bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment Outcomes in Advanced Biliary Tract Cancers: Single Institution Retrospective Analysis
Authors: Pathi Nikhil , Rajappa Senthil J. , Ayyagari Santa , Mohan M V. T. Krishna , Kumar Pavan , Pinninti Rakesh , Ladda Pallavi , Kandem Sanath , Tewani Rohan , Shah Kinjal , Bajaj Kripa , Krishnaiah Sree Rama , Gandrala Divya
Published: June 2024

Purpose Biliary tract cancers (BTCs), particularly gallbladder cancers (GBCs), are prevalent in India. Yet there are limited data on treatment outcomes. To bridge this gap, we performed an analysis of advanced BTC treatment outcomes at our institute, seeking to offer insights into real-world scenario.

Materials and Methods This is a retrospective study comprising advanced BTC patients treated at our institute from January 2015 to March 2023. We assessed demographics, treatment approaches, progression-free survival (PFS), overall survival (OS), and associated toxicities.

Results Of the 411 patients analyzed, the majority were GBC (67.3%, n = 277), while the rest were cholangiocarcinoma (CCA) (32.6%, n = 134). The median age of study population was 56 years. Palliative chemotherapy was administered in 85% (n = 349) of all patients. Gemcitabine–cisplatin doublet was the most commonly used chemotherapy regimen (80.2%, n = 280). Platinum doublets yielded higher response rates compared with single-agent/nonplatinum chemotherapy (60 vs. 30%, n = 133). The median PFS was 4 months. The median OS was 8 months with platinum doublets and 5 months with single-agent/nonplatinum chemotherapy (hazard ratio [HR]: 0.60, 95% confidence interval: [CI] 0.43–0.84, p = 0.0001). OS was no different based on the type of platinum agent used. Patients receiving multiple lines of treatment lived longer compared with those who received single line only (14 vs. 6 months, respectively, HR: 0.36, 95% CI: 0.28–0.45, p < 0.0001). Significant prognostic factors for OS were treatment with chemotherapy, platinum doublets, platinum exposure in first line, and treatment beyond first line. Grade 3 or 4 adverse effects seen were anemia (13.9%, n = 36), vomiting (4.2%, n = 11), diarrhea (3.4%, n = 9), thrombocytopenia (3.4%, n = 9), and febrile neutropenia (3.1%, n = 8).

Conclusion This analysis confirms that chemotherapy is beneficial for advanced BTC. Platinum-based doublets are more effective than single agents. There is no significant difference between cisplatin and oxaliplatin. Patients who received multiple lines of treatment had better OS.
Communication in Neuropalliative Care
Authors: Besbris Jessica , Baker Jessica , Kramer Neha M.
Published: June 2024

Serious illness communication needs are high among patients with neurological conditions, from the time of diagnosis to the end of life. This article will highlight unique needs among these patients, strategies for optimizing communication, and techniques to learn and teach these skills along the continuum of a career in neurology.
End-of-Life and Hospice Care in Neurologic Diseases
Authors: Chou Claudia Z. , Everett Elyse A. , McFarlin Jessica , Ramanathan Usha
Published: June 2024

The care of a patient with neurologic disease at end-of-life requires expertise in addressing advance care planning, hospice, symptom management, and caregiver support. Neurologists caring for patients with advanced neurologic disease often identify changes in disease trajectory, functional status, or goals of care that prompt discussions of advance care planning and hospice. Patients nearing end-of-life may develop symptoms such as dyspnea, secretions, delirium, pain, and seizures. Neurologists may be the primary clinicians managing these symptoms, particularly in the hospitalized patient, though they may also lend their expertise to non-neurologists about expected disease trajectories and symptoms in advanced neurologic disease. This article aims to help neurologists guide patients and caregivers through the end-of-life process by focusing on general knowledge that can be applied across diseases as well as specific considerations in severe stroke and traumatic brain injury, amyotrophic lateral sclerosis, Parkinson's disease, and dementia.
Update on Rehabilitation Strategies for Swimmers' Shoulder: A Narrative Review
Authors: Dcosta Selena , Nair Aishwarya
Published: June 2024

Swimmers' shoulder is one of the common overuse injuries having multifactorial causes with a gradual onset. Swimmers' experience pain in the pull-through phase, during the mid-stroke wherein the arm is maximally internally rotated and adducted. This occurs due to a significant amount of force generated by the pectorals, latissimus dorsi, subscapularis, serratus anterior, rhomboids, and supraspinatus for this movement. The repetitive use of shoulder muscles during the swim strokes predisposes it to overuse injuries among which shoulder impingement is common. It hinders participation of athletes in competitive events and reduces the efficiency of the swim performance. This review aims to provide a consolidated overview and identify various rehabilitation strategies and exercise programs for swimmers' shoulder. A thorough search was done on PubMed, ScienceDirect, Web of Science, Cochrane, CINAHL, and Clinical Key to find relevant articles in relation to the rehabilitation strategies available for swimmers' shoulder. Overall, this review suggests that aquatic concentric-eccentric exercise, Kinesio taping, land-based strengthening exercises, and rhythmic stabilization exercises significantly improve pain and functional activity in individuals with swimmers' shoulder.
Utility of F18-FDG PET/CT in the Evaluation of Pituitary Uptake
Authors: Stanly Adersh , Sunny Saumya Sara , Benjamin Justin , Asha Hesarghatta Shyamasunde , Mathew David , John Junita Rachel , Hephzibah Julie
Published: June 2024

Introduction Pituitary adenoma is the most common disease that affects the gland and may be classified as functional/nonsecretory tumors. Inflammatory/infective causes may also affect the pituitary gland. The 18F-fluorodeoxyglucose positron emission tomography/computed tomography (F18-FDG PET/CT) may have an incremental value in assessing these lesions and in determining their clinical significance.

Aim This article assesses the utility of F18-FDG PET/CT in detecting and determining clinical profile of pituitary lesions with abnormal uptake.

Methodology Retrospective analysis of all patients who underwent F18-FDG PET/CT from January 2015 to January 2023 was done. Those with abnormal pituitary uptake (standardized uptake value [SUV] > 2.5) were included in the study. SUV value along with relevant anatomical details, biochemical parameters, histopathological details, and follow-up imaging were analyzed.

Results Among 15,085 studies, a total of 36 patients (21 males/15 females, average age 47.36 years, range: 17–75 years) with pituitary uptake (0.23%) were included. Out of 36 patients, causes are primary pituitary tumor (21/36, 58%), tubercular hypophysitis (3/36, 8%), lymphocytic hypophysitis (2/36, 6%), lymphomatous involvement (2/36, 6%), autoimmune hypophysitis (1/36, 3%), questionable significance/incidental (4/36, 11%), and metastasis (3/36, 8%)—one each from neuroendocrine tumor ileum, chondrosarcoma, and adenocarcinoma lung. There was no difference in the SUV range between the different etiologies.

Among 21 patients with pituitary tumor, biochemical evaluation was done in 19 patients. Two patients were lost to follow-up and did not have biochemical evaluation. Among them, 8 underwent endoscopic transsphenoidal radical excision and 1 patient had PET-CT-guided stereotactic radiosurgery alone. In another 8 patients who had prior endoscopic transsphenoidal radical excision, uptake was noted as residual lesion on PET-CT. Of them, 3 underwent subtotal excision and 5 had PET-CT-guided stereotactic radiosurgery. Biopsy was done in 14 patients, of which 11 were macroadenoma and 3 were microadenoma. Overall, magnetic resonance imaging (MRI) brain was performed in 22 of them and the findings were concordant with F18-FDG PET/CT.

Conclusion F18-FDG PET/CT is a useful modality in the evaluation of pituitary uptake. It has an incremental value along with MRI brain and biochemical parameters and is useful for follow-up. Due to its high diagnostic accuracy, it is particularly useful in those with suspected residual/recurrent adenomas.
Building sustainable slow communities: the impact of built environments on leisure-time physical activities in Shanghai
Authors: Zhong Qikang , Li Bo , Dong Tian
Published: June 2024

In today’s world, creating safe, comfortable, and beautiful slow communities has become an urgent research topic for addressing energy crises, environmental pollution, and traffic congestion. This study explored the relationship between the built environment and residents’ leisure-time physical activities in slow communities in Shanghai. This study uses the analytic hierarchy process and entropy weight method to construct a new evaluation model to explore the sustainability mechanism. The results of the study are as follows. First, women participated in walking, jogging, and bicycling activities at a higher rate than men. Second, various leisure-time physical activities have different requirements for the built environment. Third, the built environment of slow communities in Shanghai shows a “pyramid” type of spatial stratification phenomenon. This study contributes to a new evaluation system and optimization model for promoting leisure-time physical activities, providing theoretical and methodological guidance for constructing livable slow communities in developing countries and promoting slow living.
The poverty trap: a grounded theory on the price of survival for the urban poor in Mexico
Authors: Turnbull Bernardo , Gordon Sarah Frances , Ojeda-García Angélica , Fuentes-Balderrama Jaime , Cruz del Castillo Cinthia
Published: June 2024

People living in poverty inhabit the outskirts of Mexican cities. They struggle and survive but cannot overcome poverty. The present article seeks to understand how the survival tactics of the urban poor keep them in poverty and, with this understanding, inform future interventions. A study based on qualitative grounded theory was conducted in 10 impoverished neighbourhoods in three main regions and cities in Mexico. Observational accounts and in-depth individual and group interviews were conducted with diverse social actors for 115 participants (75 women and 40 men) aged between 12 and 76 years. The data were analysed using an interpretative thematic analysis. Research findings revealed that the urban poor tackle adversities, such as a lack of basic services, health, education, environment, and nutrition. The strength, patience, and hard work employed by these individuals to survive were evident, but their actions to tackle these threats were costly. Ultimately, the urban poor remain in a cycle of poverty, or poverty traps. Interventions to fight poverty, improve life conditions, and general development must include integrated and participatory plans that consider the knowledge and strengths of the urban poor.
Waveform retrieval for ultrafast applications based on convolutional neural networks
Authors: Altwaijry Najd , Coffee Ryan , Kling Matthias F.
Published: June 2024

Electric field waveforms of light carry rich information about dynamical events on a broad range of timescales. The insight that can be reached from their analysis, however, depends on the accuracy of retrieval from noisy data. In this article, we present a novel approach for waveform retrieval based on supervised deep learning. We demonstrate the performance of our model by comparison with conventional denoising approaches, including wavelet transform and Wiener filtering. The model leverages the enhanced precision obtained from the nonlinearity of deep learning. The results open a path toward an improved understanding of physical and chemical phenomena in field-resolved spectroscopy.
A physics-constrained and data-driven method for modeling supersonic flow
Authors: Zhao Tong , An Jian , Xu Yuming , He Guoqiang , Qin Fei
Published: June 2024

A fast solution of supersonic flow is one of the crucial challenges in engineering applications of supersonic flight. This article introduces a deep learning framework, the supersonic physics-constrained network (SPC), for the rapid solution of unsteady supersonic flow problems. SPC integrates deep convolutional neural networks with physics-constrained methods based on the Euler equation to derive a new loss function that can accurately calculate the flow fields by considering the spatial and temporal characteristics of the flow fields at the previous moment. Compared to purely data-driven methods, SPC significantly reduces the dependency on training data volume by incorporating physical constraints. Additionally, the training process of SPC is more stable than that of data-driven methods. Taking the classic supersonic forward step flow as an example, SPC can accurately calculate strong discontinuities in the flow fields, while reducing the data volume by approximately 60%. In the generalization test experiment for forward step flow and compression ramp flow, SPC also demonstrates good predictive accuracy and generalization capability under different geometric configurations and inflow conditions.
Ion motion above a biased wafer in a plasma etching reactor
Authors: Qian Yuchen , Gekelman Walter , Pribyl Patrick , Piskin Tugba , Paterson Alex
Published: June 2024

The behavior of ions in the plasma is an essential component in the process of industrial etching. We studied the motions and energy distribution of argon ions in a inductively coupled plasma (ICP) etching tool, by the method of laser induced fluorescence (LIF). The silicon wafer clamped to a chuck at the bottom of the chamber was biased with a 1 MHz 1–1.2 kV peak-to-peak sinusoidal voltage. The plasma is formed with a 2 MHz ICP coil pulsed at 10 Hz. Sheath thickness was measured at different phases of the bias waveform. The experiment also compared the ion motions with and without wafer bias, as well as different switch-on time of wafer bias. For all cases, ion energy distribution functions and the two-dimensional flow pattern were studied near the center and edge of the wafer. Significant vortex flows were observed near the wafer edge. Experiments in which the wafer was biased in the plasma afterglow resulted in a narrow distribution of ion energy close to the bias voltage at the vicinity of the wafer, and the ion incident angle on the wafer was the smallest. The results were compared to simulations using the Hybrid Plasma Equipment Model code.
Design and performance study of gas–liquid separation–mixing device for electric submersible pump in high-gas-content oil wells
Authors: Yang Lele , Chen Yaoyao , Xing Shubin , Huang Chengyu , Wang Xinpeng , Xu Jingyu
Published: June 2024

In the process of oil production, wells containing gas can impact the efficiency of electric submersible pump (ESP), potentially causing gas lock. This issue can lead to the loss of lifting capacity in ESP, affecting the normal production of oil wells. To address this problem, the concept of gas separation before mixing transportation has been proposed, and a gas–liquid separation–mixing device has been designed. Experimental tests on the gas–liquid two-phase flow under various working conditions were conducted. A numerical model of the physical process was developed and validated with the experimental results. The results indicate that when the inlet flow rate exceeds 8.75 m3/h, the gas phase can be effectively accumulated in the center of the main pipeline after flowing through the guide vanes, thereby achieving efficient gas–liquid separation. Centrifugal number, which is defined as the ratio of axial flux of centrifugal force to axial flux of gravity, was proposed for evaluating the flow characteristics. When the centrifugal number exceeds 6.5, a high-quality gas core is formed in the pipe. At high inlet gas content, the volume fraction of gas in the main pipe initially decreases to 2% as the flow rate increases to 15 m3/h. However, at a flow rate of 30 m3/h, the volume fraction gradually rises to 30%, which results in a significant amount of gas being forced into the main pipe. The results are beneficial for expanding the use of ESP and improving the lifting efficiency in the development of oil field with high gas content.
A neural network-based four-body potential energy surface for parahydrogen
Authors: Ibrahim Alexander , Roy Pierre-Nicholas
Published: June 2024

We present an isotropic ab initio (para−H2)4 four-body interaction potential energy surface (PES). The electronic structure calculations are performed at the correlated coupled-cluster theory level, with single, double, and perturbative triple excitations. They use an atom-centered augmented correlation-consistent double zeta basis set, supplemented by a (3s3p2d) midbond function. We use a multilayer perceptron to construct the PES. We apply a rescaling transformation to the output energies during training to improve the prediction of weaker energies in the sample data. At long distances, the interaction energies are adjusted to match the empirically derived four-body dispersion interaction. The four-body interaction energy at short intermolecular separations is net repulsive. The use of this four-body PES, in combination with a first principles pair potential for para−H2 [J. Chem. Phys. 119, 12551 (2015)] and an isotropic ab initio three-body potential for para−H2 [J. Chem. Phys. 156, 044301 (2022)], is expected to provide closer agreement with experimental results.
Dielectric resonance of composites containing randomly distributed ZrB2 particles with continuous dual-peak microwave absorption
Authors: Peng Mengyue , Qin Faxiang
Published: June 2024

Substantial efforts have been devoted to the elaborate component and microstructure design of absorbents (inclusions) in microwave absorbing (MA) composite materials. However, the mesoscopic architecture of composites also plays a significant role in prescribing their electromagnetic properties, which is rarely explored in studies of MA materials. Herein, a composite containing randomly distributed ZrB2 particles is fabricated to offer a mesoscopic cluster configuration, which produces dielectric resonance. The resonance disappears and reoccurs when ZrB2 is coated with insulating and semiconductive ZrO2 layers, respectively, suggesting that it is a plasmon resonance excited by electron transport between ZrB2 particles in clusters rather than any intrinsic resonance of the materials constituting the composite. The resonance strength can be regulated by controlling the quantity of electron transport between particles, which is accomplished by gradually increasing the insulating ZrO2-coated ZrB2 ratio, x, to disturb the electron transport in ternary disordered composites containing ZrB2 and insulating ZrO2-coated ZrB2. When x exceeds 0.7, the electron transport is cut off completely and the resonance thus disappears. The resonance induces double quarter-wavelength (1/4λ) interference cancellations or resonance absorption coupled with 1/4λ interference cancellation, giving rise to continuous dual-peak absorption. This work highlights the significance of mesoscopic architectures of composites in MA material design, which can be exploited to prescribe electromagnetic properties.
Octave spanning and flat-top supercontinuum generation in standard foundry-compatible process-made Ge–Sb–Se chalcogenide glass waveguide
Authors: Han Fengbo , Zhou Xuecheng , Huang Yali , Huang Lu , Song Luming , Dong Zhipeng , Yu Shaoliang , Du Qingyang , Luo Zhengqian
Published: June 2024

We reported near octave-spanning supercontinuum generation in Ge28Sb12Se60 chalcogenide glass rib waveguides. The waveguides were fabricated using foundry-compatible deep ultra-violet lithography, followed by plasma etching. We demonstrated an average propagation loss of ∼1.3 dB/cm at the 1550 nm telecommunication wavelength. With dispersion engineering, optimizing waveguide geometry, and pumping by a multi-wavelength femtosecond soliton fiber laser, we achieved a flat-top supercontinuum generation spanning from 1290 to 2400 nm and beyond . It has a 3 dB bandwidth of 436 nm and a 20 dB bandwidth of more than 900 nm. The implementation of such waveguides provides a practical broadband light source solution for on-chip spectroscopy and sensing systems.
Ethical assessment of virtual consultation services: application of a practical ethical checklist to direct-to-consumer services in Aotearoa New Zealand
Authors: Reid Madeleine , Moerenhout Tania
Published: June 2024

Introduction Evaluating digital health services from an ethical perspective remains one of the more difficult challenges in telemedicine and health technology assessment. We have previously developed a practical ethical checklist comprising 25 questions covering six ethical themes: privacy, security, and confidentiality; equity; autonomy and informed consent; quality and standards of care; patient empowerment; and continuity of care. The checklist makes ethical analysis more easily accessible to a broader audience, including health care providers, technology developers, and patients. Aim This project applies the previously developed practical ethical checklist to direct-to-consumer virtual primary care consultation services in Aotearoa New Zealand to conduct an ethical assessment. Method We first mapped the available services. The ethical framework was then applied to assess these services based on publicly available information. Results Our findings show that the examined virtual consultation services adequately address ethical considerations, particularly regarding patient data privacy and informed consent. We identified areas for improvement in equity, patient empowerment, and continuity of care. Discussion The application of this framework raises fundamental questions on how continuity of care, equity, and comprehensive care can be protected when virtual care becomes more ubiquitous. The checklist can help virtual consultation services identify areas of improvement and ensure they meet ethical criteria, thus contributing to quality of care. The framework may be adapted to other digital health services and tools, providing ethical guidance to technology developers, clinicians, and patients and their whānau (family).
Implementing translanguaging strategies in the English writing classroom in higher education
Authors: Tang Xin , Rousse-Malpat Audrey , Duarte Joana
Published: June 2024

Over the past two decades, translanguaging has become a powerful concept in applied linguistics, enabling teachers
and students to respond to linguistic and cultural diversity in the classroom. However, how teachers and students prepare for
translanguaging pedagogy and practice in writing has so far received less attention (Huang
& Chalmers, 2023). Therefore, this systematic review focuses on the application of translanguaging strategies in
the English as a Foreign/Second Language (EFL/ESL) writing classroom. Following the PRISMA guidelines for systematic reviews, this
study searched five databases to obtain articles spanning from 2013 to 2023. We reviewed 23 articles focusing on translanguaging,
writing and higher education. Our results show that (1) most studies were conducted in North America and Northern Asia, with
qualitative studies being predominant; (2) most researchers implemented translanguaging interventions in the EFL/ESL classroom to
study the impact of translanguaging on students’ English writing skills; (3) students applied translanguaging strategies during
the writing process to communicate with others on content and vocabulary; (4) translanguaging strategies provided teachers with
diverse perspectives and enhanced students’ various skills; (5) the use of digital resources and different types of activities
contributed to the application of translanguaging in the writing classroom, but students’ limited language skills in their L2 but
also in their L1, and their uncertainty about their linguistic identity limited implementation of translanguaging in the English
writing classroom. This systematic review points towards the need for educators to consider the various factors, functions and
applications of the use of translanguaging strategies in English writing classrooms.
Dynamics of Carrollian scalar fields
Authors: Ciambelli Luca
Published: June 2024

Adopting an intrinsic Carrollian viewpoint, we show that the generic Carrollian scalar field action is a combination of electric and magnetic actions, found in the literature by taking the Carrollian limit of the relativistic scalar field. This leads to non-trivial dynamics: even a single particle with non-vanishing energy can move in Carrollian physics.
Reconstructing the metric in group field theory
Authors: Gielen Steffen , Mickel Lisa
Published: June 2024

We study a group field theory (GFT) for quantum gravity coupled to four massless scalar fields, using these matter fields to define a (relational) coordinate system. We exploit symmetries of the GFT action, in particular under shifts in the values of the scalar fields, to derive a set of classically conserved currents, and show that the same conservation laws hold exactly at the quantum level regardless of the choice of state. We propose a natural interpretation of the conserved currents which implies that the matter fields always satisfy the Klein–Gordon equation in GFT. We then observe that in our matter reference frame, the same conserved currents can be used to extract all components of an effective GFT spacetime metric. Finally, we apply this construction to the simple example of a spatially flat homogeneous and isotropic Universe, where we derive an effective Friedmann equation directly from this metric. The Friedmann equation displays a bounce and a late-time limit equivalent to general relativity with a single scalar field. Our proposal goes substantially beyond the GFT literature in which only specific geometric quantities such as the total volume or volume perturbations could be defined, opening up the possibility to study more general geometries as emerging from GFT.
TCAD simulation of germanium-based heterostructure solar cell employing molybdenum oxide as a hole-selective layer
Authors: Mehmood Haris , Nasser Hisham
Published: June 2024

Molybdenum Oxide (MoO
x
) has been used as a hole-extraction film for photovoltaic (PV) applications; however, its interaction with Germanium (Ge)-based solar cells is less understood. For the first time, this paper aims to physically model the Ge solar cell that incorporates MoO
x
for hole transportation at the front side of the PV device facing the sunlight. However, the charge transportation process within the PV device is influenced by several design parameters that need optimization. A higher work function of MoO
x
increases the barrier height against minority carriers of electrons which is beneficial for extricating holes at the front interface of MoO
x
/Ge. A progressive reduction in the recombination of charge carriers has been observed by including a passivation layer of amorphous silicon (i-a-Si:H). Similarly, inserting a passivation and back surface field (BSF) stack of i-a-Si:H strengthens the electric field and likewise reduces the recombination at the rear side of the device. An enhanced doping concentration of BSF assists in the favorable alignment of energy bands for improved charge transportation within the solar cell as the rear passivation maintains the field strength for accelerated movement of charge carriers. However, optimizing the thickness of the front-passivation film is challenging due to the parasitic absorption of light at larger thicknesses. A comparative study with the reference device revealed that the proposed device exhibited a step-increase in the conversion efficiency (η) from 4.23% to 13.10%, with a higher J
sc of 46.4 mA cm−2, V
oc of 383 mV, and FF of 74%. The proposed study is anticipated to meet the research gap in the physical device modelling of Ge-based solar cells employing high work function MoO
x
as a carrier-selective layer that could be conducive to the development of highly efficient multijunction solar cells.
Mastering the art of designing mechanical metamaterials with quasi-zero stiffness for passive vibration isolation: a review
Authors: Hamzehei Ramin , Bodaghi Mahdi , Wu Nan
Published: June 2024

This review serves as a comprehensive design strategy for designing quasi-zero stiffness (QZS) mechanical metamaterials (MMs). It discusses their underlying deformation mechanisms that enable the attainment of QZS behavior under both compressive and tensile loadings. While the QZS characteristic of metamaterials has garnered considerable attention, further research is essential to unlock their potential fully. Numerous QZS metamaterials have been meticulously reviewed. They comprise various elements and mechanisms, including positive and negative stiffness elements (PS and NS), PS elements with variable stiffness, bending mechanisms employing stiff joints/areas, buckling, buckling-rotating, and bending/buckling deformation mechanisms leading to a QZS feature. Furthermore, the capability of multi-material, adaptive, smart metamaterials, origami (bending around the hinge of the folded joints), and kirigami lattices (out-of-plane buckling via cutting patterns) are weighted. These diverse mechanisms contribute to achieving QZS behavior in metamaterials under both compression and tension loads, which is paramount for various mechanical applications such as passive vibration isolation. This review effectively categorizes QZS metamaterials based on their underlying mechanisms, providing scholars with valuable insights to identify suitable mechanisms for the desired QZS feature.
Magnetically-responsive microwall arrays with path-guide for directional transportation of droplets
Authors: Kwon Soyeon , Kim Jihun , Do Yoobin , Kwon Hyeokbae , Kwon Soungmin , Lee Hyun-Taek
Published: June 2024

This research provides a comprehensive exploration of the development and characterization of magnetically responsive microwall arrays (MRMAs), presenting a novel approach to precise droplet manipulation. The proposed fabrication process involves microscale wall arrays created using carbonyl iron particles embedded in polydimethylsiloxane through a replica molding process. The MRMAs demonstrate a unique response to magnetic fields, enabling precise control over droplet movement. Through superhydrophobic coatings and meticulously adjusted magnetic fields, the system facilitates the efficient movement of droplets along predefined routes, achieving outstanding accuracy in droplet directionality and positioning. The experiments highlight the capability of MRMAs to merge differently colored droplets, underscoring their potential in long-distance droplet transportation. The results suggest applications in microfluidic systems, lab-on-a-chip devices, and targeted drug delivery, marking a significant advancement in microfluidic research.
Analytical and numerical evaluation of the effective properties of macro fiber composite (MFC)
Authors: Fu Zhiqiang , Shen Yiping , Wang Songlai , Li Jian
Published: June 2024

The piezoelectric fibers of Macro Fiber Composite (MFC) have a rectangular cross-section with an aspect ratio of 2. This heterogeneity poses challenges for micromechanical modeling to predict the effective mechanical properties. The High-Fidelity Generalized Method of Cells (HFGMCs) is commonly used to calculate the properties of composite materials. In this paper, a Modified High-Fidelity Generalized Method of Cells (MHFGMC) is proposed to analyze MFC properties, in which the interaction between subcells is considered by defining the quadratic directional coupling term and the shear connection matrix. The accuracy of the proposed MHFGMC model is verified by using the finite element method and experimental tests. The results show that the MHFGMC can accurately predict the effective mechanical properties of MFC, and the relative error of tensile properties compared to experimental results is within 2.29%. The MHFGMC significantly improve the accuracy of the HFGMC, the relative error of its shear modulus is decreased from 105.13% to 0.71%.
Multimode interference coupler based on general interference for integrated optical and quantum optic devices: a review
Authors: Sahu Partha Pratim
Published: June 2024

Integrated optics play important role in the development for optical network devices, optical processing, instrumentation and quantum information device. Here, multimode interference (MMI) coupler is one of basic component preferred for these integrated optic devices in which MMI coupler based on general interference (GIMMI) has been focused for large scale integrated optic devices because of compact size in comparison to MMI coupler based restricted interference (RIMMI). In this paper, we have reviewed different GIMMI structures reported previously. Different waveguide materials are mentioned and compared for fabrication of GIMMI device. The coupling behaviors and modal analysis of GIMMI couplers and their different tapered structures are estimated by using simple model based on sinusoidal modes showing reduced coupling lengths in down tapered structures in comparison to other structures. The excess loss, polarization dependence loss and crosstalk versus fabrication tolerances are obtained to compare their performances revealing almost same losses and fabrication tolerance. The paper reports the use of the GIMMI coupler in wavelength multiplexing, power splitting, switching, optical processing. Finally, Quantum optic application of GIMMI coupler is shown indicating high quantum fidelity of 50:50 coupling ratio.
The collisional study of EIC waves in a magnetized dusty plasma with the inclusion of a DC electric field
Authors: Sharma Jyotsna , Sharma Suresh C
Published: June 2024

This study investigates Electrostatic Ion Cyclotron (EIC) waves and their behaviour in weakly collisional plasmas, utilizing a proposed kinetic analytical model. The findings include alterations in EIC wave dispersion characteristics due to collisions, with parameters such as dust density, collision frequency, gyro-radius, magnetic field, density ratio, and electric field influencing wave growth rate and frequency. Temperature analysis reveals that higher electron-to-ion temperature ratios lead to increased frequency and critical drift velocity, while decreasing the growth rate. In addition, the critical drift velocity is studied for the unstable mode and it is observed that the relative density ratio increases with a reduction in critical drift velocity. Electron collisions destabilize EIC waves, while ion collisions stabilize them. Furthermore, the presence of dust particles decreases the growth rate of EIC waves as dust grain density increases. These results align with observations reported in previous literature.
Rapid graphene oxide assisted chemical etching of silicon in HF/H2O2 solution
Authors: Xu Yajun , Zhao Qichen , Chen Jianian , Zhang Jingzhe , Xu Binbin
Published: June 2024

In recent years, graphene oxide assisted etching silicon has been considered a potential method to replace metal-assisted chemical etching. This work demonstrated the catalytic ability of graphene oxide synthesized by the Hummers method to promote chemical etching of silicon. By adjusting HF/H2O2 ratio of the solution and reaction temperature, a minimum weighted average reflectance of 9.9% in the wavelength range of 300–1100 nm was obtained. An etching rate of 10 μm h−1, faster than those in others’ reports, was obtained in an optimized acidic solution at 80 °C. Finally, a four-electron model for graphene oxide assisted etching mechanism was proposed to explain our research results.
Evaluation of rapid gas decompression (RGD) resistance of sealing materials for hydrogen-doped pipeline valves
Authors: Ouyang Xin , Peng Daigang , Peng Shiyao , Cong Chuanbo , Man Jianfeng , Wu Xuejian , Liu Xiaoben
Published: June 2024

With the rapid development of hydrogen-doped natural gas pipelines, the evaluation of the applicability of hydrogen to natural gas pipeline systems is bound to gradually involve all aspects of natural gas pipelines. Targeted at the non-metallic sealing materials for valves of hydrogen-doped natural gas pipelines, this paper, according to the ISO 23936-2 standard, carried out the rapid gas decompression (RGD) tests of hydrogenated nitrile butadiene rubber (HNBR), fluorine rubber 246 (FKM246) and fluorine rubber 26 (FKM26), and the damage level of cracking failure for the rubber materials in the course of rapid release of gaseous medium was obtained (DL). The mechanical properties and volumetric dissolution rate of the three rubber materials were tested before and after the high-pressure gas mixture treatment, which explains the reason for the cracking failure of the rubber materials during the RGD test. The study obtained the influence law of high-pressure gas mixture with different hydrogen volume fractions on the RGD resistance of HNBR, FKM246, and FKM26, and selected the material with the optimal RGD resistance as FKM26, which can be used as a reference for the selection of sealing materials for the valves of hydrogen-doped natural gas pipelines in engineering.
Comparison of composite cylinder damage under different working conditions
Authors: Yang Bo
Published: June 2024

The finite element model of the carbon fiber all-wound aluminum cylinder was created to analyze the damage caused by high pressure, and the progression of damage as pressure increased was examined. The damage initially occurs in the transitional area between the cylinder end and cylinder body before progressing to the winding layer of the cylinder. The failure characteristics of the circumferential wound layer contrast with those of the spiral wound layer.
Sensitivities of critical operating conditions on proton exchange membrane fuel cell performance: an experimental study
Authors: Li Xiaolong , Wang Xuanyu , Yang Ziqian , Liu Yupeng , Ni Zhaojing , Han Kai
Published: June 2024

The performance of the Proton Exchange Membrane Fuel Cell (PEMFC) is subject to substantial influence from operating conditions. In this paper, the impact of various operating conditions on the polarization curves is examined through single-variable polarization curve tests. Notably, it is observed that the polarization curves intersected within the range of 1.0 A/cm2 to 1.5 A/cm2 under varying cathode inlet humidity and working pressure conditions. Expanding upon this observation, an orthogonal experiment is designed and executed to evaluate the sensitivity of PEMFC performance to diverse operating conditions under two distinct current densities of 1.0 A/cm2 and 2.0 A/cm2. Consequently, it is revealed that the output voltage, charge transfer impedance, and mass transfer impedance are most significantly influenced by three specific operating conditions: temperature, cathode inlet humidity, and stoichiometric ratio. Furthermore, as the current density increases, the dominant factors governing PEMFC performance have evolved from temperature-dominated charge transfer impedance to cathode stoichiometric ratio-dominated mass transfer impedance.
Research on the underground ignition mechanism of ignition fuel and ground simulation experiments
Authors: Li Shuai , Hao Jun , Yang Gao , Zhang Youjun
Published: June 2024

In the increasingly severe environment of the “dual carbon” situation and the urgent objective demand for national energy transformation and upgrading, the development and use of clean energy have become a new research field and direction. Underground coal gasification technology (UCG) is a clean coal technology that completely bypasses the traditional coal combustion process by converting coal underground into gas and then classifying and recycling it. This method removes sulfur before fuel combustion Nitrogen compounds and particles make it clean like natural gas. The most commonly used ignition method in this technology is chemical ignition. A certain proportion of ignition fuel and main fuel is injected into the underground through pipelines, and then combustion supporting gas is introduced to cause a chemical reaction and generate an open flame to ignite the coal. However, due to the complex internal environment of the pipeline, uneven bending of the pipeline column, and the length of the pipeline exceeding one kilometer, the concentration threshold of the ignition fuel when it reaches the underground igniter cannot be accurately controlled, resulting in ignition failure. In response to the above difficulties, this article has conducted research on the ignition mechanism of ignition fuel, and developed a dedicated ground simulation test bench to conduct ground simulation experiments. The research has strong support for the on-site pilot testing and engineering services of underground coal gasification technology.
CuSO4/H2O2 induced polydopamine/polysulfobetaine methacrylate co-deposition on poly(amino acid) membranes for improved anti-protein adsorption and antibacterial activity
Authors: Chen Xiaolu , Yan Dawei , Deng Hao , Yang Hulin , Peng Suping , Zhang Wei , Cai Shijie , Zhang Qiyi , Ren Haohao , Yan Yonggang
Published: June 2024

Stopping postoperative soft tissue adhesions is one of the most challenging clinical problems that needs to be addressed urgently to avoid secondary injury and pain to patients. Currently, membrane materials with anti-protein adsorption and antibacterial activity are recognized as an effective and promising anti-adhesion barrier to prevent postoperative adhesion and the recurrent adhesion after adhesiolysis. Herein, poly(amino acid) (PAA), which is structurally similar to collagen, is selected as the membrane base material to successfully synthesize PAA-5 membranes with excellent mechanical and degradation properties by in-situ melt polymerization and hot-melt film-forming technology. Subsequently, the co-deposition of polydopamine/polysulfobetaine methacrylate (PDA/PSBMA) coatings induced by CuSO4/H2O2 on PAA-5 membranes results in the formation of PDC-5S and PDC-10S, which exhibit excellent hemocompatibility, protein antifouling properties, and cytocompatibility. Additionally, PDC-5S and PDC-10S demonstrated significant antibacterial activity against Escherichia coli and Staphylococcus aureus, with an inhibition rate of more than 90%. As a result, this study sheds light on newly discovered PAA membranes with anti-protein adsorption and antibacterial activity can sever as one of the promising candidates for the prevention of postoperative peritoneum adhesions.
Multi-parameter design of triply periodic minimal surface scaffolds: from geometry optimization to biomechanical simulation
Authors: Yang Xiaoshuai , Sun Zhongwei , Hu Yuanbin , Mi Changwen
Published: June 2024

This study introduces a multi-parameter design methodology to create triply periodic minimal surface (TPMS) scaffolds with predefined geometric characteristics. The level-set constant and unit cell lengths are systematically correlated with targeted porosity and minimum pore sizes. Network and sheet scaffolds featuring diamond, gyroid, and primitive level-set structures are generated. Three radially graded schemes are applied to each of the six scaffold type, accommodating radial variations in porosity and pore sizes. Computer simulations are conducted to assess the biomechanical performance of 18 scaffold models. Results disclose that diamond and gyroid scaffolds exhibit more expansive design ranges than primitive counterparts. While primitive scaffolds display the highest Young’s modulus and permeability, their lower yield strength and mesenchymal stem cell (MSC) adhesion render them unsuitable for bone scaffolds. Gyroid scaffolds demonstrate superior mechanical and permeability performances, albeit with slightly lower MSC adhesion than diamond scaffolds. Sheet scaffolds, characterized by more uniform material distribution, exhibit superior mechanical performance in various directions, despite slightly lower permeability. The higher specific surface area of sheet scaffolds contributes to elevated MSC adhesion. The stimulus factor analysis also revealed the superior differentiation potential of sheet scaffolds over network ones. The diamond sheet type demonstrated the optimal differentiation. Introducing radial gradations enhances axial mechanical performance at the expense of radial mechanical performance. Radially decreasing porosity displays the highest permeability, MSC adhesion, and differentiation capability, aligning with the structural characteristics of human bones. This study underscores the crucial need to balance diverse biomechanical properties of TPMS scaffolds for bone tissue engineering.
Potential use of extracted flax seed mucilage in the construction of macroporous cryo-scaffolds
Authors: Demir Didem
Published: June 2024

Mucilage is a natural source of polysaccharides that has recently attracted attention for use in biomaterial production. It attracts attention with its easy and fast extraction, biocompatibility, high water retention capacity, and biodegradability. Although there are studies on the characterization of mucilage obtained from different plant sources, the interaction of this polymer with other polymers and its potential to form new biomaterials have not yet been sufficiently investigated. Based on this, in this study, the potential of mucilage extracted from flaxseed for the production of cryogels for tissue engineering applications was demonstrated. Firstly, yield, basic physicochemical properties, morphology, and surface charge-dependent isoelectric point determination studies were carried out for the characterization of the extracted mucilage. The successful preparation of mucilage was evaluated for the construction of cryo-scaffolds and 3D, spongy, and porous structures were obtained in the presence of chitosan and polyvinyl alcohol polymers. A heterogeneous morphology with interconnected macro and micro porosity in the range of approximately 85–115 m pore diameter was exhibited. Due to the high hydrophilic structure of the mucilage, which is attached to the structure with weak hydrogen bonds, the contact angle values of the scaffolds were obtained below 80° and they showed the ability to absorb 1000 times their dry weight in approximately 30 min. As a preliminary optimization study for the evaluation of mucilage in cryogel formation, this work introduced a new construct to be developed as wound dressing scaffold for deep and chronic wounds.
Portable fiber-based double nanohole optical tweezer for trapping small proteins
Authors: Kaur Veerpal , Wright Demelza , Mathew Samuel , Peters Matthew , Zacharopoulou Maria , Hua Yang Shang , Itzhaki Laura S , Bahar Ivet , Gordon Reuven
Published: June 2024

We demonstrate the trapping and analysis of individual proteins using a portable optical fiber tweezer setup with a double-nanohole in a gold film coating the fiber’s end and aligned with the fiber core. The instrument was used to trap and analyze cytochrome c, carbonic anhydrase, bovine serum albumin, and PR65 (wild-type and various point mutants). This approach was compared with a free-space optical tweezer setup that requires alignment of the laser focus to the aperture, whereas the fiber-based approach is both portable and alignment-free, which holds promise for applications in antibody discovery, small molecule drug discovery, protein interaction analysis and other applications using the standard well-plate format.