bluuebunny/crossref_metadata_2025 huggingface dataset:
Translational motion and hydration of the symmetrical tetraalkylammonium ions in aqueous solution
Authors: Hertz H. C. , Lindman B. , Siepe V.
Published: October 2023

The self‐diffusion coefficients of (CH3)4NCl, (C2H5)4NCl, (C3H7)4NCl, and (C4H9)NCl in aqueous solution together with the self‐diffusion coefficient of H2O in the same solutions have been measured. Comparison of the corresponding pair of diffusion coefficients showed that a rigid long‐lived hydration sphere of the cations does not exist – or that such an existence is at best very unlikely. Proton and deuteron nuclear magnetic relaxation rates of (CX3)4NCl and (C2X5)4NCl, X = H, D, in aqueous solution gave evidence for the existence of cation‐cation contact for the ion (C2H5)4N+.
Molecular motions in the hydration sphere of the F−ion in aqueous solution. (with some results for HF, HF2, and BF)
Authors: Hertz H. G. , Keller G. , Versmold H.
Published: October 2023

Experimental results for the F19nuclear magnetic relaxation rate in aqueous solutions of NaF, KF, RbF and CsF as a function of the concentration are reported. Using these data together with the proton relaxation behaviour in the same solutions three models for the hydration sphere are discussed: A long‐lived rigid and non‐rigid hydration sphere and a short‐lived hydration sphere. Then, experimental results for the self‐diffusion coefficient of the F−ion in aqueous solution together with the corresponding H2O self‐diffusion coefficients are reported. The analysis of all these data yields the result that the F−hydration sphere is non‐rigid and probably fairly short‐lived. ThepH dependence of the F−relaxation is evaluated to give the reorientational correlation times of HF and HFand from the F relaxation in NaBF4solution we derive the reorientational correlation time of the BFion.
Indirekte Kernspinkopplung in organischen Phosphor‐ und Siliziumverbindungen
Authors: Elser H. , Dreeskamp H.
Published: October 2023

Durch H‐{H}‐, H‐{C}‐, H‐{Si}‐, H‐{P}‐ und H‐{Sn}‐Doppelresonanzexperimente wurden die Größe und Vorzeichen der Kopplungskonstanten von Tetramethylphosphonium, Trimethylphosphin und Phosphinen der Form (C6H5)2PX(CH3)3 mit X = C, Si, Sn sowie von den zu den Phosphoniumionen isoelektronischen Si‐Verbindungen (C6H5)3SiX(CH3)3 bestimmt. Die normierten Kopplungskonstanten 1J′SiX der Silylverbindungen bzw. 1J′PX in Tetramethylphosphonium sind positiv und 1JPX ist negativ in den Phosphinen. Ihr Absolutbetrag steigt stark mit steigender Ordnungszahl von X. Sowohl 2JPXC wie auch 3JPXCH der Phosphine sind positiv und nehmen mit steigender Ordnungszahl von X ab. In P(CH3)3 und P(CH3) sind sowohl 3JCH als auch 4JHH positiv. Diese Daten lassen sich in die schon bekannten analogen Kopplungskonstanten der Methylverbindungen der IV. und VI. Hauptgruppen einordnen, und ihre Bedeutung für die Interpretation der indirekten Kernspinkopplung werden diskutiert.
Study of the Interrelation Between Reflection Coefficient and Solute Rejection Efficiency Using a Strong Basic Anion Exchange Membrane
Authors: Pusch W. , Woermann D.
Published: October 2023

The mechanical permeability and the reflection coefficient at 1 atm and 20°C as well as the solute rejection efficiency at 50 and 100 atm are determined for aqueous solutions of HCl, NaCl, MgCl2, and AlCl3 over a wide concentration range using a strong anion exchange membrane. Systems with positive reflection coefficients yield a positive solute rejection. Therefore, the solute concentration of the filtrate is smaller than that of the phase under hydrostatic pressure. Just the reverse is true for systems with negative reflection coefficients. These observations are in complete agreement with theoretical predictions based on thermodynamics of irreversible processes as well as on the quantitative treatment of the model of membranes with narrow pores. – Experimentally found differences in the concentration dependence of the reflection coefficients between a 2–1‐valent (MgCl2) and a 3 – 1 valent (AlCl3) electrolyte are predicted by the model of membranes with narrow pores.
A Laser Temperature‐Jump Apparatus and Fast Conductometric Detection for Relaxation Measurements
Authors: Koffer H.
Published: October 2023

A laser temperature‐jump apparatus with conductometric detection is described with which relaxations of few microseconds can be measured. Oscillations after the fast heating can be avoided by a special construction of the cell. Errors in the relaxation time due to the high measuring frequency are discussed quantitatively and a correction method is given.
Polarographische Untersuchungen zur Konformation von 1.2.3.4.5‐Pentaarylimidazoliumkationen
Authors: Heinze Jürgen , Baumgärtel Helmut
Published: October 2023

Basierend auf quantenmechanischen und geometrischen Modellbetrachtungen wird ein Verfahren angegeben, mit dem aus Halbstufenpotentialen reversibler polarographischer Stufen geeignet substituierter Verbindungen eine Aussage zur sterischen Konformation von “ overcrowded molecules” in Lösung gemacht werden kann.

Es wurden die Reduktionshalbstufenpotentiale von 1.2.3.4.5‐Pentaarylimidazoliumkationen bestimmt. Für die mittleren Torsionswinkel der Arylsubstituenten gegen die Ebene des Heterocyclus wurde ein Wert von 81° berechnet.
Induzierte optische Aktivität. Beitrag einer Charge‐Transfer‐Bande zur optischen Aktivitat von Elektronen‐Donator‐Akzeptor‐Komplexen
Authors: Briegleb G. , Kuball H.‐G. , Henschel K. , Euing W.
Published: October 2023

Bei Elektronen‐Donator‐Akzeptor‐Komplexen mit einer optisch aktiven Komponente zeigt sich im Bereich der Charge‐Transfer‐Bande ein Cotton‐Effekt (Circulardichroismus und Rotationsdispersion). Es wird gezeigt, β die induzierte optische Aktivität dem Charge‐Transfer‐Übergang zuzuordnen ist. Die beim Komplex Dikampfer‐Tetracyanäthylen gefundene Cotton‐Kurve wird analysiert.
Energy Transfer between Transition‐Metal Complexes in Aqueous Solution
Authors: Fujita Ichiro , Kobayashi Hiroshi
Published: October 2023

Electronic excitation energy transfer between tris(2,2′‐bipyridine)ruthenium(II), [Ru(bipy)3]2+, and chromate(III) complexes such as tri‐oxalatochromate(III), [Cr(ox)3]3‐, trimalonatochromate(III), [Cr(mal)3]3‐, and hexacyanochromate(III), [Cr(CN)6]3‐, was observed in aqueous solution. Kinetics of the energy transfer was studied for a variety of viscosity and ionic strength of the solution. The rate‐determining process of the energy transfer is an intermolecular process between counter complex ions in an ion pair forming in solution but not a diffusion‐controlled encounter process.

Main intermolecular path is an energy transfer from the charge‐transfer excited state in the ruthenium counterpart to the chromate(III) ligand‐field excited state in an ion pair. In a rigid solution, in fact, a sensitized phosphorescence of the chromate(III) complex was observed besides the phosphorescence of [Ru(bipy)3]2+ upon excitation of [Ru(bipy)3]2+ in the presence of the chromate(III) complex. Since the excited [Ru(bipy)3]2+ is deactivated before an effective encounter to the chromate(III) complex in such a highly viscous media, the sensitized phosphorescence could not be expected for a diffusion‐controlled process.

From a static Stern‐Volmer relationship, the ionic association constants of [Ru(bipy)3]2+ with [Cr(ox)3]3‐ [Cr(mal)3]3‐ and [Cr(CN)6]3‐ at 25°C were obtained being extrapolated to zero ionic strength as 7.82 × 1031.mol−1, 3.26 × 1031.mol−1 and 9.48 × 1031.mol−1.
Reaktion von O(3P)‐atomen mit Allen
Authors: Herbrechtsmeier P. , Wagner H. G.
Published: October 2023

In einem isothermen Strömungssystem wurde die Reaktion von (3P)O‐Atomen mit Allen bei 5 Torr und Temperaturen von 275 bis 375 K im Trägergas Helium untersucht. Als Hauptprodukte treten C2H4 und CO auf, die sehr wahrscheinlich direkt gebildet werden. Für die Geschwindigkeitskonstante der Reaktion O + C3H4 → C2H4 + CO ergab sich
Reaction rate constants of first and second kind for solid state reactions
Authors: Pelton A. D. , Schmalzried H. , Greskovich C. D.
Published: October 2023

A generalized theory of reaction rate constants for solid‐solid and gas‐solid reactions is presented by which rate constants may be related to the elementary parameters of the system. Relationships between rate constants for reactions of the “first kind” when there is mutual solubility and transport in the reactant phases, and for reactions of the “second kind” between presaturated reactants are formulated. The dependence of the interdiffusion coefficients in the reactants on composition, as well as the corrections for the fact that the phase boundaries are moving, enter the equations only through one simple function fi, thereby making the formulas simple and completely general. Two practically important limiting cases are considered in detail, where the interdiffusion coefficient is independent and linearly dependent on composition in the reactants. Numerical examples are given for NiCr2O4 and MgCr2O4 spinel formation. There is a 17 to 25% decrease in the growth rate of NiCr2O4 between 1330° and 1580°C because of the diffusion of Cr3+ into NiO.
Zum Ladungsdurchtritt durch Kupfer(I)oxid‐Kathoden
Authors: Hauffe K. , Reinhold K.
Published: October 2023

Das kathodische Verhalten von Cu2O‐Einkristallen wurde in einer elektrochemischen Zelle untersucht, die sowohl organische als auch wäßrige Elektrolyte enthielt. Nach geeigneter Vorbehandlung der Kristalle wurde im Dunkeln, entsprechend der durch kathodische Polarisation im Cu2O nahe der Phasengrenze Cu2O/Elektrolyt verursachten Verarmung an Defektelektronen, gewöhnlich ein sehr geringer Stromfluß beobachtet. Nur wenn der Elektrolyt ein System enthielt, wie z. B. J−3‐Ionen, das geeignet war, Defektelektronen ins Valenzband zu injizieren, konnte der kathodische Dunkelstrom erheblich vergrößert werden.

Wir nehmen daher an, daß eine zu große Energiedifferenz Ec ‐ EF (Redox) zwischen der Unterkante des Leitungsbandes Ec und dem Fermipotential EF (Redox) des Redoxsystems für dieses Verhalten verantwortlich ist. Für die durch Licht im Leitungsband des Cu2O erzeugten Elektronen konnte kein Redox‐System weder in organischen noch in wäßrigen Elektrolyten gefunden werden, das mit diesen merklich reagierte.
Voltammetrische Untersuchungen an elektrokatalytisch wirksamen Phthalocyaninen und Tetraazaannulenen in konzentrierter Schwefelsäure
Authors: Beck Fritz
Published: October 2023

Unter den Metallchelaten des Phthalocyanins (Me‐Pc), des polymeren Phthalocyanins und des Tetraazaannulens (Me‐TAA) mit Me = H, Fe, Co, Ni und Cu befinden sich Vertreter hoher Aktivitä bezüglich einer Elektrokatalyse der Sauerstoffreduktion. Aus voltammetrischen Messungen an den in 85‐96% Schwefelsäure gelösten Chelaten wurden Oxidations‐ und Reduktionspotentiale erhalten, die teils einer Umladung des Zentralatoms (Einelektronenstufen), teils der Reduktion oder Oxidation des Ringsystems in Ein‐ bis Achtelektronenstufen zuzuordnen sind. Die besonders aktiven Elektrokatalysatoren (Fe‐Pc, Co‐TAA) sind gekennzeichnet durch eine positive Potentiallage der Redoxpotentiale und durch eine ausgeprägte Positivierung der polarographischen Sauerstoffstufe in 85% iger Schwefelsäure. Dies führt zu einem Mechanismus der Sauerstoffreduktion, die als “Redoxkatalyse” bezeichnet wird. In einer chemischen Teilreaktion oxydiert der am Chelat koordinierte Sauerstoff den Katalysator zum Kation. Hierauf folgt die elektrochemische Reduktion des Kations zu der Ausgangsverbindung. Die Konsequenzen dieses Modells bezüglich Aktivität und Stabilität der Elektrokatalysatoren werden diskutiert.
Kalorimetrische Untersuchungen an Silberbromid‐Kupfer(I)bromid‐Mischkristallen
Authors: Bremer F. , Nölting J.
Published: October 2023

Die spezifischen Wärmen von AgBr ‐ CuBr‐Mischkristallen mit Anteilen an AgBr zwischen 40 und 90 Molprozent wurden von 50°C bis zu den Soliduspunkten bestimmt.

Neben der weiteren Aufklärung des Zustandsdiagramms durch genaue Bestimmung einzelner Phasengrenzpunkte ergeben sich aus dem Temperaturverlauf von cp im Bereich der δ‐AgBr‐Phase Aussagen über die Art der Fehlordnung. Hiernach liegt bereits für CuBr‐Anteile oberhalb 25 Molprozent strukturelle Fehlordnung des Kationengitters vor. Dieser Befund steht im Einklang mit der seit langem bekannten extrem hohen Zunahme der Ionenleitfähigkeit bei ansteigendem CuBr‐Gehalt.

Ein aus früheren Messungen von Teltow vermutetes Minimum der Phasengrenzlinie zwischen δ‐ und α‐Phase im Bereich von 45 Molprozent AgBr konnte bestätigt werden. Die Umwandlung δ → α findet hier bei völlig fehlgeordnetem Kationengitter statt.
Protonation of Aromatic Molecules on the Surface of Cracking Catalysts
Authors: Hecht Harry G. , Kortüm G.
Published: October 2023

A series of methyl‐substituted benzene compounds and condensed nuclear hydrocarbon compounds have been studied on activated cracking catalyst surfaces using reflectance spectroscopic techniques. It was found that very intensely colored samples were obtained by activation with Brönsted acids. This coloration is attributed primarily to the formation of protonated aromatic molecule ions on the surface. The nature of these ions is discussed, and evidence is presented to support the hypothesis that protonation is involved. Some implications of these observations with regard to the mechanism of catalysis are also mentioned.
Synthesis and Spectra of Rhodium (III) Complex Compounds VI. Luminescence Spectra and Some Model Interpretations
Authors: Hoggard Patrick E. , Schmidtke Hans‐Herbert
Published: October 2023

The luminescence spectra of a number of rhodium(III) complexes have been measured and interpreted in terms of a 3T1g → 1A1g (in octahedral notation) transition. Variations in band widths and Stokes shifts have been incorporated into a semi‐empirical model for optical transitions of transition metal complexes in condensed systems. Using one of the model parameters a spectrochemical series based on absorption and emission spectra together may be set up. Other model parameters lead to conclusions as to the relative extent of π‐electron donation.
Die PVT‐Daten des geschmolzenen Wismutchlorids bis 1200 °C und 3,5 kbar
Authors: Treiber G. , Tödheide K.
Published: October 2023

Die PVT‐Daten des geschmolzenen Wismutchlorids wurden in einem innengeheizten Hochdruckgefäß bis 1200°C und 3,5 kbar gemessen. Die Dichte ändert sich im ausgemessenen Bereich um mehr als einen Faktor zwanzig. Das Wismutchlorid unterscheidet sich in seinem PVT‐Verhalten kaum von molekularen Flüssigkeiten, obwohl es bei hohen Dichten vorwiegend aus Ionen besteht. Die Zustandsgleichung von Redlich und Kwong vermag mit einem über ein Optimierungsverfahren angepaßten Satz von Konstanten die experimentellen Dichtewerte mit einer dem Meßfehler vergleichbaren Ungenauigkeit wiederzugeben.
Untersuchung der Rekombination von Jodatomen in stark komprimierten Gasen und in Flüssigkeiten
Authors: Hippler H. , Luther K. , Troe J.
Published: October 2023

Es wurde die Rekombination von Jodatomen mit Hilfe der Laser‐Blitzlichtphotolyse und der konventionellen Blitzlichtphotolyse in hoch verdichteten Gasen und in Flüssigkeiten untersucht. Die Drücke der verwendeten Trägergase M = He, Ne, Ar, Kr, Xe, H2, N2, O2. CO2, CH4, C2H6 und C3H8 wurden in groβen Bereichen, z. T. zwischen 0,5‐1000 atm variiert; auch wurden Messungen in flüssigen Xe, CO2, C2H6 und C3H8 ausgeführt. In allen untersuchten Fällen wurden mit steigender Dichte der Trägergase Wechsel der Reaktionsordnung beobachtet: für He von 3 über etwa 2,5 wieder nach 3, für Ne, Ar, Kr, Xe, H2, N2, O2, CO2, CH4 und C2H6 in verschiedener Weise von 3 nach etwa 2, für C3H8 von 3 nach etwa 3,3. Die Geschwindigkeitskonstanten in der Flüssigkeit schlieβen glatt an diejenigen in der Gas‐phase an. Anhand der Durckabhängigkeit der Geschwindigkeitskonstanten wird die Bedeutung des Energieübertragungs‐ und des Komplex‐mechanismus diskutiert. Es werden die Gleichgewichtskonstanten der Komplexe J + M ⇌ JM abgeschätzt.
Electron Paramagnetic Relaxation and EPR‐Line Shapes of Manganese Ions in a Sulfonated Polystyrene Ion‐Exchange Resin at Various Degrees of Hydration
Authors: Von Goldammer E. , Müller A. , Conway B. E.
Published: October 2023

Line shapes of electron paramagnetic resonance spectra of Mn2+‐ions in a sulfonated polystyrene ion‐exchange resin at varying degrees of hydration and temperatures have been examined at two microwave frequencies, 9 and 35 GHz. From a comparison between measured and simulated EPR‐spectra, the correlation times for the process modulating the zerofield splitting (zfs) interaction and the magnitude of the zfs‐parameters have been determined. For all samples with a water concentration higher than three molecules per sulfonate group, the correlation times were in the range of 10–40 ps, indicating a relatively high mobility of the hydrated cations in the polymer matrix. At lower water concentrations, forbidden transitions (Δm = ±1) have been observed. Their intensities increase with falling water concentrations and temperatures. Their temperature dependence was used to determine the fraction of metal ions associated at low water concentrations with the anchored sulfonate groups for a mean life‐time, τass≥10ns.
Interpretation of the Vapour Pressure Isotope Effect of BCl3
Authors: Jancsó G.
Published: October 2023

The available experimental data on the vapour pressure isotope effect (VPIE) of BCl3 are interpreted in the light of the theory of isotope effects in condensed systems. It is shown that the temperature dependence of the VPIE of 10BCl3/11BCl3 observed by Rayleigh distillation is of the wrong sign. The measured normal VPIE for B35Cl3/B37Cl3 is in satisfactory agreement with that obtained by the model calculation.
Formation and Reactions of Long Lived Xanthene Dye Radicals. III. Spectroelectrochemical Investigations on the Reduction of Xanthene Dyes
Authors: Krüger U. , Memming R.
Published: October 2023

In connection with photochemical studies on the formation of certain xanthene dye radicals spectroelectrochemical investigations have been performed in order to obtain data on the stability of semireduced xanthene dye radicals which were required for the interpretation of the photochemical measurements described in parts I and II of this series of papers.
Neuere Untersuchungen zum thermischen Zerfall von CO2. Teil II
Authors: Wagner H. Gg. , Zabel F.
Published: October 2023

Die Dissoziationsgeschwindigkeit von CO2 wurde in starker Verdünnung mit Ar in Stoßwellen bei hohen Gesamtdichten (10−4 mol/cm3 ≤ [M] ≤ 10−3 mol/cm3) gemessen. Die Extrapolation der Meßergebnisse zu hohen Drücken führte zu dem Arrhenius‐Ausdruck

equation image

für die Geschwindigkeitskonstante des thermischen Zerfalls im Hochdruckbereich. Die bisherigen Ergebnisse über die Geschwindigkeit der Reaktionen

equation image

werden einheitlich mittels der Beziehung kd/kr = K in Form der Rekombinationskonstanten dargestellt. Die Ergebnisse über die Druckabhängigkeit von k1a bei Zimmertemperatur und über die Temperaturabhängigkeit von k1a sowohl im Niederdruckbereich als auch im Hochdruckbereich werden diskutiert. Die Temperaturabhängigkeit der Rekombinationskonstanten kr,0 im Niederdruckbereich läßt sich in einem weiten Temperaturbereich durch den Ausdruck

equation image

beschreiben, kr,0 durchläuft zwischen 800 und 1600 K ein Maximum. Die Messungen im Hochdruckbereich lassen sich durch einen Arrhenius‐Ausdruck für kr,∞ mit einer formalen Aktivierungsenergie von etwa 3,5 kcal/mol im gleichen Temperaturbereich beschreiben. Einige einfache Reaktionsmechanismen werden im Hinblick auf die experimentellen Ergebnisse diskutiert.
Messungen des spezifischen Volumens von flüssigem Wasser zwischen 100°C und 300°C bis zu Drücken von 750 bar
Authors: Garnjost H.
Published: October 2023

Im Temperaturbereich zwischen 100°C und 300°C wurden im Druckwassergebiet neue p.v, T‐Messungen ausgeführt. Diese Messungen erscheinen erforderlich, da die älteren Meßwerte aus der Literatur gerade in diesem Temperaturintervall recht unzuverlässig sind, während im tieferen Temperaturbereich recht genaues Datenmaterial vorliegt. Die neu gemessenen p, v, T‐Tripel an Wasser werden mit der Fundamentalgleichung von Pollak verglichen.
Deuterium‐NMR‐Untersuchungen an Phospholipiddoppelschichten
Authors: Seelig Anna , Seelig Joachim
Published: October 2023

Phospholipiddoppelschichten sind die Grundbausteine vieler biologischer Membranen. Die Anordnung und die Konformation der Lipid‐ketten in der Doppelschicht konnte bisher nur mit Nitroxid‐Spin‐Labeln untersucht werden. Eine gleichwertige Methode ist Deuterium‐Magnetische Resonanz von spezifisch deuterierten Phospholipiden. Die anisotrope Bewegung der Lipidketten führt zu einer Aufspaltung des Deuterium‐Signals in ein Dublett, wobei der Linienabstand in einfacher Weise mit dem Ordnungsgrad des deuterierten Kettensegments verknüpft ist. Verglichen mit der Nitroxid‐Spin‐Label‐Methode hat die Deuterium‐Methode den Vorteil, daß sie keine Störung in der Lipiddoppelschicht verursacht. Messungen mit spezifisch deuterierten L‐α‐Dipalmitoyllecithinen führen zu einem kooperativen Modell für die Bewegung der Lipidketten.
Interdiffusion in (A,B)O‐type Solid Solutions and the Validity of Darken′s Equation
Authors: Yurek G. J. , Schmalzried H.
Published: October 2023

Relations between tracer diffusion coefficients and interdiffusion coefficients for quasibinary oxide solid solutions are derived. It is demonstrated that under certain conditions Darken‐type equations are obtained. By inserting experimentally determined interdiffusion coefficients and tracer diffusion coefficients in the Darken relation for (Co,Mg)O and (Co,Ni)O at 1300°C in air it is shown that the Darken‐type equation cannot be employed for interdiffusion in these systems. This is attributed to deviations from local point defect equilibrium in the diffusion couple, which is contrary to a major assumption in the derivation. Experimentally determined interdiffusion coefficients and tracer diffusion coefficients for Co‐cations are reported for various compositions in (Co,Mg)O at 1300°C in air.
Investigating the association between vitamin D dietary intake during pregnancy and incidence of clubfoot in neonates
Authors: Idriss Haitham T. , Werler Martha M.
Published: October 2023

Aims

Talipes equinovarus (clubfoot) is a congenital lower foot deformity that results from a neuromuscular deficiency, but the precise etiology remains elusive. Vitamin D is important for fetal neuromuscular development. In this study, we investigated the association between dietary vitamin D intake during pregnancy and incidence of clubfoot in neonates, since such a question has thus far been overlooked.

Methods

We conducted a secondary analysis of data collected in the United States, between 2007 and 2011 for a case–control study of children born with clubfoot. Participating mothers were interviewed by telephone about dietary and other health and life‐style indicators. Exposure to vitamin D was recorded as the average daily intake of dietary vitamin D over a period of 6 months before pregnancy began. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression.

Results

The dataset included 2667 study participants, of which 663 were cases. Logistic regression showed no significant association between dietary vitamin D or log10(Vitamin D) intake during pregnancy and incidence of clubfoot in neonates (OR = 1.00, CI = 1.00–1.00, OR = 1.51, CI = 0.83–2.82, respectively). No interaction in the regression model was found between vitamin D and other predictor variables. Results were not confounded by supplement intake of vitamin D during pregnancy.

Conclusions

Results show no evidence of an association between dietary vitamin D intake and incidence of clubfoot in neonates. The lack of association is not confounded by consumption of vitamin D supplements during pregnancy.
Detection of Minute virus of mice strains in different cell lines: Implications for adventitious agent testing
Authors: Farcet Maria R. , Modrof Jens , Antoine Gerhard , Klausen Cecilie , Kerschbaum Astrid , Kopp Martina , Dehghani Houman , Kreil Thomas R.
Published: October 2023

Minute virus of mice (MMV) has contaminated biotechnological processes in the past and specific MMV testing is therefore recommended, if the production cell line is known to be permissive for this virus. Testing is widely done using cell‐culture‐based adventitious virus assays, yet MMV strains may differ in their in vitro cell tropism. Here, we investigated the growth characteristics of different MMV strains on A9 and 324K cells and identified significant differences in susceptibility of these widely used indicator cell lines to infection by different strains of MMV, which has implications for MMV detectability during routine testing of biotechnology process harvests. An MMV‐specific polymerase chain reaction was evaluated as a more encompassing method and was shown as suitable replacement for cell culture‐based detection of the different MMV strains, with the additional benefit that detection is more rapid and can be extended to other rodent parvoviruses that might contaminate biotechnological processes. Although no MMV contamination event of human‐derived cell lines has happened in the past, biotechnological processes that are based on these also need to consider MMV‐specific testing, as, for example, HEK293, a human‐derived cell line commonly used in biopharmaceutical manufacturing, was shown as susceptible to productive MMV infection in the current work.
Orthotopic equine study confirms the pivotal importance of structural reinforcement over the pre‐culture of cartilage implants
Authors: de Ruijter Mylène , Diloksumpan Paweena , Dokter Inge , Brommer Harold , Smit Ineke H. , Levato Riccardo , van Weeren P. René , Castilho Miguel , Malda Jos
Published: October 2023

In articular cartilage (AC), the collagen arcades provide the tissue with its extraordinary mechanical properties. As these structures cannot be restored once damaged, functional restoration of AC defects remains a major challenge. We report that the use of a converged bioprinted, osteochondral implant, based on a gelatin methacryloyl cartilage phase, reinforced with precisely patterned melt electrowritten polycaprolactone micrometer‐scale fibers in a zonal fashion, inspired by native collagen architecture, can provide long‐term mechanically stable neo‐tissue in an orthotopic large animal model. The design of this novel implant was achieved via state‐of‐the‐art converging of extrusion‐based ceramic printing, melt electrowriting, and extrusion‐based bioprinting. Interestingly, the cell‐free implants, used as a control in this study, showed abundant cell ingrowth and similar favorable results as the cell‐containing implants. Our findings underscore the hypothesis that mechanical stability is more determining for the successful survival of the implant than the presence of cells and pre‐cultured extracellular matrix. This observation is of great translational importance and highlights the aptness of advanced 3D (bio)fabrication technologies for functional tissue restoration in the harsh articular joint mechanical environment.
Geographic variability and operator trends of transcatheter edge‐to‐edge repair in the United States
Authors: Heaton Joseph , Imburgio Steven , Dandu Sowmya , Johal Anmol , Udongwo Ndausung , Mararenko Anton , Asif Arif , Almendral Jesus , Sealove Brett , Selan Jeffrey , Kiss Daniel , Saybolt Matthew
Published: October 2023

Backgrounds

Transcatheter edge‐to‐edge repair (TEER) devices are used for primary mitral regurgitation (MR) and secondary MR. Despite the growing use of TEER devices, there have not been many studies on operator experience or procedure volumes by state.

Aims

We aimed to investigate nationwide operator volume trends and geographic variation in access to TEER.

Methods

The United States Center for Medicare and Medicaid Services (CMS) National Medicare Provider Utilization and Payment Database (MPUPD) was analyzed between 2015 and 2020 for initial TEER procedures.

Results

Procedure volume and total operators increased yearly from 2015 to 2019 but declined in 2020. Mean annual procedure volume per operator varied significantly by state, between 0 in multiple states and 35 in North Dakota. In 2019, 994 unique operators were identified, with 295 operators documented performing 10 or more procedures (29.68%). Operators performing 10 or more TEER procedures provided 68.46% of all operations in 2019, averaging 20.94 procedures per operator.

Conclusions

TEER procedures are becoming increasingly common as more operators are being trained. However, significant variability exists in the procedural volume per operator.
Right atrial thrombus removal with use of the ŌNŌ retrieval device
Authors: Herron Christopher , Batlivala Sarosh P. , Shahanavaz Shabana
Published: October 2023

Intracardiac masses and specifically right atrial thrombi can be difficult to manage and carry a high mortality rate. Typically, surgical removal or mechanical thrombectomy can be performed though may not be suitable for all patients. We present a unique case of a sickle cell patient with a large pedunculated right atrial thrombus that was successfully extracted using the novel ŌNŌ Retrieval Device.
The air flow resistance of glass fibre filter paper
Authors: Wheat J. A.
Published: October 2023

The air flow resistance of filter papers containing fine glass fibres was measured in the region of streamline flow. Average fibre diameters ranged from 0.18 to 14.4 microns and paper porosities from 0.75 to about 0.94. At atmospheric pressure, the data were correlated by the equation \documentclass{article}\pagestyle{empty}\begin{document}$ \Delta P = k\frac{{L\mu V}}{{g_c D_f^2 }}\frac{{\left({1 - \varepsilon } \right)}}{\varepsilon } $\end{document}

which was derived from an expression for the drag force on an individual fibre perpendicular to the direction of flow. The resistance coefficient k varied with fibre diameter according to the empirical relationship

and was about 30 for the largest fibre diameter and 1.6 for the smallest.

Two alternative methods are proposed for adapting the equation to pressures below atmospheric.
The decomposition of spent PETN nitration acids
Authors: Rodger I. , Mcirvine J. D.
Published: October 2023

The decomposition of PETN in pure nitric acid and of spent acids from nitrating pentaerythritol (PE) was followed by a continuous differential temperature measurement against a blank. Decomposition was more rapid as the temperature was raised and attained a maximum rate between 65–75% HNO3. Spent nitrating acids decomposed more rapidly than pure acids with PETN, due to the presence of about 0.5% dipentaerythrital hexanitrate (DiPEHN) formed from dipentaerythritol in the original PE. The decomposition of PETN in nitric acids was strongly catalysed by NO2, especially at high acid strength. The course of the decomposition as deduced from this evidence appeared to embrace (1) hydrolysis, (2) oxidation of hydrolysis products liberating NO2, (3) destruction of PETN by a mechanism catalysed by NO2in which hydrolysis plays no part.
Prediction of the potentially suitable areas of Leonurus japonicus in China based on future climate change using the optimized MaxEnt model
Authors: Wang Yongji , Xie Liyuan , Zhou Xueyong , Chen Renfei , Zhao Guanghua , Zhang Fenguo
Published: October 2023

Leonurus japonicus Houtt. is a traditional Chinese medicinal plant with high medicinal and edible value. Wild L. japonicus resources have reduced dramatically in recent years. This study predicted the response of distribution range of L. japonicus to climate change in China, which provided scientific basis for the conservation and utilization. In this study, 489 occurrence points of L. japonicus were selected based on GIS technology and spThin package. The default parameters of MaxEnt model were adjusted by using ENMeva1 package of R environment, and the optimized MaxEnt model was used to analyze the distribution of L. japonicus. When the feature combination in the model parameters is hing and the regularization multiplier is 1.5, the MaxEnt model has a higher degree of optimization. With the AUC of 0.830, our model showed a good predictive performance. The results showed that L. japonicus were widely distributed in the current period. The maximum temperature of warmest month, the min temperature of coldest month, the precipitation of wettest month, the precipitation of driest month, and altitude were the main environmental factors affecting the distribution of L. japonicus. Under the three climate change scenarios, the suitable distribution area of L. japonicus will range shift to high latitudes, indicating that the distribution of L. japonicus has a strong response to climate change. The regional change rate is the lowest under the SSP126‐2090s scenario and the highest under the SSP585‐2090s scenario.
Lignite‐Based Hierarchical Porous C/SiOx Composites as High‐Performance Anode for Potassium‐Ion Batteries
Authors: Yang Zexu , Zhao Shouwang , Jiao Rongji , Hao Gengyu , Liu Yunying , He Wenxiu , Chen Jingwei , Jia Guixiao , Cui Jinlong , Li Shaohui
Published: October 2023

Silicon oxide (SiOx, 0 < x ≤ 2) has been recognized as a prominent anode material in lithium‐ion batteries and sodium‐ion batteries due to its high theoretical capacity, suitable electrochemical potential, and earth abundance. However, it is intrinsically poor electronic conductivity and excessive volume expansion during potassiation/depotassiation process hinder its application in potassium‐ion batteries. Herein, we reported a hierarchical porous C/SiOx potassium‐ion batteries anode using lignite as raw material via a one‐step carbonization and activation method. The amorphous C skeleton around SiOx particles can effectively buffer the volume expansion, and improve the ionic/electronic conductivity and structural integrity, achieving outstanding rate capability and cyclability. As expected, the obtained C/SiOx composite delivers a superb specific capacity of 370 mAh g−1 at 0.1 A g−1 after 100 cycles as well as a highly reversible capacity of 208 mAh g−1 after 1200 cycles at 1.0 A g−1. Moreover, the potassium ion storage mechanism of C/SiOx electrodes was investigated by ex‐situ X‐ray diffraction and transmission electron microscopy, revealing the formation of reversible products of K6.8Si45.3 and K4SiO4, accompanied by generation of irreversible K2O after the first cycle. This work sheds light on designing low‐cost Si‐based anode materials for high‐performance potassium‐ion batteries and beyond.
STAT6‐induced production of mucus and resistin‐like molecules in lung Club cells does not protect against helminth or influenza A virus infection
Authors: Ruhl Andreas , Antão Ana Vieira , Dietschmann Axel , Radtke Daniel , Tenbusch Matthias , Voehringer David
Published: October 2023

Airway epithelial cells contribute to a variety of lung diseases including allergic asthma, where IL‐4 and IL‐13 promote activation of the transcription factor STAT6. This leads to goblet cell hyperplasia and the secretion of effector molecules by epithelial cells. However, the specific effect of activated STAT6 in lung epithelial cells is only partially understood. Here, we created a mouse strain to selectively investigate the role of constitutively active STAT6 in Club cells, a subpopulation of airway epithelial cells. CCSP‐Cre_STAT6vt mice and bronchiolar organoids derived from these show an enhanced expression of the chitinase‐like protein Chil4 (Ym2) and resistin‐like molecules (Relm‐α, ‐β, ‐γ). In addition, goblet cells of these mice spontaneously secrete mucus into the bronchi. However, the activated epithelium resulted neither in impaired lung function nor conferred a protective effect against the migrating helminth Nippostrongylus brasiliensis. Moreover, CCSP‐Cre_STAT6vt mice showed similar allergic airway inflammation induced by live conidia of the fungus Aspergillus fumigatus and similar recovery after influenza A virus infection compared to control mice. Together these results highlight that STAT6 signaling in Club cells induces the secretion of Relm proteins and mucus without impairing lung function, but this is not sufficient to confer protection against helminth or viral infections.
Assessing the effects of agricultural waste returning on soil moisture characteristics
Authors: Yu Haiying , Zhao Wenju , Ma Feng , Zeng Kai , Ma Fangfang
Published: October 2023

Agricultural waste is an emerging and promising resource due to its abundant organic compounds and high water‐holding capacity. It plays a crucial role in improving soil water use efficiency and contributing to sustainable agricultural development. This study aimed to investigate the impact of returning agricultural waste on soil moisture characteristics. Different volume ratios (4:5:1:0, 3:5:1:1, 2:5:1:2, 1:5:1:3, and 0:5:1:4) of agricultural waste blend (AWB) consisting of cattle manure, yellow loam soil, wheat straw, and distiller's grains were examined, and the water‐holding performance of the five AWB ratios under various suction forces was compared. The analysis confirmed the suitability of the Van Genuchten‐Mualem model for fitting soil moisture characteristic curves at different ratios. The study also examined the influences of AWB ratios on soil‐specific water capacity, hydraulic parameters, and equivalent pore size. The results showed that agricultural waste effectively increased soil‐specific water capacity, available water content, soil WHC(Water‐holding capacity), and soil pore count. Furthermore, reducing cattle manure and increasing distiller's grains enhanced these effects. For instance, when the AWB ratio was 0:5:1:4, soil‐specific water capacity increased by 47.7%, while field WHC and available water content increased by 9.9% and 3.8%, respectively. Additionally, the number of extremely small and small pores increased by 1.4% and 0.77%, respectively. These findings provide valuable theoretical guidance for agricultural waste treatment and improving soil WHC. Based on the results, it is recommended to increase the proportion of distiller's grains and reduce organic fertilizer when using agricultural waste for improving soil WHC.
Sinonasal NUT carcinoma: A consecutive case series and systematic review
Authors: Ramesh Uma , Contrera Kevin J. , Shakibai Nasim , Su Shirley Y. , Brahimaj Bledi , Roberts Dianna , Williams Michelle D. , Ferrarotto Renata , Phan Jack , Gunn Gary Brandon , Raza Shaan , DeMonte Franco , Hanna Ehab Y.
Published: October 2023

Background

Sinonasal NUT carcinoma is an extremely rare, lethal malignancy with limited literature.

Methods

A case series was conduction of all patients with sinonasal NUT carcinoma at a single institution between 2010 and 2022. Survival and associated were evaluated. A systematic review of the literature was performed.

Results

In 12 patients, followed for a median of 1.5 years, the median overall survival (OS) and disease‐specific survival (DSS) were both 14.6 months. Patients with maxillary sinus tumors were 91% more likely to survive (hazard ratio [HR]: 0.094, 95% confidence interval [CI]: 0.011–0.78, p = 0.011). Patients with higher‐stage disease stage had worse OS (stage IVb‐c vs. III‐IVa, p = 0.05). All three patients who were alive with no evidence of disease received induction chemotherapy.

Conclusion

For patients with sinonasal NUT carcinoma, the median survival was 15 months but better with lower‐stage and maxillary tumors. Induction chemotherapy may be beneficial.
The effect of aspirin and eicosapentaenoic acid on urinary biomarkers of prostaglandin E2 synthesis and platelet activation in participants of the seAFOod polyp prevention trial
Authors: Sun Ge , Fuller Harriett , Fenton Hayley , Race Amanda D. , Downing Amy , Williams Elizabeth A. , Rees Colin J. , Brown Louise C. , Loadman Paul M. , Hull Mark A.
Published: October 2023

Urinary prostaglandin (PG) E metabolite (PGE‐M) and 11‐dehydro (d)‐thromboxane (TX) B2 are biomarkers of cyclooxygenase‐dependent prostanoid synthesis. We investigated (1) the effect of aspirin 300 mg daily and eicosapentaenoic acid (EPA) 2000 mg daily, alone and in combination, on urinary biomarker levels and, (2) whether urinary biomarker levels predicted colorectal polyp risk, during participation in the seAFOod polyp prevention trial. Urinary PGE‐M and 11‐d‐TXB2 were measured by liquid chromatography‐tandem mass spectrometry. The relationship between urinary biomarker levels and colorectal polyp outcomes was investigated using negative binomial (polyp number) and logistic (% with one or more polyps) regression models. Despite wide temporal variability in PGE‐M and 11‐d‐TXB2 levels within individuals, both aspirin and, to a lesser extent, EPA decreased levels of both biomarkers (74% [P ≤ .001] and 8% [P ≤ .05] reduction in median 11‐d‐TXB2 values, respectively). In the placebo group, a high (quartile [Q] 2‐4) baseline 11‐d‐TXB2 level predicted increased polyp number (incidence rate ratio [IRR] [95% CI] 2.26 [1.11,4.58]) and risk (odds ratio [95% CI] 3.56 [1.09,11.63]). A low (Q1) on‐treatment 11‐d‐TXB2 level predicted reduced colorectal polyp number compared to placebo (IRR 0.34 [0.12,0.93] for combination aspirin and EPA treatment) compared to high on‐treatment 11‐d‐TXB2 values (0.61 [0.34,1.11]). Aspirin and EPA both inhibit PGE‐M and 11‐d‐TXB2 synthesis in keeping with shared in vivo cyclooxygenase inhibition. Colorectal polyp risk and treatment response prediction by 11‐d‐TXB2 is consistent with a role for platelet activation during early colorectal carcinogenesis. The use of urinary 11‐d‐TXB2 measurement for a precision approach to colorectal cancer risk prediction and chemoprevention requires prospective evaluation.
Association between COVID‐19 and vaccination on menstrual cycle
Authors: Marcelino Ana C. , Fim Alana B. , da Cunha Pereira Paula , Monteiro Ilza , Darney Blair G. , Bahamondes Luis
Published: October 2023

Objective

To evaluate changes in the menstrual pattern of women of reproductive age infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) or vaccinated against coronavirus disease 2019 (COVID‐19).

Methods

A cross‐sectional study at the University of Campinas, Brazil using Google questionnaire applied from December 2021 through February 2022, disseminated through snowball technique. Participants responded about characteristics of their menstrual cycle before the pandemic and before COVID‐19 vaccination, and then about characteristics of their cycle 3 months after infection with SARS‐CoV‐2 and 3 months after vaccination. Our primary outcome was a binary indicator of changes in the menstrual cycle. We used multivariate regression analysis to identify factors associated with menstrual changes.

Results

We received 1012 completed questionnaires and 735 (72.7%) were from women aged between 20 and 39 years, 745 (73.6%) were White and 491 (48.6%) lived with a partner. A total of 419 (41.6%) of the women reported SARS‐CoV‐2 infection; however, only two of them were hospitalized, and 995 (98.8%) of women had at least one dose of COVID‐19 vaccine. About menstrual characteristics, 170 (41.3%) reported changes after having COVID‐19 and 294 (29.9%) after COVID‐19 vaccination, respectively. Few years of schooling, lower income, and non‐white ethnicity were related to higher reports of menstrual changes after COVID‐19. Menstrual changes after COVID‐19 vaccination were associated with not using contraception. Higher body mass index was associated with irregularities in cyclicity and bleeding days, after COVID‐19 and COVID‐19 vaccination, respectively.

Conclusion

Our results corroborated the stability of the menstrual cycle after having COVID‐19 or COVID‐19 vaccination; however, there is a potential relationship between menstrual changes and socioeconomic factors as well as contraceptive use.
The effect of socioeconomic status on adverse obstetric and perinatal outcomes in women with polycystic ovary syndrome—An evaluation of a population database
Authors: Hochberg Alyssa , Badeghiesh Ahmad , Baghlaf Haitham , Tseva Ayellet Tzur , Dahan Michael H.
Published: October 2023

Objective

To evaluate the modifying effect of low socioeconomic status (SES) on polycystic ovary syndrome (PCOS) women's pregnancy and neonatal complications.

Methods

A retrospective population‐based cohort study including all women with an ICD‐9 diagnosis of PCOS in the US between 2004 and 2014, who delivered in the third trimester or had a maternal death. SES was defined according to the total annual family income quartile for the entire population studied. We compared women in the lowest income quartile (<$39 000 annually) to those in the higher income quartiles combined (≥$39 000 annually). Pregnancy, delivery, and neonatal outcomes were compared between the two groups.

Results

Overall, 9 096 788 women delivered between 2004 and 2014, of which 12 322 had a PCOS diagnosis and evidence of SES classification. Of these, 2117 (17.2%) were in the lowest SES group, and 10 205 (82.8%) were in the higher SES group. PCOS patients in the lowest SES group, compared to the higher SES group, were more likely to be younger, obese (body mass index ≥30 kg/m2), to have smoked tobacco during pregnancy, and to have chronic hypertension and pregestational diabetes mellitus (DM) (P < 0.05). In a multivariate logistic regression, women in the lowest SES group, compared to the higher SES group, had increased odds of pregnancy‐induced hypertension (aOR 1.27, 95% CI: 1.12–1.46, P < 0.001), pre‐eclampsia (aOR 1.37, 95% CI: 1.14–1.65, P < 0.001), and cesarean delivery (aOR 1.21, 95% CI: 1.09–1.34, P < 0.001), with other comparable pregnancy, delivery and neonatal outcomes.

Conclusion

In PCOS patients, low SES increases the risk for pregnancy‐induced hypertension, pre‐eclampsia and CD, highlighting the importance of diligent pregnancy follow‐up and pre‐eclampsia prevention in these patients.
Group Interpersonal Psychotherapy for minoritized Head Start mothers with depressive symptoms: A mixed method study
Authors: Palmer Molina Abigail , Palinkas Lawrence , Hernandez Yuliana , Garcia Iliana , Stuart Scott , Sosna Todd , Mennen Ferol E.
Published: October 2023

This study explores minoritized mothers’ experiences in group interpersonal psychotherapy (IPT‐G) and relates their experiences to treatment outcomes. Quantitative and qualitative data were gathered from 26 Latinx and Black mothers who participated in IPT‐G. Mothers were divided into three groups: (1) not depressed at follow‐up, (2) depressed at follow‐up, and (3) those with subclinical symptoms throughout the intervention, and similarities and differences across groups were examined. Results showed that mothers not depressed at follow‐up reported high levels of emotional safety in IPT‐G, facilitating emotional processing. Mothers depressed at follow‐up referenced the impact of stigma and had greater difficulty sharing their feelings and also reported lower socioeconomic status and higher levels of trauma. It appears that high levels of environmental stressors and difficulty developing trusting therapeutic relationships were related to experiencing depression at the conclusion of treatment. Alternatively, for many mothers, IPT‐G provided within head start was an effective therapeutic option.