bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral properties of ablating meteorite samples for improved meteoroid composition diagnostics
Authors: Matlovič Pavol , Pisarčíková Adriana , Pazderová Veronika , Loehle Stefan , Tóth Juraj , Ferrière Ludovic , Čermák Peter , Leiser David , Vaubaillon Jérémie , Ravichandran Ranjith
Published: August 2024

Emission spectra and diagnostic spectral features of a diverse range of ablated meteorite samples with a known composition are presented. We aim to provide a reference spectral dataset to improve our abilities to classify meteoroid composition types from meteor spectra observations. The data were obtained by ablating meteorite samples in high-enthalpy plasma wind tunnel facilities recreating conditions characteristic of low-speed meteors. Near-UV to visible-range (320–800 nm) emission spectra of 22 diverse meteorites captured by a high-resolution Echelle spectrometer were analyzed to identify the characteristic spectral features of individual meteorite groups. The same dataset captured by a lower-resolution meteor spectrograph was applied to compare the meteorite data with meteor spectra observations. Spectral modeling revealed that the emitting meteorite plasma was characterized by temperatures of 3700–4800 K, similar to the main temperature component of meteors. The studied line intensity variations were found to trace the differences in the original meteorite composition and thus can be used to constrain the individual meteorite classes. We demonstrate that meteorite composition types, including ordinary chondrites, carbonaceous chondrites, various achondrites, stony-iron and iron meteorites, can be spectrally distinguished by measuring relative line intensities of Mg I, Fe I, Na I, Cr I, Mn I, Si I, H I, CN, Ni I, and Li I. Additionally, we confirm the effect of the incomplete evaporation of refractory elements Al, Ti, and Ca, and the presence of minor species Co I, Cu I, and V I.
Straight outta photosphere: Open solar flux without coronal modeling
Authors: Tähtinen Ismo , Asikainen Timo , Mursula Kalevi
Published: August 2024

Context. The open solar flux, that is, the total magnetic flux escaping the Sun, is one of the most important parameters connecting solar activity to the Earth. The open solar flux is commonly estimated from photospheric magnetic field measurements by making model assumptions about the solar corona. However, the question in which way the open solar flux is directly related to the distribution of the photospheric magnetic field is still partly unknown.

Aims. We aim to reconstruct the open solar flux directly from the photospheric magnetic fields without making any assumptions about the corona and without using coronal hole observations, for instance.

Methods. We modified an earlier vector sum method by taking magnetic field polarities into account and applied the method to the synoptic magnetograms of six instruments to determine the open solar flux from solar cycles 21–24.

Results. The modified vector sum method produces a vector of the global solar magnetic field whose magnitude closely matches the open solar flux from the potential field source surface (PFSS) model both by the absolute scale and the overall time evolution for each of the six magnetograms. The latitude of this vector follows the Hale cycle by always pointing toward the dominantly positive-polarity hemisphere, and its longitude coincides with the location of the main coronal holes of the McIntosh Archive. We find multi-year periods during which the longitude of the vector slowly drifts or stays rather stationary in the Carrington frame. These periods are punctuated by times when the longitude moves rapidly in the Carrington frame. By comparing the magnitude of this vector to the open solar flux calculated from the PFSS model with different source surface heights, we find that the best match is produced with a source surface height Rss = 2.4 − 2.5 R⊙.
Solar active region evolution and imminent flaring activity through color-coded visualization of photospheric vector magnetograms
Authors: Kontogiannis I. , Pietrow A. G. M. , Druett M. K. , Dineva E. , Verma M. , Denker C.
Published: August 2024

Context. The emergence of magnetic flux, its transition to complex configurations, and the pre-eruptive state of active regions are probed using photospheric magnetograms.

Aims. Our aim is to pinpoint different evolutionary stages in emerging active regions, explore their differences, and produce parameters that could advance flare prediction using color-coded maps of the photospheric magnetic field.

Methods. The three components of the photospheric magnetic field vector are combined to create color-combined magnetograms (COCOMAGs). From these, the areas occupied by different color hues are extracted, creating appropriate time series (color curves). These COCOMAGs and color curves are used as proxies of the active region evolution and its complexity.

Results. The morphology of COCOMAGs showcases typical features of active regions, such as sunspots, plages, and sheared polarity inversion lines. The color curves represent the area occupied by photospheric magnetic field of different orientation and contain information pertaining to the evolutionary stages of active regions. During emergence, most of the region area is dominated by horizontal or highly inclined magnetic field, which is gradually replaced by more vertical magnetic field. In complex regions, large parts are covered by highly inclined magnetic fields, appearing as abrupt color changes in COCOMAGs. The decay of a region is signified by a domination of vertical magnetic field, indicating a gradual relaxation of the magnetic field configuration. The color curves exhibit a varying degree of correlation with active region complexity. Particularly the red and magenta color curves, which represent strong, purely horizontal magnetic field, are good indicators of future flaring activity.

Conclusions. Color-combined magnetograms facilitate a comprehensive view of the evolution of active regions and their complexity. They offer a framework for the treatment of complex observations and can be used in pattern recognition, feature extraction, and flare-prediction schemes.
Multidimensional quality of life of hypertension patients analysis using structural equation modelling-partial least square
Authors: Sofyan Hizir , Harva Fajar , Afriyan Ilhan , Inayati Rahmi , Kesuma Zurnila Marli
Published: August 2024

Hypertension is one of the non-communicable diseases that continues to experience an increasing prevalence rate. Hypertension in Indonesia has the highest prevalence compared to other non-communicable diseases. The province of Aceh ranks tenth in the highest prevalence of hypertension in Indonesia. The third highest prevalence cases in Aceh Province is in Pidie Regency. This study was conducted to analyze the factors influencing the quality of life of hypertensive patients using the Structural Equation Modeling-Partial Least Square (SEM-PLS) method. The research utilized data from a non-communicable disease survey conducted in Pidie Regency in 2023. The results of this study revealed 4 indicators representing demographic factors, 3 indicators representing activity factors, and 4 indicators representing quality of life. The factors significantly are demographics, physical activity, and medication adherence, with a Q2 value of 0.98, meaning that 98% of the variability can be explained by demographic, physical activity, and medication adherence factors.
Navigating Visual Information: Understanding Audience Perception and Evaluation in Different Data Visualizations
Authors: Ch’ng Joesuan , Looi Sing Yan
Published: August 2024

In the age of Big Data where data literacy is vital across diverse domains, the prevalence of misleading visualization raises significant concerns. Examining the extent of such visualizations is crucial since viewers often lack the ability to choose the form of presentation. This study aims to investigate the impact of intentionally misleading data visualizations on cognitive biases by exploring factors that potentially influence perceptions and evaluations. A factorial experimental design with three factors involving methods of data visualization, audience academic background and the sequence of data presentation is employed. A total of 60 undergraduate students with two different major programmes from a local higher educational institution participated in this experiment. These students were tasked with responding to predesigned questions based on two different sets of infographics addressing the same issues. The findings indicate that both data presentation and analytical background significantly influence audience evaluation. Additionally, the order of data presentation reveals that audience evaluation is influenced by their initial negative impression. These results underscore the critical role of data literacy in enhancing the understanding of visual information, particularly in the context of public issues.
On the sum of an idempotent and a tripotent in a quaternion algebra over the ring of integers modulo p
Authors: Lai Wei Kit , Qua Kiat Tat , Wong Denis Chee Keong
Published: August 2024

Let H be denoted as quaternions. Quaternions form an algebra over a ring R, as an extension of complex numbers into a four dimensional space, where H = {a0 + a1i + a2j + a3k | a0, a1, a2, a3 ∈ R}. A quaternion algebra, particularly defined over fields of characteristic 0, finds numerous applications in physics. In this article, we explore some properties of the sum of an idempotent and a tripotent in the finite ring H/Zp, adapting the definition of SIT rings that was introduced by Ying et al in 2016. We provide some conditions for H/Zp to be SIT rings and we give some examples of weakly tripotent rings (Breaz and Cimpean, 2018) in H/Zp.
Unsteady Dusty MHD Boundary Layer Flow Past A Sphere
Authors: Jefri Nur Najeeha Natasha , Ali Anati
Published: August 2024

The boundary layer problem for unsteady dusty Newtonian fluid flow through a sphere influenced by magnetic field has been investigated in this paper. The two fluid flow phases that will be discussed in this work are referred to as dusty. Including the fluid and dust phases in a two-phase flow can help us comprehend the interaction of dust particles in fluid flow better. Next, the impact of magnetohydrodynamics (MHD) on fluid flow will be important to researchers since it allows them to regulate systems like cooling systems by adjusting the magnetic field. Thus, by considering the influenced of magnetic field and the existence of dust particles will be examined in this paper. The mathematical model for fluid and dusty phases is developed using continuity and momentum equations. First order partial differential equations (PDEs) are obtained by applying suitable similarity transformations on higher order PDEs The Finite Difference Method (FDM), Newton's method, and the development of a block tridiagonal matrix are the main rules that are solved using the Keller Box method. The Keller Box procedure is programmed in MATLAB environment and analysed graphically. The results are discovered to be quite compatible with earlier research.
Investigating accuracy of biomarker involving a parametric approach of proportional hazard skewed normal model
Authors: Mohd Azhar Ahmad Faiz , Kamarudin Adina Najwa
Published: August 2024

Time-dependent receiver operating characteristic (ROC) curve is useful to measure the accuracy performance over time. In this paper, we have shown how to determine the accuracy trend using proportional hazard model with continuous skewed normal biomarker and skewed normal time-to-event. Bayesian inference and adaptive multivariate integration over hypercubes are used respectively for parameter estimation and solving the sensitivity and specificity of the time-dependent ROC. The simulation study and application on real data suggest that it is possible to predict the accuracy measurement over time by changing the estimated association parameter between the biomarker and time-to-event data. In addition, studies on the impact of sample size on the ROC curve shows an advantage of this parametric method over conventional nonparametric.
Comparison of support vector machine and random forest algorithms for classification of songs for relaxation purposes in individuals with stress disorders
Authors: Khamngam Anusara , Srisodaphol Wuttichai , Junsawang Prem
Published: August 2024

The research compares the performance of support vector machine (SVM) and random forest algorithms in identifying songs suitable for relaxation in patients with stress problems. The dataset comprises both Thai and international songs categorized into therapy and non-therapy groups. The results demonstrate that the support vector machine achieves an accuracy of 78%, outperforming the random forest with an accuracy of 72%. Precision and F1-score metrics further emphasize the superiority of the support vector machine in classification. Notably, the support vector machine has recall rates of 50% and 100% for therapy and non-therapy classes, respectively, while the random forest has recall from class therapy of 38% and class non-therapy of 100%. The findings suggest that providing individuals with stress issues the opportunity to listen to stress-reducing music can be a viable approach to reducing the need for psychiatric therapy. The support vector machine is a better algorithm than the random forest for classifying songs for relaxation because it is more accurate, precise, and has more even recall rates.
Universal portfolio generated by Hellinger distance
Authors: Chia Xin Ying , Kuang Kee Seng , Lee Hui Shan , Phoon Sheong Wei , Tan Choon Peng
Published: August 2024

There are numerous universal portfolios generated in different studies using various divergence functions to achieve one goal, which is to maximize wealth. To extend the exploration, through this study, we have generated a new universal portfolio using the Hellinger distance. We conducted a comprehensive performance evaluation of our newly developed universal portfolio against common strategies such as the buy-and-hold strategy and the constant rebalanced portfolio. This evaluation used diverse stock price data from the Bursa Malaysia local platform for trading stocks, bonds, and other securities. Our empirical findings demonstrate that the Hellinger distance-based universal portfolio outperformed the traditional strategies in two out of three datasets over a period of 535 trading days. Specifically, the Hellinger portfolio shows a significant improvement in wealth accumulation, with data set X achieving the highest wealth increase and exhibiting nearly 99% allocation to the most profitable stock. These results highlight the potential of the Hellinger distance-based approach in improving the performance of universal portfolios and offer a promising tool for investment decision-making in today’s complex and unpredictable financial markets.
Examinations of viscous dissipation, magnetic field and thermal radiation on the systematic flow of Casson fluid with gyrotactic microorganisms
Authors: Usman Abubakar
Published: August 2024

This research work is aimed at examining the significance of viscous dissipation, magnetic field alongside thermal radiation on the flow of Casson fluid. The fluid flow was considered in the presence of gyrotactic microorganisms and nanoparticles. The physics of the problem is governed with partial differential equations (PDEs). The set of PDEs are changed to ordinary differential equations (ODEs) by utilizing an appropriate similarity variables. To examine the pertinent flow parameters, a numerical approach called spectral relaxation method (SRM) was employed. This SRM approach employs the basic Gauss-seidel method to decouple and descritize the set of differential equations. The choice of this approach is due to its consistency and accuracy. The viscous dissipation parameter (Ec) was found to enhance fluid temperature, velocity and boundary layers (thermal and momentum boundary layer). The strong opposition of magnetic parameter give rise to lorenz force which drags the fluid flow within the boundary layer. The nanoparticles was found to bare great effect on the gyrotactic microorganisms.
Analysis of socio-economic factors affecting coastal community preparedness using structural equation modeling
Authors: Sofyan Hizir , Rolanda Randy , Hidayati Alfy , Syamsidik  , Oktari Rina Suryani
Published: August 2024

Preparedness refers to the actions taken before a disaster to ensure an effective response. In disaster-related research, quantitative studies typically focus on observing direct correlations and regressions. However, directly measuring preparedness can be challenging. To comprehensively analyze variables, researchers often turn to Structural Equation Modeling (SEM), a powerful alternative. SEM is particularly useful when examining complex relationships among multiple variables. In a study focused on coastal communities in the cities of Banda Aceh, Mataram, and Ambon, the SEM method was applied using secondary data. The research considered one endogenous latent variable called “preparedness” and two exogenous latent variables related to social and economic factors, which are involving a collective of 932 participants. The results from the SEM method using GOFI criteria indicated that socio-economic factors significantly influenced coastal community readiness, with an R-squared value of 56.5%.
As real as possible: Chancen und Herausforderungen von Online-Psychotherapie
Authors: Andreas Sylke
Published: August 2024

Im Zuge der fortschreitenden Digitalisierung und moderner Technologien gewinnen videobasierte Psychotherapien immer mehr an Bedeutung. Sie haben einige Vorteile, bergen aber auch Herausforderungen. Gerade innerhalb der psychoanalytischen Gemeinschaft werden sie kritisch diskutiert. Dieser Beitrag zeigt anhand von zwei empirischen Studien, wie ähnlich videobasierte Settings dem Realkontakt kommen können.
Methoden der Geburtsüberwachung bei der Stute – eine
Übersicht
Authors: Lindinger Hannah , Wehrend Axel
Published: August 2024

Zur Geburtsüberwachung beim Pferd stehen verschiedene Systeme zur Verfügung.
Dabei muss zwischen den Methoden zur genaueren Vorhersage des Geburtstermins, um
zeitnah die Überwachung der Stute zu intensivieren, und den Methoden, um Tiere
in der Geburt zu detektieren, unterschieden werden. Grundsätzlich ist
festzustellen, dass fast keine Untersuchungen, die verschiedene Methoden an
einer gleichen Population von Stuten vergleichend testen, vorliegen. Mit
Annäherung an den Geburtszeitpunkt verändern sich physiologische Parameter von
Stute und Fetus, deren Variabilität jedoch zu hoch ist, um den exakten
Geburtszeitpunkt prospektiv vorauszusagen. Die derzeit beste Methode ist der
Nachweis des Absinkens des pH-Wertes und der Anstieg der Kalziumkonzentration im
Eutersekret.

Zur Detektion der Geburt ist zum jetzigen Zeitpunkt die durchgängige
Kameraüberwachung die Methode der Wahl. Nachteilig ist, dass die Aufnahmen von
einem Menschen bewertet werden müssen. Neuere Entwicklungen durch den Einsatz
der künstlichen Intelligenz könnten hier Entlastung schaffen. Bevor diese
Methoden praxisreif sind, ist die Kombination von Kameraüberwachung und einem
Sensor, der in die Vulva eingenäht und in der Öffnungsphase der Geburt aktiviert
wird, die sicherste Methode.
Mykotoxinvergiftung nach Walnussaufnahme bei 54
Hunden
Authors: Braun Vanessa , Kanstinger Alina , Dahlem Dorothee
Published: August 2024

Gegenstand und Ziel Ziel dieser retrospektiven Studie ist die Beschreibung
der Intoxikation mit tremorgenen Mykotoxinen nach Walnussaufnahme bei einer
großen Hundepopulation und die Evaluierung der Entwicklung der klinischen
Symptomatik unter der initiierten Therapie.

Material und Methoden Vierundfünfzig Hunde wurden in die Studie
eingeschlossen, die vornehmlich mit Tremor, Hyperästhesie, Hyperthermie und
Ataxie innerhalb weniger Stunden nach beobachteter oraler Aufnahme von Walnüssen
oder begründetem Verdacht vorstellig wurden.

Ergebnisse Vornehmlich wurden die Patienten im Winter und Frühling
vorstellig. Dreiundfünfzig der 54 Hunde wurden zur symptomatischen sowie
dekontaminierenden und eliminierenden Therapie stationär aufgenommen (98%). Zur
symptomatischen Therapie kamen bei 14 Hunden eine antikonvulsive Therapie (26%)
sowie bei der Hälfte der Patienten eine antiemetische Therapie (n=27; 50%) zum
Einsatz. Eine forcierte Emesis zur Dekontamination wurde aufgrund des
Schweregrads der neurologischen Symptome lediglich bei 6 Patienten eingeleitet
(11%). Als weitere dekontaminierende Maßnahme erfolgte eine orale Gabe von
Aktivkohle nach Besserung der klinischen Symptome (n=39; 72%). Die Mehrzahl der
Hunde (n=45; 83%) erhielt eine intravenöse Lipidtherapie zur Elimination sowie
isotone kristalloide Infusionslösung zum Ausgleich von Flüssigkeitsverlusten.
Nebenwirkungen nach intravenöser Lipidtherapie wurden nicht beobachtet. Der
Großteil der Patienten verblieb 2 Tage stationär (n=44; 81%). Bei der Mehrzahl
der Patienten war die klinische Untersuchung am Tag der Entlassung unauffällig
(n=39; 72%). Potenzielle Folgeschäden nach Mykotoxinvergiftung wurden bei keinem
der Patienten im weiteren Verlauf dokumentiert.

Schlussfolgerung Aufgrund der Lipophilie von Mykotoxinen kann der Einsatz
einer intravenösen Lipidtherapie zur Toxinelimination in Erwägung gezogen
werden. Die Prognose bei Mykotoxinvergiftung nach Walnussaufnahme nach
dekontaminierenden und eliminierenden Maßnahmen ist gut.

Klinische Relevanz Bei unspezifischen neurologischen Symptomen wie Tremor,
Ataxie und Hyperästhesie sowie entsprechendem Vorbericht sollte eine
Intoxikation mit Mykotoxin behafteten Walnüssen in Betracht gezogen werden.
Dermatologie zwischen Kälteschäden, Gonorrhö und „Rassenpolitik“
Authors: Friedmann Ina
Published: August 2024

Ziel der Studie Die Auseinandersetzung mit der Karriere des kommissarischen Leiters der Innsbrucker Hautklinik im Nationalsozialismus, Hans Loos, stellt einen Beitrag zur Geschichte der Klinik sowie auch der Disziplin allgemein dar.

Methodik Auf Basis von Archivalien, zeitgenössischen Publikationen und den Personal- und Vorlesungsverzeichnissen der Universität Innsbruck werden die akademische Karriere, Werk und Wirken von Loos sowie die Verbindung von (medizinischer) Wissenschaft und NS-politischen Ideologien exemplarisch untersucht.

Ergebnisse Hans Loos war weder führender noch exponierter, allerdings überzeugter Nationalsozialist. Mit seinem Spezialgebiet der Kälteschäden bewegte er sich auf „kriegswichtigem“ Terrain und seine Aktivität im Bereich der „Rassenpolitik“ verstand er vereinzelt auch fachspezifisch sowie -übergreifend darzulegen.

Schlussfolgerung Weitere Forschungen zu Loos, insbesondere hinsichtlich seiner Teilnahme an der Tagung über Ärztliche Fragen bei Seenot und Winternot am 26. und 27. Oktober 1942 in Nürnberg, sind unerlässlich und versprechen zusätzliche Erkenntnisse.
Einfluss der Hypothyreose auf die Fruchtbarkeit bei der Hündin und
die neonatale Mortalität und Morbidität – eine
Literaturübersicht
Authors: Egger Rebecca , Conze Theresa , Wehrend Axel
Published: August 2024

Es existieren einige Studien und Einzelfallberichte, welche eine Verbindung
zwischen einer Hypothyreose und Reproduktionsstörungen bei der Hündin und einer
erhöhten neonatalen Mortalität und Morbidität bei Welpen postulieren. Andere
Arbeiten wiederum können einen Zusammenhang im Hinblick auf eine Verbindung
zwischen einer Hypothyreose und Reproduktionsstörungen bei der Hündin nicht
nachweisen. In dieser Arbeit soll die entsprechende Literatur auf ihre Evidenz
überprüft werden. Anhand einer Literaturauswertung wird der Zusammenhang
zwischen Hypothyreose und Reproduktionsstörungen der Hündin, Welpensterblichkeit
und neonataler Morbidität, analysiert. Dazu wurde die zur Verfügung stehende
deutsche und internationale „englischsprachige“ Literatur von 1986 bis Januar
2023 analysiert. Es zeigt sich, dass nur wenig Literatur hohe wissenschaftliche
Evidenz aufweist, da es sich zumeist um Fallberichte und Expertenmeinungen
handelt. In einigen Einzelfallberichten konnte zwar ein Zusammenhang zwischen
Zyklusunregelmäßigkeiten, Galaktorrhö und Infertilität und dem Vorliegen einer
Hypothyreose gesehen werden; in experimentellen Untersuchungen und nach Meinung
anderer Autoren ist der Zusammenhang zwischen Hypothyreose und
Reproduktionsstörungen jedoch nicht vorhanden. Auch ein negativer Einfluss der
Hypothyreose auf den Geburtsablauf konnte nicht eindeutig belegt werden. In
einer experimentellen Studie waren zwar die Dauer und die Intensität der
Uteruskontraktionen bei Tieren mit Hypothyreose länger und schwächer, jedoch war
das Intervall zwischen der Geburt von Welpen nicht beeinträchtigt. Lediglich im
Bereich der neonatalen Mortalität sowie Morbidität ließ sich ein Zusammenhang
mit der Hypothyreose des Muttertieres aufzeigen. Die Welpen betroffener
Hündinnen zeigten ein geringeres Geburtsgewicht und waren lebensschwächer als
Welpen von euthyreoten Hündinnen. Die Bedeutung einer Schilddrüsenunterfunktion
für die Fruchtbarkeit bei der Hündin ist in der Literatur noch nicht belegt.
Diese Endokrinopathie scheint aber Einfluss auf die neonatale Vitalität zu
haben.
Hypervalent-Iodine-Mediated Base-Free Oxidative Olefination of Benzylic Amines to Access α,β-Unsaturated Ketones
Authors: Suryavanshi Gurunath , Rupanawar Bapurao D. , Bansode Ajay H.
Published: August 2024

We report a one-pot base-free protocol for the oxidative olefination of benzylic amines promoted by a hypervalent iodine reagent for the synthesis of α,β-unsaturated ketones. Mechanistically, (diacetoxyiodo)benzene oxidizes the benzylic amine to the corresponding imine, which, on reaction with a phenacyl(triphenyl)phosphonium bromide salt and an in situ generated acetoxy anion leads to an α,β-unsaturated ketone. A wide range of α,β-unsaturated ketones were easily accessed through direct oxidative olefination of substituted benzylic amines in good to excellent yields and with high E-selectivity.
Combined Extracorporeal Shock Wave Lithotripsy and Endoscopic Retrograde Pancreatography for Painful Chronic Pancreatitis: Is It Effective?
Authors: Telaprolu Harshavardhan , Rana Surinder Singh
Published: August 2024

Management of pain in chronic pancreatitis (CP) is challenging, and surgery used to be the intervention of choice in patients having pain refractory to medical therapy. Advancement in minimally invasive interventions resulted in a paradigm shift in the management of pain in CP. Pancreatic endotherapy is currently considered the intervention of choice for the management of ductal hypertension in CP. However, multiple mechanisms including ductal hypertension and neurogenic as well as psychological factors contribute to the causation of pain in CP and therefore no single intervention is effective in all patients. The precise role of interventional procedure in a complex disease like CP with multiple pathogenic mechanisms requires a prospective comparative study with a sham group and there are no such comparative studies in the literature. In this news and views, we discuss a recently published sham-controlled randomized trial (Combined extracorporeal shock wave lithotripsy and endoscopic treatment for pain in chronic pancreatitis (SCHOKE) trial) that examined the efficacy of extracorporeal shock wave lithotripsy (ESWL) and endoscopic retrograde pancreatography (ERP) compared with the sham procedure.
16S rRNA Sequencing Reveals Alterations of Gut Bacteria in Hirschsprung-Associated Enterocolitis
Authors: Shi Hao , She Yong , Mao Wu , Xiang Yi , Xu Lu , Yin Sanjun , Zhao Qi
Published: August 2024

Hirschsprung-associated enterocolitis (HAEC) stands as most common and serious complication of Hirschsprung's disease. Variations in the microbiota composition may account for the differences observed between HAEC and healthy individuals, offering crucial insights into the disease's pathogenesis. Here, we performed a study to changes in the gut microbiome using 16sRNA amplicon sequencing in a cohort of HAEC patients (n = 16) and healthy controls (n = 14). Our result revealed a significant disparity in beta diversity between the two groups. Following correction for false discovery rate, a rank–sum test at the genus level indicated a notable decrease in the relative abundance of Bifidobacterium, Lactobacillus, and Veillonella, whereas the Enterococcus genus exhibited a substantial increase in HAEC, a finding further supported by additional linear discriminant analysis effect size analysis. Functional analysis showed that putative transport and catabolism, digestive system, and metabolism of cofactors and vitamins were proved to be some abundant KOs (Kyoto Encyclopedia of Genes and Genomes [KEGG] orthologs) in healthy group, whereas infectious disease, membrane transport, and carbohydrate metabolism were the three KOs with the higher abundance in the HAEC group. Our data increased our insight into the HAEC, which may shed further light on HAEC pathogenesis. Our study firstly demonstrated the difference between fecal microbiota of HAEC patients and healthy individuals, which made a step forward in the understanding of the pathophysiology of HAEC.
In situ measurement of spectral linewidth in wavelength-modulated signals for frequency-modulated continuous-wave LiDAR systems
Authors: La Jongpil , Han Munhyun , Choi Jieun , Mheen Bongki
Published: August 2024

This paper advances an in situ method to measure the spectral linewidth directly from the currently generated wavelength-modulated signals in frequency-modulated continuous-wave (FMCW) light detection and ranging (LiDAR) systems, diverging from traditional methods that focus on the linewidth of the original unmodulated laser source. Our approach, employing a self-heterodyne technique with a short-delay line, specifically targets the modulated signal’s linewidth in real-time, which is vital for the operational fidelity of FMCW LiDAR systems. Crucially, our method leverages the unique capabilities of an optical hybrid for accurate phase noise and linewidth measurements, distinguishing it from conventional beat frequency extraction techniques. For the evaluation of the spectral linewidth measurement, a frequency-modulated laser source based on an optical phase-locked loop configuration was first described where the laser achieves linear optical frequency modulation by controlling the injection current of an external cavity diode laser (ECDL). The phase error measured from a Mach–Zehnder interferometer signal is used to detect the frequency deviation error from the target value, which is then fed back to the driving current of the ECDL to compensate it. Utilizing the proposed method, the laser’s linewidth for the fabricated FMCW LiDAR was measured to be 287 kHz, exhibiting a clear Lorentzian spectrum shape, where the spectral modulation bandwidth and sweep time were 2.91 GHz and 50 µs, respectively. The results clearly demonstrate that the proposed in situ spectral linewidth measurement provides an efficient method for performance monitoring of FMCW LiDAR.
Sim2Real in reconstructive spectroscopy: Deep learning with augmented device-informed data simulation
Authors: Chen Jiyi , Li Pengyu , Wang Yutong , Ku Pei-Cheng , Qu Qing
Published: August 2024

This work proposes a deep learning (DL)-based framework, namely Sim2Real, for spectral signal reconstruction in reconstructive spectroscopy, focusing on efficient data sampling and fast inference time. The work focuses on the challenge of reconstructing real-world spectral signals in an extreme setting where only device-informed simulated data are available for training. Such device-informed simulated data are much easier to collect than real-world data but exhibit large distribution shifts from their real-world counterparts. To leverage such simulated data effectively, a hierarchical data augmentation strategy is introduced to mitigate the adverse effects of this domain shift, and a corresponding neural network for the spectral signal reconstruction with our augmented data is designed. Experiments using a real dataset measured from our spectrometer device demonstrate that Sim2Real achieves significant speed-up during the inference while attaining on-par performance with the state-of-the-art optimization-based methods.
Kinetic inductance compact resonator with NbTiN micronwires
Authors: Yang Ming , He XiaoLiang , Gao WanPeng , Chen JunFeng , Wu Yu , Wang XiaoNi , Mu Gang , Peng Wei , Lin ZhiRong
Published: August 2024

Nonlinear resonators of superconducting thin-film kinetic inductance have attracted considerable research interest in the fields of detectors, qubits, parametric amplifiers, and more. By tuning the deposition parameters, niobium titanium nitride (NbTiN) films (∼12 nm in thickness) present high resistivity(∼2000 μΩ cm) and large sheet kinetic inductance (∼0.7 nH/□). We designed resonators with NbTiN micronwire as the inductor and aluminum as the capacitor, which result in a high internal quality factor and a Kerr nonlinearity of a few hertz. The radio frequency response of the resonators demonstrates nonlinear behavior similar to that of the cubic Duffing oscillator, including frequency shift and hysteresis region. The kinetic inductance resonator is a promising candidate for high saturation power parametric amplifiers.
Design of a high-precision time-to-digital converter in an Elitestek Ti60 field-programmable-gate-array
Authors: He Zongwu , Wen Xincheng , Wang Jian , Ma Qingli , Yin Zejie
Published: August 2024

The time-to-digital converter (TDC) implemented in a field-programmable-gate-array has garnered widespread attention due to its flexibility and high-performance capabilities. However, issues such as non-uniformity, the bubble in the tapped delay line, and the presence of certain ultra-wide delay units can significantly compromise the precision and nonlinearity of the TDC. In this paper, we propose a high-precision TDC in an Elitestek Ti60 FPGA, effectively eliminating the adverse effects of non-uniformity, the bubble, and certain ultra-wide delay units. The TDC is constructed with a 318-stage delay chain and operates at a low system clock frequency of 150 MHz. The least significant bit (LSB) of the TDC is 21.92 ps. The differential nonlinearity (DNL) is between (−0.976, 1.615) LSB and the integral nonlinearity (INL) is between (−1.446, 2.678) LSB. The TDC achieves a root-mean-square error of 14.783 ps when utilized for measuring various time intervals.
Effect of thickness on optical properties of InSe/In2Se3 heterojunction
Authors: Wang Zijian , Wang Meng , Nan Haiyan , Bai Jing , Wang Chenglin
Published: August 2024

This study focuses on exploring the optical and electrical properties of indium selenide/indium diselenide heterojunctions of varying thicknesses. High-quality thin-layer samples of indium selenide and indium diselenide were prepared using a mechanical exfoliation method. Characterization of these heterojunctions through Raman spectroscopy and fluorescence spectroscopy revealed the significant influence of the layer thickness on the electron transfer mechanisms between the materials. The application direction was determined from the output characteristic curves and photocurrent effects. The experimental results emphasize the controllability of electron transfer and underscored the importance of material thickness in optimizing the design of optoelectronic devices, highlighting the advantages of this heterojunction device for weak light detection. In particular, it was found that heterojunctions with different contrasts can be divided into two states based on their photoluminescence (PL) intensity. For example, in the indium selenide (InSe)/indium diselenide (In2Se3) heterojunction with R = 0.075, the PL intensity of InSe was ∼14 000, whereas that of In2Se3 was ∼900. The fluorescence intensity of the heterojunction before transfer was ∼5000, showing a decreasing trend after transfer. In contrast, for the heterojunction with R = 0.475, the PL intensity of InSe is ∼11 000 and that of In2Se3 is ∼9000, with the PL intensity of the heterojunction increasing to ∼18 000. In addition, at Vds > 0.5, the device formed a junction. This study provides valuable insights into enhancing the heterojunction performance and offers a new perspective in the field of optoelectronic devices.
Quantum-tunneling deep neural network for optical illusion recognition
Authors: Maksymov Ivan S.
Published: August 2024

The discovery of the quantum tunneling (QT) effect—the transmission of particles through a high potential barrier—was one of the most impressive achievements of quantum mechanics made in the 1920s. Responding to the contemporary challenges, I introduce a deep neural network (DNN) architecture that processes information using the effect of QT. I demonstrate the ability of QT-DNN to recognize optical illusions like a human. Tasking QT-DNN to simulate human perception of the Necker cube and Rubin’s vase, I provide arguments in favor of the superiority of QT-based activation functions over the activation functions optimized for modern applications in machine vision, also showing that, at the fundamental level, QT-DNN is closely related to biology-inspired DNNs and models based on the principles of quantum information processing.
Measurement of the thermal accommodation coefficient of helium on a crystalline silicon surface at low-temperatures
Authors: Franke Alexander , Sültmann Nils , Reinhardt Christoph , Croatto Sandy , Schaffran Jörn , Masalehdan Hossein , Lindner Axel , Schnabel Roman
Published: August 2024

Proposals for next-generation gravitational wave observatories include cryogenically cooled 200 kg test mass mirrors suspended from pendulums and made of a crystalline material such as crystalline silicon. During operation of the observatories, these mirrors undergo heating due to the absorption of laser radiation of up to a watt. Low noise cooling techniques need to be developed. Low-pressure helium exchange gas at 5 K might contribute to the challenging task. Here, we report the measurement of the helium accommodation coefficient

α
(
11

K

<
T
<
30

K

)

, which is the probability that a helium atom thermalises with a surface at a given temperature when reflected from it. We find

α
(
T
)
>
0.7

for temperatures

<

20

 K, which increases the cooling power compared to recently used assumptions. The idea of free molecular flow helium gas cooling is thus supported and might find application in some observatory concepts.
A note on Weyl gauge symmetry in gravity
Authors: Mohammedi N
Published: August 2024

A scale invariant theory of gravity, containing at most two derivatives, requires, in addition to the Riemannian metric, a scalar field and (or) a gauge field. The gauge field is usually used to construct the affine connection of Weyl geometry. In this note, we incorporate both the gauge field and the scalar field to build a generalised scale invariant Weyl affine connection. The Ricci tensor and the Ricci scalar made out of this generalised Weyl affine connection contain, naturally, kinetic terms for the scalar field and the gauge field. This provides a geometric interpretation for these terms. It is also shown that scale invariance in the presence of a cosmological constant and mass terms is not completely lost. It becomes a duality transformation relating various fields.
A high-performance microwave plasma source employing dielectric wedges
Authors: Yang Fengming , Zhang Wencong , Huang Kama , Yang Yang , Zhu Huacheng
Published: August 2024

The microwave-to-plasma energy conversion efficiency and the ease of plasma self-ignition are critical factors affecting the applications for microwave plasma sources (MPSs). This study presents a novel MPS utilizing dielectric wedges for self-ignition and improved energy conversion. Firstly, we crafted a dielectric wedge with a gradient refractive index, guiding the electric field from air to dielectric materials and facilitating microwave propagation along the dielectric in a waveguide. Through electromagnetic simulation, we explored how the size and permittivity of the dielectric wedge affect the electric field distribution. Then, the MPS based on the dielectric wedge was designed. In this configuration, a dielectric tube encloses the discharge tube, connecting to dielectric wedges to guide electromagnetic waves to the plasma. We analyzed the MPS performance using the Drude model, evaluating microwave energy conversion efficiency across various electron densities and collision frequencies. The results were compared with a commonly used MPS based on a tapered waveguide, demonstrating the proposed MPS has wider applicability across different operation conditions. Finally, experiments under low pressures were conducted using various gases, showing an average energy conversion efficiency of approximately 40% higher than the tapered waveguide MPS. The experiments also indicate the proposed MPS has a greater capability of self-ignition at lower power levels. These findings highlight the efficacy of incorporating dielectric wedges to enhance MPS performance, making it conducive for broader industrial applications.
In-situ and ex-situ characterizations of PVT-grown 4H-SiC single crystals
Authors: Shao Qinqin , Shen Ruohan , Tian He , Pi Xiaodong , Yang Deren , Wang Rong
Published: August 2024

4H silicon carbide (4H-SiC) is one of the most promising candidates in high-power and high-frequency devices, owing to its excellent properties such as wide bandgap, high electron mobility, high electric breakdown field and high thermal conductivity. The physical-vapor-transport (PVT) approach has been broadly adopted to grow 4H-SiC single-crystal boules. Because of the high-temperature growth of 4H-SiC single-crystal boules, the PVT system is a ‘black-box’ system, which decreases the yield and thus increases the cost of 4H-SiC single-crystals. Although advanced modern characterization tools, e.g. atomic force microscopy, x-ray topography, x-ray diffraction and Raman scattering spectroscopy, can provide deep insight into the structural and defect properties of 4H-SiC boules, it is rather limited to gain in-situ information of the growth process by these ex-situ methods. Therefore, the in-situ visualization on the evolution of structural morphologies and defects conducted by x-ray computed tomography (xCT) is of great importance for further development. In this topical review, the application of the xCT technology on the in-situ visualization of the evolution of the growth front, growth rate, defects, and the mass transport of the source material of 4H-SiC are reviewed. The ex-situ characterization of 4H-SiC single-crystal boules are also briefly introduced. This topical review provides insight into the growth process, structural morphology, and defect evolution of PVT-grown 4H-SiC single-crystal boules.
Large-area gapped edge states in a valley photonic crystal heterostructure
Authors: Li Meize , Liu Yahong , Zhou Xin , Du Lianlian , Li Peng , Tao Liyun , Song Kun , Li Zhenfei , Zhao Xiaopeng
Published: August 2024

Recent works exploiting photonic valley Hall effect show that large-area topological states can be realized by inserting gapless photonic crystal structures into topological interfaces, thus effectively introducing mode width degree of freedom. However, the previously reported works focus on gapless edge states. It is rare to investigate gapped edge states, especially large-area gapped edge states. In this paper, large-area gapped edge states in a valley photonic crystal heterostructure are achieved and experimentally proved. Compared with large-area gapless topological states, the present gapped edge states are more localized, which provides a more effective way to manipulate electromagnetic waves. We implement a topological energy concentrator and topological resonator cavity based on the large-area topological transmission with the gapped edge states. It is expected that our results broaden photonic systems, which can be used in topological lasing, field enhancement, and high-capacity energy transport.
Photochromic webbing structures for monitoring UV-induced mechanical strength degradation
Authors: Kazemipour Sina , John Ohanian III Osgar , Porfiri Maurizio , Zhang Peng
Published: August 2024

Webbing structures are critical load-bearing components in a wide array of applications from structural restraint layers in inflatable space habitats to safety harness belts used by construction workers. In the field, webbings are subjected to ultraviolet (UV) irradiation from sunlight, leading to material degradation and a loss of mechanical strength. To date, health monitoring of webbings has relied on empirically correlating UV-induced strength loss with variations in their inherent color, which often yields inconsistent and imprecise results. To fill this gap, we propose a novel class of photochromic webbing structures that afford noninvasive monitoring of UV-induced degradation of their mechanical strength. The webbings’ sensing capabilities are achieved by integrating a class of photochromic yarns, fabricated through a pressurized coating process. Under continuous UV irradiation, the proposed photochromic webbings exhibit a substantial color change, demonstrating a sensing lifetime equivalent to several months in field conditions. We establish a strong correlation between the webbings’ photochromic response and their strength loss, supporting the feasibility of the proposed webbings in monitoring their mechanical integrity. To elucidate the sensing mechanism, we propose a physics-based mathematical model that describes the underlying photochemical reactions. Through an asymptotic analysis, we demonstrate that the model accurately predicts the webbing’s long-term photochromic responses under extended UV irradiation. The proposed photochromic webbing structures and the predictive mathematical model could enhance the safety and integrity of webbing-based engineering systems.
Multi-objective topology optimization of macro structure and microtubule network structure for self-healing material
Authors: Tan Jianbin , Li Peng , Cheng Wentao , Zhang Changyou , Fan Baijia , Wang Shenbiao , Zhan Jinqing
Published: August 2024

Self-healing materials possess the capability to promptly repair minor damages occurring during service, thereby effectively preventing safety accidents. This paper investigates a multi-objective topology optimization method for the macro structure and microtubule network of self-healing materials around pure epoxy resin materials, aiming to enhance the damage healing capability of the microtubule network while meeting the mechanical performance requirements of the macro structure. By introducing the design variables of macro structure and microtubule network, the corresponding topological description functions are established respectively. And study applies logical operations and post-processing techniques to generate an embedded microtubule network structure description. The objective functions include the flexibility of the macro structure, the along-travel head loss, and the total length of the microtubule network, with material volume serving as a constraint. In order to determine the head loss of the three-dimensional microtubule network structure, a Hardy-Cross method based on flow initialization and loop search is proposed. Multi-objective topology optimization is designed based on moving morphable components algorithm, enumeration method and Pareto principle. Develop iterative termination conditions by assessing the disparity between Pareto solution sets in each generation, thereby ensuring algorithm convergence. The numerical example of the Messerschmitt–Bölkow–Blohm (MBB) beamyields a flexibility of 0.059 without a carrier and 0.0728 with a carrier the macrostructural flexibility without a carrier is 81.0% compared to with a carrier, and the macrostructural profiles and the overall flexibility of the MBB beams with/without a carrier are close to each other. This method serves as a reference for optimizing large-scale self-healing structures.