bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Spatial Model the Contribution of Land Subsidence Caused by Palm Oil Plantations Land Clearing to the Escalating Flood Risk in the Trumon Area, South Aceh Regency, Indonesia
Authors: Alfian Dedy , Meilianda Ella , Ahmad Ashfa , Syukri Muhammad , Opdyke Aaron
Published: January 2024

The Trumon watershed one of critical watershed in Aceh Province had an increase in historical flood episodes during the past 25 years. This is consistent with the expansion of oil palm plantations within the 53,653 Ha watershed basin dominated by peatlands. According to earlier research, changes in land use in peatland regions may cause subsidence. This research looks at the connection between flood events and the subsidence of ground caused by oil palm plantation land clearing. The satellite imagery interpretation reveals a remarkable land use change of previously 5091.25 Ha peatland forest observed in 1995, to become a 13,753.43 Ha palm oil plantation in 2021. From DEMs analysis, those changes are associated with a subsiding land elevation up to 1.23 m. Despite being less than 20% of the watershed area, the land subsidence effect striking change in the watershed boundary, i.e., from only 53,653 Ha to 786,675 Ha which led to an increase in flood inundation from 3,443.04 Ha to 47,924.92 Ha. and flood depth from 0.5 – 1.0 m, to up to 4.0 m. This current situation has made the Trumon area subjected to frequent floods, i.e., from a five-year return period to become an annual event.
Performance of innovative cropping systems diversified with oilseeds and protein crops: identification and resolution of methodological issues, using the Syppre experimental network as a case study
Authors: Longis Sandrine , Cadoux Stéphane , Toupet de Cordoue Anne-Laure , Tauvel Paul , Estienne Marie , Onzon Pierre , Lescourret Françoise , Rouillon Clotilde , Aubertot Jean-Noël
Published: January 2024

Agroecological transition requires that innovative and diversified cropping systems be developed. Conducting system experiments is an approach well-suited to the analysis of performance of cropping systems when subjected to soil, weather and biotic stresses. Conducting system experiments nevertheless gives rise to methodological challenges. Using the Syppre network of experiments, consisting of five sites in France, we present an original case study that provides valuable methodological and agronomic lessons on system experiments. The innovative cropping systems tested there are based on crop diversification (including oilseeds and protein crops), as well as flexible tillage, technical innovations and optimized crop management. From a methodological standpoint, we show that (i) mixed models are adapted to a range of experimental questions and constraints; (ii) multifactorial analysis enables the characterization of relationships between performance indicators; (iii) a multisite experimental network is an efficient approach not only for answering agronomic questions, but also for addressing methodological issues. From an agronomic standpoint, we showed that reconciling multiple indicators of performance is still challenging. Overall, innovative and diversified systems improved the performance of input utilization and environmental impacts, but with lower productivity and profitability. Introducing legume crops is a promising strategy because this contributes significantly to reductions in mineral N fertilizer use, energy consumption and greenhouse gas emissions, without major trade-offs against other performance indicators. Finally, we showed that the nature of the production situation had a major influence on the performance profile. This led us to be cautious in making overall analyses especially with regard to general conclusions.
Analysing the new marketing model for entertainment companies: A case study of SM. entertainment
Authors: Hu Xiaoxiao
Published: January 2024

In recent years, the metaverse have captured the general public’s attention. After so many years of development, the Korean entertainment market has become more and more competitive, and SM Entertainment, as the leading Korean entertainment company, chose to catch the wave of metaverse and create a unique metaverse marketing model, which has been a great success. The aim of the paper was to explore whether SM’s “metaverse” strategy could be a new model for all entertainment companies. This paper investigated the influential factors based on the 4Is of marketing mix theory and through a SWOT analysis. The paper showed that the importance of interest and Interaction is rising in the entertainment market. It concluded that this marketing model has won because of its uniqueness; therefore, other companies cannot replicate its success. If one company wanted to take its place in the competitive market, it would need to have its own unique marketing model.
Predicting the behavior intention of intelligent office software
Authors: Cao Kaiyi
Published: January 2024

In an era where artificial intelligence (AI) is becoming increasingly accessible to the general public, various AI-integrated products have emerged. Microsoft 365 Copilot, developed through collaboration between Microsoft and Chat-GPT, represents a new generation of intelligent office software that combines AI with productivity tools. This research aimed to explore whether intelligent office software will become a future trend in the field of office productivity. The study expanded the application of the Technology Acceptance Model (TAM) to the domain of intelligent software and utilized the SWOT analysis method. The findings of this paper indicated that the design of Microsoft 365 Copilot could enhance Perceived ease of use (PU) and Perceived usefulness (PEOU). The improvement in these factors promoted users’ positive attitudes and behaviors towards the product, thus suggesting that intelligent office software aligns with future development trends. This study provided empirical evidence for the TAM theory in the context of intelligent office software and offers recommendations for the future development of Microsoft 365 Copilot based on the SWOT analysis.
Research on the Selection of the most Popular Product Categories in TikTok based on Linear Regression
Authors: Chen Yue
Published: January 2024

In the e-commerce industry, live streaming has become an increasingly popular way to promote and sell products. With the rise of social media platforms like Facebook, Instagram, and TikTok, more and more businesses are using live streaming to engage with their customers and boost sales. This study investigates the relationship between sales and the number of live viewers to find out the most popular partition for live sales of TikTok’s e-commerce by employing simple linear regression, deseasonalization, and variable transformation techniques to optimize the models. This study improves the accuracy and interpretability of regression models in the e-commerce industry, specifically focusing on the relationship between real-time viewership and Gross Merchandise Volume (GMV). The findings indicate that removing seasonality and applying log-to-log transformation provide more reliable and accurate models, ultimately helping businesses better understand and optimize their sales strategies.
Research on Ideological and Political Teaching Reform of Big Data Foundation and Application Course under the Background of New Business
Authors: Sun Yi
Published: January 2024

Comprehensively promoting the construction of ideological and political courses is a strategic measure to implement the fundamental task of moral education. Colleges and universities should actively carry out the reform of ideological and political courses and integrate them into the whole process of classroom teaching construction. With the development of information technology and the popularization of the Internet, global data shows the characteristics of explosive growth and mass accumulation. With the development of data science and big data technology, China’s big data has made remarkable progress in technology, industry, application and other levels. In this paper, the author studies how to integrate moral education elements into the big data classroom, through in-depth excavation of the ideological and political education elements contained in the professional curriculum, to promote the organic combination of knowledge imparting, ability training, ideals and beliefs, values and beliefs, and moral education, and to integrate ideological and political education into all aspects of professional curriculum teaching, so as to achieve moral education and moisten things silently.
Wie ein neues Mit- statt Nebeneinander in der Psychotherapieforschung
Wissenschaft, Praxis und Weiterbildung verbessern kann
Authors: Schwartz Brian , Gonçalves Miguel M. , Lutz Wolfgang
Published: January 2024

Die kontinuierliche Erhebung psychometrischer Daten vor, während und nach
einer psychotherapeutischen Behandlung kann als
Qualitätssicherungsmaßnahme Therapeut:innen in ihrer klinischen
Arbeit unterstützen und zugleich eine belastbare Datengrundlage für
die Psychotherapieforschung schaffen. Im Rahmen der Qualitätssicherung
können die erhobenen Daten als zusätzliche Informationsquelle den
klinischen Eindruck der Therapeut:innen erweitern und zur Evaluation der Behandlung
am Einzelfall aber auch auf der Ebene des Versorgungssystems herangezogen werden.
Darüber hinaus können prognostische Vorhersagen von
Therapieergebnissen und Abbruchwahrscheinlichkeiten, Behandlungsempfehlungen sowie
adaptive Behandlungsanpassungen während der Behandlung auf ihnen aufgebaut
werden, die Therapeut:innen in ihren klinischen Entscheidungen unterstützen
1. Eine solche daten-gestützte und
evidenzbasierte psychologische Psychotherapie kann die wissenschaftliche Fundierung
der therapeutischen Herangehensweise und die Wirksamkeit der Behandlung verbessern.
Dazu bedarf es umfangreicher Datenerhebungen, die verlässliche und
aussagekräftige Forschungsbefunde ermöglichen 2.
Palliative Urologische Chirurgie des metastasierten Prostatakarzinoms: was müssen wir zukünftig berücksichtigen?
Authors: Heidenreich Axel , Bach Christian , Pfister David
Published: January 2024

Die kombinierte Androgendeprivation mit einem neuen Androgenrezeptor-Biosyntheseinhibitor, dem Zytostatikum Docetaxel oder der Kombination mit Abirateron/Prednison plus Docetaxel bzw. Darolutamid plus Docetaxel stellen die Therapie der Wahl des metastasierten hormonsensitiven Prostatakarzinoms (mHSPC) dar. Trotz des meist guten Ansprechens hat diese Therapie nur einen palliativen Charakter und führt unweigerlich nach durchschnittlich 2,5–4 Jahren zur Entwicklung eines kastrationsresistenten Prostatakarzinoms (CRPC). In diesem Fall stehen neben der klassischen taxanbasierten Chemotherapie, die sekundäre Hormonablation, die Radionuklidtherapie mit Radium 223 oder 177Lu-PSMA als neuere Therapieverfahren zur Verfügung. Aufgrund der dadurch – je nach Therapieansprechen – verlängerten Überlebenszeit gewinnen behandlungswürdige Komplikationen durch das lokal progrediente CRPC, Lokalrezidive oder pelvine Lymphknotenmetastasen zunehmend an Bedeutung.

Treten Komplikationen des unteren Harntrakts wie rezidivierende transfusionspflichtige Makrohämaturien mit oder ohne Blasentamponade, eine subvesikale Obstruktion mit der Notwendigkeit einer Harnableitung oder rektourethrale/rektovesikale Fisteln auf, stehen als palliative chirurgische Therapieoptionen die palliative TUR-P, die radikale (Zysto-)Prostatektomie mit entsprechender Harnableitung sowie die posteriore Exenteration bei rektaler Infiltration zur Verfügung. Bei Harnstauungsnieren aufgrund einer supravesikalen Obstruktion stehen je nach Erlebenserwartung und Allgemeinzustand des Patienten die Anlage einer endoluminalen Ureterschiene oder perkutanen Nephrostomie sowie chirurgisch rekonstruktive Maßnahmen wie die Ureterneuimplantation, Ureter-Ileum-Interponat oder Implantation eines Detour-Systems als Therapieoptionen zur Verfügung.

Letztlich stellt die palliative Tumorchirurgie ein individuelles Therapiekonzept dar, welches bei sorgfältiger Patientenselektion und adäquater chirurgischer Expertise zu einer Verbesserung der Lebensqualität und lokalen Tumorkontrolle führen kann.
Biological Activity of a Coumarin Derivative on Heart Failure Using
an Ischemia/Reperfusion Injury Model
Authors: Figueroa-Valverde Lauro , Rosas-Nexticapa Marcela , Alvarez-Ramirez Magdalena , Melgarejo-Gutiérrez Montserrat , Mateu-Armand Virginia , Garcimarrero-Espino Alejandra
Published: January 2024

Heart failure is a health problem worldwide. There are some drugs for it,
including digoxin, spironolactone, captopril, and valsartan, but some of these
drugs can produce secondary effects, such as arrhythmia, cough, hyperkalemia,
hyponatremia and hypotension. The aim of this research was to evaluate the
biological activity of coumarin (2H-chromen-2-one) and its derivatives
(3BrAcet-C, 3–4Br-Ph-C, 4-CN-7D-C, 4-Me-7-Ph-C and 6Br-3-D-C) against
ischemia/reperfusion injury as a therapeutic alternative for heart
failure. In addition, the biological activity of the coumarin derivative
4-Me-7-Ph-C on left ventricular pressure (LVP) was determined in the absence or
presence of ouabain and nifedipine at a dose of 1 nM using an isolated
rat heart model. The results showed that i) the coumarin derivative
4-Me-7-Ph-C significantly decreased the infarct area
(p+=+0.05) compared with 3BrAcet-C,
3–4Br-Ph-C, 4-CN-7D-C, and 6Br-3-D-C; and ii) 4-Me-7-Ph-C
increased LVP in a dose-dependent manner, which effect was inhibited by
nifedipine. These data suggest that coumarin 4-Me-7-Ph-C may act as a
type-L calcium channel activator, so it could be a good agent to
treat heart failure.
Randomized Comparison of Electronic Health Record Alert Types in Eliciting Responses about Prognosis in Gynecologic Oncology Patients
Authors: Musser Robert Clayton , Senior Rashaud , Havrilesky Laura J. , Buuck Jordan , Casarett David J. , Ibrahim Salam , Davidson Brittany A.
Published: January 2024

Objectives To compare the ability of different electronic health record alert types to elicit responses from users caring for cancer patients benefiting from goals of care (GOC) conversations.

Methods A validated question asking if the user would be surprised by the patient's 6-month mortality was built as an Epic BestPractice Advisory (BPA) alert in three versions—(1) Required on Open chart (pop-up BPA), (2) Required on Close chart (navigator BPA), and (3) Optional Persistent (Storyboard BPA)—randomized using patient medical record number. Meaningful responses were defined as “Yes” or “No,” rather than deferral. Data were extracted over 6 months.

Results Alerts appeared for 685 patients during 1,786 outpatient encounters. Measuring encounters where a meaningful response was elicited, rates were highest for Required on Open (94.8% of encounters), compared with Required on Close (90.1%) and Optional Persistent (19.7%) (p < 0.001). Measuring individual alerts to which responses were given, they were most likely meaningful with Optional Persistent (98.3% of responses) and least likely with Required on Open (68.0%) (p < 0.001). Responses of “No,” suggesting poor prognosis and prompting GOC, were more likely with Optional Persistent (13.6%) and Required on Open (10.3%) than with Required on Close (7.0%) (p = 0.028).

Conclusion Required alerts had response rates almost five times higher than optional alerts. Timing of alerts affects rates of meaningful responses and possibly the response itself. The alert with the most meaningful responses was also associated with the most interruptions and deferral responses. Considering tradeoffs in these metrics is important in designing clinical decision support to maximize success.
Development of the Integrated Computer Simulation Model of the Intracellular, Transmembrane, and Extracellular Domain of Platelet Integrin αIIbβ3 (Platelet Membrane Glycoprotein: GPIIb–IIIa)
Authors: Nakayama Masamitsu , Goto Shinichi , Goto Shinya
Published: January 2024

Background The structure and functions of the extracellular domain of platelet integrin αIIbβ3 (platelet membrane glycoprotein: GPIIb–IIIa) change substantially upon platelet activation. However, the stability of the integrated model of extracellular/transmembrane/intracellular domains of integrin αIIbβ3 with the inactive state of the extracellular domain has not been clarified.

Methods The integrated model of integrin αIIbβ3 was developed by combining the extracellular domain adopted from the crystal structure and the transmembrane and intracellular domain obtained by Nuclear Magnetic Resonace (NMR). The transmembrane domain was settled into the phosphatidylcholine (2-oleoyl-1-palmitoyl-sn-glycerol-3-phosphocholine (POPC)) lipid bilayer model. The position coordinates and velocity vectors of all atoms and water molecules around them were calculated by molecular dynamic (MD) simulation with the use of Chemistry at Harvard Macromolecular Mechanics force field in every 2 × 10−15 seconds.

Results The root-mean-square deviations (RMSDs) of atoms constructing the integrated αIIbβ3 model apparently stabilized at approximately 23 Å after 200 ns of calculation. However, minor fluctuation persisted during the entire calculation period of 650 ns. The RMSDs of both αIIb and β3 showed similar trends before 200 ns. The RMSD of β3 apparently stabilized approximately at 15 Å at 400 ns with persisting minor fluctuation afterward, while the structural fluctuation in αIIb persisted throughout the 650 ns calculation period.

Conclusion In conclusion, the integrated model of the intracellular, transmembrane, and extracellular domain of integrin αIIbβ3 suggested persisting fluctuation even after convergence of MD calculation.
Palladium-Catalyzed Carbothiolation by Using Thioesters with Formation of a Quaternary Carbon
Authors: Nakada Masahisa , Okura Yoshifumi , Ito Ryunosuke , Kumazawa Hyu
Published: January 2024

A Pd-catalyzed carbothiolation using thioesters, with the formation of a quaternary carbon, is described. Carbothiolation using thioesters was problematic due to a direct-coupling side reaction that produced a sulfide, but this side reaction was successfully suppressed by an appropriate selection of the thioester and the reaction conditions. In the preparation of chroman or coumaran derivatives by this method, the reaction using S-phenyl 4-methoxybenzenecarbothioate Pd(PPh3)4, and Cs2CO3 at 100 °C in toluene afforded the desired products in good yields (77–92%). The carbothiolation reaction also proceeded with esters of alkanethiols in higher yields (56–93%) than those obtained from the previously reported carbothiolation using triisopropylsilyl (TIPS) thioethers (12–63%). The developed Pd-catalyzed carbothiolation is applicable in the preparation of a wide range of products, including a tetralin derivative and an indoline derivative. The Pd-catalyzed carbothiolation using thioesters was found to be comparable with a previously reported carbothiolation using TIPS thioethers in terms of the yield and substrate scope, and to be a superior alternative owing to the stability and lower cost of thioesters.
Radiomics-Based Machine Learning Classification Strategy for Characterization of Hepatocellular Carcinoma on Contrast-Enhanced Ultrasound in High-Risk Patients with LI-RADS Category M Nodules
Authors: Li Lingling , Liang Xiaoxin , Yu Yiwen , Mao Rushuang , Han Jing , Peng Chuan , Zhou Jianhua
Published: January 2024

Objective Accurate differentiation within the LI-RADS category M (LR-M) between hepatocellular carcinoma (HCC) and non-HCC malignancies (mainly intrahepatic cholangiocarcinoma [CCA] and combined hepatocellular and cholangiocarcinoma [cHCC-CCA]) is an area of active investigation. We aimed to use radiomics-based machine learning classification strategy for differentiating HCC from CCA and cHCC-CCA on contrast-enhanced ultrasound (CEUS) images in high-risk patients with LR-M nodules.

Methods A total of 159 high-risk patients with LR-M nodules (69 HCC and 90 CCA/cHCC-CCA) who underwent CEUS within 1 month before pathologic confirmation from January 2006 to December 2019 were retrospectively included (111 patients for training set and 48 for test set). The training set was used to build models, while the test set was used to compare models. For each observation, six CEUS images captured at predetermined time points (T1, peak enhancement after contrast injection; T2, 30 seconds; T3, 45 seconds; T4, 60 seconds; T5, 1–2 minutes; and T6, 2–3 minutes) were collected for tumor segmentation and selection of radiomics features, which included seven types of features: first-order statistics, shape (2D), gray-level co-occurrence matrix, gray-level size zone matrix, gray-level run length matrix, neighboring gray tone difference matrix, and gray-level dependence matrix. Clinical data and key radiomics features were employed to develop the clinical model, radiomics signature (RS), and combined RS-clinical (RS-C) model. The RS and RS-C model were built using the machine learning framework. The diagnostic performance of these three models was calculated and compared.

Results Alpha-fetoprotein (AFP), CA19-9, enhancement pattern, and time of washout were included as independent factors for clinical model (all p < 0.05). Both the RS and RS-C model performed better than the clinical model in the test set (area under the curve [AUC] of 0.698 [0.571–0.812] for clinical model, 0.903 [0.830–0.970] for RS, and 0.912 [0.838–0.977] for the RS-C model; both p < 0.05).

Conclusions Radiomics-based machine learning classifiers may be competent for differentiating HCC from CCA and cHCC-CCA in high-risk patients with LR-M nodules.
A Pair of Compound Heterozygous IARS2 Variants Manifesting West Syndrome and Electrolyte Disorders in a Chinese Patient
Authors: Zhou Feiyu , Yi Gui , Liu Xiangyu , Sheng Wenchao , Shu Jianbo , Li Dong , Cai Chunquan
Published: January 2024

Background Aminoacyl-tRNA synthetases (ARSs) are evolutionarily conserved enzymes that ensure the accuracy of the translation process. Isoleucyl-tRNA synthetase 2 (IARS2) gene is a type of ARS that encodes mitochondrial isoleucine-tRNA synthetase. Pathogenic variants in the IARS2 gene are associated with mitochondrial disease which involves several patients presenting broad clinical phenotypes. These clinical phenotypes include West syndrome, Leigh syndrome, and Cataract, growth hormone deficiency, sensory neuropathy, sensorineural hearing loss, and skeletal dysplasia syndrome. Only 29 cases have been reported worldwide. The patient manifested recurrent convulsions, and specific clinical manifestations included electrolyte disorders and recurrent infections.

Methods Whole-exome sequencing was performed on the child with West syndrome. Three-dimensional structure reconstruction and thermodynamic stability prediction were performed to further analyze the relationship between variation and phenotype.

Conclusion This study further expands the clinical spectrum of IARS2 pathogenic variants. The case summaries help raise clinical awareness of IARS2-associated disease and reduce misdiagnosis.

Result In this report, a 13-month-old girl was diagnosed with West syndrome and Leigh syndrome for 7 months. Compound heterozygous variants in the IARS2 gene (NM_018060.4), c.2450G>A (Arg817His) and copy number variation (NC_000001. 11: g. (220267549_220284289) del), were detected by WES. This study further expands the clinical spectrum of IARS2 pathogenic variants. The case summaries help raise clinical awareness of IARS2-associated disease and reduce misdiagnosis.
Ultrafast intrinsic excited state localization m 2D layered As2S3 by interlayer bond formation
Authors: Li Xufeng , Yao Li , Tao Weijian , Zhao Jin , Zhu Haiming
Published: January 2024

The family of two-dimensional (2D) layered materials with strong excitonic effect offers fascinating opportunities for studying excited state exciton behavior at 2D limit. While exciton dynamics in conventional 2D semiconductors (e.g. transition metal dichalcogenides) has been extensively studied, little is known about exciton properties and dynamics in 2D layered semiconductors with strong electron/exciton-phonon coupling. Here, by combining experimental and theoretical approaches, we reveal the intrinsic highly localized exciton (i.e. self-trapped exciton) in 2D layered As2S3, driven by strong exciton-phonon interaction. It is shown that photoexcited electron/hole charges in As2S3 localize spontaneously in ~110 fs, giving rise to large stokes-shifted and broad photoluminescence. An interlayer partial bond is formed between chalcogen atoms, triggering lattice distortion and carrier localization. Together with Urbach-Martienssen analysis, this study provides a comprehensive physical picture to understand the complex interplay between exciton and lattice dynamics in 2D semiconductors, which has strong implications to their optoelectronic properties and applications.
Primary processes in bacterial reaction center revealed by femtosecond broadband fluorescence spectroscopy
Authors: Liu Heyuan , Zhen Zhanghe , Peng Lingfeng , Chen Hailong , Weng Yu-Xiang
Published: January 2024

To gain a deeper understanding of the highly efficient mechanisms within the photosynthetic bacterial reaction center (BRC), we have employed femtosecond broadband fluorescence spectroscopy to investigate the dynamics of initial photo-induced energy transfer and charge separation in BRC at room temperature. Benefiting from the broadband spectral coverage inherent of this technique, two distinct transient emission species associated with bacteriochlorophylls B and P are directly identified, with Stokes shifts determined to be ~197 and 450 cm−1, respectively. The ultrafast energy transfers from bacteriopheophytin H to B (98 fs) and from B to P (170 fs) are unveiled through fitting the emission dynamics. Notably, the anticipated sub-200 fs lifetime of B emission significantly extends to ~400 fs, suggesting a plausible coupling between the electronic excited state of Band the vibronic states of P, potentially influencing the acceleration of the energy transfer process. These findings should pave the way for understanding the impact of vibronic dynamics on the photo-induced primary processes in the photosynthetic reaction center.
Experimental assessment of a morphing trailing edge device for wind turbine blade performance improvement
Authors: Giammichele L. , D'Alessandro V. , Falone M. , Ricci R.
Published: January 2024

Nowadays, wind energy plays a central role in the renewable energy production, and the optimization of wind turbine performance is the focus of current research studies. In this context, morphing trailing edge system could be a promising solution to enhance wind turbine blades' aerodynamic performance. In this paper, an innovative morphing trailing edge system was designed, developed, and tested to improve the performance of a wind turbine blade airfoil. The trailing edge deformation is electrically operated through piezoelectric actuators and a compliant surface. Wind tunnel tests were performed for the sake of system validation at Reynolds number equal to 1.75×105 and 3.5×105 and an angle of attack ranging from −8° to 8°. The results put in evidence the effectiveness of the proposed morphing trailing edge system to enhance the aerodynamic performance. The trailing edge deformation allows to increase or decrease the lift coefficient. The mean percentage difference of lift coefficient was found equal to −83.6% and 68.4% for an upward and downward deflection, respectively. Meanwhile, the drag coefficient does not have a significant variation. Consequently, the aerodynamic efficiency will be increased or decreased keeping the angle of attack unchanged. The mean percentage difference of efficiency was found equal to −83.2% and 77.5% for an upward and downward deflection, respectively. In this way, it would be possible to optimize wind turbine blades' efficiency and production under different operating conditions.
Single-board low-noise fluxgate magnetometer
Authors: Dyer T. , Griffin P. F. , Riis E.
Published: January 2024

Low-noise fluxgate magnetometers are normally comprised of three separate devices: a power supply, the sensor head/electronics and an analog-to-digital converter (ADC). This paper presents a parallel rod fluxgate magnetometer in a single printed circuit board of size=5×12 cm, weight=45 g, and sensor head average power dissipation = 40 mW. The open-loop noise spectral density =5pTrms/Hz@1Hz, competitive with state-of-the-art devices. This is realized using a new amorphous wire core material and programmable mixed-signal electronics with low amplifier and ADC noise. We have compared the sensor performance to a low-noise observatory magnetometer and found sub-nT correlation when tracking the Y (East-West) component of the Earth’s geomagnetic field.
Wavelength-scanning pixel-super-resolved lens-free on-chip quantitative phase microscopy with a color image sensor
Authors: Wu Xuejuan , Sun Jiasong , Chen Yang , Wei Jiahao , Chen Qian , Poon Ting-Chung , Gao Peng , Zuo Chao
Published: January 2024

We report a wavelength-scanning-based lens-free on-chip microscope using a color CMOS sensor and a matching modified phase retrieval algorithm for pixel super-resolution. Compared to traditional monochrome industrial cameras, color sensors favored by the consumer electronics industry have smaller pixel sizes, higher performance, and lower costs. However, the color filtering array (CFA) introduces inherent modulation to the holograms acquired under quasi-monochromatic illumination, which complicates the data processing in lens-free on-chip microscopy. Without physically removing the CFA positioned on the sensor chip, we demonstrate quantitative phase imaging (QPI) with a lateral half-width resolution of 615 nm over a wide field-of-view of 51.88 mm2 by exploiting the green-channel data from Bayer-masked holograms. The resulting spatial bandwidth product is 137.2 megapixels, over 10 times that of a conventional optical microscope. The rationale for using only green-channel data is that the information from each sampling point is not lost during propagation but rather distributed to all pixels in the image. Therefore, the missing data in other channels can be recovered by exploiting the sufficient differences among the raw images captured at different wavelengths. Compared to the scheme with monochrome sensors, this method requires the acquisition of several more images to guarantee the convergence of the algorithm. Experimental results show that we can achieve high-quality QPI performance, thus demonstrating the applicability of cost-effective color sensors in the field of lens-free holographic microscopy.
Development of a microwave chemical cell coupled with post-wall waveguide for in situ/operando soft x-ray absorbance spectroscopy under microwave irradiation
Authors: Fujitani Kaito , Suzuki Satoru , Kishihara Mitsuyoshi , Utsumi Yuichi
Published: January 2024

In this study, we developed a microwave chemical cell for total electron yield soft x-ray absorption spectroscopy (XAS) using synchrotron radiation under microwave irradiation. In addition, in situ XAS measurements of ammonia borane were performed using the device developed. The device comprises a post-wall waveguide housing a sample holder formed within it. Electrons emitted from the sample during soft x-ray irradiation pass through the metal plates of the waveguide and are measured using a picoammeter. Integration of the microwave irradiation structure into a synchrotron radiation beamline, which is a challenge in soft x-ray analysis requiring measurements in a high-vacuum atmosphere, was achieved by miniaturizing the device using 24.125 GHz ISM band microwaves, instead of the typical 2.45 GHz microwaves. Performance of the device was thoroughly assessed through temperature distribution simulation, temperature measurement of water, and evaluation of frequency characteristics. When the sample holder was filled with water and irradiated with 3 W microwaves, the temperature increased to 97 °C, which is close to the boiling point. The in situ XAS measurements performed using this device with ammonia borane/graphite (2:1) powder at the B-K edge during microwave irradiation showed that peaks associated with hydrogen desorption intensified with prolonged microwave exposure. This result indicates that microwave heating in a vacuum and soft x-ray analysis during microwave heating were achieved. The developed microwave chemical cell emerges as a powerful tool, facilitating advancements in our understanding of elementary chemical processes and elucidating microwave-specific effects such as local heating during microwave irradiation.
Invariant dynamics in a united-atom model of an ionic liquid
Authors: Knudsen Peter A. , Heyes David M. , Niss Kristine , Dini Daniele , Bailey Nicholas P.
Published: January 2024

We study a united-atom model of the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl)sulfonylamide to determine to what extent there exist curves in the phase diagram along which the microscopic dynamics are invariant when expressed in dimensionless, or reduced, form. The initial identification of these curves, termed isodynes, is made by noting that contours of reduced shear viscosity and reduced self-diffusion coefficient coincide to a good approximation. Choosing specifically the contours of reduced viscosity as nominal isodynes, further simulations were carried out for state points on these, and other aspects of dynamics were investigated to study their degree of invariance. These include the mean-squared displacement, shear-stress autocorrelation function, and various rotational correlation functions. These were invariant to a good approximation, with the main exception being rotations of the anion about its long axis. The dynamical features that are invariant have in common that they are aspects that would be relevant for a coarse-grained description of the system; specifically, removing the most microscopic degrees of freedom in principle leads to a simplification of the potential energy landscape, which allows for the existence of isodynes.
Effects of hematocrit levels on flow structures and stress levels in the healthy and diseased carotid arteries
Authors: Khan Piru Mohan , Sharma Siddharth D. , Chakraborty Suman , Roy Somnath
Published: January 2024

Flow structures and wall shear stress (WSS) distribution in human arteries depend strongly on blood rheology. Blood viscosity undergoes significant alterations due to varying hematocrit (Hct) levels. Hematocrit levels can change from the normal level (45%) due to numerous disorders such as leukemia, lymphoma, and congenital heart disease. However, the effects of Hct levels on the flow features and WSS levels in large stenotic arteries are not well reported in literature. The present study computationally assesses the variation in flow features in healthy and stenosed carotid arteries due to changes in blood Hct levels. We have reported variations in axial and secondary flow characteristics, vortex structures, and WSS-based parameters for different Hct levels. Specifically, we consider high (65%) and low (25%) Hct levels in addition to a normal Hct level. Our results reveal that both high and low Hct levels have adverse effects on the hemodynamic features inside a healthy carotid artery model. The low Hct level displays a much more widespread low time-averaged WSS (TAWSS) area, while the high Hct shows an increased oscillatory shear index (OSI) zone at the carotid sinus wall. In stenotic arteries, low Hct enhances the spread of the low TAWSS zone in the post-stenotic carotid sinus, whereas high Hct increases the risk of plaque rupture. The high Hct level also increases the spread of high OSI zone at the inner wall of internal carotid artery for the moderately stenosed artery.
Stochastic wave propagation in magneto-thermoelastic materials subjected to the change in electrical and thermal conductivity
Authors: Lotfy Khaled , El-Sapa Shreen , Ahmed Abdelaala , El-Bary Alaa A. , Tantawi Ramadan S. , Ahmed Marwa H. , Elidy Eslam S.
Published: January 2024

This paper presents the results of an investigation that focuses on the stochastic wave propagation that occurs within an elastic medium when the thermoelectric properties are taken into consideration. It has been found that there is a clear association between the characteristics of electrical conductivity and thermal conductivity. As a result, the current topic focuses on the influence a magnetic field has on the variable thermal conductivity and electrical conductivity that exists within a material. This is done within the context of dual phase lag thermoelasticity. Several parameters are incorporated into the governing equations, which exhibit coupling. Thermal shock has been applied to the boundary of the medium that represents the non-traction barrier. At the border of the problem, stochasticity is imposed in order to make the problem appear more realistic. Within the boundary conditions, it is presumed that the white-noise function is present. Utilizing the Laplace transform method is the approach that is taken to address the issue. It is possible to determine the inverse transformations using numerical approximation approaches. Both graphical and visual analyses are performed on the dataset. In conclusion, graphical representations are utilized in order to make comparisons between the deterministic and stochastic solutions of all physical fields.
On predictive models for the equivalent sand grain roughness for wall-bounded turbulent flows
Authors: Abdelaziz Misarah , Djenidi L. , Ghayesh Mergen H. , Chin Rey
Published: January 2024

One of the long-standing goals of rough wall fluid dynamics research is to determine the drag penalty of surfaces based solely on their topographical parameters. The most important length scale or roughness parameter that best describes a surface in relation to friction drag has not been agreed upon yet, despite the many studies that, over the years, have attempted to identify the most appropriate surface parameter. The concept of an equivalent sand-grain roughness (ks) was introduced to standardize different types of roughness in wall-bounded turbulence, serving as an input parameter for predicting the roughness function ΔU+. To anticipate ΔU+ generated by a rough surface under turbulent flow conditions, experts use roughness correlations that establish a correspondence between the topographical characteristics of the surface and ks. Therefore, a chronological compilation of roughness correlations is presented, detailing the parameter ranges and types of roughness used in their development. This study evaluates the effectiveness of predictive correlation functions and aims to formulate a universal function by exploring a comprehensive assortment of three-dimensional (3D) surface textures available in the literature. The results suggest that a correlation based on surface height skewness (ksk) and streamwise effective slope (ESx) can predict the ratio (ks/kq), where kq is the root mean square roughness height for 3D roughness in the fully rough regime. Despite the fact that the correlation is restricted to 3D surface roughness, which is a more realistic representation, the model demonstrated a high level of accuracy in predicting ks for over 120 distinct rough surfaces.
Raman characterization of focused ion beam fabricated lithium niobate film
Authors: You Jingfei , Wu Wei , Jin Chunyan , Qu Lun , Zhang Di , Qi Jiwei , Cai Wei , Ren Mengxin , Xu Jingjun
Published: January 2024

Lithium niobate (LiNbO3, LN) on insulator (LNOI) has emerged as a promising platform for integrated photonics, due to the strong optical confinement and excellent nonlinear optical and electrical characteristics of LN crystal. Focused ion beam (FIB) as a versatile technique has become a typical way to fabricate LNOI microstructures. However, due to the bombardment of Ga+ ions during fabrication, the LN lattice is damaged, which would deteriorate the performance of LNOI devices. Thus, the recognition of the damage formed by FIB fabrication is necessary for the control and optimization of the properties of LN microstructures. However, previous studies on this issue have not delved into it from a lattice perspective. Here, we conducted an investigation into the damage inflicted on LN film due to FIB fabrication and the subsequent impact of buffered oxide etching (BOE) treatment on this damage using Raman spectroscopy. Our findings indicate that the interaction between Ga+ ions and LN film results in lattice amorphization, as well as a reduction in the ionic bonding and lattice stress within LN. Furthermore, absorption spectra were acquired both before and after BOE treatment, revealing the emergence of additional optical losses attributed to Ga+ ions. Notably, these defects responsible for optical losses are predominantly concentrated near the surface of the milled LN film, and BOE treatment proves efficient in their removal. This study contributes to further understanding of the defect structure in LN film after FIB fabrication, as well as repairing the damage and, thus, improving the performance of LN microstructures.
On selection rules in two-dimensional terahertz–infrared–visible spectroscopy
Authors: Seliya Pankaj , Bonn Mischa , Grechko Maksim
Published: January 2024

Two-dimensional terahertz–infrared–visible (2D TIRV) spectroscopy directly measures the coupling between quantum high-frequency vibrations and classical low-frequency modes of molecular motion. In addition to coupling strength, the signal intensity in 2D TIRV spectroscopy can also depend on the selection rules of the excited transitions. Here, we explore the selection rules in 2D TIRV spectroscopy by studying the coupling between the high-frequency CH3 stretching and low-frequency vibrations of liquid dimethyl sulfoxide (DMSO). Different excitation pathways are addressed using variations in laser pulse timing and different polarizations of exciting pulses and detected signals. The DMSO signals generated via different excitation pathways can be readily distinguished in the spectrum. The intensities of different excitation pathways vary unequally with changes in polarization. We explain how this difference stems from the intensities of polarized and depolarized Raman and hyper-Raman spectra of high-frequency modes. These results apply to various systems and will help design and interpret new 2D TIRV spectroscopy experiments.
Evidence of zero group velocity at the lowest dispersion branch through local interactions
Authors: Samak Mahmoud M. , Bilal Osama R.
Published: January 2024

Zero group velocity (ZGV) modes can be utilized in many applications in both optics and acoustics. There exist numerous realizations of metamaterials with ZGVs at higher dispersion branches. However, to engineer the lowest dispersion branch to retain ZGVs, non-local metamaterials with couplings beyond the nearest neighbor are usually at play (i.e., roton-like dispersion). To date, there exists no realization of roton-like dispersion for the lowest branch without non-local couplings. Non-locality, while rich in dynamics, can render designs rather complex. Here, we provide the first experimental evidence of a ZGV point for the lowest dispersion branch within the first Brillouin zone with local interactions. We utilize nonlinear magnetic lattices as a platform to sculpt our dispersion. Our findings might enable the realization of exotic metamaterials with simple designs.
Proton doping enhanced flexoelectricity and photocurrent in hydrogen-charged TiO2
Authors: Wang Z. L. , Jin Yangshi , Suen Chun Hung , Mao Chenyue , Gong Xiangnan , Ma Jiangping , Hong J. W. , Zhang F. , Wong Chi-Ho , Chen W. P. , Zhou X. Y. , Dai Ji-Yan
Published: January 2024

The intrinsic flexoelectric effect observed in oxide materials often falls below the desired threshold for practical applications. In this work, we demonstrate proton doping in insulating rutile TiO2 crystal as an effective approach to significantly increase flexoelectricity by more than two orders of magnitude. We attribute the noteworthy enhancement of flexoelectricity to the dual impact of proton doping in oxide materials. First, proton doping serves to induce the presence of charge carriers, resulting in the generation of flexoelectric currents. Second, proton doping induces expansion and distortion of the lattice structure, leading to an amplified flexoelectric field when the crystal experiences a strain gradient. The formation of O–H bonding in TiO2 crystal provides another route to break centrosymmetry according to lattice distortion of the TiO2 lattice, resulting in a larger flexoelectric field. In addition, the introduction of proton doping in TiO2 single crystals leads to a substantial increase in photocurrent by effectively flattening the interfacial Schottky junction. This phenomenon results in a three-order of magnitude enhancement of the photocurrent. Our work broadens the horizon of study on dielectric materials through proton doping and may also provide an approach that enables the utilization of dielectric materials in energy conversion applications.
A dominant dimensionless number and theoretical model for the evolution of multiphase Richtmyer–Meshkov instability
Authors: Si Yingming , Li Shuai , Meng Baoqing , Wang Chun , Tian Baolin
Published: January 2024

Multiphase Richtmyer–Meshkov instability (RMI) is often accompanied by a dispersed phase of particles, where the evolution of the mix zone width (MZW) is a significant issue. The Stokes number (St) is a key dimensionless parameter for particle-containing multiphase flows because it represents the ability of particles to follow the fluid. However, our theoretical analysis and numerical simulation indicate that the Stokes number is not the only dominant parameter for the evolution of multiphase RMI. This study uses the derivation of particle and fluid momentum equations to demonstrate the inability of the Stokes number to predict MZW evolution, that is, even at the same Stokes number, increasing the particle density or the radius leads to completely different MZW evolution trends. This study proposes a novel dimensionless number, Sd, to measure the effect of drag on the fluid owing to the particles. Sd is the ratio of the relaxation time of the fluid velocity affected by the particle force to the characteristic time of the shock wave. We developed theoretical models of MZW at different Sd values. Subsequently, a set of multiphase RMI numerical simulations on uniformly distributed particles with different St and Sd values was conducted. The numerical results verify the theoretical predictions and effectiveness of the proposed dimensionless number. The phase diagram containing different simulation cases demonstrates that the Stokes number cannot be used to predict MZW and must be combined with Sd to determine its evolution.