bluuebunny/crossref_metadata_2025 huggingface dataset:
Signal Fading in Radio Communications
Authors: Janaswamy Ramakrishna
Published: November 2024

In this article we describe the causes of signal fluctuation in wireless systems and describe the phenomena of short‐term and long‐term fading. Some of the topics included are narrowband and wideband fading, Rayleigh fading, Ricean fading, lognormal fading, level crossing rates, average fade duration, channel coherence time, Doppler spread, delay spread, and coherence bandwidth. The impact of fading on the performance of systems and in the design of cell size is discussed.
Direct Satellite Television Broadcasting
Authors: Godwin John P.
Published: November 2024

Direct‐to‐home (DTH) satellite television broadcasting has no strict technical or legal definition. Since the late 1970s the term has been used to delineate commercial systems that deliver television directly to consumer homesusing communication satellites in geosynchronous orbit.

This article describes the broadcasting and reception systems of a typical digital DTH broadcasting system, but does not cover the substantial infrastructure necessary for customer service and billing.
Galerkin Method (Rayleigh–Ritz Method)
Authors: Weile Daniel S. , Wildman Raymond A. , Pisharody Greeshma , Mohan Anuraag
Published: November 2024

Galerkin's method and the Rayleigh–Ritz method form the mathematical underpinnings of many modern computational techniques for the solution of electromagnetics problems. In this work, the history of these two methods is reviewed, and each of the methods is described in detail. The relationship between the methods is explored, as is their relationship with the modern finite‐element method and method of moments. Numerical examples of the methods are provided to clarify the exposition.
Integro‐Differential Equations
Authors: Garcia Manuel
Published: November 2024

This article discusses a variety of methods and approximations used to solve and calculate integrodifferential equations, with emphasis, is on the utilitarian rather than the theoritical. Integrodifferential equations can describe linear and nonlinear systems that have memory, or are not in equilibrium. The appearance of both derivatives and integrals in an equation (e.g., expressing some type of balance with respect to time) means that instantaneous rates (e.g., velocity) and accumulated history (e.g., metal fatigue) determine the state of the system at the present moment. It is this aspect of integrodifferential equations that gives them their intellectual appeal, wide applicability, and challenging nature.
Electromagnetic Ferrite Tile Absorber
Authors: Holloway Christopher L. , Baker–Jarvis James R. , Johnk Robert T. , Geyer Richard G.
Published: November 2024

In this chapter, we discuss the ferrite tile, ferrite grids, and hybrid combinations of urethane and ferrite absorbers typically used in electromagnetic test chambers for the 30MHz to 1000MHz frequency range. We present formulas and calculated reflectivities (or reflection coefficients). We also discuss how material properties and reflectivities are measured for the ferrite‐tile absorbers.
Cavity Resonators
Authors: Sharma Arvind K.
Published: November 2024

In this article, a brief description of the cavity resonators most commonly employed in various microwave components is presented. As far as possible, simple expressions have been provided for design applications. Basic parameters of microwave resonators are first presented because they describe a cavity. Then, various coaxial and waveguide resonators are described. Fabrication, coupling, measurements, and applications of cavity resonators are also included.
Coupled Transmission Lines
Authors: Paul Clayton R.
Published: November 2024

Two transmission lines whose electromagnetic fields are coupled induce signals from one line into another. This coupling is either intentional as in directional couplers or unintentional, producing unwanted responses in the other line, which is referred to as crosstalk. This discussion of coupled transmission lines will concentrate on the analysis of coupled lines and can be used to design intentional coupling or to assess unintentional coupling as in crosstalk.
Maxwellian Circuits
Authors: Mei Kenneth K.
Published: November 2024

A Maxwellian circuit is defined as a discretized equivalent circuit of a wire structure, the solution of which is the same as that of the Maxwell's equations satisfying the same boundary conditions of the circuit. The theory of Maxwellian circuits is based on the existence and uniqueness theorems of equivalent differential equations of each thin‐wire‐type integral equation, which is derived from Maxwell's equations. In this article, the proofs of the basic theorems are presented, calculations verifying the theory are shown in figures, and related applications are discussed.
Microwave Power Amplifiers
Authors: Colantonio Paolo , Giannini Franco , Limiti Ernesto
Published: November 2024

Microwave Power are discussed, focusing mainly on solid‐state implementations. Starting with an introduction on solid‐state and vacuum device power generating capabilities and solid‐state active realization technologies and materials, this article introduces and defines the basic quantities defining and characterizing a microwave power amplifier. The basic concepts of operating class and the relevant expected performances are addressed, including reference cases. Power balance considerations are inferred and high‐efficiency power amplifier design techniques are detailed, including both harmonic tuning approaches and switched‐mode amplifier schemes. Measurement‐based approaches (load pull) and computer‐aided design techniques are also discussed.
Periodic Structures
Authors: Bozzi Maurizio
Published: November 2024

This article gives an overview of periodic structures commonly used in the microwave and millimeter‐wave frequency range. The operation principle of the most significant components, their applications and the classical fabrication technologies are described. The basic theory of the propagation of electromagnetic fields in periodic structures is reported, and includes Floquet's theorem and Brillouin zones. Some numerical methods typically adopted for their analysis are described and discussed.
Power Combiners and Dividers
Authors: Bialkowski Marek E. , Tsai Feng-Chi E.
Published: November 2024

The article provides an extensive review on the topic of microwave and millimeter‐wave power combiners and dividers. Because many power combining and dividing structures can be used interchangeably, the review focuses on power combiners. It commences with an introduction of power combining principles and grouping of power combiners into suitable categories. The main categories considered here include circuit‐level (both resonant and nonresonant type) and space‐level power combiners. Next, operation and fundamental characteristics of circuit and space‐level combiners, which have been presented in the microwave literature, are thoroughly explained. In the subsequent sections, analysis methods for power combiner/divider structures are described. They concern both circuit and electromagnetic field approaches. The use of state‐of‐the art computer software for the analysis of power combining/dividing structures is also covered. The last section of the article is concerned with applications of power combiner/dividers in modern communication and radar systems. Examples of most impressive power combiners of solid‐state devices, in terms of an achieved output power level or highest frequency of operation, are presented. The review concludes with remarks on recent progress in the field of space‐level combiners.
Resonators
Authors: Ahn Hee-Ran
Published: November 2024

Resonators are important components in microwave communication circuits. They create filters and select frequencies in oscillators, amplifiers, tuners, and so on. Fields inside a resonator store energy at the resonance frequency where equal storage of electric and magnetic energies occurs. The input impedance at resonance is purely real because the reactance is proportional to the difference between electric and magnetic energy storage.

In this article, series and parallel resonance circuits will be discussed and then the representative resonators that are commonly used in practical cases will be explained.
Skin Effect
Authors: Olyslager Frank , de Zutter Daniël
Published: November 2024

The skin effect is the property that electromagnetic waves penetrate only a small distance into a conductor. The fields and induced currents decay exponentially with the distance from the surface. The distance over which the fields and induced currents decrease by a factor ofeis the skin depth. The ratio of the voltage drop along the surface of the conductor to the current flowing in the conductor and causing this voltage drop is the surface impedance. Expressions for the skin depth and the surface impedance are in the first instance derived for a plane conductor interface. The results for a plane conductor are also applicable for a curved conductor as long as the radius of curvature is large compared to the wavelength. For a conductor with a finite thickness an expression for the surface impedance is derived that takes into account the finite thickness of the conductor. The roughness of the conductor surface increases the surface resistance. This increase is quantified by an empirical law. The concept of the surface impedance allows an efficient inclusion of conductors with finite conductivity in numerical electromagnetic simulation techniques such as integral equation techniques, finite‐element techniques, and finite‐difference time‐domain techniques.
Strip Transmission Lines
Authors: Pramanick Protap , Bhartia Prakash
Published: November 2024

Striplines are one of the most common types of transmission lines used in microwave circuits. This article presents the fundamental characteristics of this transmission line, together with equations for calculating these. Striplines are useful for designing virtually all microwave circuit components, which are described in the article.
Radar Applications
Authors: Tsihrintzis George A.
Published: November 2024

Radar (radiodetection andranging) systems attempt to infer information about remotely located objects from reflections of deliberately generated electromagnetic waves at radio‐ and microwave frequencies. Typically, the information sought is detection of the presence of target objects in the midst of clutter, recognition (classification) of targets, and estimation of target parameters such as range distance from the radar antenna), bearing (azimuth and elevation), orientation, velocity, acceleration, or backscattering cross section (reflectivity) distribution. Today's radar systems perform these tasks for multiple targets simultaneously, at the finest possible target resolution and with the highest possible accuracy. Additionally, the domain of utilization of radar techniques has expanded beyond the traditional aircraft detection and ranging application. Indeed, modern radar applications include search, tracking, and navigation radar for spread targets, high‐resolution aerial imaging radar, weather observation radar, and ground‐ and foliage‐penetrating radar. To achieve their expanded tasks, modern radar systems combine high‐quality hardware with sophisticated signal design and processing algorithm development and implementation based on statistical descriptions of both the target characteristics and the clutter distributions.
Digital Radio
Authors: Aalo Valentine A.
Published: November 2024

This article presents an overview of digital radiocommunications with emphasis on wireless personal communications.

The main objective of wireless personal communication is to allow the user access to the capabilities of the global network at any time and without regards to location and mobility.

Digital radio, used extensively in second‐generation and the evolving third‐generation systems, considerably improves the quality of the cellular system and enhances the services available to the mobile subscribers.
Radar Signal Processing
Authors: Ye Wei , Yeo Tat Soon
Published: November 2024

Signal processing plays a key role in most modern radar operations. Radar signal processing commonly refers to the techniques that are used to extract desired information about a target from the received signals. Such information usually includes target presence and the position, velocity, trajectory, and image of the target.
Feedback Amplifiers
Authors: Schubert Thomas F.
Published: November 2024

This article considers the benefits of negative feedback on amplifier design: stabilization of gain, reduction of nonlinear distortion, increased bandwidth, and selective modification of input and output resistance. Basic definitions are followed by a general discussion of the properties of a feedback system. Amplifiers are divided into four categories of feedback topology, and the specific properties of each topological type are determined. The drawbacks of feedback, reduction of gain, and the possibility of oscillation are also considered. Several compensation methods to improve amplifier stability are discussed.
RF Circuit Noise
Authors: Marshall Leach W.
Published: November 2024

The
V
n
−
I
n
noise model of an amplifier is described. The model is used to define signal‐to‐noise ratio and noise factor. The optimum source impedance that minimizes the noise factor is derived. The effect of matching networks on noise factor is described. Two lossless matching network examples illustrate how the source impedance can be transformed to minimize the noise factor. The use of Smith chart noise circles and gain circles to evaluate amplifier performance is described and illustrated by an example. Measurement of noise factor and a method of determining amplifier noise parameters from noise factor measurements are described.
Evaluating the origin and spread of spotted lanternfly (Lycorma delicatula) in Japan
Authors: Kamiyama Matthew T. , Takahashi Michihiko , Broadley Hannah J. , Gómez‐Marco Francesc , Hoddle Mark S. , Matsuura Kenji
Published: November 2024

Spotted lanternfly Lycorma delicatula is an emergent invasive agricultural pest native to China, and has invaded the Republic of Korea ([i.e., South Korea] first detected 2006), Japan (2009), and the United States of America (2014). Previous reports from the Republic of Korea and the United States on L. delicatula detail rapid population expansion and severe feeding damage to crop and non‐crop host plants following its invasion. In contrast, populations in Japan initially spread slowly and remained isolated to two prefectures (Ishikawa and Fukui) for 8 years post‐invasion without any reports of agricultural damage. Here we update the current known distribution of L. delicatula in Japan through field surveys and complete a comprehensive review of formally published literature and community scientist reports. Recently L. delicatula has expanded its range in Japan with six new prefectural detections in the last 2 years. Phylogenetic analyses were performed using whole mitochondrial genome sequences of specimens collected across Japan to elucidate the genetic makeup and potential source areas of these populations. Phylogenetic analyses suggest the putative area of origin of Japanese L. delicatula populations is the north‐central region of China, as opposed to the invasive populations in the Republic of Korea and in the United States, which both originate from the eastern region of China. Results presented here provide a better understanding of the factors influencing the invasion dynamics of L. delicatula, which could enable development of improved biosecurity, monitoring, and incursion management programs for this pest.
Commissioning of a commercial treatment planning system for scanned carbon‐ion radiotherapy
Authors: Sun Wei , Wang Weiwei , Huang Zhijie , Zhao Jingfang
Published: November 2024

Purpose

To commission the RayStation (RS) TPS (treatment planning system) for scanned CIRT (carbon‐ion radiotherapy) utilizing pencil beam algorithms (PBv4.2).

Methods

The beam model commissioning entailed employing 1D single beams and 2D monoenergetic fields to validate spot profiles with films, assess beam range using Peakfinder measurements, and evaluate fragment spectra through dose‐averaged linear energy transfer (LETd) calculations. 3D dose distributions were verified in homogeneous phantoms for both absorbed and relative biological effectiveness (RBE)‐weighted doses, and further assessed in double wedge and anthropomorphic phantoms for absorbed dose only. Finally, RBE‐weighted dose verification and patient‐specific quality assurance were conducted using 58 beams from 20 clinically treated patient plans.

Results

The results demonstrated good agreement in absolute dose distribution between TPS calculations and measurements, with mean dose discrepancies within 3%. However, deviations were slightly higher (> 1%) for the cases involving the range shifter (RaShi) compared to those without the RaShi (< 1%). Beam range, depth dose distribution, and lateral profiles of spread‐out Bragg peaks (SOBPs) closely matched between RS TPS calculations and measurements. Some discrepancies (less than 0.5 mm) were observed at field edges and in penumbra regions due to limitations in simulating asymmetrical spots, but within clinical tolerance. After model tuning, RBE‐weighted dose calculations in RS TPS were in agreement with those from the clinically used TPS, except for variations exceeding 3% observed at energies exceeding 408.07 MeV/u, primarily attributed to fragment spectra differences.

Conclusion

Overall, this study validated the RS TPS for calculating absorbed doses against measurements and RBE‐weighted doses against a clinically used TPS. The results suggested that the RS TPS could be utilized for CIRT treatment planning, except for energies exceeding 408.07 MeV/u.
Diarylethene Molecular Clocks for Dual‐Mode Time‐Dependent Data Encryption
Authors: Liu Jie , Liang Baoshuai , Dong Yu , Wu Huacan , Zhang Chuang , Pei Haizhou , Zuo Mengdi , Yu Xiaolan , Zheng Shiya , Feng Shiyu , Huang Weiguo
Published: November 2024

Developing dynamic encryption materials with time‐dependent outputs has gained importance in the digital age. While many studies have introduced phosphorescent, polymeric, and/or self‐assembled materials for this purpose, challenges such as poor handleability, short readout duration, and single‐mode output persist. To address these issues, designed three photochromic molecules—DAE‐B, DAE‐NH, and DAE‐N with different photoisomerization rates are designed. Under 254 nm irradiation, DAE‐B and DAE‐NH appear magenta per cyclization, while DAE‐N emits orange fluorescence. Notably, DAE‐B and DAE‐NH are visible under both visible light and UV light (254 and 365 nm), whereas DAE‐N is visible only under UV light. Leveraging these properties, a time‐dependent dynamic encryption system using DAE‐B and DAE‐NH is developed, where the correct message is accessible only at a specific time, while wrong information would appear at other time points. Additionally, by integrating DAE‐B, DAE‐NH, and DAE‐N into QR codes (quick‐response code), and combining this with the scanning sequence, time, and wavelength, a dual‐mode, 3D encryption system that operates under both visible and UV light is created. This innovation not only advances time‐based encryption techniques but also contributes to the development of molecular clock‐based encryption materials.
Synergistic Redox Dual‐Site Strategy to Boost Photosynthesis of Hydrogen Peroxide
Authors: Zhang Rongao , Xu Haonan , Huang Zixiang , Zhang Jing , Liu Limin , Ma Zhentao , Zhang Zhilin , Wang Kun , Liu Peigen , Liu Huarong , Zheng Xusheng
Published: November 2024

Graphitized carbon nitride (C3N4)‐based photocatalysts provide a prospective approach for producing hydrogen peroxide (H2O2) in artificial photosynthesis. However, their activity is constrained by the sluggish water oxidation reaction (WOR) process, which hampers the supply of protons and electrons necessary for the oxygen reduction reaction. Here, this work demonstrates a synergistic redox dual‐site strategy via co‐modified with 3,4,9,10‐perylenetetracarboxylic acid diimide (PDI) and Pt single atoms in C3N4 support, which achieves an exceptional H2O2 yield of 802 µmol g−1 h−1 and a selectivity of 91.8% without sacrificial agents. Mechanistic studies reveal that Pt single atoms act as photogenerated electron‐rich sites to effectively activate O2 to form superoxide radicals, and PDI promotes WOR driving force to provide abundant protons. The optimized reduction and oxidation half‐reactions improve the proton‐coupled electron transfer process, thereby enhancing the selective photosynthesis of H2O2. This work underscores the importance of finely controlling half‐reactions in photocatalytic processes to promote efficient and synergistic overall reactions.
Red Multi‐Resonant Thermally Activated Delayed Fluorescence Emitters as Bioimaging Agents
Authors: Si Changfeng , Primrose William L. , Xu Yan , Hudson Zachary M. , Zysman‐Colman Eli
Published: November 2024

Multi‐resonant thermally activated delayed fluorescence (MR‐TADF) emitters have attracted strong interest for organic electroluminescent devices due to their high photoluminescence quantum yield (ΦPL) and narrowband emission. These properties are also crucial for high‐performance biological probes, especially red emitters. Orange and red MR‐TADF emitters, PhDPA‐DiKTa and MeODPA‐DiKTa, are designed by decorating the DiKTa core with di([1,1′‐biphenyl]‐4‐yl)amine and bis(4‐methoxyphenyl)amine, respectively. As 5 wt.% doped films in 1,3‐di(9H‐carbazol‐9‐yl)benzene (mCP), PhDPA‐DiKTa emits at λPL of 617 nm, while MeODPA‐DiKTa emits at λPL of 655 nm. Both show delayed fluorescence, with delayed lifetimes, τd, of 658.4 and 249.2 µs, respectively. Water‐dispersible glassy organic dots (g‐Odots) based on these materials are prepared by encapsulating them and mCP host into an amphiphilic DSPE‐PEG2k polymer. Both families of g‐Odots showed a deeper red emission and enhanced ΦPL compared to the corresponding 5 wt.% doped films in mCP (λPL = 618 nm, ΦPL = 77% for PhDPA‐DiKTa g‐Odots, λPL = 663 nm, ΦPL = 38% for MeODPA‐DiKTa g‐Odots). The TADF character of the emitters is conserved in the g‐ODots, with τd of 203.9 µs for PhDPA‐DiKTa g‐Odots and 131.6 µs for MeODPA‐DiKTa g‐Odots. These MR‐TADF g‐Odots are successfully demonstrated as biological imaging probes of HeLa cells.
Understanding and Circumventing Failure Mechanisms in Chalcogenide Optical Phase Change Material Ge2Sb2Se4Te
Authors: Popescu Cosmin Constantin , Aryana Kiumars , Mills Brian , Lee Tae Woo , Martin‐Monier Louis , Ranno Luigi , Sia Jia Xu Brian , Dao Khoi Phuong , Bae Hyung‐Bin , Liberman Vladimir , Vitale Steven A. , Kang Myungkoo , Richardson Kathleen A. , Ríos Ocampo Carlos A. , Calahan Dennis , Zhang Yifei , Humphreys William M. , Kim Hyun Jung , Gu Tian , Hu Juejun
Published: November 2024

Chalcogenide optical phase change materials (PCMs) have garnered significant interest for their growing applications in programmable photonics, optical analog computing, active metasurfaces, and beyond. Limited endurance or cycling lifetime is however increasingly becoming a bottleneck toward their practical deployment for these applications. To address this issue, a systematic study elucidating the cycling failure mechanisms of Ge2Sb2Se4Te (GSST) is performed, a common optical PCM tailored for infrared photonic applications, in an electrothermal switching configuration commensurate with their applications in on‐chip photonic devices. Further a set of design rules building on insights into the failure mechanisms is proposed, and successfully implemented them to boost the endurance of the Ge2Sb2Se4Te (GSST) device to over 67 000 cycles.
Theoretical and Experimental Optimization of P2‐Type Sodium‐Ion Battery Cathodes via Li, Mg, and Ni Co‐Doping: A Path to Enhanced Capacity and Stability
Authors: Cho Man‐Jae , Yaqoob Najma , Yu Jun Ho , Köster Konstantin , Kim A‐Yeon , Jung Hun‐Gi , Ihm Kyuwook , Lee Kug‐Seung , Avdeev Maxim , Kim Hyungsub , Kaghazchi Payam , Myung Seung‐Taek
Published: November 2024

Understanding the oxygen‐redox reactions within Mn‐rich layered cathode materials is an important strategy to improve the capacity of sodium‐ion batteries (SIBs) while satisfying the demand for low cost and the use of abundant resources. Nonetheless, the P2‐type Nay[AxMn1‐x]O2 compositions (where A = electro‐inactive elements) exhibit poor capacity retention and low operation voltage along with a broad voltage hysteresis. In addition, Nay[TMxMn1‐x]O2 (where TM = transition metal) still suffers from low capacity in the absence of anion redox activity. This investigation introduces Li, Mg, and Ni into the P2‐layered NaxMnO2 matrix to explore diverse compositional dynamics engineered by density functional theory and ab initio molecular dynamics. The P2‐Na0.7[Li0.1Mg0.05Ni0.15Mn0.7]O2 configuration is optimized, exhibiting enhanced structural and electrochemical stabilities. Operando X‐ray diffraction analyses affirm the preservation of the P2 structure throughout de/sodiation, and comprehensive structural analyses unraveled the complex charge‐compensation mechanisms facilitated by Ni2+/Ni4+, Mn3+/Mn4+, and O2−/(O2)n− redox pairs. Neutron diffraction and nuclear magnetic resonance techniques elucidate the Li migration phenomena within the TM and sodium layers. This research underscores the pivotal role of Li, Mg, and Ni co‐doping in the development of cathode materials, paving the way for SIBs with enhanced electrochemical performance.
Alcohol Self‐Aggregation: the Preferred Configurations of the Ethanol Trimer
Authors: Indira Murugachandran S. , Peña Isabel , Mokhtar Lamsabhi Al , Yáñez Manuel , Eugenia Sanz M.
Published: November 2024

An atomic‐level knowledge of the aggregation of archetypal molecular systems is essential to accurately model supramolecular structures and the transition from gas to liquid phase. The structures and forces involved in ethanol aggregation have been investigated using microwave spectroscopy and extensive quantum chemical calculations. Four isomers of the ethanol trimer have been observed and identified based on comparisons between experimental and predicted spectroscopic parameters, and considering collisional relaxation in the supersonic expansion. All observed isomers exhibit O−H
O hydrogen bonds between the hydroxyl groups forming a six‐membered ring. Additionally, secondary C−H
O hydrogen bonds and H
H dispersion contacts participate in the stabilization of the complexes with remarkably similar energy contributions. Structures where there is a mixture of gauche and trans conformations of ethanol are favored, with gauche conformations being predominant and no evidence of homochirality synchronization. Our results underscore the critical changes involved in aggregation as the size of the system increases and shed light on the unique properties and behavior of ethanol in chemical and biological systems.
Selection of Plastic‐Binding DNA Aptamers for Microplastics Detection
Authors: Zandieh Mohamad , Luo Xin , Zhao Yu , Feng Chuanliang , Liu Juewen
Published: November 2024

Plastics are critical materials for modern technological applications, yet environmental contamination by microplastics has become a growing concern. In this study, DNA aptamers were isolated for two of the most abundant plastic materials: polyvinylchloride (PVC) and polystyrene (PS). These aptamers contain approximately 90 % cytosine and thymine but only 10 % purine content. Among them, the PVC‐1 aptamer binds to PVC with a six‐fold higher capacity than a random sequenced DNA. Among the tested plastic materials, PVC and PS exhibited the highest specific binding capacity. Using fluorophore‐labeled PVC‐1 aptamer, PS/PVC microplastics as low as 1 mg were detected, and the aptamer was selective for microplastics over other environmentally relevant materials, such as silica. Molecular dynamics simulations indicated that the aptamer attempted to maximize contact with the plastic surface for adsorption. This plastic‐binding aptamer is expected to find applications in environmental monitoring and has fundamental implications for surface‐binding aptamers.
Detecting Interactions in High‐Dimensional Data Using Cross Leverage Scores
Authors: Teschke Sven , Ickstadt Katja , Munteanu Alexander
Published: November 2024

We develop a variable selection method for interactions in regression models on large data in the context of genetics. The method is intended for investigating the influence of single‐nucleotide polymorphisms (SNPs) and their interactions on health outcomes, which is a problem. We introduce cross leverage scores (CLSs) to detect interactions of variables while maintaining interpretability. Using this method, it is not necessary to consider every possible interaction between variables individually, which would be very time‐consuming even for moderate amounts of variables. Instead, we calculate the CLS for each variable and obtain a measure of importance for this variable. Calculating the scores remains time‐consuming for large data sets. The key idea for scaling to large data is to divide the data into smaller random batches or consecutive windows of variables. This avoids complex and time‐consuming computations on high‐dimensional matrices by performing the computations only for small subsets of the data, which is less costly. We compare these methods to provable approximations of CLS based on sketching, which aims at summarizing data succinctly. In a simulation study, we show that the CLSs are directly linked to the importance of a variable in the sense of an interaction effect. We further show that the approximation approaches are appropriate for performing the calculations efficiently on arbitrarily large data while preserving the interaction detection effect of the CLS. This underlines their scalability to genome wide data. In addition, we evaluate the methods on real data from the HapMap project.
Analyzing Quinoa Seeds: LC–MS/MS and GC–MS/MS Approaches for Identifying a Nutrient‐Rich Functional Food in Alzheimer's and Diabetes Care
Authors: Çoban Furkan , Yuca Hafize , Aydın Bilge , Tosun Murat , Yazıcı Abdullah , Karakaya Songül , Tan Mustafa , Özer Hakan , Atila Alptuğ
Published: November 2024

Quinoa is a versatile, nutrient‐dense, gluten‐free pseudocereal, increasingly recognized for its potential health benefits, particularly in managing diabetes mellitus and Alzheimer's disease—two conditions with growing links. Recent research on 14 quinoa genotypes explored fatty oil composition and bioactive potential of quinoa extracts. Linoleic acid was predominant fatty acid (46.60%–56.33%), whereas alanine was the most concentrated amino acid across all active extracts (192.4887–1578.0355 nmol/mL). French Vanilla hexane extract exhibited the strongest α‐glucosidase inhibition (75.71%), with Santa Ana hexane extract showing the highest α‐amylase inhibition (28.58%). Additionally, Titicaca hexane extract displayed notable acetylcholinesterase inhibition (22.22%), and Moqu Arochilla methanol extract had the most potent butyrylcholinesterase inhibition (47.20%). Antioxidant assays revealed that Salcedo and French Vanilla extracts had exceptional 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity, with positive correlations found between total phenolic content and antioxidant activity (DPPH, β‐carotene, FRAP). These findings emphasize quinoa's potential as a functional food, offering significant benefits for disease management.
Optimizing passive micromixers: Enhancing mixing efficiency through computational fluid dynamics and metaheuristic algorithms
Authors: Mustafa Md Gulam , Zunaid Mohammad , Gautam Samsher
Published: November 2024

This paper examines the optimization of micromixers, highlighting their essential role in improving the efficiency of chemical reactions and fluid mixing at a micro‐scale, and using metaheuristic algorithms for a novel passive micromixer featuring bends and twists with offsets. The twists and bends cause constant changes in the direction of liquid flow, leading to chaotic advection that enhances species mixing while minimizing pressure loss. Although increasing channel length generally improves mixing performance, the proposed design's performance was higher than the reference channel for Reynolds numbers (Re) greater than 100. Key findings include achieving an excellent mixing performance of 87.76% at a Reynolds number of 400, with a bend angle of 60° and a twist factor of 4. The Harris hawk optimization (HHO) algorithm proved the most effective for optimizing microfluidic channel designs. This approach offers significant advantages for cost‐effectively optimizing microfluidic channel designs.
Crystal Structure of Ritonavir Polymorphs I and II Revisited with the Application of NMR Crystallography
Authors: Szeleszczuk Łukasz , Gubica Tomasz , Maciej Pisklak Dariusz
Published: November 2024

Ritonavir, a protease inhibitor sold under the brand name Norvir®, is an antiviral medication that effectively targets the human immunodeficiency virus (HIV). Being probably the most important and best‐known example of the crystal polymorphism in the field of pharmaceutics, ritonavir has been extensively studied in the last 30 years, which eventually led to the discovery of its new polymorph, Form III, in 2023. So far, two crystal structures of both Forms I and II of ritonavir were deposited in CCDC database. The aim of this study was to revisit those crystal structures, using NMR crystallography by recording the 13C CP/MAS NMR spectra and performing GIPAW NMR calculations with CASTEP. The obtained results revealed the major discrepancies between the calculated and experimental NMR chemical shift values. Those differences were explained at the molecular level, as resulting from the differences in the experimentally determined and DFT‐optimized positions of some atoms, mostly those forming phenyl and thiazole rings. This work is an example of how NMR crystallography can be used to verify and improve the already published crystal structures.
Enhanced Cycling Performance of the LiNiO2 Cathode in Li‐Ion Batteries Enabled by Nb‐Based Surface Coating
Authors: Nascimento Nunes Barbara , Karger Leonhard , Zhang Ruizhuo , Kondrakov Aleksandr , Brezesinski Torsten
Published: November 2024

Lithium nickel oxide (LNO) is a promising cathode candidate in various next‐generation battery technologies. To increase its stability, doping and surface coating have become key strategies. Among various elements, niobium stands out for its dual role as an effective dopant and the advantages of its oxide phases as coatings. In this study, we explore Nb‐based coating of LNO, utilizing methods that minimize or eliminate solvent use. Additionally, the coated samples were treated at two different temperatures to study their effect on properties and electrochemical performance. Our results demonstrate that the coating process strongly affects the cell cyclability and further highlight the potential of Nb‐based protective coatings in enhancing LNO as a cathode active material for application in high‐energy‐density Li‐ion batteries.
A Stochastic Model to Predict Seed Dispersal in Linear and Stokes Waves
Authors: Chen Jun , Zeng Yuhong , Ren Junqing , Liu Xiaoguang
Published: November 2024

Plant cultivation is utilized in coastal ecological restoration to cope with shrinking wetlands, and, benefiting from hydrochory, disseminating indigenous plant seeds represents a high‐efficiency strategy. Random displacement model (RDM) is an efficient alternative to simulate seed dispersal progress via wave. Consequently, we investigated the effect of seed properties and wave characteristics on seeds motion in waves by RDM. Errors between the theoretical comprehensive longitudinal diffusion coefficient of the solute and the simulated one by RDM within an acceptable range indicate that the model is applicable for further simulation of particle dispersal in waves. Simulation results demonstrated that seeds with smaller size and density can transport farther in waves; larger wave heights, smaller water depths and longer wavelengths in linear waves and larger relative wave heights and smaller relative water depths in Stokes waves all promote longitudinally seed diffusion. Finally fitting formulas were proposed for the longitudinal propagation position (including mean and variance) of seed dispersal in linear and Stokes waves. Although this work can provide certain scientific guidance for the restoration of coastal vegetation ecology through natural colonization, there is still much work that needs to be conducted to further the research.
Analysis and Interpretation of Thermal Evolution Anomalies in Palaeozoic Source Rocks in the Southwestern Ordos Basin, China
Authors: Lu Tianao , Huang Junping , Zhang Yan , Wang Pan , Xu Yaohui , Su Kaiming
Published: November 2024

The YT3 well in the southern section of the western margin of the Ordos Basin recently accessed oil reservoirs in the Palaeozoic Carboniferous Yanghugou Formation and Ordovician Wulalike Formation that were previously believed to be gas‐producing. However, the region is characterised by extensive faulting and complex geological phenomena. Additionally, the Wulalike Formation exhibits an anomaly: shallow burial depth and high maturity occur in the western region. This study assesses the maturity of source rocks using organic geochemical methods in typical Palaeozoic oil‐bearing strata of the region. PetroMod software simulations are employed to reconstruct the thermal evolution history of selected wells and seismic profiles, elucidating these maturity anomalies. The findings reveal a generally higher thermal maturity in the western part and lower in the eastern part of the study area. The Ro of the Wulalike Formation ranged from 1.08% to 2.03%, while that of the Yanghugou Formation ranged from 0.55% to 0.68%. Prior to the Jurassic, the western strata were buried at a greater depth than the eastern strata. The source rocks of the western Palaeozoic had already produced a significant amount of hydrocarbons, and at this time, the strata exhibited a monoclinic west‐low‐east‐high pattern. Hydrocarbons would have been transported eastward along the stratigraphic gradient and deposited in suitable traps. After the Jurassic, the western part of the study area underwent significant denudation due to the Yanshan Movement and a strong retrograde overturning effect, which resulted in a shallow burial depth and high maturity.
The Genesis and Circulation of Geothermal Water in the Riduo–Cuona Rift, Eastern Tibetan Plateau, Based on Hydrochemistry and Stable Isotopes Geochemistry
Authors: Liu Yunhe , Zhou Xiaocheng , Wang Sheng , Chen Zhe , He Miao , Tian Jiao , Li Ying , Zhu Xiaoyi , Liu Zhipeng , Lu Baolong , Huang Yi
Published: November 2024

Studying initial geothermal fluids and tectonic active zones is crucial for exploiting intermediate high‐temperature geothermal resources. This study aims to investigate the genesis, circulation and environmental implications of geothermal water in the Riduo–Cuona Rift (RCR) of the eastern Tibetan Plateau. By integrating hydrochemical analysis, stable isotope geochemistry (δ2H, δ18O and 87Sr/86Sr), and noble gas isotope characteristics, the research seeks to develop comprehensive geothermal circulation models in the RCR. (M1) The spatial distribution of geothermal waters near the molten magmatic domes indicated 87Sr/86Sr ranges consistent with those of the rock, respectively. The high Ca, Mg ‘hardness’ spring waters were attributed to strata surrounding the dome resulting from the last leaching, as confirmed by the estimated higher hydraulic head, mainly located in ‘immature water.’ (M2) The spatial distribution of geothermal waters corresponding to an orogenic belt revealed HCO3·SO4–Na as the dominant hydrochemical facies in the northern RCR. Research suggests that springs exhibit greater circulation depths and that spring solute SO4 is related to the Gangdise magmatic arc leaching. (M3) However, the active tectonic zone's springs 87Sr/86Sr (0.705763–0.709754) indicated evaporite characteristics. The thermal reservoir temperature in this structural junction zone is the highest (256.75°C–287.03°C). The high trace alkali element concentrations, particularly of B, F and As, exceeded the WHO guideline; the drainage system analysis indicates regional nonnegligible environmental risks in the Gudui. Establishing these models can clarify the relationships between geothermal fluids, tectonic structures and regional faults, providing insights into geothermal resource potential, environmental risks and possible strategies for sustainable resource exploitation in the region.
The risk factors and prognostic impact of different benign pathologic types of background endometrium surrounding endometrial polyps
Authors: Huang Jiezhuang , Li Yuxin , Chen Peiyue , Zhi Zhifu
Published: November 2024

Objective

This retrospective study investigated the prognostic significance and risk factors of benign pathologic types of background endometrium surrounding endometrial polyps (EPs).

Methods

We assessed 206 patients who underwent hysteroscopic polypectomy and background endometrium biopsy. Patients were categorized into four groups based on the pathologic types of background endometrium: normal proliferative endometrium (NPE), polypoid hyperplastic endometrium (PHE), chronic endometritis (CE), and non‐atypical endometrial hyperplasia (NEH). We employed univariable comparisons and multivariable logistic regression analysis to identify risk factors of PHE, CE, and NEH compared to NPE. Abnormal uterine bleeding (AUB) and recurrence of EPs were monitored over a 12‐month postoperative follow‐up period.

Results

Independent risk factors for EPs with a background of CE included a history of genital tract infection (OR = 8.88, 95% CI: 2.95–26.70, P = 0.000), adenomyosis (OR = 13.70, 95% CI: 3.38–55.52, P = 0.000), and hydrosalpinx (OR = 2.23, 95% CI: 1.59–54.09, P = 0.013). Age (OR = 1.18, 95% CI: 1.07–1.30, P = 0.001) and BMI (OR = 1.33, 95% CI: 1.11–1.61, P = 0.003) were significant risk factors for EPs with a background of NEH. Patients with PHE had higher recurrence rates of EPs following 12 months of follow‐up. Moreover, background endometrium types PHE, CE, and NEH were associated with poorer control of AUB.

Conclusion

Our study underscores the importance of examining the histopathologic characteristics of the background endometrium surrounding EPs, as these benign lesions significantly influence the recurrence and symptomatology of EPs.
Edge Intelligence Empowered English Speech Recognition in Portable Devices
Authors: Li Zhongmin , Huang Weiguo , Gu Cui
Published: November 2024

Online education has greatly promoted English learning. However, many learners still meet difficulty in spoken English. With the fast development of computer science and artificial intelligence, especially natural language processing, online education is becoming more and more intelligent which can greatly assist learners to grasp English speaking skill thorough automatically English speech recognition. However, it is still a challenge task to implement English speech recognition in portable devices which has limited computing resources. In order to tackle this issue, this paper proposes to combine edge intelligence with cloud computing for mobile English speech recognition. First, the preprocessing and feature extraction part is deploy in the edge nodes, such as pad or smart phone. Second, a pretrained speech recognition model is deployed in the cloud server to avoid the limits of edge nodes. The features are sent from edge nodes to cloud server, while the pretrained speech model in the cloud server returns the results to edge nodes. The experiments and simulations demonstrate the proposed solution can adapt the edge nodes with limited resources.
Charge‐Coupled Imager for 525‐Line Television
Authors: RODGERS R.L.
Published: November 2024

The operation and performance parameters are described for a CCD image sensor having 512 × 320 elements (163,840 individual storage sites). The device is designed and fabricated for use in the standard 525‐line television system. This solid‐state imager is capable of performance superior to that of camera tubes with regard to signal‐to‐noise ratio, freedom from lag, and absence of microphonics. Additional features include its small size, light weight, low power, and precision image characteristics.
A qualitative study of the experiences of patients with prostate cancer when receiving negative genetic results: “I still don't have a grasp of what it all means”
Authors: Zayhowski Kimberly , Wang Catharine , Nahorniak Mary , Loo Stephanie , Gignac Gretchen , Gunn Christine
Published: November 2024

Germline genetic testing has been increasingly conducted for treatment implications in patients with prostate cancer due to the expansion of testing eligibility. Understanding patients' comprehension of genetic results is crucial for establishing effective result disclosure practices. This importance has grown due to the increasing prevalence of negative genetic results being conveyed via electronic communication and by providers without a genetics specialization. This study explores patients with prostate cancer's perceptions of genetic results communication. We analyzed 24 qualitative, semi‐structured interviews with patients with prostate cancer at an urban safety‐net hospital who had genetic results documented in their medical records. Interview questions focused on patient experiences with genetic referrals, genetic counseling, and genetic result disclosure. Audio recordings were professionally transcribed and analyzed by the study team utilizing an inductive thematic approach to generate themes from recurring codes. Of those who participated, 18 were interviewed in English, 5 in Spanish, and 1 in Haitian Creole. No participants reported having a pathogenic variant identified with genetic testing. Study participants identified a number of gaps in results communication which led to misconceptions regarding hereditary cancer risk. Three themes were generated: (1) Patients desired clear communication about the next steps after genetic testing, (2) Patients commonly experienced cognitive dissonance with negative genetic results given personal and family history of cancer, and (3) Patients felt reassurance from negative genetic results. This research suggests that maintaining conversations between patients and healthcare providers alongside the delivery of negative results assists in patient comprehension. Additionally, it is essential to evaluate the accessibility and appropriateness of notes and results sent to patients. Ultimately, understanding communication barriers in genetic results return is imperative in order to provide high‐quality genetic care.
長期間の呼吸管理および遷延する低血圧から診断に至ったACTH単独欠損症の1例(A case of isolated ACTH deficiency diagnosed after long–term respiratory management and persistent hypotension)
Authors: 慎太郎 古谷 , 治郎 神山 , 亘 多喜 , 大輔 山本 , 昌士 五木田 , 茂正 田口 , 和也 清田
Published: November 2024

ACTH単独欠損症（isolated ACTH deficiency: IAD）はホルモン欠乏により多彩な臨床症状を示す疾患である。今回，自己排痰できないほどの全身の筋力および咳嗽力の低下を来し，人工呼吸器離脱困難を契機にIADの診断に至った1例を経験したので報告する。症例は60歳の男性。食欲不振から体動困難となり，救急搬送された。脱水および急性腎障害の診断で入院となり，入院後，敗血症性ショックやたこつぼ型心筋症を併発して重症化した。気管挿管人工呼吸管理を行った後，人工呼吸器離脱困難が続き，低血圧も遷延した。神経筋疾患や内分泌疾患を疑い，精査し，IADの診断に至った。IADは既知の疾患であるものの，稀な疾患がゆえ，診断に難渋し治療開始が遅延することがある。救急領域では意識障害や気管挿管により病歴聴取が困難となるため，より診断に難渋する。筋力低下や体重減少などはpost intensive care syndrome / ICU–acquired weaknessの症状と類似することから，経時的に診断は困難となるため早期に鑑別に挙げ精査する必要がある。
覚知状況で比較した予期せぬ院内心停止患者の脳機能予後についての調査報告：単施設後ろ向き観察研究(Brain function prognoses of patients having unexpected in–hospital cardiac arrests subdivided according to circumstances of detection: A single–center, retrospective observational study)
Authors: 豊 齋藤 , 貴大 三吉 , 聡 鳥海 , 邦生 金尾 , 清継 田熊
Published: November 2024

【背景と目的】近年の院内心停止の生存率は改善が乏しいとされるが知見は十分でない。予期せぬ院内心停止の実態を明らかにすることを目的とし，どのような状況の院内心停止患者で予後が良いか，その覚知状況ごとの臨床的特徴・予後を調査した。【方法】2013年4月から10年間に川崎市立川崎病院に入院中に予期せぬ心停止となり院内救急対応システムにより心肺蘇生を受けたものを対象とした。心停止を覚知した経緯を評価し4群（病態悪化で対応中に心停止に移行した「対応群」，偶々訪室すると心停止であった「訪室群」，通常診療中に突然心停止となった「突然発症群」，心電図モニターで覚知した「モニター群」）に分け患者背景・転帰等を群間で比較した。【結果】138例が対象。対応群45例（32.6%），訪室群37例（26.8%），突然発症群26例（18.8%），モニター群30例（21.7%）。年齢，性別，除細動や体温管理療法実施率は有意差なし。心静止は訪室群で多く，無脈性電気活動は対応群で，心室細動 / 無脈性心室頻拍はモニター群で多い傾向あり。自己心拍再開率は群間で有意差なし。24時間生存率，30日間生存率は突然発症群とモニター群で高く，30日後脳機能予後は突然発症群とモニター群で良い傾向あり。【結語】モニターで覚知した院内心停止の予後は良好であり，院内急変対策では心電図モニタリングが有用である可能性がある。