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The 2-oxo-1,2-dihydroquinolin-8-yl 4-chlorobenzoate was synthesized in good yield using a triethylamine-mediated O-acylation reaction between 8-hydroxyquinolin-2(1H)-one and 4-chlorobenzoyl chloride in acetonitrile at room temperature. This methodology is notable for its clean reaction profile and straightforward procedure. The 2-oxoquinoline derivative was characterized using spectroscopic, spectrometric, and thermal analyses, enabling a comprehensive understanding of its molecular structure and thermal properties. [ABSTRACT FROM AUTHOR]

A correction notice has been issued for an article titled "Whey as an Alternative Nutrient Medium for Growth of Sporosarcina pasteurii and Its Effect on CaCO3 Polymorphism and Fly Ash Bioconsolidation." The correction addresses an error in Figure S1 and includes the replacement of the figure with the corrected version. The authors have also provided raw data for evaluation. The correction has been approved by the Academic Editor, and the original publication has been updated. The correction does not affect the scientific conclusions of the article. [Extracted from the article]

Corporate Social Responsibility -RSC- is a tool that can transform companies to establish policies aiming at the achievement of social development. With this stablished facts, this article intends to determine the level at which CSR is implemented in companies in Cuenca - Ecuador, analyzed from the perspective of those in charge of its management, collaborators and community; also noting that applying these kind of programs can improve their reputation. To establish the CSR level, 20 companies were investigated, taking a sample of 396 representatives of interest groups, divided into 198 collaborators and 198 members of the community, more than 20 spokespersons for the organizations. This study was developed on a quantitative approach; Information was collected on the activities carried out by the companies investigated and an analysis was made in order to verify the most practiced factors. After carrying out the surveys, it was observed that there is a coincidence between what the CSR management authorities and collaborators say, but discrepancies with the community actors' statements. [ABSTRACT FROM AUTHOR]

Quantum vacuum in large fields of the order of twice or greater than the critical Schwinger field 2Bc shows strong anisotropic properties: virtual photons as well as electrons and positrons tend to propagate in a parallel direction to the magnetic field. The photon self‐energy acquires an imaginary part, which suggests an instability. In order to overcome this anisotropic behavior, we propose an heuristic model based on fermion pairing of boson‐vacuum n in the form of virtual para‐positronium, a chiral noninvariant electron‐positron bound state leading to a ferromagnetic quantum phase transition of the vacuum for fields of order of twice the critical Schwinger field 2Bc. [ABSTRACT FROM AUTHOR]

Background Intracranial aneurysms are arterial anomalies affecting 2% to 3% of the general population in the world and these ruptures are associated with a high mortality. Some risk factors, such as age, gender, smoking, alcohol, hypertension and familial history are associated with the number of aneurysms and their size. In addition, inflammatory processes within the blood vessels of the brain can activate matrix metalloproteinase-9 (MMP-9), which degrades various components of the extracellular matrix, such as elastin. Thereby, this work has aimed at evaluating the relationship between plasma MMP-9 levels and the risk factors that are associated with intracranial aneurysm, as well as investigating the aneurysm statuses (ruptured and unruptured) and comparing them with the control volunteers. Methods Between August 2014 to June 2016, blood samples were collected from 282 patients (204 ruptured and 78 unruptured saccular intracranial aneurysms) and 286 control volunteers. The MMP-9 plasma levels were measured by ELISA. Statistical analyzes were performed with SPSS software when using parametric or nonparametric tests, after the normality tests. Results Higher levels of MMP-9 were found in the aneurysm groups as a whole and when they were stratified by rupture status, then compared with the control group (p < 0.0001). When stratifying them by diameter, those smaller than 7 mm presented high levels of MMP-9 (p < 0.0001), especially in the ruptured ones. As for risk factors, hypertension and smoking were the most important. However, hypertension was mostly associated with the ruptured aneurysms (p < 0.0001). Conclusions High levels of MMP-9 were found in smaller ruptured and unruptured intracranial aneurysms (<7 mm) with strongest statistical associations than other sizes, especially when associated with smoking and hypertension. [ABSTRACT FROM AUTHOR]

The synthesis of 5,5′-[oxybis(methylene)]bis-2-furfural (OBMF) from 5-hydroxymethylfurfural (5-HMF) was studied using bulk and alumina-supported Preyssler heteropolyacids (HPAs). The formation of OBMF was related to the amount of Brønsted acid sites, and the lowest yield of OBMF was obtained with supported HPAs. However, the Lewis acidity of the HPA supported on Al2O3 favored the formation of 2,5-dimethylfurane. The effects of solvent, catalyst loading, temperature, and reaction time on the selectivity to OBMF from 5-HMF were studied to optimize OBMF production using bulk Preyssler HPAs; a yield of 84 % to OBMF was obtained at 5 h and 343 K. These results demonstrate that bulk Preyssler HPA is a good candidate for OBMF synthesis under mild reaction conditions. [ABSTRACT FROM AUTHOR]

El articulo discute sobre la las ciencias básicas para el desarrollo ostensible con el enfoque de la física para la cuarta revolución industrial. El articulo también se centra en la el conocimiento sobre los principios fundamentales como la Física, la Matemática, la Química, el role de Big data en la lucha de la pandemia covid-19 y la contribución de física y tecnología digitales en en el proceso de producción industrial.

Background: Microbial production of nitrogen containing compounds requires a high uptake flux and assimilation of the N-source (commonly ammonium), which is generally coupled with ATP consumption and negatively influences the product yield. In the industrial workhorse Saccharomyces cerevisiae, ammonium (NH4+) uptake is facilitated by ammonium permeases (Mep1, Mep2 and Mep3), which transport the NH4+ ion, resulting in ATP expenditure to maintain the intracellular charge balance and pH by proton export using the plasma membranebound H+-ATPase. Results: To decrease the ATP costs for nitrogen assimilation, the Mep genes were removed, resulting in a strain unable to uptake the NH4+ ion. Subsequent analysis revealed that growth of this Δmep strain was dependent on the extracellular NH3 concentrations. Metabolomic analysis revealed a significantly higher intracellular NHX concentration (3.3-fold) in the Δmep strain than in the reference strain. Further proteomic analysis revealed significant up-regulation of vacuolar proteases and genes involved in various stress responses. Conclusions: Our results suggest that the uncharged species, NH3, is able to diffuse into the cell. The measured intracellular/extracellular NHX ratios under aerobic nitrogen-limiting conditions were consistent with this hypothesis when NHx compartmentalization was considered. On the other hand, proteomic analysis indicated a more pronounced N-starvation stress response in the Δmep strain than in the reference strain, which suggests that the lower biomass yield of the Δmep strain was related to higher turnover rates of biomass components. [ABSTRACT FROM AUTHOR]

In this paper, the calibration approach is revisited in order to allow new calibration weights that are subject to the restriction of multiple calibration equations on a vector of ratios, means and proportions. The classical approach is extended in such a way that the calibration equations are not based on a vector of totals, but on a vector of other nonlinear parameters. We stated some properties of the resulting estimators and carry out some empirical simulations in order to asses the performance of this approach. We found that this methodology is suitable for some practical situations like vote intention estimation, estimation of labor force, and retrospective stud- ies. The methodology is applied in the context of the Presidential elections held in Colombia in 2014 for which we estimated the vote intention in the second round using information from an election poll, taking the results from the first round as auxiliary information [ABSTRACT FROM AUTHOR]

Acetic acid decomposition for hydrogen production was investigated on Pd/SiO 2 , Pd/Nb 2 O 5 , Pd/La 2 O 3 and Pd/Fe 2 O 3 catalysts. The conversion of acetic acid started at 673 K and the products of the reaction were H 2 , CO, CH 4 , CO 2 , H 2 O and C 2 H 4 O. Pd/Fe 2 O 3 was the most active catalyst for conversion of acetic acid and showed high hydrogen selectivity and good catalytic stability, followed by Pd/Nb 2 O 5 and Pd/La 2 O 3 , whereas in the case of Pd/SiO 2 , there was not any H 2 formation. The Pd/Fe 2 O 3 catalysts presented reduced Pd–Fe and Pd 0 /Fe 2 O x sites, producing complete conversion of acetic acid and a higher level of hydrogen selectivity (73%). Additionally, acetic acid adsorption on Pd/Fe 2 O 3 , Pd/Nb 2 O 5 and Pd/La 2 O 3 catalysts yielded the formation of acetate surface species. However, in the case of Pd/SiO 2 , there was molecular adsorption of acetic acid. During the reaction, there was formation of an ordered and disordered carbon mixture on Pd/La 2 O 3 , Pd/Nb 2 O 5 and Pd/SiO 2 catalysts, while carbon of a more ordered nature was produced on Pd/Fe 2 O 3 . [ABSTRACT FROM AUTHOR]

The field of metabolic engineering has delivered new microbial cell factories and processes for the production of different compounds including biofuels, (di)carboxylic acids, alcohols, and amino acids. Most of these processes are aerobic, with few exceptions (e.g., alcoholic fermentation), and attention is focused on assembling a high-flux product pathway with a production limit usually set by the oxygen transfer rate. By contrast, anaerobic product synthesis offers significant benefits compared to aerobic systems: higher yields, less heat generation, reduced biomass production, and lower mechanical energy input, which can significantly reduce production costs. Using simple thermodynamic calculations, we demonstrate that many products can theoretically be produced under anaerobic conditions using several conventional and non-conventional substrates. [ABSTRACT FROM AUTHOR]

The effect of gold addition to iridium catalysts and the nature of active sites for citral hydrogenation were investigated over Ir–Au/TiO 2 catalysts. All samples (Au/TiO 2 , Ir/TiO 2 and Ir–Au/TiO 2 ) were prepared by deposition-precipitation with urea (DPU). Bimetallic catalysts were synthetized by co-deposition at different Ir/Au atomic ratios (3, 1, 0.3). The catalysts were characterized by ICP, BET, H 2 –TPR, H 2 -Chemisorption, TEM, DRIFTS and XPS techniques. A partial coverage of iridium sites by gold atoms takes place as the gold amount in the catalyst increases as shown by chemisorption and XPS measurements. The latter also evidenced a trend consistent with modification of the electronic environment of iridium due to interaction with gold atoms. Also, compared to Ir/TiO 2 , the amount of Ir δ+ species was higher in the bimetallic catalysts reaching a maximum in Ir–Au (1) sample. Characterization of the catalytic surface using DRIFTS of adsorbed CO evidenced a shift towards higher wavenumbers as a function of the gold content indicating, as the XPS results, a modification of the adsorption site. The catalytic activity for citral hydrogenation increased as a function of the gold content. The selectivity to unsaturated alcohol is related to the amount of Ir δ+ species which in turns depends on the catalyst composition. For the most active sample Ir–Au (1), a suitable Ir δ+ /Ir 0 ratio is already obtained when the catalyst is reduced at 573 K and does not vary with reduction temperature. [ABSTRACT FROM AUTHOR]

Fe3O4, Fe3O4-NH2, Fe3O4@SiO2 y Fe3O4@SiO2-NH2 as magnetic supports were studied for the urease immobilization. The solids were characterized by N2-physical adsorption at 77 K, magnetization curves and FTIR. Activity assays were evaluated by urea decomposition. The magnetic properties of solids allow an easy separation. The immobilized enzyme improved the enzymatic activity compared to the free enzyme. In Fe3O4-NH2 and Fe3O4@SiO2-NH2 was observed allows a greater amount of enzyme coupled. [ABSTRACT FROM AUTHOR]

Highlights: [•] m-Phenylenediamine is produced selectively on gold on magnetic supports. [•] Au δ– sites were evidenced on Au/Fe3O4-SiO2. [•] The presence of Fe n+ sites prevents the formation of intermediate hydroxylamines. [•] Au/Fe3O4 and Au/Fe3O4-SiO2 catalysts are magnetically separable and easily recyclable. [Copyright &y& Elsevier]

Gold catalysts supported on ZrO2 and ZrO2-SiO2 were prepared by incipient impregnation and deposition-precipitation with urea (DPU) with 1% of nominal gold loading. The solids were characterized by X-ray diffraction analysis (XRD), N2-physisorption and temperature programmed reduction (TPR). Catalytic activities were investigated in cinnamaldehyde hydrogenation. The selectivity towards the desired product was influenced by the crystalline or amorphous phase support and method of gold deposition. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogenation of cinnamaldehyde (α,β-unsaturated aldehyde) and benzalacetone (α,β-unsaturated ketone) over Au/SiO2 and Ir/SiO2 catalysts was studied. Gold catalyst was prepared by deposition precipitation using NH3·H2O and iridium catalyst was prepared by classical impregnation. The solids were characterized by N2-physisorption, electron microscopy and CO adsorption followed by DRIFTS. Mean particle size (d s ) as determined by TEM was 5.7nm for Au/SiO2 and 3.1nm for Ir/SiO2. For both, cinnamaldehyde and benzalacetone hydrogenation, iridium catalyst was more active than Au/SiO2, but selectivity toward the unsaturated alcohol followed the opposite trend Au/SiO2 being more selective than Ir/SiO2. The results are explained considering particle size effects and surface species on the metal particles. While in the case of gold, particle size and nature of the surface gold species allow explaining the lower activity and observed selectivity, in the case of iridium particle size seems to be more important. The presence of negatively charged gold species favors the selectivity to hydrogenation of the Cce:simple-para> [Copyright &y& Elsevier]

We study the effects of a uniform and constant magnetic field on the Bose–Einstein condensation (BEC) of relativistic charged scalar bosons. The condensation of magnetized charged bosons is usually discussed in the weak or strong field regimes separately, and in each case, the properties predicted for the condensate are different. Here, we develop a low‐temperature analysis suitable for any field that allows us to observe how the gas behaves for intermediate values of the magnetic field. We find that BEC may occur at finite magnetic fields, despite the gas becoming effectively one‐dimensional due to Landau quantization of the momentum perpendicular to the magnetic axis. [ABSTRACT FROM AUTHOR]

Catalytic properties of Sulfated Zirconia (SZ) and Niobium Oxide (NBO), in sucrose inversion reaction to obtain invert sugar were studied. The reaction was performed in two types of solvents: water or water:ethanol (50:50). Materials were analyzed by X-ray Diffraction (XRD), Nitrogen Physisorption, Temperature Programmed Desorption (TPD) and Infrared Spectroscopy (IR). The results showed an important influence of the solvent on the catalytic activity for both catalysts. It was found that SZ had a higher conversion (%) corresponding to 98% in water:ethanol opposite trend than NBO, which exhibited better catalytic activity in water solvent with a conversion (%) of 66%, such behavior can be assigned to the possible conservation of structural stability of each of the catalysts in the solvents used. It was also showed a higher selectivity at 100 % to the interest product when NBO was used, it is attributed to acid-tolerant properties in polar liquids, while SZ caused a consequent degradation of sucrose giving rise to the formation of secondary products of reaction and selectivity (%) around of 80%, due to the significant acidity as showed in the TPD results. [ABSTRACT FROM AUTHOR]

The Pt/SiO2, Pt/Al2O3 y Pt/TiO2 catalysts through wet impregnation at 1% concentration in weigh metal were prepared. The resulting catalysts were characterized by X-ray diffraction (XRD), nitrogen physisorption (77 K) and hydrogen chemisorptions (298 K). Theses catalytic systems were employed in the reaction of m-dinitrobenzene hydrogenation toward m-phenylenediamine. The m-phenylenediamine is aromatic amine used in fine chemicals. The reactions were carried out in batch reactor to hydrogen pressure of 0.82 MPa, 343 K, using ethanol as solvent. The products resulting were analyzed by gas chromatography. The results showed that Pt/TiO2 catalyst had a high level of selectivity toward m-phenylenediamine (72.4 %) and level of conversion of m-dinitrobenzene (91.5 %). This behavior could be attributed to the strong metal-support interaction, as well as this catalyst is promising by production of m-phenylenediamine. [ABSTRACT FROM AUTHOR]

The model of Bohart and Adams was applied to the process of removal of mercury from mine drainage by adsorption with activated carbon in fixed bed columns. For this several drains from coal mines of Guachetá in Colombia, were studied. Once the optimum operating conditions of the column are established, a detailed study of breakthrough curves using the Bohart and Adams model was done, to determine the lifetime of the adsorbent material and the effectiveness of the method for removal the metal ions. It was established that the breakthrough time was 20 min. and the column with the best performance was 1.7 cm in diameter and 2 cm bed length, under the study conditions. The model described the initial part of the breakthrough curve and the parameters of the model allow designing and optimizing the performance of fixed bed adsorption systems for the removal of Hg2+ ions fro aqueous mine wastes. [ABSTRACT FROM AUTHOR]

For charged vector bosons (W bosons) of mass mw, magnetization diverges for B → Bcw, which suggests that if the magnetic field is large enough, it can be self-consistently maintained. For photons bearing an anomalous magnetic moment, having a sufficiently large density, their contribution to magnetization might become of the same order than the applied external field, leading also to self-magnetization. We discuss these models in connection to the case of radiation in equilibrium at high temperature (T ~ mc2) coexisting with hot magnetized electron-positron pairs. [ABSTRACT FROM AUTHOR]

Previous results concerning the arising a tiny photon anomalous paramagnetic moment are also interpreted as a red-shift in analogy to the gravitational known effect. It is due to the photon interaction with the magnetized virtual electron-positron background which withdraw transverse momentum from photons and is polarization-dependent. The photon frequency red-shift implies a change in time and a clock would go faster for increasing magnetic field intensity. [ABSTRACT FROM AUTHOR]

A transformation that relates the Minkowskian space of Quantum Electrodynamics (QED) vacuum between parallel conducting plates and QED at finite temperature is obtained. From this formal analogy, the eigenvalues and eigenvectors of the photon self-energy for the QED vacuum between parallel conducting plates (Casimir vacuum) are found in an approximation independent form. It leads to two different physical eigenvalues and three eigenmodes. We also apply the transformation to derive the low energy photons phase velocity in the Casimir vacuum from its expression in the QED vacuum at finite temperature. [ABSTRACT FROM AUTHOR]

By considering the expression for the total neutrino luminosity, Lν, in terms of the neutrino total emissivity and the volume of a neutron star, we confirm that indeed the luminosity for the direct URCA processes has a dependence on temperature of order T6 as assumed by Heinke and Ho. However, as can be seen in our formulation, Lν depends also on a variety of ingredients that characterize properties of dense nuclear matter as baryon effective masses, Fermi momenta and energy, as well as parameters that characterize the weak interaction beta process. In particular, the dependence of the luminosity of neutrinos in the effective mass of baryons that make up a neutron star opens a new perspective on the study of properties of dense nuclear matter. The model adopted in our calculations may represent, we believe, a further step in elucidating the mysteries surrounding the cooling of Cassiopeia A. Work along this line is in progress [ABSTRACT FROM AUTHOR]

We present a relativistic effective model with derivative couplings which includes genuine many-body forces simulated by nonlinear interaction terms involving scalar-isoscalar (σ, σ*), vector-isoscalar (ω, ɸ), vector-isovector (ϱ), scalar-isovector (δ) mesons. The effective model presented in this work has a philosophy quite similar to the original version of the model with parameterized couplings. But unlike that, in which the parametrization is directly inserted in the coupling constants of the Glendenning model, we present here a method for the derivation of the parametric dependence of the coupling terms, in a way that allows in one side to consistently justify this parametrization and in the other to extend in a coherent way the range of possibilities of parameterizations in effective models with derivative couplings. The extended model is then applied to the description of the mass of neutron stars. [ABSTRACT FROM AUTHOR]

Hydrolyses in D2O (pD 1.7-3.1) of dimethyl (7), methyl phenyl (8), phenyl methyl (9), and diphenyl (10) phosphonoformate diesters are substantially accelerated by Ce(IV), Th(IV), Zr(IV), and Hf(IV) cations. Chemoselectivity is observed, whereby Zr(IV) and Hf(IV) principally direct P-OR hydrolysis, whereas Th-(IV) and Ce(IV) mainly direct C-OR hydrolysis. Leaving group efficiency (OMe vs OPh) modulates the chemoselectivity. The metal cations also mediate further hydrolytic reactions of the initially produced phosphonoformate monoesters 14, 15, 18, and 20. The origins of the P-OR/C-OR selectivity are discussed in terms of the metal cation hydroxo species likely to be present in solution and the kinetics of the reactions. [ABSTRACT FROM AUTHOR]

Explores the consequence of the Human Genome Project in the privacy of the worker and in field of working place relationships and how the Chilean legal system will react to those challenges. Information on the Human Genome Project; Challenges in labor relations and in the protection of the privacy of workers; Mechanisms to protect the privacy of employees.

We discuss the Bose–Einstein condensation of relativistic vector charged particles in a strong external magnetic field in very dense matter, as may be paired spin-up electrons. We show that for electrons such systems may maintain self-consistently magnetic fields of order in between the interval 1010–1013 Gauss. This could be the origin of large magnetic fields in some white dwarfs, but may also impose bounds due to the arising of strong anisotropy in the pressures, which may produce a transverse collapse of the star. [ABSTRACT FROM AUTHOR]

We discuss the effect of a strong magnetic field in the behavior of the symmetry of an electrically neutral electroweak plasma. We analyze the case of a strong magnetic field and low temperatures as compared with the W rest energy. If the magnetic field is large enough, it is self-consistently maintained. Charged vector bosons play the most important role, leading only to a decrease of the symmetry breaking parameter, the symmetry restoration not being possible. [ABSTRACT FROM AUTHOR]

The power balance of EDM systems for discharge pulses of the order of a microsecond was found to be strongly related to cathode material properties [Investigations of physical processes in wire-EDM by means of single and multiple discharge measurements and analysis, Proc. ISEM XIII, vol. 1, 2001, pp. 473–484]. Although such power balance determines the basic material removal and wear performances in wire-EDM and finishing regimes of die-sinking EDM, it still lacks theoretical description and understanding. In this paper we present a model that relates the power balance for EDM electrodes to the current distribution and potential fall through the electrodes discharge system as well as to the thermophysical properties of electrode materials. Based on electrode erosion data for different metal and alloy arrangements, we present and discuss results for the power balance of short single discharges in terms of the spot current density characteristics, including the amplitude of its ionic and electronic components, and the temperature specific to the cathode materials of the system. [Copyright &y& Elsevier]

The era of knowledge economies is inextricably linked with the current wave of globalization, which is asymmetrically benefiting Northern countries and thereby exacerbating the enormous wealth and quality of life gap with their Southern counterparts. Meanwhile, scientists, governments, and commercial institutions in the South arc searching for effective ways to respond. Rather than insisting on developing indigenous technologies when abundant and well-proven technologies already exist, scientists can help choose the right ones and learn how to use them in specific contexts. As science and scientists are crucial in knowledge economies, they are increasingly figuring prominently in government decision-making. The wealth of nations in the era of knowledge economies is not based in their reserve of raw materials, but in their knowledge, research, technology, and innovation capacity. In short, for the Third World in particular, human capacity building is essential. In recent decades, a few Third World nations have experienced humorotis world class scientific and technological achievements. This paper examines a few such national cases as well as makes assessments of necessary measures for nations of the South to advance with science and technology in service of socioeconomic development at the present juncture. [ABSTRACT FROM AUTHOR]

Describes efforts to understand and improve the reactivity of organophosphorus-iodosyl and organophosphorus-iodylcarboxylate derivatives for the degradation of organophosphorus substrates. Structure, bonding and nucleophilic reactivity of organophosphorus-iodosylcarboxylates; reactivity in surfactant systems; Details on microemulsions, functionalized solid supports and latexes.

The novel N-(3,5-bis(trifluoromethyl)benzyl)stearamide 3 was prepared in moderate yield by a solventless direct amidation reaction of stearic acid 1 with 3,5-bis(trifluoromethyl)benzylamine 2 at 140 °C for 24 h under metal- and catalyst-free conditions. This practical method was conducted in air without any special treatment or activation. The fatty acid amide 3 was fully characterized by IR, UV–Vis, 1D and 2D NMR spectroscopy, mass spectrometry, and elemental analysis. Moreover, molecular electrostatic potential studies, determination of quantum descriptors, fundamental vibrational frequencies, and intensity of vibrational bands were computed by density functional theory (DFT) using the B3LYP method with 6-311+G(d,p) basis set in gas phase. Simulation of the infrared spectrum using the results of these calculations led to good agreement with the observed spectral patterns. [ABSTRACT FROM AUTHOR]

Whey in large quantities can cause environmental problems when discarded, because it reduces dissolved oxygen and aquatic life. Nonetheless, it could be used as an easily available and economical alternative to reduce culture medium costs in microbially induced calcium carbonate precipitation (MICP). In this work, a native Sporosarcina pasteurii was isolated and then cultured by using different proportions of whey (W) in nutrient broth (NB). The solids were characterized by XRD, FT-IR, TGA, and SEM. The potential applications in bioconsolidation were also studied. Whey concentration was directly related to CaCO3 production. Higher whey concentrations reduced calcium carbonate purity to nearly 80%. All experiments showed calcite and vaterite fractions, where a whey increment in the media increased calcite content and decreased vaterite content, causing a decrease in crystal size. MICP improved compressive strength (CS) in sand and fly ash. The best CS results were obtained by fly ash treated with 25 W-75 NB (37.2 kPa) and sand with 75 W-25 NB (32.1 kPa). Whey changed crystal polymorphism in biogenic CaCO3 production. Material bioconsolidation depends on the CaCO3 polymorph, thus fly ash was effectively bioconsolidated by crystallization of vaterite and sand by crystallization of calcite. [ABSTRACT FROM AUTHOR]

The self‐assembly of 1,3‐diaminopropane (DAP), 2‐formylphenylboronic acid (FPBA) and 2,3,6,7,10,11‐hexahydroxytriphenylene (HHTP) into a trigonal‐prismatic molecular cage through reversible iminoboronate ester motifs is reported. The organic cage generates solvates with acetonitrile and nitrobenzene, exhibiting vapochromic behavior. Single‐crystal X‐ray diffraction analysis evidenced the inclusion of nitrobenzene within the cage cavity. The resulting host‐guest complex is stabilized by donor‐acceptor‐donor interactions between the nitrobenzene guest and the π electron‐rich HHTP units of the cage. [ABSTRACT FROM AUTHOR]

We reported an efficient one-pot two-step synthesis of 3-(tert-butyl)-N-(4-methoxybenzyl)-1-methyl-1H-pyrazol-5-amine 3 in good yield by a solvent-free condensation/reduction reaction sequence starting from 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and p-methoxybenzaldehyde 2. The one-pot reductive amination proceeded by the formation in situ of the N-(5-pyrazolyl)imine 4 as key synthetic intermediate of other valuable pyrazole derivatives. This methodology is distinguished by its operational easiness, short reaction time, isolation and purification of the aldimine intermediate is not required. The structure of the synthesized N-heterocyclic amine 3 was fully characterized by FTIR-ATR, 1D and 2D NMR experiments, EIMS, and elemental analysis. [ABSTRACT FROM AUTHOR]

The 1,2,3-Triazole derivatives containing the sulfonyl group have proved their biological importance in medicinal chemistry and drug design. In this sense, we describe the regioselective synthesis of 2-(phenylsulfonyl)-2H-1,2,3-triazole 3 in good yield through a classical sulfonamidation reaction of 1H-1,2,3-triazole 1 with benzenesulfonyl chloride 2 in dichloromethane using a slight excess of triethylamine at 20 °C for 3 h. This procedure is distinguished by its short reaction time, high yield, excellent regioselectivity, clean reaction profile, and operational simplicity. The sulfonamide 3 was characterized by high-resolution mass spectrometry, FT–IR, UV–Vis, 1D and 2D NMR spectroscopy, and elemental analysis. The sulfonamide 3 exhibited moderate activity against UO-31 renal, SNB-75 central nervous system, HCT-116 colon, and BT-549 breast cancer cell lines, with growth inhibition percentages (GI%) ranging from 10.83% to 17.64%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption properties of methanol changed as a result of boron incorporation. • Modification of acid/base properties of the surface of the lamellar oxides and catalysts. • Lower carbon deposits on boron-containing catalysts. • Ni/B-LDO shows a different reaction path than Ni/LDO. Methanol decomposition (MD) was studied over nickel supported over layered double oxides (LDO) and layered double oxides modified with B 2 O 3 (B-LDO). Catalysts with nickel metal content ranging from 5 to 20 wt. % were synthesized by the impregnation method, and materials were characterized by atomic absorption, TGA, XRD, HRTEM, FTIR, and N 2 physisorption. The catalytic properties in the MD reaction were studied in the 100−450 °C range. The conversion and selectivity were studied in a conventional flow reactor along with TPSR of methanol followed by GC-QMS. In-situ DRIFTS studied the evolution of adsorbed species. The adsorbed intermediates apparent higher reactivity (methoxy and formate) on boron-containing catalysts corroborated Ni/B-LDO catalysts improved activity. Overall, both nickel and boron modify the methanol interaction with the surface of Ni/B-LDO catalysts, improving its reactivity. [ABSTRACT FROM AUTHOR]

N6-(N'-Arylcarbamoyl)-2'-deoxyadenosine-H-phosphonates displayed molecular recognition towards cationic phenothiazinium and phenoxazinium dyes in aqueous solutions; studies have shown that binding is driven mainly by aromatic interactions and that size and shape-complementarity of the aromatic rings in host and guest provides selectivity. [ABSTRACT FROM AUTHOR]

N6-(N?-Arylcarbamoyl)-2?-deoxyadenosine-H-phosphonates displayed molecular recognition towards cationic phenothiazinium and phenoxazinium dyes in aqueous solutions; studies have shown that binding is driven mainly by aromatic interactions and that size and shape-complementarity of the aromatic rings in host and guest provides selectivity. [ABSTRACT FROM AUTHOR]

Diastereoselective epoxidation of R‐(+)‐limonene using achiral and racemic dimeric Salen‐Mn (III) complexes as catalysts ((1a) and (1b)) and in situ generated dimethyldioxirane (DMDO) as an oxidizing agent was explored. The best reaction parameters were: (i) KHSO5/R‐(+)‐limonene molar ratio = 0.25; (ii) R‐(+)‐limonene, catalyst molar ratio = 20, (iii) absence of nitrogenous bases (axial ligands), (iv) ambient temperature (20°C), (v) racemic dimeric catalyst, and (vi) low amount of acetone (4 mL). Under these reaction conditions isolated yield to 1,2‐(+)‐limonene oxide and diastereomeric excess (d.e), and diastereomeric yield excess (d.y.e) to major diastereomer (cis‐epoxide) was 96%, 77%, and 72%, respectively. Moreover, the catalyst was segregated into a solid phase, while products remained in the liquid phase, allowing the easy separation of the catalyst and reaction products. Consequently, the catalyst could be recycled up to three times without appreciable loss of its initial catalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biogenic CaCO 3 was obtained from Sporosarcina pasteurii isolated from agricultural soils. • CaCO 3 impregnated with Pd 0.5 % was an effective catalyst in the continuous phenylacetylene hydrogenation. • Under optimized conditions, 30 °C, flow rate 1 mL/min and 10 bar pressure, a styrene yield of 65 % was reached. • Pd0.5/CaCO 3 was stable along twelve hours on stream with any decrease in the catalytic performance. CaCO 3 obtained from Sporosarcina pasteurii isolated from agricultural soils has been employed as catalytic support for Pd that was subsequently loaded on CaCO 3 by wet impregnation with a metal loading of 0.5 wt.% using Palladium acetate as precursor. The materials were characterized via nitrogen physisorption measurements, X-ray diffraction, X-ray photoelectronic spectroscopy, TGA Analysis and TEM microscopy. Pd0.5/CaCO 3 was able to successfully hydrogenate phenylacetylene into styrene and ethylbenzene as products. Thus, through the proper optimization of the reaction conditions (flow rate, temperature, pressure) it was possible lead the reaction towards the selective production of styrene, a monomer widely used in the polymer industry, from phenylacetylene as starting material in yields up to 65 %. [ABSTRACT FROM AUTHOR]

• Regioselective and efficient sulfonylation reaction of 1 H -1,2,4-triazol-5-amine. • Spectroscopic and thermal analyses were explained. • N -Heterocyclic sulfonamides displayed moderate cytostatic activity. • Crystallographic, Hirshfeld surface, energy frameworks, and ESP analyses. • Crystal structures describe molecular sheets assembled by short hydrogen bonds. We described a regioselective synthesis of two 1-(arylsulfonyl)-1 H -1,2,4-triazol-5-amines 17 with good yields through a triethylamine-mediated N -sulfonylation reaction of 1 H -1,2,4-triazol-5-amine 15 with arylsulfonyl chlorides 16 in dichloromethane at ambient temperature for 3 h. The N -heterocyclic sulfonamides 17 were characterized by spectroscopy, mass spectrometry, thermal analysis, and single crystal X-ray diffraction (SC-XRD). The SC-XRD analysis showed that compounds 17a and 17b have layered molecular structures, which are assembled through short hydrogen bonds involving N-H‧‧‧N, N-H‧‧‧O, C-H‧‧‧O, and C-H‧‧‧π, and interconnected by π‧‧‧π stacking interactions. For the two triazoles, electrostatic forces are the dominant attracting force within the molecular sheets, while dispersion forces play a more predominant role between the sheets. The packing arrangements were studied by crystallographic analysis and complementarily through computational calculations. Finally, these sulfonamides 17a and 17b demonstrated the most promising in vitro anticancer activity against the SNB-75 and UO-31 cell lines associated with the central nervous system and renal cancer, exhibiting moderate growth inhibition percentages of 18.7 % and 27.2 %, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

The conversion of residual biomass from fruit seeds into biochar can be achieved using MgCl2 as an activating agent and calcining at 700 °C. The resulting MgO‐biochars were employed in the aldol condensation reaction between furfural and acetone. This reaction is essential as the first step in the obtention of biofuels derived from biomass. The biochars were characterized through various physicochemical techniques, revealing that the presence of MgO nanoparticles deposited on the carbon surface modifies the structural and acidic‐basic properties of the carbonaceous materials with a graphitic structure. The biochar with a surface content of MgO of 0.34 % w/w enables the achievement of 100 % of selectivity towards 4‐(2‐furanyl)‐3‐buten‐2‐one (I) with quantitative conversions under optimized conditions. This property highlights the potential of using this type of biochar, commonly used for CO2 capture, as a versatile acidic‐basic catalyst, thereby introducing a novel approach to sustainable chemistry. [ABSTRACT FROM AUTHOR]

The thermodynamic stability of 1 : 1 and 2 : 1 boron–nitrogen (B←N) adducts formed between aromatic boronic esters with mono‐ and diamines was studied in solution by NMR and UV‐vis spectroscopy with association energies (ΔG°) ranging from −11 to −28 kJ mol−1. The effect of different substituents in the boronic ester, the nature of the diamine linker, and the effect of the solvent was explored. Stable 2 : 1 B←N adducts with diamines such as 1,3‐diaminopropane were produced in solutions of hydrogen‐bonding acceptor solvents (acetonitrile and ethyl acetate), which can be isolated in the solid state as crystalline solvates, whereas the use of noncoordinating solvents such as 1,2‐dichloroethane afforded mainly 1 : 1 B←N adducts. In suitable combinations, aromatic bis‐pyridyl diamines produced stable 2 : 1 B←N adducts that were isolated either as solvent‐free solids, solvates, or cocrystals. In these crystalline forms, double‐tweezer hosts were observed with an exceptional syn/anti conformational guest‐adaptability driven by simultaneous donor‐acceptor and C−H⋅⋅⋅π interactions in the tweezer cavities, resembling preorganized covalent tweezer hosts. Interestingly, cocrystals with electron‐rich guests such as tetrathiafulvalene and pyrene showed non‐centrosymmetric crystal lattices with infinite π‐stacked donor–acceptor columns. [ABSTRACT FROM AUTHOR]

Au-ZnO nanomaterials were tested in photodegradation reactions performed under UV-Visible light; Phenol, Catechol and Hydroquinone were selected as target molecules, and it was found that Hydroquinone is the most sensitive molecule to be degraded under illumination. The Au addition significantly increases the photocatalytic activity of ZnO in the degradation of the phenolic compounds and the Au content is an important factor influencing the physicochemical properties of the nanomaterials synthesized and therefore the effectiveness of the photocatalytic treatment. The highest effectiveness in the phenolic compounds elimination was achieved by using ZnO modified by the addition of 2 wt.% of gold, this is due to the highest absorption of this material in the visible region of the electromagnetic spectrum. By HPLC analyzes, it was determined that the degradation route of the phenolic compounds depends on the photocatalyst employed in the catalytic reaction and on the substrate to be degraded, thus, Phenol degradation takes place by formation of more intermediate compounds than the observed in Catechol or Hydroquinone photodegradation. [ABSTRACT FROM AUTHOR]

We study the transverse propagation of photons in a magnetized vacuum considering radiative corrections in the one‐loop approximation. The dispersion equation is modified due to the magnetized photon self‐energy in the transparency region (0 < ω < 2me). The aim of our study is to explore the propagation of photons in a neutron star magnetosphere (described by a magnetized vacuum). The solution of the dispersion equation is obtained in terms of analytic functions. The larger the magnetic field, the higher the phase velocity and the more the dispersion curve deviates from the light‐cone. For fixed values of the frequency, we study the dependence of photons time delay with the magnetic field strength, as well as with distance. For the latter, we adopt a magnetic dipole configuration and obtain that, contrary to the expectation, photons of higher energy experience a longer time delay. A discussion of potential causes of this behavior is presented. [ABSTRACT FROM AUTHOR]

In this article, we analyze the impact of the magnetic field‐dependent boundary conditions on the solutions of the γ‐structure equations for magnetized Bose–Einstein condensate stars (BECs). We consider two cases: pure BECs and BECs surrounded by a magnetic field. As they correspond to different physical situations, they lead to different numerical behaviors, having important effects on the stability of the solutions, as well as on the observables of the star. The differences between the mass–radii curves obtained in each situation are presented and discussed. [ABSTRACT FROM AUTHOR]

This study focuses on the search of new applications of polyoxometalates known as decaniobate ions [Nb10O28]6−. The decaniobates can be used as basic solid catalysts in multicomponent reactions to obtain good yields to 4H-pyrans (> 95%) under microwave radiation and solvent-free conditions, using several aldehydes with different electron-withdrawing or electron donor substituents. The synthesis of (TMA)6 [Nb10O28]6H2O was performed following a simple protocol (HPNb), which was modified to decrease the number of hexaniobate species that are formed as impurities (HPNb-HF). [ABSTRACT FROM AUTHOR]

The Constitution and the Code of Criminal Procedure, as well as international treaties ratified by Chile, oblige the state to offer free legal assistance to those who require it, which is especially relevant in the criminal sphere. On the riots or social unrest that occurred in Chile in the last quarter of 2019 and early 2020, the Public Criminal Defense Office adopted a set of measures to offer legal defense to those who were detained or indicted by the criminal prosecution bodies. This research compares crime behavior in the country between 2017 and 2021 and identifies the social unrest crimes. These are a group of crimes whose frequency increased considerably during the turbulent months: 1) burglary, 2) public disorder, 3) disturbances to public order, and 4) attacks and threats against authorities. The volume and specificities of the social unrest crimes challenged the entire justice sector and, in doing so, made it possible to generate beliefs about the legitimacy of the criminal justice system. In contexts of social unrest, the generation of such beliefs seems especially important, because they can increase perceptions of injustice, enhancing the motivations that give rise to such unrest. Therefore, the operational reactions deployed in the Public Criminal Defense Office to ensure timely criminal defense services are explained. Good practices of the Public Criminal Defense Office that could be strengthened institutionally and normatively so that the justice sector is better prepared to face complex or unusual criminological phenomena, such as those that occurred during the social outburst, are also highlighted. [ABSTRACT FROM AUTHOR]