bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation of Spin‐Induced Ferroelectricity in a Layered van der Waals Antiferromagnet CuCrP2S6
Authors: Park Chang Bae , Shahee Aga , Kim Kwang‐Tak , Patil Deepak R. , Guda Sergey Alexandrovich , Ter‐Oganessian Nikita , Kim Kee Hoon
Published: January 2022

CuCrP2S6, a van der Waals magnet having stacked layers of 2D honeycomb lattice made of CuS3 triangles and CrS6 octahedra, exhibits an A‐type antiferromagnetic order with the Néel temperature (TN) = 32 K. Upon in‐plane magnetic field (H) being applied below TN, H‐induced modulation of the c*‐axis electric polarization (ΔPc*) is found at fields lower than the saturation field µ0HS = 6.1 T, at which a forced ferromagnetic alignment sets in. Based on the symmetry analyses and dependence of ΔPc* on H and the azimuthal angle of applied H direction, a microscopic origin of the magnetoelectric (ME) coupling is attributed to the spin‐direction‐dependent p–d hybridization that is allowed due to the presence of off‐centered Cr3+ octahedra. A comparative study on CuCrP2Se6, however, finds no H‐induced P modulation due to cancellation of P between neighboring layers with the doubling of a crystallographic unit cell at TN. As the p–d hybridization mechanism allows generation of P in a single Cr atom–ligand pair, the results imply that large ME coupling should exist even in a single layer limit of CuCrP2S6.
The p.Thr395Met missense variant of NFIA found in a patient with intellectual disability is a defective variant
Authors: Ogura Yurie , Uehara Tomoko , Ujibe Kota , Yoshihashi Hiroshi , Yamada Mamiko , Suzuki Hisato , Takenouchi Toshiki , Kosaki Kenjiro , Hirata Hiromi
Published: January 2022

Nuclear factor one A (NFIA) is a transcription factor that regulates the development of the central nervous system. Haploinsufficiency of the NFIA gene causes NFIA‐related disorder, which includes brain abnormalities and intellectual disability, with or without urinary tract defects. Intragenic deletions, nonsense variants, frameshift variants, and missense variants in one allele of the NFIA gene have been reported to cause various neurological and urogenital symptoms. Here we report a 10‐year‐old male patient with developmental delay, coarctation of the aorta, and distinctive facial features. Exome analysis identified a rare de novo heterozygous missense variant p.Thr395Met in NFIA. We employed zebrafish as a model organism in our NFIA analysis and found that nfia−/− zebrafish initially showed a loss of commissural axons in the brain, and eventually underwent growth retardation resulting in premature death. Impairment of the commissural neurons in nfia−/− zebrafish embryos could be restored by the expression of wild‐type human NFIA protein, but not of mutant human protein harboring the p.Thr395Met substitution, indicating that this variant affects the function of NFIA protein. Taken together, we suggest that the p.Thr395Met allele in the NFIA gene is relevant to the pathogenesis of NFIA‐related disorder.
Male chimpanzee sexual coercion and mating success at Ngogo
Authors: Watts David P.
Published: January 2022

Chimpanzees (Pan troglodytes) have a complex mating system in which both sexes use multiple tactics. Most copulations occur in group contexts, and high‐ranking males can gain high mating and reproductive success, but females typically mate with multiple males and the potential for sperm competition is high. Also, male‐female dyads sometimes form temporary exclusive mating associations (consortships). Male aggression to receptive females is common. Several studies have supported the hypothesis that this is sexual coercion, but debate exists regarding the importance of coercion relative to that of female choice. The number of adult males in a community can influence the balance between these processes. In the large Ngogo community, male dominance ranks and rates of aggression to fully‐swollen females were positively related to mating success as estimated by copulation rates and by proportions of copulations achieved. Aggression rates were higher than at other sites, overall and per male, especially during periovulatory periods, and increased with the number of males associating with a female. Aggression impaired female foraging efficiency. Males initiated most copulations and females rarely refused mating attempts. Male‐to‐female grooming was positively associated with male mating success and with the proportion of copulations that females initiated, but the amount of grooming was typically small and whether grooming‐for‐mating trading occurs is uncertain. These results are consistent with the hypothesis that sexual coercion is an important component of male chimpanzee mating strategies in many sociodemographic circumstances, but also show that male tactics vary both in response to and independently of those circumstances.
Wellenlängen‐Orthogonale Versteifung von Hydrogel‐Netzwerken mit sichtbarem Licht
Authors: Truong Vinh X. , Bachmann Julian , Unterreiner Andreas‐Neil , Blinco James P. , Barner‐Kowollik Christopher
Published: January 2022

Hierin stellen wir die wellenlängen‐orthogonale Vernetzung von Hydrogelnetzwerken unter Verwendung zweier stark rotverschobener Chromophore vor, nämlich Acrylpyren (AP, λAktivierung=410–490 nm) und Styrylpyrido[2,3‐b]pyrazin (SPP, λAktivierung=400–550 nm), die eine [2+2]‐Photocycloaddition im sichtbaren Wellenlängenbereich eingehen können. Die Photoreaktivität der SPP‐Gruppe ist pH‐abhängig, wobei eine saure Umgebung die Cycloaddition hemmt. Durch den Einsatz eines auf Spiropyran basierenden Photosäuregenerator mit geeigneter Absorptionswellenlänge sind wir in der Lage, die Aktivierungswellenlänge der SPP‐Gruppe auf den grünen Wellenlängenbereich (λAktivierung=520–550 nm) zu beschränken, was eine wellenlängen‐orthogonale Aktivierung der AP‐Gruppe ermöglicht. Unser wellenlängen‐orthogonales photochemisches System wurde erfolgreich zur Entwicklung von Hydrogelen eingesetzt, deren Steifigkeit unabhängig voneinander durch grünes oder blaues Licht eingestellt werden kann.
Wavelength‐Orthogonal Stiffening of Hydrogel Networks with Visible Light
Authors: Truong Vinh X. , Bachmann Julian , Unterreiner Andreas‐Neil , Blinco James P. , Barner‐Kowollik Christopher
Published: January 2022

Herein, we introduce the wavelength‐orthogonal crosslinking of hydrogel networks using two red‐shifted chromophores, i.e. acrylpyerene (AP, λactivation=410–490 nm) and styrylpyrido[2,3‐b]pyrazine (SPP, λactivation=400–550 nm), able to undergo [2+2] photocycloaddition in the visible‐light regime. The photoreactivity of the SPP moiety is pH‐dependent, whereby an acidic environment inhibits the cycloaddition. By employing a spiropyran‐based photoacid generator with suitable absorption wavelength, we are able to restrict the activation wavelength of the SPP moiety to the green light region (λactivation=520–550 nm), enabling wavelength‐orthogonal activation of the AP group. Our wavelength‐orthogonal photochemical system was successfully applied in the design of hydrogels whose stiffness can be tuned independently by either green or blue light.
Relationship between exposure to ionizing radiation and mesothelioma risk: A systematic review of the scientific literature and meta‐analysis
Authors: Visci Giovanni , Rizzello Emanuele , Zunarelli Carlotta , Violante Francesco Saverio , Boffetta Paolo
Published: January 2022

Background

Ionizing radiation and mesothelioma have been examined among personnel employed in nuclear power plant and patients treated by external beam radiation therapy (EBRT). The association is still controversial; the purpose of this review is to summarize the scientific evidence published in the literature regarding the relationship between ionizing radiation and incidence of mesothelioma and, if possible, estimating strongness of the association by meta‐analysis of extracted data.

Methods

Articles included in the systematic review were retrieved by searching among the three main scientific databases: PubMed, Scopus, and Embase. The literature search was conducted in June 2021. A meta‐analysis of random effects was conducted, stratified by exposure (EBRT, occupational exposure). The heterogeneity of the summary relative risks (RRs) was assessed using I2 statistics. Publication bias was evaluated graphically through the funnel plot.

Findings

The exposure to ionizing radiation could be a risk factor for mesothelioma: both for exposure to high doses for short periods (EBRT) (RR of 3.34 [95% confidence interval, CI 1.24–8.99]) and for exposure to low doses for a prolonged duration (exposure working) (RR of 3.57 [95% CI 2.16–5.89]).

Conclusions

Despite the low number of mesotheliomas in the general population, the steadily increased risk among individuals exposed to radiation is still worth considering.
Automatisierte Probenfiltration zur Analyse intrazellulärer Metaboliten bei höheren Biomassekonzentrationen
Authors: Hans Enrico , Zeng An‐Ping
Published: January 2022

Die meisten Stoffwechseluntersuchungen hinsichtlich intrazellulärer Metaboliten für Corynebacterium glutamicum‐Stämme wurden bisher mit Biomassekonzentrationen ≤ 10 g L−1 durchgeführt. Innerhalb der vorliegenden Arbeit konnte gezeigt werden, dass Untersuchungen bis Konzentrationen von 32 g L−1 möglich sind. Die Modifikation einer automatisierten Schnellfiltration weist den Weg zu weiteren zeitlichen Verkürzungen auf. Außerdem konnte mithilfe der Filtration der Einfluss einer genetischen Modifikation der Aspartokinase zur Unterdrückung der Inhibierung im Aspartatstoffwechsel quantifiziert werden.
Nutzung rheologischer Kennwerte zur Beurteilung der Schmierfetteignung bei tiefen Temperaturen
Authors: Hodapp Annika , Conrad Andreas , Hochstein Bernhard , Jacob Karl‐Heinz , Willenbacher Norbert
Published: January 2022

Die Viskosität und die Fließgrenze von Schmierfetten wurde im Bereich von 20 °C bis –40 °C untersucht. Die Temperaturabhängigkeit beider Größen folgt einem Arrhenius‐Gesetz. Die Temperaturabhängigkeit der Viskosität der Grundöle wird durch eine WLF‐Gleichung beschrieben und ist deutlich stärker ausgeprägt. Die Eignung von Schmierfetten wird über die Zugehörigkeit zu einer NLGI‐Klasse beurteilt, die anhand der Eindringtiefe eines Kegels in das Fett bestimmt wird. Dies korreliert eindeutig mit der Fließgrenze und ermöglicht so die temperaturabhängige Zuordnung eines Fettes zu einer NLGI‐Klasse.
Suppressing the shuttle effect in lithium‐sulphur batteries by defective single‐walled ZnO nanotube: A DFT study
Authors: Zou Jiaxuan , Cao Yongan , Zhang Bo , Wang Wenju
Published: January 2022

Lithium‐sulphur batteries are regarded as one of the most potential energy storage systems with high energy density. However, the shuttle effect still limits the development of lithium‐sulphur batteries. The single‐walled zinc oxide nanotube is a one‐dimensional material that can be used as the anchoring material of lithium‐sulphur batteries. In this work, the anchoring performance of pristine single‐walled zinc oxide nanotube and defective single‐walled zinc oxide nanotube to polysulfides were studied by density functional theory, including adsorption energy, charge transfer, the highest occupied molecular orbital, and the lowest unoccupied molecular orbital levels. The results show that a single‐walled zinc oxide nanotube with three oxygen vacancies has the strongest adsorption ability and the highest conductivity. Our work provides a theoretical basis for single‐walled zinc oxide nanotubes to adsorb polysulfides. Single‐walled zinc oxide nanotubes can be used as a potential anchoring material to modify the cathode and separator to improve the cycle stability of lithium‐sulphur batteries.
Safety, Pharmacokinetics, and Pharmacodynamics of Etavopivat (FT‐4202), an Allosteric Activator of Pyruvate Kinase‐R, in Healthy Adults: A Randomized, Placebo‐Controlled, Double‐Blind, First‐in‐Human Phase 1 Trial
Authors: Forsyth Sanjeev , Schroeder Patricia , Geib James , Vrishabhendra Leela , Konstantinidis Diamantis G. , LaSalvia Kari , Ribadeneira Maria D. , Wu Eric , Kelly Patrick , Kalfa Theodosia A.
Published: January 2022

Etavopivat (FT‐4202) is an orally administered, small‐molecule allosteric activator of erythrocyte pyruvate kinase‐R (PKR) in clinical development for the treatment of sickle cell disease and other hemoglobin disorders. This randomized, placebo‐controlled, double‐blind, first‐in‐human combination single‐ascending dose and multiple‐ascending dose phase 1 trial (NCT03815695) evaluated the safety and pharmacokinetics/pharmacodynamics of etavopivat in 90 healthy adult subjects. In 4 single‐ascending dose cohorts, 8 participants were randomized 3:1 to a single oral dose of either etavopivat (n = 6) or placebo (n = 2). In four 14‐day multiple‐ascending dose cohorts, 12 participants were randomized 3:1 to 14 days of etavopivat (n = 9) or placebo (n = 3). In these studies, most treatment‐emergent adverse events were of mild severity (grade 1) and none led to study discontinuation. Etavopivat exhibited a linear and time‐independent pharmacokinetic profile (at doses ≤400 mg) and elicited the expected pharmacodynamic effects of PKR activation (decreased 2,3‐diphosphoglycerate and increased adenosine triphosphate) and evidence of improved hemoglobin‐oxygen affinity. In addition, pharmacodynamic responses were durable with effects continuing for 48 to 72 hours after the last dose, thereby supporting once‐daily dosing. Food appeared to have no clinically meaningful effects on etavopivat exposure, thus facilitating administration with or without food. In conclusion, the evaluation of etavopivat in healthy subjects demonstrated proof of mechanism (PKR activation) without significant adverse events. This study also allowed for the selection of dose levels, projected to have an acceptable safety profile and provide therapeutic benefit, for evaluation in future trials in patients with sickle cell disease.
Rare Tautomers of Artificially Expanded Genetic Letters and their Effects on the Base Pair Stabilities
Authors: Jena N. R.
Published: January 2022

In order to expand the existing genetic letters, it is necessary to design robust nucleotides that can function naturally in living cells. Therefore, it is desirable to examine the roles of recently‐proposed second‐generation artificially genetic letters in producing stable duplex DNA. Herein, a reliable dispersion‐corrected density functional theory method is used to shed light on the electronic structures and properties of different rare tautomers of proposed expanded genetic letters and their effects on the base pair stabilities in the duplex DNA. It is found that the rare tautomers are not only stable in the aqueous medium but can also pair with natural bases to produce stable mispairs. Except for J and V, all of the artificial genetic letters are found to produce mispairs that are about 1–7 kcal mol−1 more stable than their complementary counterparts. They are also appreciably more stable than the naturally occurring G : C, A : T, and G : T pairs. Mainly attractive electrostatic interactions and polarity of the monomers are responsible for the higher base pair stabilities.
Nitrification and denitrification in the Community Land Model compared with observations at Hubbard Brook Forest
Authors: Nevison Cynthia , Goodale Christine , Hess Peter , Wieder William R. , Vira Julius , Groffman Peter M.
Published: January 2022

Models of terrestrial system dynamics often include nitrogen (N) cycles to better represent N limitations on terrestrial carbon (C) uptake, but simulating the fate of N in ecosystems has proven challenging. Here, key soil N fluxes and flux ratios from the Community Land Model version 5.0 (CLM5.0) are compared with an extensive set of observations from the Hubbard Brook Forest Long‐Term Ecological Research site in New Hampshire. Simulated fluxes include microbial immobilization and plant uptake, which compete with nitrification and denitrification, respectively, for available soil ammonium (NH4+) and nitrate (NO3−). In its default configuration, CLM5.0 predicts that both plant uptake and immobilization are strongly dominated by NH4+ over NO3−, and that the model ratio of nitrification:denitrification is ~1:1. In contrast, Hubbard Brook observations suggest that NO3− plays a more significant role in plant uptake and that nitrification could exceed denitrification by an order of magnitude. Modifications to the standard CLM5.0 at Hubbard Brook indicate that a simultaneous increase in the competitiveness of nitrifying microbes for NH4+ and reduction in the competitiveness of denitrifying bacteria for NO3− are needed to bring soil N flux ratios into better agreement with observations. Such adjustments, combined with evaluation against observations, may help to improve confidence in present and future simulations of N limitation on the C cycle, although C fluxes, such as gross primary productivity and net primary productivity, are less sensitive to the model modifications than soil N fluxes.
Routinely measured cardiac troponin I and N‐terminal pro‐B‐type natriuretic peptide as predictors of mortality in haemodialysis patients
Authors: Eriguchi Masahiro , Tsuruya Kazuhiko , Lopes Marcelo , Bieber Brian , McCullough Keith , Pecoits‐Filho Roberto , Robinson Bruce , Pisoni Ronald , Kanda Eiichiro , Iseki Kunitoshi , Hirakata Hideki
Published: January 2022

Aims

Cardiac troponin (cTn) and B‐type natriuretic peptide (BNP) are elevated in haemodialysis (HD) patients, and this elevation is associated with HD‐induced myocardial stunning/myocardial strain. However, studies using data from the international Dialysis Outcomes and Practice Patterns Study (DOPPS) have shown that these cardiac biomarkers are measured in <2% of HD patients in real‐world practice. This study aimed to examine whether routinely measured N‐terminal pro‐BNP (NT‐proBNP) and cTnI (contemporary assay) are more appropriate than clinical models for reclassifying the risk of HD patients who have the highest risk of death.

Methods and results

Pre‐dialysis levels of cTnI and NT‐proBNP at study enrolment were measured in 1152 HD patients (Japan DOPPS Phase 5). The patients were prospectively followed for 3 years. Cox regression was used to test the associations of cardiac biomarkers with all‐cause mortality, adjusting for potential confounders. Subgroup analyses were performed to assess potential effect modification of clinical characteristics, such as age, systolic blood pressure, HD vintage, diabetes mellitus, coronary artery disease, and a history of congestive heart failure. At baseline, 337 (29%) patients had elevated cTnI (99th percentile of a healthy population: >0.04 ng/mL) with a median (inter‐quartile range) level of 0.020 (0.005–0.041) ng/mL, and 1140 (99%) patients had elevated NT‐proBNP (cut‐off for heart failure: >125 pg/mL) with a median level of 3658 (1689–9356) pg/mL. There were 167 deaths during a median follow‐up of 2.8 (2.2–2.8) years. Higher levels of both cardiac biomarkers were incrementally associated with mortality after adjustment for potential confounders. Even after adjustment for alternative cardiac biomarkers, the overall P value for the association was <0.01 for both biomarkers. However, the prognostic significance of NT‐proBNP was moderately diminished when cTnI was added to the model. The hazard ratios of mortality for cTnI > 0.04 ng/mL (vs. cTnI < 0.006 ng/mL) and NT‐proBNP > 8000 pg/mL (vs. NT‐proBNP < 2000 pg/mL) were 2.56 (95% confidence interval: 1.37–4.81) and 1.90 (95% confidence interval: 0.95–3.79), respectively. Subgroup analyses showed that the associations of both cardiac biomarkers with mortality were generally consistent between stratified groups.

Conclusions

Routinely measured NT‐proBNP and cTnI levels are strongly associated with mortality among prevalent HD patients. These associations remain robust, even after adjustment for alternative biomarkers, suggesting that cTnI and NT‐proBNP have identical prognostic significance and may reflect different pathological aspects of cardiac abnormalities.
Robustness of outcomes in trials evaluating sodium–glucose co‐transporter 2 inhibitors for heart failure
Authors: Usman Muhammad Shariq , Khan Muhammad Shahzeb , Fonarow Gregg C. , Greene Stephen J. , Friede Tim , Vaduganathan Muthiah , Filippatos Gerasimos , Coats Andrew J. Stewart , Anker Stefan D. , Butler Javed
Published: January 2022

Aims

Recent trials have evaluated sodium–glucose co‐transporter 2 inhibitors in patients with heart failure (HF). We sought to assess the robustness of findings from these trials using the fragility index (FI).

Methods and results

Fragility index is defined as the minimum number of patients that must be moved from the ‘non‐event’ to the ‘event’ group to turn a statistically significant result to non‐significant. In addition to FI, fragility quotient [(FQ); FI divided by the sample size] was calculated to assess the proportion of events that must be moved to change the significance. For statistically non‐significant outcomes, reverse fragility index (RFI) and reverse fragility quotient (RFQ) were calculated. Robustness of findings after pooling data from all three trials was also assessed. A robust reduction in first HF hospitalization or cardiovascular mortality was seen with dapagliflozin (FI = 62 and FQ = 0.013), empagliflozin (FI = 50 and FQ = 0.013), and sotagliflozin (FI = 60 and FQ = 0.049). Dapagliflozin nominally improved all‐cause and cardiovascular mortality, with modest FI (n = 8 and 5) and FQ (0.002 and 0.001). Empagliflozin and sotagliflozin did not demonstrate statistically significant reductions in all‐cause mortality, with modest RFI (empagliflozin: RFI = 26 and RFQ = 0.007; sotagliflozin: RFI = 6 and RFQ = 0.005). A similar trend was seen with cardiovascular mortality (empagliflozin: RFI = 24 and RFQ = 0.006; sotagliflozin: RFI = 7 and RFQ = 0.006). Upon meta‐analysis, the result for first HF hospitalization or cardiovascular mortality was robust (FI = 95 and FQ = 0.010). The reductions in all‐cause (FI = 12 and FQ = 0.001) and cardiovascular mortality (FI = 9 and FQ = 0.001), while statistically significant, were fragile.

Conclusion

Improvement in the composite outcome of first HF hospitalization or cardiovascular death was highly concordant and robust across sodium–glucose co‐transporter 2 inhibitor trials. In contrast, secondary endpoints of all‐cause and cardiovascular mortality were statistically fragile, underscoring the need to power trials for mortality to fully understand the benefit of therapies on fatal events.
New Hypercoordinating Organostannanes for the Modular Functionalization of Mono‐ and Polystannanes: Synthetic and Computational Studies**
Authors: Pau Jeffrey , Choi Jung‐Won , Silverthorne Kaitlyn , Ranne Mokhamed , Wylie R. Stephen , Gossage Robert A. , Lough Alan J. , Foucher Daniel A.
Published: January 2022

A series of potentially hypercoordinate tin compounds derived from a substitutionally labile tosyl stannane (5) was produced to gain access to a library of propyloxybiphenyl (11), propylmethoxy (12, 14, 18, 22) or propylthioester (13, 15, 19, 23) stannanes for structure/property/polymerization investigations. Structural characterizations by single crystal X‐ray diffraction of 12, 14, 18 and 19 were also undertaken. The relative energies of hypercoordinate conformers for the propylmethoxystannanes 12, 14, 18, and 22 were determined with DFT methods and the fractional abundance of conformers in the gas and solution (CHCl3) phase were estimated. Relativistic DFT calculations of 119Sn NMR chemical shifts were carried out for a series of non‐hypercoordinate reference compounds and the conformers, allowing the estimation of Boltzmann‐averaged chemical shifts of the hypercoordinate propylmethoxystannanes. A semi‐crystalline homopolymer (25) was isolated from the dehydropolymerization of 22 using Wilkinson's catalyst. Conversion of the liable tosylated polystannane (24) to a new partially substituted polystannane (28) via nucleophile displacement reactions was achieved.
Improvement of Luminescence Characteristics of ZnGa2O4:Tb3+ Nanophosphors by Ce3+ Codoping
Authors: Mu Boshi , Zhao Feng , Chu Yunting , Li Chengren , Sun Jingchang , Zhao Qianyun , Bai Suyuan
Published: January 2022

A series of ZnGa2O4:Tb3+,Ce3+ persistent luminescence nanophosphors were prepared by high temperature solid‐state reaction. The X‐ray diffraction (XRD) patterns of the representative samples are consistent with that of the ZnGa2O4 standard card. Scanning electron microscope (SEM) images show that the particle size of phosphor is enlarged when the Tb3+ ion is doped, however, it becomes smaller again after the Ce3+ ion is codoped. For ZnGa2O4:Tb3+ nanophosphors, there exist intense 492 and 551 nm blue/green emissions under 280 nm excitation, and the optimum Tb3+ doping concentration is 1.7 mol% and the long afterglow time is about 140 min. The PL and long afterglow characteristics of ZnGa2O4:1.7Tb3+ nanophosphor are significantly improved once the Ce3+ ion is codoped. The PL intensity of ZnGa2O4:1.7Tb3+ nanophosphor is enhanced by 1.5 times and the long afterglow time is extended to 210 min when Ce3+ doping concentrations are 0.3 and 0.5 mol%, respectively. The internal mechanism of the long afterglow effect of ZnGa2O4:1.7Tb3+,0.5Ce3+ nanophosphor is discussed in detail with the help of measurement results of thermoluminescence spectra.
Metalation of Aryl‐bis(3‐alkyl‐5‐methylpyrazol‐1‐yl)‐ methane (Alkyl=Me, Ad; Aryl=Ph, C6H4‐2−OH) with NaN(SiMe3)2, KN(SiMe3)2, and Ca{N(SiMe3)2}2
Authors: Mandel Miles J. , Müller Christoph , Görls Helmar , Krieck Sven , Westerhausen Matthias
Published: January 2022

Deprotonation of phenyl‐bis(3,5‐dimethylpyrazolyl)methane (HC(Ph)(PzMe2)2, 1 a) with [(thf)2Ca{N(SiMe3)2}2] in THF at −40 °C yields heteroleptic [(thf)2Ca{N(SiMe3)2}{C(Ph)(PzMe2)2}] (2 a) and finally homoleptic [(thf)Ca{C(Ph)(PzMe2)2}2] (2 b). However, these complexes degrade at room temperature to calcium bis(pyrazolate) and 2‐phenyl‐4,6‐dimethylpyrimidine (3 a). This degradation is accelerated when bulky phenyl‐bis(3‐adamantyl‐5‐methylpyrazolyl)methane (HC(Ph)(PzAd,Me)2, 1 b) is treated similarly and 2‐phenyl‐4‐adamantyl‐6‐methylpyrimidine (3 b) forms quickly. Sodiation of 1 a and 1 b with NaN(SiMe3)2 yields [{HC(Ph)(PzMe2)2}Na{C(Ph)(PzMe2)2}] (4 a) and [{HC(Ph)(PzAd,Me)2}Na{C(Ph)(PzAd,Me)2}] (4 b). The stronger metalation reagent benzylpotassium is able to quantitatively deprotonate 1 b leading to dinuclear [K{C(Ph)(PzAd,Me)2}]2 (4 c). The metathetical approach and the reaction of 4 c with metal(II) halides of Mg, Ca and Zn again leads to degradation and formation of pyrimidine 3 b. This decomposition of the ligand can be circumvented when the sidearm contains the anionic charge. Thus, 2‐hydroxyphenyl‐bis(3‐adamantyl‐5‐methylpyrazol‐1‐yl)methane (1 c) reacts with [(thf)2Ca{N(SiMe3)2}2] in THF to the homoleptic complex [(thf)4Ca{O−C6H4−CH(PzAd,Me)2}] (2 c). In this complex, THF and pyrazolyl bases compete in the coordination sphere and preparation of a heteroleptic complex fails. To avoid the binding competition between THF and pyrazolyl bases and to stabilize heteroleptic calcium complexes, the reaction has been repeated in toluene yielding [Ca{N(SiMe3)2}{O−C6H4−CH(PzAd,Me)2}]2 (2 d).
On the Synthesis of a T‐Shaped Imido Nickel Complex and Trigonal Amido Nickel Complexes
Authors: Reckziegel Alexander , Battistella Beatrice , Werncke C. Gunnar
Published: January 2022

The synthesis of a T‐shaped imido nickel complex is reported, obtained by the reaction of phenyl azide with the linear nickel(I) silylamide complex K{18‐crown‐6}[NiL2] (L=−N(Dipp)SiMe3; Dipp=2,6‐diisopropylphenyl). In addition, an unusual shift of a SiMe3 unit from an ancillary ligand to a putative [Ni=NPh] complex is observed. Examination of the resulting [Ni=NDipp] complex for its electronic properties leads to its description as a low‐spin nickel(III) imide and revealed only limited activity with respect to H‐atom abstraction from C−H bonds or nitrene. Attempts to obtain information about the general features of trigonal nickel(II) amide products, that would result from such a H‐atom abstraction reaction, via reaction of linear nickel(II) silylamide [NiL2] with alkali metal salts of primary amides revealed the reduction to the linear nickel(I) complex K{18‐crown‐6}[NiL2]. The same is observed for alkoxides, secondary amides or benzyl. Reaction of the organic salts with the anionic nickel(II) complex NBu4[NiBrL2] under salt elimination also give the linear nickel(I) complex. Partial formation of an otherwise stable T‐shaped nickel(II) can be observed only for the electron‐poor diphenyl amide. This implicates that reduction of the starting nickel(II) complexes by different organic alkali metal salts likely does not occur via a homolytic Ni−R bond cleavage but a direct SET process from the unligated substrate to the nickel(II) ion.
Dynamic simulation of a solar ejector‐based trigeneration system using TRNSYS‐EES co‐simulator
Authors: Pourmoghadam Peyman , Jafari Mosleh Hassan , Karami Maryam
Published: January 2022

In this paper, a new configuration of a solar combined cooling, heating, and power (CCHP) system is proposed to recover the waste thermal energy of a steam power plant, which provides the cooling and heating needs of an apartment complex located in Tehran. The required energy of the system is supplied by the parabolic trough solar collectors (PTCs) and, if necessary, an auxiliary heater is also used. An ejector refrigeration cycle (ERC) and a steam Rankine cycle are used for cooling and power generation, respectively. The cycle is dynamically modeled over a year using a TRNSYS‐EES co‐simulator. It is found that the highest Rankine cycle efficiency is obtained in the cold months (January) because of the decrease of turbine backpressure. With increasing the turbine inlet temperature from 190 to 210°C, the Rankine cycle and the overall cycle efficiencies increased about 1% and 2%, respectively. The maximum cooling, heating, and power generation, as well as the maximum solar fraction, are obtained at the turbine inlet temperatures of 210°C, which are 185.46, 598.65, 680.49 kW, and 70%, respectively. The annual overall performance and the solar fraction of the proposed CCHP system are 32.5% and 9.5%, respectively, based on 3000 m2 collector aperture area. The exergy analysis indicated that the maximum annual exergy destruction is related to the solar collectors, which have comprised 27% of the total exergy destruction. In addition, the yearly exergy efficiency of the proposed system is 39.9%.
Data‐driven identification of the spatiotemporal structure of turbulent flows by streaming dynamic mode decomposition
Authors: Yang Rui , Zhang Xuan , Reiter Philipp , Lohse Detlef , Shishkina Olga , Linkmann Moritz
Published: January 2022

Streaming Dynamic Mode Decomposition (sDMD) is a low‐storage version of dynamic mode decomposition (DMD), a data‐driven method to extract spatiotemporal flow patterns. Streaming DMD avoids storing the entire data sequence in memory by approximating the dynamic modes through incremental updates with new available data. In this paper, we use sDMD to identify and extract dominant spatiotemporal structures of different turbulent flows, requiring the analysis of large datasets. First, the efficiency and accuracy of sDMD are compared to the classical DMD, using a publicly available test dataset that consists of velocity field snapshots obtained by direct numerical simulation of a wake flow behind a cylinder. Streaming DMD not only reliably reproduces the most important dynamical features of the flow; our calculations also highlight its advantage in terms of the required computational resources. We subsequently use sDMD to analyse three different turbulent flows that all show some degree of large‐scale coherence: rapidly rotating Rayleigh–Bénard convection, horizontal convection and the asymptotic suction boundary layer (ASBL). Structures of different frequencies and spatial extent can be clearly separated, and the prominent features of the dynamics are captured with just a few dynamic modes. In summary, we demonstrate that sDMD is a powerful tool for the identification of spatiotemporal structures in a wide range of turbulent flows.
Cholangiocarcinoma progression depends on the uptake and metabolization of extracellular lipids
Authors: Ruiz de Gauna Mikel , Biancaniello Francesca , González‐Romero Francisco , Rodrigues Pedro M. , Lapitz Ainhoa , Gómez‐Santos Beatriz , Olaizola Paula , Di Matteo Sabina , Aurrekoetxea Igor , Labiano Ibone , Nieva‐Zuluaga Ane , Benito‐Vicente Asier , Perugorria María J. , Apodaka‐Biguri Maider , Paiva Nuno A. , Sáenz de Urturi Diego , Buqué Xabier , Delgado Igotz , Martín César , Azkargorta Mikel , Elortza Felix , Calvisi Diego F. , Andersen Jesper B. , Alvaro Domenico , Cardinale Vincenzo , Bujanda Luis , Banales Jesús M. , Aspichueta Patricia
Published: January 2022

Background and Aims

Cholangiocarcinoma (CCA) includes a heterogeneous group of biliary cancers with a dismal prognosis. We investigated if lipid metabolism is disrupted in CCA and its role in tumor proliferation.

Approach and Results

The in vitro and in vivo tumorigenic capacity of five human CCA cell lines was analyzed. Proteome, lipid content, and metabolic fluxes were evaluated in CCA cells and compared with normal human cholangiocytes (NHC). The Akt1/NOTCH1 intracellular cytoplasmic domain (Nicd1)‐driven CCA mouse model was also evaluated. The proteome of CCA cells was enriched in pathways involved in lipid and lipoprotein metabolism. The EGI1 CCA cell line presented the highest tumorigenic capacity. Metabolic studies in high (EGI1) versus low (HUCCT1) proliferative CCA cells in vitro showed that both EGI1 and HUCCT1 incorporated more fatty acids (FA) than NHC, leading to increased triglyceride storage, also observed in Akt1/Nicd1‐driven CCA mouse model. The highly proliferative EGI1 CCA cells showed greater uptake of very‐low‐density and HDLs than NHC and HUCCT1 CCA cells and increased cholesteryl ester content. The FA oxidation (FAO) and related proteome enrichment were specifically up‐regulated in EGI1, and consequently, pharmacological blockade of FAO induced more pronounced inhibition of their tumorigenic capacity compared with HUCCT1. The expression of acyl‐CoA dehydrogenase ACADM, the first enzyme involved in FAO, was increased in human CCA tissues and correlated with the proliferation marker PCNA.

Conclusions

Highly proliferative human CCA cells rely on lipid and lipoprotein uptake to fuel FA catabolism, suggesting that inhibition of FAO and/or lipid uptake could represent a therapeutic strategy for this CCA subclass.
One‐year changes in the prevalence and positive psychological correlates of depressive symptoms during the COVID‐19 pandemic among medical science students in northeast of Iran
Authors: Mirhosseini Seyedmohammad , Grimwood Samuel , Dadgari Ali , Basirinezhad Mohammad Hasan , Montazeri Rasoul , Ebrahimi Hossein
Published: January 2022

Objectives

The COVID‐19 pandemic has imposed a significant psychological burden on many across society especially students studying medical sciences. This study intended to investigate the one‐year changes in the prevalence and correlates of depressive symptoms during the COVID‐19 pandemic among medical science students.

Methods

A cross‐sectional study in Shahroud, Iran administering a convenience sampling method (January to February 2021). Online self‐reported questionnaires included Rosenberg Self‐Esteem Scale, Paloutzian‐Ellison Spiritual Well‐Being Questionnaire, Diener's Satisfaction with Life Scale and the University Student Depression Inventory. Data analyzed using descriptive and inferential statistics (Independent t‐test and Multiple Regression Analysis).

Results

A total of 306 medical science students were investigated in this study. The mean scores 1 year after the outbreak of COVID‐19 were for depression (81.25 ± 26.04), spiritual well‐being (80.98 ± 18.06), self‐esteem (26.89 ± 2.20), and life satisfaction (19.68 ± 6.81). The results indicated that depression mean score was significantly higher in post outbreak assessment (71.92 ± 22.94 vs 81.25 ± 26.04) (P < .001). Fifty percentage of changes in depression can be predicted by studied variables. A high score of depression was directly associated with a higher level of self‐esteem. Moreover, increased interest in the field, scores of spiritual well‐being, and life satisfaction were inversely and significantly associated with depression.

Conclusions

Iran's education system has been significantly affected, with the addition to the COVID‐19 pandemic imposing a psychological burden such as depression, exacerbating this within medical science students compared to a year ago. Spiritual well‐being and life satisfaction as positive psychology constructs were recognized as protective factors against depression during the pandemic. Spiritual and social support should be integrated in psychological interventions within university settings for medical science students.
On hamiltonian line graphs of hypergraphs
Authors: Gu Xiaofeng , Lai Hong‐Jian , Song Sulin
Published: January 2022

A graph is supereulerian if it has a spanning eulerian subgraph. Harary and Nash‐Williams in 1968 proved that the line graph of a graph is hamiltonian if and only if has a dominating eulerian subgraph, Jaeger in 1979 showed that every 4‐edge‐connected graph is supereulerian, and Catlin in 1988 proved that every graph with two edge‐disjoint spanning trees is a contractible configuration for supereulerianicity. Utilizing the notion of partition‐connectedness of hypergraphs introduced by Frank, Király, and Kriesell in 2003, we generalize the above‐mentioned results of Harary and Nash‐Williams, of Jaeger and of Catlin to hypergraphs by characterizing hypergraphs whose line graphs are hamiltonian, and showing that every 2‐partition‐connected hypergraph is a contractible configuration for supereulerianicity.
Recognizing interval bigraphs by forbidden patterns
Authors: Rafiey Arash
Published: January 2022

Let be a connected bipartite graph with vertices and edges. We give an time algorithm to decide whether is an interval bigraph. The best known algorithm has time complexity and it was developed by Muller in 1997. Our approach is based on an ordering characterization of interval bigraphs introduced by Hell and Huang in 2003. We transform the problem of finding the desired ordering to choosing strong components of a pair‐digraph without creating conflicts. We make use of the structure of the pair‐digraph as well as decomposition of bigraph based on the special components of the pair‐digraph. This way we make explicit what the difficult cases are and gain efficiency by isolating such situations.
Liver volume based prediction model for patients with hepatitis B virus‐related acute‐on‐chronic liver failure
Authors: Hu Chunhua , Jiang Na , Zheng Jie , Li Chenxia , Huang Huihong , Li Juan , Li Hongbing , Gao Zhijie , Yang Nan , Xi Qi , Wang Jing , Liu Zitong , Rao Kemeng , Zhou Heping , Li Tianhui , Chen Yi , Zhang Yuelang , Yang Jian , Zhao Yingren , He Yingli
Published: January 2022

Background

Hepatitis B virus‐related acute‐on‐chronic liver failure (HBV‐ACLF) is a life‐threatening disease with high short‐term mortality. Early and accurate prognosis is significant for clinical decisions, in which liver volume (LV) imparts important information. However, LV has not been considered in current prognostic models for HBV‐ACLF.

Methods

Three hundred and twenty‐three patients were recruited to the deriving cohort, while 163 were enrolled to validation cohort. The primary end‐point was death within 28 days since admission. Estimated liver volume (ELV) was calculated by the formula based on healthy population. Logistic regression was used to develop a prediction model. Accuracy of models were evaluated by receiver operating characteristic (ROC) curves.

Results

The ratio of LV to ELV (LV/ELV%) was significantly lower in non‐survivors, and LV/ELV% ≤82% indicated poor prognosis. LV/ELV%, Age, prothrombin time (PT), the grade of hepatic encephalopathy (HE), ln‐transformed total bilirubin (lnTBil), and log‐transformed HBV DNA (Log10 HBV DNA) were identified as independent predictors to develop an LV‐based model, LEAP‐HBV. The mean area under the ROC (AUC) of LEAP‐HBV was 0.906 (95% CI, 0.904‐0.908), higher than other non‐LV‐based models.

Conclusion

Liver volume was an independent predictor, and LEAP‐HBV, a prediction model based on LV, was developed for the short‐term mortality in HBV‐ACLF.

This study was registered on ClinicalTrails (NCT03977857).
Late Pleistocene glaciation history of the southern Black Forest, Germany: 10Be cosmic‐ray exposure dating and equilibrium line altitude reconstructions in Sankt Wilhelmer Tal
Authors: Hofmann Felix Martin , Preusser Frank , Schimmelpfennig Irene , Léanni Laëtitia , Aster team (Georges Aumaître, Karim Keddadouche & Fawzi Zaid
Published: January 2022

During the Late Pleistocene, an ice cap temporarily rested on the highest summit of the Black Forest, Feldberg, and on the surrounding region. Moraines inside the last glaciation maximum ice extent document subsequent glacial standstills and/or re‐advances, but the chronology of the deglaciation remains largely unknown. In Sankt Wilhelmer Tal, moraines were mapped, and suitable moraine boulders were sampled for 10Be cosmic ray exposure (CRE) dating. Equilibrium line altitudes (ELAs) during moraine formation were reconstructed to evaluate whether these can be used for local stratigraphical correlations. Geomorphological mapping revealed numerous ice‐marginal positions in the main valley and in two tributary valleys. CRE ages and ELAs indicate two discrete phases of glacial standstills and/or re‐advances by 17–16 ka at the latest and no later than 14 ka, respectively. Differing ELAs across the study area preclude the use of ELAs for local stratigraphical correlations. Recalculated 10Be CRE ages from other localities in Central Europe indicate similar periods of moraine formation, thus raising the question of a common climatic forcing. Additional sets of CRE ages are needed to answer this question. In addition, future studies should concentrate on determining the age of the last glaciation maximum in the Black Forest.
Application of a novel nylon needle filter‐based solid‐phase extraction device to determination of 1‐hydroxypyrene in urine
Authors: Yue Shi‐Wen , Zhou Yi‐Lian , Peng Xi‐Tian , Zhao Qin
Published: January 2022

In this work, a simple and miniaturized solid‐phase extraction device was constructed by connecting a commercial nylon needle filter to a syringe, which was applied for extracting 1‐hydroxypyrene from a urine sample via hydrophobic and hydrogen bond interactions. The nylon membrane in the needle filter acted as the solid‐phase extraction adsorbent, meanwhile, it filtered the particles in the urine sample. To obtain high extraction efficiency, key parameters influencing extraction recovery were investigated. The entire pretreatment process was accomplished within 5 min under the optimal conditions. By coupling high‐performance liquid chromatography–ultraviolet, a rapid, low‐cost, and convenient nylon needle filter‐based method was established for the analysis of 1‐hydroxypyrene in a complex urine matrix. Within the linearity range of 0.2–1000 μg/L, the method exhibited a satisfactory correlation coefficient (R = 0.9999). The limit of detection was 0.06 μg/L, and the recoveries from urine sample spiked with three concentrations (5, 20, and 100 μg/L) ranged from 105.8% to 113.1% with the relative standard deviations less than 6.7% (intra‐day, n = 6) and 8.9% (inter‐day, n = 4). Finally, the proposed method was successfully applied for detecting 1‐hydroxypyrene in urine samples from college students, smokers, gas station workers, and chip factory workers. The detected concentration in actual urine samples ranged from 0.46 to 5.26 μg/L. Taken together, this simple and cost‐effective nylon needle filter‐based solid‐phase extraction device showed an excellent application potential for pretreating hydrophobic analytes from aqueous samples.
Animal‐defined resources reveal nutritional inadequacies for woodland caribou during summer–autumn
Authors: Denryter Kristin , Cook Rachel C. , Cook John G. , Parker Katherine L.
Published: January 2022

Populations of woodland caribou (Rangifer tarandus caribou) are declining throughout their range and many are at risk of extirpation, yet the role of nutrition in these declines remains poorly understood, in part owing to a lack of information about available nutritional resources during summer. We quantified rates of intake of digestible protein and digestible energy by tame caribou foraging in temporary enclosures in the predominant plant communities of northeastern British Columbia, Canada, during summer–autumn and compared intake rates to daily requirements for protein and energy during lactation. We tested hypotheses related to the nutritional adequacy of the environment to support nutritional requirements during lactation (with and without replenishment of body reserves) and simulated scenarios of foraging by caribou in these plant communities to better understand how wild caribou could meet nutritional demands on these landscapes. Nutritional resources varied among plant communities across seasonal, ecological, and successional gradients; digestible energy intake per minute and per day were significantly greater in younger than older forests; dietary digestible energy and per‐minute and daily intake of digestible protein were greater, though not significantly so, in younger than older forests; and dietary digestible protein was greater in older than younger forests, though differences were not significant. Tame caribou were unable to satisfy protein and energy requirements during lactation, even without replenishment of body reserves, at most sites sampled. Further, foraging simulations suggested widespread nutritional inadequacies on ranges of wild caribou. Selection for habitats offering the best nutrition may mitigate some nutritional inadequacies, but given low availability of vegetation communities with high nutritional value, performance (e.g., calf production, growth, replenishment of body fat and protein) of caribou may be depressed at levels of nutrition documented herein. Our results, coupled with recent measurements of body fat of wild caribou in northeastern British Columbia, refute the hypothesis that the nutritional environment available to caribou during summer in northeastern British Columbia is adequate to fully support nutritional demands of lactating caribou, which has implications to productivity of caribou populations, recovery, and conservation.
Rethinking Touch HMI Controls for Automotive Displays and Smart Surfaces
Authors: Klein Kevin
Published: January 2022

Solid‐state haptic technology enables novel HMI interactions while delivering safety benefits, cost savings, and multisensory brand differentiation.