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The F0 larva of Onychogomphus cazuma, of which only the final exuvia was known, is described, and illustrated for the first time, from materials collected in two locations in the Valencian Community (Spain). The morphological characteristics of the larvae are analysed, and a key is built for the determination of the five species of the genus Onychogomphus present in the Iberian Peninsula and the Maghreb. A key is also provided to separate the genus Gomphus from the genus Onychogomphus, without using the palp structure of the prementum. Additional data about the habitat of the species are provided and a protection figure is proposed at the regional level. [ABSTRACT FROM AUTHOR]

The dual-emissive fluorescent probe described here enabled dynamic tracking of singlet oxygen (1O2)-ROS species production and localization dynamics between the mitochondria and nucleoli in the presence of agents perturbing the mitochondrial membrane potential and under a photodynamic (PDT) system. Local structural information during the probe-1O2 interaction was followed by spectrally resolved confocal microscopy. [ABSTRACT FROM AUTHOR]

Local microviscosity monitoring in living cells is a powerful tool to determine their healthy status in either a specific organelle or in the cytosol. Here is presented the rational design of a new family of self-calibrating dual-microviscosity probes as a strategy to improve the probe response at low viscosity ranges. We found one of the probes is useful to determine low viscosity variations in living cells where subtle stiffening of the rotor group in the probe can increase its viscosity sensitivity. Further X-ray structure analysis, fluorescence anisotropic measurements, and quantum chemical calculations of the electronic excitation by means of a natural transition orbital (NTO) analysis confirmed the observed response. The present work demonstrates that small viscosity variations (0.01–0.1 cP) in cells require improved analytical sensitivity to be properly monitored. [ABSTRACT FROM AUTHOR]

Abstract: The measurement of physicochemical parameters in living cells can provide information on individual cellular organelles, helping us to understand subcellular function in health and disease. While organelle‐specific chemical probes have allowed qualitative evaluation of microenvironmental variations, the simultaneous quantification of mitochondrial local microviscosity (ηm) and micropolarity (ϵm), along with concurrent structural variations, has remained an unmet need. Herein, we describe a new multifunctional mitochondrial probe (MMP) for simultaneous monitoring of ηm and ϵm by fluorescence lifetime and emission intensity recordings, respectively. The MMP enables highly precise measurements of ηm and ϵm in the presence of a variety of agents perturbing cellular function, and the observed changes can also be correlated with alterations in mitochondrial network morphology and motility. This strategy represents a promising tool for the analysis of subtle changes in organellar structure. [ABSTRACT FROM AUTHOR]

Abstract: The measurement of physicochemical parameters in living cells can provide information on individual cellular organelles, helping us to understand subcellular function in health and disease. While organelle‐specific chemical probes have allowed qualitative evaluation of microenvironmental variations, the simultaneous quantification of mitochondrial local microviscosity (ηm) and micropolarity (ϵm), along with concurrent structural variations, has remained an unmet need. Herein, we describe a new multifunctional mitochondrial probe (MMP) for simultaneous monitoring of ηm and ϵm by fluorescence lifetime and emission intensity recordings, respectively. The MMP enables highly precise measurements of ηm and ϵm in the presence of a variety of agents perturbing cellular function, and the observed changes can also be correlated with alterations in mitochondrial network morphology and motility. This strategy represents a promising tool for the analysis of subtle changes in organellar structure. [ABSTRACT FROM AUTHOR]

This study reports the ability of Escherichia coli WDHL to metabolize pentoses commonly found in lignocellulosic hydrolysates to produce bioethanol (EtOH) and biohydrogen (H 2 ). A Central Composite experimental design was used to establish the effects of pH, temperature and total reducing sugars (TRS) from the wheat straw hydrolysate (WSH) on production, production rate and yield of bioethanol and biohydrogen. Optimal conditions for the simultaneous production were pH 8.2, 31 °C and 23.4 g TRS dm −3 . Batch culture was performed with these conditions in a 1 dm 3 bioreactors, obtaining: 8.9 g EtOH dm −3 , 0.050 g EtOH dm −3 h −1 , 0.38 g EtOH g TRS −1 , and 3277.7 cm 3 H 2 , 18 cm 3 H 2 dm −3 h −1 , 140.1 cm 3 H 2 g TRS −1 . The results showed that the pH and the temperature affected the production of both biofuels. This work enriches the information of simultaneous production of bioethanol and biohydrogen by using second-generation substrates. [ABSTRACT FROM AUTHOR]

2-Phenyl-3-hydroxy-4(1H)-quinolone possessing dual fluorescence due to excited-state intramolecular proton transfer (ESIPT) forms stable complex with phenylboronic acid with blue shifted emission maximum in micellar medium of a cationic surfactant even though the compound lacks required for complexation with boronic acids cis -diol structure. No complexation is observed in the presence of neutral or anionic surfactants. Titrations of this complex with polyols including sugars and nucleotides at pH 8 displace free quinolone showing ratiometric response, which allows determination of polyols with detection limits 0.05–1 mM and unusually wide linear dynamic ranges. Another ESIPT dye 2-(2′-hydroxyphenyl)−1H-benzimidazole also lacking cis -diol structure forms equally stable complex with phenylboronic acid and allows ratiometric determination of polyols with similar characteristics. The results of this study demonstrate that blocking ESIPT of signaling molecule by complexation of the receptor with the proton donor group eliminates the low energy emission from tautomeric form but strongly enhances the high energy emission typical for “normal” form of signaling molecule creating a possibility of ratiometric sensing. [ABSTRACT FROM AUTHOR]

Non-classical protomerism of Schiff bases offers several advantages; for example, specific interactions in the –C=N– linkage can be controlled and differentiated because the interactions are not governed by keto–enol tautomerism. Herein, the pH sensing properties of a new protomeric Schiff base probe (S1) are reported. In particular, among several acids, the probe displays significant optical responses upon interaction with hydrochloric acid (HCl). X-ray structural analysis confirmed the existence of an intermolecular interaction with HCl through a –C=N…H–Cl…O– linkage. Moreover, an optical response via a second channel is manifested as photochromic fluorescence behavior. The properties of S1 were investigated by UV-vis and fluorescence spectroscopy in a solution and the solid state. Its strong acidofluorochromic behavior was analyzed and its pKa and UGRAPHIC DISPLAY="INLINE" ID="UGT1" SRC="UGT1"/ values were determined, which revealed a photobasic character. Positive solvatochromism that resulted from specific interactions taking place in S1 was studied using four different solvent scales, namely, Lippert–Mataga, Kamlet–Taft, Catalán and the recently proposed scale of Laurence et al., which yielded consistent results. Finally, theoretical calculations were conducted to analyze the mechanism of the probe in terms of natural transition orbitals (NTOs) and the spatial extent of charge transfer excitations. [ABSTRACT FROM AUTHOR]

The coordination properties and acid–base behavior of 2-[{(1 S ,2 R )-1-hydroxy-1-phenylpropan-2-ylimino}methyl]-4-bromophenol Schiff base probe ( L1 ) were characterized by UV–Vis and fluorescence titrations in water. The dissociation constants for the ligand account for a keto–enamine tautomer at pH 7. Detailed complexation studies were carried out, observing the formation of stable 1:1 complex for Zn 2+ , where a “turn-on” fluorescence effect is obtained. More importantly, no Cu 2+ interference is observed, which is a typical problem for Zn 2+ probes, this is awarded to the keto–enamine tautomeric form of the probe L1 according to UV–Vis and X-ray structure data. Also, the Zn 2+ vs . Cd 2+ ion discrimination for L1 is proved. Finally, TD-DFT theoretical calculations were conducted in order to stablish the detection mechanism of the probe. [ABSTRACT FROM AUTHOR]

Design parameters derived from structure-property relationships play a very important role in the development of efficient molecular-based functional materials with optical properties. Here, we report on the linear and nonlinear optical properties of a fluorene-derived dipolar system (DS) and its octupolar analogue (OS), in which donor and acceptor groups are connected by a phenylacetylene linkage, as a strategy to increase the number of delocalized electrons in the π-conjugated system. The optical nonlinear response was analyzed in detail by experimental and theoretical methods, showing that, in the octupolar system OS, the dipolar effects induced a strong two-photon absorption process whose magnitude is as large as 2210 GM at infrared wavelengths. Solvatochromism studies were implemented to obtain further insight on the charge transfer process. We found that the triple bond plays a fundamental role in the linear and nonlinear optical responses. The strong solvatochromism behavior in DS and OS was analyzed by using four empirical solvent scales, namely Lippert-Mataga, Kamlet-Taft, Catalán, and the recently proposed scale of Laurence et al., finding consistent results of strong solvent polarizability and viscosity dependence. Finally, the role of the acceptor groups was further studied by synthesizing the analogous compound 2DS, having no acceptor group. [ABSTRACT FROM AUTHOR]

BODIPY-derived molecular fluorescent rotors are one of the most useful families of fluorescent probes for the quantitative measurement of microviscosity. Here, we report the photophysical properties of two molecular rotors as ratiometric viscosity sensors, meso-(4-(9H-fluoren-2-yl)ethynyl)phenyl-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (1) and meso-(5-(9H-fluoren-2-yl)ethynyl)thiophen-2-yl-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (2) having two independent chromophores; one (fluorene) is not influenced by viscosity and is used to determine concentration properties, and the other chromophore (BODIPY) acts as a molecular rotor. The fluorescence ratiometric calibration against microviscosity for the most sensitive probe (1), was obtained in a wide linear dynamic range. The sensitivity of the spectroscopic observables for 1 and 2 towards solvent viscosity and the typical analytical interfering solvent polarity and polarizability parameters were investigated by means of two different solvent scales, namely Lippert–Mataga and Catalán, finding consistent results. Quantum chemical calculations were conducted to analyze the probe mechanism in terms of Natural Transition Orbitals (NTOs) and the spatial extent of charge transfer excitations. [ABSTRACT FROM AUTHOR]

Initially known for its deleterious health effects, hydrogen sulfide (H2S) has recently been recognized as a biologically important gas carrier, like nitric oxide and carbon monoxide. H2S is produced endogenously in mammalian cells by enzymatic and non-enzymatic pathways. when it is produced by the enzymatic pathway, its synthesis is carried out from the amino acid L-cysteine through the transsulfuration pathway. It can also be produced endogenously from exogenous compounds that function as H2S donors as, for example, the naturally occurring organic donors found in some plants. Currently, the role of H2S is well known as brain and cardiac protector, and its research as a therapeutic adjuvant in metabolic diseases such as obesity and type-2 diabetes is becoming increasingly important. The objective of this review is to examine how the contribution of donors and precursors of hydrogen sulfide by the diet impacts health and disease. [ABSTRACT FROM AUTHOR]

Background: Coumel tachycardia is an infrequent form of supraventricular tachycardia (SVT) that usually occurs in infants and children. It is a tachycardia mediated by an accessory pathway with retrograde slow conduction that explains the classic ECG pattern with long RP' interval and negative P waves in leads II, III, and aVF. In this study, we describe the clinical course and management of Coumel tachycardia in children. Case report: We conducted a retrospective review of five consecutive pediatric patients, mean age 11 ± 3 years (range 6 to 14). The first episode of SVT was at a mean age of 10.4 ± 4.8 years (range 2 to 14) with a mean evolution of 7.4 ± 9.4 months (range 1 to 24). Pharmacological therapy was unsuccessful despite the combination of antiarrhythmic drugs. The tachycardia was incessant with a density > 85% by 24-hour Holter monitoring; one patient developed tachycardia-induced cardiomyopathy. All children underwent successful radiofrequency catheter ablation, mean 5 ± 3 applications (range 1 to 8) with a single session and with no complications. After a mean follow-up of 24 ± 16 months, all patients were asymptomatic and recurrence-free without antiarrhythmic treatment. Conclusions: Coumel tachycardia is clinically persistent and usually refractory to antiarrhythmic treatment with substantial risk of tachycardia-mediated cardiomyopathy. Catheter ablation is effective and safe in children; thus, it should be indicated promptly and based on individual selection. [ABSTRACT FROM AUTHOR]

Two simple and low cost 2,4-di-tert-butyl-6-[(1-hydroxycyclohexylmethylimino)methyl]phenol (L1) and 2-[{(1-hydroxycyclohexyl)methylimino}methyl]phenol (L2) Schiff base sensors exhibiting selectivity for Zn2+ in water : methanol (95 : 5, v/v, 10 mM HEPES) are described. L1 and L2 display an “off–on” fluorescence effect forming the L1·Zn and L2·Zn complexes, respectively. In the case of L1·Zn, the emission response is quenched by the addition of Cu2+ forming the respective L1·Cu complex; in spite of that, the fluorescence signal can be completely restored only by the addition of tartrate anions (C4H4O62−) forming again L1·Znvia the “off–on” displacement approach. However, in the case of L2·Zn no Cu2+ interference is observed, which is a typical problem for Zn2+ sensors. Here we describe that a very subtle structural change in the ligand during transition from the enol-imine tautomer in L1 to the keto-enamine tautomer in L2 is enough to modulate the Zn2+/Cu2+ selectivity. Also, the Zn2+vs. Cd2+ discrimination for L1 and L2 is proved. Moreover, we found that the interaction between both L·Zn complexes and tartrate anions completely restored the free ligands by the ligand substitution mechanism even in a more efficient association than phosphate anions. Further, a second colorimetric response channel upon addition of Fe2+ was observed for L1 and L2. Then, TD-DFT theoretical calculations were conducted in order to study the efficiency of the sensors to give different responses in the presence of such metal ions. Finally, the L2 sensor successfully detects Zn2+ in Jurkat cells cultured with and without Zn2+ enriched medium. [ABSTRACT FROM AUTHOR]

A simple (R)-(−)-2-phenylglycinol functionalized Schiff base exhibited a dual response to Zn 2+ , Cu 2+ and Fe 2+ ions in water:methanol, (90:10 v/v). The compound displays an “off–on” fluorescent effect with Zn 2+ ions. The emission response decreased with Cu 2+ forming a Cu 2+ /Zn 2+ specie. The fluorescence signal is restored upon addition of sulfide anion (S 2 − ) using the Cu 2+ displacement approach , forming again the Zinc complex. Additionally, the sensor exhibits a second channel (colorimetric) response with Fe 2+ even in the presence of competing Fe 3+ ions. The pH profiles allowed to determine the p K a values and the pH-dependent change in the sensor recognition process. In addition, TD-DFT quantum chemical calculations were implemented to analyze the sensing mechanism by means of Natural Transition Orbital (NTO) analysis. Flow cytometry experiments demonstrated that the sensor successfully detects either exogenous or endogenous (natural) Zn 2+ ions in Jurkat cells with high sensitivity. [ABSTRACT FROM AUTHOR]

Enhancing substrate accessibility is one of the prerequisites for efficient pretreatment and bioconversion of lignocellulosic biomass, for which reducing particle size and increasing porosity have been implemented. Biomass porosity, characterized as the water retention capacity (WRC), increases significantly with the use of a culture filtrate of an H 2 -producing microbial consortium, causing native lignocellulosic fibers to hydrate and swell extensively. This study describes the effects of hydration treatment and particle size on the biodegradability of native wheat straw fibers with regard to direct H 2 production by a microbial consortium. A culture filtrate and tap water were used as hydration media, and particle sizes of 0.212 and 3.35 mm were tested. As a result, biodegradability, measured as H 2 production, doubled when the lignocellulosic substrate was hydrated with the culture filtrate. Also, hydration had a significant impact on H 2 yield, increasing it from 6.8 to 86.5 mL H 2 /g total consumed sugars when the 0.212 mm fibers were first hydrated. H 2 production was higher with coarser particles (3.35 > 0.212 mm), but hydrogen yield improved with finer particles (0.212 > 3.35 mm). Based on our results, particle size and hydration improve the biodegradability of native wheat straw for H 2 production, although hydration with a culture filtrate increased the biomass porosity (measured as WRC), which influenced the biodegradability more than a reduction in particle size. [ABSTRACT FROM AUTHOR]

Seven Schiff base derivatives of 4-dimethylamino-trans-cinnamaldehyde were synthesized in good yield. The structures of all new derivatives were established by IR, 1H, 13C NMR and HRMS experiments and three of them were corroborated by X-ray diffraction studies. Analysis of the supramolecular structures evidenced the presence of strong intermolecular hydrogen bonds (O–H…N) which promote the formation of molecular chains. The linear properties of this series of chromophores were investigated by UV-Vis and fluorescence spectroscopy in solution and in the solid state. The results revealed interesting photochromic properties for compound 2a promoted by a hydrogen bonding interaction in the solid state, which was established by absorption and emission spectra. Further evidence of the specific interactions that take place in compound 2a was obtained by studying the solvent effects observing a solvato- and acidochromic behavior. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and simple synthesis of 3-cyano-2-pyridone derivatives (6a–f) through 3,4-dihydropyridin-2-one oxidation process is described. A greener method to synthesize 3,4-dihydropyridin-2-one has also been developed by rearranging 4H-pyran (4a–f) derivatives in aqueous medium applying H2SO4 as the catalyst source and microwave irradiation. The vasorelaxant activity of 3-cyano-2-pyridone derivatives (6a–f) was proved on isolated thoracic aorta rat rings with and without endothelium (+E and −E, respectively) pre-contracted with noradrenaline (0.1 μM). All compounds exhibited significant concentration-dependent and endothelium-independent vasorelaxant effects being the nitro derivatives (6a and f) and compound 6d the most potent with EC50 of 7, 4.4 and 5 μM, respectively. Finally, a previously described 3D model of the central pore of human L-type calcium channel (LCC), modified to be on agreement with NCBI sequence NP_005174.2 for subunit alpha-1F isoform 1, was used to dock most active compounds. 6a, d and f lowest affinity energy structures were found docked in the same cavity conformed by IS6, IS5, IP and IIS6 helices. Nifedipine lowest energy structure was found in the cavity formed by IIS6, IIS5, IIP and IIIS6. Although nifedipine docked in a different cavity, the superposition of both, allowed us to observe that they were almost the same cavities, indicating that there exist subtle steric differences that lead to a different docking for nifedipine. All compounds docked with similar free energy of binding. [Copyright &y& Elsevier]

Abstract: A simple (R)-(−)-2-phenylglycinol functionalized Schiff base L1 and its characterization as a fluorescent–colorimetric sensor for Hg2+ ion are described. The UV–vis and fluorescence analysis in methanol and aqueous solution show complex formation between L1 and Hg2+ ion with a micromolar association constant. Competition experiments performed for the acetate salts of Hg2+, Zn2+, Co2+, Pb2+, Cd2+, Mn2+, Cu2+, Ni2+, and Ba2+ revealed that compound L1 exhibits high selectivity toward Hg2+ displaying a color change easily detectable by naked-eye and a turn-off fluorescent effect due to a chelation-enhanced quenching (CHEQ) mechanism. Moreover, addition of EDTA to L1–Hg2+ recovers the fluorescence and color offering receptor L1 as a reversible sensor for real-time applications. [Copyright &y& Elsevier]

Yield stress as a function of water content for soils prone to debris flows due to rain is studied in this work. Yield stress is calculated by the slump test in cylindrical geometry by using the relation proposed by Pashias et al. (1996). The advantage of using this method is the quick and easy determination of yield stress. In this case, the test can be done in situ in the zone susceptible to debris flows. Results of yield stress variation as a function of water content are shown for the cerro de Xico zone located in Chalco Valley in México State, which is considered to be vulnerable to landslides by the local authorities. [ABSTRACT FROM AUTHOR]

The present document tries to explain the presence of the denominated Latin American peripheral scientific journals, from an analysis that provides the cover of institutional, technical aspects and of the impulse for the use of information technologies and communication in the alluded journals, taking as a sample five Latin American countries in six specific areas of knowledge. Also, it formulates a series of conclusions and feasible recommendations for possible solutions. [ABSTRACT FROM AUTHOR]

This paper develops a comprehensive comparative and empiric study conducted in four medium size factories belonging to the industrial machinery production. The analysis of the productive processes will be used by the author to interpret the organizational structures resulted from the implementation of modernization policies in the different factories. [ABSTRACT FROM AUTHOR]

Como consecuencia de las reformas estructurales de los primeros años de la década de los noventa, el Perú ha logrado revertir la tendencia decreciente de las exportaciones observada durante la segunda mitad de los ochenta. Además, en 1998 se ha incorporado al APEC, hecho que representa un conjunto de posibilidades para el desarrollo del intercambio comercial. En este artículo se busca identificar qué tipo de productos se han beneficiado de este proceso de reformas y cuáles dependerán, con mayor intensidad, del desarrollo de las potencialidades actuales. Asimismo, se trata de establecer qué factores productivos explican estos resultados. Para ello se efectúan estimaciones econométricas, basadas en un modelo del tipo Hecksher-Ohlin ampliado, a una muestra de países del APEC. Los resultados indican que si bien factores como el stock de capital, el área geográfica y la disponibilidad de tierras para el cultivo y la actividad forestal son significativos para explicar la dinámica de las exportaciones, hay otros en los cuales el gobierno puede influir directamente, como el grado de apertura y el nivel educativo de la población. [ABSTRACT FROM AUTHOR]

This article compares the transnational economic, political, and socio-cultural relations of Colombian migrants residing in two different locations in the United States. The vast majority of these migrants are middle class and originally from large urban areas, which differs from the typical rural origin migrants previously studied by transnational scholars. This study aims at testing some of the conclusions put forward by previous studies by looking at a group whose characteristics depart from earlier case-studies, using a methodology that overcomes some of the above limitations. To do so, They compare the transnational relations of Colombian migrants residing in two different locations in the United States. Literally, Colombia is a country on the move. At least 3-million Colombians, or 8 per cent of the national population of 37-million, now reside outside the national territory. An additional one million, or 3 per cent of the total, have been forcibly displaced within the national territory by an acute civil strife that has been ravaging the country for the last decade.

Subcellular microenvironment plays a crucial role in maintaining cell homeostasis being hydration an essential parameter to monitor the variations of lipid organization in biological membranes. Fluorescent microenvironment‐sensitive probes are stimuli‐responsive molecules and able to change their fluorescence profile according to the microenvironment properties (polarity, hydration, microviscosity and tension). Here we present an organic fluorescent probe, NPM‐1, as a new microenvironmental dye with selective plasma membrane localization in live cells. Using high‐resolution confocal microscopy and fluorescence spectroscopy, we explored the hydration and polarity variations during the formation of apoptotic bodies in real time. To have a clear understanding of the cell microenvironment variations, an analogue polarity probe able to localize the cytosol and nucleoli was also synthetized, CellPol‐1. Then, we were able to monitor the subcellular hydration variations during the apoptotic body dynamics. [ABSTRACT FROM AUTHOR]

Polymeric nanocarriers (PNs) have demonstrated to be a promising alternative to treat intracellular infections. They have outstanding performance in delivering antimicrobials intracellularly to reach an adequate dose level and improve their therapeutic efficacy. PNs offer opportunities for preventing unwanted drug interactions and degradation before reaching the target cell of tissue and thus decreasing the development of resistance in microorganisms. The use of PNs has the potential to reduce the dose and adverse side effects, providing better efficiency and effectiveness of therapeutic regimens, especially in drugs having high toxicity, low solubility in the physiological environment and low bioavailability. This review provides an overview of nanoparticles made of different polymeric precursors and the main methodologies to nanofabricate platforms of tuned physicochemical and morphological properties and surface chemistry for controlled release of antimicrobials in the target. It highlights the versatility of these nanosystems and their challenges and opportunities to deliver antimicrobial drugs to treat intracellular infections and mentions nanotoxicology aspects and future outlooks. [ABSTRACT FROM AUTHOR]

• 1-Methyl-2-phenyl-3-hydroxy-4(1 H)-quinolone (LH) is a powerful ligand for metal ions. • Fluorescence is changed in order ML > HL > ML 2 with M = Al3+, Ga3+ and Me 2 Sn2+. • Natural Transition Orbital analysis applied to LH, AlL2+ and AlL 2 + explains the trend. Aza-flavonols are compounds containing the 3-hydroxy-4(1 H)-quinolone moiety, a unique scaffold with applications expanding from fluorescent probes and bioimaging to potential metal-related pharmaceutical drugs. Compositions and stability constants of metal complexes of an aza-flavonol 1-methyl-2-phenyl-3-hydroxy-4(1 H)-quinolone (LH) in aqueous micellar medium of hexadecyltrimethylammonium bromide were established by fluorescence and spectrophotometric titrations of LH in the presence of metal ions of different type at variable pH. Strong binding with quenching of ligand fluorescence was observed for Cu2+, Fe2+/3+ and Pb2+ cations. The complexation with Zn2+ induced strong fluorescence enhancement in ZnL+ complex and smaller enhancement in ZnL 2 complex. Al3+, Ga3+ and Me 2 Sn2+ cations induced strong fluorescence enhancement in 1:1 ML complexes, but quenching in ML 2 complexes. Together with the relevant literature data these results indicate that the quenching effect in 1:2 complexes along with strong fluorescence enhancement in respective 1:1 complexes is a general phenomenon for 3-hydroxypyranone and 3-hydroxypyridinone ligands. The quantum mechanical Natural Transition Orbital analysis of ground and excited states of LH, AlL2+ and AlL 2 + species reveals that the fluorescence of AlL 2 + complex is quenched by an internal electron transfer process, which is absent in the 1:1 AlL2+ complex. The results emphasize strong dependence of the coordination induced fluorescence changes on the complex composition. [ABSTRACT FROM AUTHOR]

This study introduces a paradigm-shifting approach to optimize mitochondrial targeting. Employing a new fluorescent probe strategy, we unravel a combined influence of both Nernst potential (ψ) and partitioning (P) contributions. Through the synthesis of new benz[e]indolinium-derived probes, our findings redefine the landscape of mitochondrial localization by optimizing the efficacy of mitochondrial probe retention in primary cortical neurons undergoing normoxia and oxygen--glucose deprivation. This methodology not only advances our understanding of subcellular dynamics, but also holds promise for transformative applications in biomedical research and therapeutic development. [ABSTRACT FROM AUTHOR]

Mitochondrial voltage dynamics plays a crucial role in cell healthy and disease. Here, a new fluorescent probe to monitor mitochondrial early voltage variations is described. The slowly permeant probe is retained in mitochondria during measurements to avoid interferences from natural membrane potential by incorporating an hydrolizable ester function. Voltage, local polarity, pH parameters and transmembrane dynamics were found to be deeply correlated opening a approach in mitochondrial sensing. [ABSTRACT FROM AUTHOR]

The lithium-sulfur (Li-S) system is a promising candidate for the next generation of lithium batteries; however, for practical applications, there are still problems to solve as the loss of active material due to polysulfides diffusion and migration (shuttle effect), passivation of interfaces of both electrodes by deposition of insulating species. Chitosan, as an abundant and sustainable biopolymer has been previously modified to solve issues related to polysulfides retention through biopolymer functionalization; however, the effect of such modifications on the mechanical properties, related to the structural modifications, has been poorly investigated; moreover, the coupled effects of both phenomena, polysulfide trapping capacity and mechanical properties, and its impact on battery capacity and cyclability has not been discussed. In order to determine those effects, in this work is proposed a new binder based on chitosan modified by Methanesulfonic Acid as a plasticizer in the fabrication of sulfur cathodes for Li-S batteries. The improvement in the overall performance of the system was investigated by C-Rate, deep cycling and tensile test, and the results were compared with those of the sulfur cathode using brittle and water-insoluble pristine chitosan as binder. Our results indicated that the Chitosan – Methanesulfonic Acid, ChMSA25 polymer network, is able to modulate the mechanical strength and binding performance of the system. Due to the aforementioned characteristics, the ChMSA25 based sulfur cathode exhibits a low-capacity fade (0.058% per cycle) at 1.0 C for 500 cycles. Therefore, the ChMSA25 binder is a promising candidate for the development of high-performance, water processable lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Lignocellulosic-based production of bio-hydrogen (H 2) by Escherichia coli requires efficient consumption of pentoses and hexoses. However, carbon catabolite repression (CCR) causes sequential utilization of carbohydrates and in some cases null consumption of less preferred carbohydrates, such as xylose. In this work, we evaluated the effect of elimination of the phosphotransferase system (PTS), responsible for CCR in strain E. coli WDH (Δ hycA) on H 2 production using mixtures of glucose-xylose as carbon source. Elimination of ptsG gene (glucose permease-enzyme IIB), allowed simultaneous consumption of glucose and xylose, and improved H 2 production 1.2-times with respect to the parenteral strain. Whereas, elimination of ptsG gene in combination with deletion of ldhA (d -lactate dehydrogenase) and/or frdD (fumarate reductase) genes, improved H 2 production 2.5-times with a H 2 yield of 0.27 mol·C-mol−1, using mixtures of glucose/xylose or wheat straw hydrolysate. Interestingly, besides the improvement on H 2 production, E. coli WDH-GFA (Δ hycA, Δ ptsG, Δ frdD, Δ ldhA) strain also produced ethanol as the main carbon by-product. These results show that elimination of ptsG , in combination with a modified central carbon metabolism improves the production of H 2. • The ptsG gene deletion promoted glucose-xylose utilization in E. coli WDH. • The ptsG gene deletion improved H 2 production in E. coli WDH. • This is first report using a mixture of glucose-xylose for H 2 production by E. coli. • E. coli WDHGFA produced simultaneously ethanol-H 2 using wheat straw hydrolysate. [ABSTRACT FROM AUTHOR]

Mexico is one of the largest agricultural producers in Latin America and generates a large amount of agricultural residue. The aim of this study was to establish the usefulness of four of the main Mexican crops (corn, wheat, sugarcane, and Agave) as feedstock for lignocellulosic bioethanol production. The lignocellulosic residue ratio (RR), defined as weight of residue (in tons) per ton of product, was measured by sampling crop fields in 11 geographic regions of Mexico. The chemical composition, assessed by Fourier‐transform infrared spectroscopy (FTIR) and carbon‐13 nuclear magnetic resonance (13C NMR), and structural composition (extractives, cellulose, hemicellulose, and lignin contents), heating value, and metal content of these lignocellulosic residues were measured. Biorefinery locations, and their theoretical bioethanol production, were suggested using the gravity center method and techno‐economic criteria. The highest RR (1.1 ton of straw per ton of grain) was obtained for wheat straw followed by corn (0.8 ton of stover per ton of grain), sugar cane (0.15 ton of bagasse per ton of cane), and Agave (0.2 ton of bagasse per ton of stem). The composition of these biomasses varied significantly depending on the parental material in extractive compounds, lignocellulosic matter, ashes, hemicellulose, lignin, O‐alkyl C, aromatic C, and carboxyl C. The cellulose crystallinity index and the heating value exhibited small variations among biomasses. Copper, Zn, Cd, and Ni content in the biomasses generally exceeded the European Norm (EN‐Plus FprEN 1496 1‐2 B) for solid biofuels. In total, these agricultural biomasses could be used as feedstock for 34 biorefineries in Mexico with a total bioethanol production potential of approximately 1246 million L year–1. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

A strategy for cancer treatment was implemented, based on chemo-photodynamic therapy, utilizing a novel formulation, low-cost system called Cas-ZnONPs. This system consisted of the incorporation of Casiopeina III-ia (CasIII-ia), a hydrophilic copper coordination compound with well-documented anti-neoplastic activity, on Zinc oxide nanoparticles (ZnONPs) with apoptotic activity and lipophilicity, allowing them to permeate biological barriers. Additionally, ZnONPs exhibited fluorescence, with emission at different wavelengths depending on their agglomeration and enabling real-time tracking biodistribution. Also, ZnONPs served as a sensitizer, generating reactive oxygen species (ROS) in situ. In in vitro studies on HeLa and MDA-MB-231 cell lines, a synergistic effect was observed with the impregnated CasIII-ia on ZnONPs. The anticancer activity had an increase in cellular inhibition, depending on the dose of exposure to UV–vis irradiation. In in vivo studies utilized zebrafish models for xenotransplanting stained MDA-MB-231 cells and testing the effectiveness of Cas-ZnONPs treatment. The treatment successfully eliminated cancer cells, both when combined with Photodynamic Therapy (PDT) and when used alone. However, a significantly higher concentration (50 times) of Cas-ZnONPs was required in the absence of PDT. This demonstrates the potential of Cas-ZnONPs in cancer treatment, especially when combined with PDT. A new nanoformulation that works as a theranostic system, Cas-ZnONPs has emission at different wavelengths and presents two different synergistic effects, between its components: ZnO nanoparticles and Casiopeina III-ia, and an additional one in the presence of PDT. The anticancer activity was studied in zebrafish, achieving the elimination of xenotransplanted MDA-MB-231 cells. [Display omitted] • Zinc oxide nanoparticles as carriers for an inorganic antineoplastic, Casiopeina III-ia. • Real-time bioimaging studies through ZnO fluorescence at different wavelengths. • Synergetic anticancer activity between ZnO nanoparticles and Casiopeina III-ia. • A second synergistic anticancer activity with Cas-ZnONPs and photodynamic therapy. • In zebrafish the theranostic compound eliminated xenotransplanted cancer cells. [ABSTRACT FROM AUTHOR]

Wheat straw is gaining importance as a feedstock for the production of biofuels and high value-added bioproducts. Several pretreatments recover the fermentable fraction involving the use of water or aqueous solutions. Therefore, hydration properties of wheat straw fibers play an important role in improving pretreatment performance. In this study, the water retention capacity (WRC) and swelling of wheat straw fibers were studied using water, propylene glycol (PPG) and an effluent from a H2-producing reactor as the hydration media with three particle sizes (3.35, 2.00 and 0.212 mm). The effects of swelling were analyzed by optical and confocal laser scanning microscopy (CLSM). The highest WRC was reached with the effluent medium (9.84 ± 0.87 g g−1 in 4 h), followed by PPG (8.52 ± 0.18 g g−1 in 1 h) and water (8.74 ± 0.76 g g−1 in 10 h). The effluent hydration treatment had a synergic effect between the enzymes present and the water. The particle size had a significant effect on the WRC (P < 0.01), the highest values were reached with 3.35 mm fibers. The CLSM images showed that finer fibers were subjected to a shaving effect due to the grinding affecting its capacity to absorb the hydration medium. The microscopic analysis showed the increase in the width of the epidermal cells after the hydration and a more undulating cell wall likely due to the hydration of the amorphous regions in the cellulose microfibrils. The sugar release was determined, achieving the highest glucose content with the effluent hydration treatment. [ABSTRACT FROM AUTHOR]

Fluorophore chemistry is at the forefront of bioimaging, revolutionizing the visualization of biological processes with unparalleled precision. From the serendipitous discovery of mauveine in 1856 to cutting-edge fluorophore engineering, this field has undergone transformative evolution. Today, the synergy of chemistry, biology, and imaging technologies has produced diverse, specialized fluorophores that enhance brightness, photostability, and targeting capabilities. This review delves into the history and innovation of fluorescent probes, showcasing their pivotal role in advancing our understanding of cellular dynamics and disease mechanisms. We highlight groundbreaking molecules and their applications, envisioning future breakthroughs that promise to redefine biomedical research and diagnostics. Conceptually innovative fluorophores represent groundbreaking molecules enabling precise and efficient cellular imaging. [Display omitted] • The evolution of fluorophores is traced from the 1856 discovery of mauveine to modern innovations in fluorophore engineering. • Synergistic advances in chemistry, biology, and imaging technologies yield specialized fluorophores with enhanced targeting. • Innovative fluorescent probes are introduced, highlighting groundbreaking molecules and their roles in cellular dynamics. • The revolution in fluorophore chemistry has transformed bioimaging, enabling precise visualization of biological processes. • Upcoming advances in fluorophore chemistry are analyzed, promising to redefine biomedical research and diagnostics. [ABSTRACT FROM AUTHOR]

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. Las papas juegan un papel como verdura o como guarnición en la dieta Mexicana. Son consumidas principalmente en fresco. En sopas se usan vegetales deshidratados de interés particular en la preparación de mezclas secas. La rápida expansión en la industria de la comida rápida pudiera resultar en un aumento en el uso de papas deshidratadas, como un componente de mezcla de vegetales y sopas. No obstante, los tratamientos de pre-secado, como la adición de antioxidantes, son necesarios para el deshidratado de verduras como la papa, a fin de evitar cambios de color. En este trabajo, se investigó la influencia de diferentes pre-tratamientos y condiciones de secado en las características físicas (contenido de humedad, actividad del agua y diferencia en color) de papa rebanada muy delgada durante el deshidratado mediante cama fluidizada. Las muestras de rebanadas delgadas de papa fresca fueron inmersas en soluciones que contenían ácido cítrico (0, 0.5, y 1% p/v) antes del secado. Las muestras de papa se deshidrataron a temperaturas del aire de 40, 50, y 60 °C. Se usó un modelo polinomial de segundo grado para describir las variables-respuestas. El análisis de varianza (ANAVA) para todos los modelos codificados indicaron que los modelos fueron estadísticamente significativos ( p≤0.05). El aumento en la temperatura y el ácido cítrico incrementan la diferencia en color y disminuyen el contenido de humedad y actividad del agua de las muestras deshidratadas de papa. En algunos tratamientos se obtuvo un color cercano al original de la papa fresca. En general, se observó que el secado de rebanadas finas de papa estuvo influenciado por el pre-tratamiento. [ABSTRACT FROM AUTHOR]

The purpose of this work was to determine the influence of air temperature, sample diameter and antioxidants on water activity, moisture content and colour difference of thinly sliced mango in a fluidized bed and tray dryer. Mango samples were treated with antioxidants solutions (ascorbic and citric acid) before the drying process. Fluidized bed and tray drying of control and treated samples were carried out at two temperatures: 50 and 60 °C. A fractional factorial design 2 was used in both drying methods. The Newton semi-theoretical model was found to represent thin-layer drying kinetics of mango. For both drying types, moisture content of thinly sliced mango was well characterised ( R ≥ 0.975) by the model. The temperature increment increases the drying constant and decreases the equilibrium moisture content and water activity of the dehydrated samples. Colour closest to the original colour of fresh mango was obtained when 2 cm diameter mango pretreated with citric acid (1%) was dehydrated by fluidized bed at 60 °C. In addition, it was observed that the drying time at equilibrium by using fluidized bed was lower (60 min) than the tray dryer (120 min). [ABSTRACT FROM AUTHOR]

Congenital coronary artery fistulas are uncommon anomalies, however themselves may resemble the whole spectrum of cardiac manifestations. Clinical presentations vary considerably from adults to children. Material and methods: patients with coronary artery fistula diagnosed by selective coronariography in the period from 2000 to 2007 were included. Results 7 cases were found, 4 children, mean age 6.5 years, and 3 adults, mean age 25.6 years. The fistulae originate from the left coronary artery in 3 children, 2 connect to the pulmonary artery an one to the right atrium, in one child the fistula originated from the right coronary artery and terminated at the right ventricle. In the 3 adult patients, the fistula originated from the right ventricle, two connected to the right ventricle and one to the coronary sinus. Two children were operated on successfully and are asymptomatic 1 and 4 years later. In an adult patient with surgical ligation was performed, 4 weeks later developed an uncomplicated myocardial infarction. We reviewed the literature available and were compared with our cases. Conclusions: The clinical manifestations and hemodynamic features differ in childhood and adulthood. Coronary angiography is the primary diagnostic tool. Surgical treatment has low mortality and morbidity. [ABSTRACT FROM AUTHOR]

Abstract: Saturated straight- and branched-chain 3-hydroxy fatty acids (3-OH FAs) of 10–18 carbon chain lengths were determined in saliva from 27 individuals with chronic periodontitis and 18 healthy individuals by using gas chromatography–tandem mass spectrometry. Of the 14 different 3-OH FAs detected, 3-OH-Ci17:0 was the most abundant in the periodontitis samples while 3-OH-C14:0 was the most abundant in the healthy individuals. Considering the relative percentages of 3-OH-C12:0, 3-OH-C14:0, 3-OH-Ci17:0, and 3-OH-C17:0, 95.6% of all cases were correctly classified as healthy individuals or periodontitis patients by means of discriminant analysis. The sensitivity, specificity, positive predictive value and negative predictive value of 3-OH FA analysis in diagnosing peridontitis were, respectively, 0.92, 1.00, 1.00, and 0.90. The results indicate that 3-OH FA analysis of saliva samples is a useful diagnostic method in chronic periodontitis. [Copyright &y& Elsevier]

Two PcSnIV dicarboxylate molecules were obtained through efficient microwave methodology with the aim to test them as corrosion inhibitors in the oil industry. The compounds were characterized by elemental analysis, IR, UV-vis, ¹H, 13C NMR, and X-ray diffraction. The relative configuration of the two carboxylates is cis, placing the fatty acid moieties on the same face of the phthalocyanine macrocycle. In the solid-state the tin atoms possess square antiprismatic octacoordinated geometries. Both tin phthalocyanines were tested as corrosion inhibitors for hydrogen sulfide corrosive media showing a chemisorption process of the nanocap motifs on the metallic surface. Apparently, the length of the hydrophobic chain contributes significantly to the inhibition efficiency, in the sense that shorter chains increase the efficiency. [ABSTRACT FROM AUTHOR]

A set of BODIPY‐carboranyl dyads synthesized by a Sonogashira cross‐coupling reaction, where different C‐substituted ortho‐ and meta‐carboranyl fragments have been linked to a BODIPY fluorophore is described. Chemical, photophysical and physicochemical analyses are presented, including NMR and single XRD experiments, optical absorption/emission studies and partition coefficient (log P) measurements. These studies, supported by DFT computations (M06‐2X/6‐31G**), provide an explanation to the largely divergent cell income that these fluorescent carboranyl‐based fluorophores display, for which a structural or physicochemical explanation remains elusive. By studying the cell uptake efficiency and subcellular localization for our set of dyads on living HeLa cells, we tracked the origins of these differences to significant variations in their static dipole moments and partition coefficients, which tune their ability to interact with lipophilic microenvironments in cells. Remarkably, m‐carboranyl‐BODIPY derivatives with a higher lipophilicity are much better internalised by cells than their homologous with o‐carborane, suggesting that m‐isomers are potentially better theranostic agents for in vitro bioimaging and boron carriers for boron neutron capture therapy. [ABSTRACT FROM AUTHOR]