bluuebunny/crossref_metadata_2025 huggingface dataset:
Gesundheitskompetenz, Anlaufstellen, ungedeckte subjektive Bedarfe und
Behandlungszufriedenheit von Long-COVID-Betroffenen mit langanhaltender
neuropsychiatrischer Symptomatik
Authors: Jung Franziska , Zülke Andrea , Wirkner Kerstin , Reusche Matthias , Engel Christoph , Sander Christian , Witte Veronica , Zeynalova Samira , Loeffler Markus , Villringer Arno , Saur Dorothee , Schomerus Georg , Luppa Melanie , Riedel-Heller Steffi G.
Published: July 2024

Ziel der Studie Ziel der Studie war die Untersuchung der Gesundheitskompetenz
(GK) sowie verschiedener Versorgungsaspekte von Long-COVID-Betroffenen.

Methodik Daher wurden 407 Long-COVID Betroffene mit langanhaltender
neuropsychiatrischer Symptomatik im LIFE-Studienzentrum befragt. Mittels
deskriptiver, sowie Regressionsanalysen wurden die Zusammenhänge zwischen
Gesundheitskompetenz (HLS-EU-Q16) und Versorgungsaspekten (RehaQ-N1) untersucht.

Ergebnisse Die Ergebnisse zeigen, dass 35,8% der Befragten eine problematische
und 17,9% eine inadäquate GK aufwies. Die subjektiven Bedarfe waren mehrheitlich
ungedeckt und 47,7% der Betroffenen waren mit der erhaltenen Therapie
unzufrieden.

Schlussfolgerung In der vorliegenden Studie schätzten Long-COVID Betroffene
ihre Gesundheitskompetenz verhältnismäßig gering ein. Das Gesundheitssystem scheint
wenig auf die Betroffenen vorbereitet zu sein, was sich in ungedeckten Bedarfen und
niedriger Behandlungszufriedenheit niederschlägt – insbesondere bei Betroffenen mit
geringer GK.
Careers in Skull Base and Open Cerebrovascular Surgery: Factors Associated with Academic Job Placement
Authors: Dyess Garrett A. , Ghalib Mohammed Anas , Taylor Zachary , Sabetta Zackary , Taylor Ethan , Butler Danner , Bassett Maxon , Harris Luke , Bolus Harris , Shahid Adnan , Thakur Jai D.
Published: July 2024

Introduction Fellowship training has become increasingly sought after by neurosurgeons aiming for academic careers over the last two decades. This study assesses American Board of Neurological Surgeons board-certified neurosurgeons specializing in skull base or open cerebrovascular surgery between 2013 and 2023, focusing on identifying academic career predictors through demographic and academic outputs.

Methods The study utilized the American Association of Neurological Surgeons Neurosurgical Fellowship Training Program Directory to identify neurosurgeons certified from 2013 to 2023, gathering demographic details and academic productivity from Scopus.

Results Among 173 neurosurgeons, 87.86% were male, 36.36% were graduates from top 40 National Institutes of Health-funded medical schools, and 49.42% completed their residency in highly ranked departments. In univariate analysis, predictors for an academic career included publishing in the field before residency (p = 0.03054), a higher h-index before and after residency (p = 0.03976 and 0.0003101), and increased publication volume during and up to 3 years post-fellowship (2.284e-06). Multivariate analysis found that publication volume during and up to 3 years post-fellowship (odds ratio [OR] = 4.98, 95% confidence interval [CI]: 2.07–11.9, p = 0.0003) and basic science publications (OR = 2.4, 95% CI: 1.05–5.49, p = 0.038) were the most significant predictors of academic career placement.

Conclusion The study underscores the strong link between the academic career success of neurosurgeons trained in skull base and open cerebrovascular surgery and their research productivity, particularly publication volume during key career stages and involvement in basic science research. This highlight sustained research activity as a critical determinant of academic career achievement, surpassing the influence of training institution prestige.
Design and Development of a Self-nanoemulsifying Drug Delivery System for Co-delivery of Curcumin and Naringin for Improved Wound Healing Activity in an Animal Model
Authors: Shah Ismail , Shafique Muhammad , Hayat Ajmal , Jabbar Abdul , Ullah Shafi , Shah Muhammad Raza , Balouch Aziz , Gul Farah
Published: July 2024

The present study endeavored to design and develop a self-nanoemulsifying drug delivery system to improve the solubility and dermatological absorption of curcumin and naringin. Curcumin and naringin-loaded self-nanoemulsifying drug delivery system formulations were developed using aqueous phase titration. Phase diagrams were used to pinpoint the self-nanoemulsifying drug delivery system zones. Tween 80 and Labrasol (surfactants), Transcutol (cosurfactant), and cinnamon oil were chosen from a large pool of surfactants, cosurfactants, and oils based on their solubility and greatest nano-emulsion region. Fourier transform infrared spectroscopy, zeta sizer, and atomic force microscopy were used to characterize the optimized formulations and test for dilution and thermodynamic stability. The optimized curcumin-naringin-self-nanoemulsifying drug delivery system demonstrated the following characteristics: polydispersity index (0.412 ± 0.03), % transmittance (97%), particle size
(212.5 ± 05 nm), zeta potential (− 25.7 ± 1.80 mV) and having a smooth and spherical droplet shape, as shown by atomic force microscopy. The ability of their combined formulation to cure wounds was tested in comparison to pure curcumin suspension, empty self-nanoemulsifying drug delivery system, and standard fusidic acid. Upon topical administration, the optimized curcumin-naringin-self-nanoemulsifying drug delivery system demonstrated significant wound healing activity in comparison with a pure curcumin suspension, empty self-nanoemulsifying drug delivery system, and standard fusidic acid. Based upon this result, we assume that skin penetration was increased by using the optimized curcumin-naringin-self-nanoemulsifying drug delivery system with enhanced solubility.
Examining Neural Correlates of Sexual Preferences between Persian Homo- and Heterosexual Males Using Psychological Assessments and Functional Magnetic Resonance Imaging in Specifying Cognitive Map: A Limited and Cross-sectional Study
Authors: Khorshidi Abdollah
Published: July 2024

Although the brain is an important part of a person's sexual life, little is known about the correlations between sexual response and brain activation. This study examines brain responses through clinical testing to reveal several brain structures whose activation is relevant to sexual arousal besides psychological testing according to the common traditional values and standards of Iranian society. Based on an initial self-report, 25 homosexual and 25 heterosexual males participated in this test to elucidate the identity and sexual trends via the Minnesota Multiphasic Personality Inventory (MMPI-2). Also, an fMRI technique—by presenting distinct homo- and heterosexual sex erotic pictures during the test—was employed in neural correlates of sexual arousal via blood oxygen level dependent (BOLD) signal measuring and Statistical Parametric Mapping analysis. In five selected homosexuals by the most appropriate MMPI test score, brain activities were significantly detected in the midbrain, amygdala, anterior cingulate gyrus, frontal cortex, orbitofrontal cortex, globus pallidus, thalamus, and putamen when the participant saw the erotic pictures during the test, which were responsive to sexual arousal. Also, bilateral caudate nucleus, left angular gyrus, and bilateral pallidum were activated but five selected heterosexuals showed no activation in these areas (p < 0.001). Likewise, the MMPI method confirmed that homosexuality was relevant to diverse life positions, and biological and socioeconomic aspects. The maximum positive correlations were pairwise found in the parietal lobule by r = 0.61 (p < 0.05) and in the frontal gyrus by r = 0.64 (p = 0.10), and the minimum negative correlations were in globus pallidus by r = − 0.18 (p < 0.10) and r = − 0.16 (p < 0.10) for homosexuals and heterosexuals, correspondingly. These results may be useful for understanding the different neural mechanisms of personality recognition and sexual orientation changes while incorporating the individual's history and experience simultaneously into the assessment.
The Spectrum of Childhood-Onset Lower Motor Neuron Disease of Spinal Muscular Atrophy Phenotype Associated with Survival Motor Neuron-2 Gene Deletion
Authors: Ganguly Somenath , Chakraborty Durga Prasad , Roychoudhury Satyabrata , Nandi Madhumita , Das Suman
Published: July 2024

Pediatric lower motor neuron disease is clinically and genetically heterogeneous. We characterized disease progression among children with the spinal muscular atrophy (SMA) phenotype having 2:0 (group A) and 2:1 (group B) of the survival motor neuron 1/2 (SMN1:SMN2) genotype over 1 year. We included children aged 0 to 12 with the SMA phenotype between January 2018 and December 2021. Their demographic, clinical (Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders [CHOP-INTEND] scores), electrophysiological, radiological, and genetic data were collected from past medical records. The sequential CHOP-INTEND scores and the compound muscle action potential (CMAP) amplitudes were compared using an analysis of covariance test, controlling for age and sex. A linear regression was run to determine the association between the ages of the patients and the CHOP-INTEND scores. Among nine children in group A and six in group B, the decline of the mean (standard deviation) CHOP-INTEND score from the initial value to the 12th-month follow-up value was significant only in group A. CHOP-INTEND scores did not significantly differ between the two groups at the first admission but were significantly lower in group A at the subsequent visits. Group A patients had significantly lower CMAP amplitudes than patients in group B. There was a moderate, negative association between the age of patients and the CHOP-INTEND scores in group A. Group A patients had a significantly higher age-dependent decline in CHOP-INTEND scores and CMAP values than group B, although their age and the severity of weakness did not significantly differ at presentation.
A Prospective Comparative Study of Ray Resection versus Amputation through Proximal Phalanx for Nonviable Digits of Upper Limb
Authors: Kumar Rajesh , John Jerry R. , Gupta Tarush , Sharma Ramesh K.
Published: July 2024

Background Finger amputations aim at preserving function and optimizing cosmesis. The crucial decision here is whether to preserve a stump or to do a ray amputation. The present study aimed to compare the functional outcome and postoperative quality of life after ray amputation or amputation through the proximal phalanx.

Materials and Methods A prospective study was conducted from January 2019 to June 2020 in patients requiring single-finger amputation through the proximal phalanx or metacarpal. Patients were divided into two groups; Group A: amputation through the proximal phalanx and Group B: ray amputation of the finger. The following functional parameters were assessed: grip strength, hand circumference, palmar volume, and webspace span. The Michigan Hand Outcomes Questionnaire (MHQ) score was employed to score hand function and aesthesis at 6 months in both hands.

Results Thirty patients were enrolled. Findings in 26 patients (52 hands) were subjected to further analysis, 12 in Group A and 14 in Group B. Patients in both groups lost grip strength significantly compared with their contralateral normal hands (29.22 ± 14.88 [Group A] and 34.57 ± 19.12 [Group B]); however, it was statistically nonsignificant between the two groups. There was reduced mean palmar circumference in both groups' involved hands, but the decrease in circumference was statistically significant, only for Group B. Group B patients scored better in all the six subscales of the MHQ; however, only the Aesthetics score was significantly superior. The operated hand's webspace span increased significantly with respect to the normal contralateral web by a mean of 4.55 mm.

Conclusion The study concluded that both the surgical options for the level of amputation should be discussed with the patients in detail, taking into account their occupational and personal requirements. Our study findings will help to objectively counsel the patients regarding expectations in functional and aesthetic outcomes following either technique.
Trauma or in search of lost agency
Authors: Martínez Ruiz Rosaura
Published: July 2024

The purpose of this article is to explore the healing power of psychoanalytic narrating of trauma and its being listened to as a way of recovering the agency that violence has stripped away. Based on the Freudian theory of trauma, Judith Butler’s theory of subjection and Hannah Arendt’s theory of action, I analyze how agency is not a full a priori but rather an a posteriori construction achieved, in a deferred manner, in the story told to another who listens.
The challenge of non-Markovian energy balance models in climate
Authors: Watkins Nicholas W. , Calel Raphael , Chapman Sandra C. , Chechkin Aleksei , Klages Rainer , Stainforth David A.
Published: July 2024

We first review the way in which Hasselmann’s paradigm, introduced in 1976 and recently honored with the Nobel Prize, can, like many key innovations in complexity science, be understood on several different levels. It can be seen as a way to add variability into the pioneering energy balance models (EBMs) of Budyko and Sellers. On a more abstract level, however, it used the original stochastic mathematical model of Brownian motion to provide a conceptual superstructure to link slow climate variability to fast weather fluctuations, in a context broader than EBMs, and led Hasselmann to posit a need for negative feedback in climate modeling. Hasselmann’s paradigm has still much to offer us, but naturally, since the 1970s, a number of newer developments have built on his pioneering ideas. One important one has been the development of a rigorous mathematical hierarchy that embeds Hasselmann-type models in the more comprehensive Mori–Zwanzig generalized Langevin equation (GLE) framework. Another has been the interest in stochastic EBMs with a memory that has slower decay and, thus, longer range than the exponential form seen in his EBMs. In this paper, we argue that the Mori–Kubo overdamped GLE, as widely used in statistical mechanics, suggests the form of a relatively simple stochastic EBM with memory for the global temperature anomaly. We also explore how this EBM relates to Lovejoy et al.’s fractional energy balance equation.
Source size of x rays from self-modulated laser wakefield accelerators
Authors: Pagano I. M. , Lemos N. , King P. M. , Rusby D. , Sinclair M. , Aghedo A. , Khan S. , Downer M. C. , Joshi C. , Albert F.
Published: July 2024

A comparative study of x-ray sources generated with different mechanisms from self-modulated laser wakefield acceleration (SM-LWFA) electrons was performed to compare the source size or spatial resolution for use in high energy density science applications. We examine the source size of betatron, inverse Compton scattering, and bremsstrahlung radiation with a Fresnel diffraction based formalism and a modified x-ray ray tracing model. We observe the dependence of source size on the radiation generation process, laser parameters, and compare to what is possible in other regimes of LWFA, as well as current methods. This information is significant as we begin to explore the use of light sources driven by SM-LWFA for use as a diagnostic at large-scale laser facilities where blowout regime LWFA is not possible.
Rescattering of stimulated Raman side scattering in nonuniform plasmas
Authors: Tan S. , Wang Q. , Chen Y. , Yao W. B. , Xiao C. Z. , Myatt J. F.
Published: July 2024

Rescattering of stimulated Raman side scattering (SRSS) is observed for the first time via two-dimensional (2D) particle-in-cell (PIC) simulations. We construct a theoretical model for the rescattering process, which can predict the region of occurrence of mth-order SRSS and estimate its threshold. The rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion scheme. Hot electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS, but there is no cascade acceleration to produce superhot electrons. Parametric studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.
Assimilating mean velocity fields of a shockwave–boundary layer interaction from background-oriented schlieren measurements using physics-informed neural networks
Authors: Rohlfs L. , Weiss J.
Published: July 2024

We propose a novel method to reconstruct mean velocity fields of turbulent shockwave–boundary layer interactions (SBLIs) from background-oriented schlieren (BOS) measurement data using physics-informed neural networks (PINNs). By embedding the compressible Reynolds-Averaged Navier–Stokes equations into the PINN loss function, we recover a full set of physical variables from only the density gradient as training data. This technique has the potential to generate velocity fields similar to particle image velocimetry (PIV) results from usually simpler planar BOS measurements, at the cost of some computational resources. We analyze our method's capabilities on two oblique SBLI cases: a high-fidelity Mach 2.28 direct numerical simulation dataset for validation and a Mach 2.0 wind tunnel experiment. We demonstrate the positive impact of different wall boundary constraints such as the wall shear stress and pressure distribution for enhancing the PINN's convergence toward physically accurate solutions. The predicted fields are compared with experimental PIV and other point measurements, while we discuss the accuracy, limitations, and broader implications of our approach for SBLI research.
Fault diagnosis of landing gear retraction system with bond graph under uncertain conditions
Authors: Chen Jie , Li Chen , Fan Jingwen , Gao Ke , Sun Chang , Zhang Gaofei
Published: July 2024

Given the lack of sufficient historical data for aircraft landing gear retractor systems, a model-based fault diagnosis approach is needed to overcome this data deficiency. Meanwhile, inherent uncertainties are inevitable in engineering practice, and it is a great challenge to construct a model that accurately reflects the complexity of the actual system under uncertain conditions. Due to the urgent need for reliable model-based diagnostic methods and the need to cope with inherent uncertainties, this paper proposes an improved fault diagnostic method aimed at increasing the diagnostic efficiency of the landing gear retractor system, a critical component in aircraft take-off and landing operations. Due to a lack of historical data, the model-based fault diagnosis method can solve the problem of lack of data. The proposed uncertainty method addresses the challenge of multiple sources of uncertainty by using subsystems to reduce complexity. Fault diagnosis is achieved by comparing residuals with thresholds derived from a diagnostic bond graph (DBG) model. To address the problem of limited fault data, we modeled and simulated the landing gear retractor system using AMESim®. In addition, the linear fractional transform (LFT) approach has been used to resolve parametric uncertainties, but is unable to resolve system structural uncertainties. Therefore, we also analyzed the comparative fault diagnosis results derived from the linear fractional transformation-DBG (LFT-DBG) and the subsystem-DBG approaches. The experimental results support the effectiveness of the subsystem approach in improving fault diagnosis accuracy and reliability, highlighting its potential as a viable diagnostic strategy in aerospace engineering applications.
Optimization of scale inhibitor and adsorption enhancer during squeeze process in offshore oilfields
Authors: Huang Lijuan , Wang Yumeng , Yuan Jiaxiang , Wang Tao , Song Haojun , Li Zongfa , Ren Shaoran
Published: July 2024

To solve the problem that scale in oilfields can lead to a reduction of formation permeability and blockage of wellbore and production system pipelines, through the scale inhibitor-formation water compatibility experiment and the minimum effective scale inhibitor concentration experiment, three different types of surfactants are selected as adsorption promoters. Three different types of surfactants were selected as adsorption–desorption accelerators through dynamic core adsorption–desorption experiments. The results of the indoor experiment show that the three types of scale prevention agents selected can meet the environmental protection requirements of the sea area. The static scale prevention rate at high temperature (>120 °C) exceeds 80%, and the minimum effective concentration is less than 3.5 mg L−1. The preferred cation Gemini surfactant has a stable adsorption enhancement effect of the scale inhibitor under different water-bearing conditions and can effectively extend the squeezing life under complex formation conditions. The results improve the comprehensive economic benefits of the field and provide technical feasibility to significantly improve the scale prevention efficiency of the field.
Tunable coupling of a quantum phononic resonator to a transmon qubit via galvanic-contact flip-chip architecture
Authors: Ruan Xinhui , Li Li , Liang Guihan , Zhao Silu , Wang Jia-heng , Bu Yizhou , Chen Bingjie , Song Xiaohui , Li Xiang , Zhang He , Wang Jinzhe , Zhao Qianchuan , Xu Kai , Fan Heng , Liu Yu-xi , Zhang Jing , Peng Zhihui , Xiang Zhongcheng , Zheng Dongning
Published: July 2024

A hybrid system with tunable coupling between phonons and qubits shows great potential for advancing quantum information processing. In this work, we demonstrate strong and tunable coupling between a surface acoustic wave resonator and a transmon qubit based on the galvanic-contact flip-chip technique. The coupling strength varies from 2π× 7.0 to −2π× 20.6 MHz, which is extracted from different vacuum Rabi oscillation frequencies. The phonon-induced ac Stark shift of the qubit at different coupling strengths is also shown. Our approach offers a good experimental platform for exploring quantum acoustics and hybrid systems.
A rumor propagation model based on nuclear fission
Authors: Zheng Wenrong , Liu Fengming , Sun Yingping
Published: July 2024

The propagation of online rumors is rapid, and its propagation mechanism has always been a research difficulty. In this paper, the network rumors are compared to the nuclear fission process, and a network rumors propagation model is constructed. First, the initial online rumors are compared to neutrons, uranium nuclei are compared to individual rumor receivers, and fission barriers are compared to individual active propagation thresholds. Second, the process of nuclear fission is analyzed and the degree of energy accumulation is used to compare the social impact of online rumors. Finally, the online rumor propagation model based on nuclear fission is constructed. Through experimental simulation, it has been shown that compared to classic infectious disease models, this model can better describe the propagation process of rumors in social networks. Through research and analysis, suggestions for suppressing rumors have been proposed, providing new ideas and references for future researchers.
Strong terahertz pulse induced Pockels and Kerr effect in crystalline quartz for ultrafast pulse switching
Authors: Li Danni , Guo Yingyu , Jin Zuanming , Dong Xiangmei , Zhang Chao , Balakin Alexey V. , Shkurinov Alexander P. , Peng Yan , Zhu Yiming , Zhuang Songlin
Published: July 2024

Ultrafast pulse switching is one of the key elements for ultrahigh speed communication technology. We study the terahertz (THz) induced birefringence response on the laser pulse through the quartz with different THz electric field strength. The magnitude of the observed Pockels signals scales linearly with the THz field amplitude, while the Kerr signals scale quadratically with the THz field amplitude. We demonstrate that the quartz is a good candidate for polarization modulation of 800 nm laser pulse, which has the advantages of low-cost, large bandgap, and negligible dispersion. Furthermore, our investigation finds application beyond ultrafast polarization switching, and the THz-induced polarization gating technique works as a tool for intense THz pulse detection.
What is the impact of successive COVID-19 lockdowns on population mental health? Findings from an Australian natural experiment using health service data
Authors: Lakhani Ali , Sundararajan Vijaya
Published: July 2024

Objective The causal effect of successive population-wide lockdowns in response to increased COVID-19 cases on mental health has yet to be examined using robust methods. A natural experiment design underpinned by objective data can improve our understanding surrounding the definitive impact of social distancing restrictions. Methods The study employed a natural experiment design underpinned by objective data. Health service cost for visits to general practitioners and psychologists and medication dispensing costs served as objective measures of mental health. Difference-in-difference (DID) estimators, which in this study quantify differences in spending changes between groups over time, were produced based on three comparisons: Victoria 2020 lockdown comparison, Victoria 2021 lockdown comparison, and New South Wales (NSW) 2021 lockdown comparison. Specifically, differences in public health service spending during lockdown periods and the same timeframe in 2019 for Victoria and NSW, and control groups (remaining states and territories), were compared. Results Positive estimator values indicate that public health service spending for Victoria and NSW increased more during lockdown periods compared to control states and territories. The Victorian lockdowns of 2020 and 2021, but not the NSW lockdown of 2021, resulted in increased public spending for general practitioner mental health consults (2020 DID estimator: $8498.96 [95% CI $4012.84, $12,373.57], 2021 DID estimator: $6630.06 [95% CI $41.27, $13,267.20], all monetary values in AUD$) and short visits to psychologists (2020 DID estimator: $628.82 [95% CI $466.25, $796.00], 2021 DID estimator: $230.11 [95% CI $47.52, $373.98]). The first Victorian lockdown in 2020 and the NSW lockdown in 2021 resulted in greater spending on short visits to clinical psychologists. Spending on long visits to psychologists and clinical psychologists and medication spending did not change. Conclusions Strict lockdowns can have an adverse impact on population mental health. The impact is particularly evident in those who have a history of previous mental health concerns but does not necessitate extra use of medications, suggesting that psychological care can address the adverse impact of the lockdowns.
Individualised treatment of sexually transmitted infections by rapid molecular assays
Authors: Murray Gerald L. , Sweeney Emma L. , Bradshaw Catriona S.
Published: July 2024

Antimicrobial resistance (AMR) is a major problem in the field of sexually transmitted infections (STIs), where escalating levels have coincided with a surge in infections. The individualised treatment of STIs by rapid molecular ‘resistance’ assays is a new approach to patient management that has developed through understanding of the mechanisms of resistance, combined with nucleic acid amplification diagnostics. Mycoplasma genitalium provides an excellent example of this approach because of a restricted repertoire of effective antibiotics, and resistance mediated by single nucleotide polymorphisms. Detection of one of five M. genitalium 23S rRNA gene mutations is highly predictive of treatment failure with macrolides; employing this diagnostically yields >95% cure with azithromycin. Detection of fluoroquinolone resistance mutations in parC (especially affecting serine 83) and gyrA is predicted to have a similar diagnostic value and is currently being evaluated. This work is underpinned by high quality resistance data, emphasising the importance of ongoing surveillance. Despite some limitations, individualised treatment has demonstrated value in antimicrobial stewardship, extending the use of current therapies despite substantial levels of resistance, reducing prescription of ineffective treatments and sparing last-resort antibiotics.
Identification and characterization of a small-molecule metallophore involved in lanthanide metabolism
Authors: Zytnick Alexa M. , Gutenthaler-Tietze Sophie M. , Aron Allegra T. , Reitz Zachary L. , Phi Manh Tri , Good Nathan M. , Petras Daniel , Daumann Lena J. , Martinez-Gomez Norma Cecilia
Published: July 2024

Many bacteria secrete metallophores, low-molecular-weight organic compounds that bind ions with high selectivity and affinity, in order to access essential metals from the environment. Previous work has elucidated the structures and biosynthetic machinery of metallophores specific for iron, zinc, nickel, molybdenum, and copper. No physiologically relevant lanthanide-binding metallophore has been discovered despite the knowledge that lanthanide metals (Ln) have been revealed to be essential cofactors for certain alcohol dehydrogenases across a diverse range of phyla. Here, we report the biosynthetic machinery, the structure, and the physiological relevance of a lanthanophore, methylolanthanin. The structure of methylolanthanin exhibits a unique 4-hydroxybenzoate moiety which has not previously been described in other metallophores. We find that production of methylolanthanin is required for normal levels of Ln accumulation in the methylotrophic bacteriumMethylobacterium extorquensAM1, while overexpression of the molecule greatly increases bioaccumulation and adsorption. Our results provide a clearer understanding of how Ln-utilizing bacteria sense, scavenge, and store Ln; essential processes in the environment where Ln are poorly bioavailable. More broadly, the identification of this lanthanophore opens doors for study of how biosynthetic gene clusters are repurposed for additional functions and the complex relationship between metal homeostasis and fitness.
Capturing the catalytic intermediates of parkin ubiquitination
Authors: Connelly Elizabeth M. , Rintala-Dempsey Anne C. , Gundogdu Mehmet , Freeman E. Aisha , Koszela Joanna , Aguirre Jacob D. , Zhu Grace , Kämäräinen Outi , Tadayon Roya , Walden Helen , Shaw Gary S.
Published: July 2024

Parkin is an E3 ubiquitin ligase implicated in early-onset forms of Parkinson’s disease. It catalyzes a transthiolation reaction by accepting ubiquitin (Ub) from an E2 conjugating enzyme, forming a short-lived thioester intermediate, and transfers Ub to mitochondrial membrane substrates to signal mitophagy. A major impediment to the development of Parkinsonism therapeutics is the lack of structural and mechanistic detail for the essential, short-lived transthiolation intermediate. It is not known how Ub is recognized by the catalytic Rcat domain in parkin that enables Ub transfer from an E2~Ub conjugate to the catalytic site and the structure of the transthiolation complex is undetermined. Here, we capture the catalytic intermediate for the Rcat domain of parkin in complex with ubiquitin (Rcat–Ub) and determine its structure using NMR-based chemical shift perturbation experiments. We show that a previously unidentified α-helical region near the Rcat domain is unmasked as a recognition motif for Ub and guides the C-terminus of Ub toward the parkin catalytic site. Further, we apply a combination of guided AlphaFold modeling, chemical cross-linking, and single turnover assays to establish and validate a model of full-length parkin in complex with UbcH7, its donor Ub, and phosphoubiquitin, trapped in the process of transthiolation. Identification of this catalytic intermediate and orientation of Ub with respect to the Rcat domain provides important structural insights into Ub transfer by this E3 ligase and explains how the previously enigmatic Parkinson’s pathogenic mutation T415N alters parkin activity.
Heterogeneity in effect size estimates
Authors: Holzmeister Felix , Johannesson Magnus , Böhm Robert , Dreber Anna , Huber Jürgen , Kirchler Michael
Published: July 2024

A typical empirical study involves choosing a sample, a research design, and an analysis path. Variation in such choices across studies leads to heterogeneity in results that introduce an additional layer of uncertainty, limiting the generalizability of published scientific findings. We provide a framework for studying heterogeneity in the social sciences and divide heterogeneity into population, design, and analytical heterogeneity. Our framework suggests that after accounting for heterogeneity, the probability that the tested hypothesis is true for the average population, design, and analysis path can be much lower than implied by nominal error rates of statistically significant individual studies. We estimate each type's heterogeneity from 70 multilab replication studies, 11 prospective meta-analyses of studies employing different experimental designs, and 5 multianalyst studies. In our data, population heterogeneity tends to be relatively small, whereas design and analytical heterogeneity are large. Our results should, however, be interpreted cautiously due to the limited number of studies and the large uncertainty in the heterogeneity estimates. We discuss several ways to parse and account for heterogeneity in the context of different methodologies.
Answers to frequently asked questions about the pulsar timing array Hellings and Downs curve
Authors: Romano J D , Allen B
Published: July 2024

We answer frequently asked questions (FAQs) about the Hellings and Downs correlation curve—the ‘smoking-gun’ signature that pulsar timing arrays (PTAs) have detected gravitational waves (GWs). Many of these questions arise from inadvertently applying intuition about the effects of GWs on LIGO-like detectors to the case of pulsar timing, where not all of it applies. This is because Earth-based detectors, like LIGO and Virgo, have arms that are short (km scale) compared to the wavelengths of the GWs that they detect (≈102–104km). In contrast, PTAs respond to GWs whose wavelengths (tens of light-years) are much shorter than their arms (a typical PTA pulsar is hundreds to thousands of light-years from Earth). To demonstrate this, we calculate the time delay induced by a passing GW along an Earth-pulsar baseline (a ‘one-arm, one-way’ detector) and compare it in the ‘short-arm’ (LIGO-like) and ‘long-arm’ (PTA) limits. This provides qualitative and quantitative answers to many questions about the Hellings and Downs curve. The resulting FAQ sheet should help in understanding the ‘evidence for GWs’ recently announced by several PTA collaborations.
A review of non-Lorentz invariant variable speed of light theories
Authors: Bileska Mila
Published: July 2024

This work re-derives and discusses non-Lorentz invariant variable speed of light (VSL) theories in the context of cosmological problems. Following a thorough introduction to the subject, an explicit solution demonstrating a possible dependence of the speed of light on the cosmological scale factor is presented and analyzed. The parameters of the initial ansatz,

c
(
t
)
=

c
0

a
n

, are constrained by requiring the VSL formulation to be a solution to the flatness and horizon problems. The theoretical section is concluded with a derivation of the change of entropy in a VSL Universe. Even though such findings imply that the speed of light can vary only in non-flat spacetime, an adapted approach using the Generalized Second Law of Thermodynamics is shown to loosen this restriction. Further, in the experimental section, recent evidence for a temporally varying fine structure constant at

≈

4
σ

significance is presented as a potential test for the VSL hypothesis. Overall, this work introduces and evaluates many aspects of non-Lorentz invariant VSL theories whilst encouraging future research and serving as a largely self-sufficient comprehensive overview paper.
FourSTUblack holes shadows
Authors: Sekhmani Yassine , Jyoti Gogoi Dhruba , Myrzakulov Ratbay , Gaetano Luciano Giuseppe , Rayimbaev Javlon
Published: July 2024

In this work, we examine the optical behaviors and thermodynamic phase structures using shadow analysis for fourSTUblack holes. The study is conducted for four cases of charge configurations on the parameter spaceM(q1,q2,q3,q4). As a matter of fact, both the electric charge as a parameter and the parameter spaceM(q1,q2,q3,q4)affect the geometry of the black hole shadow, particularly the size of the shadow. We also introduce a constraint on the charge of the black hole from the observational results of the M87⋆and Sgr A⋆shadow. Furthermore, we show that the electric charge and the parameter spaceM(q1,q2,q3,q4)have a non-trivial impact on the variation of the energy emission rate. Interestingly enough, we find novel scenarios in which the evaporation is slower, which causes the lifetime of the black holes to be considerably elongated. On the other side, the phase structure of fourSTUblack holes is explored for two cases of electric charge configuration. The findings show a perfect correlation between the shadow and event horizon radii. This correlation is, in fact, helpful in discovering the phase transition in terms of the shadow radius. In addition, the microstructure is being analyzed in terms of shadow analysis, providing similar behavior to the ordinary situation of the Ruppeiner formalism.
Measures of solid-state material and powder bed absorptivity in the visible and near IR spectrum with new small homemade integrative spheres
Authors: Nordet Guillaume , Kromer Robin , Arvieu Corinne , Lacoste Eric
Published: July 2024

The absorptivity is a major parameter in laser-matter interaction. It can be measured by different methods (thermal or optical). The already known integrating sphere method is generally used with spheres whose choice of dimensions and architecture is not discussed in the literature. The influence of the parameters of the sphere (size of the sphere, position of the photodiode on the sphere, distance of the photodiode from the sphere, opening of the passage of the laser, distance from sample to the sphere, presence of a baffle in front of the photodiode, sample angle, coating materials) was tested with a mirror of known reflectivity. This study has demonstrated that it is possible to use small integrating spheres for absorptivity measurements. These spheres are home-made by additive manufacturing from a polymer, with the inner walls coated with BaSO4. The optimum experimental conditions for these small spheres are defined, particularly the angle sample. The absorptivity of various materials in the solid state and powder bed was measured for four wavelengths. These measurements were carried out for three sizes of spheres and confirmed the literature results (for example, the absorptivity is measured at 80% for copper at blue wavelength). This small sphere will be adapted to in-situ measurement, particularly in the Laser Powder Bed Fusion process whatever wavelength, particularly new green or blue laser sources, and material.
On soft measurement modeling for predicting photovoltaic power with uncertainty based on the Takagi–Sugeno model
Authors: Ren Zhenxing , Zhou Yu
Published: July 2024

Abstract

Accurate solar power forecast is becoming more essential for safe and reliable power grid operation with the increasing number of grid-connected photovoltaic (PV) power production units. However, PV power exhibits significant output fluctuation due to both external inputs and intrinsic stochasticity in system dynamics. Therefore, an efficient and reliable soft measurement model of PV power with uncertainty is demanded in practice applications. The technique described in this paper captures the impacts produced by the fundamental uncertainty observed in the data, instead of relying on unrealistic assumptions about uncertainty. A soft measurement model using the Takagi–Sugeno fuzzy logic system based on several input–output time series of PV plants is presented in this study. Chebyshev’s inequality from probability theory and statistics is adopted to create the confidence interval-based response envelopes for these time series at each moment. An envelope-based measure of output uncertainty and a center-valued response forecasting model can be obtained by the proposed identification technique. PV datasets are employed to demonstrate the concept, which indicates the proposed soft measurement may outperform existing methods in terms of prediction accuracy. The average values of mean absolute error, root mean squared error, and the correlation coefficient (R) are only 0.0787, 0.1113, and 0.9979. The average values of the prediction interval coverage probability and the prediction interval normalized average width are 0.9806 and 0.1051.
Design of hexapod robot equipped with omnidirectional vision sensor for defect inspection of pipeline’s inner surface
Authors: Guo Zhanshe , Liu Yang , Zhou Fuqiang , Zhang Peiran , Song Zhipeng , Tan Haishu
Published: July 2024

Defect detection of inner surface of precision pipes is a crucial aspect of ensuring production safety. Currently, pipeline defect detection primarily relies on recording video for manual recognition, with urgent need to improve automation, quantification and accuracy. This paper presents a hexapod in-pipe robot with carrying capacity designed to transport the omnidirectional vision sensor to specified location within unreachable pipelines. The feasibility of the robot’s mechanical design and sensor load-carrying module is analyzed using theory calculations, motion simulations and finite element method. To address the challenges of small pixel ratio and weak background changes in panoramic images, a tiny defect segmentor based on ResNet is proposed for detecting tiny defects on the inner surface of pipelines. The hardware and software systems are implemented, and the motion performance of the pipeline robot is validated through experiments. The results demonstrate that the robot achieves stable movement at a speed of over 0.1 m s−1 and can adapt to pipe diameter ranging from of 110 to 130 mm. The novelty of the robot lies in providing stable control of the loaded vision sensor, with control precision of the rotation angle and the displacement recorded at 1.84% and 0.87%, respectively. Furthermore, the proposed method achieves a detection accuracy of 95.67% for tiny defects with a diameter less than 3 mm and provides defect location information. This pipeline robot serves as an essential reference for development of in-pipe 3D vision inspection system.
Fast and accurate phase processing in off-axis digital holography combining adaptive spatial filtering and an embedded GPU platform
Authors: Bai Hongyi , Li Liyang , Sun Laijun , Liu Zeru , Chen Jia , Min Rui
Published: July 2024

Parallel-phase processing enables rapid phase extraction from off-axis digital holograms. To achieve fast and accurate results, the phase reconstruction processes were parallelized using improved filter algorithms and optimized programming strategies. First, an adaptive filtering method based on the Chan–Vese (CV) model which better suits parallelism was designed to extract the +1 term spectrum. We selected suitable computer unified device architecture libraries according to the characteristics of the key phase reconstruction steps. Acceleration technologies, such as virtual memory and shared memory, were used to improve the computational efficiency. Furthermore, we combined an improved 4f optical imaging system with an embedded graphic processing unit (GPU) platform to design a low-cost phase reconstruction system for off-axis digital holography. To verify the feasibility of our method, the reconstructed quality of the CV filtering method was estimated, and the run times of phase retrieval on the central processing unit and embedded GPU were compared for off-axis holograms with different pixel sizes. Additionally, the dynamic fluctuation phase maps of water droplet evaporation were retrieved to demonstrate the real-time capability of the method.
Effect of Bi content and temperature on the shear mechanical properties of Fe-Bi nanocomposites: a molecular dynamics study
Authors: Li Pan , Wang Fazhan , Li Guangyuan , Fan Yuan , Chen Zhanwen , Liu Menghui , Wu Hong
Published: July 2024

In this study, the effects of Bi content and temperature on the mechanical properties of Fe–Bi nanocomposites were investigated using molecular dynamics simulation. The research reveals that the nanocomposite’s shear strength reaches a peak of 3.785 GPa at a Bi content of 0.15%, attributed to the impediment of dislocation movement by twin boundaries during shearing, resulting in a dynamic ‘Hall–Petch’ effect and exceptional shear performance of the material. The abundant twinning induced around Bi phase inclusions introduces orientational disparities within the crystal, leading to grain misalignments, with dislocations in the grains slipping near the twin boundaries. In the nanocomposites, <100> dislocations merely act as initial sites for reactions, reducing their impact on the material’s strength and fracture behavior. The maximum stress decreases with increasing temperature while the magnitude of atomic transformations increases. The proportion of atoms at grain boundaries is higher at higher temperatures, and the arrangement of atoms at grain boundaries is more complex. At a temperature of 100 K, the dislocation density is highest with the smallest variation, forming a reinforced region within the material. The above results have significant implications for the design of environmentally friendly Bi-containing free-cutting steels.
Interface stabilization and propagation in phase field models of solidification: resolving the issue of large driving forces
Authors: Uddagiri Murali , Tegeler Marvin , Steinbach Ingo
Published: July 2024

One of the long-standing problems in the phase field, namely, combining the principles of thermodynamics and capillarity with the numerical aspects of interface propagation in simulations, is re-investigated. Numerical schemes are discussed which allow for stable simulations with arbitrary driving forces, considering or excluding capillarity. We re-investigate a classical stabilization scheme that decouples interface stabilization from curvature evaluation, ensuring stable simulations even under large driving forces. A novel mathematical analysis gives a rigorous estimate for the time stepping and a numerical value of the required stabilization strength. The proposed stabilization scheme is benchmarked for three-dimensional dendritic growth under directional solidification conditions for different solidification speeds.