bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimized synthesis and characterization of La(OH)3 and LaB6 nanostructures for enhanced NIR optical filters
Authors: Bulbul B G , Toprak B C , Sayrac M , Ozen Y , Ozcelik S
Published: October 2024

The present study describes a method for synthesizing nanostructured La(OH)3 and LaB6 materials with efficient field emission properties using the spin coating technique. The study was motivated by the significant demand for the optical properties of LaB6 with efficient field emission properties using the spin coating technique in the near-infrared (NIR) region. The optimization of the LaB6 synthesis process for economic and reproducible results is highlighted, showcasing a systematic approach starting from La(OH)3 formation through chemical mixing and high-temperature heating, followed by boron incorporation. The systematic methodology includes forming La(OH)3 through chemical mixing and high-temperature heating, followed by combining it with boron to achieve the LaB6 structure. Characterization methods such as XRD, FTIR, SEM, AFM, and SIMS validated the successful synthesis and uniformity of the materials. Optical analyses showed increased visible transmittance and reduced infrared transmittance for the LaB6 thin film. Optical analyses showed increased visible transmittance and decreased infrared transmittance in the 110 nm thick LaB6 film, with an absorption valley at 1000 nm. SEM images revealed microstructural features and AFM analysis indicated a homogeneous distribution of La and B atoms with an RMS value of 0.87 nm. SIMS analysis confirmed uniform atomic distribution throughout the film thickness. The optimized recipes contribute to the efficiency and controllability of the synthesis process. The presented results provide valuable insights into material synthesis methodologies and serve as a crucial reference for utilizing LaB6 materials in infrared devices.
Multi-image encryption scheme using cross-plane coupling permutation and plain-by-plain wave diffusion
Authors: Lai Qiang , Wang Huangtao , Erkan Uǧur , Toktas Abdurrahim
Published: October 2024

Images contain a wealth of visual information, are susceptible to unauthorized access due to their vulnerability and sensitivity. This paper designs a novel multi-image encryption scheme for protecting the privacy of images of different sizes and types. Initially, a 2D memristive hyperchaotic map (2D-MHM) is designed and subjected to various dynamic analyses and randomness evaluations. The results demonstrate that the proposed map possesses an exceptionally large parameter space, high Lyapunov exponent and sample entropy, and has successfully passed the entire suite of NIST test, verifying its feasibility for confidential communication. Then we present a multi-image encryption scheme combining cross-plane coupling permutation and plain-by-plain wave diffusion to realize random exchange and global variation of pixels in different planes. The performance evaluation and numerical analysis demonstrate that the scheme is resilient against multifarious types of attacks, possesses great security while effectively enhancing encryption efficiency. Finally, the proposed scheme is compared with advanced algorithms and its application in healthcare is discussed, exhibiting its superiority in multiple aspects.
Doubly warped product manifolds with the structure of hyperbolic Ricci solitons
Authors: Açıkgöz Kaya Dilek
Published: October 2024

In this paper we study hyperbolic Ricci solitons on doubly warped product manifolds. The necessary conditions are obtained for a hyperbolic Ricci soliton with the structure of a doubly warped product to be an Einstein manifold when we consider the potential field as a Killing or a conformal vector field. Also, we examined the behavior of hyperbolic Ricci solitons on doubly warped product space-times.
Tunable and strong circular dichroism metamaterial absorber based on gold-VO2 hybrid structure
Authors: Yi Qianyi , Li Jiaying , Xu Jian , Li Wei , Peng Yuxiang , Liu Yuanyuan , He Mengdong
Published: October 2024

The existing terahertz chiral absorber faces a series of issues, including low efficiency, un-tunable absorption, and complex structure. We present a chiral metamaterial absorber integrated with gold and phase-change material vanadium dioxide (VO2) to address the issues above. Our designed metamaterial absorber’s maximum circular dichroism (CD) value, as an ideal chirality-selective meta-absorber, reaches 0.95 when VO2 behaves as a metallic state. However, when VO2 is in the insulator state, the CD value is merely 0.003. Notably, the intrinsic mechanisms of the CD effect are revealed by analyzing the difference in electromagnetic response under left-handed circularly polarized (LCP) and right-handed circularly polarized (RCP) illumination. The designed chiral metamaterial absorber supports the free switching of the CD signal between ‘on’ and ‘off’ states by continuously adjusting the conductivity of VO2 with a CD value ranging from 0 to 0.95. Moreover, the absorption performance of chiral metamaterials is affected by geometric parameters and the angle of incidence. To evaluate the capability of chiral structure in biosensing, three typical avian influenza viruses are sensed by detecting changes in their resonant frequencies and CD values. Finally, the presented chiral-selective absorber with phase-change materials has an important reference value in the terahertz range for constructing chiral light detectors, chiral thermal switching, biosensors, and tunable chiral photonics.
Enchanting optical, electronic, and mechanical properties of the sodium based Na2MgSiZ6 (Z = I, Br, Cl) halides have been explored through DFT
Authors: Iqbal Javed , Ullah Habib , Archi Marouane , Ullah Naimat , Ullah Saeed , Ullah Riaz , Iqbal Zafar
Published: October 2024

Materials. with perovskite structures have been extensively studied due to their remarkable properties, which are important in various aspects of daily life. In the present approach, Na2MgSiZ6 (Z = I, Br, Cl) halides were extensively studied, and it was realized from the band structure results that all these halides display semiconducting natures with indirect band gaps. The semiconducting natures of Na2MgSiZ6 (Z = I, Br, Cl) halides were further confirmed by their TDOS results. The optimized values of the lattice constants were found to be 11.70 Å, 10.4 Å, and 10.22 Å for Na2MgSiI6, Na2MgSiBr6, and Na2MgSiCl6, respectively. Moreover, the largest volume was observed for the Na2MgSiI6 compound, while the smallest volume was recorded for the Na2MgSiCl6 compound. Na2MgSiCl6 compound exhibited brittle nature, whereas Na2MgSiBr6 and Na2MgSiI6 were found to be ductile. All three materials demonstrated attractive values of optical conductivities, making them befitting candidates for solar cells, LEDs, detectors, and various other optoelectronic devices. From the achieved negative values of formation energy for all the Na2MgSiZ6 (Z = I, Br, Cl) halides, it was comprehended that these compounds could be synthesized practically.
Coscattering in the extended singlet-scalar Higgs portal
Authors: Sáez Bastián Díaz , Lahiri Jayita , Möhling Kilian
Published: October 2024

We study the coscattering mechanism in a simple Higgs portal which add two real singlet scalars to the Standard Model. In this scenario, the lighter scalar is stabilized by a single 𝒵2symmetry and acts as the dark matter relic, whose freeze-out is driven by conversion processes. The heavier scalar becomes an unstable state which participate actively in the coscattering. We find viable parameter regions fulfilling the measured relic abundance, while evading direct detection and big-bang nucleosynthesis bounds. In addition, we discuss collider prospects for the heavier scalar as a long-lived particle at present and future detectors.
Excess cataloged X-ray and radio sources at galaxy-cluster virial shocks
Authors: Ilani Gideon , Hou Kuan-Chou , Keshet Uri
Published: October 2024

We detect a highly significant excess of X-ray (2RXS) and radio (NVSS, GMRT, VLSSr) catalog sources when stacked around MCXC galaxy clusters and groups, narrowly confined within ≲ 100 kpc of the ∼ 2.4 R
500 virial shock radius (inferred from previous continuum stacking), with similar X-ray (∼ 4σ for 443 clusters) and radio (∼ 4σ for 485 clusters) characteristics (> 5σ joint).
The excess sources show 10–100 kpc scales, LX
(0.1 – 2.4 keV)≃ 1042-43 erg s-1 or νLν
(ν = 1.4 GHz) ≃ 1040-41 erg s-1 luminosities, and a preferentially radial radio-polarization.
The narrow localization and properties of the excess identify these sources not as AGN, often invoked speculatively for excess X-ray sources at cluster outskirts, but rather as infalling gaseous clumps interacting with the virial shock, probably galactic halos and possibly outflow remnants.
The local excess of such discrete, radio-to-γ-ray sources around an object can probe its virial shock also at high redshifts and sub-cluster scales.
Sound horizon independent constraints on early dark energy: the role of supernova data
Authors: Kable Joshua A. , Miranda Vivian
Published: October 2024

We assess the consistency of cosmological models that alter the size of the sound horizon at last scattering to resolve the Hubble tension with data from ACT + Planck CMB lensing, Big Bang Nucleosynthesis, and supernova data from Pantheon or Pantheon+. We use early dark energy (EDE) as an example model but conclude that the results could apply to other similar models. We constrain ΛCDM and EDE with these data finding that while they can constrain ΛCDM very tightly, EDE opens up the parameter space significantly and allows H
0 > 72 km s-1Mpc-1. We combine these data with measurements from ACT + Planck TT650TEEE CMB primary anisotropy and galaxy baryon acoustic oscillations, and find that overall, EDE fits these data better than ΛCDM at ≈ 2σ. However, the fit to specifically the sound-horizon-independent measurements is worse for EDE than ΛCDM. We assess this increase in χ
2 coming from the sound-horizon-independent measurements and find that the best-fit model is still consistent with a random statistical fluctuation even with H
0 values around 72 km s-1Mpc-1. Finally, we find that supernova data play an important role in constraining EDE-like models with higher preferred values of Ω
m
, as preferred by Pantheon+, reducing the allowed parameter space for H
0 values greater than 70 km s-1Mpc-1.
Drying trend in land and sea in East Asia during the warm season over the past four decades
Authors: Kim Go-Un , Oh Hyoeun , Jeong Jin-Yong
Published: October 2024

The East Asian region is typically characterized by warm and humid conditions from late spring to summer. However, in recent decades, this region has experienced an increase in severe drying conditions, deviating from historical climatological patterns. This study investigated the precipitation − evaporation (P − E) trends across land and sea regions in East Asia (EA) during the extended summer season (April–September) from 1980 to 2022, and the key physical processes driving these trends through moisture budget decomposition and numerical experiments. The results reveal pronounced drying trends in southeastern China and the Yellow Sea and parts of the Korea Strait and Korean Peninsula over the past 43 years. The underlying physical processes driving these drying conditions differ between land and sea in EA. In southeastern China, the drying is driven by dynamic processes, particularly moisture divergence related to wind changes. This is linked to anomalous strengthening of descending motion due to the Indo-Pacific warm pool warming induced by both anthropogenic global warming and natural Pacific Decadal Oscillation-like sea surface temperature (SST) patterns. Conversely, drying in the Yellow Sea and adjacent areas is influenced by thermodynamic moisture advection. The altered humidity distribution due to global warming-induced SST patterns, which are higher over the Northwest Pacific marginal sea and lower in inland China, drives dry air transport from inland China to the Yellow Sea via background southwesterly wind. These findings enhance our understanding of the drying trend and their distinct processes in EA’s land and sea areas during the extended summer.
HELGA: a global hydro-economic model of groundwater-fed irrigation from a farmer’s perspective
Authors: Melo-León Sioux F , Reinhard Stijn , Bierkens Marc F P , van Beek Rens
Published: October 2024

Overexploitation of groundwater for irrigation can ultimately threaten the viability of agriculture itself, because the falling groundwater levels become too deep to sustain the increasing costs of groundwater extraction, an economic limit is reached. In order to evaluate possible adaptation strategies to avoid or postpone reaching the economic limit, we developed the microeconomic heuristic model HELGA (hydro-economic limits as a global analysis). HELGA considers the interaction of groundwater with irrigation at the farm level with a global scale application in mind. HELGA evaluates the development of the costs and revenue of groundwater-fed irrigated agriculture from the farmer’s perspective. As long as the farm remains economically viable, the farmer can invest to access deeper groundwater, but in the long run the famer may have to adapt to keep farming profitable. We applied HELGA in five locations within the conterminous USA. In most cases, recharge is large enough to save a farmer from reaching the economic limit. Where groundwater is overexploited, the increasing energy cost of groundwater pumping is one of the main drivers limiting groundwater use. Additionally, the increasing costs of the water infrastructure (i.e. deeper wells) is a crucial factor that explains where and when the economic limit is reached. If farmers change crops wisely or fallow part of their land, they are able to access groundwater longer and postpone the moment the economic limit is reached. Using HELGA, we show that proper and timely adaptation measures increases the profitable lifetime of groundwater and helps to conserve this resource for future generations.
Protecting the environment at home or abroad?
Authors: Presberger David , Kolcava Dennis , Bernauer Thomas
Published: October 2024

By importing goods whose production affects the environment abroad, wealthy countries are ‘offshoring’ a large share of their total environmental footprint of consumption to less affluent societies. We argue that current efforts to mitigate this problem, which focus largely on informational policy instruments for global supply chains, could result in unintended side effects. The reason pertains to a potential tradeoff between a home bias in consumption and the geographic allocation of environmental impacts. We develop a theoretical argument on how consumers may respond when they prefer a domestically produced good but are made aware that this results in more environmental damage at home, compared to importing the same product from abroad. Based on choice experiments in Germany, Japan, and the United States, we observe that information provision can reduce consumer demand for environmentally harmful products, but also find some support for environmental NIMBYism when environmental and provenance information are combined. The key implication of this finding is that policymakers should address potentially unintended side-effects of more stringent informational requirements for global supply chains.
Plaquette models, cellular automata, and measurement-induced criticality
Authors: Liu Hanchen , Chen Xiao
Published: October 2024

We present a class of two-dimensional randomized plaquette models, where the multi-spin interaction term, referred to as the plaquette term, is replaced by a single-site spin term with a probability of

1
−
p

. By varying p, we observe a ground state phase transition, or equivalently, a phase transition of the symmetry operator. We find that as we vary p, the symmetry operator changes from being extensive to being localized in space. These models can be equivalently understood as 1+1D randomized cellular automaton dynamics, allowing the 2D transition to be interpreted as a 1+1D dynamical absorbing phase transition. In this paper, our primary focus is on the plaquette term with three or five-body interactions, where we explore the universality classes of the transitions. Specifically, for the model with five-body interaction, we demonstrate that it belongs to the same universality class as the measurement-induced entanglement phase transition observed in 1+1D Clifford dynamics, as well as the boundary entanglement transition of the 2D cluster state induced by random bulk Pauli measurements. This work establishes a connection between transitions in classical spin models, cellular automata, and hybrid random circuits.
Stochastic bra-ket interpretation of quantum mechanics
Authors: Öttinger Hans Christian
Published: October 2024

The stochastic nature of quantum mechanics is more naturally reflected in a bilinear two-process representation of density matrices rather than in squared wave functions. This proposition comes with a remarkable change of the entanglement mechanism: entanglement effects do not originate from superpositions of wave functions, but they result from the bilinear structure of density matrices. Quantum interference appears as a multiplicative phenomenon rather than an additive superposition mechanism. We propose two general requirements such that the bilinear representation of density matrices is given in terms of two uniquely defined, identically distributed, Markovian stochastic jump processes. These general ideas are illustrated for the Einstein-Podolsky-Rosen and double-slit experiments. The expression of the stochastic nature of quantum mechanics in terms of random variables rather than their probability distributions facilitates an ontological viewpoint and leads us to a bra-ket interpretation of quantum mechanics.
Lightweighting cost impacts on market adoption and GHG emissions in U.S. light-duty vehicle fleet
Authors: Yang Fan , Brooker Aaron , Kleinbaum Sarah , Gotthold David
Published: October 2024

Vehicle lightweighting is a promising strategy that can reduce energy consumption and GHG emissions without compromising vehicle’s performance or size. The cost of lightweighting plays a critical role in determining the adoption of lightweighting technologies by consumers and manufacturers among advanced vehicle technologies. This analysis estimates the cost of lightweighting needed to achieve significant light-duty vehicle adoption to provide reductions in use-phase GHG emissions. Three different costs of lightweighting scenarios in the U.S. market including a baseline scenario, advanced technology scenario, and widespread scenario are evaluated employing Automotive Deployment Options Projection Tool (ADOPT) in conjunction with other technology improvement assumptions (e.g., advancements in fuel and battery technologies, and material price reductions) from DOE. ADOPT leverages a database of over 700 existing vehicle models and options, enabling it to provide a high degree of realism and capture the unique characteristics of popular vehicles and the endogenously evolvement of the vehicle options. For baseline scenario, the use-phase GHG emissions are reduced by more than 50% and lightweighting fraction reaches 15% by 2046 compared to 2015 levels. The widespread scenario further reduces the GHG emissions by about 4% from the additional 10% glider mass reduction compared to the baseline scenario. The benefit came largely from lightweighting being implemented in the large market segment of lower-price vehicles, due to the relatively low lightweighting cost ($5/kg).
Optical wavefront shaping in deep tissue using photoacoustic feedback
Authors: Xia Fei , Leite Ivo , Prevedel Robert , Chaigne Thomas
Published: October 2024

Over the past decade, optical wavefront shaping has been developed to focus light through highly opaque scattering layers, opening new possibilities for biomedical applications. To probe light intensity deep inside soft scattering media such as biological tissues, internal guide-stars are required. Here, we give an overview of the main principles and describe in depth the use of a photoacoustic feedback signal for this purpose. We further present first principles calculations and simulations to estimate important experimental parameters, and detailed instructions on designing and conducting these experiments. Finally, we provide guidance towards selecting suitable equipment for building a typical experimental setup, paving the way for further innovative biomedical imaging and therapy applications.
Leveraging wearable sensors and machine learning for posture-based detection of carpal tunnel syndrome
Authors: Gautam Nikita , Gupta Sunil Kumar , Shrivastava Amit
Published: October 2024

Carpal tunnel is associated with long-term use of the wrist and hand for various activities such as typing, welding, or poor working postures. Carpal Tunnel Syndrome (CTS) may cause severe pain and discomfort in the hand and wrist, and in some circumstances, surgery becomes inevitable. The objective of this study is to prevent typing postures, which can be ascertained as predisposing subjects to CTS development. The data used in this study is an array of wrist wearable sensors to capture flexion, extension, and bending of fingers while using a keyboard or mouse. Machine learning is employed on the data in order to identify risk factors indicative of a high probability of CTS. The analyzed models are linear regression, Support Vector Machine, Random Forest, Multilayer Perceptron, Convolution Neural Network, and Long Short Term Memory. The conditions for assessing the performance of the data models include RMS error, coefficients of determination, and mean absolute percentage error. In this research, I conducted an exploratory data analysis (EDA) to gain an initial understanding of the dataset. Following the exploratory phase, I applied feature extraction techniques, specifically Principal Component Analysis (PCA). As put forward for the proposed research, the strategies to prevent risky occupations have broad potential at the present time, especially in the case of CTS when preventing repetitive wrist movements.
Regulating Rivalry
Authors: Beitz Charles R
Published: October 2024

The second lecture begins by drawing lessons about democratic representation from the intimations of failure canvassed in the first lecture. It goes on to sketch a normative conception of democratic representation as a properly regulated competitive system. The basic idea is that competition is a distinctive means of solving problems that depends on its participants conducting themselves as adversaries. We rely on competition to produce social value. The problem is that, if not properly regulated, political competition can run off the rails, defeating its social purposes. A central problem for a theory of democratic representation is to identify the purposes we rely on political competition to produce and the arenas in which competition can produce them. The lecture notes four such purposes: to produce policy responsive to the settled will of the majority; to avoid predictable forms of substantive injustice; to resolve conflict effectively, at least insofar as it pertains to broadly valued public functions; and to maintain deliberative environments in both the institutional and public spheres conducive to epistemically responsible judgment by public officials and citizens. The purposes can be realized in different ways and to different extents in the various competitive arenas that make up the system. To illustrate, we consider three arenas of competition—electoral competition, party competition, and interest competition—and ask what it would mean for competition in these arenas to be fairly regulated. It emerges that well-regulated competition among healthy political parties is a necessary condition of fair and effective representation.
Intimations of Failure
Authors: Beitz Charles R
Published: October 2024

In the last few decades, many professional observers of American politics have worried that the constitutional system of democratic representation is failing. The convergence on intimations of failure is my starting point. It raises first-order normative concerns about the health of democratic representation in America that should worry all of us. The convergence also raises more theoretical questions about the nature and aims of democratic representation or, as I put it here, about standards of fair and effective representation. The first lecture begins by noting some stylized facts that purport to describe shortfalls from democratic representation. These include the phenomena of legislative gridlock, partisan polarization, unequal responsiveness by class and race, and partisan bias in legislative districting. Reflecting on these phenomena, I distinguish several kinds of failures that they implicate: of effectiveness, of congruence and responsiveness, and of fairness. In each case my aim is to grasp the normative grounds of judgments of failure explicit or implicit in the empirical literatures. On inspection, we see that the judgments of failure appeal to several distinct considerations of democratic political morality. It is difficult to see how these considerations might be brought within a single perspective that can make sense of them all. This prepares the way for the second lecture, where I try to sketch one way we might construct such a perspective.
Setting History in Motion
Authors: McDonald Daniel
Published: October 2024

This article examines the video essay in this issue, “Visualizing Resilience from the Periphery: Social Movements, Visual Archives, and the Megacity,” and the video essay as a form of historical argumentation. First, the article traces how the video essay reconstructs a visual lexicon that fostered resilience among social movements from the urban peripheries of South America’s most populous city, São Paulo, during Brazil’s civil-military dictatorship (1964–85) and the democratic transition that followed. Popular artists illustrated movement paraphernalia with hand-drawn images of diverse subjects, including urban landscapes, public life, neighborhood organizing, and open protest. The video essay assembles these dispersed illustrations as well as soundscapes and clips from films into distinct phases of a metanarrative connecting the rise of the megacity to collective social action. It subsequently disassembles those focal points to underscore the open-ended and iterative nature of visual argumentation. The article then underscores how the video essay as a form of peer-reviewable argumentation allows historians to creatively engage with a large corpus of visual imagery. It concludes by discussing issues inherent to the form, such as the difference between written and visual argumentation, citation practices, integration of text, translation of foreign languages, and the preservation of digital scholarship, among others.
Calcium Hydroxylapatite in Regenerative Aesthetics: Mechanistic Insights and Mode of Action
Authors: van Loghem Jani
Published: October 2024

Calcium hydroxylapatite–carboxymethylcellulose (CaHA-CMC) is a widely utilized soft tissue filler known for its compatibility with human tissue and for its effective volumizing properties. The biodegradable CaHA microspheres function as a scaffold for the formation of new tissue by stimulating a variety of cellular responses leading to the production of collagen, elastin, vasculature, and proteoglycans and thereby enhance skin quality. Despite the promising regenerative effects of CaHA-CMC, substantial gaps remain in understanding its precise underlying mechanisms, and addressing these gaps is crucial to optimizing its clinical applications. A literature search was conducted with PubMed, Google Scholar, and Web of Science for keywords, including “calcium hydroxylapatite,” “tissue regeneration,” “macrophages,” “fibroblasts,” and “calcium.” This review elucidates the novel mechanisms of CaHA-CMC action within aesthetic medicine, with a focus on the dynamic interactions between macrophages and fibroblasts. The key role of calcium ions as critical biological cues in directing skin regeneration pathways is explored alongside an examination of the distinct physicochemical properties of CaHA-CMC. CaHA-CMC helps in tissue regeneration by providing calcium ions that act as key biological cues, promoting fibroblast activity and collagen production.
Racial and Ethnic Disparities in Hepatitis C Care in Reproductive-Aged Women With Opioid Use Disorder
Authors: Biondi Breanne E , Munroe Sarah , Lavarin Claudine , Curtis Megan R , Buzzee Benjamin , Lodi Sara , Epstein Rachel L
Published: October 2024

Background

In the United States, hepatitis C virus (HCV) diagnoses among reproductive-aged women are increasing amidst the ongoing opioid and drug overdose epidemic. While previous studies document racial and ethnic disparities in HCV testing and treatment in largely male populations, to our knowledge no national studies analyze these outcomes in reproductive-aged women with opioid use disorder (OUD).

Methods

We analyzed data from a cohort of reproductive-aged women (aged 15–44 years) with diagnosed OUD captured in the TriNetX Research Network, a network of electronic health records from across the United States. Using a log-binomial model, we assessed differences in achieving HCV cascade of care stages (HCV antibody testing, HCV infection [positive HCV RNA test result], linkage to care, and HCV treatment) by race and ethnicity.

Results

From 2014 to 2022, 44.6% of the cohort were tested for HCV antibody. Asian and black/African American individuals had a lower probability of having an HCV antibody test than white individuals (risk ratio, 0.77 [95% confidence interval, .62–.96] and 0.76 [.63–.92], respectively). Among those with HCV infection, only 9.1% were treated with direct-acting antivirals. Hispanic/Latinx individuals had a higher probability of treatment than non-Hispanic/Latinx individuals (risk ratio, 1.63 [95% confidence interval, 1.01–2.61]).

Conclusions

Few reproductive-aged women with OUD are tested or treated for HCV. Disparities by race and ethnicity in HCV testing further exacerbate the risk of perinatal transmission and disease progression among minoritized communities. Interventions are needed to improve overall rates of and equity in HCV screening and treatment for reproductive-aged women.
A-347 A Comprehensive Exdia TRF-LFIA for Simultaneous Quantification of GFAP and NT-proBNP in Distinguishing Ischemic and Hemorrhagic Stroke
Authors: Sayyed D R , Lee M , Hong S , Kim H , Kim H , Sanchez J , Choi S , Han E , Kang H , Kim J , Joan M , Kim H , Chae H , Park J
Published: October 2024

Background

The goal of this study is to create a highly sensitive time-resolved fluorescence lateral flow immunoassay (TRF-LFIA) capable of concurrently measuring glial fibrillary acidic protein (GFAP) and the N-terminal fragment of B-type natriuretic peptide precursor (NT-proBNP). This assay is designed as a diagnostic tool and aims to provide an algorithm for stroke management, specifically for distinguishing between Ischemic stroke (IS) and Hemorrhagic stroke (HS). However, LFIA to quantify simultaneous serum NT-proBNP and GFAP are not yet available.

Methods

We have developed and validated a novel TRF-LFIA for the simultaneous quantitative detection of NT-proBNP and GFAP. The sensitivity and reproducibility of the immunoassay were significantly improved by employing specific monoclonal antibodies linked to europium nanoparticles (EuNPs) that specifically target NT-proBNP and GFAP. The detection area on the nitrocellulose membrane featured sandwich-style complexes containing three test lines for NT-proBNP, GFAP, and Control. The fluorescence intensity of these test lines on the nitrocellulose membrane was measured using an in-house developed Exdia TRF-Plus analyzer. As proof-of-concept, we enrolled patients suspected of having a stroke who were admitted within a specific time frame (6 hours). A small amount of clinical specimen (serum) was used with a well-assembled cartridge for the measurement of GFAP and NT-proBNP.

Results

To optimize the LFIA, an EuNPs conjugated antibodies were investigated to improve the detection sensitivity and decrease the background signal as well shorten the detection time. The Exdia TRF-LFIA cartridge offers a wide linear dynamic detection range, rapid detection, high sensitivity, and specificity. The limit of detection was determined to be 98 pg/mL for NT-proBNP and 68 pg/mL for GFAP, with minimal cross-reactivity. There were 200 clinical human serum samples that were used to evaluate this platform with high correlation. By combining the results of NT-proBNP and GFAP, we formulated an algorithm for the clinical assessment of Ischemic Stroke (IS) and Hemorrhagic Stroke (HS). According to our proposed algorithm, the combination of GFAP and NT-proBNP emerged as the most effective biomarker combination for distinguishing between IS and HS.

Conclusions

Exdia TRF-LFIA shows great potential as a supplemental method for in vitro diagnostics in the laboratory or in other point-of-care testing (POCT) applications. Its development substantially decreases the diagnosis time for IS and HS. The proposed algorithm not only minimizes treatment delays but also lowers medical costs for patients.
A-368 Feasibility of a Five-Minute Sample-to-Answer Basic Metabolic Panel for Point-of-Care Testing on the Fluxergy Analyzer
Authors: Charrault E , Zhen X , Dumitrescu E , Prakash P , Pineda E , Caron D , Hernandez B , Lamberg P , Sathyamoorthy K , Gandhi S , Singh A , Patel T , Heltsley R
Published: October 2024

Background

Adoption of point-of-care (POC) platforms has been limited by their high cost and limited menu (e.g., molecular only). Fluxergy has developed a cost-effective multimodal POC platform capable of performing the most common clinical chemistry, immunochemistry, hematology, molecular tests in CLIA-waived settings. This method comparison study describes the performance of the Fluxergy’s feasibility stage basic metabolic panel (BMP) with contrived samples compared to the Siemen’s epoc® Blood Analysis System.

Methods

Fluxergy Analyzer: The Fluxergy Analyzer is a rapid and cost-effective multimodality platform that can perform lab-quality PCR, clinical chemistry, immunochemistry, and cytometry in a single instrument and if required, in a single cartridge. Fluxergy BMP: Fluxergy BMP rapidly quantifies key electrolytes (K+, Na+, Ca2+, Cl-) and metabolites (glucose, creatinine, and BUN) from whole blood in under five minutes on the Fluxergy Analyzer, utilizing the Fluxergy test cards with screen-printed electrochemical sensor. Feasibility Study: A method comparison study was conducted to assess the performance of the feasibility stage Fluxergy BMP using contrived samples generated by spiking known concentrations of K+, Na+, Ca2+, Cl-, and glucose into buffer solutions. Samples were tested in triplicate with both the Fluxergy BMP and Siemen’s epoc® Blood Analysis System at three different concentrations across the reportable range of the epoc® Blood Analysis System.

Results

The feasibility stage Fluxergy BMP demonstrated strong correlation across the reportable range for K+, Na+, Ca2+, Cl-, and glucose versus the epoc® Blood Analysis System (Table 1). The error percentage for all samples tested except one glucose sample (9.5 mM) was less than 10%. The coefficient of variance for all samples tested except one Ca2+ sample (0.44 mM) was less than ten percent.

Conclusions

This feasibility data demonstrates the Fluxergy Analyzer is well-suited to perform rapid and accurate metabolic testing from whole blood samples at the POC.
Trends, prescribing patterns, and determinants of initial antiepileptic drug treatment in older epileptic patients
Authors: Singkham Noppaket , Saiwijit Pitsamai , Sangliamthong Papavee , Panthong Tawanrat , Wiangkham Hataikan
Published: October 2024

Objectives

There is no report on the initial antiepileptic drug (AED) treatment of older Thai epileptic patients. This study aimed to determine the trends, prescribing patterns, and determinants of initial AED treatment.

Methods

This cross-sectional study used data on older (≥60 years) epileptic patients gathered from one tertiary-care hospital’s database from 2012 to 2022. We evaluated the trends and prescribing patterns for starting AED treatment. We used logistic regression to identify the determinants of the initial treatment with new-generation AEDs.

Key findings

This study comprised 919 participants (59.19% men, 70.99 ± 8.00 years old). Between 2012 and 2022, we observed a decreasing trend in starting therapy with old-generation AEDs, from 89.16% to 64.58%. In contrast, there was an increasing trend in initiating treatment with new-generation AEDs, from 10.84% to 35.72% (P for trend <0.001 for both). Each assessment year, the most prescribed treatment pattern was monotherapy. The determinants of initial therapy with new-generation AEDs included the year treatment began (adjusted odds ratios [AOR] = 1.0006; 95% confidence intervals [CI] 1.0003–1.0008), non-Universal Coverage Scheme (AOR = 1.94; 95% CI 1.26–3.00), liver disease (AOR = 6.44; 95% CI 2.30–18.08), opioid use (AOR = 2.79; 95% CI 1.28–6.09), and statin use (AOR = 0.59; 95% CI 0.36–0.95).

Conclusions

There is a growing trend of initiating treatment with new-generation AEDs in older Thai patients with epilepsy. Factors positively associated with starting new-generation AEDs include the year treatment began, non-Universal Coverage Scheme, liver disease, and opioid use, while statin use is a negatively associated factor.
Epigenetic Changes in Cerebrospinal Fluid and Blood of People With Neurosyphilis
Authors: Mostaghimi Darius , Mehta Sameet , Yoon Jennifer , Kosana Priya , Marra Christina M , Corley Michael J , Farhadian Shelli F
Published: October 2024

Epigenetic changes within immune cells may contribute to neuroinflammation during bacterial infection, but their role in neurosyphilis (NS) pathogenesis and response has not yet been established. We longitudinally analyzed DNA methylation and RNA expression in cerebrospinal fluid (CSF) cells and peripheral blood mononuclear cells (PBMCs) from 11 participants with laboratory-confirmed NS (CSF Venereal Disease Research Laboratory test positive) and 11 matched controls with syphilis without NS (non-NS). DNA methylation profiles from CSF and PBMCs of participants with NS significantly differed from those of participants with non-NS. Some genes associated with these differentially methylated sites had corresponding RNA expression changes in the CSF (111/1097 [10.1%]), and included genes involved in B cell activation and insulin-response pathways. Despite antibiotic treatment, approximately 80% of CSF methylation changes associated with NS persisted, suggesting that epigenetic scars accompanying NS may persistently affect immunity following infection. Future studies must examine whether these sequelae are clinically meaningful.
ATP promotes protein coacervation through conformational compaction
Authors: Zhu Yueling , Lin Shiyan , Meng Lingshen , Sun Min , Liu Maili , Li Jingyuan , Tang Chun , Gong Zhou
Published: October 2024

ATP has been recognized as a hydrotrope in the phase separation process of intrinsically disordered proteins (IDPs). Surprisingly, when using the disordered RG/RGG-rich motif from HNRNPG protein as a model system, we discover a biphasic relationship between the ATP concentration and IDP phase separation. We show that at a relatively low ATP concentration, ATP dynamically interacts with the IDP, which neutralizes protein surface charges, promotes intermolecular interactions, and consequently promotes phase separation. We further demonstrate that ATP induces a compact conformation of the IDP, accounting for the reduced solvent exchange rate and lower compression ratio during phase separation. As ATP concentration increases, its hydrotropic properties emerge, leading to the dissolution of the phase-separated droplets. Our finding uncovers a complex mechanism by which ATP molecules modulate the structure, interaction, and phase separation of IDPs, and accounts for the distinct phase separation behaviors for the charge-rich RGG motif and other low-complexity IDPs.
The necessity of individually validated beam models for an interferometric epoch of reionization detection
Authors: Chokshi A , Barry N , Line J L B , Jordan C H , Pindor B , Webster R L
Published: October 2024

A first statistical detection of the 21-cm Epoch of Reionization (EoR) is on the horizon, as cosmological volumes of the Universe become accessible via the adoption of low-frequency interferometers. We explore the impact which non-identical instrumental beam responses can have on the calibrated power spectrum and a future EoR detection. All-sky satellite measurements of Murchison Widefield Array (MWA) beams have revealed significant sidelobe deviations from cutting-edge electromagnetic simulations at the ${\sim} 10~{{\ \rm per\ cent}}$ zenith power level. By generating physically motivated deformed beam models, we emulate real measurements of the MWA which inherently encode the imprints of varied beams. We explore two calibration strategies: using a single beam model across the array, or using a full set of deformed beams. Our simulations demonstrate beam-induced leakage of foreground power into theoretically uncontaminated modes, at levels which exceed the expected cosmological signal by factors of over $\sim$1000 between the modes k = 0.1–1 $h\mathrm{Mpc}^{-1}$. We also show that this foreground leakage can be mitigated by including measured models of varied beams into calibration frameworks, reducing the foreground leakage to a sub-dominant effect and potentially unveiling the EoR. Finally, we outline the future steps necessary to make this approach applicable to real measurements by radio interferometers.
A network of cooler white dwarfs as infrared standards for flux calibration
Authors: Elms Abbigail K , Gentile Fusillo Nicola Pietro , Tremblay Pier-Emmanuel , Bohlin Ralph C , Hollands Mark A , Sahu Snehalata , O’Brien Mairi W , Deustua Susana , Cunningham Tim
Published: October 2024

The accurate flux calibration of observational data is vital for astrophysics and cosmology because absolute flux uncertainties of stellar standards propagate into scientific results. With the ever higher precision achieved by telescopic missions (e.g. JWST) in the infrared (IR), suitable calibrators are required for this regime. The basis of the Hubble Space Telescope (HST) flux scale is defined by model fits of three hot (${T_\mathrm{eff}} > 30\, 000$ K) hydrogen-atmosphere (DA) white dwarfs, which achieve an accuracy better than 1 per cent at optical wavelengths but falls below this level in the IR range. We present a network of 17 cooler DA white dwarfs with ${T_\mathrm{eff}} < 20\, 000$ K as spectrophotometric flux standards that are equally, if not more, accurate at IR wavelengths. Cooler white dwarfs do not suffer from non-local thermal equilibrium effects in continuum flux or from ultraviolet metal line blanketing, have a larger sky density, are generally closer to Earth with little or negligible interstellar reddening, and have energy distributions peaking in the optical or near-IR. Using the latest grid of DA local thermal equilibrium atmosphere models with three-dimensional convection, the observed Space Telescope Imaging Spectrometer (STIS) and Wide Field Camera 3 (WFC3) fluxes of our network are accurate to 3 per cent over most of the range $1450\!\! - \!\!16\, 000$ Å, with a median standard deviation of 1.41 per cent. Fitting the HST STIS and WFC3 white dwarf spectral energy distributions (SEDs) and Balmer lines independently yields SEDs that agree within $3\sigma$, which demonstrates the precision of the models for our network.
LGGL-01 “INTERVENTION OUTCOMES OF ENHANCED RECOVERY AFTER SURGERY PROTOCOL VERSUS STANDARD CARE FOR GLIOMA PATIENTS IN SELECTED HOSPITALS IN DEMOCRATIC REPUBLIC OF THE CONGO: RANDOMIZATION AND STRATIFICATION OF PROVIDERS AND HOSPITALS”
Authors: Kamabu Larrey Kasereka , Glennie Ntsambi
Published: October 2024

Enhanced Recovery after Surgery (ERAS) protocols aim to improve perioperative care and patient outcomes. A pragmatic, multicenter, randomized controlled trial will be conducted in the Democratic Republic of Congo (DRC) to assess ERAS’ efficacy compared to the current standard of care (SOC) for glioma patients. Eligible providers will be randomized at the surgical team level to ERAS or SOC, ensuring consistent practices within teams. Hospitals representing diverse healthcare settings will be included, and randomization will be stratified by hospital to ensure balance. 100 glioma patients (50 in each group) will be included, and primary analysis expects fewer post-operative complications and shorter hospital stays in the ERAS group, with higher patient satisfaction. Subgroup analyses will be conducted by hospital center. Randomization and stratification aim to mitigate provider and hospital-specific influences, enhancing the study’s validity and equitable representation. This unique trial design seeks to provide insights into ERAS benefits for glioma patients in resource-constrained settings, guiding clinical practice and healthcare policy to improve care and outcomes.
MNGA-04 SOCIOECONOMIC DISPARITIES IN ACCESS TO SUBSPECIALTY CARE FOR MENINGIOMA PATIENTS: A LITERATURE REVIEW
Authors: Chiromo Mutsa , Fatade Eniola , Fonkem Ekokobe
Published: October 2024

Meningiomas, the most prevalent brain tumors, constitute nearly 40% of all head tumors, with the majority being benign. Presenting symptoms vary widely, including headaches, vision changes, seizures, and extremity weakness. Given the frequency of meningiomas and their diverse symptoms, access to subspecialty care is crucial for determining treatment necessity. However, existing global healthcare disparities often limit access to the necessary subspecialty care for addressing meningiomas. This literature review investigates the impact of socioeconomic disparities on neuro-oncologic care access, drawing from retrospective cohort studies and multi-cohort analyses. PubMed was utilized to search for articles published between 2000 and 2024, focusing on the relationship between socioeconomic status (SES) and care access, treatment, and outcomes among meningioma patients. Demographic analyses across studies revealed disparities in access to care across age groups, from young adults (20-39 years old) to the elderly (60 years and older). Additionally, disparities were noted among racial and ethnic groups, including African American, Hispanic, and Caucasian populations. Geographic disparities were also evident, with studies spanning regions within the United States and globally, underscoring variations in healthcare access and outcomes. Findings consistently emphasized the disproportionate burden borne by individuals from lower SES backgrounds, characterized by delayed diagnosis, limited treatment options, and poorer survival rates compared to their higher SES counterparts. Structural barriers, such as inadequate health literacy, limited insurance coverage, and geographical constraints, were significant contributors to these disparities, perpetuating health inequities among meningioma patients. Addressing disparities requires comprehensive interventions, including policy reforms to improve insurance coverage, enhance specialist access, and promote culturally sensitive care. Prioritizing initiatives targeting socioeconomic barriers ensures equitable care for all meningioma patients. In conclusion, concerted efforts at all levels are needed to dismantle structural barriers and foster equitable healthcare access and delivery.