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The bacterial archetypal adaptive immune system, CRISPR-Cas, is thought to be repressed in the best-studied bacterium,Escherichia coliK-12. We show here that theE. coliCRISPR-Cas system is active and serves to inhibit its nine defective (i.e., cryptic) prophages. Specifically, compared to the wild-type strain, reducing the amounts of specific interfering RNAs (crRNA) decreases growth by 40%, increases cell death by 700%, and prevents persister cell resuscitation. Similar results were obtained by inactivating CRISPR-Cas by deleting the entire 13 spacer region (CRISPR array); hence, CRISPR-Cas serves to inhibit the remaining deleterious effects of these cryptic prophages, most likely through CRISPR array-derived crRNA binding to cryptic prophage mRNA, rather than through cleavage of cryptic prophage DNA; i.e., self-targeting. Consistently, four of the 13E. colispacers contain complementary regions to the mRNA sequences of seven cryptic prophages, and inactivation of CRISPR-Cas increases the level of mRNA for lysis protein YdfD of cryptic prophage Qin and lysis protein RzoD of cryptic prophage DLP-12. Also, lysis is clearly seen via transmission electron microscopy when the whole CRISPR-Cas array is deleted, and eliminating spacer #12, which encodes crRNA with complementary regions for DLP-12 (includingrzoD), Rac, Qin (includingydfD), and CP4-57 cryptic prophages, also results in growth inhibition and cell lysis. Therefore, we report the novel results that (i) CRISPR-Cas is active inE. coliand (ii) CRISPR-Cas is used to tame cryptic prophages, likely through RNAi; i.e., unlike with active lysogens, active CRISPR-Cas and cryptic prophages may stably co-exist.

The transient current technique (TCT) is widely used in the field of silicon particle detector development. So far, only laser wavelengths with a photon energy larger than or similar to the silicon bandgap (single photon absorption) were used. Recently, measurements using two-photon absorption (TPA) for silicon detector testing have been carried out for the first time. Excess carriers are only created at the focal point of the laser beam and thus resolution in all three spatial directions could be achieved. The resolution perpendicular to the incident laser beam could be increased roughly by a factor of 10. First measurements using this new method were performed at the Singular Laser Facility of Universidad del País Vasco (UPV)/Euskal Herriko Unibertzitatea (EHU). Following the initial success of the method, a compact TPA-TCT setup is under development. A first description of the setup and laser system is presented in this article., This work was supported in part by the Spanish Ministry of Economy and Competitiveness (MINECO) under Grant FPA2013-48387-C6-1-P and in part by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Research under Grant 05E15CHA.

Carbon nitride based materials incorporating K and Na alkali ions were used as support(s) to deposit platinum. The systems were tested in the photo-production of hydrogen using methanol as a sacrificial molecule. Tests under UV and sunlight-type illumination conditions showed an important promoting effect of the alkali ions irrespective of the illumination source characteristics. The measurement of the quantum efficiency was used to quantitatively assess the performance of the catalysts. Outstanding results were obtained, particularly under sunlight illumination. A complete characterization study of the materials was carried out to establish a structure-activity link. This link correlates catalytic activity with the capture of charge carrier species by surface cyano groups directly associated with the presence of alkali ions at the carbon nitride component.

The combination of thermal and photonic energy sources to carry out catalyzed chemical reactions appears as a new avenue to optimize the current industrial-oriented processes as well as to open new ones. Herein, we analyze the contribution of novel oxide-based composite systems to the thermo-photocatalysis field. In the first place, the review article gives a brief introduction about the physicochemical framework to interpret the thermo-photocatalytic properties of oxide-based solids. From this point and to provide an overview of the progress of the field, we classify the oxide-active catalysts in three main categories considering materials with catalytic properties primarily governed by plasmonic, defect-related, and thermal effects. For each type of system, we analyze the representative oxide systems and the corresponding composite systems, emphasizing the study on the interpretation of the catalytic behavior. The contribution ends with a summary of the current status and an outlook into the future of the field.

Fernandez-Sanjurjo, M, Diaz-Martinez, AE, Diez-Robles, S, Gonzalez-Gonzalez, F, de Gonzalo-Calvo, D, Rabadan, M, Davalos, A, Fernandez-Garcia, B, and Iglesias-Gutierrez, E. Circulating microRNA profiling reveals specific subsignatures in response to a maximal incremental exercise test. J Strength Cond Res XX(X): 000-000, 2020-Circulating microRNAs (c-miRNAs) have been described as emergent regulators and biomarkers of exercise. The aim of this study was to analyze the c-miRNA response to a maximal incremental exercise test (MIET) and its relationship with markers of exercise response and adaptation. Two blood samples were collected from 9 male amateur runners (31-50 years), before (Pre) and after (Post) a MIET. The maximal oxygen uptake (V[Combining Dot Above]O2max), maximum heart rate (HRmax), and maximal aerobic speed (MAS) were recorded. Lactate and creatine kinase (CK) plasma concentrations were measured. A panel of 752 miRNAs was analyzed using standardized protocols and relative quantification to Pre. A total of 13 miRNAs were found significantly upregulated at Post. By focusing on the exercise markers that correlate with the expression of these miRNAs, they were clustered into different functional groups or subsignatures. Thus, miR-21-5p, miR-29b-3p, and miR-183-5p showed a strong correlation with HRmax and a validated target signature related to fatty acid metabolism. Furthermore, let-7c-5p, miR-340-5p, miR-425-3p, and miR-629-5p were significantly correlated with CK, and the most significantly enriched pathways for these subsignatures were the Hippo signaling pathway and signaling pathways regulating pluripotency of stem cells. Finally, Pre miR-106b-5p expression showed an inverse association with MAS and Post lactate concentration, which highlights its relevance as biomarker of training status and its predictive value for performance. No significant correlations were observed with V[Combining Dot Above]O2max. Our results define for the first time specific functional c-miRNA subsignatures, adding novel evidence about their potential regulatory role in exercise response.

Background: Monoclonal protein (M-protein) concentrations are measured by serum protein electrophoresis (SPE). Two methods are used for demarcating the M-protein area in the electropherogram: perpendicular drop (PD) and tangent skimming (TS). The aim of this study was to compare both methods and to establish which is the most accurate and precise. Methods: We studied 24 sera containing M-protein (5-44 g/L). The systematic error (SE) was evaluated in a dilution series of 12 sera. Within-day, between-day, and interobserver variability were assessed. SPE was performed by capillary and agarose gel electrophoresis. M-protein concentrations were measured using both cutoff methods. Results: The PD method shows a constant SE ranged 1.00-2.27 g/L, while constant SE for TS is ranged - 0.30-- 0.57 g/L. None of the cutoff methods or electrophoretic methods showed a proportional SE, with the exception of the TS method in capillary electrophoresis for beta-migrating M-protein. The PD method was more precise than the TS method in all three estimates of imprecision. An increased CV for concentrations < 10 g/L in between-day imprecision was observed with the TS method. Interobserver imprecision was greater for M-protein concentrations < 17 g/L for both cutoff methods (14.85%, 26.42% respectively). Conclusions: Despite being less precise, the TS method provides a more accurate measurement of M-protein concentration.

Many food items included in the Mediterranean diet (MedDiet) are rich in polyamines, small aliphatic amines with potential cardioprotective effects. The consumption of a MedDiet could increase polyamine concentrations. Based on experimental models, polyamine concentrations may be also influenced by physical activity (PA).We aimed to evaluate whether an intervention based on an energy-restricted MedDiet (er-MedDiet) and PA promotion, in comparison with an energy-unrestricted MedDiet and traditional health care, influences the serum pattern of polyamines and related metabolites in subjects at high risk of cardiovascular disease (CVD).This was a substudy from the PREDIMED-Plus trial, an ongoing randomized clinical trial including 6874 participants allocated either to an intensive weight-loss lifestyle intervention based on er-MedDiet, PA promotion, and behavioral support (er-MedDiet + PA group), or to an energy-unrestricted MedDiet and traditional health care group (MedDiet group). A total of 75 patients (n = 38, er-MedDiet + PA group; n = 37, MedDiet group) were included in this study. Serum concentrations of arginine, ornithine, polyamines, and acetyl polyamines at baseline and 26 wk of intervention were measured by an ultra-high-performance LC-tandem MS platform.At week 26, study groups had similar adherence to the MedDiet but patients randomly assigned to the er-MedDiet + PA group showed significantly lower mean energy intake (-340.3 kcal/d; 95% CI: -567.3, -113.4 kcal/d; P = 0.004), higher mean PA (1290.6; 95% CI: 39.9, 2541.3 metabolic equivalent tasks · min/d; P = 0.043), and higher mean decrease in BMI (in kg/m2) (-1.3; 95% CI: -1.8, -0.6; P 0.001) than the MedDiet group. However, no significant differences in serum polyamines or related metabolites were found between study groups after 26 wk of intervention and no significant between-group differences were found in glycated hemoglobin, HDL-cholesterol, or triglyceride concentrations.In individuals at high CVD risk, an er-MedDiet with increased PA did not result in significant changes of serum concentrations of polyamines or related metabolites in comparison with an energy-unrestricted MedDiet and no increase in PA. This trial was registered at isrctn.com as ISRCTN89898870.

The mechanisms whereby Mycobacterium tuberculosis (Mtb) rewires the host metabolism in vivo are surprisingly unexplored. Here, we used three high-resolution mass spectrometry platforms to track altered lung metabolic changes associated with Mtb infection of mice. The multiplatform data sets were merged using consensus orthogonal partial least squares-discriminant analysis (cOPLS-DA), an algorithm that allows for the joint interpretation of the results from a single multivariate analysis. We show that Mtb infection triggers a temporal and progressive catabolic state to satisfy the continuously changing energy demand to control infection. This causes dysregulation of metabolic and oxido-reductive pathways culminating in Mtb-associated wasting. Notably, high abundances of trimethylamine-N-oxide (TMAO), produced by the host from the bacterial metabolite trimethylamine upon infection, suggest that Mtb could exploit TMAO as an electron acceptor under anaerobic conditions. Overall, these new pathway alterations advance our understanding of the link between Mtb pathogenesis and metabolic dysregulation and could serve as a foundation for new therapeutic intervention strategies. Mass spectrometry data has been deposited in the Metabolomics Workbench repository (data-set identifier: ST001328).

Plant growth-promoting rhizobacteria (PGPR) are widely used to improve plant nutrient uptake and assimilation and soil physicochemical properties. We investigated the effects of bacterial (Bacillus megaterium strain DU07) fertilizer applications in a eucalyptus (clone DH32-29) plantation in Guangxi, China in February 2011. We used two types of organic matter, i.e., fermented tapioca residue (“FTR”) and filtered sludge from a sugar factory (“FS”). The following treatments were evaluated: (1) no PGPR and no organic matter applied (control), (2) 3 × 109 CFU/g (colony forming unit per gram) PGPR plus FS (bacterial fertilizer 1, hereafter referred to as BF1), (3) 4 × 109 CFU/g plus FS (BF2), (4) 9 × 109 CFU/g plus FS (BF3), (5) 9 × 109 CFU/g broth plus FTR (BF4). Soil and plant samples were collected 3 months (M3) and 6 months (M6) after the seedlings were planted. In general, bacterial fertilizer amendments significantly increased plant foliar total nitrogen (TN) and soil catalase activity in the short term (month 3, M3); whereas, it significantly increased foliar TN, chlorophyll concentration (Chl-ab), proline; plant height, diameter, and volume of timber; and soil urease activity, STN, and available N (Avail N) concentrations in the long term (month 6, M6). Redundancy analysis showed that soil available phosphorus was significantly positively correlated with plant growth in M3, and soil Avail N was negatively correlated with plant growth in M6. In M3, soil catalase was more closely correlated with plant parameters than other enzyme activities and soil nutrients, and in M6, soil urease, polyphenol oxidase, and peroxidase were more closely correlated with plant parameters than other environmental factors and soil enzyme activities. PCA results showed that soil enzyme activities were significantly improved under all treatments relative to the control. Hence, photosynthesis, plant growth, and soil N retention were positively affected by bacterial fertilizer in M6, and bacterial fertilizer applications had positive and significant influence on soil enzyme activities during the trial period. Thus, bacterial fertilizer is attractive for use as an environmentally friendly fertilizer in Eucalyptus plantations following proper field evaluation.

Cell wall modification is integral to many plant developmental processes where cells need to separate, such as abscission. However, changes in cell wall composition during natural fruit abscission are poorly understood. In olive (Olea europaea L.), some cultivars such as ‘Picual’ undergo massive natural fruit abscission after fruit ripening. This study investigates the differences in cell wall polysaccharide composition and the localization of pectins and arabinogalactan protein (AGP) in the abscission zone (AZ) during cell separation to understand fruit abscission control in ‘Picual’ olive. To this end, immunogold labeling employing a suite of monoclonal antibodies to cell wall components (JIM13, LM5, LM6, LM19 and LM20) was investigated in olive fruit AZ. Cell wall polysaccharide extraction revealed that the AZ cell separation is related to the de-esterification and degradation of pectic polysaccharides. Moreover, ultrastructural localization showed that both esterified and unesterified homogalacturonans (HGs) localize mainly in the AZ cell walls, including the middle lamella and tricellular junction zones. Our results indicate that unesterified HGs are likely to contribute to cell separation in the olive fruit AZ. Similarly, immunogold labeling demonstrated a decrease in both galactose-rich and arabinose-rich pectins in AZ cell walls during ripe fruit abscission. In addition, AGPs were localized in the cell wall, plasma membrane and cytoplasm of AZ cells with lower levels of AGPs during ripe fruit abscission. This detailed temporal profile of the cell wall polysaccharide composition, and the pectins and AGP immunolocalization in the olive fruit AZ, offers new insights into cell wall remodeling during ripe fruit abscission.

High-amylose maize starch (AS) was modified by graft copolymerization with sodium acid maleate and disodium maleate, using the KMnO-NaHSO redox system, and covalently crosslinked with N,N'-bismethylene acrylamide in inverse suspension polymerization process. The resulting modified starches were evaluated as absorbent materials for release fertilizers. Firstly, AS was obtained by leaching from native maize starch and posterior precipitation in ethanol. The gelatinized AS, comonomers, redox pair and crosslinker were dissolved in distilled water, which was used as dispersed phase; while paraffin oil was used as the continuous phase and sorbitan esters as stabilizers. In the reacions, parameters such as the AS amount of 10 wt%/v with respect to the dispersed phase; the degree of neutralization of maleic acid of 80%; the ratio [NaHSO]/[KMnO] of 2.6; the ratio between crosslinker and comonomers of 8.9 × 10; the stirring speed of 250 rpm; the reaction temperature at 60 °C; and a reaction time of 3 h, were kept constant. All the resulting amylose modified starches were characterized by potenciometric titration, X-ray diffraction and scanning electronic microscopy. The absorption capacity of these materials was studied by analyzing their swelling in various media and different pHs. Finally, the amylose modified starches were evaluated as systems for release fertilizers by measuring the loaded and released amount of fertilizer by gravimetry and conductimetry, respectively., This work was funded by the MICINN (PID2019-104600RB-I00), the Agencia Estatal de Investigación (AEI, Spain) and Fondo Europeo de Desarrollo Regional (FEDER, EU).

The formation of supramolecular complexes between C60 and a molecular nanographene endowed with both positive and negative curvatures is described. The presence of a corannulene moiety and the saddle shape of the molecular nanographene allows the formation of complexes with 1:1, 1:2, and 2:1 stoichiometries. The association constants for the three possible supramolecular complexes were determined by 1H NMR titration. Furthermore, the stability of the three complexes was calculated by theoretical methods that also predict the photoinduced electron transfer from the curved nanographene to the electron acceptor C60. Time-resolved transient absorption measurements on the ns-time scale showed that the addition of C60 to NG-1 solutions and photo-exciting them at 460 nm leads to the solvent-dependent formation of new species, in particular the formation of the one-electron reduced form of C60 in benzonitrile was observed Ministerio de Ciencia, Innovación y Universidades. Grant Numbers: CTQ2017-83531-R, RED2018-102815-T, CTQ2017-85341-P, PID2020-113711GB-I00, CTQ2017-84327-P, IJC2019-039846-I Consell Català de Recerca i Innovació. Grant Number: 2017SGR39

Succinylated bitter cassava starches are evaluated for the removal of cationic, methylene blue (MB) and anionic, methyl orange (MO) dyes present in water. The native starch (NS) extracted from bitter cassava by the dry method, is modified using succinic anhydride (SA) as esterifying agent and sodium hydroxide, sodium carbonate, sodium sulfate, and sodium chloride as non-toxic and environmentally friendly catalysts. The effect of the type and concentration of catalyst on the modification is evaluated. Starch replacement with SA is confirmed by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The degree of substitution in the resulting succinylated starches is determined by volumetric analysis, presenting high values (0.5–0.9). These materials act as superabsorbent gels, sensitive to changes in pH and ionic strength, and mostly with anti-polyelectrolytic behavior. MB dye has a higher affinity for succinylated starches than the MO dye. The removal capacity of MB is also influenced by the pH and the ionic strength of the solution. The kinetics and adsorption isotherms are satisfactorily adjusted to the pseudo-second order and Freundlich models, respectively. The esters functionalities of the starch prove to be reusable adsorbents, completing successfully five cycles of adsorption-desorption., This research was funded by MINECO, Project MAT2016-78437-R, the Agencia Estatal de Investigación (AEI, Spain), and Fondo Europeo de Desarrollo Regional (FEDER, EU) and the Universidad del Zulia, CONDES-LUZ.

Membranes are mainly composed of a lipid bilayer and proteins, constituting a checkpoint for the entry and passage of signals and other molecules. Their composition can be modulated by diet, pathophysiological processes, and nutritional/pharmaceutical interventions. In addition to their use as an energy source, lipids have important structural and functional roles, e.g., fatty acyl moieties in phospholipids have distinct impacts on human health depending on their saturation, carbon length, and isometry. These and other membrane lipids have quite specific effects on the lipid bilayer structure, which regulates the interaction with signaling proteins. Alterations to lipids have been associated with important diseases, and, consequently, normalization of these alterations or regulatory interventions that control membrane lipid composition have therapeutic potential. This approach, termed membrane lipid therapy or membrane lipid replacement, has emerged as a novel technology platform for nutraceutical interventions and drug discovery. Several clinical trials and therapeutic products have validated this technology based on the understanding of membrane structure and function. The present review analyzes the molecular basis of this innovative approach, describing how membrane lipid composition and structure affects protein-lipid interactions, cell signaling, disease, and therapy (e.g., fatigue and cardiovascular, neurodegenerative, tumor, infectious diseases).

The Salt-Overly-Sensitive (SOS) pathway controls the net uptake of sodium by roots and the xylematic transfer to shoots in vascular plants. SOS3/CBL4 is a core component of the SOS pathway that senses calcium signaling of salinity stress to activate and recruit the protein kinase SOS2/CIPK24 to the plasma membrane to trigger sodium efflux by the Na/H exchanger SOS1/NHX7. However, despite the well-established function of SOS3 at the plasma membrane, SOS3 displays a nucleo-cytoplasmic distribution whose physiological meaning is not understood. Here, we show that the N-terminal part of SOS3 encodes structural information for dual acylation with myristic and palmitic fatty acids, each of which commands a different location and function of SOS3. N-myristoylation at glycine-2 is essential for plasma membrane association and recruiting SOS2 to activate SOS1, whereas S-acylation at cysteine-3 redirects SOS3 toward the nucleus. Moreover, a poly-lysine track in positions 7–11 that is unique to SOS3 among other Arabidopsis CBLs appears to be essential for the correct positioning of the SOS2-SOS3 complex at the plasma membrane for the activation of SOS1. The nuclear-localized SOS3 protein had limited bearing on the salt tolerance of Arabidopsis. These results are evidence of a novel S-acylation dependent nuclear trafficking mechanism that contrasts with alternative subcellular targeting of other CBLs by S-acylation

The clinical characteristics of patients with postoperative hypoparathyroidism who recover parathyroid function more than 12 months after surgery have not been studied. We aimed to evaluate whether the intensity of replacement therapy with calcium and calcitriol is related to the late recovery of parathyroid function. We compared the demographic, surgical, pathological, and analytical features of two groups of patients: cases, i. e., late recovery patients (those who recover parathyroid function>1 year after thyroidectomy, n=40), and controls, i. e., patients with permanent hypoparathyroidism (n=260). Replacement therapy with calcium and calcitriol was evaluated at discharge of surgery, 3–6 months, 12 months, and last visit. No significant differences were found in clinical, surgical, pathological, or analytical characteristics between cases and controls. The proportion of cases who required treatment with calcium plus calcitriol at 12 months was significantly lower than that found in controls (p

To determine the influence of different doses of maximal acute exercise on the kinetics of plasma homocysteine (tHcy) and its relationship with oxidative status and vascular function, nine recreational runners completed a 10 km race (10K) and a marathon (M). Blood samples were collected before (Basal), immediately post-exercise (Post0), and after 24 h (Post24). Nutritional intake was controlled at each sample point. A significant increase in tHcy was observed after both races, higher after M. Basal levels were recovered at Post24 after 10K, but remained elevated at Post 24 for M. A significant decrease in GSH/GSSG ratio was observed in Post0, especially marked after M. Furthermore, this increase in pro-oxidant status remained at Post24 only after M. Other oxidative status markers failed to confirm this exercise-induced pro-oxidant status except glutathione peroxidase activity that was lower in Post24 compared to Basal in 10K and in Post0 and Post24 in M. No statistical correlation was found between oxidative markers and tHcy. No significant changes were observed in the concentration of endothelial cell adhesion molecules (VCAM-1 and E-Selectin) and VEGF. In conclusion, tHcy increases in an exercise–dose–response fashion but is not related to endothelial dysfunction mediated by oxidative stress mechanisms.

In this work versatile boron–carbon nitride composite materials were synthesized and utilized in a sustainable process using sunlight as the energy source for the continuous-flow selective photocatalytic production of acetone from 2-propanol. It is worth highlighting that the sample preparation was carried out by an environmentally friendly strategy, without a solvent or additional reagents. Samples containing boron in 1–10 wt% were subjected to physico-chemical characterization using XRD, porosimetry, UVvisible spectroscopy, TEM, energy-dispersive X-ray spectroscopy and XPS. The reaction output was analyzed on the basis of the reaction rate, selectivity and quantum efficiency of the process. A correlation analysis between catalytic properties with two observables, the boron phase distribution in the materials and charge handling efficiency (measured using photoluminescence), rationalizes photoactivity. Such an analysis indicates that the presence of an amorphous boron metallic phase and its contact with the carbon nitride component are key to setting up a renewable and easily scalable chemical process to obtain acetone., MINECO (Spain) ENE2016-77798-C4-1-R, Consejo Superior de Investigaciones Cientificas (CSIC), Secretaria de Ciencia Tecnologia e Innovacion of CDMX (SECTEI, Mexico), MINECO CTQ2016-78289-P, European Union (EU), RUDN University Program 5-100

The decomposition of formic acid to obtain hydrogen has been studied using molybdenum carbides supported on activated carbon and two high surface area graphites, H-200 (200 m(2) g(-1)) and H400 (400 m(2) g(-1)). Particular attention is paid to the effect of Mo loading. The catalysts were prepared in situ using a mixture of CH4 and H-2 at a temperature of up to 700 degrees C. Under these conditions, carburization was mostly complete. We observed that the support influenced the MoxC phase obtained so that it seems that the ratio of defective carbon influences the phase. However, for these materials the C/Mo ratio did not influence the obtained crystal phase. Characterization by XRD showed that while the beta-Mo2C phase was obtained over activated carbon and over H-200, in contrast, MoOxCy was obtained over H400. These catalysts reached 100% conversion on formic acid decomposition at temperatures in the range of 190-250 degrees C and were also highly selective under these mild conditions, with values for CO2 selectivity in the range of 85.096.5%. The best results were achieved over a 10 wt% Mo loading on activated carbon that reached 96.5% selectivity to H-2. Also, changes in the molybdenum phases were observed on the spent catalyst. Some redox transformations during reaction were responsible for the transformation of beta-Mo2C into oxycarbide MoOxCy. In summary, the results of the catalytic performance indicated that the beta-Mo2C phase was more active, selective and stable than MoOxCy under the studied conditions.

In this study, we analyzed the photocatalytic degradation of toluene using composite systems consisting of a tungsten oxide component supported on a pure anatase phase. To scrutinize the photocatalytic process, herein we presented a new method with combined spectroscopic and kinetic tools to provide novel and quantitative information mostly obtained in situ under reaction conditions. First, it allows us to extract information quantitatively, regarding charge recombination and the fraction of kinetically relevant charge species reaching the surface of the material and used in chemical steps. In addition, the method allows us to detail how efficiently such kinetically relevant charge carrier species interact with key reactant and intermediate molecules. The application of such procedure to the elimination of toluene shows how the composite system improves the activity with respect to the relevant pure-anatase reference catalyst. This appears to be a complex phenomenon, with implication in several elemental steps of the reaction. The new method can be easily generalized to any photocatalytic reaction and would pave the way to progress in the quantitative understanding of the photocatalytic process.

PGPR is widely used to improve the capacity of soil nutrient retention, which is closely related to soil microbial activity and enzyme activity. Biochar amendment can alter soil physicochemical properties, such as soil pH and the capacity of water holding. We conducted a study in Guangxi, China, in January 2018 to determine the responses of soil nutrient concentrations and enzyme activities to PGPR and biochar applications in a eucalyptus plantation. Bacillus megatherian strain Du07 was isolated from eucalyptus rhizosphere soil and was confirmed to be a PGPR by partial 16S rDNA sequencing. Biochar applied in our study was made from wheat straw and was used at three application levels (0 t.hm−2, 20.0 t hm−2, 40 t.hm−2). The following treatments were evaluated: (1) no PGPR and no biochar applied (M0B0), (2) 5 × 1010 cfu/mL PGPR (MB0), (3) 20.0 t.hm−2 biochar (B20), (4) 5 × 1010 cfu/mL PGPR plus 20.0 t.hm−2 biochar (MB20), (5) 5 × 1010 cfu/mL PGPR plus 40.0 t.hm−2 biochar (MB40). In general, separate application of PGPR and biochar may increase soil urease activity, total nitrogen (TN), and total potassium (TK) concentrations, and co-application of PGPR and biochar may increase soil sucrase activity, electrical conductivity (EC), and TK concentration, indicating that the manner of biochar and PGPR application had a significant influence on soil physicochemical properties and enzyme activities except for TK concentration. Redundancy analysis (RDA) showed that soil NO3−-N, NH4+-N, TK, TP, and SWC were more closely related to soil enzyme activities than other soil physicochemical properties under our experimental conditions.

The development of inherent antimicrobial polymeric fibers can contribute to overcoming the increasing problem of infectious diseases and multiresistant microorganisms. Here, we propose the preparation of poly(lactic acid) (PLA) based electrospun fibers blended with poly[2-(4-methylthiazol-5-yl)ethyl methacrylate] (PMTA), which quaternized have proven broad spectrum antimicrobial activity either in solution or solid state. We have demonstrated that quaternized PLA/PMTA fiber mats have a remarkable antibacterial activity against S. aureus. As determined by scanning electron microscopy and Raman spectroscopy, quaternized PMTA segregates toward the outmost surface of PLA/PMTA fiber leaving the thiazolium group widely available onto the fiber surfaces, facilitating the bacteria killing by contact mode., This work was funded by MAT2017-88123-P and MAT2016- 78437-R (FEDER−EU). C.E. also acknowledges IJCI-2015- 26432 contract from MINEICO. The authors also acknowledge Dr. Leoncio Garrido for the feedback in the electrospinning.

Herein, hydrogels based on starch from corn, sweet cassava and bitter cassava were prepared by a straightforward approach. The hydrogels were obtained by an oxidation process using the redox system KMnO/NaHSO which leads to the formation of carbonyl and carboxyl groups with minimum polymer hydrolysis. The resulting oxidized samples as well as the native starches were extensively characterized by scanning electron microscopy, thermogravimetric analysis and wide angle X-ray scattering, among others. High gel fraction values and low degree of crystallinity were obtained in all the cases, which values vary slightly depending on the botanical source. High swelling capacity was observed for all the samples, which behave as hydrogels. The influence of the ionic strength and pH in the swelling capacity of the oxidized starches was also studied. The samples exhibit an anti-polyelectrolyte behavior and the water uptake increases at basic pH as the carboxylic groups become ionized. The hydrogels were also loaded with urea, potassium nitrate and ammonium sulfate as model fertilizers and their potential for controlled release was investigated., Authors want to acknowledge the Universidad del Zulia for the financial support, in particular CONDES-LUZ and also the MINECO (Project MAT2016-78437-R and Project MAT2017-86450-C4-1-R), the Agencia Estatal de Investigación (AEI, Spain) and Fondo Europeo de Desarrollo Regional (FEDER, EU).

Background Due to the increased use of engineered nanoparticles (NPs), their tracing in environmental and biological systems is of utmost importance. Besides their accumulation within a biological specimen, little is known about their degradation and transformation into corresponding low-molecular species that might influence any toxicological impact. Analytical methods Wistar rats underwent intraperitoneal injections of 40 nm citrate-stabilized gold nanoparticles. Different liver samples were analysed for the occurrence of nanoparticles and potential degradation products by means of spICP-MS, TEM and HPLC-ICP-MS. Main findings Studies using spICP-MS revealed the presence of the originally administrated Au NPs (40 nm diameter) and some evidences of other Au-containing species due to the increased background signal. Images obtained by transmission electron microscopy (TEM) showed the predominant presence of particles of significantly smaller diameter (6 ± 2 nm). As complementary method, HPLC-ICP-MS confirmed the presence of both particle types indicating a degradation of the Au NPs accompanied by detection of low-molecular Au species. Conclusions This study underlines that degradation of gold nanoparticles to low-molecular gold species might have to be taken into account in future for studies on their toxicological behaviour and their potential use in clinical applications.