Double Function Research Articles

Synthesis and Photophysical Properties of 4'-5' Disubstituted CinNapht Dyes Accessible through Double SNAr Late-Stage Functionalization.

This article describes the synthesis of a difluorinated CinNapht derivative in the 4' and 5' positions allowing the easy access to two new families of fluorophores by late-stage functionalization using SNAr. The first one comprises derivatives incorporating hindered aromatic amines in the 4' and 5' positions, which show redemission in apolar solvents. The second one is obtained through the use of dinucleophiles. Among them, Tetrahydroquinoxaline (THQ) and tetrahydrobenzodiazepine (THB) compounds show strongly redshifted emission. The photophysical properties of all the fluorophores in these two families are studied and rationalized by DFT and TDDFT calculations. The most promising compounds have been used to image living cells by confocal microscopy.

N‐Oxyl Radicals in Oxidative C−O Coupling: Free‐Radical Hydrogen Substitution and Addition to C=C Bonds

AbstractN‐oxyl radicals occupy an important place in free‐radical oxidative CH‐functionalization being one of the most efficient redox‐organocatalysts for hydrogen atom abstraction (HAT). Their applications include aerobic radical chain autoxidation, CH‐functionalization with the formation of carbon‐carbon and carbon‐heteroatom bonds. The persistent nature of N‐oxyl radicals combined with their high reactivity in HAT results in their unique dual chemistry: the same radical can both propagate radical chain reaction (at low N‐oxyl concentrations) and effectively “terminate” carbon‐centered radicals (at higher N‐oxyl concentrations). The latter case opens a new synthetic application area of N‐oxyl radicals, in which they act as both hydrogen abstracting species and O‐reagents for cross‐coupling with carbon‐centered radicals thus produced. Apart from the C−H bond cleavage, reactive N‐oxyl radicals have been extensively used recently in C=C double bond functionalization via radical addition reactions. In this review, both free‐radical CH‐functionalization reactions with the introduction of N‐oxyl fragments and alkene difunctionalizations by N‐oxyls are covered with emphasis on the relationship between reaction conditions and selectivity.

Atomic H over crystal surface: effective potential dependence on sample properties

Abstract We considered the behavior of the lowest electronic level of atomic H in a semi-infinite space bounded by a flat surface. 
We impose a third kind boundary condition on the electronic wave functions, where the boundary condition parameter models the adsorbent properties of the surface.
For the crystal surface, the double periodic function as the boundary parameter seems reasonable; therefore, this case is considered.
It is shown that there are two modes of atom adsorption on the sample surface depending on the parameters of the boundary condition. 
In the first case the effective atomic potential, considered as a function of the distance between H and the boundary plane, exhibits a well pronounced minimum at some finite distance and a relatively small effective range of interaction distances between the atoms and samples.
The second case occurs under the condition of a large positive affinity of the atomic electron to the sample boundary and low initial H-concentration inside the sample. 
In such a situation, the minimum of the effective potential is close to the sample surface, and a significant amount of energy can be emitted throughout the adsorption process.

Revisiting the Baddeley Reaction: Access to Functionalized Decalins by Charge‐Promoted Alkane Functionalization

C–H functionalization of purely aliphatic substrates is a challenging endeavor, as the absence of directing groups generally thwarts attempts at regiocontrol. This is particularly true for difunctionalization reactions, where the control of relative stereochemistry poses an additional obstacle. The Baddeley reaction of decalins, despite suffering from strong limitations with regard to yield and generality, stands as one of only few known transformations capable of regio‐ and stereocontrol in aliphatic C–H functionalization. Herein, we report a regio‐ and diastereoselective method for the double functionalization of decalins enabling access to a novel, unreported regioisomer in synthetically useful yields. This method was also successfully applied to a range of other alkane substrates, enabling a straightforward synthesis of keto alcohols from the simplest alkane building blocks.

Revisiting the Baddeley Reaction: Access to Functionalized Decalins by Charge-Promoted Alkane Functionalization.

C-H functionalization of purely aliphatic substrates is a challenging endeavor, as the absence of directing groups generally thwarts attempts at regiocontrol. This is particularly true for difunctionalization reactions, where the control of relative stereochemistry poses an additional obstacle. The Baddeley reaction of decalins, despite suffering from strong limitations with regard to yield and generality, stands as one of only few known transformations capable of regio- and stereocontrol in aliphatic C-H functionalization. Herein, we report a regio- and diastereoselective method for the double functionalization of decalins enabling access to a novel, unreported regioisomer in synthetically useful yields. This method was also successfully applied to a range of other alkane substrates, enabling a straightforward synthesis of keto alcohols from the simplest alkane building blocks.

Novel foam‐draining and anti‐polymerization integrated agent for gas well application

AbstractIn this article, surfactants such as cetyl trimethyl ammonium chloride (CTAC) and coconut oil amide propyl betaine (CAB) were compounded (TCJ) and used as a double function with foam drainage and hydrate anti‐polymerization. According to the result it was found that 0.05% of CTAC and 0.7% of CAB exhibited both excellent foam property and hydrate anti‐polymerization property. For further clarifying the stability characteristic of foam, the foam half‐life, drainage process, microcosmic liquid film structure, and stability mechanism were investigated in this article. The high initial foam volume of 415 mL with relatively long half‐life time of 5.5 min under high‐speed agitation at 50°C after 25 min indicated a good temperature resistance. The excellent foam properties still remained even amount of methanol and NaCl was added, which indicated its well stability and salt resistance. Furthermore, it was found that TCJ exhibited high liquid carrying rate of 62.5% at 65°C and good compatibility with poly vinyl pyrrolidone (PVP), which played great potential to the application in oil field. By the results of DSC curves, it can be found that the phase transformation point of hydrate decreases after addition of TCJ, which indicates the inhibition to the formation of hydrate as thermodynamic inhibitors.

Development of craquelure patterns in paintings on canvas

Canvas paintings are layered structures composed of canvas support sized with animal glue, a preparatory layer of the ground, and paint and varnish layers on the top. Preventing or limiting humidity-induced stresses in these structures requires an understanding of the relevant processes and risks. A three-dimensional model of a canvas painting was used to analyse stresses and crack development in the two-layer structure comprised of a glue-sized canvas on a wooden stretcher with a layer of stiff chalk-glue ground representing a pictorial layer in historic canvas paintings. The model was subjected to a large relative humidity fall which induced shrinkage of the glue-sized canvas. The modelling revealed that when a stretcher with flexible wooden bars is considered, high tensile stresses arise in the ground layer at the corners of the painting, and cracks are formed in these areas in the direction perpendicular to the painting’s diagonal. Ratios of critical distances between cracks to the ground layer thickness for which stresses in the midpoints between the cracks dropped to below the level inducing fracture in the material were estimated for various magnitudes of the relative humidity drop and thicknesses of the ground layer. Increasing ground layer thickness limits the hygric response of the sized canvas and makes the paintings less vulnerable to humidity variations. The ratio of stress along the diagonal calculated for painting with one crack to the solution without cracks was described by the double Lorentz function. A simple procedure of calculating stress variations along the diagonal—using the function—on a sequential addition of cracks was developed. Cracks in central parts of canvas painting were found to be induced by permanent cumulative drying shrinkage of the oil-based paints and grounds due to the evolution of the molecular composition of the oil binder. The outcome of the modelling indicated that the risk of cracking of the pictorial layers in canvas paintings due to drops in ambient relative humidity was small.

Raman Thermometry for Temperature Assessment of Inorganic Transformations During Microwave Heating

ABSTRACTMicrowave heating is an intriguing method for the synthesis of inorganic solids offering a variety of advantages over conventional furnace heating, such as fast heating and cooling rates as well as volumetric and selective heating of precursors. However, there are many open questions regarding this “black‐box” process, and insights into the effect of microwave radiation on different types of solids are generally missing. In situ Raman spectroscopy is a powerful technique to unravel chemical transformations and identify intermediate species during microwave solid‐state syntheses. A major challenge is the temperature measurement under microwave conditions because (metallic) thermocouples cannot be used and optical pyrometry has significant drawbacks. In contrast, Raman thermometry is a viable method that relies on the temperature‐induced shift of Raman signals. Here, we use this method to estimate the temperature during microwave heating of a model system (titania) that undergoes a phase transition at temperatures >800°C. The estimation is derived from a flexible double exponential calibration function applied to Raman spectroscopic peak shifts in the temperature‐resolved furnace heating data, which was found to describe two titania modes (one anatase and one rutile) extremely well. Based on a detailed error and uncertainty analysis, we suggest options to further optimize Raman thermometry for use in high‐temperature microwave heating conditions.

Probing double-distribution-function models in discrete-velocity Boltzmann methods for highly compressible flows: Particles-on-demand realization

The double distribution function approach is an efficient route toward an extension of kinetic solvers to compressible flows. With a number of realizations available, an overview and comparative study in the context of high-speed compressible flows is presented. We discuss the different variants of the energy partition, analyses of hydrodynamic limits, and a numerical study of accuracy and performance with the particles on demand realization. Out of three considered energy partition strategies, it is shown that the nontranslational energy split requires a higher-order quadrature for proper recovery of the Navier-Stokes-Fourier equations. The internal energy split, on the other hand, while recovering the correct hydrodynamic limit with fourth-order quadrature, comes with a nonlocal—both in space and time—source term that contributes to higher computational cost and memory overhead. Based on our analysis, the total energy split demonstrates the optimal overall performance. Published by the American Physical Society 2024

Linking Metastatic Potential and Viscoelastic Properties of Breast Cancer Spheroids via Dynamic Compression and Relaxation in Microfluidics.

The growth and invasion of solid tumors are associated with changes in their viscoelastic properties, influenced by both internal cellular factors and physical forces in the tumor microenvironment. Due to the lack of a comprehensive investigation of tumor tissue viscoelasticity, the relationship between such physical properties and cancer malignancy remains poorly understood. Here, the viscoelastic properties of breast cancer spheroids, 3D (in vitro) tumor models, are studied in relation to their metastatic potentials by imposing controlled, dynamic compression within a microfluidic constriction, and subsequently monitoring the relaxation of the imposed deformation. By adopting a modified Maxwell model to extract viscoelastic properties from the compression data, the benign (MCF-10A) spheroids are found to have higher bulk elastic modulus and viscosity compared to malignant spheroids (MCF-7 and MDA-MB-231). The relaxation is characterized by two timescales, captured by a double exponential fitting function, which reveals a similar fast rebound for MCF-7 and MCF-10A. Both the malignant spheroids exhibit similar long-term relaxation and display residual deformation. However, they differ significantly in morphology, particularly in intercellular movements. These differences between malignant spheroids are demonstrated to be linked to their cytoskeletal organization, by microscopic imaging of F-actin within the spheroids, together with cell-cell adhesion strength.

Rejuvenation of human mesenchymal stem cells using a nonintegrative and conditionally removable Sendai virus vector

Human mesenchymal stem cells (hMSCs) with extended lifespan and differentiation potential that can recapitulate in vivo characteristics could significantly contribute to basic research, drug development, and cell therapy. Specifically, they could ensure a stable supply of specific cellular resources, and possibly extracellular vesicles. Here, we established a technology for extending the lifespan while maintaining differentiation potential, termed “rejuvenation,” of hMSCs (rej-hMSCs) using nonintegrative and conditionally removable temperature-sensitive Sendai virus (SeV) vectors. Various immortalizing factors (i.e., Bmi-1, hTERT, SV40T, and/or HPV E6/E7) were first introduced by the SeV vector into the cells. A combination of three SeVs with Bmi-1, hTERT, or SV40T conferred markedly improved cell proliferation and cloning ability while maintaining differentiation potential and a normal karyotype. An extended lifespan was also demonstrated in other cell types. The rejuvenation of long-passaged or aged hMSCs was also confirmed. SeV vectors were rapidly removed as a function of cell doubling by increasing the temperature from 35 °C to 37 °C or higher, while proliferative ability was maintained. Following FACS sorting, the complete removal of SeV vectors was confirmed by qPCR analyses. Therefore, our cell rejuvenation technology could contribute to research and clinical applications by enabling the supply of modified cells without damaging host chromosomes.

An Efficient Numerical Algorithm for Abnormal Integrals with Arbitrary Order Double Bessel Functions of the First Type

Abstract The integrals of the first type of double Bessel functions have a wide range of applications in geological exploration, mechanical and electromagnetic responses, signal processing, scattering, and wetting. In this paper, we develop a linear transformation accelerated convergence algorithm (LTACA) that combines the large argument approximate expression of the Bessel function (LAAEBF) and the integral accumulation to provide an efficient numerical algorithm for abnormal integrals with arbitrary order double Bessel functions of the first type. The effectiveness and high efficiency of the algorithm are verified by numerical examples, and its high accuracy is demonstrated by comparison with the Gaver-Stehfest inverse Laplace transform method (GSILTM). This offers a reliable and efficient computational method for the study of signal processing and mechanical problems.

Spatio-Functional Nadaraya–Watson Estimator of the Expectile Shortfall Regression

The main aim of this paper is to consider a new risk metric that permits taking into account the spatial interactions of data. The considered risk metric explores the spatial tail-expectation of the data. Indeed, it is obtained by combining the ideas of expected shortfall regression with an expectile risk model. A spatio-functional Nadaraya–Watson estimator of the studied metric risk is constructed. The main asymptotic results of this work are the establishment of almost complete convergence under a mixed spatial structure. The claimed asymptotic result is obtained under standard assumptions covering the double functionality of the model as well as the data. The impact of the spatial interaction of the data in the proposed risk metric is evaluated using simulated data. A real experiment was conducted to measure the feasibility of the Spatio-Functional Expectile Shortfall Regression (SFESR) in practice.

Analysis of characteristics of rice tillering dynamics influenced by sowing dates based on DTM

To quantitatively analyze the regularity and characteristics of tillering dynamics of rice at different sowing dates. In this paper, the whole process of rice tillering was decomposed into two aspects: tiller occurrence and tiller extinction, and two Logistic functions were used to describe them respectively, so as to establish a dynamic tillering model in rice based on double Logistic function (Dynamic Tillering Model, DTM). Then, according to DTM, dynamic tillering indexes (DTIs) were defined and their calculation formulas were derived. Finally, the characteristics and laws of rice tillering dynamic response to sowing dates were analyzed using DTM and DTIs with the observed tillering data of three rice varieties, (Hui-Liangyou 898 (HLY898), Y-Liangyou 900 (YLY900) and Y-Liangyou 911 (YLY911)), in six sowing dates (March 15, March 20, March 25, March 30, April 5, April 10). The results show that: 1. The model fits well. The normalized RMSE (RMSEn) of the DTM fitted to the observed tillering data of different rice varieties sown at different times were all less than 10 %, and their mean values were less than 5 %. 2.The variation degree of DTIs under the influence of sowing dates had certain consistency among the three rice varieties. the inherent rate of tillering (Rit), the maximum tillering rate (Rmt), the maximum tillers extinction rate (Rme) and the duration of tillering (Dt) varied greatly, while the total number of grow tillers (Ng), the peak time of tillering (Tpt), the peak time of tillers extinction (Tpe) and the end time of tillering (Tet) had smaller variation. 3. The eight DTIs, the inherent rate of tillering (Rit), the duration of tillering (Dt), the maximum tillering rate (Rmt), the number of retained tillers (Nr), the peak time of tillering (Tpt), the end time of tillering (Tet), the start time of tillers extinction (Tse) and duration of tillers extinction (De), had a consistent linear response to the sowing dates among the three rice varieties. 4. Under different sowing dates, the dynamic characteristics of tillering of YLY900 and YLY911 were relatively close, while HLY898 had great differences from YLY900 and YLY911. In this paper, the evolution process of the number of tillers of rice was accurately described by the DTM, and the regularity and characteristics of tillering dynamics of rice were deeply revealed using the DTIs, with agronomic experiment of three varieties with six sowing dates. Therefore, it has important theoretical value to deeply understand the law of the tillering dynamic of rice affected by sowing dates and has important practical significance for guiding accurate planting and fine management of rice production from the perspective of grasping tillering dynamics.

‘Have you insured yourself in any way?’ Salespersons’ mapping questions and their follow-ups in insurance sales negotiations

This study examines how insurance salespeople employ a mapping question to promote life insurance as an additional service to their customers. The mapping question serves a double function, asking about the customer’s situation and creating a context in which transaction-related negotiation is projected to occur. Applying conversation analysis to study video-recorded insurance meetings in Finland, we explore how the mapping question is designed according to the customer’s estimated fit with the target group criteria and their assumed level of understanding of life insurance. We also discuss the trajectories of the negotiation after the customer’s response that expresses interest, conveys hesitation, or rejects the offer. It was found that only a customer’s justified blocking response forestalls further life insurance promotion. The study contributes to the research on questions as agenda-driving actions in institutional interaction and to the literature on question-answer sequences in service encounters.

Assessing the phenological state of evergreen conifers using hyperspectral imaging time series

Phenology is a reliable indicator of vegetation condition and ecological changes in the environment. Plant Spectral Phenology (PSP) offers the potential for the development of automated, rapid, and wide-area vegetation monitoring systems. The spectral characteristics of plants (vegetation) are employed as metrics of PSP, which can be sensed both proximally and remotely. A key objective is to undertake a comparative analysis of the results of PSP versus those of phenology based on visual observations. The resolution of this issue is of paramount importance for the coordination of phenological studies at diverse levels (ground, surface, and remote), thus ensuring the continuity of phenological studies conducted prior to the advent of PSP. This issue is particularly pronounced in the case of evergreen conifers. The present study focuses on four evergreen conifers: Thuja occidentalis, Platycladus orientalis, Pinus sylvestris and P. nigra subsp. pallasiana. Hyperspectral imaging was performed under laboratory conditions using a Cubert UHD-185 hyperspectral camera. Concomitantly, phenological observations were conducted. The spectral time series yielded 79 chlorophyll-sensitive and carotenoid-sensitive Vegetation Indices (VIs), which were then used to construct double logistic functions. A significant proportion of the VIs exhibited a high degree of correctness with regard to the aforementioned functions, as indicated by the value of R2 exceeding 0.7. The values of the principal stages of seasonal development of evergreen conifers, namely the Start of Season (SOS), End of Season (EOS), Position of Peak value (POP) and Length of Season (LOS), were calculated using double logistic functions. These stages were matched to the phenological phases of development of the experimental plants. The values of SOS, EOS, POP and LOS varied significantly depending on the VIs used as a metric as well as the evergreen conifers. The lowest variability by metrics is observed in SOS, while the maximum is observed in EOS and POP. The results obtained may be of importance for the choice of criterion for the comparison of PSP with phenology based on visual observations and the most suitable VIs for these purposes.

Improved Quantum Rebound Attacks on Double Block Length Hashing with Round-Reduced AES-256 and ARIA-256

At EUROCRYPT 2020, Hosoyamada and Sasaki proposed the first dedicated quantum collision attacks on hash functions. Their proposal presented a quantum adaptation of the rebound attack and revealed that differential trails, which have too low probability for use in classical settings, might be exploitable in quantum settings. After their work, subsequent research has actively delved into analyzing the security of hash functions in the quantum setting.In this paper, we revisit the quantum rebound attacks on the double block hash function Hirose instantiated with 10-round AES-256 (HCF-AES-256) and 7-round ARIA-256 (HCF-ARIA-256) proposed by Chauhan et al. and Baek et al., respectively. Initially, we identify the flaws in their work and reevaluate the complexity of the attacks. We reveal that the flaws stem from not considering the issue that the S-box differential equation has one solution on average. Earlier research addressed this problem by adding auxiliary bits to the search space. If this method is used to correct the flaws, the resulting time complexities are 217.36 and 220.94 times higher than their proposals. Consequently, in some settings, their attacks become less efficient than generic attacks.Subsequently, we propose improved quantum rebound attacks using nested quantum amplitude amplification and quantum state preparation. Our improved attack efficiently pre-filters the search space, leading to a reduction in overall time complexity. We first classically reduce the search space and employ quantum state preparation to generate a superposition state over the pre-filtered search space. We then use nested quantum amplitude amplification to further reduce the search space quantumly. As a result, we achieve a reduction in the time complexity of the quantum rebound attacks on HCF-AES-256 and HCF-ARIA-256 by factors of 211.2 and 219.5, respectively, making the attacks more efficient than generic attacks again.

Approximation by Double Periodic Functions in the Classes $$C_{A}^{{r*}}$$

Approximation by Double Periodic Functions in the Classes $$C_{A}^{{r*}}$$

Constraining the Earth-mass Primordial Black Hole Mergers Model of the Non-repeating FRBs Using the First CHIME/FRB Catalog

In this paper, we upgrade the constraints for the Earth-mass primordial black hole mergers model based on the first Canadian Hydrogen Intensity Mapping Experiment (CHIME)/fast radio burst (FRB) catalog. Assuming the null hypothesis that the observed non-repeating FRBs originate from Earth-mass primordial black hole mergers, we find that how the charges were distributed in the primordial black hole population is well described by a double power-law function with typical charge value of qc/10−5=1.60−0.28+0.28 , where the power-law index α1=2.33−0.18+0.15 for q < q c and α2=4.56−0.26+0.30 for q ≥ q c. Here, q represents the charge of the black hole in units of GM , where M is the mass of the black hole. Furthermore, we infer the local event rate of the bursts is 8.8−2.1+5.7×104Gpc−3yr−1 , which indicates that an abundance of the primordial black hole population f ≳ 10−4 is needed to account for the observed FRBs by CHIME. The results of this paper lay the basis for further research on the electromagnetic radiation background generated by the merger of primordial black hole mergers.

Extreme-value modelling of the brightest galaxies at z ≳ 9

Abstract Data from the James Webb Space Telescope have revealed an intriguing population of bright galaxies at high redshifts. In this work, we use extreme-value statistics to calculate the distribution (in UV magnitude) of the brightest galaxies in the redshift range 9 ≲ z ≲ 16. We combine the Generalised Extreme Value (GEV) approach with modelling of the galaxy luminosity function. We obtain predictions of the brightest galaxies for a suite of luminosity functions, including the Schechter and double power law functions, as well as a model parametrised by the stellar formation efficiency f*. We find that the JWST data is broadly consistent with f* of $5~{{\ \rm per\ cent}}-10~{{\ \rm per\ cent}}$, and that the brightest galaxy at z ∼ 16 will have $M_{\rm UV}\approx -23.5^{0.8}_{0.4}$. If f* is dependent on halo mass, we predict $M_{\rm UV}\approx -22.5^{0.5}_{1.5}$ for such an object. We show that extreme-value statistics not only predicts the magnitude of the brightest galaxies at high redshifts, but may also be able to distinguish between models of star formation in high-redshift galaxies.