bluuebunny/crossref_metadata_2025_split huggingface dataset:
Salt tolerance in a neotropical orchid in the absence of local adaptation to salt spray
Authors: de Lima Thales M. , Silva Simone F. , Ribeiro Rafael V. , Sánchez‐Vilas Julia , Pinheiro Fabio 
Published: July 2024

AbstractPremiseSalt tolerance has rarely been investigated regionally in the neotropics and even more rarely in Orchidaceae, one of the largest families. Therefore, investigating local adaptation to salt spray and its physiological basis in Epidendrum fulgens, a neotropical orchid species, brings important new insights.MethodsWe assessed the degree of salt tolerance in E. fulgens by testing whether coastal populations are more tolerant to salt, which could point to local adaptation. To understand the physiological basis of such salt tolerance, we exposed wild‐collected individuals to salt spray for 60 days, then measured leaf expansion, osmotic potential, sodium leaf concentration, chlorophyll leaf index, chlorophyll fluorescence, relative growth rate, and pressure–volume curves.ResultsThere is no local adaptation to salt spray since both inland and coastal plants have a high tolerance to salt stress. This tolerance is explained by the ability to tolerate high concentrations of salt in leaf tissues, which is related to the high succulence displayed by this species.ConclusionsWe showed an unprecedented salt tolerance level for an orchid species, highlighting our limited knowledge of that trait beyond the traditional studied groups. Another interesting finding is that salt tolerance in E. fulgens is linked to succulence, is widespread, and is not the result of local adaptation. We suggest that E. fulgens and its allied species could be an interesting group to explore the evolution of important traits related to tolerance to salt stress, like succulence.
Benign and Selective Amination of Lignins towards Aromatic Biobased Building Blocks with Primary Amines
Authors: Wybo Nathan , Duval Antoine , Avérous Luc 
Published: July 2024

AbstractLignin is a widely available second‐generation biopolymer and the main potential source of renewable aromatic building blocks. Lignin‐based polyamines offer great potential in applications based on chemical and materials sciences. However, common aminations techniques for lignin usually involve toxic chemicals and generate hindered and low reactivity amines.In this study, we developed two new, simple, and benign 2‐step methodologies for the elaboration of lignin‐based polyamines from different technical lignins (kraft, soda and organosolv) with a selectivity towards reactive primary amines. These methods involve grafting amide groups onto lignin followed by a hydrolysis step. Non‐toxic heterocyclic compounds N‐acetyl‐2‐oxazolidinone and 2‐methyl‐2‐oxazoline were used as amidation agents. Hydrolysis was performed in acetone‐water mixtures. Reactions were studied on model compounds and optimized on lignins. Aminated lignins were fully characterized and primary amines were quantified using quantitative 19F NMR.Our methods generated aminated lignins with low apparent molar masses and high solubility in water and solvents. Nitrogen contents of the products ranged between 2.0 and 3.5 mmol/g with reactive primary amines counts up to 1.7 mmol/g. These soluble and reactive lignin‐based polyamines offer great potential as a replacement for fossil‐based polyamines in e.g., the synthesis of aromatic polymer materials or as potential chelating, antibacterial agents.
Dyotropic Rearrangement of an Iron–Aluminium Complex
Authors: Stadler Benedek , Gorgas Nikolaus , Elliott Stuart J. , Crimmin Mark R. 
Published: July 2024

AbstractLigand exchange processes at metal complexes underpin their reactivity and catalytic applications. While mechanisms of ligand exchange at single site complexes are well established, occurring through textbook associative, dissociative and interchange mechanisms, those involving heterometallic complexes are less well developed. Here we report the reactions of a well‐defined Fe−Al dihydride complex with exogenous ligands (CO and CNR, R=Me, tBu, Xyl=2,6‐Me2C6H3). Based on DFT calculations we suggest that these reactions occur through a dyotropic rearrangement, this involves initial coordination of the exogenous ligand at Al followed by migration to Fe, with simultaneous migration of a hydride ligand from Fe to Al. Such processes are rare for heterometallic complexes. We study the bonding and mechanism of the dyotropic rearrangement through in‐depth computational analysis (NBO, IBOs, CLMO analysis, QTAIM, NCIplot, IGMH), shedding new light on how the electronic structure of the heterometallic core responds to the migration of ligands between metal sites. The dyotropic rearrangement fundamentally changes the nature of the hydride ligands, exposing new nucleophilic reactivity as evidenced by insertion reactions with CO2, isocyanates, as well as isocyanides.
Outstanding Superoxide Dismutase Catalytic Activity Of Simple Peptide‐Based Nickel(II) Complexes
Authors: Guinard Pawel , Hostachy Sarah , Diebold Léa , Pécaut Jacques , Le Goff Alan , Duboc Carole , Delangle Pascale 
Published: July 2024

AbstractWe present here the most active synthetic Ni superoxide dismutase (NiSOD) mimic reported to date. Reactive oxygen species are aggressive compounds, which concentrations are tightly regulated in vivo. Among them, the superoxide anion, O2⋅−, is controlled by superoxide dismutases. Capitalizing on the versatility of the Amino‐Terminal CuII‐ and NiII‐binding (ATCUN) peptide motif, we introduced positive charges around the NiII center to favor the interaction with the superoxide radical anion. At physiological pH, the pentapeptide H−Cys−His−Cys−Arg−Arg−NH2 coordinates NiII after the deprotonation of one thiol, two amides, and either the second thiol or the N‐terminal ammonium, leading to an equilibrium between the two N3S1 and N2S2 coordination modes. Under catalytic conditions, a kcat value of 8.6(4)×106 L.mol−1.s−1 was measured. Within the first second, the catalyst remained undegraded with quantitative consumption of O2⋅− (completed up to 37 catalytic cycles). An extra arginine (Arg) was introduced at the peptide C‐terminus to increase the global charge of the NiII complex from +1 to +2. This had no effect on the catalytic performance, highlighting the critical role of charge distribution in space as a determining factor influencing the reactivity.
Fluorinated Dialkyl Chloronium Salts: Synthesis and Reactivity for Fluoroalkylation and Hydride Abstraction
Authors: Fischer Lukas , Lee Michael H. , Kim Isaac , Wiesner Anja , Hoffmann Kurt F. , Riedel Sebastian 
Published: July 2024

AbstractA new concept for the synthesis of dialkyl chloronium cations [R−Cl−R]+ is described (R=CH3, CH2CF3), that allows the formation of fluorinated derivatives. By utilizing the xenonium salt [XeOTeF5][M(OTeF5)n] (M=Sb, n=6; M=Al, n=4) chlorine atoms of chloroalkanes or the deactivated chlorofluoroalkane CH2ClCF3 are oxidized and removed as ClOTeF5 leading to the isolation of the corresponding chloronium salt. Since the resulting highly electrophilic cation [Cl(CH2CF3)2]+ is able to alkylate weak nucleophiles, this compound can be utilized for the introduction of a fluorinated alkyl group to those. In addition, the fluorinated alkyl chloronium cation displays a high hydride ion affinity, enabling the activation of linear hydrocarbons by hydride abstraction even at low temperatures ultimately leading to the formation of branched carbocations.
Progressive Endergonic Synthesis of Diels–Alder Adducts Driven by Chemical Energy
Authors: Al Shehimy Shaymaa , Le Hai‐Dang , Amano Shuntaro , Di Noja Simone , Monari Luca , Ragazzon Giulio 
Published: July 2024

AbstractThe overwhelming majority of artificial chemical reaction networks respond to stimuli by relaxing towards an equilibrium state. The opposite response—moving away from equilibrium—can afford the endergonic synthesis of molecules, of which only rare examples have been reported. Here, we report six examples of Diels–Alder adducts formed in an endergonic process and use this strategy to realize their stepwise accumulation. Indeed, systems respond to repeated occurrences of the same stimulus by increasing the amount of adduct formed, with the final network distribution depending on the number of stimuli received. Our findings indicate how endergonic processes can contribute to the transition from responsive to adaptive systems.
Silence of Aminopeptidase N 2 gene reveals the trade‐offs for acquiring Cry1Ac resistance in Plutella xylostella
Authors: Lv Zhuohong , Yu Shuwen , Zhao Yafei , Yang Zhongxia 
Published: July 2024

AbstractBacillus thuringiensis (Bt) is widely used as a biopesticide worldwide. To date, at least eight pest species have been found to be resistant to Bt in the field. As the first pest that was reported having resistance to Bt in the field, considerable research has been done on the mechanisms of Bt resistance in Plutella xylostella. However, whether the acquisition of Bt resistance by P. xylostella comes at a fitness cost is also a valuable question. In this study, Aminopeptidase‐N 2 (APN2), a Cry toxin receptor gene of P. xylostella, was knocked down by RNA interference, resulting in improved resistance to Cry1Ac. It was also found that larval mortality of APN2 knockdown P. xylostella was significantly higher than that of the control, while the pupation rate, pupal weight, eclosion rate, fecundity (egg/female), hatchability, and female adult longevity were significantly lower in APN2 knockdown P. xylostella than in the control. These results illustrate that if Cry1Ac resistance was obtained only through the reduction of APN2 expression, P. xylostella would need to incur some fitness costs for it.
Evaluating a sigmoid dark energy model to explain the Hubble tension
Authors: Torres‐Arzayus Sergio , Delgado‐Correal Camilo , Higuera‐G Mario‐Armando , Rueda‐Blanco Sebastián 
Published: July 2024

AbstractIn this study, we analyze Type Ia supernovae (SNe Ia) data sourced from the Pantheon+ compilation to investigate late‐time physics effects influencing the expansion history, , at redshifts . Our focus centers on a time‐varying dark energy (DE) model that introduces a rapid transition in the equation of state, at a specific redshift, , from the baseline, , value to the present value, . The change in the equation of state is implemented as a transition in the DE density scale factor driven by a sigmoid function. The constraints obtained for the DE sigmoid phenomenological parametrization have broad applicability for dynamic DE models that invoke late‐time physics. Our analysis indicates that the sigmoid model provides a slightly better, though not statistically significant, fit to the SNe Pantheon+ data compared to the standard cold dark matter () model. The fit results, assuming a flat geometry and maintaining constant at the 2018‐Planck value of , are as follows: km s Mpc, , . The errors represent statistical uncertainties only. The available SN dataset lacks sufficient statistical power to distinguish between the baseline model and the alternative sigmoid models. A feature of interest offered by the sigmoid model is that it identifies a specific redshift, , where a potential transition in the equation of state could have occurred. The sigmoid model does not favor a DE in the phantom region (). Further constraints to the dynamic DE model have been obtained using CMB data to compute the distance to the last scattering surface. While the sigmoid DE model does not completely resolve the tension, it offers a transition mechanism that can still play a role alongside other potential solutions.
Size of the accretion disc in the recurrent nova T CrB
Authors: Zamanov R. K. , Stoyanov K. A. , Marchev V. , Minev M. , Marchev D. , Moyseev M. , Martí J. , Bode M. F. , Konstantinova‐Antova R. , Stefanov S. 
Published: July 2024

AbstractWe present high‐resolution (0.06 Å px) spectroscopic observations of the recurrent nova T Coronae Borealis obtained during the last 1.5 years (September 2022–January 2024), with the 2.0‐m RCC telescope of the Rozhen National Astronomical Observatory, Bulgaria. Double‐peaked emission is visible in the line after the end of the superactive state. We subtract the red giant contribution and measure the distance between the peaks () of the line. For the period July 2023–January 2024, we find that is in range km s. Assuming that the emission is from the accretion disc around the white dwarf, we find average radius of the accretion disc R, which is approximately equal to the Roche lobe size of the white dwarf. Our results indicate that tidal torque plays an important role but that the disc can extend up to the Roche lobe of the accreting star.
Green and sensitive detection of olopatadine in aqueous humor using a signal‐on fluorimetric approach: GREEnness assessment
Authors: Mostafa Islam M. , Omar Mahmoud A. , Noureldeen Deena A. M. , Zeid Abdallah M. , Halawa Mohamed Ibrahim , Mohamed Abobakr A. 
Published: July 2024

AbstractOlopatadine (OLP) is widely utilized as an effective antihistaminic drug for alleviating ocular itching associated with allergic conjunctivitis. With its frequent usage in pharmacies, there arises a pressing need for a cost‐effective, easily implementable, environmentally sustainable detection method with high sensitivity. This study presents a novel signal‐on fluorimetric method for detecting OLP in both its pure form and aqueous humor. The proposed approach depends on enhancing the weak intrinsic fluorescence emission of OLP, achieving a remarkable increase of up to 680% compared to its intrinsic fluorescence. This enhancement is achieved by forming micelles around protonated OLP using an acetate buffer (pH 3.6) and incorporating a solution of sodium dodecyl sulfate (SDS) surfactant. A strong correlation (R = 0.9996) is observed between the concentration of OLP and fluorescence intensities ranging from 1.0 to 100.0 ng mL−1 with a limit of detection of 0.22 ng mL−1. This described method is successfully employed for quantifying OLP in both its powder form and pharmaceutical eye drops. Furthermore, it demonstrates robust performance in determining OLP in artificial aqueous humor with a percentage recovery of 99.05 ± 1.51, with minimal interference from matrix interferents. Moreover, the greenness of the described method was evaluated.
Consider potential implications of Title IX exemption granted to Baylor University
Authors: Romano Robert , Shanklin Mackenzie 
Published: July 2024

Title IX was originally enacted to protect college students from sex discrimination in educational programs or activities, including athletics. Specifically, Title IX states that “No person in the United States shall, on the basis of sex, be excluded from the participation in, be denied the benefits of, or be subjected to discrimination under any education program or activity receiving Federal financial assistance.” Keep this background information in mind as you read the following about a recent development that occurred in the Title IX arena.
A team of teams creates success from successes
Authors: Skipworth Stan 
Published: July 2024

During the course of a winter break, I had the opportunity to read U.S. Army General (Ret.) Stanley McChrystal's marvelous text, Team of Teams: New Rules of Engagement for a Complex World. In this highly insightful and broadly applicable book for seemingly any industry or genre, General McChrystal outlines the enormous additional value that arises when groups within an organization serve one another while pursuing the overarching mission for the company as a whole.
From Aldehyde to Ketone via Water‐Accelerated Molybdenum‐Photocatalysis
Authors: Meng Jiaolong , Jia Yixin , Li Chengliang , Jiang Xuefeng 
Published: July 2024

AbstractThe efficient “on water” protocol was developed by employing molybdenum‐based polyoxometalate [N(C4H9)4]2[Mo6O19] as the photocatalyst. This water‐accelerated photoinduced process affords versatile ketones from aldehydes straightforwardly, showcasing exceptional substrate generality. Its applicability to life‐related molecules such as amino acids, peptides, and sugars, further demonstrates its potential for bioorthogonal application. The mechanistic investigation highlights the hydrogen atom transfer (HAT) process between the excited‐state POM and benzaldehyde for acyl radical formation. This highly reactive acyl radical is readily trapped by the Michael acceptor, thereby enabling subsequent C−H functionalization. Highly efficient gram‐scale flow operation underlines the industrial applicability of this transformative strategy.
Bifunctional Ligands: Evaluating the Role of Acidic Protons in the Secondary Coordination Sphere
Authors: Jain Anant Kumar , Malakar Santanu , Cannon Austin T. , Gonzalez Sophia Miranda M. , Keller Taylor M. , Carroll Patrick J. , Gau Michael R. , Kuo Jonathan L. , Goldberg Karen I. 
Published: July 2024

AbstractTo evaluate bifunctional ligand reactivity involving NH acidic sites in the secondary coordination sphere, complexes where the proton has been substituted with a methyl group (NMe) are often investigated. An alternative strategy involves substitution of the NH group for an O. This contribution considers and compares the merits of these approaches; the synthesis and characterization of cationic square‐planar Rh carbonyl complexes bearing diprotic bispyrazole pyridine ligand L1, and the bis‐methylated pyrazole pyridine ligand L1Me are described. The syntheses and characterization of the novel monoprotic pyrazole isoxazole pyridine ligand L2 and aprotic bisisoxazole pyridine ligand L3, and their corresponding Rh carbonyl complexes are also described. Comparison of the CO stretching frequencies of the four Rh complexes suggest that substitutions of NH with NMe, as well as with O, lead to significant electronic differences. These electronic differences result in different reactivities with respect to ligand addition/substitution of the Rh carbonyl complexes. Overall, the data suggest that electronic differences arising due to the NH substitutions can be significant and should be considered when the NH group is substituted in investigations of the participation of the NH proton in a reaction.
Air processed, high open‐circuit voltage indoor organic photovoltaic cells based on side chain modified N‐annulated perylene diimides
Authors: Nazari Maryam , Cieplechowicz Edward , Welch Gregory C. 
Published: July 2024

AbstractTo achieve high‐performance indoor organic photovoltaics (OPVs), it is important to match the photoactive layer optical absorption with the light‐source emission. This can be accomplished by developing organic photoactive materials that can efficiently absorb visible light and thus minimize energy losses. While indoor OPVs have achieved efficiencies above 33% under low light intensities, the power output is limited by low open circuit voltages (VOC), often well below 1 V. In this study, we present a series of visible‐light absorbing (energy gap >1.90 eV) non‐fullerene acceptors (NFAs) based on perylene diimide dimers, which have been systematically modified with side chains of varying polarity and steric bulk (trimethyl benzyl, ethyl adamantane, trialkoxyl phenyl, and oligo ethylene glycol). Our results show that the incorporation of sterically bulky side chains such as ethyl adamantane and trimethyl benzyl, blended with the common widegap polymer PTQ10, provides photoactive layers with absorption greater than 2.0 eV, and consequently, VOCs higher than 1.2 V are achieved under AM 1.5 G illumination. Importantly, we found that the NFA with ethyl adamantane based side chains (tPDI2N‐ethyl adamantane, compound 4) exhibited the best performance, with minimized energy loss. As a result, devices using PTQ10:tPDI2N‐ethyl adamantane photoactive layers demonstrated excellent indoor efficiencies of over 16% and 18 μW cm−2 power output under a 2700 K LED lamp at 300 lux, and showed better repeatability compared to other systems. The PTQ10:tPDI2N‐ethyl adamantane based devices maintained a high VOC (>1.0 V) across a wide range of indoor lighting conditions, including 2700 K and 6500 K LED lamps. Overall, this work provides a sidechain engineering method to create NFAs for efficient indoor OPV devices.
Intensification of fructose dehydration into 5‐HMF and subsequent oxidation to 2,5‐FDCA using ultrasound
Authors: Aranha Danwyn J. , Kininge Madhuri M. , Gogate Parag R. 
Published: July 2024

AbstractUltrasound‐assisted dehydration of fructose into 5‐hydroxymethylfurfural (5‐HMF) and subsequent oxidation to furandicarboxylic acid (2, 5‐FDCA) is studied in the current work with the main objective being to elucidate the effectiveness of ultrasound for intensified synthesis. The effect of reaction parameters like ultrasound power, duty cycle, reaction time, reaction temperature, solid to solvent ratio, and fructose concentration on the dehydration of fructose into 5‐HMF has been studied. Optimized conditions established were ultrasonic power of 140 W, duty cycle of 60%, reaction time of 60 min, temperature of 100°C, and fructose:dimethylsulfoxide (DMSO) ratio of 3:100 (g/mL), which resulted in the highest 5‐HMF yield of 96% and fructose conversion of 100%. The conventional method carried out at optimized conditions resulted in only 13.5% as 5‐HMF yield. The obtained 5‐HMF was further oxidized to FDCA using Pd/C as the catalyst, H2O/DMSO as solvent, and K2CO3 as a base also using ultrasonic irradiation at 140 W power and 22 kHz frequency in the presence and absence of O2 as oxidant. 100% conversion of 5‐ HMF was obtained in 30 min and 4 h using ultrasound in the presence of O2 and in absence of O2, respectively. 75% conversion of 5‐HMF was observed using the conventional method in 5 h in the presence of O2. Overall, the intensification benefits of using ultrasound at both steps of synthesis has been successfully elucidated.
Application of uncertainty quantification techniques in the framework of process safety studies: Advanced dispersion simulations
Authors: Bellegoni Marco , Marroni Giulia , Mariotti Alessandro , Salvetti Maria Vittoria , Landucci Gabriele , Galletti Chiara 
Published: July 2024

AbstractIn the framework of process safety studies, consequence assessment of accidental scenarios is a crucial step affecting the eventual risk profile associated with the facilities under analysis. Conventional models used for consequence assessment are based on integral models, and may not be adequate to cope with the dynamic evolution of accidental scenarios and their three‐dimensional features. On the other hand, consequence assessment models based on computational fluid dynamics (CFD) approaches are promising to cope with complex scenarios and environments, but setting the simulation introduces relevant uncertainties associated with both the input data, assumptions, and with the modelling of physical effects involved. In the present study, uncertainty quantification (UQ) techniques are applied to support advanced safety studies based on CFD simulations of hazardous gas dispersion. Firstly, the accidental scenarios are characterized by defining release scenarios and conditions and quantifying source terms using integral models. At the same time, input meteorological data are gathered. This enables the development of high‐fidelity CFD simulations of gas dispersion based on different input sets and eventually the implementation of UQ techniques. The generalized polynomial chaos (gPC) expansion is employed to obtain hazardous gas concentration based on the variation of wind direction and speed. The present method is applied for the analysis of a real plant featuring a complex layout. The results show the advantages of the present approach by quantifying the influence of meteorological conditions and providing indications for supporting the development of protection systems and emergency measures.