bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineered Substrates for Controlling Cell-Cell Interactions
Authors: Bhatia Sangeeta N. , Yarmush Martin L. , Toner Mehmet
Published: September 2024

Biomaterials have been previously engineered to serve a variety of different functions: precise degradation in vivo (Kimura, 1993), modulation of cell physiology via binding to specific ligands (Hubbell et al, 1992), and selective permeability of certain solutes (Lysaght et al, 1994). However, in complex tissues, where cell-cell interactions strongly influence tissue function, biomaterials which modulate this fundamental parameter have not been available. In this study, we describe a technique which allows control over cell-cell interactions by using semiconductor-based microfabrication, silane derivatization of borosilicate, and immobilization of specific biomolecules. We have focused on liver tissues due to the clinical significance of liver disease and the potential utility of a highly functional in vitro substitute for the liver (Rozga et al, 1994). Previous studies have reported that co-culture of primary hepatocytes with mesenchymal cells induces up-regulation of liver-specific functions in the hepatocyte population (Guguen-Guillouzo et al, 1983). Using microfabricated techniques to pattern co-cultures, we have demonstrated the importance of local cell-cell interactions in overall tissue function. Specifically, we show that the level of heterotypic interaction modulates the kinetics of up-regulation of liver-specific functions when compared to unpatterned controls. This approach will have applications in many areas including tissue engineering, developmental biology, and transplantation.
Determination of the Safe Touch Temperature for Various Surface Configurations and Materials
Authors: Subramanian Balakrishnan , Chato John C.
Published: September 2024

A finite difference heat transfer model has been developed to predict the Safe Touch Temperatures of objects with different material and geometric properties. The uncertainties in the physiological and thermal properties of human skin and tissue are accounted for by making conservative assumptions in the model. The damage function criteria developed by Henriques and Moritz are used to quantify thermal injury. The results indicate a strong dependence of Safe Touch Temperatures on the thickness dimension of the material, in addition to it’s thermal properties.
Finite-Element Codes to Model Electrical Heating and Non-Linear Thermal Transport in Biological Media
Authors: Humphries Stanley , Platt Robert C. , Ryan Thomas P.
Published: September 2024

ETherm is a versatile finite-element software system to model heating in biological media for electrosurgery and other medical applications. The electrical field component calculates penetration of RF radiation into conductive dielectrics. The thermal solver finds time-dependent or steady-state solutions using stable diffusion methods with automatic time step adjustment. An important feature is the capacity to treat non-linear diffusion with temperature-dependent thermal properties such as blood perfusion to represent physical changes of tissues. The program also evaluates Arrhenius damage integrals by maintaining temperature integrals over tissue elements.
Estimation of Blood Perfusion Using a Minimally Invasive Blood Perfusion Probe
Authors: Scott Elaine P. , Robinson Paul , Diller Thomas E.
Published: September 2024

This work is part of an ongoing research effort in which parameter estimation techniques have been utilized in the noninvasive measurement of blood perfusion using measurements from a new surface probe. The key element of the probe is a sensor which provides time-resolved signals representing heat flux and temperature. The probe incorporates a thin sensor, which is placed in contact with the tissue. For safety reasons no electric power or heating is applied to the probe; its low level signals are generated by the small temperature difference produced by air cooling. The probe is placed directly on the surface of the skin, and both temperature and heat flux are measured simultaneously at the surface while the probe is cooled by air jets. The small, light-weight probe can be taped to the skin, much like a surface electrode, for repeated measurements. A combination of analytical and experimental methods is being used for the development of the measurement system. A mathematical model of the probe and tissue during operation was developed previously to calculate temperature and heat flux at the surface of the skin. The design of the probe was first optimized using this model to maximize the sensitivity of the data for the determination of blood perfusion. Parameter estimation techniques were then developed to estimate blood perfusion and also the thermal contact resistance between the probe and the tissue. Here, both measured data and corresponding calculated data from the model are incorporated into an objective function which is minimized to simultaneously estimate the unknown properties. A probe of optimum design is being constructed and will be tested with appropriate phantoms. The final goal of this research is to develop a practical, noninvasive probe that will be clinically useful in the determination of blood perfusion.
Design, Analysis, and Optimization of Composite Leaf Springs for Light Vehicle Applications
Authors: Gratton Mathieu , Sancaktar Erol
Published: September 2024

Design and manufacture of a functional composite spring for a solar powered light vehicle is described. The objective is not to compare composite spring systems using different types of springs such as rubber disks, air shocks, etc., but to provide an understanding of the manufacture, use, and capabilities of composite leaf springs produced by using unidirectional E-glass roving impregnated by an epoxy resin for light vehicle applications where the vehicle weight is of primery concern. The current design application involves a solar powered car.
Finite Element Contact, Stress and Strain Analysis of a Composite Fibre-Matrix Micro System Subjected to Ball Indentation
Authors: Váradi Károly , Néder Zoltán , Friedrich Klaus , Flöck Joachim
Published: September 2024

The presented FE contact technique is applied to the problem of a steel ball indented into a composite material consisting of unidirectional continuous carbon fibres in a polyetheretherketone matrix. Indentation was carried out with fibre orientations either normal (N) or parallel (P) to the contact surface at fiber volume fraction 44%.

The FE contact stress analysis of a fibre/matrix micro structure has some strong limitations. If FE micro models are used, only a very small (for example 0.1 × 0.1 × 0.1 mm) 3D segment can be modelled while the number of degrees of freedom (DOF) is immediately in the range of 100.000. If anisotropic numerical models are used, there are no size limitations but the results can not describe the stress and strain states of a real fibre/matrix micro structure.

The FE contact analysis involves both an anisotropic (homogeneous) macro and (inhomogeneous) micro contact analysis, following an approximate displacement coupling technique. This technique considers only the displacements along the coupled surfaces. The coupled solution provides a more realistic elastic deformation, stress and strain results of the composite micro system in the vicinity of the contact area, and at the same time the effect of the macro system is also incorporated.

The FE contact results show the location and the distribution of the subsurface stresses and strains. For N fibre orientation there is a high shear stress region below the surface, from where the fibre/matrix interfacial failure initiates before propagation to the surface. These results are in good agreement with experimental results published in the open literature. In case of P fibre orientation the matrix is subjected to local plastic deformation while the characteristic deformation of the fibre is bending.
The Damping Characteristics of a Cantilever Structure With a Lap-Type Adhesive Joint
Authors: Kobayashi Takashi
Published: September 2024

The purpose of this paper is to clarify the damping characteristics of an adhesively bonded structure and to establish a method to estimate the damping capacity. As a fundamental study, a cantilever structure, in which one end of a beam is bonded to a relatively large base with a lap-type adhesive joint, is employed in this study. The damping capacity of the cantilever structure, which is vibrating in the directions vertical or tangential to the bonding surface, is investigated. Experimentally, a test rig, which corresponds to the analytical model, is manufactured and the damping capacity is measured. The analytical results are in fairly good agreement with the experimental ones. Furthermore, the damping capacity of the cantilever structure with a bolted joint is measured and is compared with those of the adhesive joint.
Combined assembloid modeling and 3D whole-organ mapping captures the microanatomy and function of the human fallopian tube
Authors: Crawford Ashleigh J. , Forjaz André , Bons Joanna , Bhorkar Isha , Roy Triya , Schell David , Queiroga Vasco , Ren Kehan , Kramer Donald , Huang Wilson , Russo Gabriella C. , Lee Meng-Horng , Wu Pei-Hsun , Shih Ie-Ming , Wang Tian-Li , Atkinson Mark A. , Schilling Birgit , Kiemen Ashley L. , Wirtz Denis
Published: September 2024

The fallopian tubes play key roles in processes from pregnancy to ovarian cancer where three-dimensional (3D) cellular and extracellular interactions are important to their pathophysiology. Here, we develop a 3D multicompartment assembloid model of the fallopian tube that molecularly, functionally, and architecturally resembles the organ. Global label-free proteomics, innovative assays capturing physiological functions of the fallopian tube (i.e., oocyte transport), and whole-organ single-cell resolution mapping are used to validate these assembloids through a multifaceted platform with direct comparisons to fallopian tube tissue. These techniques converge at a unique combination of assembloid parameters with the highest similarity to the reference fallopian tube. This work establishes (i) an optimized model of the human fallopian tubes for in vitro studies of their pathophysiology and (ii) an iterative platform for customized 3D in vitro models of human organs that are molecularly, functionally, and microanatomically accurate by combining tunable assembloid and tissue mapping methods.
Evaluation of the lithium resource in the Smackover Formation brines of southern Arkansas using machine learning
Authors: Knierim Katherine J. , Blondes Madalyn S. , Masterson Andrew , Freeman Philip , McDevitt Bonnie , Herzberg Amanda , Li Peng , Mills Ciara , Doolan Colin , Jubb Aaron M. , Ausbrooks Scott M. , Chenault Jessica
Published: September 2024

Global demand for lithium, the primary component of lithium-ion batteries, greatly exceeds known supplies, and this imbalance is expected to increase as the world transitions away from fossil fuel energy sources. High concentrations of lithium in brines have been observed in the Smackover Formation in southern Arkansas (>400 milligrams per liter). We used published and newly collected brine lithium concentration data to train a random forest machine-learning model using geologic, geochemical, and temperature explanatory variables and create a map of predicted lithium concentrations in Smackover Formation brines across southern Arkansas. Using these predicted lithium maps with reservoir parameters and geologic information, we calculated that there are 5.1 to 19 million tons of lithium in Smackover Formation brines in southern Arkansas, which represents 35 to 136% of the current US lithium resource estimate. Based on these calculations, in 2022, 5000 tons of dissolved lithium were brought to the surface within brines as waste streams of the oil, gas, and bromine industries.
A neural circuit for alcohol withdrawal–induced hyperalgesia in a nondependent state
Authors: Yang Xin-Lu , Gao Wei , Dong Wan-Ying , Zheng Changjian , Wang Sheng , Wei Hong-Rui , Luo Yanli , Zhang Zhi , Chen Yongquan , Jin Yan
Published: September 2024

Alcohol use disorder is highly prevalent worldwide, with characteristically severe pain sensitivity during withdrawal. Here, we established a mouse model of hyperalgesia during ethanol withdrawal (EW) before addiction to investigate the window for onset and underlying mechanisms. Viral tracing with in vivo microendoscopic and two-photon calcium imaging identified a circuit pathway from dorsal hippocampal CA1 glutamatergic neurons (dCA1
Glu
) to anterior cingulate cortex glutamatergic neurons (ACC
Glu
) activated in EW mice with hyperalgesia. Chemogenetic inhibition of this pathway can alleviate hyperalgesia in EW mice, whereas artificial activation recapitulates EW-induced hyperalgesia in naïve mice. These findings demonstrate that the dCA1
Glu
→ ACC
Glu
neuronal pathway participates in driving EW-induced hyperalgesia before ethanol dependence in mice.
Cold-induced degradation of core clock proteins implements temperature compensation in the
Arabidopsis
circadian clock
Authors: Maeda Akari E. , Matsuo Hiromi , Muranaka Tomoaki , Nakamichi Norihito
Published: September 2024

The period of circadian clocks is maintained at close to 24 hours over a broad range of physiological temperatures due to temperature compensation of period length. Here, we show that the quantitative control of the core clock proteins TIMING OF CAB EXPRESSION 1 [TOC1; also known as PSEUDO-RESPONSE REGULATOR 1 (PRR1)] and PRR5 is crucial for temperature compensation in
Arabidopsis thaliana
. The
prr5 toc1
double mutant has a shortened period at higher temperatures, resulting in weak temperature compensation. Low ambient temperature reduces amounts of PRR5 and TOC1. In low-temperature conditions, PRR5 and TOC1 interact with LOV KELCH PROTEIN 2 (LKP2), a component of the E3 ubiquitin ligase Skp, Cullin, F-box (SCF) complex. The
lkp2
mutations attenuate low temperature–induced decrease of PRR5 and TOC1, and the mutants display longer period only at lower temperatures. Our findings reveal that the circadian clock maintains its period length despite ambient temperature fluctuations through temperature- and
LKP2
-dependent control of PRR5 and TOC1 abundance.
ipolygrowth: an R package to calculate individual growth curve parameters from bacterial time series data
Authors: Wang Jifan , Barger Kathryn
Published: September 2024

The ipolygrowth package is a user-friendly tool that calculates growth curve parameters for time series data from microplate readers. Calculations are based on fourth-degree polynomial functions, which provide an alternative to commonly used sigmoidal models. The package is available for installation through the Comprehensive R Archive Network.
Cell wall nanoparticles from hyphae of
Alternaria infectoria
grown with caspofungin, nikkomycin, or pyroquilon trigger different activation profiles in macrophages
Authors: Antunes Daniela , Domingues Rita , Cruz-Almeida Mariana , Rodrigues Lisa , Borges Olga , Carvalho Agostinho , Casadevall Arturo , Fernandes Chantal , Gonçalves Teresa
Published: September 2024

Alternaria infectoria
causes opportunistic human infections and is a source of allergens leading to respiratory allergies. In this work, we prepared cell wall nanoparticles (CWNPs) as a novel approach to study macrophage immunomodulation by fungal hyphal cell walls.
A. infectoria
was grown in the presence of caspofungin, an inhibitor of β(1,3)-glucan synthesis; nikkomycin Z, an inhibitor of chitin synthases; and pyroquilon, an inhibitor of dihydroxynaphthalene (DHN)-melanin synthesis. Distinct CWNPs were obtained from these cultures, referred to as casCWNPs, nkCWNPs, and pyrCWNPs, respectively. CWNPs are round-shaped particles with a diameter of 70–200 nm diameter particles that when added to macrophages are taken up by membrane ruffling. CWNPs with no DHN-melanin and more glucan (pyrCWNPs) caused early macrophage activation and lowest viability, with the cells exhibiting ultrastructural modifications such as higher vacuolization and formation of autophagy-like structures. CasCWNPs promoted the highest tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) increase, also resulting in the release of partially degraded chitin, an aspect never observed in macrophage-like cells and fungi. After 6 h of interaction with CWNPs, only half were viable, except with control CWNPs. Overall, this work indicates that compounds that modify the fungal cell wall led to CWNPs with new properties that may have implications for the effects of drugs during antifungal therapy. CWNPs provide a new tool to study the interaction of hyphal fungal cell wall components with phagocytic cells and enable to show how the modification of cell wall components in
A. infectoria
can modulate the response by macrophages.

IMPORTANCE

Alternaria
species are ubiquitous environmental fungi to which the human host can continuously be exposed, through the inhalation of fungal spores but also of fragments of hyphae, from desegregated mycelia. These fungi are involved in hypersensitization and severe respiratory allergies, such as asthma, and can cause opportunistic infections in immunodepressed human host leading to severe disease. The first fungal structures to interact with the host cells are the cell wall components, and their modulation leads to differential immune responses. Here, we show that fungal cells grown with cell wall inhibitors led to cell wall nanoparticles with new properties in their interaction with macrophages. With this strategy, we overcame the limitation of
in vitro
assays interacting with filamentous fungi and showed that the absence of DNH-melanin leads to higher virulence, while caspofungin leads to cells walls that trigger higher hydrolysis of chitin and higher production of cytokines.
Early stopping versus continued retrievals after failed recanalization: associated factors and implications for outcome
Authors: Kniep Helge C , Meyer Lukas , Broocks Gabriel , Bechstein Matthias , Heitkamp Christian , Winkelmeier Laurens , Geest Vincent , Faizy Tobias D , Feyen Ludger , Brekenfeld Caspar , Flottmann Fabian , McDonough Rosalie V , Maros Mate , Schell Maximilian , Hanning Uta , Thomalla Goetz , Fiehler Jens , Gellissen Susanne
Published: September 2024

Background

Successful recanalization defined as modified Thrombolysis in Cerebral Infarction Score (mTICI) ≥2b is not achieved in 15%–20% of patients with acute ischemic stroke. This study aims to identify patient-specific factors associated with early stopping without successful recanalization. We hypothesized that the probability of the decision for early stopping during mechanical thrombectomy (MT) is higher in patients with an unfavorable prognosis.

Methods

All patients enrolled in the German Stroke Registry (GSR) between June 2015 and December 2021 were screened. Inclusion criteria were stroke in the anterior circulation and availability of relevant clinical data. For each retrieval attempt 1–3, patients with stopping and failed reperfusion (mTICI <2b) were compared with all patients with continued retrieval attempts using descriptive statistics and multivariable logistic regression.

Results

Our study included 2977 patients, 350 (12%) of which had early stopping. Higher pre-stroke Modified Rankin Scale (mRS) score (adjusted odds ratio (aOR) =1.20 (95% confidence interval (CI): 1.09; 1.32), P<0.001), higher age (aOR=1.01 (1.00; 1.02), P=0.017) and distal occlusions (aOR=1.93 (1.50; 2.47), P<0.001) as well as intraprocedural dissections/perforations (aOR=4.61 (2.95; 7.20), P<0.001) and extravasation (aOR=2.43 (1.55;3.82), P<0.001) were associated with early stopping. In patients with unsuccessful recanalization (n=622), the number of retrieval attempts (aOR=1.05 (0.94; 1.18), p=0.405) was not associated with unfavorable outcomes (90d-mRS>3).

Conclusion

The probability of early stopping was higher in patients with clinical conditions associated with: a) Favorable prognosis and assumed lower impact of recanalization success on functional status, such as distal occlusions; and b) Unfavorable prognosis, such as higher age and reduced pre-stroke functional status. Adverse events during the procedure increased the probability of early stopping. The number of recanalization attempts did not increase the risk of unfavorable outcome for patients with persistent occlusion, supporting the decision for continuation of retrieval attempts.
Spontaneous recanalization in acute large core ischemic stroke due to large vessel occlusion: a post-hoc analysis of the ANGEL-ASPECT trial
Authors: Zhang Longhui , Chen Fangguang , Nguyen Thanh N , Pan Yuesong , Liu Yufan , Wang Mengxing , Li Shuo , Sun Dapeng , Huo Xiaochuan , Jia BaiXue , Miao Zhongrong
Published: September 2024

Background

Previous studies have indicated that a subset of patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) experience spontaneous recanalization (SR), but the prognosis and factors associated with SR in these individuals are not well characterized.

Methods

We conducted a post hoc secondary analysis of the Study of Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core (ANGEL-ASPECT) trial. SR in the medical management group was defined as a modified arterial occlusive lesion (AOL) grade of 2 or 3 on computed tomography angiography (CTA) or magnetic resonance angiography (MRA) at 36 hours (±12 hours).

Results

SR was detected in 67 out of 184 patients (36.4%) in the medical management (MM) group. The median age of patients was 67 years (interquartile range (IQR) 58–72), and 48 (71.6%) were male. The adjusted odds ratio (aOR) for 90-day modified Rankin Scale (mRS) score shift toward better outcomes of the MM with SR group vs the MM without SR group was 1.83, with marginally significant difference (95% confidence interval (CI) 0.992 to 3.36; P=0.053). No significant difference was found between the MM with SR group and EVT recanalization group (aOR 1.45; 95% CI 0.86 to 2.43; P=0.16) with similar findings in the inverse probability treatment weighting analysis (OR 0.85; 95% CI 0.49 to 1.48; P=0.57). Multivariable regression analysis showed that hypertension, atherothrombotic stroke and higher clot burden score were factors associated with SR.

Conclusions

SR in medically managed patients with acute large ischemic stroke caused by LVO was associated with good functional outcome. An improved understanding of SR patients may be helpful to develop therapeutic strategy in patients with large infarct due to LVO in anterior circulation.

Trial registration number

NCT04551664.
An experimental investigation of the effect of strain rate and stress path on undrained response of nonplastic soils in direct simple shear mode
Authors: Chen Jiarui , Olson Scott M. , Banerjee Soham , Dewoolkar Mandar M. , Dubief Yves
Published: September 2024

Numerous studies have explored the influence of strain rate on the small- and large-strain shear resistance of nonplastic soils, most using conventional drained and undrained (or constant volume) laboratory tests. To supplement the initial states, soil gradations, and modes of shear examined in earlier studies, the authors used direct simple shear (DSS) tests to evaluate the effect of shear strain rate on the shear resistance of three nonplastic soils with fines contents that varied from 0% to 60%. In addition, the effect of stress path on the critical state and uniqueness of the critical state line (CSL) were explored. Results from the DSS tests on these soils indicated that irrespective of the nonplastic fines content: (i) peak undrained shear strength increased by up to approximately 9% for every order of magnitude increase in strain rate; (ii) strain rate had little to no impact on shearing resistance at the critical state regardless of stress path; and (iii) the CSL was independent of strain rate. In addition, the authors postulate that the effect of strain rate on peak undrained shear strength may be related to differences in inertia during shearing as well as particle rearrangement.
Anisotropic quark stars with an interacting quark equation of state in extra dimension
Authors: Das Krishna Pada , Bhar Piyali , Debnath Ujjal
Published: September 2024

This work revisits a modified version of the hydrostatic equilibrium equation in the presence of pressure anisotropy based on General Relativity with an extra dimension. We examine the structural features of quark stars in various dimensions by solving the Tolman–Oppenheimer–Volkoff (TOV) equation numerically using the interacting quark EoS. From our result, the compact star model with isotropic pressure can be obtained as $$\alpha $$
α
approaches zero. The energy-dependent maximum mass and its associated radius, as well as the other characteristics like pressure, energy density, stability, etc., of the quark star, are obtained using the numerical solution. Through our detailed study, we have demonstrated that the conclusions we obtained here are consistent with observable evidence in four-dimensional spacetime. In four dimensions, for different values of $$\alpha $$
α
, our obtained results can predict the mass of the compact stars PSR J0740+6620, PSR J1614-2230, Vela X-1, 4U 1608-52, 4U 1820-30, Cen X-3, and EXO 1785-248.
Probing the thermodynamics of charged Gauss Bonnet AdS black holes with the Lyapunov exponent
Authors: Lyu Xin , Tao Jun , Wang Peng
Published: September 2024

In this paper, we investigate the thermodynamic properties of the charged AdS Gauss–Bonnet black holes and their associations with the Lyapunov exponent. The chaotic features of the black holes and the isobaric heat capacity characterized by the Lyapunov exponent are studied to reveal the thermodynamic stability of the black hole phases. By considering both the timelike and null geodesics, we find that the relationship between the Lyapunov exponent and the Hawking temperature can accurately represent the features of the Small/Large phase transition and even the triple point. We also reveal the properties of the difference in the Lyapunov exponent as an order parameter. It is demonstrated that there is a negative correlation between the Lyapunov exponent and the size of the black hole shadow, which can be used to bridge the thermodynamic properties and the shadow of black holes.
A note on the Cotton flow and the Ricci flow for three-manifolds, and the Hořava–Lifshitz gravity
Authors: Cartas-Fuentevilla R. , Herrera-Aguilar A. , Calvario-Acocal J. L. A.
Published: September 2024

We consider the more general geometrical flow in the space of metrics for three-manifolds that consists of a combination of two flows, the Cotton flow and the Ricci flow; by playing a fundamental role in the detailed balance principle of the four dimensional Hořava–Lifshitz gravity, this generalized flow reveals another difficulty with this theory that attempts to be a candidate for an UV completion of Einstein general relativity, namely, the supposed emergency of the speed of light, the Newton constant, and the cosmological constant, from a deeply nonrelativistic theory of gravity. Respecting that principle, the generalized flow shows the proliferation of different limits of the theory with an unwanted behavior at both the IR and UV regimes.
DApps ecosystems: mapping the network structure of smart contract interactions
Authors: Aufiero Sabrina , Ibba Giacomo , Bartolucci Silvia , Destefanis Giuseppe , Neykova Rumyana , Ortu Marco
Published: September 2024

Decentralized applications (DApps) built on blockchain platforms such as Ethereum and coded in languages such as Solidity, have recently gained attention for their potential to disrupt traditional centralized systems. Despite their rapid adoption, limited research has been conducted to understand the underlying code structure of these applications. In particular, each DApp is composed of multiple smart contracts, each containing a number of functions that can be called to trigger a specific event, e.g., a token transfer. In this paper, we reconstruct and analyse the network of contracts and functions calls within the DApp, which is helpful to unveil vulnerabilities that can be exploited by malicious attackers. We show how decentralization is architecturally implemented, identifying common development patterns and anomalies that could influence the system’s robustness and efficiency. We find a consistent network structure characterized by modular, self-sufficient contracts and a complex web of function interactions, indicating common coding practices across the blockchain community. Critically, a small number of key functions within each DApp play a central role in maintaining network connectivity, making them potential targets for cyber attacks and highlighting the need for robust security measures.
Mathematical sense making of quantum phenomena using Dirac notation: its effect on secondary school students’ functional thinking about photons
Authors: Hennig Fabian , Tóth Kristóf , Veith Joaquin , Bitzenbauer Philipp
Published: September 2024

Previous research has consistently demonstrated that students often possess an inadequate understanding of fundamental quantum optics concepts, even after formal instruction. Findings from physics education research suggest that introducing a mathematical formalism to describe quantum optical phenomena may enhance students’ conceptual understanding of quantum optics. This paper investigates whether using formal descriptions of quantum optics phenomena – such as photon anticorrelation at a beamsplitter or single-photon interference in a Michelson interferometer – expressed in Dirac notation, can support secondary school students in developing functional thinking about photons. To investigate this, we conducted a clusterrandomized field study, comparing the improvement in functional thinking between 67 students in the intervention group, who were taught using both qualitative and quantitative reasoning, and 66 students in the control group, who were taught using only qualitative reasoning. The results indicate that mathematical formalism can indeed promote functional thinking about photons. However, the comparison between the intervention and control groups revealed that the control group exhibited a greater increase in functional thinking than the intervention group. In response to these findings, we conducted a follow-up study aimed at gaining a deeper understanding of the cognitive load associated with both approaches. Specifically, we compared the intrinsic and extraneous cognitive load of 71 students in the intervention group with those of 65 students in the control group. The data analysis revealed that the two groups had statistically significant differences in intrinsic cognitive load while the extraneous cognitive load did not difer statistically significant, indicating a higher mental effort associated to the quantitative reasoning.
Constraining of homogenized information on online spreading
Authors: Nian Fuzhong , Fu Xifei , Wang Zheming
Published: September 2024

The spread of homogenized information on social networks can create certain positive promotional effects. However, if it is excessively spread, it may lead to constraining effects and even cause negative impacts. In this paper, a spreading model called C-SIRI is proposed, which conducts an in-depth study on the constraining mechanism in the process of information spreading, as well as the rules and characteristics affecting its impact. Taking the COVID-19 epidemic information spreading on Sina Weibo social network from March 2020 to May 2022 as an example, the reliability of this model is verified. The results show that content homogeneity, participation degree and false proportion have a significant influence on the constraining mechanism of social network information spreading, and the threshold of information spreading constraining is closely related to the spreading times. This research helps to understand the role of constraining mechanism in information spreading and promote the application of social networks in information spreading prediction and control.
EFFECT OF FINTECH-ENABLED SUPPLY CHAIN FINANCE ON CORPORATE INNOVATION
Authors: YE NING , ZHOU SHAOFU , KANG YANLING
Published: September 2024

This study presents a comprehensive analysis of how the financial and technological progress of major companies affects the innovation activities of smaller businesses both upstream and downstream. The study discovered that core enterprise financial and technology development greatly improved the innovative capacity of upstream, downstream and small firms. The development of advanced financial technology in core enterprises empowers small- and medium-sized enterprises (SMEs) through a variety of beneficial effects. These effects include expanding financing options via supply chain credit, optimizing resource allocation through information sharing, promoting cooperation incentives through innovation, and effectively managing risks. These efforts collectively contribute to enhancing the innovation capacity of downstream SMEs in supply chains.
Au-decorated 2D graphitic carbon nitride (g-C3N4)-coated ZnO nanorods for improved UV photodetection application
Authors: Praween Zeya , Mayu Tai , Baro Bikash , Bayan Sayan
Published: September 2024

Two-dimensional (2D) material-based nanocomposites are fascinating for the development of ultrathin optoelectronic devices with superior efficiency. Here, we report the ultra-violet (UV) photodetection characteristics of nanocomposite made of Au-decorated 2D graphitic carbon nitride (g-C3N4)-coated ZnO nanorods. The Au nanoparticles (NPs) have been developed on g-C3N4 nanosheets using the simple chemical route, while the nanocomposite with ZnO nanorods has been obtained using a cost-effective hydrothermal method. The 2D nature has been visualized through atomic force microscopy (AFM), while the existence of Au NPs has been confirmed from the plasmonic peak in absorption spectroscopy. The coating of ZnO nanorods with the net-like sheet has been observed in field emission scanning electron microscopy (FESEM). The as-synthesized nanocomposite has been found to be efficient for UV detection due to the presence of Au NPs. The type II heterojunction formed at the g-C3N4/ZnO interface facilitates charge transfer during UV illumination, while the Au NPs help to concentrate the UV radiation by increasing the oscillator strength of the system.
ANALYSIS OF OPTIMAL PORTFOLIO ON FINITE AND SMALL-TIME HORIZONS FOR A STOCHASTIC VOLATILITY MODEL WITH MULTIPLE CORRELATED ASSETS
Authors: LIN MINGLIAN , SENGUPTA INDRANIL
Published: September 2024

In this paper, we consider the portfolio optimization problem in a financial market where the underlying stochastic volatility model is driven by n-dimensional Brownian motions. At first, we derive a Hamilton–Jacobi–Bellman equation including the correlations among the standard Brownian motions. We use an approximation method for the optimization of portfolios. With such approximation, the value function is analyzed using the first-order terms of expansion of the utility function in the powers of time to the horizon. The error of this approximation is controlled using the second-order terms of expansion of the utility function. It is also shown that the one-dimensional version of this analysis corresponds to a known result in the literature. We also generate a close-to-optimal portfolio near the time to horizon using the first-order approximation of the utility function. It is shown that the error is controlled by the square of the time to the horizon. Finally, we provide an approximation scheme to the value function for all times and generate a close-to-optimal portfolio.
Construction of Intelligent Question-Answering System to Improve Knowledge Management Service from the Perspective of Education Informatization
Authors: Han Quanzhi
Published: September 2024

With the continuous reform of education informatization, modern information technology gradually became a key technology in education. An intelligent question-answering system was constructed in this research for knowledge management services. It included an entity recognition model based on bidirectional long short-term memory attention conditional random field and a question classification model based on a bidirectional encoder using Transformers text convolutional neural network. The entity recognition model added a reverse long short-term memory propagation structure, while introducing an attention mechanism and conditional random field model. The question classification model utilized a preprocessed structure to output a feature matrix with richer semantic information, while utilizing a bidirectional encoder to extract local features of short text sentences. These experiments confirmed that the constructed model had a high precision of 0.945, which was much higher than other models. The recall of this proposed model was 0.077 higher than the control models. For precision, the proposed model had good recognition performance for methods, files and modules, with values of 0.9040, 0.9050 and 0.9160, respectively. For the recall, the question classification model had the best recognition effect on files, at 0.9060. For the [Formula: see text]1-score, the proposed model had the best recognition performance for modules, at 0.9100. The named entity recognition model constructed had high accuracy and [Formula: see text]1-score, reaching 0.931 and 0.923, indicating that it had the best classification performance in the dataset. Through intelligent question-answering systems, automatic answering of questions can be achieved, effectively improving knowledge services. This research has integrated knowledge and technology from multiple disciplines such as computer science, artificial intelligence, and natural language processing to promote the cross-integration of these disciplines in knowledge management. This interdisciplinary method not only broadens the research perspective of knowledge management but also provides new ideas and methods for the development of related fields.
The Aligning of Decarbonisation and Company Performance Goals
Authors: Melnik Alexander N. , Naoumova Irina , Ermolaev Kirill A. , Kuzmin Mikhail S.
Published: September 2024

Decarbonisation is seen as a critical factor of environmental protection policies. They include various forms of carbon emission control, carbon pricing, and the use of environmental, social, and governmental (ESG) standards and metrics. Although the urgent need for it was recognised by business communities, decarbonisation process is rather slow because of some contradiction between the interests of the company’s internal and external stakeholders. To solve this problem and achieve corporate strategic goals, we proposed a methodology based on the decoupling effect and green resource orchestration theory. In the paper, we explained the logic of aligning decarbonisation goals with company strategic objectives; described requirements and conditions for that; and confirmed that this approach can be used by companies worldwide.
Accessibility Analysis of Educational Websites Using WCAG 2.0
Authors: Singh Utkarsha , Divya Venkatesh Jeevithashree , Muraleedharan Anujith , Saluja Kamalpreet Singh , J H Anamika , Biswas Pradipta
Published: September 2024

In recent years, the internet has emerged as the primary information hub, encompassing various domains such as education, healthcare, government, and e-commerce. With a vast user base relying on websites for accessing essential information, ensuring web content accessibility has become imperative. Meeting accessibility guidelines is crucial to accommodate users with diverse abilities worldwide. This article examines accessibility variances among education board websites hosting higher-level school leaving examinations. The study evaluates the landing pages of 13 educational websites from both developing and developed countries, employing six Web Content Accessibility Guidelines (WCAG) tools endorsed by the World Wide Web Consortium (W3C). The study has meticulously compiled the outcomes of each assessment tool, delineating the diverse accessibility concerns encountered on each website. Furthermore, alternative recommendations have been proposed to assist web developers in rectifying these issues. The findings underscore a higher prevalence of accessibility issues within the education board websites of developing countries compared to their developed counterparts. Specifically, the analysis revealed prominent text contrast failures among selected web pages from developing nations, while non-text contrast failures were more prevalent in those from developed countries. Notably, the education board websites of India and Japan emerged with the highest number of accessibility issues among the sampled websites. As a way forward, a case study was shown on using LLM for making websites accessible.
(Invited) Selective Wet Etching of Semiconductor Materials by Novel Catalyst-assisted Modes
Authors: Arima Kenta , Li Junhuan , Murase Shiika , Inagaki Kouji
Published: September 2024

Since reports in the mid-1990s on metal-induced pitting on a Si surface in microelectronics, much attention has been paid to the positive use of corrosion of a semiconductor surface loaded with a metallic catalyst in solutions, known as metal-assisted chemical etching. This paper describes two novel modes of catalyst-assisted etching. The first involves the formation of nano trenches along the atomic step edges of a Si(111) surface with the help of self-assembled metallic nanowires, enabling the separation of neighboring terraces. The second discusses the science and application of nanocarbon-assisted etching, free from noble metals, of a Ge surface in water.
Modeling and Optimization of Wet ALE Process
Authors: Bassett Derek , Abel Kate
Published: September 2024

Wet ALE (atomic layer etch) processes are emerging as an important alternative to standard ALE processes in semiconductor manufacturing. Here we present a model for simulating an idealized wet ALE process that includes both chemical reactions and liquid flow in order to predict the amount of material etch, how much of the etching is true ALE vs continuous etch, and its uniformity across the wafer. This model is applied to both a simple test flow cell and flow across a spinning wafer in a typical wet single wafer process. Results show that etch amount and uniformity depends on timing of the dispense steps, flow parameters, and the kinetics of the specific chemical reactions.
Low-Temperature Selective Si:As Epitaxy
Authors: Abdula Daner , Chiu YuJen , Marozas Brendan , Khazaka Rami , Miskin Caleb K , Lee Jung Soo , Demos Alexandros T
Published: September 2024

A selective low-temperature Si:As (LT-SiAs) process is presented which utilizes cyclic deposition-etch (CDE) at <450oC. Selectivity against SiN and SiOx dielectrics and crystallinity are confirmed on gate-all-around (GAA) patterned structures. Hall measurements on blanket wafers show a resistivity minimum of 0.42 mΩ-cm at ~1.7% As for selective LT-SiAs. Secondary-ion mass spectroscopy (SIMS) profiles of P and As diffusion into intrinsic Si (i-Si) for LT-SiP/LT-SiAs/i-Si and LT-SiP/i-Si stacks show >2× benefit of using LT-SiAs spacers to minimize dopant diffusion for as-deposited, soak-annealed and spike-annealed samples. Improvement is attributed to relatively limited diffusivity of As in Si versus P and the lower As concentration needed for LT-SiAs layer to achieve minimum resistivity relative to LT-SiP (~3%). Lastly, a comparison of LT-SiAs and high-temperature Si:As (HT-SiAs) shows a ~2× reduction of As diffusion into i-Si for LT-SiAs at length scales of >10nm.
Defect-Free SiGe/Si Multistacks for Next-Generation CFET Architectures
Authors: Rengo Gianluca , Casey Daniel , Marozas Brendan , Claessens Niels , Khazaka Rami
Published: September 2024

The advancement of CMOS technology nodes demands increasingly complex device architectures. In this frame, the epitaxial deposition of complicated SiGe/Si multistacks presents a significant technology challenge required to enable such cutting-edge devices. This work presents the characterization of defect-free multistacks featuring SiGe layers with two possible Ge concentrations and incorporating either two or six stacked Si nanosheets. Our comprehensive analysis reveals good matching with the nominal structures and demonstrates remarkable repeatability of the Si channels. Furthermore, the multistacks exhibit ideal surface morphology, crucial for subsequent processing steps. Notably, the study also highlights optimal wafer-to-wafer repeatability, a key factor in ensuring consistent performance across large-scale production.
(Invited) Epitaxial Process Development and Challenges for Advanced SiGe BiCMOS
Authors: Deprat Fabien , Vives Jeremy , Gauthier Alexis , Frauenrath Marvin , Lespiaux Justine , Verdier Stephane , Ferrandon Alice , Oudot Evan , Ribot Pascal George , Chevalier Pascal
Published: September 2024

The performance of an HBT is primarily influenced by 1D dopant profile obtained by CVD epitaxy. Typically, three epitaxial layers are required to construct an HBT: the collector, the intrinsic base, and the emitter. Collector layer can be grown by either NSEG or selective epitaxy. While the NSEG process is cost effective, it results in autodoping. Switching to selective epitaxy can mitigate autodoping but must be controlled to minimize faceting. The intrinsic base is critical to device performance, with boron positioning being a key factor. Incorporating substitutional carbon atoms into the SiGe lattice significantly reduces boron diffusion. By switching from SiH4 to Si2H6, three times more substitutional carbon incorporation in SiGe without interstitial C atoms at 550 °C is achieved. Below 600 °C, the co-flow approach is ineffective, necessitating a cyclic deposition-etch (CDE) approach to maintain selectivity. Comparisons between CDE and single deposition-etch (DE) approaches show that CDE degrades the monocrystalline SiGeC:B layer, resulting in high RMS roughness and degraded morphology. In contrast, the DE approach shows promising results with lower RMS roughness and no significant morphological degradation. The last epitaxial layer discussed is the emitter. Current fabrication methods involve non-selective Si:As deposition at growth temperatures above 600 °C, resulting in polycrystalline Si:As deposition on dielectrics and monocrystalline Si:As growth on silicon. A novel process developed at 550 °C using Si2H6 as silicon precursor yields monocrystalline emitter by amorphous deposition on dielectrics followed by solid phase epitaxial regrowth. However, this process exhibits TED of arsenic, making it currently not viable.
Developing the Metrology for Atomic Level Spatial Distribution and Local Chemistry Analysis of in-Situ Dopants By Atom Probe Tomography
Authors: Lin Jhao-Rong , Morris Richard J. H. , Scheerder Jeroen E. , Hikavyy Andriy Yakovitch , Porret Clement , Vantomme André , Fleischmann Claudia
Published: September 2024

We present a metrology for analyzing the spatial distribution and local chemistry of in-situ dopants using Atom Probe Tomography (APT). Our approach integrates a 'local composition method' with a Kolmogorov-Smirnov test on a 3D APT dataset to evaluate spatial inhomogeneity. This methodology was applied to a nanometer scale in-situ highly boron-doped silicon germanium layer. By subdividing the dopant-dopant local composition distribution into three, its influence on the localized chemical environment was determined. Our findings reveal an inhomogeneous spatial distribution for the dopant and the Si/Ge atoms. Our results demonstrate the potential for linking at an atomic-scale the epitaxial growth conditions of dopants and the matrix elements to a device performance.