bluuebunny/crossref_metadata_2025_split huggingface dataset:
Löslichkeit von Chlorwasserstoff in organischen Verbindungen. Die relative Stärke der basischen Eigenschaften von aromatischen Verbindungen und Äthern
Authors: Strohmeier Walter , Echte A. 
Published: October 2023

AbstractEs wurde die Löslichkeit von Chlorwasserstoff in Lösungen von Tetrachlorkohlenstoff, Äthylnitrat, Diphenyläther, Nitrobenzol, o‐Nitrotoluol, Anisol, β,β'‐Dichloräthyläthor, Dioxan, n‐Butyläther, Dibenzyläther, n‐Propyläther, Diäthyläther, Tetrahydropyran und Tetrahydrofuran in Heptan bei den Temperaturen T = 200,8°; 209,6°; 220,3°; 230,8°; 241,6°; 258,4° und 272,9°K untersucht. Für die Temperaturen T = 272,9°K wurde die Henry‐Konstante für den Molenbruch xHCl → 0 bestimmt.Die Henry‐Konstante kann als relatives Maß für die Stärke der basischen Eigenschaften der Verbindungen genommen werden1).Innerhalb des gemessenen Temperaturintervalls ist die relative Abstufung der Basenstärke der untersuchten Verbindungen unabhängig von der Temperatur.Es wird eine Übersicht über die verschiedenen Methoden zur Messung der Basenstärke von aromatischen Verbindungen und Äthern gegeben und die bisherigen experimentellen Ergebnisse in einer Tabelle zusammengefaßt. Die verschiedenen Methoden ergeben eine ausgezeichnete Übereinstimmung. Einzelne Abweichungen werden diskutiert.
Zur Deutung der Passivität, insbesondere der Flade‐Bezugsspannung des Eisens
Authors: Göhr H. , Lange E. 
Published: October 2023

AbstractUnter Verwendung chemisch‐thermodynamischer Daten für Eisen und Eisenoxyde wird das Verhalten des aktiven Eisens und sein Übergang in den passiven Zustand gedeutet.Dabei wird ausgegangen von einer durch teilanodische Polarisation nach

zunächst erzeugten Fe3O4‐Schicht mit dem Ergebnis einer aktiven Eisenelektrode 2. Art. Beim Erreichen einer bestimmten Bezugsspannung der aus der Versuchselektrode und der n‐H‐Elektrode bestehenden Bezugszelle kommt es unter oberflächlicher Oxydation des Fe3O4 nach

zu einer kristallographisch dem Fe3O4 ähnlichen und daher gut deckenden, passivierenden γ‐Fe2O3‐Schicht. Dieser UH‐Wert ist die bekannte Flade‐Bezugsspannung.Dieses Bild erklärt die Kleinheit der Korrosionsgeschwindigkeit des passiven Eisens, ihre Unabhängigkeit von der Fe+3‐Konzentration, ihr Ansteigen mit cH+ und ihre Unabhängigkeit von der Rührung und vom UH in einem Bereich oberhalb der Flade‐Bezugsspannung.
Kollektivparamagnetismus und Volumen magnetisierter Aerosole
Authors: Knappwost A. 
Published: October 2023

AbstractDas Verfahren der magnetischen Teilchengrößenbestimmung mit Hilfe der Langevinschen Theorie für kollektivparamagnetische Partikel wird auf die früher von Haul und Schoon hergestellten γ‐Fe2O3‐Aerosole angewandt, deren Ausdehnung von den Autoren elektronographisch zu 30–40 Å gefunden wurde. Nach Ermittlung der spontanen Magnetisierung des γ‐Fe2O3 mittels einer Variante der Felddifferenzenmethode und nach Anwendung eines Iterationsverfahrens zur Berücksichtigung der Teilchengrößenabhängigkeit der spontanen Magnetisierung wird die Ausdehnung der Bereiche zu 27 Å gefunden und gezeigt, daß die magnetochemische Methode richtige Werte liefert und zu weiteren Aussagen fähig ist. Die Feldstäkeabhängigkeit der Suszeptibilität der Aerosole, deren Ursache im einzelnen diskutiert wird die aber nach Berechnung des Argumentbetrages der Langevin‐Funktion aus dem Volumen der Bereiche bei den niederen Meßfeldstärken von etwa 5000 Oe nicht auftreten dürfte, weist auf eine erhebliche Breite der Größenverteilungskurve der Aerosole hin. Es wird ferner dargelegt, daß die Feldstärkeabhängigkeit der Suszeptibilität kein Kriterium für das Einsetzen der spontanen Magnetisierung ist, die schon in kleineren Teilchen als solchen von 30 Å Ausdehnung vorliegen dürfte.
Über die Kette: Pt, H2 (1 atm)/HCl, Hg2Cl2(s)/Hg in organischen Lösungsmitteln und ihren Gemischen mit Wasser IV. Pt, H2(l atm)/HCl(m), Äthanol(x), H2O(100‐x), Hg2Cl2(s)/Hg
Authors: Schwabe K. , Kunz M. 
Published: October 2023

AbstractMit der Kette Pt,H2(l atm)/HCl(m), Äthanol(x),H2O(100‐x),Hg2Cl2(s)/Hg wurden bei verschiedenen Gehalten an Äthanol und Salzsäure EMK‐Messungen durchgeführt. Nach dem Extrapolationsverfahren von McLimes und Brown wurden Standardpotentiale, Aktivitätskoeffizienten und Mediumeffekte ermittelt.
Infrarotspektroskopische Untersuchungen an isotopen Stickstoff‐Verbindungen 2. Mitteilung: Das Schwingungsspektrum des Benzamids
Authors: Weckherlin S. , Lottke W. 
Published: October 2023

AbstractDas Schwingungsspektrum des Benzamids wird mit Hilfe seines 16N‐Isotopisomeren analysiert. Dabei werden die Ergebnisse der Messungen an deuterierten Säureamiden bestätigt, außerdem ergibt sich ein direktes experimentelles Argument für die Kopplung der Amid I‐, II‐ und III‐Bande. Die Lage der ebenen Pendelschwingung der NH2‐Gruppe kann bei 1124 cm−1 lokalisiert werden.
Efficacy and safety of immune checkpoint inhibitors in recurrent or metastatic head and neck squamous cell carcinoma: A systematic review and meta‐analysis of randomized clinical trials
Authors: Dang Shoutao , Zhang Shurong , Zhao Jingyang , Li Xinyu , Li Wei 
Published: October 2023

AbstractBackgroundImmune checkpoint inhibitors (ICIs) showed antitumor activity for recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, the results from different studies were controversial.MethodsOnline databases were searched for randomized clinical trials (RCTs) evaluating ICIs for R/M HNSCC. The characteristics of the studies and the results of overall survival (OS), progression‐free survival (PFS), objective response rate (ORR), treatment‐related adverse events (TRAEs) were extracted.ResultsA total of 4936 patients from eight studies were included. Anti‐PD1/PDL1 monotherapy significantly improved OS in total population (hazard ratio, HR, 0.87, 95% CI, 0.79–0.95, p = 0.003) and PD‐L1 high expression patients (HR, 0.71, 95% CI, 0.55–0.90, p = 0.006) with significant lower incidence of any grade TRAEs (odds ratio, OR, 0.16, 95% CI, 0.07–0.37, p < 0.00001) and Grades 3–5 TRAEs (OR, 0.18, 95% CI, 0.10–0.33, p < 0.0001) compared with standard of care (SOC); however, the pooled results of PFS and ORR were not significant different. PD1/PDL1 inhibitors plus CTLA4 inhibitors did not improve OS, PFS, ORR compared with SOC or ICIs monotherapy; however, the incidence of Grades 3–5 TRAEs was significant higher compared with ICIs monotherapy (OR, 1.80, 95% CI, 1.34–2.41, p = 0.0001).ConclusionsAnti‐PD1/PDL1 monotherapy could improve OS for R/M HNSCC with significant lower incidence of TRAEs compared with SOC. PD1/PDL1 inhibitors plus CTLA4 inhibitors showed no more benefit compared with both SOC and ICIs monotherapy, but the incidence of Grades 3–5 TRAEs was significant higher compared with ICIs monotherapy.
Dense NiCo2O4 Nanoneedles Grown on Carbon Foam Showing Excellent Electrochemical and Microwave Absorption Properties
Authors: Wu Sutang , Zhu Yihan , Yan Xuehua , Zhang Wenjing , Zhang Mengyang , Huang Xinpeng , Pan Jianmei , Shahnavaz Zohreh , Mohammadi Moradian Jamile 
Published: October 2023

AbstractElectromagnetic pollution could harm sensitive electronic equipment due to the rising use of electronic devices and communication infrastructure. The supercapacitor‘s electrochemical performance should be enhanced, and electromagnetic damage should be prevented. This study proposes NiCo2O4/CF composites for supercapacitors and microwave absorption. They are made by combining hydrothermal and annealing processes. Dense NiCo2O4 nanoneedles were uniformly grown on the outer layer of carbon foam (CF) as a growth skeleton, preventing the agglomeration of NiCo2O4. The composite had a specific capacitance of 537.5 F/g at 1 A/g. When the current density was set to 1 A/g, the supercapacitor that used NiCo2O4/CF as the cathode had a specific capacitance of 70.7 F/g, and when the current density was increased to 10 A/g, the original specific capacitance of 87.2 % could still be maintained after 5000 charge‐discharge cycles. At a power density of 3695.5 W/kg, an energy density of 22.1 Wh/kg could be maintained. Furthermore, we performed a microwave absorption test and determined its reflection loss curve for various sample thicknesses. Recombination enhanced the composite material‘s microwave absorption capability by greatly reducing the dielectric loss and the magnetic loss.
Bimetallic Manganese Catalysts: A Route to Controlled and Switchable Polymerization of Lactones
Authors: Li Bokun , Hu Chenyang , Yang Zhenjie , Pang Xuan , Chen Xuesi 
Published: October 2023

AbstractThe sustainable solution to the environmental problem of polymeric materials calls for efficient and well‐controlled ring‐opening polymerization catalytic systems. Inspired by the highly reactive and stereospecific bimetallic catalysts, three kinds of bimetallic Salen‐Mn catalysts supported by biaryl linking moieties are synthesized and applied to polymerization catalysis of lactide (LA) and ϵ‐caprolactone (ϵ‐CL) in this work. The polymerization is initiated in situ by the ring‐opening of epoxide compounds, in which the ionic cocatalyst could accelerate the reaction process. The Mn−Mn coordination effect contributes to the higher activity and iso‐selectivity towards LA compared to the mononuclear Salen‐Mn catalyst. The reactivity and stereoselectivity are determined by the conformation of catalysts, specifically the Mn−Mn separation and dihedral angle. Finally, the CO2‐controlled switchable polymerizations are carried out with LA and ϵ‐CL. The reversibility of the on‐off switching operation is influenced by the combination between CO2 molecules and active species. The success in binuclear Salen‐Mn catalysts not only expands the range of bimetallic catalyst analogues but also claims the promising potential of Mn‐based catalysts in practical and theoretical research.
Total Chemical Synthesis of the SARS‐CoV‐2 Spike Receptor‐Binding Domain
Authors: Kar Abhisek , Jana Mrinmoy , Malik Vishal , Sarkar Arighna , Mandal Kalyaneswar 
Published: October 2023

AbstractSARS‐CoV‐2 and its global spread have created an unprecedented public health crisis. The spike protein of SARS‐CoV‐2 has gained significant attention due to its crucial role in viral entry into host cells and its potential as both a prophylactic and a target for therapeutic interventions. Herein, we report the first successful total synthesis of the SARS‐CoV‐2 spike protein receptor binding domain (RBD), highlighting the key challenges and the strategies employed to overcome them. Appropriate utilization of advanced solid phase peptide synthesis and cutting‐edge native chemical ligation methods have facilitated the synthesis of this moderately large protein molecule. We discuss the problems encountered during the chemical synthesis and approaches taken to optimize the yield and the purity of the synthetic protein molecule. Furthermore, we demonstrate that the chemically synthesized homogeneous spike RBD efficiently binds to the known mini‐protein binder LCB1. The successful chemical synthesis of the spike RBD presented here can be utilized to gain valuable insights into SARS‐CoV‐2 spike RBD biology, advancing our understanding and aiding the development of intervention strategies to combat future coronavirus outbreaks. The modular synthetic approach described in this study can be effectively implemented in the synthesis of other mutated variants or enantiomer of the spike RBD for mirror‐image drug discovery.
Cobalt‐Catalyzed Bis‐Borylation of Quinolines: The Importance of the Cobalt Triplet State
Authors: Bories Cassandre Cassiopée , Gontard Geoffrey , Barbazanges Marion , Lemière Gilles , Petit Marc 
Published: October 2023

AbstractWe report herein a mild stereo‐ and regioselective dearomatization of quinolines using the simple low valent HCo(N2)(PPh3)3 complex that exhibits labile ligands. Conditions to form selectively, at room temperature, high‐valued 1,4‐bis‐borylated tetrahydroquinolines from simple starting heteroaromatic compounds have been developed. The efficient and selective functionalization of a large scope of quinolines bearing various electron‐donating or electron‐withdrawing substituents is presented, as well as the post‐modification of the resulting C−B bond. NMR and labelling studies are consistent with a cascade mechanism pathway, starting from an in situ generated paramagnetic bis‐quinoline cobalt(I) hydride complex. A first quinoline dearomatization followed by a cobalt(I)‐catalyzed Markovnikov hydroboration of the remaining double bond allows the introduction of the boronic ester group only at C4 position. DFT calculations particularly highlight the importance of the cobalt triplet state throughout the reaction pathway, and bring some rationalization for the observed C4 selective borylation.
Der Rote Keulenkopf
Authors: Petersen Frank 
Published: October 2023

ZusammenfassungAlle Ausgangsverbindungen für Ergot‐Medikamente, unter denen Lysergsäure die wichtigste ist, konnten anfangs nur über die Kultivierung der Sklerotien auf Roggenpflanzen gewonnen werden. 1960 und 1964 gelang italienischen Projektteams unter Leitung des deutsch‐britischen Chemikers Ernst Boris Chain und der Naturstoffforschung der Sandoz AG in Basel der Durchbruch in der fermentativen Produktion von Lysergsäureverbindungen in Bioreaktoren. In den USA klärte der deutsche Chemiker Heinz Floss die Biosynthese der Lysergsäure und weiterer Ergotalkaloide auf, indem er Pilzflüssigkulturen radioaktiv markierte Bausteine zusetzte. 1999 identifizierten die Arbeitsgruppen von Paul Tudzynski (Universität Münster) und Ullrich Keller (TU Berlin) im Genom des Roten Keulenkopfs das gesamte Gencluster der Ergotaminbiosynthese, das die enzymatischen Schritte zur Ergotaminbildung orchestriert. Die Ergotoxikose des Menschen tritt heute nur noch sporadisch in Entwicklungsländern auf, wo Maßnahmen zur Reduktion des Mutterkorns in der Ernte und eine engmaschige Überwachung des Toxingehalts im Getreide nicht durchgehend eingehalten werden können. Ihr gegenüber ist der gangränöse Ergotismus durch kontaminierte Futtergräser in der Weidetierhaltung noch immer ein weltweites Problem für die Landwirtschaft und Zuchtbetriebe. Die Rezeptoren, über die Ergotalkaloide eine gangränöse Toxikose hervorrufen können, sind heute verstanden. Die auffallende Ähnlichkeit der Symptome des konvulsiven Ergotismus und des medikamentösen „Serotonin‐Syndroms“, wie sie der australische Neurologe Mervyn J. Eadie aufzeigte, ist ein passabler Analogieschluss, welche Rezeptortypen an dieser Form einer Ergotoxikose beteiligt sein könnten. 2022 klärte der US‐amerikanische Pharmakologe Bryan Roth mit Hilfe der neuartigen Kryoelektronenmikroskopie die Bindung des LSD an die 5‐HT2A/2B‐ Rezeptoren auf. Anhand der hochaufgelösten neuen Strukturdaten konnte der chinesische Forscher Sheng Wang Moleküle designen, die im Mäusemodel antidepressiv wirkten, ohne halluzinogen zu sein. Gegenwärtig wird LSD in der klinischen Psychiatrie wieder erforscht, um seinen therapeutischen Nutzen bei schwer behandelbaren Depressionen, Traumafolgestörungen, Angstzuständen oder beim Clusterkopfschmerz zu bewerten.
Computational evaluation of heart failure and continuous flow left ventricular assist device support in anaemia
Authors: Bozkurt Selim 
Published: October 2023

AbstractAnaemia is common in end‐stage heart failure patients supported with continuous flow left ventricular assist device (CF‐LVAD) and is associated with adverse outcomes such as heart failure readmission. This study evaluates the haemodynamic effects of anaemia on cardiac function and cerebral blood flow in heart failure patients supported with CF‐LVAD using computational simulations. A dynamic model simulating cardiac function, systemic, pulmonary and cerebral circulations, cerebral flow autoregulatory mechanisms and gas contents in blood was used to evaluate the effects of anaemia and iron deficiency in heart failure and during CF‐LVAD support. CF‐LVAD therapy was simulated by a model describing HeartMate 3. Anaemia and iron deficiency were simulated by reducing the haemoglobin level from 15 to 9 g/dL and modifying scaling coefficients in the models simulating heart chamber volumes. Reduced haemoglobin levels decreased the arterial O2 content, which increased cerebral blood flow rate by more than 50% in heart failure and during CF‐LVAD assistance. Reduced haemoglobin levels simulating anaemia had minimal effect on the arterial and atrial blood pressures and ventricular volumes. In contrast, iron deficiency increased end‐diastolic left and right ventricular diameters in heart failure from 6.6 cm to 7 cm and 2.9 cm to 3.1 cm and during CF‐LVAD support from 6.1 to 6.4 cm and 3.1 to 3.3 cm. The developed numerical model simulates the effects of anaemia in failing heart and during CF‐LVAD therapy. It is in good agreement with clinical data and can be utilised to assess CF‐LVAD therapy.
Effect of Modified Biochar Prepared by Co‐pyrolysis of MgO on Phosphate Adsorption Performance and Seed Germination
Authors: Tu Panfeng , Zhang Guanlin , Cen Yingyuan , Huang Baoyuan , Li Juan , Li Yongquan , Deng Lifang , Yuan Haoran 
Published: October 2023

AbstractBiochar is currently used as a phosphate adsorbent in water and subsequently as a soil amendment. In this study, modified biochar was prepared directly by co‐pyrolysis of MgO and rice straw, and a preliminary ecotoxicological assessment was performed before the application of modified biochar to soil. The effects of single factors, such as pyrolysis temperature, dosage, pH, and coexisting ions, on phosphate adsorption performance were investigated. In addition, after phosphate adsorption, the effects of modified biochar leachate on the germination of corn and rice seeds were examined. The results showed that phosphate adsorption by the modified biochar first increased and then decreased as the pyrolysis temperature increased, with modified biochar prepared at 800 °C showing the greatest adsorption. In addition, a comprehensive cost analysis showed that the best phosphate adsorption effect of modified biochar was achieved at a dosage of 0.10 g and a solution pH of 3. In contrast, the presence of competitive coexisting ions, Cl−, NO3−, CO32−, and SO42−, reduced the phosphate adsorption capacity of the modified biochar. The adsorption kinetics results revealed that the process of phosphate adsorption by the modified biochar was more in line with the pseudo‐second‐order model and dominated by chemisorption. Moreover, the adsorption isotherm results indicated that the process was more in line with the Langmuir model and dominated by monomolecular layer adsorption, with a maximum adsorption of 217.54 mg/g. Subsequent seed germination tests showed that phosphate‐adsorbed modified biochar leachate had no significant effect on the germination rate of corn seeds, whereas it improved the germination rate of rice seeds. Together, these results provide guidance for the application of modified biochar firstly as an adsorbent of phosphate and subsequently as a soil remediator.
Cerebral hemiatrophy and hemiparesis following hemiclonic status epilepticus in Dravet syndrome
Authors: Caraballo Roberto , Guzman Ariel , Beltrán Lucas , Espeche Alberto 
Published: October 2023

AbstractDravet syndrome is currently considered as an developmental and epileptic encephalopathy and, recently, mandatory, alert, and exclusionary criteria have been proposed. Here, we describe three patients with Dravet syndrome with the typical early presentation including febrile and afebrile alternating hemiclonic seizures due to loss‐of‐function SCN1A variants. Subsequently, they developed episodes of febrile focal status epilepticus (SE) associated with hemiparesis and cerebral hemiatrophy with posterior focal seizures, as a consequence of Dravet syndrome. This sequence of events has been previously published in patients with Dravet syndrome and does not contradict the recent classification by the International League Against Epilepsy (ILAE). The ILAE guidance identifies “Focal neurological findings” as alert criteria and “MRI showing a causal focal lesion” as exclusionary criteria for making an initial diagnosis of Dravet syndrome at presentation. Our three patients would correspond to a severe phenotype, similar to the well‐known presentation of generalized atrophy following prolonged status epilepticus. Common genetic findings in cases of diffuse and unilateral brain involvement may help explain these clinical presentations. Further genotype–phenotype studies may provide additional insights into this electroclinical behavior.
Prevalence of epilepsy in Morocco: A population‐based study
Authors: Souirti Zouhayr , Hmidani Mohammed , Lamkadddem Abdelaziz , Khabbach Kawtar , Belakhdar Salma , Charkani Doae , Mhandez Tlemcani Driss , Lahmadi Nabila , El Akramine Maroua , Erriouiche Samira , Berrada Asmae , Ahniba Asmae , Omari Mohammed , El Fakir Samira , Tachfouti Nabil , Rafai Mohammed Abdoh , Chahid Imane , Meriam Bentahar , Jilla Mariam , Ghaname Aayad , Benmansour Youssef , Filali Zegzouti Younes , Kissani Najib , Lakhdar Abdelhakim , Belfkih Rachid , Aggouri Mohamed , Ouazzani Reda , Chahidi Abderrahmane , Janati Idrissi Abdelkrim 
Published: October 2023

AbstractObjectiveIn Morocco, there was a lack of data related to the epidemiology of epilepsy. This data serves as a useful basis for the development of any national intervention or action program against epilepsy in Morocco. Through this study, we aimed to estimate the active and lifetime prevalence of epilepsy in Morocco.MethodsWe collected data from eight out of 12 Moroccan regions in two steps: In the screening step, we first used a nationwide telephone diagnosis questionnaire and in the second stage, a team of physicians under the direction of an epileptologist conducted a confirmative survey for suspected cases. We fixed the confidence interval at α = 5% and the precision at 0.02.ResultsUp to 3184 responded positively to our invitation to participate in this study and were able to answer the questions of the first diagnostic questionnaire. In the diagnostic phase, physicians in neurology reinterviewed all 86 suspected cases using a confirmative diagnosis questionnaire, and 63 persons were confirmed as having lifetime epilepsy and 56 with active epilepsy. The mean age (Mean ± SD) of persons with epilepsy was 35.53 years (±21.36). The prevalence of lifetime and active epilepsy were 19.8 (19.6–20.0) and 17.6 (17.5–17.8) per 1000 (95% confidence interval), respectively.SignificanceThis is the first study to estimate the active and lifetime prevalence of epilepsy in Morocco according to the international recommendations of the ILAE. The prevalence of lifetime and active epilepsy were 19.8 (15–24.6) and 17.6 (13.3–22.8) per 1000, respectively. We included both children and elderly subjects. The rates of active and lifetime population epilepsy prevalence in Morocco ranged between Asian and sub‐Saharan Africa low‐ and middle‐income countries.
First description of buccopharyngeal anatomy in Pelodryadinae larvae: Morphological comparison and systematic implications (Anura: Hylidae: Pelodryadinae: Litoria rubella and Ranoidea caerulea)
Authors: Dias Pedro Henrique dos Santos 
Published: October 2023

AbstractPelodryadinae, the Australian tree frogs, is a monophyletic group endemic to the Australo‐Papuan region. Although we have a relatively good knowledge about tadpoles' phenotypic diversity in terms of external morphology, information about internal anatomy is rare for the subfamily; for instance, their buccopharyngeal cavity is completely unknown. Herein I describe for the first time the buccopharyngeal anatomy of two pelodryadins: Litoria rubella and Ranoidea caerulea. I compare my results with available evidence from Phyllomedusidae, that is, the sister clade to Pelodryadinae, and briefly comment on buccopharyngeal cavity within Hylidae. Both species can be readily distinguished based on lateral ridge, postnarial, buccal roof arena, infralabial papillae, and lingual papillae. Variation between the two species may suggest a large diversity within Pelodryadinae. Pelodryadinae and Phyllomedusinae present similar buccopharyngeal morphologies, although Agalychnis callidryas has a unique morphology and putative apomorphic transformations can be observed in Pithecopus + Phyllomedusa, Ranoidea, and Phasmahyla.