bluuebunny/crossref_metadata_2025 huggingface dataset:
Spore-based innovative paper-strip biosensor for the rapid detection of ß-lactam group in milk
Authors: Goel Prashant , Vishweswaraiah Raghu Hirikyathanahalli , Kumar Naresh
Published: December 2022

The study's goal was to develop a spore-based paper strip biosensor for detecting ß-lactam antibiotics in milk using the enzyme induction principle. A new spore-based paper strip biosensor has been developed after important operating parameters such as spore volume, substrate volume, exposure time and temperature, and incubation time and temperature were optimised. The limit of detection for various ß-lactam antibiotics, including amoxicillin, penicillin, ampicillin, carbenicillin, cloxacillin, nafcillin, oxacillin, cephalothin, cefalexin, cefoxitin, cefazolin, and cefuroxime, was determined in milk with detection sensitivity of 1 ppb, 2 ppb, 2 ppb, 10 ppb, 10 ppb, 10 ppb, 20 ppb, 10 ppb 1000 ppb, 10 ppb 300 ppb and 100 ppb, respectively. It was also tested with other contaminants such non-ß-lactam antibiotics, pesticides, aflatoxin, heavy metals, and other chemical contaminants, and no interference was found, indicating that the created biosensor had a low rate of false positive and negative results. In comparison to the AOAC-approved CHARM-ROSA ß-lactam strip test, which identified 7 raw milk and zero pasteurised milk samples positive for ß-lactam antibiotics, the sensor was further analysed and verified using 200 raw milk and 105 pasteurised milk samples. This indicates a perfect match between our biosensor and the AOAC-approved CHARM-ROSA ß-lactam strip test. The developed spore-based paper strip biosensors are expected to be useful in the rapid and cost-effective detection of ß-lactam antibiotic residues in milk samples at the dairy farm, reception dock, and production units, respectively.
Elevated endothelial dysfunction-related biomarker levels indicate the severity and predict sepsis incidence
Authors: Zhou Gaosheng , Liu Jingjing , Zhang Hongmin , Wang Xiaoting , Liu Dawei
Published: December 2022

This study was conducted to investigate the relationship between serum endothelial dysfunction-related biomarker levels and organ dysfunction severity in septic patients and the predictive value of these levels during sepsis. In total, 105 patients admitted to the Department of Critical Care Medicine were enrolled between September 2020 and November 2021. Serum syndecan-1 and soluble thrombomodulin(sTM) levels were measured by enzyme-linked immunosorbent assay, and clinical and laboratory data were recorded. Enroll patients were divided into the infection (n = 28), septic nonshock (n = 31), and septic shock (n = 46) groups . Serum syndecan-1 (102.84 ± 16.53 vs. 55.38 ± 12.34 ng/ml), and sTM(6.60 ± 1.44 ng/ml vs. 5.23 ± 1.23 ng/ml, P < 0.01) levels were increased in the septic group compared with those in the infection group. Serum syndecan-1 levels were closely positively correlated with serum sTM (rs = 0.712, r2 = 0.507, P < 0.001). Additionally, serum syndecan-1(rs = 0.687, r2 = 0.472, P < 0.001) and sTM levels (rs = 0.6, r2 = 0.36, P < 0.01) levels were significantly positively correlated with the sequential organ failure assessment scores respectively. Syndecan-1 (AUC 0.95 ± 0.02, P < 0.0001) was more valuable for prediction sepsis than was sTM (AUC 0.87 ± 0.04, P < 0.0001). Compared with sTM (AUC 0.88 ± 0.03, P < 0.001), syndecan-1 (AUC 0.95 ± 0.02, P < 0.001) and SOFA score (AUC 0.95 ± 0.02, P < 0.001) were better predictors of septic shock. Serum syndecan-1 and sTM levels were associated with organ dysfunction severity in septic patients, and both were good predictors for early identification of sepsis, particularly in patients undergoing septic shock.
Turning CO2 into Fuels and Chemicals: An Introduction
Authors: Centi G. , Perathoner S.
Published: December 2022

This introductory chapter analyses the relevance of CO2 to chemicals and fuels, a topic from both scientific and industrial perspectives, assessing especially the relevance of these paths in a future sustainable scenario. A series of elements are especially remarked upon: (i) how to account for the impact in CO2 utilization, (ii) the need to put these routes in the right scenario and (iii) the validity and limits of current techno-economic and life-cycle assessment results. A short analysis of the paths in CO2 conversion to chemicals and fuels is also presented.
Carboxylation with CO2
Authors: Fujihara Tetsuaki
Published: December 2022

Carbon dioxide (CO2) is an ideal source of carbon because it is inexpensive, non-toxic, and abundant. In general, the development of carbon–carbon bond forming reactions is not easy because CO2 is thermodynamically and kinetically stable. However, recent progress in the strategies used for CO2 fixation utilizing transition metals is very useful for catalytic carboxylation toward the synthesis of carboxylic acid derivatives. In this chapter, the recent progress in the transition-metal-catalyzed carboxylation of CO2 is reviewed, including the carboxylation of unsaturated hydrocarbons, organometallic reagents, and organic halides, as well as carboxylation via carbon–hydrogen bond activation.
Carbonylation with CO2
Authors: Cao Ke-Gong , Ran Chuan-Kun , Song Lei , Zhang Zhen , Yu Da-Gang
Published: December 2022

Carbon dioxide (CO2) is an ideal C1 source in organic synthesis since it is non-toxic, abundant, easily accessible and recyclable. Despite a lot of challenges such as thermodynamic stability and kinetic inertness, many research groups have already made significant progress in the application of CO2 to synthesize valuable carbonyl-containing compounds, which are commonly produced by phosgene or oxidative carbonylation with carbon monoxide (CO). The toxicity of carbonylation reagents is a main drawback and many of these methods are limited by the demand of (sub)stoichiometric metal oxidants. As the carbon in CO2 shows the highest valence state, higher than that in CO, CO2 might play a similar role to the combination of CO and oxidants, which can be considered as “CO2 = CO + [O]”. In this chapter, we mainly discuss the process by which CO2 is used as a carbonyl source of carbonylation of different chemical bonds.
Heterogeneous CO2 Hydrogenation
Authors: Hao L. , Sun Z.
Published: December 2022

This chapter mainly focuses on recent advances in CO2 hydrogenation to different products based on heterogeneous catalysts. The reaction pathways and mechanisms for the formation of various products from CO2 hydrogenation are discussed. Special attention is given to the strategies for improving the catalytic selectivity of CO2 hydrogenation. The relationship between the catalytic performance and the structure of the heterogeneous catalysts is highlighted.
Plasmonic Photoreactors for Photocatalytic CO2 Conversion
Authors: Navarrete A. , Solís R. R. , Muñoz-Batista M. J.
Published: December 2022

Ideally, we should follow the example of nature when transforming CO2 and collect solar energy for its chemical conversion into added-value products. The light confinement and tunable wavelength absorption of plasmonic materials makes them an attractive option for photocatalysis; however, flexible and scalable reactors are needed for their wide application. The plasmonic microreactor concept is a tool to not only efficiently harvest light but also tune the thermodynamic state of the reacting mixture. This reactor concept integrates three functions: (1) efficient light transmission through composites based on transparent Aerogels, (2) local activation of the composites with visual light, and (3) integrate the composites and glass microchannels in order to create a “single entity” providing at the same time high surface illumination to the reactor. This chapter first looks into the thermodynamic limits of the photocatalytic conversions, and their connection to the reactor design and modelling. Then, an introduction to the plasmonic photoreactor concept, its assembly and use is given. A reminder of the synthesis and applications of plasmonic materials for the photoreduction of CO2 is also presented. Finally, we present our conclusions and suggest future extension of the concept to operando operation and to the use of metamaterials (metareactors).
Electrochemical CO2 Reduction
Authors: Balamurugan Mani , Merakeb Lydia , Nam Ki Tae , Robert Marc
Published: December 2022

The electrochemical reduction of CO2 has strongly emerged as a promising approach to recycle the gas and generate e-fuels and e-chemicals. It amounts to storing electricity under the form of dense energy and stable chemicals. Toward this goal, metal molecular complexes as well as solid metal based materials may be used as catalysts for generating the target products. Designing efficient catalysts (being both stable, selective and fast) requires understanding the operating mechanisms by which CO2 is reductively transformed. Such a task necessitates combining electrochemical and spectroscopic operando methods, and theoretical calculations. This chapter presents an overview of the recent efforts along these lines. Results and lessons obtained from studies devoted to C1 (e.g. CO, CH3OH, CH4) and C2/C2+ (e.g. ethanol, ethylene, acetic acid, etc.) products are presented, and we further identify the challenges for controlling these processes. All these efforts are mandatory for the emergence of electrochemical technologies able to recycle CO2 on a large scale.
CO2 Hydrogenation With a Dielectric Barrier Discharge Reactor
Authors: Li Sirui , Rebrov Evgeny , Gallucci Fausto , Hessel Volker
Published: December 2022

Hydrogenation of CO2 is a promising way for CO2 utilization due to the possibility of producing a wide range of chemicals including CO, CH4, value-added hydrocarbons and oxygenates. Plasma technology, especially plasma-catalysis, has great potential for the valorisation of CO2 and has attracted much attention in recent years. The technological development in renewable energy and clean hydrogen production facilitates the research in plasma-assisted hydrogenation of CO2 as a green approach for chemical production and energy storage. As a result, there is growing interest in this field and a rapid increase in related research can be expected in the near future. Therefore, it is worthwhile to discuss the development of this technology along with current research gaps. This chapter presents a comprehensive review of research progress in plasma and plasma-catalytic CO2 hydrogenation with a focus on DBD plasma reactors and different catalysts. The status and potential challenges of CO2 methanation as well as the production of methanol and CO are covered. Both the plasma-induced gas phase and surface reaction pathways have been discussed to provide insights of the reaction mechanism. Finally, recommendations of potential directions for future research are given.
Ethanol- and heat-mediated phase change from a kinetic (Z′ = 4) polymorph to a thermodynamic (Z′ = 1) polymorph for an N2,6-diaryl-1,3,5-triazine-2,4-diamine
Authors: Tan Sang Loon , Tan Yee Seng , Bin Shahari Muhammad Syafiq , Junaid Ahmad , Dolzhenko Anton V. , Tiekink Edward R. T.
Published: December 2022

The polymorphic form results from an interplay between global molecular packing and stability of molecular conformation.
Bismuth and antimony halometalates containing photoswitchable ruthenium nitrosyl complexes
Authors: Mikhailov Artem , Korobeynikov Nikita , Usoltsev Andrey , Adonin Sergey A. , Kostin Gennadiy A. , Schaniel Dominik
Published: December 2022

Bi(iii) and Sb(iii) halide compounds combined with a photoswitchable ruthenium nitrosyl unit are reported, opening the way for the preparation of hybrid halide complexes with a variety of photoswitchable complexes.
Rh(iii)-catalyzed [4 + 1] cyclization of aryl substituted pyrazoles with cyclopropanols via C–H activation
Authors: Chen Wenxi , Mao Yan , Wang Min , Ling Fei , Li Changchang , Chen Zhangpei , Yao Jinzhong
Published: December 2022

A rhodium-catalyzed formal [4 + 1]-cyclization reaction of aryl substituted pyrazoles with cyclopropanols via C–H bond activation/cyclization processes to selectively construct a series of carbonyl functionalized pyrazolo[5,1-a]isoindoles is described.
Sulfurized diterpenoids in amber as diagenetic indicators of sulfate-reducing processes in past depositional environments
Authors: Lenen Lauriane , Fradet Alice , Schaeffer Philippe , Gomez Bernard , Adam Pierre
Published: December 2022

Organic sulfur compounds in amber formed by sulfurization processes affecting plant resin terpenoids in past anaerobic sulfate-rich depositional environments were identified.
Assembly of isoxazol-5-one with 2-unsubstituted imidazole N-oxides and aldehydes
Authors: Uvarova Ekaterina S. , Kutasevich Anton V. , Lipatov Egor S. , Mityanov Vitaly S.
Published: December 2022

Polyfunctional isoxazole-5(4H)-one and pyrazol-5(4H)-one derivatives with imidazole moiety are easily constructed via a three-component catalyst-free reaction.
Correction: A photoactive lysosome targeting RuII complex downregulates stemness genes in oral squamous cell carcinoma
Authors: Roy Souryadip , Mitra Paromita , Acharya Sourav , Roy Shantanu Saha , Ghosh Shilpendu , Maji Moumita , Modak Niladri , Ghosh Nirmalya , Acharya Moulinath , Singh Sandeep , Mukherjee Arindam
Published: December 2022

Correction for ‘A photoactive lysosome targeting RuII complex downregulates stemness genes in oral squamous cell carcinoma’ by Souryadip Roy et al., Inorg. Chem. Front., 2022, 9, 5840–5852, https://doi.org/10.1039/D2QI01079H.
Synergistic interactions of binary suspensions of magnetic anisotropic particles
Authors: Thelen Thomas , Jara Adriana , Torres-Díaz Isaac
Published: December 2022

We simulate suspensions of particles with shape anisotropy using the ellipsoid–dipole model. We report the effect of shape anisotropy and dipolar interaction on the structures and the macroscopic properties of binary mixtures.
Settling mode of a bottom-heavy squirmer in a narrow vessel
Authors: Tingting Qi , Jianzhong Lin , Zhenyu Ouyang , Jue Zhu
Published: December 2022

The lattice Boltzmann-immersed boundary (IB-LB) method is used to numerically simulate the sedimentation motion of a single two-dimensional, bottom-heavy squirmer in a narrow vessel.
A numerical study on the role of instabilities on multi-wavelength emission signatures of blazar jets
Authors: Acharya Sriyasriti , Vaidya Bhargav , Kalpa Dihingia Indu , Agarwal Sushmita , Shukla Amit
Published: December 2022

Context. Blazars, a class of active galaxies whose jets are relativistic and collimated flows of plasma directed along the line of sight, are prone to a slew of magnetohydrodynamic (MHD) instabilities. These jets show characteristic multi-wavelength and multi-timescale variabilities.

Aims. We aim to study the interplay of radiation and particle acceleration processes in regulating the multi-band emission and variability signatures from blazars. In particular, the goal is to decipher the impact of shocks arising due to MHD instabilities in driving the long-term variable emission signatures from blazars.

Methods. To this end, we performed relativistic MHD (RMHD) simulations of a representative section of a blazar jet. The jet was evolved using a hybrid Eulerian-Lagrangian framework to account for radiative losses due to synchrotron process as well as particle acceleration due to shocks. Additionally, we incorporated and validated radiative losses taking into consideration the external Compton (EC) process that is relevant for blazars. We further compared the effects of different radiation mechanisms through numerical simulation of 2D slab jet as a validation test. Finally, we carried out a parametric study to quantify the effect of magnetic fields and external radiation field characteristics by performing 3D simulations of a plasma column. The synthetic light curves and spectral energy distribution (SEDs) were analyzed to qualitatively understand the impact of instability driven shocks.

Results. We observed that shocks produced with the evolution of instabilities give rise to flaring signatures in the high-energy band. The impact of such shocks is also evident from the instantaneous flattening of the synchrotron component of the SEDs. At later stages, we observed the transition in X-ray emission from the synchrotron process to that dominated by EC. The inclusion of the EC process also gives rise to γ-ray emission and shows signatures of mild Compton dominance that is typically seen in low-synchrotron peaked blazars.
Superflares on solar-like stars
Authors: Vasilyev V. , Reinhold T. , Shapiro A. I. , Krivova N. A. , Usoskin I. , Montet B. T. , Solanki S. K. , Gizon L.
Published: December 2022

Context. Over the past years, thousands of stellar flares have been detected by harvesting data from large photometric surveys. These detections, however, do not account for potential sources of contamination such as background stars or small Solar System objects appearing in the same aperture as the primary target.

Aims. We present a new method for identifying the true flare sources in large photometric surveys using data from the Kepler mission as an illustrative example. The new method considers not only the brightness excess in the stellar light curves, but also the location of this excess in the pixel-level data.

Methods. Potential flares are identified in two steps. First, we search the light curves for at least two subsequent data points exceeding a 5σ threshold above the running mean. For these two cadences, we subtract the “quiet” stellar flux from the Kepler pixel data to obtain new images where the potential flare is the main light source. In the second step, we use a Bayesian approach to fit the point spread function of the instrument to determine the most likely location of the flux excess on the detector. We match this location with the position of the primary target and other stars from the Gaia DR2 catalog within a radius of 10 arcsec around the primary Kepler target. When the location of the flux excess and the target star coincide, we associate the event with a flare on the target star.

Results. We applied our method to 5862 main-sequence stars with near-solar effective temperatures. From the first step we found 2274 events exceeding the 5σ level in at least two consecutive points in the light curves. Applying the second step reduced this number to 342 superflares. Of these, 283 flares occurred on 178 target stars and 47 events are associated with fainter background stars; in 10 cases the flare location could not be distinguished between the target and a background star. We also present cases where flares were reported previously but our technique could not attribute them to the target star.

Conclusions. We conclude that identifying outliers in the light curves alone is insufficient to attribute them to stellar flares and that flares can only be uniquely attributed to a certain star when the instrument pixel-level data together with the point spread function are taken into account. As a consequence, previous flare statistics are likely contaminated by instrumental effects and unresolved astrophysical sources.
HyGAL: Characterizing the Galactic ISM with observations of hydrides and other small molecules
Authors: Kim W.-J. , Schilke P. , Neufeld D. A. , Jacob A. M. , Sánchez-Monge Á. , Seifried D. , Godard B. , Menten K. M. , Walch S. , Falgarone E. , Veena V. S. , Bialy S. , Möller T. , Wyrowski F.
Published: December 2022

As a complement to the HyGAL Stratospheric Observatory for Infrared Astronomy Legacy Program, we report the results of a groundbased absorption line survey of simple molecules in diffuse and translucent Galactic clouds. Using the Institut de Radioastronomie Millimétrique (IRAM) 30 m telescope, we surveyed molecular lines in the 2 mm and 3 mm wavelength ranges toward 15 millimeter continuum sources. These sources, which are all massive star-forming regions located mainly in the first and second quadrants of the Milky Way, form the subset of the HyGAL sample that can be observed by the IRAM 30 m telescope. We detected HCO+ absorption lines toward 14 sightlines, toward which we identified 78 foreground cloud components, as well as lines from HCN, HNC, C2H, and c-C3H2 toward most sightlines. In addition, CS and H2S absorption lines are found toward at least half of the continuum sources. The spectral line data obtained were analyzed to characterize the chemical and physical properties of the absorbing interstellar medium statistically. The column density ratios of the seven molecular species observed are very similar to values found in previous absorption line studies carried out toward diffuse clouds at high latitudes. As expected, the C2H and c-C3H2 column densities show a tight correlation with that of N(HCO+), because of these all these molecules are considered to be proxies for the H2 column density toward diffuse and translucent clouds. The HCN and HNC column densities, by contrast, exhibit nonlinear correlations with those of C2H, c-C3H2, and HCO+, increasing rapidly at Av ≈ 1 in translucent clouds. Static Meudon photodissociation region (PDR) isobaric models that consider ultraviolet-dominated chemistry were unable to reproduce the column densities of all seven molecular species by just a factor of a few, except for H2S. The inclusion of other formation routes driven by turbulent dissipation could possibly explain the observed high column densities of these species in diffuse clouds. There is a tentative trend for H2S and CS abundances relative to H2 to be larger in diffuse clouds (X(H2S) and X(CS) ~ 10−8−10−7) than in translucent clouds (X(H2S) and X(CS) ~ 10−9−10−8) toward a small sample; however, a larger sample is required in order to confirm this trend. The derived H2S column densities are higher than the values predicted from the isobaric PDR models, suggesting that chemical desorption of H2S from sulfur-containing ice mantles may play a role in increasing the H2S abundance.
Cerebrospinal fluid levels of sortilin-1, lipocalin-2, autotaxin, decorin and interleukin-33 in patients with idiopathic intracranial hypertension
Authors: Dündar Ahmet , Arıkanoğlu Adalet , Özdemir Hasan Hüseyin , Aslanhan Hamza , Çevik Mehmet Uğur
Published: December 2022

Background Idiopathic intracranial hypertension (IIH) is characterized by increased cerebrospinal fluid (CSF) pressure of unknown cause. It has been suggested that the inflammatory process plays a role in the pathophysiology of the disease. Sortilin-1, lipocalin-2, autotaxin, decorin, and interleukin-33 (IL-33) are among the factors involved in inflammatory processes.

Objective To investigate the CSF levels of sortilin-1, lipocalin-2, autotaxin, decorin, and IL-33 in patients with IIH.

Methods A total of 24 IIH patients and 21 healthy controls were included in the study. Demographic characteristics of the patients and of the control group as well as CSF pressures were evaluated. Sortilin-1, lipocalin-2, autotaxin, decorin and IL-33 levels in the CSF were measured.

Results The CSF levels lipocalin-2, sortilin-1, autotaxin, IL-33 and CSF pressure were significantly higher in the patients group compared with the control group (p < 0.001). Decorin levels were reduced in patients (p < 0.05). There was no correlation between the autotaxin and IL-33 levels and age, gender, CSF pressure, and body mass index. The results of our study showed that inflammatory activation plays an important role in the development of the pathophysiology of IIH. In addition, the fact that the markers used in our study have never been studied in the etiopathogenesis of IIH is important in explaining the molecular mechanism of this disease.

Conclusion Studies are needed to evaluate the role of these cytokines in the pathophysiology of the disease. It is necessary to evaluate the effects of these molecules on this process.
Fatigue in amyotrophic lateral sclerosis and correlated factors
Authors: Alencar Mariana Asmar , Soares Bruna Laura , Rangel Marcela Ferreira de Andrade , Abdo Juliana Silva , Almeida Rayane Alves Pereira de , Araújo Caroline Martins de , Souza Leonardo Cruz de , Gomes Gisele de Cássia
Published: December 2022

Background Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that leads to muscle weakness and paralysis. Fatigue is a disabling symptom, frequently reported in ALS, but remains under-investigated in this population. Thus, an accurate investigation of this symptom and possible associated factors in this clinical condition is needed to assist in the establishment of an adequate treatment approach.

Objective To investigate the presence of fatigue in individuals with ALS and possible factors correlated with this symptom.

Methods Sixty-five individuals with sporadic ALS participated in the present study. Demographic, clinical, and functional aspects were investigated. Evaluations involved the Fatigue Severity Scale (FSS), ALS Functional Scale (ALSRFS-R), and Quality of Life (QoL) questionnaire (ALSAQ-40). Descriptive and correlation analyses were performed with SPSS statistical program for Windows version 19.0 (IBM Corp., Armonk, NY, USA).

Results Among the 65 individuals evaluated, 44.6% (n = 29) presented fatigue based on the FSS. The mean fatigue intensity was 5.4 ± 1.2 and only 10.4% used a specific medication for fatigue. Differences between the groups with and without fatigue were found regarding sex (p = 0.049), pain intensity (p = 0.026), functioning (p = 0.004), disease severity (p = 0.029), and QoL (p = 0.000). Fatigue was correlated with pain intensity (r = 0.425; p = 0.001), muscle strength (r = - 0.356; p = 0.004), functioning (r = - 0.363; p = 0.003), and QoL (r = 0.481; p = 0.000). No correlations were found with age, time since diagnosis, cramps, or other mobility parameters.

Conclusions Fatigue is a common symptom among individuals with ALS and may be present in all stages of the disease. This symptom was correlated with worse functioning, poorer QoL, greater pain intensity, disease severity, muscle weakness, and the female sex in individuals with ALS.
Gut flora disequilibrium promotes the initiation of liver cancer by modulating tryptophan metabolism and up-regulating SREBP2
Authors: Chen Wen , Wen Liang , Bao Yingying , Tang Zengwei , Zhao Jianhui , Zhang Xiaozhen , Wei Tao , Zhang Jian , Ma Tao , Zhang Qi , Zhi Xiao , Li Jin , Zhang Cheng , Ni Lei , Li Muchun , Liang Tingbo
Published: December 2022

The gut microbiota and liver cancer have a complex interaction. However, the role of gut microbiome in liver tumor initiation remains unknown. Herein, liver cancer was induced using hydrodynamic transfection of oncogenes to explore liver tumorigenesis in mice. Gut microbiota depletion promoted liver tumorigenesis but not progression. Elevated sterol regulatory element-binding protein 2 (SREBP2) was observed in mice with gut flora disequilibrium. Pharmacological inhibition of SREBP2 or
Srebf2
RNA interference attenuated mouse liver cancer initiation under gut flora disequilibrium. Furthermore, gut microbiota depletion impaired gut tryptophan metabolism to activate aryl hydrocarbon receptor (AhR). AhR agonist Ficz inhibited SREBP2 posttranslationally and reversed the tumorigenesis in mice. And, AhR knockout mice recapitulated the accelerated liver tumorigenesis. Supplementation with
Lactobacillus reuteri
, which produces tryptophan metabolites, inhibited SREBP2 expression and tumorigenesis in mice with gut flora disequilibrium. Thus, gut flora disequilibrium promotes liver cancer initiation by modulating tryptophan metabolism and up-regulating SREBP2.
Implications of anomalous relative sea-level rise for the peopling of Remote Oceania
Authors: Sefton Juliet P. , Kemp Andrew C. , Engelhart Simon E. , Ellison Joanna C. , Karegar Makan A. , Charley Blair , McCoy Mark D.
Published: December 2022

Beginning ~3,500 to 3,300 y B.P., humans voyaged into Remote Oceania. Radiocarbon-dated archaeological evidence coupled with cultural, linguistic, and genetic traits indicates two primary migration routes: a Southern Hemisphere and a Northern Hemisphere route. These routes are separated by low-lying, equatorial atolls that were settled during secondary migrations ~1,000 y later after their exposure by relative sea-level fall from a mid-Holocene highstand. High volcanic islands in the Federated States of Micronesia (Pohnpei and Kosrae) also lie between the migration routes and settlement is thought to have occurred during the secondary migrations despite having been above sea level during the initial settlement of Remote Oceania. We reconstruct relative sea level on Pohnpei and Kosrae using radiocarbon-dated mangrove sediment and show that, rather than falling, there was a ~4.3-m rise over the past ~5,700 y. This rise, likely driven by subsidence, implies that evidence for early settlement could lie undiscovered below present sea level. The potential for earlier settlement invites reinterpretation of migration pathways into Remote Oceania and monument building. The UNESCO World Heritage sites of Nan Madol (Pohnpei) and Leluh (Kosrae) were constructed when relative sea level was ~0.94 m (~770 to 750 y B.P.) and ~0.77 m (~640 to 560 y B.P.) lower than present, respectively. Therefore, it is unlikely that they were originally constructed as islets separated by canals filled with ocean water, which is their prevailing interpretation. Due to subsidence, we propose that these islands and monuments are more vulnerable to future relative sea-level rise than previously identified.
Dual regulation of Kv7.2/7.3 channels by long-chain n-alcohols
Authors: Jeong Da-Jeong , Kim Kwon-Woo , Suh Byung-Chang
Published: December 2022

Normal alcohols (n-alcohols) can induce anesthetic effects by acting on neuronal ion channels. Recent studies have revealed the effects of n-alcohols on various ion channels; however, the underlying molecular mechanisms remain unclear. Here, we provide evidence that long-chain n-alcohols have dual effects on Kv7.2/7.3 channels, resulting in channel activation as the net effect. Using heterologous expression systems, we found that n-alcohols could differentially regulate the Kv7.2/7.3 channel depending on their chain length. Treatment with short-chain ethanol and propanol diminished Kv7.2/7.3 currents, whereas treatment with long-chain hexanol and octanol enhanced the currents. However, the long-chain alcohols failed to potentiate Kv7.2 currents pre-activated by retigabine. Instead, they inhibited the currents, similar to short-chain ethanol. The stimulatory effect of the long-chain n-alcohols was also converted into an inhibitory one in the mutant Kv7.2(W236L) channels, while the inhibitory effect of ethanol did not differ between wild-type Kv7.2 and mutant Kv7.2(W236L). The inhibition of currents by n-alcohols was also seen in Kv7.1 channel which does not have the tryptophan (W) residue in S5. These findings suggest that long-chain n-alcohols exhibit dual effects through independent working sites on the Kv7.2 channel. Finally, we confirmed that the hydroxyl group with a negative electrostatic potential surface is essential for the dual actions of n-alcohol. Together, our data suggest that long-chain n-alcohols regulate Kv7.2/7.3 channels by interacting with both stimulatory and inhibitory sites and that their stimulatory action depends on the conserved tryptophan 236 residue in S5 and could be important for triggering their anesthetic effects.
Gravity effects in mass-spring-damper models of inelastic collisions
Authors: Bartz Sean P
Published: December 2022

A ball bouncing on a rigid surface is modeled as a mass-spring-damper system. We consider the effect of including or neglecting the force of gravity, extending previous work that shows that including gravity yields a velocity-dependent coefficient of restitution (COR). This velocity dependence is most pronounced at low-impact velocities and high damping. Previously-published models differ in defining the termination of the collision, with some referencing the ball’s position and others noting when the contact force becomes zero. We propose a new model that combines aspects of these approaches. The various models are compared in their predictions for the COR and collision duration, and are compared to experimental data from a cart on an inclined track bouncing repeatedly on a spring. While the new model shows some improvement over the prior collision termination conditions, the inclusion of gravity is the more important consideration in modeling repeated bouncing.
Control of ion flux-energy distribution at dielectric wafer surfaces by low frequency tailored voltage waveforms in capacitively coupled plasmas
Authors: Hartmann P , Korolov I , Escandón-López J , van Gennip W , Buskes K , Schulze J
Published: December 2022

Capacitively coupled plasmas are routinely used in an increasing number of technological applications, where a precise control of the flux and energy distribution of ions impacting boundary surfaces is required. In the presence of dielectric wafers and targets the accumulation of charges on these surfaces can significantly alter the time evolution of the sheath electric field that is accountable for ion acceleration from the plasma bulk to the surfaces and, thus, lead to parasitic distortions of process relevant ion flux-energy distributions. We apply particle in cell with Monte Carlo collisions simulations to provide insights into the operation, ion acceleration mechanisms, and the formation of such distributions at dielectric wafers for discharges in argon gas. The discharges are driven by a combination of a single high frequency (HF) (27.1 MHz) voltage signal and a low frequency (LF) (100 kHz) customized pulsed voltage waveform. The LF waveform includes a base square signal to realize narrow and controllable high energy peaks of the ion distribution, and steady-slope ramp voltage components. We discuss the distorting effect of dielectric surface charging on the ion flux-energy distribution and provide details about how the voltage ramps can restore its narrow peaked shape. The dependence of the surface charging properties on the LF pulse duty cycle and amplitude, as well as the HF voltage amplitude is revealed. The radial homogeneity of the ion flux is found to be maintained within

±

10

% around the mean value for all quantities investigated. The radial electric field developing at the edge of the dielectric wafer with finite width has only a small influence on the overall homogeneity of the plasma across the whole surface, its effect remains localized to the outermost few mm of the wafer.
Phonon transport mechanism of HfO2 ultrathin film with temperature-correction full-band Monte Carlo simulation
Authors: Chen Hongyu , Wang Zhaoliang , Tang Dawei
Published: December 2022

Hafnium dioxide (HfO2) has been widely used in microelectronics nowadays and commonly withstands extremely high temperatures, so the investigation of its thermodynamic properties is particularly essential. This paper develops a temperature-correction full-band Monte Carlo (TFMC) method to investigate the HfO2 ultrathin film. The phonon dynamics parameters of HfO2 are calculated based on the first-principles method. TFMC can better describe the phonon cumulative distribution function in different temperatures by modifying the phonon relaxation time and heat capacity. The thermal conductivity of HfO2 ultrathin film is calculated based on the above method and is in good agreement with the literature. It is observed that the optical phonons in HfO2 ultrathin film are prominent in the phonon heat transport, which is quite different from the mechanism in common semiconductor materials. Combined with the full-band diffuse mismatch model, the Si-based HfO2 ultrathin film is studied. It is found that the existence of the interface with substrates improves the thermodynamic properties of the ultrathin film, which provides a reference for the selection of substrate materials.
Observation of electronic structure replicas in photoemission spectra of graphite upon adsorption of tin phthalocyanine
Authors: Erk Hermann , Opitz Klaas , Hein Petra , Jauernik Stephan , Bauer Michael
Published: December 2022

Cone-type bands near the center of the surface Brillouin zone were observed in low-energy angle-resolved photoemission spectra of tin phthalocyanine adsorbed on graphite. Simulations in comparison with the experimental data show that the spectral features represent replicas of the electronic structure of graphite near

K
‾

resulting from high-order momentum transfer processes up to the fourth order owing to the interaction of substrate electrons with the long-range structural order of the adsorbate overlayer. The analysis of time-resolved photoemission data from one of the replicas yields a quantitative and very good agreement with previous studies on the excited carrier dynamics in the Dirac cones of graphite and graphene.
Detection algorithm for bearing roller end surface defects based on improved YOLOv5n and image fusion
Authors: Xie Runlin , Zhu Yongjian , Luo Jian , Qin Guofeng , Wang Dong
Published: December 2022

For the current problems of low accuracy and poor reliability of defect detection for bearing roller end surfaces in industrial production, this paper proposes a bearing roller end surface defect detection algorithm based on improved YOLOv5n and the fusion of gamma-corrected maps and curvature maps. First, this paper uses photometric stereo vision to reconstruct the three-dimensional shape of the surface and proposes an improved Frankot–Chellappa integration algorithm to solve the problem of reconstructing surface deformation. Secondly, the DenseFuse network is used to fuse gamma-corrected maps and curvature maps to generate an image dataset that combines the strengths of both images to enhance defect features and improve the precision of target detection. Finally, the improved target detection model YOLOv5n is proposed to detect defects in the end surfaces of bearing rollers. The experimental results show that by using fused images for training, detection models with higher mean average precision(mAP) than traditional images can be obtained, and the improved YOLOv5n algorithm maintains the high real-time performance of the original algorithm while the mAP0.5 and mAP0.5:0.95 of improved YOLOv5n are 98.6% and 87.4%, respectively, which are respectively 0.9% and 2.8% higher than YOLOv5n.
4D lung MRI with high-isotropic-resolution using half-spoke (UTE) and full-spoke 3D radial acquisition and temporal compressed sensing reconstruction
Authors: Wu Can , Krishnamoorthy Guruprasad , Yu Victoria , Subashi Ergys , Rimner Andreas , Otazo Ricardo
Published: December 2022

Objective. To develop a respiratory motion-resolved four-dimensional (4D) magnetic resonance imaging (MRI) technique with high-isotropic-resolution (1.1 mm) using 3D radial sampling, camera-based respiratory motion sensing, and temporal compressed sensing reconstruction for lung cancer imaging. Approach. Free-breathing half- and full-spoke 3D golden-angle radial acquisitions were performed on eight healthy volunteers and eight patients with lung tumors of varying size. A back-and-forth k-space ordering between consecutive interleaves of the 3D radial acquisition was performed to minimize eddy current-related artifacts. Data were sorted into respiratory motion states using camera-based motion navigation and 4D images were reconstructed using temporal compressed sensing to reduce scan time. Normalized sharpness indices of the diaphragm, apparent signal-to-noise ratio (aSNR) and contrast-to-noise ratio (CNR) of the lung tumor (patients only), liver, and aortic arch were compared between half- and full-spoke 4D MRI images to evaluate the impact of respiratory motion and image contrast on 4D MRI image quality. Respiration-induced changes in lung volumes and center of mass shifts were compared between half- and full-spoke 4D MRI measurements. In addition, the motion measurements from 4D MRI and the same-day 4D CT were presented in one of the lung tumor patients. Main results. Half-spoke 4D MRI provides better visualization of the lung parenchyma, while full-spoke 4D MRI presents sharper diaphragm images and higher aSNR and CNR in the lung tumor, liver, and aortic arch. Lung volume changes and center of mass shifts measured by half- and full-spoke 4D MRI were not statistically different. For the patient with 4D MRI and same-day 4D CT, lung volume changes and center of mass shifts were generally comparable. Significance. This work demonstrates the feasibility of a motion-resolved 4D MRI technique with high-isotropic-resolution using 3D radial acquisition, camera-based respiratory motion sensing, and temporal compressed sensing reconstruction for treatment planning and motion monitoring in radiotherapy of lung cancer.
First results of a new quadrupole minimum-B permanent magnet electron cyclotron resonance ion source
Authors: Kalvas T , Toivanen V , Kosonen S T , Koivisto H , Tarvainen O , Maunoury L
Published: December 2022

The first experimental results of a novel permanent magnet electron cyclotron resonance ion source (ECRIS) with a minimum-B quadrupole magnetic field topology are presented. Bremsstrahlung measurements indicate that the electrons can reach energies of 150–200 keV. Ion charge states up to Ar11+ and Kr15+ were detected in the charge state distributions of the extracted beams. Measurements in pulsed operation mode reveal an afterglow peak, which implies that high charge state ions are confined electrostatically similar to a conventional ECRIS. The potential applications and future development of the ion source are discussed.
On the role of helium metastable (23S1) measured by time resolved tunable diode laser spectroscopy in high current magnetron discharge
Authors: Farsy Abderzak El , Morel Erwan , Rozier Yoann , de Poucques Ludovic , Robert Jacques , Minea Tiberiu
Published: December 2022

Tunable diode laser absorption spectroscopy is applied to measure the density and gas temperature of helium metastable (23S1) in the ionization region of magnetron discharge operated at very high current density (

>
10

A

c

m

−
2

), which is achievable in helium at 10 Pa with molybdenum target. Those measurements were combined to electrical characterization of the current and the voltage at the magnetron cathode. The discharge current waveform is anti-correlated with the time-evolution of helium metastable (

H

e

m

) density showing that the main depletion process of

H

e

m

is its ionization. Counterintuitively, the higher the gas temperature the lower the discharge peak current. Gas rarefaction and gas recycling are discussed as major contributors for this phenomenon in very high current glow discharge.
Streamer dynamics and periodical discharge regime transitions under repetitive nanosecond pulses with airflow
Authors: Zhao Zheng , Li Chenjie , Guo Yulin , Zheng Xinlei , Sun Anbang , Li Jiangtao
Published: December 2022

Although the nanosecond repetitively pulsed (NRP) discharge normally stabilizes into one of three regimes (corona/glow/spark) in a pulse train, another nonintuitive instability recently proved that it could periodically swing between corona and spark regimes characterized by repeated spark quenches and reestablishments (Zhao et al 2022 Plasma Sources Sci. Technol.
31 045005). In this paper, we have further investigated the suitability of NRP discharge regime transitions for different pulsed power supplies and revealed dramatic effects of the gas flow on streamer dynamics that possibly lead to spark quenches. Pulse-sequence and temporally resolved electrical and optical diagnostics were implemented to capture discharge evolutions in long pulse trains. Periodical discharge regime transitions under long-term repetitive nanosecond pulses are prevalent under a transmission line transformer pulser and a commercially available FID pulser with parameter constraints. A minimum deposited energy per spark is required for the successive spark pattern. The spark channel before its quench statistically prefers to deviate upstream rather than following the straight axis or intuitively bending downstream to search for more remnants. Before spark quenches, the initial streamer already either exhibits a large radial ‘detour’ or propagates with a zig-zag profile along the periphery of previous spark regions. The periodical discharge regime transition and effects of the gas flow are qualitatively explained based on the plasma–source coupling, evolutions of dominant negative ion composition, and 3D streamer simulation. Periodical NRP spark quenches are probably initiated with the streamer ‘detour’ and then accelerated by the thermal-ionization feedback instability. Inhomogeneous residual charge distribution and accumulations of complex negative ions with high electron bound energies may facilitate the following discharge to search for the gas inlet. In-depth understanding of NRP discharge instabilities could be reached, which are fundamentally governed by residual charge transport and energy relaxation.
Study on heterogeneous Fenton reaction parameters for polishing single-crystal SiC using magnetorheological elastomers polishing pads
Authors: Hu Da , Li Huilong , Lu Jiabin , Yan Qiusheng , Xiong Qiang , Huang Zhanliang , Zhang Fenglin
Published: December 2022

Magnetorheological elastomers (MRE) are intelligent controllable materials used as polishing pads in chemical mechanical polishing (CMP), and the magnetic particles in the MRE polishing pad are used as solid-phase catalysts for heterogeneous Fenton reactions for oxidizing single-crystal SiC surfaces, thereby helping reduce the processing difficulty and obtain high-quality surfaces. The influence of the solid-phase catalyst (Fe3O4 mass fraction, particle size) and polishing solution environment (H2O2 concentration, pH value) on the CMP heterogeneous Fenton reaction polishing single-crystal SiC were investigated. The material removal behavior of the MRE polishing pad was investigated. The results demonstrated that the solid-phase catalyst, Fe3O4, has a better superior effect than the carbonyl iron powder (CIP). The polishing material removal rate (MRR) increased and the surface roughness (Ra
) decreased with an increase in the Fe3O4 mass fraction. Superior polishing results were obtained at a particle size of 0.3 μm. The higher the H2O2 concentration in the polishing solution, the greater the MRR, with lower Ra
at 10% concentration. The highest MRR and lowest Ra
were achieved at pH = 3 in acidic environments. During polishing, the heterogeneous Fenton reaction can significantly enhance the removal ability of polishing materials. The MRR increased by 33.4% with the heterogeneous Fenton reaction compared with those without the heterogeneous Fenton reaction, and the contribution of the heterogeneous Fenton reaction to total material removal was 25.03%. The analysis of the SiC–Abrasive–MRE polishing pad contact state revealed that the heterogeneous Fenton reaction can oxidize the SiC surface and reduce the surface hardness, increasing the indentation depth δwa
of the abrasive grain into the SiC surface and exhibiting greater material removal.