bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Néel Domain Walls Dynamics and Skyrmion Stability Using He Ion Irradiation
Authors: Balan Cristina , van der Jagt Johannes W. , Fassatoui Aymen , Peña Garcia Jose , Jeudy Vincent , Thiaville André , Bonfim Marlio , Vogel Jan , Ranno Laurent , Ravelosona Dafiné , Pizzini Stefania
Published: May 2023

Ion irradiation with light ions is an appealing way to finely tune the magnetic properties of thin magnetic films and in particular the perpendicular magnetic anisotropy (PMA). In this work, the effect of He+ irradiation on the magnetization reversal and on the domain wall dynamics  of Pt/Co/AlOx trilayers is illustrated. Fluences up to 1.5 × 1015 ions cm−2 strongly decrease the PMA, without affecting neither the spontaneous magnetization nor the strength of the interfacial Dzyaloshinskii–Moriya interaction (DMI). This confirms experimentally the robustness of the DMI interaction against interfacial chemical intermixing, already predicted by theory. In parallel with the decrease of the PMA, a strong decrease of the domain wall depinning field is observed after irradiation. This allows the domain walls to reach large maximum velocities with a lower magnetic field compared to that needed for the pristine films. Decoupling PMA from DMI can, therefore, be beneficial for the design of low energy devices based on domain wall dynamics. When the samples are irradiated with larger He+ fluences, the magnetization gets close to the out‐of‐plane/in‐plane reorientation transition, where ≈100nm size magnetic skyrmions are stabilized. It is observed that as the He+ fluence increases, the skyrmion size decreases while these magnetic textures become more stable against the application of an external magnetic field, as predicted by theoretical models developed for ultrathin films with labyrinthine domains.
Molecular Synergistic Passivation for Efficient Perovskite Solar Cells and Self‐Powered Photodetectors
Authors: Chen Chunlei , Zhu Yunfei , Gao Deyu , Li Mengjia , Zhang Zuolin , Chen Hongjian , Feng Yinsu , Wang Chen , Sun Jie , Chen Jiangzhao , Tian He , Ding Liming , Chen Cong
Published: May 2023

The interface between the perovskite and electron‐transporting material is often treated for defect passivation to improve the photovoltaic performance of devices. A facile 4‐Acetamidobenzoic acid (containing an acetamido, a carboxyl, and a benzene ring)‐based molecular synergistic passivation (MSP) strategy is developed here to engineer the SnOx/perovskite interface, in which dense SnOx are prepared using an E‐beam evaporation technology while the perovskite is deposited with vacuum flash evaporation deposition method. MSP engineering can synergistically passivate defects at the SnOx/perovskite interface by coordinating with Sn4+ and Pb2+ with functional group CO in the acetamido and carboxyl. The optimized solar cell devices can achieve the highest efficiency of 22.51% based on E‐Beam deposited SnOx and 23.29% based on solution‐processed SnO2, respectively, accompanied by excellent stability exceeding 3000 h. Further, the self‐powered photodetectors exhibit a remarkably low dark current of 5.22 × 10−9 A cm−2, a response of 0.53 A W−1 at zero bias, a detection limit of 1.3 × 1013 Jones, and a linear dynamic range up to 80.4 dB. This work proposes a molecular synergistic passivation strategy to enhance the efficiency and responsivity of solar cells and self‐powered photodetectors.
Innovation offshoring and reshoring with fully endogenous growth
Authors: Davis Colin , Hashimoto Ken‐ichi
Published: May 2023

This paper studies the implications of innovation offshoring and reshoring for long‐run productivity growth in a North–South framework that features a tension in the firm‐level innovation location decision between accessing technical knowledge in an asset‐wealthy country and sourcing low‐cost high‐skilled labor in an asset‐poor country. We show that, with trade costs and imperfect international knowledge diffusion, industry and innovation tend to concentrate geographically in proximity to the larger market of the asset‐wealthy North when trade costs are high. Investigating the effects of greater economic integration, we find that an improvement in knowledge diffusion increases the share of firms offshoring innovation to the asset‐poor South to take advantage of lower high‐skilled wages, potentially raising the rate of productivity growth. A decrease in trade costs, however, induces firms to reshore innovation to the asset‐wealthy North to take advantage of greater knowledge spillovers, with rising high‐skilled wages potentially lowering the productivity growth rate.
The Role of Thermalization in the Cooling Dynamics of Hot Carrier Solar Cells
Authors: Faber Tim , Filipovic Lado , Koster L. Jan Anton
Published: May 2023

The hot carrier solar cell (HCSC) concept has been proposed to overcome the Shockley Queisser limit of a single p–n junction solar cell by harvesting carriers before they have lost their surplus energy. A promising family of materials for these purposes is metal halide perovskites (MHP). MHPs have experimentally shown very long cooling times, the key requirement of a HCSC. By using ensemble Monte Carlo simulations, light is shed on why cooling times are found to be extended. This article concentrates on the role of thermalization in the cooling process. The role of carrier–phonon and carrier–carrier interactions in thermalization and cooling is specified, while showing how these processes depend on material parameters, such as the dielectric constant and effective mass. It is quantified how thermalization acts as a cooling mechanism via the cold background effect. The importance of a low degree of background doping is to achieve the observed extended cooling times. Herein, it is mapped out how perovskites should be tuned, their material parameters, carrier concentration, and purity, in order to realize a HCSC. It contributes to the debate on the cooling times in MHPs and the suitability of tin perovskites for HCSCs.
Dual Optimization of Back Electrode Interface and Bulk via the Synergistic Passivation Effect of Niobium Pentoxide Enables Efficient Kesterite Solar Cells
Authors: Han Boyang , Song Yanping , Sun Huanhuan , Ma Junjie , Wang Rensheng , Fan Xinlong , Chi Dan , Meng Xiuqing , Huang Shihua , Yao Bin
Published: May 2023

As compared to the predecessor Cu(In,Ga)Se2device, the current efficiency of kesterite Cu2ZnSn(S,Se)4(CZTSSe) solar cells is still much lower mainly due to the known carriers recombination issue within interface and absorber bulk. In contrast to the majority of researches concerning recombination issues that focus on either single absorber bulk or interface passivation strategy, this study is pioneering in constructing synergistic passivation effects (SPE) to address the bulk and interface recombination issue simultaneously. By introducing a novel niobium pentoxide passivation layer into the back electrode interface (BEI), it is identified that SPE can be constructed due to Nb (& O) diffusion from Nb2O5layer to absorber bulk and BEI during high‐temperature selenization. The chemical passivation effect is fulfilled via the intrinsic high resistance characteristic of Nb2O5layer, and also through the NbOxpassivation aiming to absorber bulk benefited from Nb (& O) diffusion. Meanwhile, the occupations of Nb (& O) on the Mo (& Se) sites induce a conduction type inversion in MoSe2interfacial layer and create a preferable interface p+‐Mo(Se,O)2:Nb/CZTSSe, achieving an interfacial field passivation effect. Ultimately, the promoted absorber quality and improved charge carrier transportation from SPE contribute to the boost of device performance beyond 10% efficiency.
Migration and Reaction Mechanism of Barium in BaSO4–CaCO3–Fe2O3 System during Sintering
Authors: Li Sida , Zhang Jianliang , Wang Yaozu , Niu Lele , Lu Fenglin , Wang Tengfei , Liu Zhengjian
Published: May 2023

With the increasingly strict requirements of blast furnaces on the sinter quality, analyzing the phase transition process and reaction mechanism of special elements in the sintering process plays an important role in understanding the sintering process and improving the sinter quality. Herein, the decomposition process of barite during sintering and the influence mechanism on the bonding phase of calcium ferrite are studied by laboratory experiments and thermodynamic calculations. The results show that calcium ferrite and ferric oxide can promote the decomposition of barite and reduce the decomposition temperature in the sintering process. The generated barium enters the calcium ferrite phase and affects the strength and melting point of calcium ferrite. With the increase of barium content, the strength of calcium ferrite sample increases from 1.62 to 2.00 kPa, and the initial melting temperature of calcium ferrite sample stays at 1473 K. However, with the further increase of barium, the sample strength and melting temperature both show a worsening trend. Finally, based on the research results, some suggestions for sintering production are put forward, and the optimal barite content is determined. Results help to better understand the reaction process and action mechanism of barium in the sintering process.
Influence Factors of SEN Clogging of Rare‐Earth Steel Continuous Casting and Solve Ideas of Japanese Steel Enterprises
Authors: Wang Yi , Song Guangjie , He Jianzhong , Zhang Daxian , Fu Jianxun , Shen Ping
Published: May 2023

The clogging behavior of submerged entry nozzle (SEN) is the main reason restricting the continuous casting of steel, which seriously affects the application and popularization of rare‐earth (RE) steel. Through literature analysis, herein, the main influencing factors and mechanism of RE steel continuous casting immersion outlet clogging, and sorts out the main ideas and practices of relevant Japanese enterprises in solving SEN clogging in recent years, are summarized, mainly including the following: 1) optimizing SEN materials to reduce nozzle clogging reactions; 2) using Ar‐blowing SEN; 3) applying electromagnetic field to eliminate charge and inhibiting clogging reaction; and 4) and regulating the composition of molten steel to reduce the possibility of clogging, etc. The combination of these advantages and measures is a feasible way to solve the nozzle clogging of RE steel continuous casting nozzle.
Swelling Behavior of Iron Ore Pellets during Reduction in H2 and N2/H2 Atmospheres at Different Temperatures
Authors: Kovtun Oleksandr , Levchenko Mykyta , Oldinski Erik , Gräbner Martin , Volkova Olena
Published: May 2023

The need to develop green steelmaking techniques has led to the replacement of reducing agents such as CO with H2. H2 and N2/H2 mixtures can be used for the carbothermal reduction of iron ore. Herein, the reduction swelling index (RSI) of iron ore pellets in a forming gas (N2/H2) atmosphere at temperatures of 700–1000 °C is investigated and it is compared with that in pure H2. It is showed in the experimental results that the RSI increases with increasing temperature for both the H2 and N2/H2 atmospheres. The maximum swelling is reached approximately 5 min into the H2 reduction process, while in the N2/H2 atmosphere, it is reached after 25–45 min of reduction, depending on the temperature. When the reduction temperature exceeds 900 °C, the RSI is greater than 20%. Scanning electron microscopy/energy‐dispersive X‐ray spectroscopy is performed to detect the changes in the microstructure and chemical composition of the samples. The nonreduced areas in the reduced pellets during the N2/H2 reduction process are analyzed using light optical microscopy.
Influence of Cr2O3 on the Viscous Flow Behavior and Structure of Cr‐Containing Molten Titanium Slag
Authors: Zeng Ruiqi , Wang Nan , Li Wei
Published: May 2023

Herein, the influence of Cr2O3 on the viscous flow behavior and structure of Cr‐containing molten titanium slag is investigated in this work. The melting and viscosity properties are studied by hemisphere method and rotating cylinder method, respectively. In addition, the structure of Cr‐containing molten titanium slag is investigated by Raman spectroscopy. It is shown in the results that the melting temperature and viscosity both increase with the increase of Cr2O3 content. The activation energy for viscous flow increases with increasing Cr2O3 content, which is in the same trend as viscosity. When the Cr2O3 content increases from 0% to 3%, the simpler 6‐coordinated Ti4+ and TiO44− monomer unit transformed into more complex O–Ti–O deformation and Ti2O64− chain unit. Furthermore, the fraction of relatively complex silicate structural units shows an increasing trend. Cr2O3 behaves as a network former and enhances the degree of polymerization of network structure, and the variation of Cr‐containing molten titanium slag structure is consistent with the increasing trend of viscosity.
Genetic loci regulating the concentrations of anthocyanins and proanthocyanidins in the pericarps of purple and red rice
Authors: Chen Ming‐Hsuan , Pinson Shannon R. M. , Jackson Aaron K. , Edwards Jeremy D.
Published: May 2023

The pigmented flavonoids, anthocyanins and proanthocyanidins, have health promoting properties. Previous work determined that the genes Pb and Rc turn on and off the biosynthesis of anthocyanins (purple) and proanthocyanidins (red), respectively. Not yet known is how the concentrations of these pigmented flavonoids are regulated in grain pericarps. Quantitative trait locus (QTL) analysis in a population of rice (Oryza sativa L.) F5 recombinant inbred lines from white pericarp “IR36ae” x red+purple pericarp “242” revealed three QTLs associated with grain concentrations of anthocyanins (TAC) or proanthocyanidins (PA). Both TAC and PA independently mapped to a 1.5 Mb QTL region on chromosome 3 between RM3400 (at 15.8 Mb) and RM15123 (17.3 Mb), named qPR3. Across 2 years, qPR3 explained 36.3% of variance in TAC and 35.8% in PA variance not attributable to Pb or Rc. The qPR3 region encompasses Kala3, a MYB transcription factor previously known to regulate purple grain characteristics. Study of PbPbRcrc progeny showed that TAC of RcRc near isogenic lines (NILs) was 2.1–4.5x that of rcrc. Similarly, study of PbPbRcRc NILs, which had 70% higher PA than pbpbRcRc NILs, revealed a mutual enhancement, not a trade‐off between these compounds that share precursors. This suggests that Pb and Rc upregulate genes in a shared pathway as they activate TAC and PA synthesis, respectively. This study provides molecular markers for facilitating marker‐assisted selection of qPR3, qPR5, and qPR7 to enhance grain concentrations of pigmented flavonoids and documented that stacking Rc and Pb genes further increases both flavonoid compounds.
In‐vitro toxicity of cyclophosphamide and etoposide intermediates/metabolites produced by three white rot fungi
Authors: Yadav Ankush , Rene Eldon R. , Mandal Mrinal Kanti , Dubey Kashyap Kumar
Published: May 2023

Aim of the present study is to determine the in‐vitro cell cytotoxic effect of native and transformed cancer drugs (cyclophosphamide and etoposide) using three different white rot fungi (Ganoderma lucidum, Phanerochaete chrysosporium and Trametes versicolor). At 3, 6, 9, 12 and 15 days, experiments were done on a mouse monocyte macrophage cell line (Raw 264.7). After biodegradation, the altered compounds were found to be harmful to the Raw 264.7 cells. The maximal cytotoxicity of cyclophosphamide transformed products (TPs) were determined to be 2.4%, 7.3% and 7% respectively, against G. lucidum, P. chrysosporium and T. versicolor, respectively. With G. lucidum, P. chrysosporium and T. versicolor, the etoposide toxicity was 1.5%, 8% and 2.7% respectively. P. chrysosporium‐mediated biodegradation resulted in the maximum toxicity, at 8%, on the 12th day for etoposide and 7.3% on the 3rd day for cyclophosphamide. After biodegradation by fungi, the toxicity of these two anticancer agents was reduced in the form of metabolites, but each fungus showed unique capacity for toxicity removal.
Towards understanding the TiO2 doping at the surface and bulk
Authors: Wach Anna , Zou Xianshao , Wojtaszek Klaudia , Kayser Yves , Garlisi Corrado , Palmisano Giovanni , Sá Jacinto , Szlachetko Jakub
Published: May 2023

Anatase titanium dioxide is a common photocatalyst with limited application scope due to its wide band gap energy. Valence and conduction band doping have long been used to narrow TiO2 band gap energy. The effectiveness of the process is highly dependent on the procedure adopted, and its underlying mechanism remains largely unknown. Importantly, optical changes caused by bulk doping are not always represented at the surface where the catalysis occurs. Therefore, methodologies sensitive to bulk and surface modifications are key for a holistic understanding of the doping mechanism and its effect on photocatalysis quantum yield. Herein, it is proposed the use of X‐ray absorption spectroscopy (XAS) with different probing depths to elucidate the chemical composition of bulk and surface. Soft XAS was employed to determine the chemical state of typical dopants (N and Cu) in TiO2 thin films. The XAS measurements at N K‐edge and Cu L2,3‐edge were performed in surface and bulk‐sensitive detection modes, providing direct insight into the surface‐bulk effects caused by the dopants. In the case of copper doping in the TiO2 conduction band, the data show the formation of Cu2+ in the bulk states. In contrast, the surface states are dominated by Cu+ components resulting from surface termination geometries. Moreover, X‐ray absorption spectra confirmed that the substitutional mechanism is the dominant process in Cu doping. The nitrogen doping was found to be interstitial, causing minor changes to the band structure but affecting the photoluminescence. The proposed methodology closes the gap in knowledge between materials design and photocatalytic performance by establishing atoms' disposition in bulk that affects electronic properties and on the surface that impacts the catalytic cycle.
Demokratische Öffentlichkeit – eine medienpolitische Gestaltungsaufgabe
Authors: Jarren Otfried , Fischer Renate
Published: May 2023

Der aktuelle Medienwandel verändert die Struktur der Öffentlichkeit und beeinflusst dadurch auch politische Prozesse, die für die Konstitution der Demokratie relevant sind. Treibende Kraft des Wandels ist der erfolgreiche Zutritt global agierender privater Plattformen in den Medienmarkt. Ausgehend von der These der Gestaltungsbedürftigkeit von Öffentlichkeit systematisiert der Beitrag demokratische Gewinne und Gefährdungen des plattformisierten Mediensystems: Die Artikulationsmöglichkeiten aller steigen, während die Chancen zur nachvollziehbaren Kontextualisierung, Aggregation und Bewertung von Interessenanmeldungen abnehmen und der Gesamtinklusionsgrad der Öffentlichkeit sinkt. Die zukünftige Medienordnung wird daher zu einer demokratiepolitischen Aufgabe ersten Ranges. Sie muss den funktionalen Besonderheiten, Stärken und Schwächen der jeweiligen Medien, allen voran der Plattformen, Rechnung tragen und das Gesamtsystem der Medien bezogen auf seinen Beitrag zu einer vielfältigen und auf Inklusion angelegten Öffentlichkeit regulieren.
Wer beherrscht die Medien? Zur Einfassung des Journalismus durch Technologiekonzerne
Authors: Theine Hendrik , Tröger Mandy , Sevignani Sebastian
Published: May 2023

Der vorliegende Beitrag zeigt am Beispiel journalistischer Medien in Deutschland, wie Technologiekonzerne alle Ebenen der journalistischen Informationsproduktion und -distribution beeinflussen. Dazu wird der Begriff des media capture zum Konzept des media environment capture erweitert, welches den zunehmenden direkten und indirekten Einfluss von Technologiekonzernen auf journalistische Medienunternehmen erfasst und systematisiert. Gezeigt werden kann, wie vielfältig Konzernentscheidungen auf Medientechnologie, -innovation, -politik und -recht einwirken, medienrelevante Wissenschaft, Forschung und Förderung beeinflussen und auch weit in das Innere der ökonomischen Organisation des Journalismus hineinreichen. Längst sind nicht nur einzelne Orte, Prozesse und Akteure in der Öffentlichkeit privaten Interessen unterworfen, vielmehr wird zusätzlich der Kommunikationsraum zwischen allen an der öffentlichen Debatte partizipierenden Akteur:innen und um sie herum kommerzialisiert.
Kritik und Vertrauen. Einstellungen zu den Medien und vertrauensbildende Maßnahmen der Redaktionen
Authors: Schultz Tanjev
Published: May 2023

Im demokratischen Rechtsstaat werden Macht und Gewalt des Staates eingehegt. Zu den Mechanismen der Kontrolle gehört eine kritische Öffentlichkeit, in der wichtige Informationen verbreitet, gesellschaftliche Diskussionen organisiert und die Mächtigen kritisiert und zur Rechenschaft gezogen werden. Diese demokratische Rolle können die Medien nur ausfüllen, wenn sie genügend Vertrauen bei den Bürger:innen genießen. Der Beitrag zeigt anhand der Daten der „Mainzer Langzeitstudie Medienvertrauen“, wie es um das Vertrauen in das Informations- und Kontrollsystem „Journalismus“ bestellt ist. Mögliche Konstellationen des Miss- und Vertrauens in Medien werden anhand der Beurteilung der Qualität journalistischer Leistungen durch die Publika systematisiert und vertrauensbildende Maßnahmen skizziert, die Politik, Verlage und Redaktionen ergreifen könnten. Langfristiges Ziel solcher Interventionen muss es sein, die Verbindung zwischen der Qualität der Berichterstattung und dem Vertrauen des Publikums zu stärken.
Tech-Lash, what’s next? Drei Strategien zur Demokratisierung der sozialen Medien
Authors: Piétron Dominik
Published: May 2023

Gegenüber der wachsenden Bedeutung von Social-Media-Plattformen und den Großkonzernen, die sie betreiben, hat sich ein allgemeines gesellschaftliches Unbehagen herausgebildet. Sie schaden der Demokratie, fördern Desinformation, verstärken Hetze, manipulieren Nutzer:innen, entziehen der journalistischen Arbeit Werbeeinnahmen und damit finanzielle Ressourcen, lauten einige Vorwürfe. Vor diesem Hintergrund stellt sich die Frage nach den technopolitischen Voraussetzungen einer erfolgreichen Demokratisierung der sozialen Medien. Der Fokus liegt dabei auf der strukturellen Stärkung demokratischer Grundrechte. Drei komplementäre Strategien – staatliche Regulierung der großen Social-Media-Plattformen, Förderung freier und dezentraler Alternativen, gesetzliche Verpflichtung zur Interoperabilität – könnten Privatsphäre, demokratische Repräsentation und Wahlfreiheiten ins digitale Zeitalter retten.
Chancen des Öffentlich-Rechtlichen Rundfunks
Authors: Dobusch Leonhard
Published: May 2023

Der öffentlich-rechtliche Rundfunk steht in der Kritik, seinem gesetzlichen Auftrag nicht adäquat nachzukommen, da vor allem das jüngere Publikum nicht mehr erreicht wird, auch nicht mit den digitalen Angeboten. Von entscheidender Bedeutung ist eine breit verstandene Demokratisierung der öffentlich-rechtlichen Medien, um ihre Legitimität im Digitalzeitalter neu zu begründen und ihre Attraktivität zu erhöhen. Dabei kommt es darauf an, von einer defensiven Fortschreibung einmal etablierter Strukturen in die digitale Welt zu einem offensiven Um- und Ausbau zu gelangen – mit dem Ziel, vielfältiger, inklusiver und demokratischer zu werden. Anhand der drei Bereiche Medienkonsum, Medienproduktion und Mediengovernance arbeitet der Beitrag öffentlich-rechtliche Demokratisierungspotenziale heraus. Allen ist gemein, dass sie sich vor dem Hintergrund neuer digitaler Technologien eröffnen, keineswegs aber automatisch im Zuge der Digitalisierung einstellen.
On two-loop divergences of effective action in 6D, $$ \mathcal{N} $$ = (1, 1) SYM theory
Authors: Buchbinder I. L. , Ivanov E. A. , Merzlikin B. S. , Stepanyantz K. V.
Published: May 2023

Abstract

We study the off-shell structure of the two-loop effective action in 6D,$$ \mathcal{N} $$
N
= (1, 1) supersymmetric gauge theories formulated in $$ \mathcal{N} $$
N
= (1, 0) harmonic superspace. The off-shell effective action involving all fields of 6D,$$ \mathcal{N} $$
N
= (1, 1) supermultiplet is constructed by the harmonic superfield background field method, which ensures both manifest gauge covariance and manifest $$ \mathcal{N} $$
N
= (1, 0) supersymmetry. We analyze the off-shell divergences dependent on both gauge and hypermultiplet superfields and argue that the gauge invariance of the divergences is consistent with the non-locality in harmonics. The two-loop contributions to the effective action are given by harmonic supergraphs with the background gauge and hypermultiplet superfields. The procedure is developed to operate with the harmonic-dependent superpropagators in the two-loop supergraphs within the superfield dimensional regularization. We explicitly calculate the gauge and the hypermultiplet-mixed divergences as the coefficients of $$ \frac{1}{\varepsilon^2} $$

1

ε
2

and demonstrate that the corresponding expressions are non-local in harmonics.
Fate of Quantum Anomalies for 1d lattice chiral fermion with a simple non-Hermitian Hamiltonian
Authors: Chen Wei-Qiang , Wu Yong-Shi , Xi Wenjie , Yi Wei-Zhu , Yue Gen
Published: May 2023

Abstract

It is generally believed that the 1+1D model for a single chiral fermion does not exist by itself alone on lattice. The obstruction to such a lattice realization is the failure to reproduce the quantum anomalies of a chiral fermion in continuum. The conventional way to escape is to associate the anomalous 1d system with a 2d bulk, which is in a topologically non-trivial state, as the boundary of the latter. In this paper, we propose a 1+1D chiral fermion model on 1d spatial lattice, standing alone — without being associated with a 2d bulk — with a simple non-Hermitian hopping Hamiltonian. We demonstrate, using various methods, that the model possesses the same chiral anomaly and gravitational anomaly as in continuum theory. Furthermore, with appropriate parameters, the low energy effective theory of the model remains a field theory for unitary chiral fermions. The essential reason for the success is that the usual “doubled” fermion mode with opposite chirality is rapidly damped out because of non-Hermicity of the Hamiltonian.
CP asymmetry in τ → Kπντ within non-minimal SU(5)
Authors: Faisel Gaber , Khalil S.
Published: May 2023

Abstract

Direct CP asymmetry in semi-leptonic τ decays is an intriguing hint for new physics beyond the standard model. We investigate the CP asymmetry in $$ {\tau}^{-}\to {K}_S^0{\pi}^{-}{\nu}_{\tau } $$

τ
−

→

K
S
0

π
−

ν
τ

and τ− → K−π0ντ decays in the context of the non-minimal SU(5) model, with 45-dimensional Higgs multiplet. We show that the associate color-triplet scalar, which is a natural example of a scalar leptoquark, can mediate the $$ \tau \to s\overline{u}{\nu}_{\tau } $$
τ
→
s

u
¯

ν
τ

transition and account for the observed 2.8 σ discrepancy in $$ {A}_{\textrm{CP}}\left({\tau}^{-}\to {K}_S^0{\pi}^{-}{\nu}_{\tau}\right) $$

A
CP

τ
−

→

K
S
0

π
−

ν
τ

compared to the SM expectation. We also predict a sizable ACP(τ− → K−π0ντ), of $$ \mathcal{O} $$
O
(10−3), which can be experimentally accessible in current and near future experiments.
The pathogenesis of common Gjb2 mutations associated with human hereditary deafness in mice
Authors: Li Qing , Cui Chong , Liao Rongyu , Yin Xidi , Wang Daqi , Cheng Yanbo , Huang Bowei , Wang Liqin , Yan Meng , Zhou Jinan , Zhao Jingjing , Tang Wei , Wang Yingyi , Wang Xiaohan , Lv Jun , Li Jinsong , Li Huawei , Shu Yilai
Published: May 2023

Mutations in GJB2 (Gap junction protein beta 2) are the most common genetic cause of non-syndromic hereditary deafness in humans, especially the 35delG and 235delC mutations. Owing to the homozygous lethality of Gjb2 mutations in mice, there are currently no perfect mouse models carrying Gjb2 mutations derived from patients for mimicking human hereditary deafness and for unveiling the pathogenesis of the disease. Here, we successfully constructed heterozygous Gjb2+/35delG and Gjb2+/235delC mutant mice through advanced androgenic haploid embryonic stem cell (AG-haESC)-mediated semi-cloning technology, and these mice showed normal hearing at postnatal day (P) 28. A homozygous mutant mouse model, Gjb235delG/35delG, was then generated using enhanced tetraploid embryo complementation, demonstrating that GJB2 plays an indispensable role in mouse placenta development. These mice exhibited profound hearing loss similar to human patients at P14, i.e., soon after the onset of hearing. Mechanistic analyses showed that Gjb2 35delG disrupts the function and formation of intercellular gap junction channels of the cochlea rather than affecting the survival and function of hair cells. Collectively, our study provides ideal mouse models for understanding the pathogenic mechanism of DFNB1A-related hereditary deafness and opens up a new avenue for investigating the treatment of this disease.
Singular Griffiths semi-positivity of higher direct images
Authors: Takayama Shigeharu
Published: May 2023

We show that the higher direct image sheaves of the relative canonical bundle tensorized with a Nakano semi-positive vector bundle admit singular Hermitian metrics with Griffiths semi-positive curvature and the minimal extension property.
Strategies for automating analytical and bioanalytical laboratories
Authors: Thurow Kerstin
Published: May 2023

Analytical measurement methods are used in different areas of production and quality control, diagnostics, environmental monitoring, or in research applications. If direct inline or online measurement methods are not possible, the samples taken have to be processed offline in the manual laboratory. Automated processes are increasingly being used to enhance throughput and improve the quality of results. In contrast to bioscreening, the degree of automation in (bio)analytical laboratories is still low. This is due in particular to the complexity of the processes, the required process conditions, and the complex matrices of the samples. The requirements of the process to be automated itself and numerous other parameters influence the selection of a suitable automation concept. Different automation strategies can be used to automate (bio)analytical processes. Classically, liquid handler-based systems are used. For more complex processes, systems with central robots are used to transport samples and labware. With the development of new collaborative robots, there will also be the possibility of distributed automation systems in the future, which will enable even more flexible automation and use of all subsystems. The complexity of the systems increases with the complexity of the processes to be automated.

Graphical Abstract
Patterns of rock pool molluscs in differing shore exposures
Authors: Gonçalves Inês , Vinagre Catarina , Silva Ana
Published: May 2023

Rock pools are understudied systems of extreme importance due to their proven vulnerability to climate change. Rock pool molluscs play essential ecological roles therein, directly by acting both as prey and predator and, indirectly by influencing the macroalgal canopy/vegetation topography via grazing. However, the environmental factors driving their rock pool occupation remain largely unknown. Our study is one of the few to focus on community patterns in rock pool molluscs, particularly at a large scale between shores of differing exposure to wave action, being the first focused assessment of rock pool molluscs in Portugal. Overall, 32 intertidal rock pools on four rocky shores were studied during the summer spring tide of 2015. We used multivariate analysis to evaluate the potential impact of sheltered versus exposed wave action, physical pool structure (length, width, and depth), and relationships within the pool community on the abundance and diversity of molluscs. Wave exposure significantly influenced mollusc abundance and diversity. The majority of the 37 different taxa identified were grazing gastropods (62.2%), followed by bivalves (27.0%) and chitons (10.8%). We suggest that mollusc taxa may have preferences for particular rock pool habitats depending on the type of algae present rather than pool size. We also suggest that species-specific mollusc presence in rock pools can be related to their shell size, aperture, and foot size due to corresponding variation in musculature needed to hold the snail to the substrate in hydrodynamic conditions. Further investigation would benefit from disentangling the potential role of algal pool coverage as a refuge for molluscs.
The role of DSC MR perfusion in predicting IDH mutation and 1p19q codeletion status in gliomas: meta-analysis and technical considerations
Authors: Siakallis Loizos , Topriceanu Constantin-Cristian , Panovska-Griffiths Jasmina , Bisdas Sotirios
Published: May 2023

Purpose

Isocitrate dehydrogenase (IDH) mutation and 1p19q codeletion status are important for managing glioma patients. However, current practice dictates invasive tissue sampling for histomolecular classification. We investigated the current value of dynamic susceptibility contrast (DSC) MR perfusion imaging as a tool for the non-invasive identification of these biomarkers.

Methods

A systematic search of PubMed, Medline, and Embase up to 2023 was performed, and meta-analyses were conducted. We removed studies employing machine learning models or using multiparametric imaging. We used random-effects standardized mean difference (SMD) and bivariate sensitivity-specificity meta-analyses, calculated the area under the hierarchical summary receiver operating characteristic curve (AUC) and performed meta-regressions using technical acquisition parameters (e.g., time to echo [TE], repetition time [TR]) as moderators to explore sources of heterogeneity. For all estimates, 95% confidence intervals (CIs) are provided.

Results

Sixteen eligible manuscripts comprising 1819 patients were included in the quantitative analyses. IDH mutant (IDHm) gliomas had lower rCBV values compared to their wild-type (IDHwt) counterparts. The highest SMD was observed for rCBVmean, rCBVmax, and rCBV 75th percentile (SMD≈ − 0.8, 95% CI ≈ [− 1.2, − 0.5]). In meta-regression, shorter TEs, shorter TRs, and smaller slice thicknesses were linked to higher absolute SMDs. When discriminating IDHm from IDHwt, the highest pooled specificity was observed for rCBVmean (82% [72, 89]), and the highest pooled sensitivity (i.e., 92% [86, 93]) and AUC (i.e., 0.91) for rCBV 10th percentile. In the bivariate meta-regression, shorter TEs and smaller slice gaps were linked to higher pooled sensitivities. In IDHm, 1p19q codeletion was associated with higher rCBVmean (SMD = 0.9 [0.2, 1.5]) and rCBV 90th percentile (SMD = 0.9 [0.1, 1.7]) values.

Conclusions

Identification of vascular signatures predictive of IDH and 1p19q status is a novel promising application of DSC perfusion. Standardization of acquisition protocols and post-processing of DSC perfusion maps are warranted before widespread use in clinical practice.
Transanal formation of anastomosis using C-REX device is feasible and effective in high anterior resection
Authors: Vilhjalmsson Dadi , Lepsenyi Mattias , Syk Ingvar , Grönberg Anders , Thorlacius Henrik
Published: May 2023

Purpose

C-REX is a novel instrument for creating stapleless colorectal anastomosis by compression. The aim of this study was to evaluate the feasibility and effectiveness of C-REX in open and laparoscopic high anterior resections.

Methods

A prospective clinical safety study on 21 patients reconstructed with C-REX colorectal anastomosis following high anterior resection of the sigmoid colon using two different devices for intraabdominal (n = 6) or transanal (n = 15) placement of the anastomotic rings. Any signs of complications were prospectively monitored by a predefined protocol. Anastomotic contact pressure (ACP) was measured via a catheter-based system, and time for evacuation of the anastomotic rings by the natural route was noted. Blood samples were collected daily, and flexible endoscopy was performed postoperatively to examine macroscopic appearance of the anastomoses.

Results

One of six patients operated with the intraabdominal anastomosis technique with an ACP of 50 mBar had to be reoperated because of anastomotic leakage. None of the 15 patients operated with the transanal technique (5 open and 10 laparoscopic procedures) had anastomotic complications, and their ACP ranged between 145 and 300 mBar. C-REX rings were uneventfully expelled by the natural route in all patients after a median of 10 days. Flexible endoscopy showed well-healed anastomoses without stenosis in 17 patients and a moderate subclinical stricture in one patient.

Conclusion

These results indicate that the novel transanal C-REX device is a feasible and effective method for colorectal anastomosis following high anterior resections, irrespective of open or laparoscopic approach. Moreover, C-REX allows measurement of intraoperative ACP and thereby a quantitative evaluation of the anastomotic integrity.
Characterization of clinicopathological features, treatment practices, and outcomes among Finnish advanced breast cancer patients in real-life clinical practice
Authors: Heinolainen Krista , Saarinen Silva , Vertuani Simona , Ellonen Antti , Karlsson Antti , Utriainen Meri , Carlqvist Peter , Mandelin Jami , Holm Barbro
Published: May 2023

Purpose

In recent years, several new targeted therapies have emerged for advanced breast cancer (aBC). However, real-life data specific to aBC and different breast cancer subtypes are scarce. This retrospective cohort study was designed to describe the distribution of aBC subtypes, incidence, treatment patterns, survival, and PIK3CA hotspot mutation frequency.

Methods

The study included all patients in the Hospital District of Southwest Finland diagnosed with aBC between 2004 and 2013 and with a sample available in Auria Biobank. In addition to registry-based data collection, 161 HR+/HER2− aBCs were screened for PIK3CA mutations.

Results

Altogether, 54.7% of the 444 patients included in the study had luminal B subtype. The smallest representations were in HR−/HER2+ (4.5%) and triple-negative (5.6%) subgroups. The percentage of aBC among all diagnosed breast cancers increased until 2010, after which it remained stable. The triple-negative cancers were associated with shorter median overall survival (5.5 months) compared to other subgroups (16.5–24.6 months). Most (84%) triple-negative cancers also metastasized during the first two years, whereas this was more evenly distributed over time in other subgroups. Of the HR+/HER2− tumors, 32.3% harbored a PIK3CA hotspot mutation. These patients, however, did not have inferior survival compared to patients with PIK3CA wild-type cancers.

Conclusion

This study described real-world aBC subgroups and indicated that the clinical outcomes of subgroups vary. Although PIK3CA hotspot mutations did not lead to inferior survival, they are relevant as possible treatment targets. Overall, these data could be utilized to further evaluate the subgroup-specific medical needs in breast cancer.
Crystal chemistry of ferriallanite-(Ce) from Nya Bastnäs, Sweden: Chemical and spectroscopic study
Authors: Sobek Kamil , Losos Zdeněk , Škoda Radek , Holá Markéta , Nasdala Lutz
Published: May 2023

A second study of ferriallanite-(Ce) from Nya Bastnäs, Sweden, extends current data by using electron probe micro-analysis (EPMA), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis and brings new insights about its crystal chemistry obtained by Raman spectroscopy. The study presents the first Raman spectra for ferriallanite-(Ce) member of the allanite group (not considering the rather low-quality spectra published in preceding papers). The material does not show significant radiation damage, which is rare as allanite-group minerals often have undergone metamictisation due to significant amounts of incorporated radionuclides (U, Th). Some interior regions show pronounced zoning that correlates with variations in Raman-band positions. In spite of its significant REE content, the material is virtually non-luminescent. New additional data for allanite-(Ce) from Oßling, Germany and Domanínek, Czech Republic are also presented, which were used for comparison.
Osteosynthesis-associated infection in maxillofacial surgery by bacterial biofilms: a retrospective cohort study of 11 years
Authors: Zirk Matthias , Markewitsch Waldemar , Peters Franziska , Kröger Nadja , Lentzen Max-Philipp , Zoeller Joachim E. , Zinser Max
Published: May 2023

Objectives

The aim of this retrospective cohort study was to determine risk factors for osteosynthesis-associated infections (OAI) with subsequent necessity of implant removal in oral and maxillofacial surgery.

Materials and methods

A total of 3937 records of patients who received either orthognathic, trauma, or reconstructive jaw surgery from 2009 to 2021 were screened for osteosynthetic material removal due to infection. Treatment-intervals, volume of applied osteosynthetic material, and respective surgical procedures were also assessed. Moreover, intraoperatively harvested microbial flora was cultured and subsequently identified by MALDI TOF. Bacteria were then screened for antibiotic resistance via VITEK system or, if necessary, via agar diffusion or epsilometer test. Data was analyzed utilizing SPSS statistical software. For statistical analysis of categorical variables, chi-square tests or Fisher exact tests were used. Continuous variables were compared via non-parametric tests. The level of significance forp-values was set at < 0.05. Descriptive analysis was also performed.

Results

The lower jaw was more prone to OAI than the mid face region. Larger volumes of osteosynthetic material led to significantly more OAI, resulting in reconstruction plates bearing the highest risk for OAI especially when compared to small-volume mini-plates frequently applied in trauma surgery. Among OAI associated with implant volumes smaller than 1500 mm3, the detection ofStreptococcus spp., Prevotella spp., Staphylococcus spp., andVeillonella spp. was significantly elevated, whereas implant volumes larger than 1500 mm3showed a significant increase ofEnterococcus faecalis,Proteus mirabilisandPseudomonas aeruginosa. High susceptibility rates (87.7–95.7%) were documented for 2nd- and 3rd-generation cephalosporines and piperacillin/tazobactam.

Conclusion

High material load and lower jaw reconstruction bear the greatest risks for OAI. When working with large volume osteosynthetic implants, gram-negative pathogens must be considered when choosing an appropriate antibiotic regime. Suitable antibiotics include, e.g., piperacillin/tazobactam and 3rd-generation cephalosporines.

Clinical relevance

Osteosynthetic material utilized in reconstructive procedures of the lower jaw may be colonized with drug-resistant biofilms.
Toward the validation of VR-HMDs for medical education: a systematic literature review
Authors: Pedram Shiva , Kennedy Grace , Sanzone Sal
Published: May 2023

The latest technological advancements in the domain of virtual reality (VR) have created new opportunities to use VR as a training platform for medical students and practitioners more broadly. Despite the growing interest in the use of VR as a training tool, a commonly identified gap in VR-training for medical education is the confidence in the long-term validity of the applications. A systematic literature review was undertaken to explore the extent of VR (in particular head-mounted displays) applications for medical training with an additional focus on validation measures. The papers included in this review discussed empirical case studies of specific applications; however, these were mostly concerned with human–computer interaction and were polarized between demonstrating that a conceptual technology solution was feasible for simulation or looked at specific areas of VR usability with little discussion on validation measures for long-term training effectiveness and outcomes. The review uncovered a wide range of ad hoc applications and studies in terms of technology vendors, environments, tasks, envisaged users and effectiveness of learning outcomes. This presents decision-making challenges for those seeking to adopt, implement and embed such systems in teaching practice. The authors of this paper then take a wider socio-technical systems perspective to understand how the holistic training system can be engineered and validated effectively as fit for purpose, through distillation of a generic set of requirements from the literature review to aid design specification and implementation, and to drive more informed and traceable validation of these types of systems. In this review, we have identified 92 requirement statements in 11 key areas against which a VR-HMD training system could be validated; these were grouped into design considerations, learning mechanisms and implementation considerations.
On computing small variable disjunction branch-and-bound trees
Authors: Gläser Max , Pfetsch Marc E.
Published: May 2023

This article investigates smallest branch-and-bound trees and their computation. We first revisit the notion of hiding sets to deduce lower bounds on the size of branch-and-bound trees for certain binary programs, using both variable disjunctions and general disjunctions. We then provide exponential lower bounds for variable disjunctions by a disjoint composition of smaller binary programs. Moreover, we investigate the complexity of finding small branch-and-bound trees using variable disjunctions: We show that it is not possible to approximate the size of a smallest branch-and-bound tree within a factor of $$\smash {2^{\frac{1}{5}n}}$$

2

1
5

n

in time $$O(2^{\delta n})$$

O
(

2

δ
n

)

with $$\delta <\tfrac{1}{5}$$

δ
<

1
5

, unless the strong exponential time hypothesis fails. Similarly, for any $$\varepsilon > 0$$

ε
>
0

, no polynomial time $$\smash {2^{(\frac{1}{2} - \varepsilon )n}}$$

2

(

1
2

-
ε
)
n

-approximation is possible, unless $$\text {P} = \text {NP} $$

P
=
NP

. We also show that computing the size of a smallest branch-and-bound tree exactly is $${\#P} $$

#
P

-hard. Similar results hold for estimating the size of the tree produced by branching rules like most-infeasible branching. Finally, we discuss that finding small branch-and-bound trees generalizes finding short treelike resolution refutations, and thus non-automatizability results transfer from this setting.
Removal of ammonium and phosphates from aqueous solutions by biochar produced from agricultural waste
Authors: Pantoja F. , Sukmana H. , Beszédes S. , László Z.
Published: May 2023

The concern about protecting water quantity and quality is one of the most severe challenges of the twenty-first century since the demand for water resources grows as the population and its needs grow. Additionally, and as expected, most human activities produce wastewater containing undesirable contaminants. On the other hand, the generation of agricultural waste and its inappropriate disposal causes further problems. Current wastewater treatment methods involve a combination of physical and chemical processes, technologies, and operations to remove pollutants from effluents; adsorption is an excellent example of an effective method for wastewater treatment, and biochar is currently one of the most valuable adsorbents. This review focuses on new research about applying biochar produced from agricultural waste as a low-cost and environmentally friendly method for removing ammonium and phosphates from aqueous solutions.