bluuebunny/crossref_metadata_2025_split huggingface dataset:
Der thermische Zerfall von chlorierten Äthylenen in der Gasphase I. Tetrachloräthylen und Trichloräthylen
Authors: Zabel F. 
Published: October 2023

AbstractDer thermische Zerfall von Trichloräthylen und Tetrachloräthylen wurde im Temperaturbereich zwischen 1450K und 1900K und bei Drücken von 2 bis 175 atm in sehr stark verdünnten Gemischen mit Argon als Trägergas hinter reflektierten Stoßwellen untersucht. C2Cl4 und sehr wahrscheinlich auch C2HCl3 zerfallen unter Abspaltung eines Chloratoms. Aus der Druckabhängigkeit der Geschwindigkeits‐konstanten 1. Ordnung erhält man unter Anwendung von Theorien unimolekularer Reaktionen für die beiden Grenzbereiche sehr niedriger und sehr hoher Drücke die Arrhenius‐Ausdrücke:
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Mögliche Folgereaktionen, insbesondere die Bedeutung von halogenierten Acetylenen, werden diskutiert.
Solvent Nuclear Magnetic Relaxation in Polyacid Solutions
Authors: Klink J. J. V. D. , Schriever J. , Leyte J. 
Published: October 2023

AbstractExchange of solvent protons or deuterons with acid groups in aqueous polyacid solutions may influence the observed proton and deuteron relaxation rates quite differently. It is shown that in the case of poly(acrylic acid) solutions of approx. 0.3 N, the deuteron relaxation rate is dominated by relaxation in polyacid groups and does not give information on the behaviour of hydrated water molecules
Der Mechanismus der Komplexbildung in polaren Lösungsmitteln. Zusammenhang zwischen der Bildungs‐ und Dissoziationsgeschwindigkeit mit der Donizität des Lösungsmittels
Authors: Dickert F. , Hoffmann H. , Janjic T. 
Published: October 2023

AbstractMit Hilfe von Relaxationsverfahren wurde die Kinetik der Bildung und Dissoziation von Ni(SCN)2‐Komplexen in den Lösungsmitteln H2O, DMSO, DMF, CH3OH und CH3 · CN untersucht. In allen nichtwäßrigen Lösungsmitteln konnten immer zwei Relaxationszeiten beobachtet werden, die auf den Mono‐ und Bis‐Komplex zurückgeführt werden konnten. Die Bildungs‐ und Dissoziationsgeschwindigkeiten der Komplexe und die zugehörigen Aktivierungsparameter wurden ermittelt. Es zeigte sich, daß sich sowohl die Gleichgewichts‐ als auch die Geschwindigkeitskonstanten mit der Polarität der Lösungsmittel korrelieren lassen, wenn als Polaritätsskala die von V. Gutmann eingeführte Donizität verwendet wurde. Auch die Austauschgeschwindigkeiten lassen sich mit Hilfe der Donizität verständlich machen.
Entwicklungen und Tendenzen in der Photoelektronenspektroskopie
Authors: Hohlneicher G. 
Published: October 2023

AbstractIm vorliegenden Beitrag wird versucht, einen Überblick über einige neuere Entwicklungen der Photoelektronenspektroskopie zu geben. Dem Motto der diesjährigen Hauptversammlung entsprechend, stehen dabei solche Anwendungen im Vordergrund, bei denen die Photoelektronenspektroskopie zur Untersuchung molekularer Eigenschaften herangezogen wird.
Fortschritte der Schwingungsspektroskopie: Verbesserung der experimentellen Technik und Verfahren zur Strukturaufklärung durch Berechnung der Frequenzen, Infrarot‐ und Raman‐Intensitäten
Authors: Schrader B. 
Published: October 2023

AbstractDie Infrarot‐ und Ramanspektrometer sind heute derart entwickelt, daß es nicht mehr schwierig ist, die vollständigen Spektren im Bereich 20 … 4000 cm−1aufzunehmen. Dank der Entwicklung der Laserlichtquellen, von Interferometern und der Anwendung der elektronischen Datenverarbeitung wurde der Anwendungsbereich dieser Methoden wesentlich erweitert: Analysen, selbst unter extremen Bedingungen (bei geringer Substanzmenge oder niedriger Konzentration, Fernanalysen und die Untersuchung schneller Reaktionen), sind heute zuverlässiger und schneller möglich, und neue Techniken wurden erschlossen. Besonders reizvoll erscheinen die Fortschritte bei der Berechnung der Frequenzen und Intensitäten der Spektren, so daß man diese Methoden bei Fragen nach der Struktur von Verbindungen, insbesondere nach dem räumlichen Bau, besser anwenden kann.
Herzberg‐Teller‐Kopplung zweiter Ordnung in Schweratomaromaten
Authors: Friedrich J. , Metz F. , Dörr F. 
Published: October 2023

AbstractMit Hilfe der Polarisationsgrad‐Spektroskopie werden die verschiedenen Zerfallsprozesse aus den Subzuständen des niedrigsten Tripletts von Monohalogennaphthalinen untersucht. Es zeigt sich, daß die Schweratomsubstitution die Zerfallsraten aus dem z‐Zustand (z senkrecht zur Molekülebene) wesenthch starker beeinflußt als die der beiden anderen Spinzustände. Eine befriedigende Erklärung dieser Beobachtung ist über eine Herzberg‐Teller‐(HT)‐Kopplung zweiter Ordnung möglich. Konsequenzen im Hinblick auf einen d‐Isotopeneffekt in der 00‐Rate der Phosphoreszenz werden diskutiert.
Isobare, gasvolumetrische Bestimmung der Reaktionskinetik von Äthanolaminen mit Äthylenoxid in Wasser
Authors: Gestrich W. , Krauss W. 
Published: October 2023

AbstractIn einer halbautomatischen Apparatur (Abb. 1) wurden im Bereich zwischen etwa 200 und 700 Torr Äthylenoxidpartialdruck bei 20, 40 und 60°C die Löslichkeiten des Äthylenoxids in Wasser, sowie die Umsetzungsgeschwindigkeiten mit Mono‐, Di‐ und Triäthanolamin unter Berücksichtigung der Glykolbildung isobar über die Volumenverkleinerung des Gasraumes bestimmt. Jeder Einzelschritt der Reaktionsfolge erwies sich bis zu Umsätzen von 80–90% als streng partiell erster Ordnung bezüglich Äthylenoxid und der Aminkomponente. Der simultane Äthylenoxidverbrauch durch Folgeschritte und durch die Hydratation wurde durch iterative Variation der jeweils zu bestimmenden Geschwindigkeitskonstante rechnerisch ermittelt. Die Temperaturabhängigkeiten der Geschwindigkeitskonstanten folgen exakt dem Arrheniusansatz.
Process Variables in Electro‐Organic Synthesis, III. Electrosorption and Mass‐Transfer as Dominating Factors in the Anodic Styrene Oxidation
Authors: Plzak V. , Schneider H. , Wendt H. 
Published: October 2023

AbstractStyrene – like many other asymmetric olefins [2] – undergoes anodic oxidation to monomeric and dimeric products. The formation for both products starts with the generation of a very reactive radical cation which either solvolyzes to form the monomer or adds to the double bond of unoxidized styrene to form the dimer.Both reactions are so fast, that they proceed at the anode surface. Thus it is the surface concentration of the reactants (solvent and styrene, resp.) which governs the relative rates of the solvolysis and the addition reaction and determine the product composition. It is the styrene surface concentration which is most effectively influenced by the adsorption equilibria on different anode materials (C, Fe3O4 PbO2, Pt) and the mass transport conditions (governed by cstyr, and i/id). It is thus possible to optimize the styrene oxidation towards either monomer or dimer formation at will.
Prophylactic use of cardiac medications for delay of left ventricular dysfunction in Duchenne muscular dystrophy
Authors: Conway Kristin M. , Thomas Shiny , Ciafaloni Emma , Khan Rabia S. , Mann Joshua R. , Romitti Paul A. , Mathews Katherine D. ,   the Muscular Dystrophy Surveillance, Tracking and Research Network (MD STARnet)
Published: October 2023

AbstractBackgroundEpidemiological support for prophylactic treatment of left ventricular dysfunction (LVD) in Duchenne muscular dystrophy is limited. We used retrospective, population‐based surveillance data from the Muscular Dystrophy Surveillance, Tracking and Research Network to evaluate whether prophylaxis delays LVD onset.MethodsWe analyzed 455 males born during 1982–2009. Age at first abnormal echocardiogram (ejection fraction <55% or shortening fraction <28%) determined LVD onset. Prophylaxis was defined as cardiac medication use at least 1 year prior to LVD. Corticosteroid use was also coded. Kaplan–Meier curve estimation and Cox Proportional Hazard modeling with time‐varying covariates describe associations.ResultsLVD was identified among 40.7%; average onset age was 14.2 years. Prophylaxis was identified for 20.2% and corticosteroids for 57.4%. Prophylaxis showed delayed LVD onset (p < .001) and lower hazard of dysfunction (adjusted hazard ratio [aHR] = 0.39, 95%CL = 0.22, 0.65) compared to untreated. Compared to no treatment, continuous corticosteroids only (aHR = 1.01, 95%CL = 0.66, 1.53) and prophylaxis only (aHR = 0.67, 95%CL = 0.25, 1.50) were not cardioprotective, but prophylaxis plus continuous corticosteroids were associated with lower hazard of dysfunction (aHR = 0.37, 95%CL = 0.15, 0.80).ConclusionsProactive cardiac treatment and monitoring are critical aspects of managing Duchenne muscular dystrophy. Consistent with clinical care guidelines, this study supports clinical benefit from cardiac medications initiated prior to documented LVD and suggests further benefit when combined with corticosteroids.
Online case‐based learning for medical students as a teaching method for biochemistry at King Abdulaziz University amid COVID‐19 pandemic (a study conducted in 2021)
Authors: Kubbara Eman A. , Ahmed Nasreldin Marhoum , Alamri Turki , Bakarman Marwan A. , Malibary Husam , Eid Rasha , Alzahrani Abdulrahman Omer 
Published: October 2023

AbstractOnline case‐based learning (CBL) is a method used by King Abdulaziz University to teach medical students in their preclinical years. The use of CBL in basic sciences is important for enabling medical students to correlate basic sciences with future clinical practice. This study implemented online CBL for biochemistry teaching as part of the medical genetic module for 3rd‐year preclinical students. Teaching during the study was completely online because of restricted precautions caused by the COVID‐19 pandemic, except for practical sessions that were held on campus. The case was presented to the students involved in prenatal screening and diagnosis. Students were guided to learn and discuss the biochemical tests used for prenatal screening and diagnosis and their clinical importance. They were divided into two groups: the control group was given an online lecture and the intervention group was given an online CBL session before the lecture. The online lecture was given to both groups simultaneously by the same instructor, and then 10 MCQs tests were distributed to both groups after the lecture, and their test scores were compared. A 10‐question survey was administered to the intervention group to assess their perception of the online CBL session after the test. A significant difference was found between the intervention and control groups regarding test scores (p < 0.001), and most students found the online CBL session enjoyable and motivating.
CD146 promotes malignant progression of breast phyllodes tumor through suppressing DCBLD2 degradation and activating the AKT pathway
Authors: Chen Jiewen , Xu Qingji , Liu Dan , Li Xun , Guo Mingyan , Chen Xuehui , Liao Jianyou , Lei Rong , Li Wende , Huang Hongyan , Saw Phei Er , Song Erwei , Yan Xiyun , Nie Yan 
Published: October 2023

AbstractBackgroundAs a rapid‐progressing tumor, breast malignant phyllodes tumors (PTs) are challenged by the lack of effective therapeutic strategies and suitable prognostic markers. This study aimed to clarify the role and mechanism of CD146 on promoting PTs malignant progression, and to identify a novel prognosis marker and treatment target of breast malignant PTs.MethodsThe expression and prognostic significance of CD146 in PTs was detected through single‐cell RNA‐sequencing (scRNA‐seq), immunostaining, real‐time PCR and other methodologies. Functional experiments including proliferation assay, colony formation assay, transwell assay, and collagen contraction assay were conducted to validate the role of CD146 in malignant progression of PTs. The efficacy of anti‐CD146 monoclonal antibody AA98 against malignant PTs was corroborated by a malignant PT organoid model and a PT patient‐derived xenograft (PDX) model. Transcriptome sequencing, proteomic analysis, co‐immunoprecipitation, and pull‐down assay was employed to identify the modulating pathway and additional molecular mechanism.ResultsIn this study, the scRNA‐seq analysis of PTs disclosed a CD146‐positive characteristic in the α‐SMA+ fibroblast subset. Furthermore, a progressive elevation in the level of CD146 was observed with the malignant progression of PTs. More importantly, CD146 was found to serve as an independent predictor for recurrence in PT patients. Furthermore, CD146 was found to augment the viability and invasion of PTs. Mechanistically, CD146 acted as a protective “shield” to prevent the degradation of Discoidin, CUB, and LCCL domain‐containing protein 2 (DCBLD2), thereby activating the phosphoinositide 3‐kinase (PI3K)/protein kinase B (AKT) signaling pathway and enhancing malignant behaviors of PT cells. In the malignant PT organoid and PDX model, a significant suppression of malignant PT growth was observed after the application of AA98.ConclusionsThese findings suggested that CD146 served as an efficacious marker for predicting PT malignant progression and showed promise as a prognosis marker and treatment target of breast malignant PTs. The study further unveiled the essential role of the CD146‐DCBLD2/PI3K/AKT axis in the malignant progression of PTs.
A Hydride Migration Mechanism for the Mo‐CatalyzedZ‐2‐Selective Isomerization of Terminal Alkenes
Authors: Jenny Sarah E. , Serviano Juan M. , Nova Ainara , Dobereiner Graham E. 
Published: October 2023

AbstractThe catalytic one‐bond isomerization (transposition) of 1‐alkenes is an emerging approach toZ‐2‐alkenes. Design of more selective catalysts would benefit from a mechanistic understanding of factors controllingZselectivity. We propose here a reaction pathway forcis‐Mo(CO)4(PCy3)(piperidine) (3), a precatalyst that shows highZselectivity for transposition of alpha olefins (e. g., 1‐octene to 2‐octene, 18 : 1Z : Eat 74 % conversion). Computational modeling of reaction pathways and isotopic labeling suggests the isomerization takes place via an allyl (1,3‐hydride shift) pathway, where oxidative addition offac‐(CO)3Mo(PCy3)(η2‐alkene) is followed by hydride migration from one position (cisto allyl C3carbon) to another (cisto allyl C1carbon) via hydride/CO exchanges. Calculated barriers for the hydride migration pathway are lower than explored alternative mechanisms (e. g., change of allyl hapticity, allyl rotation). To our knowledge, this is the first study to propose such a hydride migration in alkene isomerization.
Functionalized Thiophosphate and Oxidic Filler Particles for Hybrid Solid Electrolytes
Authors: Helmers Laura , Frankenberg Finn , Brokmann Julian , Burmeister Christine , Buchheit Annika , Kwade Arno , Michalowski Peter 
Published: October 2023

AbstractTo achieve the commercialization of solid‐state‐batteries (SSBs), solid electrolyte properties need to be further improved. The hybrid solid electrolyte (HSE) approach is expected to combine the favorable properties of different solid electrolyte classes and is therefore systematically investigated. Mixing low amounts of thiophosphate or oxide filler particles (FP) into a polyethylene oxide (PEO) polyethylene glycol (PEG) and lithium salt bis(trifluoromethane)sulfonimide (LiTFSI) matrix cannot improve the electrochemical properties. Silanization of the thiophosphate FPs significantly increases the ionic conductivity to 0.1 mS cm−1 at room temperature compared to 0.017 mS cm−1 for a pure PEO solid electrolyte. Moreover, a correlation between the intrinsic conductivity of the FPs and the resulting conductivity of the HSE is observed. Also, the functionalization is successfully transferred to oxide FPs. In addition to an equally significant increase in ionic conductivity, a strong influence of the crystallite size of the FPs on the resulting ionic conductivity of the HSE was found. The discovered effect of FP surface structure on overall HSE conductivity indicates a participation of the FP surface in ion transport and emphasizes the need for tailored filler design in HSE applications.
Molecular‐derived risk of malignancy and the related positive call rate of indeterminate thyroid cytology diagnoses as quality metrics for individual cytopathologists
Authors: Ohori N. Paul , Cuda Jacqueline M. , Bastacky Sheldon I. , Yip Linwah , Karslioglu‐French Esra , Morariu Elena M. , Ullal Jagdeesh , Ramonell Kimberly M. , Carty Sally E. , Nikiforov Yuri E. , Schoedel Karen E. , Seethala Raja R. 
Published: October 2023

AbstractBackgroundIndeterminate thyroid cytopathology diagnoses represent differing degrees of risk that are corroborated by follow‐up studies. However, traditional cytologic–histologic correlation may overestimate the risk of malignancy (ROM) because only a subset of cases undergo resection. Alternatively, some molecular tests provide probability of malignancy data to calculate the molecular‐derived risk of malignancy (MDROM) and the positive call rate (PCR). The authors investigated MDROMs and PCRs of indeterminate diagnoses for individual cytopathologists as quality metrics.MethodsThis study was approved by the Department of Pathology Quality Improvement Program. Thyroid cytopathology diagnoses and ThyroSeq v3 results were retrieved for each cytopathologist for a 2‐year period with at least 3 years of follow‐up for the atypia of undetermined significance (AUS), follicular neoplasia (FN), and follicular neoplasia, oncocytic‐type (ONC) cytopathologic diagnoses. MDROMs and PCRs were compared with reference ROMs and cytologic–histologic correlation outcomes.ResultsThe overall MDROMs (and ranges for cytopathologists) for the AUS, FN, and ONC categories were 13.4% (range, 5.8%–20.8%), 28.1% (range, 22.1%–36.7%), and 27.0% (range, 19.5%–41.5%), respectively, and most individual cytopathologists' MDROMs were within reference ROM ranges. However, PCRs more effectively parsed the differences in cytopathologists' ROM performance. Although the overall PCRs were not significantly different across cytopathologists (p = .06), the AUS PCRs were quite different (p = .002). By cytologic–histologic correlation, six of 55 resected cases (10.9%) were falsely negative, and there were no false‐positive cases.ConclusionsMDROMs and PCRs evaluate concordance with reference ROMs and with one another and provide individual feedback, which potentially facilitates quality improvement.
Assessment and management of diabetes‐related foot infection according to the new International Working Group on the Diabetic Foot guidelines 2023—Multidisciplinary grand rounds
Authors: Hon Kay , Nobels Frank , Senneville Éric , Uckay Ilker , Maas Mario , Fitridge Robert 
Published: October 2023

AbstractDiabetes‐related foot disease is a serious and common complication for people with diabetes mellitus. The gold standard care for a person with diabetes‐related foot disease is the involvement of a multidisciplinary foot team engaged in evidence‐based care. To date, there are seven International Working Group on the Diabetic Foot (IWGDF) guidelines published to assist healthcare providers in managing diabetes‐related foot disease around the world. This review discusses the acute management of diabetes‐related foot infection with insights from experts of various specialities (internal medicine, infectious disease, vascular surgery, radiology) with a discussion on the implementation of IWGDF guidelines in real life practice and the challenges that healthcare providers may face.
Distribution patterns of Quercus ilex from the last interglacial period to the future by ecological niche modeling
Authors: Suicmez Burak , Avci Meral 
Published: October 2023

AbstractThe plants' geographic distribution is affected by natural or human‐induced climate change. Numerous studies at both the global and regional levels currently focus on the potential changes in plant distribution areas. Ecological niche modeling can help predict the likely distribution of species according to environmental variables under different climate scenarios. In this study, we predicted the potential geographic distributions of Quercus ilex L. (holm oak), a keystone species of the Mediterranean ecosystem, for the Last Interglacial period (LIG: ~130 Ka), the Last Glacial Maximum (LGM: ~22 Ka), mid‐Holocene (MH: ~6 Ka), and future climate scenarios (Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios) for 2050–2070 obtained from CCSM4 and MIROC‐ESM global climate scenarios respectively. The models were produced with algorithms from the R‐package “biomod2” and assessed by AUC of the receiver operating characteristic plot and true skill statistics. Aside from BIOCLIM (SRE), all model algorithms performed similarly and produced projections that are supported by good evaluation scores, although random forest (RF) slightly outperformed all the others. Additionally, distribution maps generated for the past period were validated through a comparison with pollen data acquired from the Neotoma Pollen Database. The results revealed that southern areas of the Mediterranean Basin, particularly coastal regions, served as long‐term refugia for Q. ilex, which was supported by fossil pollen data. Furthermore, the models suggest long‐term refugia role for Anatolia and we argue that Anatolia may have served as a founding population for the species. Future climate scenarios indicated that Q. ilex distribution varied by region, with some areas experiencing range contractions and others range expands. This study provides significant insights into the vulnerability of the Q. ilex to future climate change in the Mediterranean ecosystem and highlights the crucial role of Anatolia in the species' historical distribution.
A landmark‐free analysis of the pelvic girdle in Sulawesi ricefishes (Adrianichthyidae): How 2D and 3D geometric morphometrics can complement each other in the analysis of a complex structure
Authors: Spanke Tobias , Gabelaia Mariam , Flury Jana M. , Hilgers Leon , Wantania Letha Louisiana , Misof Bernhard , Wipfler Benjamin , Wowor Daisy , Mokodongan Daniel F. , Herder Fabian , Schwarzer Julia 
Published: October 2023

AbstractGeometric morphometrics (GM) enable the quantification of morphological variation on various scales. Recent technical advances allow analyzing complex three‐dimensional shapes also in cases where landmark‐based approaches are not appropriate. Pelvic girdle bones (basipterygia) of Sulawesi ricefishes are 3D structures that challenge traditional morphometrics. We hypothesize that the pelvic girdle of ricefishes experienced sex‐biased selection pressures in species where females provide brood care by carrying fertilized eggs supported by elongated pelvic fins (“pelvic brooding”). We test this by comparing pelvic bone shapes of both sexes in species exhibiting pelvic brooding and the more common reproductive strategy “transfer brooding,” by using landmark‐free 2D and 3D GM, as well as qualitative shape descriptions. Both landmark‐free approaches revealed significant interspecific pelvic bone variation in the lateral process, medial facing side of the pelvic bone, and overall external and internal wing shape. Within pelvic brooders, the three analyzed species are clearly distinct, while pelvic bones of the genus Adrianichthys are more similar to transfer brooding Oryzias. Female pelvic brooding Oryzias exhibit prominent, medially pointing tips extending from the internal wing and basipterygial plate that are reduced or absent in conspecific males, Adrianichthys and transfer brooding Oryzias, supporting our hypothesis that selection pressures affecting pelvic girdle shape are sex‐biased in Sulawesi ricefishes. Furthermore, both sexes of pelvic brooding Oryzias have overall larger pelvic bones than other investigated ricefishes. Based on these differences, we characterized two reproductive strategy‐ and sex‐dependent pelvic girdle types for Sulawesi ricefishes. Morphological differences between the investigated pelvic brooding genera Adrianichthys and Oryzias provide additional evidence for two independent origins of pelvic brooding. Overall, our findings add to a better understanding on traits related to pelvic brooding in ricefishes and provide a basis for upcoming studies on pelvic girdle function and morphology.