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Eicosapentaenoic acid (EPA) from freeze-dried biomass of Nannochloropsis oceanica microalgae resists ruminal biohydrogenation in vitro, but in vivo demonstration is needed. Therefore, the present study was designed to test the rumen protective effects of N. oceanica in lambs. Twenty-eight lambs were assigned to one of four diets: Control (C); and C diets supplemented with: 1.2% Nannochloropsis sp. oil (O); 12.3% spray-dried N. oceanica (SD); or 9.2% N. oceanica (FD), to achieve 3 g EPA /kg dry matter. Lambs were slaughtered after 3 weeks and digestive contents and ruminal wall samples were collected. EPA concentration in the rumen of lambs fed FD was about 50% higher than lambs fed SD or O diets. Nevertheless, the high levels of EPA in cecum and faeces of animals fed N. oceanica biomass, independently of the drying method, suggests that EPA was not completely released and absorbed in the small intestine. Furthermore, supplementation with EPA sources also affected the ruminal biohydrogenation of C18 fatty acids, mitigating the shift from the t10 biohydrogenation pathways to the t11 pathways compared to the Control diet. Overall, our results demonstrate that FD N. oceanica biomass is a natural rumen-protected source of EPA to ruminants.

WC-Ni nanoparticles were synthesized using the gas-solid reaction method in a fixed-bed reactor. The studied parameters were the influence of the synthesis temperatures (800 °C, 850 °C and 900 °C), the reaction time (90 min, 120 min, and 150 min) and the nickel concentration (5 wt%Ni, 10 wt%Ni and 15 wt%Ni) on the average crystallite size by means of a 2³ factorial experimental design based on the results obtained by XRD. These powders had their chemical and morphological characteristics evaluated using XRD, BET, SEM and EDS analyzes. The XRD analysis results show that the method was effective in obtaining WC-Ni nanostructured composite powders with good particle dispersion, desired purity, mean crystallite size ranging from 24.2 nm to 38 nm, and surface area ranging from 24.6 m2/g to 46.7 m2/g. The statistical analysis showed that the synthesis temperature variable had the greatest influence on the increase in crystallite size. Furthermore, the combination of temperature and isotherm also has a relevant effect on the response variable (crystallite size).

Among the several obstacles which impede efficiency enhancement of CZTS solar cells, the sub-optimized Mo back contact and the unfavorable conduction band offset at CZTS/CdS interface are the critical ones, contributing largely to high surface recombination and low open circuit voltage. In this article, a numerical simulation model was used for device structure analysis and performance optimization. A substrate configuration of CZTS solar cell was considered. Benchmarking study of the reference cell gives a conversion efficiency of 8.3% which matches well with the reported experimental value, validating the accuracy of our simulation model. Thereafter, we have implemented several modifications in the experimental device structure including an alternative back contact, a back surface passivation layer, a Cd-free buffer layer with tunable conduction band minimum, and a wide band gap ZnO-based alloy material which enhances the spectral response to shorter wavelength contributing to higher efficiency. A systematic optimization of device structure results in the increase of JSC and VOC due to the increment in diffusion length and optimal free carrier collection which ultimately increases the power efficiency from 8.4 to 20.6%.

Recently, consumption of collagen-based foodstuffs has grown significantly, especially collagen hydrolysate, used as a dietary supplement. Information available on the content of essential and toxic elements in these products, however, is incipient. This study provides a novel assessment of the mineral profile (Al, As, Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, P, S, V, and Zn) of collagen hydrolysate and gelatin by inductively coupled plasma optical emission spectrometry (ICP OES) and mass spectrometry (ICP-MS). Thirty-two samples were digested with diluted HNO3 and H2O2, using an efficient microwave-assisted decomposition method (11.9% residual carbon content). The methodology was validated using certified reference materials and recovery tests, with agreement between the determined and certified/added concentration values (85–124%), and relative standard deviation of up to 18%. The limits of quantification ranged from 0.33 μg kg−1 (Cd) to 24 mg kg−1 (Na). The contributions of collagen hydrolysate to the Dietary Reference Intake values of the evaluated minerals were low, with the highest value being 13.5% for the Adequate Intake of Cr. The findings of Permitted Daily Exposure suggest that there is no risk of contamination with As and Cd by consuming this food supplement. Concentrations of Cr, Mn, and Zn reported on product labels agreed with experimental results. For Na, these values differed, indicating that a more rigorous quality control of collagen hydrolysate is necessary, in view of the health problems caused by excessive consumption of this element.

ZrO2–SiO2 mixed oxides were obtained by two different methods. The influence of microwave-assisted hydrothermal treatment and the differences of two different synthesis methods were investigated. The obtained materials were characterized by DSC, XRD, SEM and FTIR spectrometry. The N2 adsorption analysis data (BET and BJH) was used for the determination of textural properties of the mixed oxides. The two synthesis methods point out differences in the way Zr is incorporated in the silica matrix. The microwave heating was responsible to change the textural properties but not the crystallinity. Finally, the catalytic activity was tested in the transesterification of soybean oil and esterification of oleic acid, both with methanol. The reaction conversions were measured by H-NMR. None of the samples presented catalytic activity in the transesterification of soy oil with methanol. However, the oleic acid was esterified with methanol at subcritical conditions.

Polycyclic aromatic hydrocarbons (PAHs) are a family of organic compounds comprising two or more fused aromatic rings which feature manifold applications in modern technology. Among these species, those presenting an open-shell magnetic ground state are of particular interest for organic electronic, spintronic, and non-linear optics and energy storage devices. Within PAHs, special attention has been devoted in recent years to the synthesis and study of the acene and fused acene (periacene) families, steered by their decreasing HOMO-LUMO gap with length and predicted open-shell character above some size. However, an experimental fingerprint of such magnetic ground state has remained elusive. Here, we report on the in-depth electronic characterization of isolated peripentacene molecules on a Au(111) surface. Scanning tunnelling spectroscopy, complemented by computational investigations, reveals an antiferromagnetic singlet ground state, characterized by singlet-triplet inelastic excitations with an experimental effective exchange coupling (Jeff) of 40.5 meV. Our results deepen the fundamental understanding of organic compounds with magnetic ground states, featuring perspectives in carbon-based spintronic devices.

Ascorbic acid, commonly known as vitamin C, is a weak acid and natural antioxidant that plays essential biological roles in the participation of collagen formation and the absorption of iron by the body. The objective of this work was to verify, through molecular modeling, partial loads and evaluation of PRM reactivity parameters, that it presents favorable electronic densities in stereochemically located positions, for the formation of metallic salts, associated with supposed complex systems. Its electrolytic properties showed a type 1: 1 behavior in freshly prepared aqueous millimolar solution. This is in agreement with the values of pH, Ka1 and Ka2 respectively, evaluated for an equilibrium situation through the program RAÍZES 1.0, developed by the authors. Thermal decomposition starts around 180-190oC and continues until reaching a temperature of 570.3 °C, in which a small experimental percentage of waste has been associated with the presence of reduced carbon. The absorption spectrum in the infrared region identified the main transitions attributed to C = O, C = C, OH, present in their functional groups. The UV-Vis absorption spectrum showed an intense band that occurs between 207 - 312 nm, with maximum absorption peak, Amax = 3,6123 at 249, and 250 nm. This band presents itself in the region where the n → π*, n → σ* and π → π* transitions occur associated with the chromophore groups. The strength of the oscillator f is comparable to those presented by chromophore groups that have intense molecular transitions, in which some types of molecules are used as dyes and other analogs used as sensitizers in solar photocells or devices emitting electromagnetic radiation.

The critical value of soil exchangeable potassium (K) (mg K kg−1) is a valuable tool for an efficient K fertilization management in potato production systems. The aim of the present study was to determine the critical value of soil exchangeable K for potato crops grown in different environments and differing availabilities of initial exchangeable K. The data used in this study were taken from 34 experiments on K fertilization conducted in southern Chile from 1977 to 2017 by the National Potato Center at the Instituto de Investigaciones Agropecuarias (INIA). Yield responses to K fertilization rates were assessed with linear-plateau and Mitscherlich models in order to determine the critical soil exchangeable K across environments. Across experiments, the average fresh tuber yield ranged between 18 and 91 Mg ha−1. Fresh tuber yields decreased by up to 70% when no K fertilization was applied. Yield reduction was concentrated around 25% in response to K deficiency. Relative yields were described as significant by both linear-plateau and Mitscherlich models. However, relative yields were better described by the linear-plateau model (p

In this work, molecular models were obtained, and the reactivity parameters of ε-caprolactam and ophenanthroline were calculated to evaluate the interaction in the formation of complex molecular compounds. It was observed that the main electron donor atoms, in the formation of the metal-ligand bond, are centered mainly on the oxygen and nitrogen atoms, respectively, which are sterically more favorable in these species. Conductance measurements in an aqueous solution were obtained to observe the electrolytic behavior of these compounds. Infrared spectra were also recorded to characterize vibrational transitions in identifying these species when present in complex systems. Molecular spectra of absorption in the UV-visible region were recorded to evaluate the spectrochemical properties of these individual ligands and further verify their influence on the formation of complex molecular systems. The parameters evaluated include the molar absorptivity ε, integrated absorption coefficient, oscillator force, and transition dipole moment. It was observed that the ε parameter indicates molecular transitions in the 190 – 300 nm region and the near-infrared, and the oscillator strength is typical of molecules used as dyes and sensitizers for optical light-emitting systems or light-to-electricity converters.

In order to identify risk factors for SARS-CoV-2 infection as well as for severe/critical COVID-19 in rheumatic and musculoskeletal diseases (RMDs) patients, we conducted a multicentre observational nationwide study of adult patients prospectively-followed in the Rheumatic Diseases Portuguese Register – Reuma.pt – during the first 6 months of the pandemic. We further evaluated the development of IgG antibodies against the receptor-binding domain (RBD) of SARS-CoV-2 in patients with RMDs. We used multivariate logistic regression to compare patients with COVID-19 (COVID-19+) with those who did not develop the disease (COVID-19-) and patients with mild/moderate disease with those exhibiting severe/critical COVID-19. COVID-19+ patients were asked to collect a blood sample for IgG testing ≥ 3 months after infection and results were compared with age-, sex- and sampling date-matched controls. Overall, 179 cases of COVID-19 were registered in Reuma.pt in the period of interest (median age 55 (IQR 20); 76.5% females) in a total of 6404 registered appointments. We found that patients treated with TNF inhibitors had reduced odds of infection (OR=0.16, 95%CI 0.10-0.26, p

A Glibenclamida é um hipoglicemiante oral de segunda geração da classe das sulfoniluréias, usado para o tratamento do diabetes mellitus tipo 2 (NERY et al. 2007). O presente estudo teve como objetivo realizar o controle de qualidade físico-químico dos comprimidos similar e referência de Glibenclamida 5mg. O estudo Caracteriza-se por um estudo comparativo, analítico, e de abordagem qualitativa onde foi analisado o peso médio, friabilidade, dureza e desintegração, de comprimido Similar e de Referência. Não houve quaisquer desvio de qualidade aos testes submetidos com o comprimido.

On-surface synthesis has recently become an essential approach toward the formation of carbon-based nanostructures. Special emphasis is set on the synthesis of π-conjugated polymers taking into consideration their relevance and potential in organic electronics, optoelectronics and spintronics. Here, we report the on-surface synthesis of conjugated ladder polymers consisting of pentacene units doubly-linked via ethynylene-like bonds on the Au(111) surface under ultra-high vacuum conditions. To this aim, we have sublimed pentacene-like precursors equipped with four :CBr2 functional groups to steer the desired reaction upon annealing on the surface. The atomically precise structure of the obtained polymers has been unambiguously characterized via low-temperature scanning tunneling microscopy and non-contact atomic force microscopy. In addition, scanning tunneling spectroscopy complemented with density-functional theory calculations reveal the narrow bandgap of the polymer. Our results provide potential for the synthesis of π-conjugated polymers with prospects in functional carbon-based nanomaterials that exploit multiple connections between molecular backbones.

In this work, the production and characterization of pellets made from rice husks and wheat straws is presented. For this, physicochemical and energetic characterization of pellets produced with rice husks and mixtures of rice husks with wheat straws were carried out, followed by a comparison with those properties stablished by the ISO 17225-6 standard. The rice husk pellets exhibited the lowest calorific value (3090.64–4049.05 kcal/g) and highest ash content (12.81–17.51%), while the pellets made from mixtures obtained the highest calorific power (4301.10–4573.50 kcal/g) and a reduced amount of ashes (11.43–13.06%). Moreover, the pellets produced with both biomasses exceed the moisture, ashes and nitrogen content, but complied with diameter, length and durability components. These results suggest that these biomasses blends improve the quality and combustion characteristics of the pellets, aiming to enhance the research for the manufacturing of these sustainable biofuels.

Herein, we report the synthesis of nontoxic pyrite iron sulfide (FeS2) nanocrystals (NCs) using a two-pot method. Moreover, we study the influence of these NCs incorporated into the PTB7:PC71BM active layer of bulk-heterojunction ternary organic photovoltaic (OPV) cells. The OPV devices are fabricated with the direct configuration glass/ITO/PEDOT:PSS/PTB7:PC71BM:FeS2/PFN/FM. The Field’s metal (FM) is a eutectic alloy composed of 32.5% Bi, 51% In and 16.5% Sn by weight that melts at 62 °C. It is deposited on the active layer/PFN under atmospheric conditions. Ternary active layers are prepared by adding small amounts of the semiconducting FeS2 NCs at different weight ratios of 0.0, 0.25, 0.5, and 1.0 wt % with respect to the electron donor PTB7. With respect to the reference device (without FeS2), a 21% increase in the power conversion efficiency (PCE) is observed for OPVs with 0.5 wt % FeS2, such that the PCE of the OPVs is enhanced from 5.69 to 6.47%. According to the Kruskal–Wallis and Mann–Whitney statistical tests, all OPV devices follow the same trend.

Nanoparticles of titanium dioxide (TiO2), synthesized by the sonochemical technique, were mixed with different amounts of graphene oxide (GO), obtained by the improved method of Hummer, in order to modify their bandwidth. The TiO2/OG compounds were characterized using different techniques: X-ray Diffraction (XRD), transmission electron microscopy (TEM), Raman and UV-Vis-NIR spectroscopy. TiO2 bandgap decreased, with GO incorporation, from 3.2 to 2.72 eV when GO was present at 20 weigh percentage (TiO2/GO-20%). Photodegradation experiments of methylene blue (MB) were performed with the materials to verify their photocatalytic activity. At 40 minutes, the pure TiO2 degraded 48% of MB, whereas the compound TiO2/GO-20% degraded 88%, showing a good incorporation of both compounds and the improvement of TiO2 photocatalitic properties.

Cistus ladanifer L. is a shrub present in Mediterranean areas without major use, but which can be incorporated into ruminant diets, improving the digestive efficiency of dietary protein and product quality. The high levels of plant secondary metabolites, including condensed tannins, may be responsible for the beneficial properties of the plant, but can also reduce palatability. In this study, C. ladanifer was incorporated into lambs’ diets, either as aerial parts or as a condensed tannin extract, reaching 1.25% and 2.5% of condensed tannins of dry matter. Saliva was collected and electrophoretic profiles of both whole saliva and saliva after in vitro incubation with C. ladanifer tannins were compared. Animals receiving the aerial parts of C. ladanifer decreased feed ingestion. Differences in salivary protein profiles were observed for animals fed with the higher levels of aerial parts of the plant (CL2.5 group). Most of the lambs’ salivary proteins were present in the precipitate formed after tannin-saliva incubation, and one of the bands increased in CL2.5 group was present in high proportion in the precipitate. None of the protein bands stained pink with Coomassie Brilliant Blue, suggesting the absence, or low amounts, of proline-rich proteins in lamb saliva. The results suggest that the aerial parts of C. ladanifer are poor in palatability and that salivary proteins from lambs, due to their affinity for this plant’s secondary metabolites, can contribute to this. Further protein identification is needed, as well as studies to access the stability of the tannin-protein complexes through the gastrointestinal tract.

CdS/CdTe heterostructures were fabricated by chemical techniques. CdS films were deposited by chemical bath deposition on soda-lime/SnO2:F substrates. CdS films were obtained varying the concentration of thiourea and the growth temperature. CdTe films were grown by electrodeposition on SnO2:F/CdS substrates at 80°C, using ethylenediaminetetraacetic acid (EDTA) as strong complexing agent. The cathodic potential was varied from − 0.70 V to − 1.20 V. Raman spectroscopy showed that for a potential of − 1.20 V a CdTe film with high crystalline quality was obtained. The electric characterization through J–V measurements, indicates the formation of a n-CdS/p-CdTe junction. These results showed that p-type CdTe films grown by electrodeposition technique using EDTA as strong complexing agent were obtained.

Engineering low-band-gap -conjugated polymers is a growing area in basic and applied research. The main synthetic challenge lies in the solubility of the starting materials, which precludes advancements in the field. Here, we report an on-surface synthesis protocol to overcome such difficulties and produce poly(p-anthracene ethynylene) molecular wires on Au(111). To this aim, a quinoid anthracene precursor with =CBr2 moieties is deposited and annealed to 400K, resulting in anthracene-based polymers. High-resolution nc-AFM measurements confirm the nature of the ethynylene-bridge bond between the anthracene moieties. Theoretical simulations illustrate the mechanism of the chemical reaction, highlighting three major steps: dehalogenation, diffusion of surface-stabilized carbenes, and homocoupling, which enables the formation of an ethynylene bridge. Our results introduce a novel chemical protocol to design -conjugated polymers based on oligoacene precursors and pave new avenues for advancing the emerging field of on-surface synthesis. Funding Agencies|Comunidad de Madrid [Y2018/NMT-4783, S2013/MIT-3007, S2018/NMT]; European Research Council [ERC-320441-Chirallcarbon, ERC-766555-ELECNANO]; Spanish Ramon y Cajal programme [RYC-2012-11133]; MINECO of Spain [FIS 2015-67287-P, CTQ2017-83531-R, CTQ2016-81911-REDT]; Severo Ochoa Programme for Centers of Excellence in RD (MINECO) [SEV-2016-0686]; Praemium Academie of the Academy of Science of the Czech Republic [MEYS LM2015087, GACR 18-09914S]; Operational Programme Research, Development, and Education - European Structural and Investment Funds; Czech Ministry of Education, Youth, and Sports [CZ.02.1.01/0.0/0.0/16019/0000754]; Czech Science Foundation [19-27454X]; Swedish Research Council [642-2013-2080]; Swedish Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

Facile, low-temperature synthesis of kesterite CZTS nanocrystals (NCs) using single solvent by heating up approach is presented for the first time. Temperature and time dependence on the structural, morphological and compositional properties are investigated in detail. The size of the NCs was found to increase from 15 to 45 nm with increases in the reaction temperature. From the structural analysis, secondary and ternary phases were detected at less reaction time, and pure phase of CZTS was obtained at 3 h. On the basis of the detailed time-dependent phase evolution, a plausible formation mechanism of CZTS NCs was proposed. The sequence of CZTS phase evolved from Cu2S phase to Cu2SnS3 intermediate compound and finally to pure kesterite CZTS. The optimal composition of Cu/(Zn + Sn) and Zn/Sn ratio was obtained at 3 h. The calculated band gap was found to be 1.5 eV which is an optimum value for solar cell applications. Thus, the results revealed that the reaction temperature and time played a determining role to obtain pure phase CZTS with controlled composition and optimum band gap.

Background Staphylococcus lugdunensis is a commensal skin microorganism that, unlike other coagulase-negative staphylococci, presents increasing clinical importance. This species yields a metalloprotease called lugdulysin that may contribute to its higher degree of virulence. This study aimed to determine the biochemical characterization of the lugdulysin produced by S. lugdunensis clinical isolates and investigate its effect on the formation and disruption of biofilm of Staphylococcus aureus isolates. The protease was isolated and characterized for its optimal pH and temperature, activity in the presence of inhibitors and enzymatic kinetics. The influence of metal cofactor supplementation on proteolysis was also evaluated, with and without inhibitors. Finally, the protease capacity to inhibit and disrupt biofilms of different S. aureus lineages and biofilm matrix was analyzed. Results The protease optimal pH and temperature were 7.0 and 37° C, respectively. EDTA inhibited the protease, and the activity was not recovered by divalent ion supplementation. In addition, divalent ions did not change enzymatic activity without inhibitors, which was stable for up to 3 hours. Its structure was determined via homology modelling. The protease significantly inhibited the formation and disrupted established biofilms of S. aureus isolates with protein biofilm. Conclusions This study confirmed features of the lugdulysin metalloprotease and showed that this S. lugdunensis virulence factor may be a new competition mechanism and/or modulation of the staphylococcal biofilm.

The design of organometallic complexes is at the heart of modern organic chemistry and catalysis. Recently, on-surface synthesis has emerged as a disruptive paradigm to design previously precluded compounds and nanomaterials. Despite these advances, the field of organometallic chemistry on surfaces is still at its infancy. Here, we introduce a protocol to activate the inner diacetylene moieties of a molecular precursor by copper surface adatoms affording the formation of unprecedented organocopper metallacycles on Cu(111). The chemical structure of the resulting complexes is characterized by scanning probe microscopy and X-ray photoelectron spectroscopy, being complemented by density functional theory calculations and scanning probe microscopy simulations. Our results pave avenues to the engineering of organometallic compounds and steer the development of polyyne chemistry on surfaces., The diacetylene skeletons of DNBD precursors are attacked on Cu(111) by copper adatoms resulting in the synthesis of organocopper metallacycles.

Amino acid properties were optimized for protein secondary structure prediction. The artificial properties were evolved using differential evolution in a property space of arbitrary dimensionality. These properties were optimized to provide the correct results in predicting the elements of the protein secondary structure using a simple classifier model and with standard benchmark sets. A comparison is performed with respect to the use of the commonly employed orthogonal and neutral encoding of the amino acids of the protein chain, together with a discussion of the similarities of the evolved artificial properties with respect to physical properties of amino acids.

Silicon nanoparticles suspended in deionized water were obtained by the laser ablation of solids in liquids technique. A silicon wafer target was ablated with a Nd:YVO4 pico-second laser emitting at 1064 nm with 10 ps pulse width at a repetition rate of 402 kHz with an energy per pulse of 106 µJ. The effect of fluence changes in nanoparticle size and optical properties was studied. The fluence was varied from 2 to 6 J/cm2 by attenuating the beam by means of optical attenuators. Results show a strong relation between nanoparticles size and fluence values. Optical characterization gives bad gap values higher than that of bulk Si, indicating the existence of quantum confinement effects produced by size reduction of Si nanocrystals.

Objectives RF and ACPA are used as diagnostic tools and their presence has been associated with clinical response to some biologic DMARDs (bDMARDs) in RA. This study compared the impact of seropositivity on drug discontinuation and effectiveness of bDMARDs in patients with RA, using head-to-head comparisons in a real-world setting. Methods We conducted a pooled analysis of 16 observational RA registries. Inclusion criteria were a diagnosis of RA, initiation of treatment with rituximab (RTX), abatacept (ABA), tocilizumab (TCZ) or TNF inhibitors (TNFis) and available information on RF and/or ACPA status. Drug discontinuation was analysed using Cox regression, including drug, seropositivity, their interaction, adjusting for concomitant and past treatments and patient and disease characteristics and accounting for country and calendar year of bDMARD initiation. Effectiveness was analysed using the Clinical Disease Activity Index evolution over time. Results Among the 27 583 eligible patients, the association of seropositivity with drug discontinuation differed across bDMARDs (P for interaction Conclusion Seropositivity was associated with increased effectiveness of non-TNFi bDMARDs, especially RTX and ABA, but not TNFis.

Among the plethora of polycyclic structures that have emerged in recent years, indenofluorenes comprise a unique class of compounds due to their potential in organic electronic systems such as OLEDs, OFETs, and OPVCs. However, the synthesis of fully conjugated indenofluorenes without bulky groups on the apical carbons under standard chemistry conditions is not easily accessible. In this regard, on-surface synthesis has appeared as a newly developing field of research, which exploits the use of well-defined solid surfaces as confinement templates to initiate and develop chemical reactions. Here, we demonstrate the successful fabrication of indeno[1,2-b]fluorene π-conjugated polymers linked via cumulene-like connections on well-defined metallic surfaces under ultra-high vacuum conditions. The structure and electronic properties of the formed polymers have been precisely characterized by scanning tunneling microscopy, noncontact atomic force microscopy and scanning tunneling spectroscopy, complemented by computational investigations.

Biofilms on food-contact surfaces can lead to recurrent contamination. This work aimed to study the biofilm formation process on stainless steel plates used in the dairy industry: 304 surface finish 2B and electropolished, and the effect of a cleaning and disinfection process using alkaline (AEW) and neutral (NEW) electrolyzed water. Milk fouling during heat processing can lead to type A or B deposits, which were analyzed for composition, surface energy, thickness, and roughness, while the role of raw milk microbiota on biofilm development was investigated. Bacteria, yeasts, and lactic acid bacteria were detected using EUB-338, PF2, and Str-493 probes, respectively, whereas Lis-637 probe detected Listeria sp. The genetic complexity and diversity of biofilms varied according to biofilm maturation day, as evaluated by 16S rRNA gene sequence, denaturing gradient gel electrophoresis, and fluorescence in situ hybridization microscopy. From analysis of the experimental designs, a cleaning stage of 50 mg/L NaOH of AEW at 30 &deg, C for 10 min, followed by disinfection using 50 mg/L total available chlorine of NEW at 20 &deg, C for 5 min is a sustainable alternative process to prevent biofilm formation. Fluorescence microscopy was used to visualize the effectiveness of this process.

WILHELM OSTWALD BEYOND ANTIATOMISM. The Baltic German chemist Wilhelm Ostwald (1853-1932) had his scientific prestige eclipsed in the history of chemistry due to his rejection to atomic theory, which suggests the permanence of the whig interpretation on history of chemistry in the narratives about him. In this paper, we intend to present elements on Ostwald’s biography far from his role in the atomic controversy from the 19th century, as for example his efforts for the popularization of physical chemistry; his role as a teacher and a textbook writer, and his role as a chemical researcher, being responsible for relevant studies on chemical affinity and catalysis, for example. Finally, we conclude this paper defending that Ostwald’s trajectory cannot be neglected for those interested in history of science.

Weak forces can play an essential role in chemical reactions. Controlling such subtle forces in reorganization processes by applying thermal or chemical stimuli represents a novel synthetic strategy and one of the main targets in supramolecular chemistry. Actually, to separate the different supramolecular contributions to the stability of the 3D assemblies is still a major challenge. Therefore, a clear differentiation of these contributions would help in understanding the intrinsic nature as well as the chemical reactivity of supramolecular ensembles. In the present work, a controlled reorganization of an hexakis[60]fullerene-based molecular compound purely governed by the weakest van der Waals interactions known, i.e. the dihydrogen interaction – usually called sticky fingers – is illustrated. This pre-reorganization of the hexakis[60]fullerene under mild conditions allows a further selective hydrogenation of the crystalline material via hydrazine vapors exposure. This unique two-step transformation process is monitored by single-crystal to single-crystal diffraction (SCSC) which allows the direct observation of the molecular movements in the lattice and the subsequent solid–gas hydrogenation reaction., Weak forces play an essential role in chemistry. Controlling these supramolecular interactions will contribute to the creation dynamic absorbent materials with a variety of technological applications as chemosensors and environmental remediation.

Biodiesel made from oils is rich in polyunsaturated fatty acids methyl esters, and, consequently, presents high tendency to oxidize. Biodiesel made from fats, on the other hand, is mainly comprised by saturated chains. Although it is highly stable, they easily crystalize at low temperatures. Blends from both can exhibit optimized properties. In this work, oxidative stability, expressed by induction period (IP), and cold filter plugging point (CFPP) of blends from palm, palm kernel, babassu, tallow or lard biodiesels with soy one were measured. Biodiesel samples were prepared by two steps transesterification methodology with KOH catalysis followed by H2SO4. IP increases, as the fat biodiesel content in the blend is higher, as expected. Blends comprised by 60% of fat biodiesel by volume had their IP increased from 1.5 (lard) to 2 times (palm kernel), compared to soy one. At this level, IP was found 8 h or higher, except for palm, which 80% was required. CFPP was observed at 8 °C or lower for the blends containing up to 60% of all the fat biodiesel, except for the palm one, which a 20% content must not be surpassed. Palm kernel 80% biodiesel blend reached the Brazilian specification, that is, IP higher than 12 h and CFPP lower than 5 °C.

Research Areas: Food Science & Technology ABSTRACT - With this trial we have tested the effects of structural and chemical composition of neutral detergent fibre (NDF) of the diet on lamb fatty acid composition of meat and subcutaneous fat. Twenty lambs, were fed complete diets with low starch and similar NDF content of different origin (ground alfalfa or soybean hulls). Animal performance and product quality were not affected by treatments. Rumen pH increased and parakeratosis intensity decreased with the level of alfalfa in the diet. Increasing the alfalfa proportion in the diet decreased t10–18:1 (P = .023), increased t11–18:1 (P = .003) and decreased the t10/t11 ratio according to a quadratic pattern (P = .020). Chemical composition and structure of the diet's fibrous fraction influenced the BI pattern of the final product. Forty percent of alfalfa in diet reduced the severity of t10-shift, but for its full resolution, other factors should be considered including forage particle size and buffering capacity of the diet. info:eu-repo/semantics/publishedVersion

Small-molecule-based organic solar cells (OSCs) are a recurrent alternative to polymer-based OSCs. Due to the higher purity and definition of small molecules compared to polymers, the morphological requirements can be more relaxed. Here, we present a series of novel rhodanine-based small-molecule electron donors and blend them with the standard acceptor PC70BM. By performing a target analysis on femtosecond spectroscopy data, we quantify the rates of geminate charge recombination. We are able to reproduce these rates by applying the Marcus–Levich–Jortner equation, using results from quantum chemical calculations. This shows that in a series of differently substituted compounds, one can correctly predict trends in geminate recombination rates by relying only on quantities that are easy to measure (cyclic voltammetry, optical spectra) or that can be calculated by relatively inexpensive methods such as (TD)DFT. Our method should thus accelerate the search for high-performance small-molecule photovoltaic blends.

For the first time, CZTS ink was formulated using low-temperature heating up synthesis of NCs. Besides, the influence of powder concentration on the properties of the films was examined. Subsequently, the CZTS films were annealed under a selenium (Se)/argon (Ar) atmosphere at different temperatures to enhance their properties. The influence of selenization temperature on the properties of CZTS films was examined in detail. Structural analysis showed a peak shift towards lower 2θ values for CZTSSe films because of Se incorporation, resulting in larger lattice parameters for CZTSSe than CZTS. As the selenization temperature increases, an increment in the grain size was observed and the band gap was decreased from 1.52 to 1.05 eV. Hall Effect studies revealed a significant improvement in the mobility and carrier concentration with respect to selenization temperatures. Moreover, film selenized at 550 °C exhibited higher photoconductivity as compared to other films, indicating their potential application in the field of low-cost thin-film solar cells.

We report on the synthesis and characterization of atomically precise one‐dimensional diradical peripentacene polymers on a Au(111) surface. By means of high‐resolution scanning probe microscopy complemented by theoretical simulations, we provide evidence of their magnetic properties, which arise from the presence of two unpaired spins at their termini. Additionally, we probe a transition of their magnetic properties related to the length of the polymer. Peripentacene dimers exhibit an antiferromagnetic (S=0) singlet ground state. They are characterized by singlet–triplet spin‐flip inelastic excitations with an effective exchange coupling (J eff) of 2.5 meV, whereas trimers and longer peripentacene polymers reveal a paramagnetic nature and feature Kondo fingerprints at each terminus due to the unpaired spin. Our work provides access to the precise fabrication of polymers featuring diradical character which are potentially useful in carbon‐based optoelectronics and spintronics., The synthesis and characterization of atomically precise one‐dimensional diradical peripentacene polymers on a Au(111) surface is reported. By means of high‐resolution scanning probe microscopy complemented by theoretical simulations, evidence of their magnetic properties is provided, which arise from the presence of two unpaired spins at their termini.

The development of synthetic strategies to engineer π-conjugated polymers is of paramount importance in modern chemistry and materials science. Here we introduce a synthetic protocol based on the search for specific vibrational modes through an appropriate tailoring of the π-conjugation of the precursors, in order to increase the attempt frequency of a chemical reaction. First, we design a 1D π-conjugated polymer on Au(111), which is based on bisanthene monomers linked by cumulene bridges that tune specific vibrational modes. In a second step, upon further annealing, such vibrational modes steer the twofold cyclization reaction between adjacent bisanthene moieties, which gives rise to a long pentalene-bridged conjugated ladder polymer featuring a low bandgap. In addition, high resolution atomic force microscopy allows us to identify by atomistic insights the resonance form of the polymer, thus confirming the validity of the Glidewell and Lloyd´s rules for aromaticity. This on-surface synthetic strategy may stimulate exploiting previously precluded reactions towards π-conjugated polymers with specific structures and properties., Development of strategies for the synthesis of pi-conjugated polymers is hampered by limited solubility. Here, the authors report a synthetic protocol based on the search for specific vibrational modes through an appropriate tailoring of the p-conjugation of the precursors, in order to increase the attempt frequency of a chemical reaction.

Background Lupus Nephritis (LN) is one of the most severe manifestations of Systemic Lupus Erythematosus (SLE). We aimed to compare proliferative (PLN), membranous (MLN) and mixed LN regarding clinical and laboratory presentation, and serologic profiles. Previous work suggested that these groups differ in autoantibody profile and complement levels, but those reports mainly originate from single-centres. Methods Multicentre observational study, with retrospective analysis of a prospective cohort, using data from the Portuguese registry of rheumatic diseases–Reuma.pt. Patients with biopsy-proven PLN, MLN and mixed LN were included. The first renal biopsy showing one of these classes was considered, for each patient. Groups were compared using Pearson’s Chi-Square for categorical variables and One-Way ANOVA or Kruskal-Wallis for numerical variables. Results 232 patients were included (87% females; 88.5% White Europeans). Median follow-up was 7 years (IQR 10.75; maximum 35 years). As seen in table1, the level of proteinuria did not differ between groups; however, MLN patients presented with significantly lower creatinine. Levels of complement were reduced in PLN and mixed LN but were normal in MLN patients, and this difference was statistically significant. Groups also differed regarding the proportion of positivity for anti-dsDNA (higher in PLN) and anti-RNP antibodies (higher in MLN). There was a lower SLEDAI in MLN, probably linked with the lower prevalence of anti-dsDNA antibodies and complement consumption in this group. Conclusions Our results support previous findings from single-centre studies suggesting that MLN has a different serological profile than PLN, possibly reflecting different pathogenesis.

Growth performance, carcass and meat quality of 16 Alentejana bulls fed for 90 days with a conventional cereal-based (Control) or a high-fibre and low-starch (HFLS) diet were studied. The HFLS diet included 20% alfalfa hay, 4.8% soybean oil, 6% soybean hulls, 6% dehydrated citrus and 6% sugar beet pulps in substitution of grain. Ryegrass hay was offered to a maximum of 20% of total intake in both diets. Bulls were individually housed, weighed every 14 days, and feed intake was registered daily. Average daily weight gain, dry matter intake, carcass and most meat quality traits were not affected by the diet (P > .05). Feeding an HFLS diet, therefore, can improve beef fatty acid profiles without negatively impacting animal performance or meat quality.

Electronic studies in molecular systems have been used to evaluate the possibility of improvements in the efficiency of physicochemical processes of interest in electronic devices. We have studied complex molecular systems prototypes in our research area, especially involved in intra- and intermolecular electron transfer. In this work, we performed the spectral recording of uranyl acetate dihydrate in aqueous solution to characterize its spectral properties, related to the deformation of the electronic configuration, against the incidence of uv-visible radiation, in order to functionalize the spectral properties of uranium, by the insertion of donor species of electron pairs. For this we evaluate the electronic polarizabilities, by the use of the program POLAZ-F2.

CuAlO2 and CuAl2O4 thin films were synthesized by the deposition of the precursor metals using the physical vapor deposition technique and subsequent annealing. Annealing was carried out for 4–6 h in open and nitrogen atmospheres respectively at temperatures of 900–1000 °C with control of heating and cooling ramps. The band gap measurements ranged from 3.3 to 4.5 eV. Electrical properties were measured using the van der Pauw technique. The preferred orientations of CuAlO2 and CuAl2O4 were found to be along the (1 1 2) and (3 1 1) planes, respectively. The phase percentages were quantified using a Rietveld refinement simulation and the energy dispersive X-ray spectroscopy indicated that the composition is very close to the stoichiometry of CuAlO2 samples and with excess of aluminum and deficiency of copper for CuAl2O4 respectively. High resolution transmission electron microscopy identified the principal planes in CuAlO2 and in CuAl2O4. Higher purities were achieved in nitrogen atmosphere with the control of the cooling ramps. Keywords: PVD, Copper aluminates, Thin films

Purpose: To assess whether optical coherence tomography (OCT) could be useful for detecting and documenting fixation in patients with microtropia. Methods: Retinal fixation observation was performed using spectral-domain OCT on amblyopic children with microtropia. The position between the retinal fixation point and the anatomical fovea was measured, in microns, using the system software tools. Only patients with a high level of cooperation, OCT scan quality signal of 7 or better, and visual acuity of 0.70 logarithm of the minimum angle of resolution (logMAR) or worse in the amblyopic eye were included. Results: A total of 25 patients were included: 15 with microtropia (study group) and 10 without tropia and with foveal fixation and stereopsis (control group). In the study group, microtropia was previously diagnosed in 67% of cases through the cover test, and was predominantly in the left eye (73%). The average visual acuity of the sound eye was 0.03 decimal and 0.18 logMAR in the amblyopic eye. The microtropia was 3.73 ± 3.34 prism diopters and eccentric fixation (387 ± 199 µm) with OCT was observed in all cases except one. Eccentricity was predominantly in the superonasal quadrant (57%). Both eyes in the control group and the contralateral eyes of the study group showed foveal fixation. Conclusions: OCT can play an important role in the diagnosis and measurement of eccentric fixation in eyes with microtropia, providing high sensitivity. [ J Pediatr Ophthalmol Strabismus . 2018;55(3):171–177.]

Rice is one of the most produced and consumed cereals in the world, making the control of its chemical composition, especially of minerals, important. A method of rice digestion using nitric acid and hydrogen peroxide to determine metals (Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn) using Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) was developed. The optimized conditions were established using a factorial design 23, obtaining the following digestion conditions as the most adequate: digestion time (20 min), concentration of HNO3 (8 mol L− 1) and H2O2 volume (2.5 mL). Recovery values ranging from 80 to 120% with RSD

The role of the Tenango del Aire mountain pass, located southeast of the Mexico City Metropolitan Area (MCMA), in venting the city's air pollution has already been studied from a meteorological standpoint. To better understand the transport of gaseous air pollutants through the Tenango del Aire Pass (TAP), and its influence on the air quality of the MCMA, three mobile air quality monitoring units were deployed during a 31-day field campaign between February and March of 2011. Surface O3, NOx, and meteorological variables were continuously measured at the three sites. Vertical profiles of O3 and meteorological variables were also obtained at one of the sites using a tethered balloon. Days were classified as being under low pressure synoptic systems (LPS, 13 days), high pressure synoptic systems (HPS, 13 days), or as transition days (TR). The Mexican ozone standards at the Pass were not exceeded during LPS days, but were exceeded on almost all HPS days. A detailed analysis was performed using data from two typical days, one representative of LPS and the other of HPS. In both cases, morning vertical profiles of O3 showed a strong thermal inversion layer and near-surface O3 titration due to fresh NOx. In the LPS early morning, a single O3 layer of close to 45 ppb was observed from 150 to 700 magl. In the HPS early morning, 50 ppb was observed from 150 to 400 magl followed by a 400-m-thick layer with up to 80 ppb. These layers were the source of the morning increase of O3, with a simultaneous sharp decrease of NOx and CO as the mixing layer started to rise. During the LPS day, a southerly wind dominated throughout most of the daytime, with surface O3 lower than 60 ppb. The same was observed for the well-mixed midday and afternoon vertical profiles. Under HPS, northerly winds transported photochemically active air masses from the MCMA all morning, as observed by a smoother increase of Ox and O3, reaching 110 ppb of O3. Just after midday, the wind shifted back, carrying high-O3 (100–110 ppb) aged air masses until sunset. In addition, the midday and afternoon vertical profiles showed well-mixed high-O3 (100–110 ppb) mixing ratios. Analysis of Ox-NOx correlations was performed for these peri-urban and MCMA sites. A parallel analysis for the nearest urban air quality monitoring station in the MCMA was also done. A comparison allowed us to distinguish between photochemically active (VOC sensitive) or aged parcels (NOx sensitive) arriving at the TAP. Separating the correlations into time groups associated with wind direction changes allowed us to better distinguish between local, MCMA, or regional influence. The results are relevant to air quality management in the Mexico City megalopolis.

The purpose of this study was to characterize mineral trioxide aggregates (MTA) enriched with iron disulfide (FeS2 ) nanostructures at different concentrations, and to investigate their storage modulus, radiopacity, setting time, pH, cytotoxicity, and antimicrobial activity. Iron disulfide nanostructures [with particle size of 0.357 ± 0.156 μm (mean ± SD)] at weight ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 wt% were added to white MTA (wMTA). The radiopacity, rheological properties, setting time, and pH, as well as the cytotoxicity (assessed using the MTT assay) and antibacterial activity (assessed using the broth microdilution test) were determined for MTA/FeS2 nanostructures. The nanostructures did not modify the radiopacity values of wMTA (~6 mm of aluminium); however, they reduced the setting time from 18.2 ± 3.20 min to 13.7 ± 1.8 min, and the storage modulus was indicative of a good stiffness. Whereas the wMTA/FeS2 nanostructures did not induce cytotoxicity when in contact with human pulp cells (HPCs) and human gingival fibroblasts (HGFs), they showed bacteriostatic activity against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. Adding FeS2 nanostructures to MTA might be an option for improving the root canal sealing and antibacterial effects of wMTA in endodontic treatments.

The expensive ITO has widely been used as an electrode for fabricating organic photovoltaic solar cells (OPV), which turns out to be an obstacle to the commercialization of solar cells. Therefore, in this work, we aim to replace the ITO with fluorine-doped tin oxide (FTO), which is 40 times cheaper than ITO. Besides, titanium dioxide is used as an electron transport layer instead of zinc oxide (ZnO). The active layer comprises the conductive polymer PTB7 as a donor and the fullerene derivative of PC70BM as an acceptor. The inverted OPV is fabricated with FTO/TiO2/PTB7:PC70BM/MoO3/Ag device structure. The fabricated OPV showed a power conversion efficiency (PCE) of 0.48%. Therefore, to enhance the PCE of the OPV, the device parameters such as the thickness of each layer, thermal treatment of the active layer and the OPV are optimized. As a result, the PCE is greatly enhanced from 0.48% to 2.88%. Furthermore, the open-circuit voltage, short circuit current density, and fill factor are significantly improved. The degradation efficiency measurements are reported. Hence, this research demonstrates a new pathway towards enhancing the OPV with stable, non-toxic and low-cost materials.

Antimony sulfide thin films were deposited on glass substrates at room temperature by pulsed laser deposition using pellets of Sb2S3 as the target. The structural characterization showed that the as-grown films have a high amorphous contribution, and the annealed samples have the Sb2S3 orthorhombic phase. The values for the calculated crystal sizes of 27, 25, and 26 nm for the annealing temperatures of 250, 275, and 300 °C, respectively, for the case of transmission for the as-grown sample amount to 30%, while for the annealed samples, the value is less than 10%. In the reflection measurements, the as-grown sample and the one annealed at 250 °C present lower values at 10%, while for the samples annealed at 275 and 300 °C, the reflection values are between 25% and 35%. On the other hand, the bandgap through the Tauc’s parabolic band method was calculated, with its value for the as-grown sample being 1.92 eV, while for the samples annealed at 250, 275, and 300 °C, the bandgap values are 1.31, 1.66, and 1.29 eV, respectively. The atomic percentage determined by Energy Dispersive Spectroscopy was 36% Sb and 64% S for the as-grown sample, while for the annealed samples, the percentage of sulfur increases, and the percentage of antimony decreases until a final value of 30.5% Sb and 69.5% S for the sample annealed at 300 °C.

The purpose of this study was to analyze and quantify spectral parameters, the absorption bands, specifically in the uv-visible region of some N-oxide ligands. From the spectra, the area under the absorption band, the molar absorptivity, the integrated absorption coefficient and the oscillator strength by the Gaussian approximation method were calculated for each of them, using the proposed evaluation by Drago and Figgs. According to the obtained results, it can be concluded that the heterocyclic compounds studied absorb very well electromagnetic radiation in the ultraviolet region. For the ligands QUI-NO and NIC-NO it was observed that there are two types of bands, primary and secondary, being transitions of type π → π * and n → π*, respectively. For DITBIS-NO, there was only one primary band (transition 1) and two additional shoulders, which had the highest observed absorbance coefficient. These ligands are expected as potential electron donors in complex systems whose purpose is to change the energy levels of the electronic system in order to promote a better utilization of the absorbed energy and therefore a better efficiency.