method to solve the fluid-structure interaction problem of a viscous fluid moving through a sawtooth channel whose walls move up and down with a reciprocal motion. Using a machine learning approach based on generalized polynomial chaos expansions, we fully described the model's behavior over the target 3-dimensional design space, composed of input Reynolds numbers (Rein), pumping frequencies, and duty cycles. Scaling studies showed that the pump is more effective at higher intermediate Rein. Moreover, greater volumetric flow rates were observed for near extremal duty cycles, with higher duty cycles (longer contraction and shorter expansion phases) resulting in the highest bulk flow rates.
Oscillatory and negative magnetoresistance in granular nanowires of superconducting NiBi3
Authors: Nanda Laxmipriya , Das Bidyadhar , Sahoo Subhashree , Sahoo Pratap K. , Senapati Kartik
Published: December 2024

Local fluctuations in the superconducting order parameters in granular systems show interesting magnetotransport behavior, particularly relevant to superconducting nanowires. Kivelson and Spivak [Phys. Rev. B 45, 10490 (1992)] have shown that fluctuations in density and signs of supercurrent can lead to oscillating and negative magnetoresistance (MR). Here, we present magnetoresistance measurements of 100 nm wide NiBi3 superconducting nanowires, patterned by focused ion beam lithography, from granular NiBi3 films containing different concentrations of magnetic Ni impurities. The nanowire containing a higher concentration of Ni impurity showed oscillations in MR and simultaneously exhibited negative MR in certain temperature and field ranges. None of these effects were observed in the nanowire with nearly no Ni impurities. Unlike earlier experiments, we argue that excess magnetic Ni impurities in the nanowire realize a case of simultaneous magnitude and sign fluctuations in local order parameter, leading to MR oscillations and MR sign reversal in the same system, as discussed by Kivelson and Spivak. This result is important in the context of transport in superconducting quantum circuits.
Data science shows that entropy correlates with accelerated zeolite crystallization in Monte Carlo simulations
Authors: Hong Seungbo , Pireddu Giovanni , Fan Wei , Semino Rocio , Auerbach Scott M.
Published: December 2024

We have performed a data science study of Monte Carlo (MC) simulation trajectories to understand factors that can accelerate the formation of zeolite nanoporous crystals, a process that can take days or even weeks. In previous work, MC simulations predicted and experiments confirmed that using a secondary organic structure-directing agent (OSDA) accelerates the crystallization of all-silica LTA zeolite, with experiments finding a three-fold speedup [Bores et al., Phys. Chem. Chem. Phys. 24, 142–148 (2022)]. However, it remains unclear what physical factors cause the speed-up. Here, we apply data science to analyze the simulation trajectories to discover what drives accelerated zeolite crystallization in MC simulations going from a one-OSDA synthesis (1OSDA) to a two-OSDA version (2OSDA). We encoded simulation snapshots using the smooth overlap of atomic positions approach, which represents all two- and three-body correlations within a given cutoff distance. Principal component analyses failed to discriminate datasets of structures from 1OSDA and 2OSDA simulations, while the Support Vector Machine (SVM) approach succeeded at classifying such structures with an area-under-curve (AUC) score of 0.99 (where AUC = 1 is a perfect classification) with all three-body correlations and as high as 0.94 with only two-body correlations. SVM decision functions reveal relatively broad/narrow histograms for 1OSDA/2OSDA datasets, suggesting that the two simulations differ strongly in information heterogeneity. Informed by these results, we performed pair (2-body) entropy calculations during crystallization, resulting in entropy differences that semi-quantitatively account for the speedup observed in the previous MC simulations. We conclude that altering synthesis conditions in ways that substantially change the entropy of labile silica networks may accelerate zeolite crystallization, and we discuss possible approaches for achieving such acceleration.
The V30 benchmark set for anharmonic vibrational frequencies of molecular dimers
Authors: Hoja Johannes , Boese A. Daniel
Published: December 2024

Intermolecular vibrations are extremely challenging to describe but are the most crucial part for determining entropy and hence free energies and enable, for instance, the distinction between different crystal-packing arrangements of the same molecule via THz spectroscopy. Herein, we introduce a benchmark dataset—V30—containing 30 small molecular dimers with intermolecular interactions ranging from exclusively van der Waals dispersion to systems with hydrogen bonds. All the calculations are performed with the gold standard of quantum chemistry CCSD(T). We discuss vibrational frequencies obtained via different models starting with the harmonic approximation over independent Morse oscillators up to second-order vibrational perturbation theory (VPT2), which allows a proper anharmonic treatment including coupling of vibrational modes. However, large amplitude motions present in many low-frequency intermolecular modes are problematic for VPT2. In analogy to the often used treatment for internal rotations, we replace such problematic modes by a simple one-dimensional hindered rotor model. We compare selected dimers to the available experimental data or high-level calculations of potential energy surfaces and show that VPT2 in combination with hindered rotors can yield a very good description of fundamental frequencies for the discussed subset of dimers involving small and semi-rigid molecules.
Stability of the flow due to a heated stretching sheet
Authors: Hanevy N. , Trevelyan P. M. J. , Stephen S. O. , Griffiths P. T.
Published: December 2024

The stability of the flow induced by a linearly stretched, flat sheet with a temperature gradient between the sheet and the free stream is investigated via a complementary numerical and large Reynolds number lower-branch asymptotic analysis. This analysis involves the derivation of new basic flow solutions which extend the exact analytical solutions of Crane, by coupling the energy and momentum equations with a temperature-dependent viscosity. In the most extreme case considered, the Reynolds number at which instabilities are observed is approximately halved compared to the isothermal case, thereby justifying its consideration as a physically meaningful flow variable of interest with potential implications for industrial extrusion processes.
Piezoelectret metamaterials with a double-V structure exhibiting tunable piezoelectric effect in a broad range
Authors: Shi Zhiming , Hu Qianqian , Altmann Alexander A. , von Seggern Heinz , Sessler Gerhard M. , Kupnik Mario , Zhukov Sergey , Ma Xingchen , Zhang Xiaoqing
Published: December 2024

Piezoelectret metamaterials are a kind of piezoelectrets with distinctive properties such as negative Poisson's ratio and positive piezoelectric d31 coefficient. These materials hold significant promise for applications in sensing and mechanical energy harvesting. In this article, flexible piezoelectret metamaterials with a simple double-V cell structure are designed, and their properties are theoretically analyzed, simulated, and experimentally tested. The results indicate that the effective piezoelectric d33 and d31 coefficients can be tuned over a wide range by adjusting the geometric parameters of the cell. The experimental results are consistent with the theoretical prediction and simulation calculation. Differing from the piezoelectric d33 coefficient, which always has positive polarity, the sign of the piezoelectric d31 coefficient depends on Poisson's ratio of the material. In particular, d31 coefficients are negative for the materials with positive Poisson's ratio, while they have a positive sign when Poisson's ratio is negative. For a piezoelectret metamaterial sample prepared in this study, a large effective piezoelectric d31 coefficient up to 1200 pC/N is achieved experimentally. The significant piezoelectric effects in the piezoelectret metamaterials as well as their excellent mechanical adaptivity to irregular surface structures, such as the curved surfaces of humanoid robots and aircraft wings, introduce a novel solution for diverse applications.
Revisiting cavity-coupled 2DIR: A classical approach implicates reservoir modes
Authors: Pyles Cynthia G. , Simpkins Blake S. , Vurgaftman Igor , Owrutsky Jeffrey C. , Dunkelberger Adam D.
Published: December 2024

Significant debate surrounds the origin of nonlinear optical responses from cavity-coupled molecular vibrations. Several groups, including our own, have previously assigned portions of the nonlinear response to polariton excited-state transitions. Here, we report a new method to approximate two-dimensional infrared spectra under vibrational strong coupling, which properly accounts for inhomogeneous broadening. We find excellent agreement between this model and experimental results for prototypical systems exhibiting both homogeneous and inhomogeneous broadening. This work implies that reservoir excitation is solely responsible for all optical response measured after the polariton modes dephase and represents an important new method for predicting and interpreting the nonlinear optical response of molecular vibrational polaritons.
Mechanistic insights into waterjet-guided laser grooving of silicon: Impact of ablation dynamics, oxide formation, and thermal stress
Authors: Hu Xinlan , Shi Tielin , Long Yuhong , Huang Yuxing , Zhang Guanghui
Published: December 2024

Waterjet-guided laser machining of silicon offers precision with minimal heat-affected zones (HAZs), but understanding the mechanisms behind laser-material interactions remains essential. This study first utilizes orthogonal experiments to reveal fundamental relationships between processing parameters (scanning cycle, laser fluence, scanning velocity, and waterjet pressure) on groove depth and the depth-to-HAZ ratio. These findings guide the in-depth investigation of laser-material mechanisms. The results indicate that the ablation rate decreases with increasing scanning cycles, a phenomenon primarily attributed to the different absorption rates of 532 nm laser light between silicon and silicon dioxide. This conclusion is supported by x-ray photoelectron spectroscopy(XPS) results, which reveal that the accumulation of silicon dioxide occurs as the scanning cycles increase. Additionally, a near-linear relation between the ablation rate and laser fluence is observed, as the ablated area is continuously exposed to high laser intensity regions. However, increasing laser fluence also leads to diminished processing quality due to greater thermal deformation in non-ablating regions. Last, increased scanning velocity is found to cause rougher surfaces, as insufficient heat diffusion leads to higher thermal stress and results in micro-crack formations. The results provide a detailed understanding of the laser-induced transformations in the material and highlight optimal conditions for reducing thermal damage while maintaining machining efficiency. This study advances the field of laser processing by offering insights into the mechanisms governing oxide formation, thermal cracking, and material deformation during silicon grooving, providing the foundation for future exploration of laser-material interaction dynamics.
Instability prediction under distorted inflow based on deep learning neural networks in an axial flow compressor
Authors: Li Jichao , Deng Yuyang , Zhang Xiaoyu , Wang Wentao , Fan Boning , Peng Feng
Published: December 2024

Traditional stall prediction methods often rely on empirical formulas and models, which have certain limitations. The deep learning model was introduced to predict stall and surge under distorted inflow conditions in an axial flow compressor, and the model can learn from the dynamic pressure data containing stall processes measured on the casing wall by use of a long short-term memory neural network. In order to enhance the model's generalization capability and prediction accuracy, the model parameters are optimized through the Northern Goshawk optimization algorithm. In the experimental validation, the stall prediction model was first trained by using the collected stalling signal. Then, a step-by-step prediction method was used to verify the accuracy of the prediction model under uniform and distorted inflow conditions. Subsequently, the recursive prediction technology is used to predict the instability under different inflow conditions in both subsonic and supersonic axial flow compressors. By comparing with the measured stalling data under uniform and distorted inflow, the model accurately and timely predicts stall and surge signal through a self-learning mechanism when inputting non-stall pressure data. Regardless of whether the instability routes are spikes and modal-wave stall or surge, the model can predict the instability at least 1 s in advance, and it leaves enough time for the anti-surge actuator to operate. This study not only significantly improves the real-time and accuracy of predictions but also demonstrates the potential application value of deep learning in the field of aero engines, contributing to enhanced safety and reliability of aircraft engines.
Linear and nonlinear stability analysis of double-diffusion convection in an inclined Brinkman porous media with a concentration-based internal heat source
Authors: Singh Mritunjay Kumar , Bharti Pallawi
Published: December 2024

The onset of double-diffusion convection in an inclined porous medium with a concentration-based internal heat source is investigated by performing linear and nonlinear stability analysis. The Brinkman model is employed to model the momentum equation. Effects of different parameters, such as the thermal Rayleigh number (RaT) and solutal Rayleigh number (Ras), the angle of inclination (ϕ), the Lewis number (Le), the Darcy number (Da), and the concentration-based internal heat source (Q), are shown. A normal mode technique has been employed on the disturbance equations to get the generalized eigenvalues problem, which is solved by the Chebyshev-tau method coupled with the QZ algorithm in MATLAB. It was observed that increasing the solutal Rayleigh number stabilizes the system due to the higher concentration at the lower boundary than the upper boundary. It has also been observed that decreasing the Darcy number has a destabilizing effect, which means that decreasing permeability advances the onset of double-diffusion convection. Furthermore, it was observed that an increase in the concentration-based internal heat source destabilizes the system. Our numerical results show that for Ras>0 and ϕ>0°, for all Q values, the subcritical instability only exists for transverse rolls.