bluuebunny/crossref_metadata_2025 huggingface dataset:
UCHL1-dependent control of hypoxia-inducible factor transcriptional activity during liver fibrosis
Authors: Collins Amy , Scott Rebecca , Wilson Caroline L. , Abbate Giuseppe , Ecclestone Gabrielle B. , Albanese Adam G. , Biddles Demi , White Steven , French Jeremy , Moir John , Alrawashdeh Wasfi , Wilson Colin , Pandanaboyana Sanjay , Hammond John S. , Thakkar Rohan , Oakley Fiona , Mann Jelena , Mann Derek A. , Kenneth Niall S.
Published: May 2024

Liver fibrosis is the excessive accumulation of extracellular matrix proteins that occurs in most types of chronic liver disease. At the cellular level, liver fibrosis is associated with the activation of hepatic stellate cells (HSCs) which transdifferentiate into a myofibroblast-like phenotype that is contractile, proliferative and profibrogenic. HSC transdifferentiation induces genome-wide changes in gene expression that enable the cell to adopt its profibrogenic functions. We have previously identified that the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) is highly induced following HSC activation; however, the cellular targets of its deubiquitinating activity are poorly defined.

Here, we describe a role for UCHL1 in regulating the levels and activity of hypoxia-inducible factor 1 (HIF1), an oxygen-sensitive transcription factor, during HSC activation and liver fibrosis. HIF1 is elevated during HSC activation and promotes the expression of profibrotic mediator HIF target genes. Increased HIF1α expression correlated with induction of UCHL1 mRNA and protein with HSC activation. Genetic deletion or chemical inhibition of UCHL1 impaired HIF activity through reduction of HIF1α levels. Furthermore, our mechanistic studies have shown that UCHL1 elevates HIF activity through specific cleavage of degradative ubiquitin chains, elevates levels of pro-fibrotic gene expression and increases proliferation rates. As we also show that UCHL1 inhibition blunts fibrogenesis in a pre-clinical 3D human liver slice model of fibrosis, these results demonstrate how small molecule inhibitors of DUBs can exert therapeutic effects through modulation of HIF transcription factors in liver disease. Furthermore, inhibition of HIF activity using UCHL1 inhibitors may represent a therapeutic opportunity with other HIF-related pathologies.
Mechanism of protective actions of sparsentan in the kidney: lessons from studies in models of chronic kidney disease
Authors: Kohan Donald E. , Bedard Patricia W. , Jenkinson Celia , Hendry Bruce , Komers Radko
Published: May 2024

Simultaneous inhibition of angiotensin II AT1 and endothelin ETA receptors has emerged as a promising approach for treatment of chronic progressive kidney disease. This therapeutic approach has been advanced by the introduction of sparsentan, the first dual AT1 and ETA receptor antagonist. Sparsentan is a single molecule with high affinity for both receptors. It is US Food and Drug Administration approved for immunoglobulin A nephropathy (IgAN) and is currently being developed as a treatment for rare kidney diseases, such as focal segmental glomerulosclerosis. Clinical studies have demonstrated the efficacy and safety of sparsentan in these conditions. In parallel with clinical development, studies have been conducted to elucidate the mechanisms of action of sparsentan and its position in the context of published evidence characterizing the nephroprotective effects of dual ETA and AT1 receptor inhibition. This review summarizes this evidence, documenting beneficial anti-inflammatory, antifibrotic, and hemodynamic actions of sparsentan in the kidney and protective actions in glomerular endothelial cells, mesangial cells, the tubulointerstitium, and podocytes, thus providing the rationale for the use of sparsentan as therapy for focal segmental glomerulosclerosis and IgAN and suggesting potential benefits in other renal diseases, such as Alport syndrome.
Research on temperature control of proton exchange membrane electrolysis cell based on MO‐TD3
Authors: Ma Libo , Zhao Hongshan , Pan Sichao
Published: May 2024

To solve the problem of temperature control in proton exchange membrane electrolytic cell (PEMEC), this paper presents a temperature control method based on multi‐experience pool probability playback and Ornstein‐Uhlenbeck noise‐twin delay depth deterministic strategy gradient. Firstly, considering the influence of water supply, anode and cathode pressure, and natural heat dissipation on temperature, a refined thermal model of PEMEC is established and transformed into a Markov model under the framework of deep reinforcement learning (DRL). Then, to solve the training instability and poor control effect of DRL caused by inertia delay of the PEMEC temperature control system, multi‐empirical pool probability playback and Ornstein‐Uhlenbeck random process noise techniques are introduced on the basis of the traditional DRL method. Finally, the simulation and hardware‐in‐the‐loop experience results show that the proposed method outperforms other advanced methods.
Rapid kilonova evolution: Recombination and reverberation effects
Authors: Sneppen Albert , Watson Darach , Gillanders James H. , Heintz Kasper E.
Published: May 2024

Kilonovae (KNe) are one of the fastest types of optical transients known, cooling rapidly in the first few days following their neutron-star merger origin. We show here that KN spectral features go through rapid recombination transitions, with features due to elements in the new ionisation state emerging quickly. Due to time-delay effects of the rapidly expanding KN, a ‘wave’ of these new features passing though the ejecta should be a detectable phenomenon. In particular, isolated line features will emerge as blueshifted absorption features first, gradually evolving into P Cygni features and then pure emission features. In this analysis, we present the evolution of individual exposures of the KN AT2017gfo observed with VLT/X-shooter, which together comprise X-shooter’s first epoch spectrum (1.43 days post-merger). The spectra of these ‘sub-epochs’ show a significant evolution across the roughly one hour of observations, including a decrease in the blackbody temperature and photospheric velocity. The early cooling is even more rapid than that inferred from later photospheric epochs and suggests that a fixed power-law relation between the temperature and time does not describe the data. The cooling constrains the recombination wave, where a Sr II interpretation of the AT2017gfo ∼1 μm feature predicts both a specific timing for the feature emergence and its early spectral shape, including the very weak emission component observed at about 1.43 days. This empirically indicates a strong correspondence between the radiation temperature of the blackbody and the ejecta’s electron temperature. Furthermore, this reverberation analysis suggests that temporal modelling is important for interpreting individual spectra and that higher-cadence spectral series, especially when concentrated at specific times, can provide strong constraints on KN line identifications and the ejecta physics. Given the use of such short-timescale information, we lay out improved observing strategies for future KN monitoring.
Extreme magnetic field modulus variability of the Bp star HD 57372
Authors: Hubrig S. , Chojnowski S. D. , Järvinen S. P. , Ilyin I. , Pan K.
Published: May 2024

Context. In chemically peculiar Ap/Bp stars with large-scale organised magnetic fields of simple centred dipole configuration, the ratio between the maximum and the minimum of the mean magnetic field modulus is on the order of 1.25. Values of two or more are observed only for very few Ap/Bp stars and are indicative of a very unusual magnetic field geometry.

Aims. Determining the magnetic field structure of Ap/Bp stars is bound to provide a different insight into the physics and the origin of the magnetic fields in early-type stars. In this respect, the Bp star HD 57372 is of particular interest because strongly variable magnetically split lines have been observed in HARPS and APOGEE spectra.

Methods. We obtained and analysed measurements of the mean magnetic field modulus and of the mean longitudinal magnetic field using near-infrared spectra and optical polarimetric spectra distributed over the stellar rotation period.

Results. The mean magnetic field modulus 〈B〉 of HD 57372, as estimated from absorption lines that are split via the Zeeman effect and resolved in both optical and near-infrared spectra, is found to vary by an extraordinary amount: about 10 kG. The exceptional value of three for the ratio between the maximum and the minimum of the field modulus is indicative of a very unusual geometry for HD 57372’s magnetic field. All observable quantities were found to vary in phase with the photometric period of 7.889 days. This includes the longitudinal magnetic field 〈Bz〉, which varies from −6 kG up to 1.7 kG in FORS2 spectra, as well as the metal line strengths, whose equivalent widths change by up to 50% of their mean values over the course of the rotation period. The B8 temperature class of HD 57372 also places it among the hottest stars known to exhibit resolved, magnetically split lines.
Large-amplitude transverse MHD waves prevailing in the Hα chromosphere of a solar quiet region revealed by MiHI integrated field spectral observations
Authors: Chae Jongchul , van Noort Michiel , Madjarska Maria S. , Lee Kyeore , Kang Juhyung , Cho Kyuhyoun
Published: May 2024

The investigation of plasma motions in the solar chromosphere is crucial for understanding the transport of mechanical energy from the interior of the Sun to the outer atmosphere and into interplanetary space. We report the finding of large-amplitude oscillatory transverse motions prevailing in the non-spicular Hα chromosphere of a small quiet region near the solar disk center. The observation was carried out on 2018 August 25 with the Microlensed Hyperspectral Imager (MiHI) installed as an extension to the spectrograph at the Swedish Solar Telescope (SST). MiHI produced high-resolution Stokes spectra of the Hα line over a two-dimensional array of points (sampled every 0.066″ on the image plane) every 1.33 s for about 17 min. We extracted the Doppler-shift-insensitive intensity data of the line core by applying a bisector fit to Stoke I line profiles. From our time–distance analysis of the intensity data, we find a variety of transverse motions with velocity amplitudes of up to 40 km s−1 in fan fibrils and tiny filaments. In particular, in the fan fibrils, large-amplitude transverse MHD waves were seen to occur with a mean velocity amplitude of 25 km s−1 and a mean period of 5.8 min, propagating at a speed of 40 km s−1. These waves are nonlinear and display group behavior. We estimate the wave energy flux in the upper chromosphere at 3 × 106 erg cm−2 s−1. Our results contribute to the advancement of our understanding of the properties of transverse MHD waves in the solar chromosphere.
A multi-grain multi-layer astrochemical model with variable desorption energy for surface species
Authors: Kalvāns Juris , Kalniņa Aija , Veitners Kristaps
Published: May 2024

Context. Interstellar surface chemistry is a complex process that occurs in icy layers that have accumulated onto grains of different sizes. The efficiency of the surface processes often depends on the immediate environment of the adsorbed molecules.

Aims. We investigated how gas-grain chemistry changes when the surface molecule binding energy is modified, depending on the properties of the surface.

Methods. In a gas-grain astrochemical model, molecular binding energy gradually changes for three different environments –(1) the bare grain surface, (2) polar water-dominated ices, and (3) weakly polar carbon monoxide-dominated ices. In addition to diffusion, evaporation, and chemical desorption, photodesorption was also made binding energy-dependent, in line with experimental results. These phenomena occur in a collapsing prestellar core model that considers five grain sizes with ices arranged into four layers.

Results. Variable desorption energy moderately affects gas-grain chemistry. Bare-grain effects slow down ice accumulation, while easier diffusion of molecules on weakly polar ices promotes the production of carbon dioxide. Efficient chemical desorption from bare grains significantly delays the appearance of the first ice monolayer.

Conclusions. The combination of multiple aspects of grain surface chemistry creates a gas-ice balance that is different from simpler models. The composition of the interstellar ices is regulated by several binding-energy dependent desorption mechanisms. Their actions overlap in time and space, explaining the similar proportions of major ice components (water and carbon oxides) observed in all directions.
3D printed concrete using Portland pozzolana cement - fly ash based
Authors: Ibrahim A Mohamed , Kumar N Senthil
Published: May 2024

This project investigates the feasibility and properties of 3D printed concrete using Portland Pozzolana Cement (PPC). The increasing demand for construction materials, particularly ordinary Portland cement (OPC), has led to a surge in its usage. Consequently, Portland Pozzolana Cement (PPC) has gained popularity as an alternative due to its advantageous properties. PPC, characterized by its enhanced durability and sustainability, has become a preferred choice in the construction industry, offering versatility and reliability in various construction applications. The main focus of the project is economical printing of concrete structures through 3D printing technology. With sustainability and cost-effectiveness as paramount considerations, the study delves into refining the mix proportions ideal for 3D printing applications. By harnessing the potential of Portland Pozzolana Cement (PPC) with a 35% fly ash content, the aim is to strike a balance between structural integrity, workability, and affordability. It examines various key properties essential for successful 3D printing, such as extrudability, printability, flowability, buildability, setting time and thixotropic open time. Furthermore, the project examines the strength of 3D printed concrete mixes. Through testing and studying these properties, the research aims to contribute to the advancement of eco-friendly and efficient construction practices by using 3D printing and innovative cementitious materials. The findings from this study provide valuable insights to enhance the efficiency of 3D printing and the strength of printed concrete structures, including beams, walls, and other structural elements. By implementing these ideas, potential advancements in construction methodologies could be realized, facilitating more robust and cost-effective building practices. This research aims to contribute to the ongoing evolution of 3D printing technology in construction, ultimately fostering innovation and sustainability in the built environment.
The Current State of Research in the Field of Obtaining Semiconductor Materials and Prospects for Development
Authors: Shukurov D.Kh. , Turaev Kh.Kh. , Kasimov Sh.A. , Jumaeva Z.E. , Muqumova G.J. , Alimnazarov B.Kh. , Ismatov S.Sh.
Published: May 2024

Due to the increase in the world's population and production volumes, the demand for energy is also increasing year by year. The use of solar energy is one of the most effective ways to solve the energy problems of the countries of the world, as well as our Republic. Solar energy is one of the cheap and environmentally friendly resources, and it is important to create cheap and promising solar cells based on inorganic and organic semiconductor materials. Research and development work is being carried out around the world aimed at the creation and production of new solar cells based on semiconductor polymers and phthalocyanine-based dyes. In this regard, solar cells obtained from light-sensitive dyes based on semiconductor polymer materials, metal and non-metal atoms, and phthalocyanine dyes are among the solar cells currently available due to their flexibility, simple design, environmental friendliness and economy. Improving the efficiency of composites based on organic semiconductor compounds, determining their physico-chemical and operational properties, identifying semiconductor polymers and phthalocyanine-based dyes that can replace silicon-based solar panels put into production as solar cells a large-scale research and development work is being carried out on the use of solar elements in the extraction of solar cells.
Spatial Analysis for Better Marketing Decisions with Special Focus on Consumer Behaviour Patterns
Authors: Pavani Pasupuleti , Reddy Komatireddy Sanjay , Teja Yarasuri Venkata , Reddy Police Vivek , Kumar Tanneru Sunil , Habelalmateen Mohammed I.
Published: May 2024

The study explores the pivotal role of Geographic Information Systems (GIS) in shaping marketing decisions, with a special emphasis on consumer behaviour patterns. Distinct studies are scrutinized, spanning diverse applications of GIS in marketing, from spatial consumer behaviour in small towns to the visualization of consumer sales promotions. The analysis encompasses the integration of GIS with methodologies such as spatial point pattern analysis, kernel density estimation, and RFID systems, offering insights into optimal retail site locations, consumer preferences in shopping centers, and the spatial distribution of data. The findings underscore GIS's capacity to enhance decision-making processes, offering a valuable resource for marketers seeking to leverage spatial intelligence for strategic advantage.
Bioconversion of carbon dioxide and zero valent iron to methane by anaerobic sludge: Kinetics and archaeal consortium
Authors: Domrongpokkaphan Vichai , Phalakornkule Chantaraporn , Khemkhao Maneerat
Published: May 2024

Using carbon dioxide (CO2) as a carbon source for renewable energy production has potential applications for CO2 sequestration and greenhouse gas (GHG) emission reduction. In biological conversion, CO2 can be transformed into methane (CH4) by hydrogenotrophic methanogens with hydrogen (H2) as an energy source. In this study, zero-valent iron (ZVI) of 16, 32, 64, and 96 g/L was used as the H2 energy source for a bioconversion of CO2 to CH4. When the ZVI dosage was increased, a decrease in CO2 in the headspace occurred simultaneously with the increase in CH4. The presence of CH4 in both CO2/H2 and CO2/ZVI indicates that hydrogenotrophic methanogens can utilize both ZVI and H2 as electron donors and convert CO2 to CH4. The highest methane yield of 1.728 mmol CH4/mmol CO2 was observed for the CO2/ZVI 96 g/L. The modified Gompertz equation fitted the cumulative CH4 production curves of CO2/H2 and CO2/ZVI very well, where R2 was 0.9915 and 0.9903-0.9968, respectively. 16S rDNA high-throughput sequencing results revealed that ZVI addition facilitated the increase of the family Methanobacteriaceae, which became the most abundant among other archaea. It points out that this family favors ZVI and utilizes electrons more effectively from ZVI than H2.
Management von Vorhofflimmern bei Kardiomyopathien – Rhythmuskontrolle und Antikoagulation
Authors: Deneke Thomas , Kretschmer Elisabeth , Werle Philipp , Bößenecker Peter Arno , Karakur Zeynep , Pauschinger Matthias , Kowalewski Christopher , Brinker-Paschke Andrea
Published: May 2024

Vorhofflimmern (VHF) und Herzinsuffizienz (HI) mit reduzierter Ejektionsfraktion (HFrEF) sind eng miteinander verbundene Erkrankungen, die durch gemeinsame Risikofaktoren und Komorbiditäten charakterisiert sind. Sie beeinflussen sich gegenseitig und verschlechtern die Prognose. Therapeutische Ansätze umfassen die Reduzierung des Schlaganfallrisikos mittels Antikoagulation, Modifikation vorhandener Risikofaktoren sowie frequenz- und rhythmuskontrollierender Maßnahmen.

Bei den meisten HFrEF-Patienten mit VHF ist eine langfristige orale Antikoagulation (OAK) zur Schlaganfallprävention indiziert, wobei der Einsatz von nicht-Vitamin-K-abhängigen oralen Antikoagulanzien (NOAK) sowohl effektiv als auch sicher ist und auch für Patienten mit eingeschränkter LV-Funktion präferiert wird.

Für alle Patienten mit HFrEF und VHF ist eine adäquate frequenzkontrollierende medikamentöse Therapie sinnvoll. Zusätzlich wird bei anhaltenden Beschwerden sowie in bestimmten Fällen eine Rhythmuskontrolle empfohlen. Neuere Studien zeigen, dass die VHF-Ablation im Vergleich zu medikamentösen Ansätzen die Letalität und Herzinsuffizienz-assoziierte Klinikaufenthalte reduziert, funktionelle Parameter verbessert sowie die Lebensqualität steigert, insbesondere bei Patienten mit hoher Erfolgswahrscheinlichkeit der Ablation. Die Auswahl der optimalen Kandidaten für die Ablation sowie der effektivsten Ablationsstrategie bedarf weiterer Forschung.

Bei anderen Kardiomyopathien ohne eingeschränkte LV-Funktion richtet sich die VHF-Behandlungsstrategie nach dem Risikoprofil und der Symptomatik des Patienten. Explizite Daten und Studien fehlen jedoch. Besonders Patienten mit HI mit erhaltener Auswurffraktion (HFpEF) sind häufig stark symptomatisch und profitieren oft von der VHF-Ablation.
Attrition in the First Three Therapy Lines in Patients with Advanced Breast Cancer in the German Real-World PRAEGNANT Registry
Authors: Hartkopf Andreas D. , Walter Christina B. , Kolberg Hans-Christian , Hadji Peyman , Tesch Hans , Fasching Peter A. , Ettl Johannes , Lüftner Diana , Wallwiener Markus , Müller Volkmar , Beckmann Matthias W. , Belleville Erik , Huebner Hanna , Uhrig Sabrina , Goossens Chloë , Link Theresa , Hielscher Carsten , Mundhenke Christoph , Kurbacher Christian , Wuerstlein Rachel , Untch Michael , Janni Wolfgang , Taran Florin-Andrei , Michel Laura L. , Lux Michael P. , Wallwiener Diethelm , Brucker Sara Y. , Fehm Tanja N. , Häberle Lothar , Schneeweiss Andreas
Published: May 2024

Background With more effective therapies for patients with advanced breast cancer (aBC), therapy sequences are becoming increasingly important. However, some patients might drop out of the treatment sequence due to deterioration of their life status. Since little is known about attrition in the real-world setting, this study assessed attrition in the first three therapy lines using a real-world registry.

Methods Patients with information available on the first three therapy lines were selected from the German PRAEGNANT registry (NCT02338167). Attrition was determined for each therapy line using competing risk analyses, with the start of the next therapy line or death as endpoints. Additionally, a simple attrition rate was calculated based on the proportion of patients who completed therapy but did not start the next therapy line.

Results Competitive risk analyses were performed on 3988 1st line, 2651 2nd line and 1866 3rd line patients. The probabilities of not starting the next therapy line within 5 years after initiation of 1st, 2nd and 3rd line therapy were 30%, 24% and 24% respectively. Patients with HER2-positive disease had the highest risk for attrition, while patients with HRpos/HER2neg disease had the lowest risk. Attrition rates remained similar across molecular subgroups in the different therapy lines.

Conclusion Attrition affects a large proportion of patients with aBC, which should be considered when planning novel therapy concepts that specifically address the sequencing of therapies. Taking attrition into account could help understand treatment effects resulting from sequential therapies and might help develop treatment strategies that specifically aim at maintaining quality of life.
Haben Probiotikastämme einen nachweisbaren Stellenwert?
Authors: Früh Jonas
Published: May 2024

Diarrhöen sind in der Reisemedizin die häufigste Infektionskrankheit 1. Reiseassoziierte Diarrhöen sind größtenteils bakteriell bedingt und haben meist einen milden, selbstlimitierenden Verlauf. Dennoch ist die Symptomatik für die Betroffenen häufig subjektiv sehr belastend und führt bei bis knapp der Hälfte der Reisenden zu Reiseplanänderungen 2. Risikofaktoren für das Auftreten einer Reisediarrhö sind Reiseziel und längere Reisedauer, einfache Reisebedingungen und jüngeres Alter 2. Zur Prophylaxe sind eine Reihe an Probiotikastämmen kommerziell erhältlich, jedoch besteht bezüglich einer Schutzwirkung noch wenig Evidenz.
Notfallrettungseinsätze mit Patient*innen mit psychiatrischer oder
psychosozialer Symptomatik: eine Analyse aus Ostniedersachsen
Authors: Noack Eva Maria , Bramesfeld Anke , Schmid Sybille , Schröder Dominik , Müller Frank
Published: May 2024

Ziel der Studie Charakterisierung von Notfallrettungseinsätzen (NFR) mit
Menschen in psychiatrischen oder psychosozialen Krisen. Methodik Analyse
von Notfallprotokollen aus vier Rettungswachen (2019–2020) von NFR mit
Patient*innen zwischen 12 und 65 Jahren. Ergebnisse Bei 23,4% der NFR
zeigten Patient*innen psychiatrische oder psychosoziale Symptome (1,6%
psychotische Symptomatik, 3,0% Suizidalität, 7,1% psychosoziale Krise, 15,7%
Intoxikation). Diese Patient*innen waren im Mittel jünger als Patient*innen mit
anderen Einsatzanlässen. Bei 48,9% lagen zusätzlich somatische Symptome vor. Die
COVID-19-Pandemie hatte nur einen begrenzten Einfluss auf das Auftreten solcher
NFR. Schlussfolgerung Psychiatrische und psychosoziale Einsätze machen
einen bedeutenden Anteil der NFR aus. Dieses Ergebnis legt nahe, dass der Umgang
mit psychiatrischen und psychosozialen Notfällen ein integraler Bestandteil von
Aus- und Weiterbildung von ärztlichem und nichtärztlichem Rettungsfachpersonal
sein sollte.
Spektrum der minimalinvasiven Operationstechniken zur Versorgung von Leistenhernien bei Säuglingen und Kindern
Authors: Markel Moritz , Kahl Fritz , König Tatjana , Ammer Elisabeth , Schmedding Andrea , Sweed Ahmad , Leonhardt Johannes , Muensterer Oliver J.
Published: May 2024

Einer der häufigsten operativen Eingriffe bei Säuglingen und Kindern ist die
Korrektur einer indirekten Leistenhernie. Sie kann sowohl offen als auch mittels
minimalinvasiver Chirurgie (MIC) durchgeführt werden. Seit 1998 wurden dazu
zahlreiche unterschiedliche MIC-Techniken beschrieben. Wissenschaftlich
nachgewiesene Vorteile sind dabei eine kürzere Operationszeit bei beidseitigen
Hernien sowie das geringere Aufkommen einer metachronen kontralateralen Hernie.
Dennoch ist der Anteil von mit MIC versorgten Leistenhernien bei Kindern hierzulande
mit etwa 8% aller Operationen relativ gering. Ziel dieser Synopsis ist die
Beschreibung der verschiedenen MIC-Techniken zur Korrektur der Leistenhernie bei
Kindern, einschl. der jeweiligen Vor- und Nachteile.

Der Videozusammenschnitt zeigt das Spektrum der unterschiedlichen Techniken der
laparoskopischen Leistenhernienversorgung beim Kind. Dazu zählen die intrakorporale
Nahttechnik, die Inzision des Peritoneums, extrakorporale perkutane Techniken sowie
die Kauterisation des offenen Processus vaginalis peritonei beim Mädchen.

Die minimalinvasive Leistenhernienkorrektur beim Kind ist zwar technisch und
wissenschaftlich etabliert, dennoch ist sie noch nicht sehr weit verbreitet. Dieses
Videomanuskript vermittelt Interessierten eine Übersicht der verschiedenen Techniken
und erleichtert damit die klinische Anwendung.
Progress in Photocatalyzed Trifluoromethylthiolation and Trifluoromethylselenolation Reactions
Authors: Li Fei , Song Jia-Wei , Zhang Cheng-Pan , Han Xue
Published: May 2024

The trifluoromethylthio (SCF3) and trifluoromethylselanyl (SeCF3) groups possess high electron-withdrawing ability, excellent lipophilicity, good stability, and bioavailability, and they are promising structural motifs in drug design and development. Photoredox catalysis has clear benefits; it is a mild and sustainable methodology for the modification of chemical structures that enables a variety of chemical reactions that are unattainable using classical ionic chemistry. This review focuses on light-initiated trifluoromethylthiolation and trifluoromethylselenolation reactions with diverse SCF3 and SeCF3 reagents. Representative transformations either using photocatalysts or through EDA complexes, as well as possible reaction mechanisms, are all discussed in this article.

1 Introduction

2 Photocatalyzed Trifluoromethylthiolation

2.1 Photocatalyzed Trifluoromethylthiolation with MSCF3 (M = H, [Me4N], Ag)

2.2 Photocatalyzed Trifluoromethylthiolation with XSCF3 (X = Cl, CF3S)

2.3 Photocatalyzed Trifluoromethylthiolation with ArSO2SCF3

2.4 Photocatalyzed Trifluoromethylthiolation with N–SCF3 Reagents

2.5 Photocatalyzed Trifluoromethylthiolation with Other Reagents

3 Photocatalyzed Trifluoromethylselenolation

3.1 Photocatalyzed Trifluoromethylselenolation with [Me4N][SeCF3]

3.2 Photocatalyzed Trifluoromethylselenolation with ArSO2SeCF3

4 Summary
Design, Synthesis, and Assessment of Tricarboxylic Acid Cycle Probes
Authors: Billingsley Kelvin L. , Chen Joseph , Chao Darrian , Tran Uyen Phuong
Published: May 2024

Hyperpolarized 13C magnetic resonance spectroscopy can provide unique insights into metabolic activity in vivo. Despite the advantages of this technology, certain metabolic pathways such as the tricarboxylic acid (TCA) cycle are more challenging to examine due to the limitations associated with currently available hyperpolarized 13C probes. In this report, we systematically employ computational analyses, synthetic techniques, and in vitro studies to facilitate the design of new chemical probes for the TCA cycle. This platform allows for the rapid identification of probe scaffolds that are amenable to hyperpolarized 13C experimentation. Using these results, we have developed two 13C-labeled chemical probes, [1,4-13C2]-dipropyl succinate and [1,4-13C2]-diallyl succinate, which are employed in hyperpolarized 13C metabolic studies.
Modern Dearomative Enlargement of Heteroaromatic Rings
Authors: Ghiazza Clément , Moreau Xavier
Published: May 2024

Breaking aromaticity by inserting additional atoms within the skeleton of heteroaromatic rings has gained significant attention over the years. As part of the emerging concept of ‘skeletal editing’, this short review retraces the recent progress made on dearomative enlargement reactions of both five- and six-membered heterocycles.

1 Introduction

2 Dearomative Enlargement of Five-Membered Rings

2.1 Pyrroles, Furans, Thiophenes and Their Fused Analogues

2.2 Pyrazoles, Isoxazoles, Isothiazoles and Their Fused Analogues

3 Dearomative Enlargement of Six-Membered Rings

4 Conclusion and Perspectives
Comparative Analysis of Methods of Evaluating Human Fatigue
Authors: de Mello Marco Túlio , Guerreiro Renato de Carvalho , Santarelli Rodrigo , Brant Valdênio Martins , Barreto Amaury Tavares , Silva Flavia Rodrigues da , Silva Andressa
Published: May 2024

The present study used four different methods to estimate fatigue. Forty-seven volunteers (45 men and 2 women), 41.3 ± 7.5 years old, truck operators for 11.5 ± 6.0 years, were included. All participants accepted the invitation to be included in the study. Actigraphy and core temperature were evaluated. The 5-minute psychomotor vigilance test, the Karolinksa Sleepiness Scale (KSS), and the postural assessment using the Light Sonometer™ (Belo Horizonte, Minas Gerais, Brazil) were performed. Fatigue prediction was performed using the Fatigue Avoidance Scheduling Tool (FAST) program. In response to the Pittsburgh Sleep Quality Index (PSQI), 51.06% had good sleep quality and 48.94% had poor sleep quality with an average efficiency of 81.6%. In response to the actigraphy, workers slept an average of 7.2 hours a day with 93.5% efficiency. The workers' core body temperature (CBT) cosinor analysis showed a preserved circadian curve. Core body temperature showed differences between the 6 hours worked in each shift. Similarly, the light sound level meter showed lower risk scores for fatigue in day shifts. Only the variable of the fastest 10% of the Psychomotor Vigilance Test (PVT) showed worse results, while no significant differences were observed by the KSS. The risk analysis by FAST showed a strong influence of the circadian factor. In conclusion, each method has positive and negative points, and it is up to the evaluator/manager to identify the method that best suits the purpose of the evaluation, as well as the local culture and conditions. We recommend using different methods of risk assessment and management in combination with fatigue prediction by Sonometer as well as carrying out assessments, which enable researchers to estimate performance and fatigue throughout the working day, since these may change over the duration of the working day.
Defects of Midbrain/Hindbrain Development: Defects of Anteroposterior and Dorsoventral Patterning
Authors: Biasco Arturo , Dierna Federica , Zanghì Antonio , Vecchio Michele , Falsaperla Raffaele , Praticò Elena R. , Maniaci Antonino , Ruggieri Martino , Polizzi Agata
Published: May 2024

The knowledge regarding the midbrain and the hindbrain (MBHB) malformations has been progressively increased in recent years, thanks to the advent of neuroimaging and genetic technologies. Many classifications have been proposed in order to well describe all of these patterns. The most complete and detailed one is based on the genetic and embryologic features that allow an easier and effective knowledge of these disturbs. It categorizes them into four primary groups: (1) Malformations resulting from early anteroposterior and dorsoventral patterning defects or the misspecification of MBHB germinal zones.(2) Malformations linked to later generalized developmental disorders that notably impact the brain stem and cerebellum, with a pathogenesis that is at least partially comprehended.(3) Localized brain malformations significantly affecting the brain stem and cerebellum, with a pathogenesis that is partly or largely understood, encompassing local proliferation, migration, and axonal guidance.(4) Combined hypoplasia and atrophy observed in presumed prenatal-onset degenerative disorders. Regarding diagnosis, brain stem malformations are typically identified during prenatal assessments, particularly when they are linked with anomalies in the cerebellum and cerebrum. Magnetic resonance imaging is the primary neuroimaging method in the evaluation of these malformations. The clinical characteristics of individuals with malformations in the midbrain or hindbrain are generally nonspecific. Common findings at presentation are hypotonia, motor retardation, ataxia, variable degree of intellectual disability, and abnormal eye movement (e.g., nystagmus, abnormal saccades, oculomotor apraxia, strabismus, and abnormal smooth pursuit). The complexity and the number of these MBHB malformations are constantly increasing. We will provide an overview of MBHB disorders, focusing on embryology, genetic, clinical, and neuroradiology features that could be helpful for clinicians and neuroscientist to understand process of these conditions.
3 Mechanistic Aspects of Transition-Metal-Catalyzed and Non-Transition-Metal-Mediated Cross-Dehydrogenative Coupling
Authors: Logeswaran R. , Aravindan N. , Jeganmohan M.
Published: May 2024

Cross-dehydrogenative coupling (CDC) chemistry is a broad research area that involves the construction of carbon–carbon bonds and carbon–heteroatom bonds by the direct coupling of two C—H bonds or a C—H and an X—H bond. This review provides insights into the mechanisms of such processes, and is organized into methods based on transition-metal catalysis and those mediated by non-transition-metal species.
4 Cross-Dehydrogenative Coupling Involving Alkynes for C(sp2)—C(sp) Bond Formation
Authors: Escudero J. , Besset T.
Published: May 2024

Cross-dehydrogenative coupling reactions represent one of the most environmentally friendly and atom-economic strategies to achieve carbon–carbon or carbon–heteroatom bond formation from non-prefunctionalized substrates, formally producing only dihydrogen as waste. Using terminal alkynes as one of the coupling partners in cross-dehydrogenative couplings, the sustainable synthesis of a myriad of alkynylated compounds is possible. In this review, the major advances in cross-dehydrogenative couplings involving alkynes are covered, with a focus on the formation of C(sp2)—C(sp) bonds, leading to alkynylated arenes, 1,3-enynes, and ynone derivatives. Synthetic strategies, reaction conditions, and the scope of each method are critically discussed, from early developments to date.
10 Alkene/Alkane Cross-Dehydrogenative Coupling for C(sp2)—C(sp3) Bond Formation
Authors: Ali W. , Guin S. , Maiti D.
Published: May 2024

In the area of C—H functionalization, cross-dehydrogenative coupling (CDC) represents the most atom-efficient coupling reaction, since it obviates the need for substrate prefunctionalization. The CDC strategy enables the construction of C—C bonds of diverse hybridization directly from C—H bonds present in the precursors, with formal loss of dihydrogen. C(sp2)—C(sp3) bond formation via selective C(sp3)—H/C(sp2)-H cross coupling is generally difficult to achieve owing to the inertness of C(sp3)-H bonds and their ubiquity in organic molecules. This review describes the different strategies developed over the years in overcoming the aforesaid challenges to enable C(sp2)—C(sp3) bond formation by CDC. Utilization of directing-group-assisted C(sp3)—H metalation with the aid of ligands has largely been the key for selective alkenylation at both proximal and distal positions. Non-directed protocols have also been developed that proceed by selective radical formation using a metal/oxidant combination, or just an oxidant. The developments made in terms of ligand design, scope, mechanistic aspects, and the potential applications of the different methodologies for the CDC between C(sp3)—H and C(sp2)—H bonds are portrayed in this chapter.
18 Heteroatom—Heteroatom Bond Formation through Cross-Dehydrogenative Coupling
Authors: Chen T. , Li C. , Han L.-B.
Published: May 2024

Cross-dehydrogenative coupling between E—H bonds and Z—H bonds, where E and Z are heteroatoms, can be considered as a green approach for the construction of chemical bonds. Since it avoids the need for prefunctionalization of the starting materials, this type of transformation can shorten synthetic routes and increase the total atom efficiency. In this context, such reactions are recognized as an efficient alternative to classical cross-coupling reactions. During the past decades, the cross-dehydrogenative coupling strategy has been widely used for synthesizing various target functional molecules, and great achievements have been made in carbon—carbon bond formation. In recent years, cross-dehydrogenative coupling has also been employed to construct heteroatom—heteroatom bonds; this review covers advances in this field, with a focus on methods for the formation of phosphorus—heteroatom and sulfur—heteroatom bonds
Efficient and consistent adaptive mesh generation for geophysical models: A case study over the Gulf of Thailand
Authors: Chansawang Boobphachard , Zarin Rahat , Humphries Usa Wannasingha , Wongwises Prungchan , Waqas Muhammad , Wangwongchai Angkool
Published: May 2024

Geophysical domains typically exhibit intricate, irregular boundaries characterized by fractal-like geometries, while underlying physical processes operate across a broad spectrum of spatial scales. The challenge lies in generating spatial discretization of these domains that conform to their geographical constraints, utilizing anisotropic, fully adaptive meshes. This problem is compounded by the vast range of scales and a notably heterogeneous parameter space. Current methodologies often rely on ad hoc, model-specific, or application-dependent approaches, which lack comprehensive descriptions. Consequently, the development of new spatial domains is labor-intensive, prone to errors, challenging to replicate, and difficult to maintain consistency due to substantial human involvement. This predicament poses obstacles to the reproducibility of simulations and the establishment of provenance in data handling and model initialization, and it hinders rigorous model intercomparisons. Furthermore, the likelihood of discrepancies in model initialization and forcing parameters increases when employing flexible adaptive meshes. This paper introduces a systematic approach to the automated generation of adaptive meshes for geophysical models. This method is efficient in its generation process and readily reproducible, offering robust and consistent adherence to the source data. The proposed approach facilitates research in complex multi-scale geophysical domains, which would be challenging using existing methods. A simulation of monthly mean currents was carried out as a case study in the Gulf of Thailand. Results revealed that the simulated current circulations agreed with the observation. Examples of its application in various ongoing geophysical modeling endeavors illustrate its effectiveness.
High transparency induced superconductivity in field effect two-dimensional electron gases in undoped InAs/AlGaSb surface quantum wells
Authors: Bergeron E. Annelise , Sfigakis F. , Elbaroudy A. , Jordan A. W. M. , Thompson F. , Nichols George , Shi Y. , Tam Man Chun , Wasilewski Z. R. , Baugh J.
Published: May 2024

We report on transport characteristics of field effect two-dimensional electron gases (2DEGs) in 24 nm wide indium arsenide surface quantum wells. High quality single-subband magnetotransport with clear quantized integer quantum Hall plateaus is observed to filling factor ν = 2 in magnetic fields of up to B = 18 T, at electron densities up to 8 ×1011/cm2. Peak mobility is 11 000 cm2/Vs at 2 ×1012/cm2. Large Rashba spin–orbit coefficients up to 124 meV Å are obtained through weak anti-localization measurements. Proximitized superconductivity is demonstrated in Nb-based superconductor-normal-superconductor (SNS) junctions, yielding 78%–99% interface transparencies from superconducting contacts fabricated ex situ (post-growth), using two commonly used experimental techniques for measuring transparencies. These transparencies are on a par with those reported for epitaxially grown superconductors. These SNS junctions show characteristic voltages IcRn up to 870 μV and critical current densities up to 9.6 μA/μm, among the largest values reported for Nb-InAs SNS devices.
Determination of the electron energy distribution function in weakly ionized plasma by means of a Langmuir probe and numerical methods
Authors: Jauberteau J. L. , Jauberteau I.
Published: May 2024

Numerical methods are used to determine the Electron Energy Distribution Function (EEDF) from I(V) probe characteristics, which are measured using a cylindrical Langmuir probe in the case of weakly ionized plasmas. This task becomes difficult when measurement is complicated by the presence of an external magnetic field or in high pressure plasma because of collision between electrons and heavy particles within the sheath formed around the probe tip. In this case, the electron current must be calculated using the Swift law instead of the Langmuir law. The numerical methods consist of determining the derivative functions of the I(V) probe characteristics in the case of a noisy signal and correcting the EEDF taking into account the electron diffusion coefficient within the sheath formed around the probe collector. Algorithms are given to detail the methods step by step, which can be used to write homemade codes. The methods are tested in the case of different plasma reactors described in the literature, such as microwave plasma and rf (radio-frequency) and dc (direct current) plasma reactors working at different pressures with or without magnetic field. The results show the effect of pressure or magnetic field on the I(V) probe characteristics because of the change in the electron diffusion coefficient.
Field emission characteristics of AlGaN/GaN nanoscale lateral vacuum diodes
Authors: Hernandez Nathaniel , Cahay Marc , O’Mara Jonathan , Ludwick Jonathan , Walker Dennis E. , Back Tyson , Hall Harris
Published: May 2024

We report the design, fabrication, and measurement of the field emission (FE) characteristics of AlGaN/GaN nanoscale lateral vacuum diodes with triangular cathodes and cathode to anode spacings from 50 to 600 nm. The FE characteristics of the AlGaN/GaN diodes with metallic or AlGaN/GaN anodes show successful rectification with forward bias FE current in the range of microamperes or milliamperes, respectively, when biased within a maximum range varying from 10 to 30 V. In the forward bias mode, the measured current Im vs applied anode to cathode bias Vm are well fitted to Murphy–Good profiles associated with FE at higher biases, and an Ohmic leakage profile below the threshold for FE. Our results are the first successful demonstration of FE of electrons between the two two-dimensional electron gases (2DEGs) present on both sides of a nanogap formed by electron lithography through an AlGaN/GaN heterojunction. A qualitative explanation of the loop-type FE characteristics of both AlGaN/GaN vacuum diodes, with either metallic or AlGaN/GaN anodes, is presented.
Optimizing misfit dislocation glide kinetics for enhanced threading dislocation density reduction in Si1−xGex/Si(001) layers through dynamic growth rate control
Authors: Becker L. , Storck P. , Liu Y. , Schwalb G. , Schroeder T. , Fischer I. A. , Albrecht M.
Published: May 2024

Relaxed Si1−xGex layers on Si(001) serve as virtual substrates for strained Si or Ge layers. However, plastically relaxed layers inevitably contain misfit and threading dislocations, negatively affecting devices. Deposition of a SiGe layer on the backside of the substrate introduces a dislocation reservoir at the wafer edge that can reduce the threading dislocation density (TDD) of Si0.98Ge0.02/Si layers, as these preexisting dislocations start gliding toward the wafer center upon reaching the critical thickness. Here, we show that this low-strain system can be used effectively to study dislocation glide kinetics. In agreement with the literature, dislocation glide is a thermally activated process with an activation energy of 2.12–2.16 eV. Near the critical thickness, relaxation is sluggish and inefficient due to the linear dependence of the glide velocity on excess stress. At lower growth rates, dislocations from the edge reservoir are activated in a lower density due to the increase in the critical thickness through partial strain relaxation by already activated dislocations. Contrary to common models, here, the lowest possible growth rate is not essential for minimizing the TDD. Instead, a careful balance between low and high growth rates is beneficial. Overcoming the initial sluggish and inefficient relaxation phase is critical while also avoiding accumulation of strain energy, and, therefore, the activation of dislocation sources. Only in a later stage of buffer growth, the growth rate should be reduced to a minimum. With this method, the TDD of strain relaxed Si0.84Ge0.16 layers is reduced to 7 × 104 cm−2.
Wetting of nanoscale water films on hierarchically structured surfaces
Authors: He Xin , Fan Junshou , Cui Kai , Tian Yuanyuan , Wang Tieying , Wang Shuolin
Published: May 2024

Surfaces with hierarchical structures significantly enhance the hydrophobic properties of solids, proving crucial for diverse applications including self-cleaning, anti-icing, and contamination prevention. In this study, we directly observe the dynamic wetting transitions of nanoscale water films on desirable textured surfaces decorated with dual-scale roughness between various wetting states encompassing Cassie–Cassie, Wenzel–Cassie, Cassie–Wenzel, and Wenzel–Wenzel states. Additionally, detailed information on the wetting of the water film on desirable textured surfaces decorated with dual-scale roughness is obtained using atomistic simulations in conjunction with sampling techniques. Through observation of the dynamic wetting transition, two common types of wetting pathways are directly captured, dubbed the preferential primary intrusion and secondary intrusions. The wetting follows which pathway is dependent on Hs/Ss of the small-scale roughness. The mechanisms behind the wetting transitions are revealed based on corresponding free-energy pathways. Moreover, the effect of aspect ratio and intrinsic contact angle on the wetting behavior has been studied. Subsequently, we construct a wetting phase diagram to exhibit all the possible outcomes and identify different wetting regimes. This work paves the way to understanding the wetting mechanisms on nanoscale textured surfaces with two-tier roughness, which can help to design a hydrophobic surface with superior robustness.