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Dual-state emission (DSE), the emission of organic molecules in solution and solid state, has recently drawn interest for advanced performance materials. Here, we report conjugated compounds 1and 2with good photoluminescence (PL) in solution (ΦPL = 0.53 and ΦPL = 0.43) and exceptional emission in the solid state (ΦPL = 0.92 and ΦPL = 0.84). These donor-π-acceptor-π-donor (D-π-A-π-D) compounds with rotary components adopt different highly emissive states, according to our PL measurements. Time-dependent density functional theory (TD-DFT) calculations indicate that the PL changes are facilitated by polarizable moieties, with the possibility of trapping in the higher energy S2state and anti-Kasha emission in viscous solutions. Complementarily, the flexibility and symmetry (or the lack thereof) of each molecule play a critical role in producing strongly fluorescent twisted structures in the solid state.

Addressing the multiple challenges associated with sulfur chemistry is imperative to unlock the full theoretical capacity of sulfur (1675 mAh·g−1) in Lithium-Sulfur Batteries. In pursuit of this objective, two linear copolymers were meticulously designed to serve as binders, exhibiting various capabilities such as polysulfides trapping, improved ionic conductivity, and adaptation to extreme volume changes. The synthesis of these polymers viaRAFT polymerization ensured uniform molecular weight and enabled control over the chemical structure's organization—whether random or block copolymers. While the inclusion of distinct moieties, namely sodium polystyrene sulfonate and polyacrylates with pendant oligoethers groups, played a pivotal role in addressing the challenges associated with sulfur chemistry, the chemical structure emerged as the key factor significantly influencing the physicochemical properties. Insights gathered from tensile tests, polysulfide trapping assessments, swelling rates, electrochemical characterizations, and ab initiosimulations underscored the profound impact of the chemical structure. Triblock copolymer demonstrated superior outcomes, including enhanced capacity retention (500 mAh·g−1at 1C and ~ 800 mAh·g−1at C/10), lower cell polarization (118 mV), and very high stable capacity at 100 cycles, compared to the random copolymer and overpassing traditional PVDF binders. This enhancement is attributed to the formation of predominant ionic conductive regions, which, owing to the specific chemical structure, remains unaffected by swelling upon interaction with the electrolyte.

Dual-organelle molecular localizers represent powerful new tools allowing the exploration of interorganelle physical contacts and subcellular chemical communication. Here, we describe new dynamic molecular probes to localize mitochondria and lipid droplets taking advantage of the differential proton gradients present in these organelles as well as the activity of mitochondrial esterase. We unveil their potential utility when organelle retention mechanisms and proton gradients are synchronized, an insight that has not been documented previously. Our discoveries indicate that dual-organelle probes serve as a valuable multiplexing assay during starvation-induced autophagy. The pioneering molecular mechanism they employ opens doors to avoid using labile esters such as acetoxymethyl derivatives which are not optimal in imaging microscopy assays.

Membrane tension pores determine organelle dynamics and functions, giving rise to physical observables during the cell death process. While fluorescent organelle-targeted probes for specific chemical analytes are increasingly available, subcellular dynamic processes involving not only chemical parameters but also physicochemical and physical parameters are uncommon. Here, we report a mitochondrial chemical probe, named RCN, rationally designed to monitor osmotic effects during transmembrane tension pore formation by using local mitochondrial polarity and a subcellular localization redistribution property of the probe. Utilizing fluorescence spectroscopy, high-resolution confocal imaging, and spectrally resolved confocal microscopy, we provide a new correlation between mitochondrial dynamics and bleb vesicle formation using osmotic pressure stimuli in the cell, where the mitochondrial local polarity was found to drastically increase. The RCNprovides a reliable protocol to assess transmembrane pore formation driven by osmotic pressure increments through local polarity variations and is a more robust physicochemical parameter allowing the health and decease status of the cell to be measured.

A multicomponent diversity-oriented synthesis of new highly emissive tetracyclic isoquinolines that target specific organelles is described. The title compounds were prepared via a three-step protocol starting with an Ugi four-component reaction, followed by either an intramolecular alkyne hydroarylation and subsequent alkene isomerization or through a Pomeranz–Fritsch-type cyclization with a final intramolecular Heck reaction. Subcellular localization studies of these compounds using green channel confocal microscopy revealed remarkable and distinctive distribution patterns in live cells, showing an unprecedented high selectivity and imaging contrast. The differentiated organelle visualization—including localizers for mitochondria, lysosomes, Golgi apparatus, endoplasmic reticulum, and plasma membrane—was achieved by varying the nature of the tetracyclic system and substituent pattern, changing the original four-component set in the starting Ugi reaction.

There is increasing interest in new processes to produce aromatics labeled as “natural”, and as a consequence, enzymatic processes, in some organic solvent or in solvent-free medium, have been developed. This paper offers a kinetic study of lipase-catalyzed transesterification for synthesizing 2-phenylethyl acetate in a batch reactor using Novozym 435 and hexane as solvent. The influence of five variables on conversion is studied. A pseudo-first-order kinetic model, derived as a simplification of bisubstrate ping-pong kinetics, is presented. The amount of catalyst was the variable most affecting kinetic and yield, while initial substrate concentration had little effect on the reaction kinetic. The yield increased gradually as the molar ratio increased and was more pronounced with vinyl acetate than 2-phenethyl alcohol. Michaelis constants of both substrates and maximum reaction rate, for the range of assayed experimental conditions of temperature, stirring speed, and enzyme concentration, were determined and compared with others in the literature. Finally, the proposed kinetic model was validated with high correlation coefficients.

A homologous series of dithiocarbamate ligands derived from N-substituted amino acids was reacted with different diorganotin dichlorides to give 18 diorganotin complexes. Spectroscopic and mass spectrometric analysis evidenced the formation of assemblies with six-coordinate tin atoms embedded in skewed-trapezoidal bipyramidal coordination environments of composition C2SnS2O2. Single-crystal X-ray diffraction analysis for three of the compounds revealed a one-dimensional polymeric structure for the complex with the ligand derived from 5-aminopentanoic acid, which through further intermolecular Sn···O interactions generated an overall two-dimensional coordination polymer containing 40-membered hexanuclear tin macrocycles. On the contrary, the ligands derived from 6-aminohexanoic and 8-aminooctanoic acid provided the expected 22- and 26-membered dinuclear macrocyclic structures. Density functional theory calculations for a representative series of macrocyclic complexes of composition [Me2SnLx]2with Lx= ¯S2CN(Me)-(CH2)x-COO¯ (x= 3–12) enabled a detailed analysis of the variations in the molecular conformation, shape, and cavity size of the macrocycles in dependence of the aliphatic spacer. Because of odd–even effects, the difunctional ligands can adopt either a curved or a twisted-pincer shape, while the SnSxO4-x(x= 0–4) moieties can act either as linear or angular tectons with varying connectivity angles.

Nonclassical protomeric tautomerism in Schiff bases have the advantage of controlling and differentiating specific interactions in the −CN– linkage since its interactions are not governed by keto–enol tautomerism. Here, we report about the optical properties of a Schiff base probe (P1). X-ray structure analysis evidenced the existence of an intramolecular hydrogen bond which is responsible of a photochromic-fluorescent behavior. The properties of P1were investigated by UV–vis and fluorescence spectroscopy in solution and solid state. A positive solvatochromism resulting from specific interactions taking place in P1was studied by three different solvent scales, namely Lippert–Mataga, Kamlet–Taft, and Catalán, finding consistent results. Moreover, a strong acidochromic behavior was detected and the pKaand pKa* values were determined, finding a photobasic character. Further, an ionochromic behavior was stablished. P1exhibits a λ-ratiometric fluorescence response toward Sn(IV) giving a luminescence color change from blue to green, displaying also a chromogenic response. Finally, theoretical calculations were conducted to analyze the probe mechanism in terms of natural transition orbitals (NTOs) and spatial extent of charge transfer excitations. The present contribution focused on the factors determining the ability of a single Schiff base probe to present photo-, solvato-, acido-, and ionochromism.

Abstract: Potatoes play the role of a vegetable or a complementary dish in the Mexican diet. They are mainly consumed fresh. Dried vegetables of the particular interest in preparation of dry mixtures are used for soups. The rapid expansion of the fast food industry could result in an increase in the use of dehydrated potatoes, as a component for vegetable mixture and soups. However, Pre-drying treatments such as addition of antioxidants are needed for vegetable drying as the potato in order to avoid changes of color. In this work, the influence of different pre-treatments and drying conditions on physical characteristics (moisture content, water activity and color difference) of thinly sliced potato during drying by fluidized bed was investigated. The thinly sliced samples of fresh potato were dipped into solutions containing citric acid (0, 0.5 and 1 % w/w) before drying. Potato sample were dehydrated at air temperatures of 40, 50 and 60 °C. The second degree polynomial model was used to describe the response variables. The analysis of variance (ANOVA) for all coded models indicated that the models were statistically significant (p ≤ 0.05). The temperature and citric acid increment increases color difference, and decreases the moisture content and water activity of the dehydrated samples of potato. Color closest to the original color of fresh potato was obtained in some treatments. In general, it was observed that the drying of thinly sliced potato was influenced by pretreatment.

This article presents information on the insurance sector in Latin America. The region's biggest insurance markets are finally beginning to show their true potential. Against a background of economic growth and stable currencies, the leading insurers in the region are taking advantage of increasing demand for cover. Growth economies, single-digit inflation rates, low interest rate environments and stable currencies are driving the recovery of the insurance industry in Latin American countries. Direct premiums show sustained annual growth rates above 10% in average, while adjusted capitalization levels have strengthened more than 35% in the last year. A more stable environment means that life insurance business is showing the most dynamic performance with average growth rates of approximately 15%.

The reaction between trans‐PcSiCl2(1) and the potassium salts of six fatty acids (2 a–2 f) led to the trans‐PcSi[OOC(CH2)nCH3]2compounds (3 a–3 f), which were characterised by elemental analysis, IR, UV/Vis and 1H, 13C, and 29Si NMR spectroscopy. From a detailed study of the NMR spectra, the strong anisotropic currents of the Pc macrocycle were found to have an effect on up to the sixth methylenic group. As expected, the length of the hydrocarbon tail does not affect the chemical shift of the 29Si nucleus of any of the compounds, appearing at around −222.6. The structures of PcSi[OOC(CH2)nCH3]2, where n=7, 10, 12, 13 and 20, were determined by X‐ray crystallography. All the compounds were found to be triclinic with a P$\bar 1$space group. In all cases the observed crystallographic pseudosymmetry is Ciand the asymmetric unit consists of half a molecule. The silicon atom is at the centre of a distorted octahedron and hence its coordination number is six. The carboxylate fragments are in a transconfiguration with respect to the Pc macrocycle. The supramolecular structures are discussed in detail herein. The correlation between the 1H NMR chemical shifts and the position of the corresponding carbon atoms in the hydrocarbon tail reveals that the dicarboxylate substituents exhibit a spacer‐like behaviour that enhances the solubility. A detailed study of the tail variable allowed us to evaluate the loss of radial shielding along the Pc2−ligand.

Thermal and microwave reactions between [PcSnIVCl2] (1) and the potassium salts of eight fatty acids (2 a–h) led to cis‐[(RCO2)2SnIVPc] compounds (3 a–h) in yields ranging from 54 to 90 %. Compounds 3 a–hwere fully characterized by elemental analysis, spectroscopy (IR, UV/Vis, multinuclear NMR), and seven X‐ray diffraction structures, whereby two different allotropes were observed in two cases. The two carboxylates in 3have a cisanisobidentate binding mode, octacoordination of the tin atoms with square‐antiprismatic geometry, and π‐electron‐rich nanocap shapes. On account of the latter characteristics, 3 a–hcompounds have anticorrosion properties. LPR and Tafel electrochemical methods were used to characterize the behavior of these derivatives in naturally aerated sour brine, which is a common environment in petroleum production and refinery operations. The measurement of the corrosion rate of carbon steel AISI 1018 in the presence of 3 a–h(500 ppm) gave efficiencies of 61–87 % for the inhibitor performance. Of the different derivatives examined, compounds 3 eand 3 hwere the most effective corrosion inhibitor prototypes.

Abstract.: The rheological behavior of a cetylpyridinium chloride 100 mmol l–1/sodium salicylate 60 mmol l–1 aqueous solution was studied in this work under homogeneous (cone and plate) and non-homogeneous flow conditions (vane-bob and capillary rheometers), respectively. Instabilities consistent with non-monotonic flow curves were observed in all cases and the solution exhibited similar behavior under the different flow conditions. Hysteresis and the sigmoidal flow curve suggested as characteristic of systems that show constitutive instabilities were observed when running cycles of increasing and decreasing stress or shear rate, respectively. This information, together with a detailed determination of steady states at shear stresses close to the onset of the instabilities, allowed one to show unequivocally that "top and bottom jumping" are the mechanisms to trigger the instabilities in this micellar system. It is shown in addition that there is not a true plateau region in between the "top and bottom jumping". Finally, the flow behavior beyond the upturn seemed to be unstable and was found accompanied by an apparent violation of the no-slip boundary condition.

We determined the enzymatic activity and crude subcellular distribution of four exopeptidases: Dipeptidylaminopeptidase IV (DAP-IV), Alanyl aminopeptidase (AAP), Prolyl aminopeptidase (PAP) and γ-Glutamyl transpeptidase (γGTP), and two endopeptidases: Postproline endopeptidase (PEP) and “Trypsin-like” peptidase (“T-L” P) in pars compacta (SNPC) and pars reticulata (SNPR) of substantia nigra, caudate-putamen (CAU) and cerebral cortex (CC) of the rat brain. We found: 1) DAP-IV activity is comparatively higher in SNPC and it is equally distributed in the postmitochondrial precipitate (PR) and supernatant (SN) fractions of SNPC, CAU and CC but higher in the SN from SNPR. 2) CC shows the highest activity of AAP and its activity is mainly located in the SN from all areas. 3) The activity of PAP is comparatively higher in SNPC and it is exclusively located in the SN from all areas. 4) γGTP activity is similar in all areas but its predominance is in the SN for SNPC and SNPR, and in the PR for CAU and CC. 5) CAU has higher PEP activity (higher in the PR) than CC (higher in the SN); no activity is detected in the substantia nigra. 6) The activity of a “Trypsin-like” peptidase is the highest in SNPC and SNPR; this activity have some predominance in the SN and higher predominance in the same fraction from CAU and CC.

An analysis of the flow of polymer solutions through capillaries by means of pressure profiles was performed in this work. The experiments were carried out with aqueous solutions of flexible and semirigid macromolecules, Polyox and Xanthan respectively. The influence of the macromolecules' conformation on the flow field development is reflected on the different magnitudes of the entry length, being of the order of 60 diameters for the solutions of rigid macromolecules, and of the order of 10 diameters for flexible ones. In addition, the calculated end effects were larger for the rigid macromolecules than for the flexible ones. From these results, it is found that an increase in the entrance length is observed when the pseudoplastic behavior of the polymer solutions is increased.

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Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.