bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrochemistry at additively manufactured electrodes
Authors: Siqueira Gilvana P. , de Faria Lucas V. , Muñoz Rodrigo A. A.
Published: July 2023

This chapter presents a brief guide for those who are interested in the use of additively manufactured (3D printed) electrodes for electroanalysis. We focus on the electrochemistry of electrodes fabricated by the fused deposition modeling (FDM) printing technique using polymeric filaments based on polylactic acid (PLA) containing carbon conductive particles (e.g., graphene, graphite or carbon black). Electrode surface treatment, sources of conductive filaments (commercial and lab-made filaments) and 3D printing parameters aiming at improved electrochemical activity are discussed herein. We show the voltammetric results obtained with common redox probes to investigate the electrochemical activity of such 3D printed electrodes, before and after surface treatment, to illustrate the expected voltammetric data to the readers.
First-principles evaluation of dopant impact on structural deformability and processability of Li7La3Zr2O12
Authors: Dive A. , Kim K. , Kang S. , Wan L. F. , Wood B. C.
Published: July 2023

Li7La3Zr2O12 (LLZO) and related ceramic solid electrolytes feature excellent stability and reasonable ionic conductivity, but processing remains challenging.
Ultrafast sensitivity-controlled and specific detection of extracellular vesicles using optical force with antibody-modified microparticles in a microflow system
Authors: Fujiwara Kana , Takagi Yumiko , Tamura Mamoru , Omura Mika , Morimoto Kenta , Nakase Ikuhiko , Tokonami Shiho , Iida Takuya
Published: July 2023

We propose a detection method of 103–104 nanoscale extracellular vesicles secreted from cancer cells and distinguish their multiple membrane proteins using controlled optical force and microfluidic pressure only by 5 minutes laser irradiation.
Fluorescence detection of 4-nitrophenol and α-glucosidase activity based on 4-nitrophenol-regulated fluorescence of silicon nanoparticles
Authors: Liu Fangning , Liang Fan , Li Zhe , Kang Ge , Wang Tingting , Chen Chuanxia , Lu Yizhong
Published: July 2023

Fluorescence detection of 4-nitrophenol, α-glucosidase activity and α-glucosidase inhibitors based on the inner filter effect on Si nanoparticles synthesized through a green method.
Metabolite profiling from different parts of tender fruit endosperm of Borassus flabellifer L. (ice apple)
Authors: Vasudevan Vinduja , Prabaharan Janani , Krishnan Nagasathiya , K Abinaya , Gopinath Subash C. B. , Raman Pachaiappan
Published: July 2023

Borassus flabellifer L., commonly known as Asian palmyra, is native to South and Southeast Asia.
Reductive cleavage of annulated 5,6-dihydro-2H-1,2,4-thiadiazine-1,1-dioxides: medium sized ring azasultams
Authors: Lysenko Viacheslav , Nazarenko Kostiantyn , Shishkina Svitlana , Kostyuk Aleksandr
Published: July 2023

A novel method for synthesis of medium sized ring azasultams was proposed.
Correction: Making good on a promise: ionic liquids with genuinely high degrees of thermal stability
Authors: Rabideau Brooks D. , West Kevin N. , Davis James H.
Published: July 2023

Correction for ‘Making good on a promise: ionic liquids with genuinely high degrees of thermal stability’ by Brooks D. Rabideau et al., Chem. Commun., 2018, 54, 5019–5031, https://doi.org/10.1039/C8CC01716F.
An ab initio study of the photodissociation of CH2I and CH2I+
Authors: Bouallagui A. , Zanchet A. , Bañares L. , García-Vela A.
Published: July 2023

The photodissociation pathways of the CH2I and CH2I+ species are investigated by means of high-level ab initio calculations.
Substitution (CH3, Cl, or Br) effects of the imidazolate linker on benzene adsorption kinetics for the zeolitic imidazolate framework (ZIF)-8
Authors: Yagi Ryohei , Ueda Takahiro
Published: July 2023

Substitution effects of the imidazolate linker affects significantly benzene adsorption kinetics. In particular, methyl groups play an important role in the energetic advantage when the benzene molecule passes through the 6-membered ring aperture.
Rationally heteroarylated pyridines as hole transport materials for OLEDs
Authors: Kumar Krishan , Karmakar Anirban , Chen Feng-Rong , Jou Jwo-Huei , Ghosh Subrata , Banik Subrata , Kumar Sunil
Published: July 2023

Donor–acceptor-based hole transport materials (HTMs) built on a pyridine-core are demonstrated. Single crystal analysis and theoretical simulations have been performed to assess the potential of the developed materials.
An automated quantum chemistry-driven, experimental characterization for high PCE donor–π–acceptor NIR molecular dyes
Authors: Santaloci Taylor J. , Meador William E. , Wallace Austin M. , Valencia E. Michael , Rogers Blake N. , Delcamp Jared H. , Fortenberry Ryan C.
Published: July 2023

A readily accessible dye molecule with potential properties well-beyond the state-of-the-art for dye-sensitized solar cells is realized from extensive quantum chemical characterization of nearly 8000 stochastically-derived novel molecules.
Developmental toxicity of the emerging contaminant cyclophosphamide and the integrated biomarker response (IBRv2) in zebrafish
Authors: Hema Tamilselvan , Poopal Rama-Krishnan , Ramesh Mathan , Ren Zongming , Li Bin
Published: July 2023

The safety of cyclophosphamide (CP) in the early developmental stages is not studied yet; it is important to study the responses at these stages because it might have relevance to CP-administered humans.
Synthesis of thermoresponsive PNIPAm-b-PVP-b-PNIPAm hydrogels via aqueous RAFT polymerization
Authors: Ball Lauren E. , Garbonova Gabriela , Pfukwa Rueben , Klumperman Bert
Published: July 2023

A stimuli-responsive BAB triblock copolymer of PNIPAm-b-PVP-b-PNIPAm, which displayed a thermoreversible sol–gel transition, was readily synthesized via redox-initiated aqueous RAFT mediated polymerization, under mild conditions.
Fragment expansion with NUDELs – poised DNA-encoded libraries
Authors: Salvini Catherine L. A. , Darlot Benoit , Davison Jack , Martin Mathew P. , Tudhope Susan J. , Turberville Shannon , Kawamura Akane , Noble Martin E. M. , Wedge Stephen R. , Crawford James J. , Waring Michael J.
Published: July 2023

Fragment growing using poised DNA-encoded libraries, which allow the coupling of a targeted active fragment, allows the optimisation of fragment hits to potent compounds in a single operation, illustrated by the discovery of a 51 nM BRD4 ligand.
HAA by the first {Mn(iii)OH} complex with all O-donor ligands
Authors: Moore Shawn M. , Sun Chen , Steele Jennifer L. , Laaker Ellen M. , Rheingold Arnold L. , Doerrer Linda H.
Published: July 2023

We have synthesized the first {Mn(iii)OH} complex in an all O-donor environment K2[Mn(OH)(pinF)2], 3, formed by deprotonation of the corresponding {Mn(iii)OH2} complex, K[Mn(OH2)(pinF)2], 1. Complex 3 oxidizes substrates with weak N–H and O–H bonds.
A Lyapunov spectrum based hybrid static and dynamic approach for contingency ranking
Authors: Aghtar Mahdi , Cheraghzadeh Mohammadreza , Doroudi Aref , Nasrabadi Ali Motie
Published: July 2023

The goal of contingency ranking is to provide a list of possible critical situations and rank them according to the severity of their impact on a power network. The methods of contingency ranking may be divided into two major categories: static and dynamic techniques. Static approaches are fast and can be implemented in real‐time, but they present different results depending on the parameter which has been selected for contingency ranking. Dynamic methodologies are more accurate than static ones, but they are time‐consuming. This paper presents a novel combined static and dynamic method for contingency ranking which takes advantage of both techniques and shows the performance evaluation for the hybrid method using accuracy and efficiency as criteria. The proposed method uses three well‐known static indices and the Lyapunov spectrum based dynamic approach to select the worst critical lines. IEEE 39‐bus (New England grid) and IEEE 118‐bus networks are utilized to verify the proposed method. The method provides speed and accuracy. One of the prominent features of the proposed approach is its ability to rank contingencies that lead to network load flow divergence.
Hygrothermal ageing performance of high temperature vulcanised silicone rubber and its degradation mechanism
Authors: Deng Yu , Peng Bo , Liu Zheyuan , Du Yujun , Zhou Songsong , Liu Jinghua , Yu Xinzhe , Zhou Jun
Published: July 2023

High temperature vulcanised silicone rubber (SR) has excellent hydrophobicity and thus is widely applied both in indoor and outdoor insulation. According to the analysis of different experimental ageing tests and field investigation of SR, temperature and humidity are considered to be the fundamental factors during degradation. Hygrothermal ageing was proposed in this study to simulate the chalking state of the SR, finally leading to the irreversible degradation far below the thermal decomposition temperature. The variation of morphology, hardness and polydimethylsiloxane (PDMS) content was quantified during the yearlong hygrothermal ageing test. It is implied that the gradual process of whitening and hardening are accompanied by the decline of the PDMS content. Finally, ageing delamination in SR and its degradation mechanism were proposed.
FCUnet: Refined remote sensing image segmentation method based on a fuzzy deep learning conditional random field network
Authors: Ma Xiangyue , Xu Jindong , Chong Qiangpeng , Ou Shifeng , Xing Haihua , Ni Mengying
Published: July 2023

Image segmentation is pivotal for the understanding of high‐resolution remote sensing images (HRRS). However, because of the inherent uncertainties in remote sensing images and the highly complex resolution of HRRS, ambiguity often occurs among some geographic entities in the segmentation process, and the fine segmentation of HRRS is not considered sufficiently for most existing segmentation methods. Therefore, in this paper, the authors propose a new collaborative neural network structure called fuzzy deep learning conditional random field network (FCUnet) to solve the refined segmentation of HRRS. First, the authors design a fuzzy U‐Net classification network to obtain effective feature information, which introduces the fuzzy logic unit into the network to process the ambiguity and uncertainty of HRRS. Then, the authors introduce the conditional random field (CRF) at the end of FCUnet to optimize the image segmentation results. Finally, the authors validated the effectiveness and superiority of their approach on three data sets. The experiment results revealed that FCUnet had better refined segmentation performance and generalization ability than state‐of‐the‐art methods.
Neural surface reconstruction with saliency‐guided sampling in multi‐view
Authors: Li Xiuxiu , Guo Yongchen , Jin Haiyan , Zheng Jiangbin
Published: July 2023

In this work, a neural surface reconstruction framework is presented. In order to perform neural surface reconstruction using 2D supervision, a weighted random sampling based on saliency is introduced for training the deep neural network. In the proposed method, self‐attention is used to detect the saliency of input 2D images. The saliency map, that is, the weight matrix of the weighted random sampling, is used to sample the training samples. As a result, more samples in the reconstructed object area are collected. Moreover, an update strategy for weight based on sampling frequency is adopted to avoid the points that cannot be sampled all the time. The experiments are implemented in real‐world 2D images of objects with different material properties and lighting conditions based on the DTU dataset. The results show that the proposed method produces more detailed 3D surfaces, and the rendered results are closer to the raw images visually. In addition, the mean of peak signal‐to‐noise ratio (PNSR) is also improved.
Adaptation of an asexual population with environmental changes
Authors: Lavigne Florian
Published: July 2023

Because of mutations and selection, pathogens can manage to resist to drugs. However, the evolution of an asexual population (e.g., viruses, bacteria and cancer cells) depends on some external factors (e.g., antibiotic concentrations), and so understanding the impact of the environmental changes is an important issue.

This paper is devoted to model this problem with a nonlocal diffusion PDE, describing the dynamics of such a phenotypically structured population, in a changing environment. The large-time behaviour of this model, with particular forms of environmental changes (linear or periodically fluctuations), has been previously developed. A new mathematical approach (limited to isotropic mutations) has been developed recently for this problem, considering a very general form of environmental variations, and giving an analytic description of the full trajectories of adaptation.

However, recent studies have shown that an anisotropic mutation kernel can change the evolutionary dynamics of the population: some evolutive plateaus can appear. Thus the aim of this paper is to mix the two previous studies, with an anisotropic mutation kernel, and a changing environment. The main idea is to study a multivariate distribution of (2n) “fitness components”. Its generating function solves a transport equation, and describes the distribution of fitness at any time.
Velopalatinales Coupling in der medikamentös induzierten Schlafendoskopie: Analyse der Kollapsmuster
Authors: Hänsel Toni , Olze Heidi , Arens Philipp
Published: July 2023

Hintergrund Die medikamentös induzierte Schlafendoskopie (MISE) ist ein etabliertes diagnostisches Verfahren zur Beurteilung des oberen Atemwegs bei Patienten mit obstruktiver Schlafapnoe (OSA). Ein anatomisch-physiologischer Mechanismus zur Öffnung der oberen Atemwege ist das velopalatinale Coupling (VC). In der MISE wird die Atemwegsöffnung u.a. durch Unterkiefervorschub mittels modifizierten Esmarch-Handgriffs (mEH) simuliert.

Material und Methoden Es wurden retrospektiv alle nach VOTE-Schema befundeten MISE der letzten 15 Monate eingeschlossen. Häufigkeit und Art des Kollapses auf den anatomischen Ebenen wurden erfasst. Apnoe-Hypopnoe-Index (AHI), Body-Mass-Index (BMI) und Epworth Sleepiness Scale (ESS) wurden ermittelt. Der Effekt des mEH auf die anatomischen Ebenen wurde ausgewertet.

Ergebnisse Es konnten 61 Patienten eingeschlossen werden (f=13, m=48, 54,3±12,9 J, ESS 11±5,5, AHI 30,2±19/h, BMI 29,7±4,5kg/m2). Zwischen AHI und BMI konnte eine signifikante Korrelation von r=0,30 (p=0,02) ermittelt werden. Auf Velumebene wurde bei 16,4% ein konzentrischer, bei 70,5% ein anterior-posteriorer (a.p.) und bei 11,5% ein lateraler Kollaps festgestellt. Bei 75,5% der Patienten wurde mittels mEH eine Auflösung des Kollapses beobachtet. Bei Vorliegen eines konzentrischen Kollapses zeigte sich eine Öffnung in 33,3% der Fälle im Vergleich zu 86,5% bei a.p. Kollaps (p=0,003). Ein Zungengrundkollaps wurde in 98,0% der Fälle aufgelöst.

Schlussfolgerungen Es konnte ein Zusammenhang zwischen dem Erfolg des mEH auf die Atemwegsöffnung auf Velumebene und dem Muster des Gaumenkollapses gezeigt werden. Insbesondere bei Hypoglossusstimulation und progenierenden Therapieverfahren scheint ein funktionierendes VC relevant zu sein, sodass der Optimierung der präoperativen Diagnostik eine besondere Bedeutung zukommt.
Revisiting the World’s Strictest COVID-19 Lockdown:
Formidable Mental Health Challenges
Authors: Guan Beier , Li Ruihua , Huang Chuanning , Du Jiang , Zhao Min , Liu Shuyan
Published: July 2023

Introduction Many nations have implemented lockdowns to prevent and
minimize the spread of infections in healthcare settings. However, the impact of
lockdown duration on mental health remains controversial.

Methods We conducted a retrospective study using online questionnaires to
assess the mental health status of the general population during the Shanghai
lockdown period from March to May 2022. The mental health of the participants
was evaluated by the 12-item General Health Questionnaire (GHQ-12), in which a
cut-off score of 12 or more indicated psychological distress. A logistic
regression model was used to evaluate the relationship between lockdown duration
and mental health.

Results Among 2139 participants (mean age: 26.12 years, standard
deviation: 6.37, 731 females; 1378 unmarried; 1099 Shanghai residents),
approximately 47% reported psychological distress (GHQ-12≥12).
Participants exposed to lockdown reported significantly higher GHQ-12 scores
(11.93±6.81 vs. 8.73±6.35, p<0.001). In our
logistic regression model, participants who experienced the longest lockdown
(43–61 days) had a significantly higher risk of psychological distress
compared with those who did not (odds ratio: 3.10, 95% confidence
interval: 2.06–4.70, p<0.001).

Discussion Lockdown duration significantly affects mental health, with
longer lockdown duration being associated with worse mental health status. The
relationship between lockdown and mental health should not be neglected in case
of lockdown in response to future pandemics.
The Report of Community-Based and Government-Endorsed Screening Program of Atrial Fibrillation in Taiwan
Authors: Chao Tze-Fan , Yeh Yung-Hsin , Chan Yi-Hsin , Lin Fang-Ju , Chen Tien-Hsing , Pan Kuo-Li , Lin Jiunn-Cherng , Lin Yenn-Jiang , Chen Shih-Ann
Published: July 2023

Background Although international guidelines recommended opportunistic screening for atrial fibrillation (AF), the community-based AF screening program incorporated into the government-endorsed health care system is rarely reported in Asian countries.

Objectives We aimed to test the feasibility of adding AF screening into the preexistent adult health check program and report the AF detection rate and percentages of OAC prescriptions before and after AF screening with the involvement of public health care systems.

Methods We performed this program in three counties (Chiayi county, Keelung City, and Yilan county) in Taiwan which have their own official preexistent adult health check programs conducted by public health bureaus for years. However, electrocardiography (ECG) was not included in these programs before. We cooperated with the public health bureaus of the three counties and performed single-lead 30-second ECG recording for every participant.

Results From January to December 2020, AF screening was performed in 199 sessions with 23,572 participants. AF was detected in 278 subjects with a detection rate of 1.19% (age ≥65 years: 2.39%; ≥75 years: 3.73%). The mean CHA2DS2-VASc score of these 278 subjects was 2.36, with 91% of them had a score ≥1 (males) or ≥2 (females). The number needed to screen was 42 and 27 for subjects aged ≥65 and ≥75 years, respectively. The prescription rate of OACs significantly increased from 11.4 to 60.6% in Chiayi county and from 15.8 to 50.0% in Keelung City after screening (both p-values <0.001).

Conclusion This community-based and government-endorsed AF screening project in Taiwan demonstrated that incorporation of AF screening into the preexistent adult health check programs through co-operations with the government was feasible. Actions to detect AF, good education, and well-organized transferring plan after AF being detected with the involvement of public health care systems could result in a substantial increase in the prescription rate of OACs.
General-purpose measurement interface for physics experiments
Authors: Spencer C. D. , Seligmann P. , Briotta D. A.
Published: July 2023

Characteristics and capabilities of a measurement interface are proposed. The primary goal is that the interface be able to do virtually all instructional physics experiments while maintaining portability to a variety of host computers and while giving users the ability to develop their own applications. Three specific approaches to implementing the interface are outlined.
A template for writing programs
Authors: Carlson Edward H.
Published: July 2023

Templates for writing programs in BASIC, FORTRAN, and Pascal are introduced and that for BASICA is described in full as an example. Reasons for using a template in program writing by students, instructors, and researchers are discussed and include increasing productivity, clarity, and communication between persons in an organization.
Data smoothing routine
Authors: Hayden Howard C.
Published: July 2023

A noise removal program is available to interested users for use on IBM and compatible personal computers. The routine removes noise that is incompatible with the “instrument function,” which characterizes the apparatus used in obtaining the data.
Coexistence of superconductivity and charge-density waves: evidence from tunneling studies (Review article)
Authors: Gabovich Alexander M. , Voitenko Alexander I. , Ekino Toshikazu , Sugimoto Akira , Yoshida Daiki , Saito Takeshi , Li Mai Suan , Szymczak Henryk
Published: July 2023

The review summarizes certain theoretical and experimental studies of the quasiparticle, J, and Josephson, IJ, currents between superconductors partially dielectrized with charge-density waves (CDWs). A relation between the Cooper and electron-hole pairings and their manifestations in high-Tc oxides have been analyzed. It was shown that the CDW fingerprints can be found in a lot of already observed dependences. All described results are considered in the framework of the historical context.
Electronic density of state in valence fluctuating kondo lattice systems studied by point-contact spectroscopy (Review article)
Authors: Shiga Masanobu , Maruyama Isao , Mitsuda Akihiro , Wada Hirofumi , Kawae Tatsuya
Published: July 2023

This article reviews our recent point-contact spectroscopy (PCS) investigation in valence fluctuating Kondo lattice systems, EuNi2P2 and Ge-substituted EuNi2(P0.8Ge0.2)2, and YbPd. A heavy fermion (HF) compound EuNi2P2 exhibits a significant valence fluctuation owing to the intermediate Eu valence of 2.5 + at low temperatures, leading to a strong hybridization between the conduction and f electrons (c–f hybridization). The electronic density of state measurements on EuNi2P2 by using PCS technique reveal that the HF behavior arises from the formation of the indirect hybridization gap with a double-peak structure near the Fermi level due to c–f hybridization. In EuNi2(P0.8Ge0.2)2, the valence fluctuation is suppressed by the Ge substitution, and the separation of the double-peak structure decreases. These suggest that the HF behavior is induced by the valence fluctuation. In YbPd, where two-dimensional (2D) layers of Yb3+ and Yb2.6+ are alternately aligned, a HF-like behavior with a large Sommerfeld coefficient appears at low temperatures in the specific heat. The PCS spectra represent a zero-bias dip structure with an asymmetric background, reproduced by the summation of two Fano curves with two different characteristic temperatures, meaning the formation of two Kondo resonance states for each Yb3+ and Yb2.6+ site. These suggest that a local coherence causes the large Sommerfeld coefficient in the 2D layers of Yb3+, which are screened by the conduction electrons provided by the valence fluctuating Yb2.6+ sites. The observed results indicate that PCS is a powerful technique for examining the variation of electronic DOS in valence fluctuating Kondo lattice systems.
A model for critical current effects in point-contact Andreev-reflection spectroscopy
Authors: Daghero Dario , Piatti Erik , Zhigadlo Nikolai D. , Gonnelli Renato S.
Published: July 2023

It is well known that point-contact Andreev-reflection spectroscopy provides reliable measurements of the energy gap(s) in a superconductor when the contact is in the ballistic or diffusive regime. However, especially when the mean free path of the material under study is small, obtaining ballistic contacts can be a major challenge. One of the signatures of a Maxwell contribution to the contact resistance R is the presence of “dips” in the differential conductance, associated with the sudden appearance of a Maxwell term, in turn, due to the attainment of the critical current of the material in the contact region. Here we show that using a proper model for the R(I) of the material under study, it is possible to fit the experimental curves (without the need of normalization) obtaining the correct values of the gap amplitudes even in the presence of such dips, as well as the temperature dependence of the critical current in the contact. We present a test of the procedure in the case of Andreev-reflection spectra in Mg0.85Al0.15B2 single crystals.
Evidence for ferroelastic switching and nanoscopic domains in polycrystalline Si-doped hafnium oxide films
Authors: Lederer M. , Mart C. , Kämpfe T. , Lehninger D. , Seidel K. , Czernohorsky M. , Weinreich W. , Volkmann B. , Eng L. M.
Published: July 2023

The mechanism of nanoscopic domain switching in ferroelectric hafnium oxide and its implications for antiferroelectric-like behavior as well as for the wake-up effect is still widely discussed. Understanding this mechanism is of vital importance for a multitude of applications like piezoelectric actuators, pyroelectric sensors, and nonvolatile memory devices. In this article, electrical and physical analysis methods are used to characterize ferroelectric hafnium oxide on the nanoscopic as well as the macroscopic length scale. Evidence for nanoscopic domains is found using transmission Kikuchi diffraction. In combination with macroscopic Preisach density measurements, strong evidence is found that antiferroelectric-like behavior and wake-up are governed by ferroelastic switching, i.e., a 90° domain wall motion. Based on these insights, the material stack can be optimized to further improve microelectronic applications based on HfO2.
A confocal laser-induced fluorescence diagnostic with an annular laser beam
Authors: Romadanov I. , Raitses Y.
Published: July 2023

In this work, we report an annular beam confocal laser-induced fluorescence (LIF) configuration, which allows for high spatial resolution measurements of plasma properties in plasma setups and sources with limited optical access. The proposed LIF configuration utilizes the annular laser beam generated by a pair of diffractive axicons. The LIF signal is collected along the main optical axis within the ring region. It is shown experimentally that at a focal distance of 300 mm, a spatial resolution of ∼5.3 mm can be achieved. Using geometric optics estimations, we showed that ∼1 mm resolution at the same focal distance could potentially be achieved by modifying laser beam parameters. This approaches the localization accuracy of conventional LIF collection methods (with crossing laser beam injection and fluorescence collection optical paths). Measurements of the ion velocity distribution function in an argon plasma using both the confocal LIF with an annular laser beam and conventional LIF demonstrate a satisfactory agreement. The proposed LIF setup has potential applications for diagnostics in various plasma processing equipment and plasma sources, such as hollow cathodes, microplasmas, electric propulsion, etc.
Potassium-doped nano graphene as an intermediate layer for graphene electronics
Authors: Yamada Takatoshi , Masuzawa Tomoaki , Okigawa Yuki
Published: July 2023

To suppress the intrinsic carrier density and increase the carrier mobility in graphene on a silicon dioxide (SiO2) substrate, potassium (K)-doped nano graphene was introduced as an intermediate layer between the graphene layer and SiO2 substrate. Back-gate type graphene field effect transistors with four terminal structures were fabricated, and their electrical properties were measured under vacuum. The results showed that the Dirac point shifted from +9.0 to −0.2 V after inserting the K-doped nano graphene. The results suggested that inserting the intermediate layer compensated for the intrinsic holes and achieved an electron doping of 2 × 1012 cm−2. The field-effect mobilities of electrons and holes also increased because the ionized K-atoms in the intermediate layer shielded the electric force from the negatively charged impurities in SiO2. The K density was estimated using x-ray photoelectron spectroscopy to be 1.49 × 1013 cm−2, and the C1s peak shifted by 0.2 eV, which confirms the upward modulation of the graphene Fermi level by the K-doped nano graphene intermediate layer. These results demonstrated the advantages of the intermediate layer on the carrier density and mobility in graphene.
Effects of surge and roll motion on a floating tidal turbine using the actuator-line method
Authors: Fernandez-Rodriguez Emmanuel
Published: July 2023

This paper employs a dynamic and sliding mesh in the simulation of both uncoupled and coupled surge and roll motions of a tidal stream turbine, utilizing a modified actuator-line method. The modification involves the relocation of blade elements in relation to the grid. Detailed analyses are conducted on the Cp and Cz variations in surge, roll, and coupled motions at various frequencies and amplitudes. It is observed that changing the amplitude and frequency of surge and roll motions both impacts the amplitude of Cp and Cz. Interestingly, the Cp and Cz variations in surge motion are inversely proportional to velocity variations, while they are directly proportional in roll motion. The influence of the surge motion on Cp Cz plays a major role, while the addition of the roll motion increases the mean values of Cp and Cz. Due to the combination of the wake characteristics of both surge and roll, the coupled motion wake exhibits a contraction–expansion oscillation pattern. In a coupled motion with equal periods, the ring and strip tail vortex characteristics of both motions are apparent. A surge period increment diminishes the surge's tail vortex characteristic, whereas an increase in the roll period gradually erodes the roll's tail vortex characteristic. The coefficient variation of the tangential and normal forces (cn, ct) in combined motion mirror that of surge motion, presenting a convex table per surge cycle with depressions at the 1/2T and 1T points. The peak of cn and ct in surge motion are approximately 0.28 and 0.03, respectively, while in roll motion, they are around 0.261 and 0.025. The exploration of cyclic stress impacts on the turbine, and the potential instability on the platform could be valuable directions for future research.
Flow reconstruction from sparse sensors based on reduced-order autoencoder state estimation
Authors: Tan Andy C. C.
Published: July 2023

The reconstruction of accurate and robust unsteady flow fields from sparse and noisy data in real-life engineering tasks is challenging, particularly when sensors are randomly placed. To address this challenge, a novel Autoencoder State Estimation (AE-SE) framework is introduced in this paper. The framework integrates sensor measurements into a machine learning-based reduced-order model (ROM) by leveraging the low-dimensional representation of flow fields. The proposed approach is tested on two direct numerical simulation benchmark examples, namely, circular and square cylinders and wake flow fields at Re = 100. The results demonstrate satisfactory performance in terms of accuracy and reconstruction efficiency. It achieves the same accuracy as traditional methods while improving reconstruction efficiency by 70%. Moreover, it preserves essential physical properties and flow characteristics even in the noisy data, indicating its practical applicability and robustness. Experimental data validation confirms a relative error below 5% even at a noise level of 12%. The flexibility of the model is further evaluated by testing it with a trained ROM under varying Reynolds numbers and benchmark cases, demonstrating its ability to accurately estimate and recognize previously unseen flow fields with appropriate training datasets. Overall, the proposed AE-SE flow reconstruction method efficiently and flexibly leverages ROM for the low-dimensional representation of complex flow fields from sparse measurements. This approach contributes significantly to the development of downstream applications such as design optimization and optimal control.
Wall effect on cluster particle's settling terminal velocity and drag coefficient in Newtonian and non-Newtonian fluid medium
Authors: Mohammad Hussain , Munshi Basudeb
Published: July 2023

The experimental investigation of the wall effect on the cluster particle settling in the Newtonian and non-Newtonian fluid medium is carried out in three different diameter flow channels. The cluster usually forms during the sedimentation of particles in a fluid medium, so it becomes necessary to study the behavior of the cluster particles. Different cluster particles are considered depending on the number of spheres (N) attached to the cluster and the cluster's shape. The present experiment covers the following range of conditions: 0.05 ≤ deq/D ≤ 0.24, 2 ≤ N ≤ 7, 0.64 ≤ n ≤ 1, and 0.14 ≤ K ≤ 1.81. The results reveal that the terminal velocity varies with the blockage ratio (deq/D), N, and cluster shape. For a particular deq/D ratio and the same N, the terminal velocity of polyhedron particles is high compared to the planar and chain shape particles. The blockage ratio and the Reynolds number affect the wall factor of the cluster particles. However, from the experiment, it is observed that the wall effect also depends on the orientation of the particles. The impact of the wall on the cluster particle is high in Newtonian fluid when compared to cluster particles in non-Newtonian fluid. The present work additionally investigates the influence of drag on cluster particles in the presence and absence of the wall effect. The numerical relationships are developed to predict experimental results in Newtonian and non-Newtonian fluid mediums.
Two-phase flow simulations of surface waves in wind-forced conditions
Authors: Loft Malte , Kühl Niklas , Buckley Marc P. , Carpenter Jeffrey R. , Hinze Michael , Veron Fabrice , Rung Thomas
Published: July 2023

The paper is devoted to two-phase flow simulations and investigates the ability of a diffusive interface Cahn–Hilliard volume-of-fluid model to capture the dynamics of the air–sea interface at geophysically relevant Reynolds numbers. It employs a hybrid filtered/averaging improved detached eddy simulation method to model turbulence and utilizes a continuum model to account for surface tension if the diffuse interface is under-resolved by the grid. A numerical wind-wave tank is introduced, and results obtained for two known wind-wave conditions are analyzed in comparison to experimental data at matched Reynolds numbers. The focus of the comparison is on both time-averaged and wave-coherent quantities, and includes pressure, velocity as well as modeled and resolved Reynolds stresses. In general, numerical predictions agree well with the experimental measurements and reproduce many wave-dependent flow features. Reynolds stresses near the water surface are found to be especially important in modulating the critical layer height. It is concluded that the diffusive interface approach proves to be a promising method for future studies of air–sea interface dynamics in geophysically relevant flows.
The Atg1 complex, Atg9, and Vac8 recruit PI3K complex I to the pre-autophagosomal structure
Authors: Hitomi Kanae , Kotani Tetsuya , Noda Nobuo N. , Kimura Yayoi , Nakatogawa Hitoshi
Published: July 2023

In macroautophagy, cellular components are sequestered within autophagosomes and transported to lysosomes/vacuoles for degradation. Although phosphatidylinositol 3-kinase complex I (PI3KCI) plays a pivotal role in the regulation of autophagosome biogenesis, little is known about how this complex localizes to the pre-autophagosomal structure (PAS). In Saccharomyces cerevisiae, PI3KCI is composed of PI3K Vps34 and conserved subunits Vps15, Vps30, Atg14, and Atg38. In this study, we discover that PI3KCI interacts with the vacuolar membrane anchor Vac8, the PAS scaffold Atg1 complex, and the pre-autophagosomal vesicle component Atg9 via the Atg14 C-terminal region, the Atg38 C-terminal region, and the Vps30 BARA domain, respectively. While the Atg14–Vac8 interaction is constitutive, the Atg38–Atg1 complex interaction and the Vps30–Atg9 interaction are enhanced upon macroautophagy induction depending on Atg1 kinase activity. These interactions cooperate to target PI3KCI to the PAS. These findings provide a molecular basis for PAS targeting of PI3KCI during autophagosome biogenesis.
Investigation of the relationship between mirror proton radii and neutron-skin thickness*
Authors: Ding Meng-Qi , Su Ping , Fang De-Qing , Wang Si-Min
Published: July 2023

Through systematic investigations using the axially deformed solutions of the Skyrme-Hartree-Fock-Bogoliubov equations with 132 sets of Skyrme interaction parameters, it is confirmed that the neutron-skin thickness (

) of a neutron-rich nucleus is proportional to the difference between the proton radii of mirror nuclei (

). This indicates that

may be deduced from

. Compared with the results of the Skyrme-Hartree-Fock model, pairing effects are found to enhance the correlation for most mirror pairs, whereas deformation effects may weaken the correlation. Furthermore, the correlation between

and

is studied for isotones with

and

, which reveals a stronger linear correlation with increasing

. This result demonstrates that it is possible to extract the neutron-skin thickness of an unstable nucleus from the proton radii difference of the mirror nuclei of its isotones.
Predicting particle deposition using a simplified 8-path in silico human lung prototype
Authors: Barrio-Perotti R , Martín-Fernández N , Vigil-Díaz C , Walters K , Fernández-Tena A
Published: July 2023

Understanding particle deposition in the human lung is crucial for the assessment of environmental pollutants and the design of new drug delivery systems. Traditionally, research has been carried out by experimental analysis, but this generally requires expensive equipment and exposure of volunteers to radiation, resulting in limited data. To overcome these drawbacks, there is an emphasis on the development of numerical models capable of accurate predictive analysis. The most advanced of these computer simulations are based on three-dimensional computational fluid dynamics. Solving the flow equations in a complete, fully resolved lung airway model is currently not feasible due to the computational resources required. In the present work, a simplified lung model is presented and validated for accurate prediction of particle deposition. Simulations are performed for an 8-path approximation to a full lung airway model. A novel boundary condition method is used to ensure accurate results in truncated flow branches. Simulations are performed at a steady inhalation flow rate of 18 l min−1, corresponding to a low activity breathing rate, while the effects of particle size and density are investigated. Comparison of the simulation results with available experimental data shows that reasonably accurate results can be obtained at a small fraction of the cost of a full airway model. The simulations clearly evaluate the effect of both particle size and particle density. Most importantly, the results show an improvement over a previously documented single-path model, both in terms of accuracy and the ability to obtain regional deposition rates. The present model represents an improvement over previously used simplified models, including single-path models. The multi-path reduced airway approach described can be used by researchers for general and patient-specific analyses of particle deposition and for the design of effective drug delivery systems.
Highly fluorescent nitrogen-doped graphene quantum dots (N-GQDs) synthesized from Pennisetum purpureum for selective and sensitive detection of Fe3+ ions
Authors: Sari Fathah Dian , Chotimah  , Roto  , Kartini Indriana
Published: July 2023

The synthesis of nitrogen-doped Graphene Quantum Dots (N-GQDs) employing Pennisetum purpureum (elephant grass) as the carbon precursor and ethylenediamine (EDA) as the nitrogen source was conducted. This study highlights the potential applications of nitrogen-doped multi-fluorescent graphene quantum dots (N-GQDs) in the detection of Fe3+. The synthesized N-GQDs have been studied using UV–vis spectrophotometry, fluorescence spectrometry, Raman spectrometry, FT-IR spectrometry, x-ray spectroscopy, selected-area electron diffraction, transmission and high-transmission electron microscopy. The acquired N-GQDs were observed to have an almost hexagonal shape with a lateral size of 2.42 nm and exhibited a comparable quantum yield of approximately 26%. The N-GQDs that have been prepared with consistent size distribution and a significant amount of nitrogen and oxygen-based functional groups showcase outstanding water dispersity. The N-GQDs exhibited the capability to identify the Fe3+ ions in a broad range concentration of 1–600 μM by creating an N-GQDs-Fe3+ complex through the occurrence of functional groups like nitrogen, carbonyl, and carboxyl on N-GQDs surface, has a lower limit of detection at approximately 60 nM. Our study provides evidence that the N-GQDs produced a strong and persistent fluorescence, which is highly soluble in water, notably the precise and selective detection of Fe3+ in water-based solutions.
Assessing thermal ecology of herpetofauna across a heterogeneous microhabitat mosaic in a changing aridland riparian system
Authors: Blais Brian R , Velasco Daniel E , Frackiewicz Marie E , Low Avery Q , Koprowski John L
Published: July 2023

Species–environmental relationships, including drivers of body temperature (T
B), are important for understanding thermal ecology and physiological needs of species during climate change. This is especially important among ectotherms, including amphibians and reptiles (i.e., herpetofauna), in aridland riparian systems. Infrared thermography (IRT) can reliably and noninvasively estimate T
B of ectothermic herpetofauna while simultaneously assessing thermal heterogeneity across a mosaic of microhabitats. We used IRT at a semi-arid riparian zone in Tucson, Arizona to assess herpetofauna–environmental relationships during early-season activity periods in 2020 and 2022. From mixed-effect modeling of desert riparian herpetofauna (n = 81), we found complex environmental relationships influencing T
B. Microhabitat perch surface temperature (T
S) best explained T
B; many ambient conditions were inadequate at capturing T
B. Herpetofauna were as warm by mid-morning than in the early afternoon, with T
B approaching equilibrium with T
S as mornings progressed. Less T
B–T
S variation was detected for anurans (e.g., canyon treefrogs, Hyla arenicolor) than with lizards, supporting that desert amphibians are sensitive to the thermal landscape. There was also complex environmental variation among thermally heterogeneous microhabitats used and available to herpetofauna. As perch T
S increased, shade became more important, though shade sources may be less relevant. The methods and data obtained in this study can serve to establish baselines during seasonally and ecologically important periods and be used to monitor thermal ecology changes across time for herpetofauna or taxa with similar life history in aridland riparian systems. Although ectotherm thermoregulatory functions are undeniably complex, we recommend IRT as a rapid, noninvasive, and complementary tool to monitor cryptic thermal ecology in heterogeneous systems. Understanding species–environmental relationships and monitoring responses of wildlife across time can help guide more effective biodiversity conservation management strategies in a warming and drying world.
Computing error bounds for asymptotic expansions of regular P-recursive sequences
Authors: Dong Ruiwen , Melczer Stephen , Mezzarobba Marc
Published: July 2023

Over the last several decades, improvements in the fields of analytic combinatorics and computer algebra have made determining the asymptotic behaviour of sequences satisfying linear recurrence relations with polynomial coefficients largely a matter of routine, under assumptions that hold often in practice. The algorithms involved typically take a sequence, encoded by a recurrence relation and initial terms, and return the leading terms in an asymptotic expansion up to a big-O error term. Less studied, however, are effective techniques giving an explicit bound on asymptotic error terms. Among other things, such explicit bounds typically allow the user to automatically prove sequence positivity (an active area of enumerative and algebraic combinatorics) by exhibiting an index when positive leading asymptotic behaviour dominates any error terms.

In this article, we present a practical algorithm for computing such asymptotic approximations with rigorous error bounds, under the assumption that the generating series of the sequence is a solution of a differential equation with regular (Fuchsian) dominant singularities. Our algorithm approximately follows the singularity analysis method of Flajolet and Odlyzko [SIAM J. Discrete Math. 3 (1990), pp. 216–240], except that all big-O terms involved in the derivation of the asymptotic expansion are replaced by explicit error terms. The computation of the error terms combines analytic bounds from the literature with effective techniques from rigorous numerics and computer algebra. We implement our algorithm in the SageMath computer algebra system and exhibit its use on a variety of applications (including our original motivating example, solution uniqueness in the Canham model for the shape of genus one biomembranes).
Decomposing the real line into everywhere isomorphic suborders
Authors: Ervin Garrett
Published: July 2023

We show that if

R

=
A
∪
B

\mathbb {R} = A \cup B

is a partition of

R

\mathbb {R}

into two suborders

A
A

and

B
B

, then there is an open interval

I
I

such that

A
∩
I

A \cap I

is not order-isomorphic to

B
∩
I

B \cap I

. The proof depends on the completeness of

R

\mathbb {R}

, and we show in contrast that there is a partition of the irrationals

R

∖

Q

=
A
∪
B

\mathbb {R} \setminus \mathbb {Q} = A \cup B

such that

A
∩
I

A \cap I

is isomorphic to

B
∩
I

B \cap I

for every open interval

I
I

. We do not know if there is a partition of

R

\mathbb {R}

into three suborders that are isomorphic in every open interval.
Vascular variants in seed plants—a developmental perspective
Authors: Cunha Neto Israel L
Published: July 2023

Over centuries of plant morphological research, biologists have enthusiastically explored how distinct vascular arrangements have diversified. These investigations have focused on the evolution of steles and secondary growth and examined the diversity of vascular tissues (xylem and phloem), including atypical developmental pathways generated through modifications to the typical development of ancestral ontogenies. A shared vernacular has evolved for communicating on the diversity of alternative ontogenies in seed plants. Botanists have traditionally used the term ‘anomalous secondary growth’ which was later renamed to ‘cambial variants’ by late Dr. Sherwin Carlquist (1988). However, the term ‘cambial variants’ can be vague in meaning since it is applied for developmental pathways that do not necessarily originate from cambial activity. Here, we review the ‘cambial variants’ concept and propose the term ‘vascular variants’ as a more inclusive overarching framework to interpret alternative vascular ontogenies in plants. In this framework, vascular variants are defined by their developmental origin (instead of anatomical patterns), allowing the classification of alternative vascular ontogenies into three categories: (i) procambial variants, (ii) cambial variants and (iii) ectopic cambia. Each category includes several anatomical patterns. Vascular variants, which represent broader developmental based groups, can be applied to both extant and fossil plants, and thereby offer a more adequate term from an evolutionary perspective. An overview of the developmental diversity and phylogenetic distribution of vascular variants across selected seed plants is provided. Finally, this viewpoint discusses the evolutionary implications of vascular variants.